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CROSS RELATED APPLICATION
[0001] This application is a divisional of application Ser. No. 12/257,666 filed Oct. 24, 2008 and claims the benefit of U.S. Provisional Application No. 61/013,891 filed Dec. 14, 2007, the entirety of which both applications are incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to separating fibers from lignocellulosic materials, such as the separating fibers from wood chip feed material. The invention particularly relates to mechanical refining, including chemi-mechanical pulping (CMP) and thermomechanical pulping (TMP).
[0003] In some conventional mechanical refining processes, the steps of defibration and fibrillation are performed together in a single mechanism. The benefits of separating the steps of wood fiber defibration and fiber fibrillation are discussed in, for example, U.S. Pat. No. 7,300,541 ('541 patent), which is based on published international patent application PCT/US03/22057. When fibers are defibrated prior to fibrillation, the primary refining step may be optimized for fibrillation. The optimization for fibrillation may be to minimize energy dissipation by increasing refining intensity. A method to separate the defibration and fibrillation steps is described in the '541 patent a using a pressurized chip press followed by gentle refining to separate fibers in a pretreatment stage (referred to as a “defibration step”) and thereafter by high intensity pressurized primary refining stage (the “fibrillation step”).
BRIEF DESCRIPTION OF THE INVENTION
[0004] Specific treatment agents have been developed to be applied to defibrated wood fibers to enhance the efficiency and quality development of mechanical refining process. The treatments may include acidic, neutral or alkaline chemical agents, and enzymatic agents. The type of agent(s) and the point(s) in the refining process of application of the agent to the defibrated wood fibers may be optimized to enhance process efficiency. Process efficiency may be defined by any one or more of physical pulp quality, enhanced brightness, and energy savings. The treatments with agents disclosed herein may also provide: 1) an ability to utilize in a refining process inferior wood species and sawmill residues, and 2) simplification of the refining process downstream of the primary refining stage.
[0005] The treatments with agents disclosed herein may be applied to target specific application points of agents during the thermal and mechanical refining process, such as described in the '541 patent. Depending on the agent used in the treatment, the application point of the agent may be during or immediately following one or more of a defibration step (preferably using enzymatic agents), during a fibrillation step (preferably using chemical agents) and/or immediately following a fibrillation step (preferably using bleaching agents). The selected agent is an important factor in determining the optimum point to apply the agent to the refining process to, for example, improve process efficiency.
[0006] The processes and treatments disclosed herein preferably are preformed such that defibration and fibrillation are separate stages, and preferentially preformed in separate mechanisms. Alternatively, the separation of the defibration and fibrillation steps may be preformed in a single mechanism, such in a mechanical refiner having two or more refining zones arranged in series. Preferably, the defibration step achieves at least a 30 percent (30%) conversion of intact wood fibers to well separated fibers, and preferably greater than 70 percent (70%) conversion with less than 5% fibrillation. From the pre-treatment (defibration) step, the defibration level preferably results in 40 percent to 90 percent (40% to 90%) of separated fibers in the material. The primary refiner step (fibrillation) should preferably achieve at least 90 percent (90%) of fibrillated fibers.
[0007] The processes and treatments disclosed herein may be applied to lignocellulosic materials including wood chips from softwoods and hardwoods, other types of lignocellulosic material, including material that is currently viewed as less desirable for use in the existing mills.
[0008] A mechanical pulping method has been invented that in one embodiment includes: defibrating a comminuted cellulosic material; mechanically refining the defibrated cellulosic material in a primary refining step; introducing to the cellulosic material at least one of a chemical agent and a biological during the defibration step or the mechanical refining step, and producing pulp from the refined and defibrated cellulosic material.
[0009] The mechanical pulping method may include introducing the chemical agent to the cellulosic material when in the primary refining step and the biological agent to the cellulosic material when in the pre-treatment step. Further, the defibration step may include a pressurized chip press stage and subsequently a fiberizer refiner stage. And, the introduction of the biological agent may be in the pre-treatment step and specifically between pressurized chip press stage and the fiberizer refiner stage or directly into the fiberizer refiner stage.
[0010] A mechanical pulping apparatus has been invented that in one embodiment comprises: a pre-treatment defibration device receiving comminuted cellulosic material; a primary refiner receiving the comminuted cellulosic material discharged from the pre-treatment defibration device; a source of at least one of a biological agent and a chemical agent, and a conduit from the source coupled to at least one of the defibration device and the primary refiner, wherein the conduit delivers the at least one of the biological agent and the chemical agent to at least one of the defibration device and the primary refiner.
[0011] In another embodiment, a mechanical pulping apparatus comprising: a pre-treatment defibration device receiving comminuted cellulosic material; a primary refiner receiving the comminuted cellulosic material discharged from the pre-treatment defibration device; a source of a biological agent and a chemical agent, and a inlet to the pre-treatment defibration device for a biological agent; a primary refiner receiving the comminuted cellulosic material discharged from the pre-treatment defibration device, and an inlet to the primary refiner for a chemical agent.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a schematic drawing of a section of a wood chip.
[0013] FIGS. 2 to 7 are flow charts of mechanical refining processes using agents, such as chemical and biological agents, to treat lignocellulosic materials undergoing mechanical, chemi-mechanical and thermo-mechanical refining
DETAILED DESCRIPTION OF THE INVENTION
[0014] Refining, in the context of the present application, generally includes a pre-treatment stage (defibration) and a primary refining stage (fibrillation). The pre-treatment stage (defibration) fiberizes the wood chip feed material under mechanically gentle and low intensity conditions, e.g., pressurization, to initiate the separation of individual fibers from the matrix of fibers in a wood chip. The primary refining stage generally involves high mechanical intensity forces, e.g., shearing and impact pulses, that fibrillate the wood chip material into pulp. During fibrillation, the fibers are peeled and fiber wall material is unraveled. The refiners used to fibrillate may be mechanical conical or disc refiners with refining plates having single or multiple refining zones.
[0015] FIG. 1 is a diagram of a wood chip 10 having softwood fibers 12 bonded together in a wood chip. The bonding material is primarily found in the middle lamellae 14 between the fibers 12 that contains a high concentration of lignin. The structure of each fiber 12 includes various layers identified as P, and the S layers which include three individual layers labeled S1, S2 and S3. The P layer represents the primary wall of each cell of a fiber. The S layers represent the secondary wall of the fiber cell, wherein the S1 layer is an outer layer of the secondary wall, the S2 layer is a main body of the secondary wall of the fiber, and the S3 layer is an inner layer of the secondary wall.
[0016] During fibrillation, the fibril rich layer S2 is delaminated, e.g., peeled off, as much as is practical from each fiber. The S2 layer contains the largest mass of fibrils in the fiber structure. The surface area of bonding material is improved by peeling or by delaminating the S2 layer. An increase in the surface area correlates positively to increases in desirable pulp properties such as tensile strength and scattering coefficient. Fibrillation in the pretreatment stage exposes the fibrous areas of the fiber for subsequent fibrillation in the primary refining stage.
[0017] The addition of an agent at one or more stages in the refining process where the material is fiberized or defibrated is believe to cause reactions that open the wood fiber matrix and expose fibrous wall material for efficient softening and maximum fiber fibrillation, e.g., delamination of fibrous wall material. All fiber layers (P, S1, S2 and S3) of the lignocellulosic material 10 receive treatment by the agent. The reaction between the agent and the S2 layer enhances fibrillation of the S2 layer.
[0018] The agent may be chemicals (acidic, neutral, alkaline), enzymes, fungus, bacteria, or the like and any combination thereof. The agent may be applied at various locations in the refining mechanism(s) and at various stages of the refining process.
[0019] The agent, in one embodiment, is preferably a chemical based agent that is introduced during a primary refining step (fibrillation step) to minimize reaction time between the agent and wood material. Introducing the agent in this manner should lead to preferential softening and reaction of the fiber wall material more so than of the lignin-rich middle lamellae, and, thereby, maximize the exposed specific fiber surface area via delamination of the wall material in the S2 layer, and ultimately fiber bonding. Further, it is preferred that the chemical agents not be applied for long exposure periods to the fiber structure because of the potential for producing long fibers coated in lignin.
[0020] In another embodiment, a biological agent, such as an enzyme, may be applied during the defibration step to allow an increase in reaction time of the agent on the wood structure, as compared to the short reaction time resulting by adding a chemical agent in the primary refining stage. Biological agents in general require a retention time of at least 15 minutes to properly react with the wood structures and achieve a desirable benefit in softening the S2 layer. Proper application of the agent, such as the chemical agent in the primary refiner (fibrillation) and the biological agents in the fiberizer refiner (defibration step) is desired to yield enhanced pulp quality.
[0021] Following treatment with agent(s), a further mechanical refining device or other pulp device(s) may apply shear and compressive forces to the wood chips to further fibrillate and provide other beneficial properties to the pulp, including brightness enhancement, extractives removal, optical enhancement and fiber development (tensile, elasticity, fiber length, high specific surface, etc.).
[0022] The application of an agent, e.g., a chemical or biological agent, to a process stage may provide a reduction of operating costs by improved energy efficiency and optimized chemical usage. Further, by introducing an agent, e.g., chemical agent, to the fillibration process, the agent may provide improved optical properties of the refined pulp, including properties of enhanced light scattering and opacity of the pulp. An enhanced scattering coefficient may be achieved by the agent contributing to a high specific surface of the fibers. The use of agents may also allow for a simplification of the refining process stages and related reductions in investment costs.
[0023] Another benefit of applying agents to a refining process is increased extractives removal, which is consideration particularly relevant in refining resinous wood species. When defibrating and opening the fiber structure of a resinous wood, extractives of the wood may be extruded from the wood and processed by downstream dewatering equipment. Another benefit of the application of agents disclosed herein is to improve the homogenization of woods with varying density and extractives content. Adding agents may also improve the bonding ability of inferior woods by 20 percent or more at a given freeness. Additionally, the use of agents may allow for components of wood, for example sawmill residues, to be used as a wood feed material for refining, where such components were not previously useable.
[0024] FIGS. 2 to 7 are flow charts of the application of one or more chemical agents in a mechanical, chemi-mechanical or thermomechanical refining process (collectively referred to as mechanical refining). The flow chart of FIG. 2 is for a full refining treatment, with chemicals and bleaching, of wood chips. Wood chips 20 are fed to a chip washing stage 22 and conveyed to a two-step pre-treatment, e.g., Defibration stage 24 . The first step 26 of the pretreatment stage 24 is a pressurized chip press 26 operating at less than 2 bar gauge pressure, which is followed by a fiberizer refining step 28 operating at less than 3 bar gauge pressure. The photographic image shows the wood chips after application of the pressurized chip press 26 and the image 32 shows the wood chips after application of the fiberizer refining step 28 . In this pre-treatment stage 24 , chemical agents are preferably not added.
[0025] Following the pre-treatment stage 24 , the wood chips are treated in a primary refining stage (fibrillation) 34 which may include a pressured feeding device, a steaming device, a mechanical disc or conical refiner, wherein the refiner may also include a blowline (e.g., all pressured equipment from the feeder to the blowline) and operate at greater than 3 bar gauge pressure. One or more chemical agents 36 are added to the primary refining stage 34 . Adding chemical agents at the primary refining stage may be helpful in reducing the reaction time between the agent and wood material.
[0026] Another advantage of adding a chemical agent at the primary refiner stage 34 , as opposed to the pretreatment step 24 , is that chemicals agents are not squeezed out, e.g., extruded from the wood chips, during pressurization of the wood chips or by a plug screw 33 feeding the primary pressurized refiner. By allowing the agents to be retained in the chips, the agent reacts with the wood fibers with a full charge of the chemical agent.
[0027] The chemical agent(s) may include bleaching chemicals, preferably MgOH 2 and H 2 O 2 . If the chemical agent is or is combined with oxidative bleaching liquors, such as alkaline peroxides, the agent and bleach may be introduced: i) directly in the primary refiner 34 , ii) in the primary refiner blowline 35 , or iii) in a split between the primary refiner and blowline. Adding alkaline bleach liquor as or with the chemical agent at the blowline should reduce or minimize the decomposition of oxidative bleaching agents such as H 2 O 2 . However, the full benefit of energy reduction and strength development attributable to the agent may not be realized unless some or all of the alkaline is added during primary refining stage. Accordingly, the bleach chemical agents may also be added at the inlet to the primary refiner and to the blowline for the refiner.
[0028] The bleaching chemical agent may also be discharged from an interstage bleach tower 38 between the primary refiner and subsequent processing steps 40 to enhance the brightening response of the resulting pulp. The use of a bleaching chemical agent in the manner shown in FIG. 2 may allow for the elimination or substantial reduction of further bleaching operations in the conventional processing steps 40 .
[0029] FIG. 3 is a flow chart of an exemplary mechanical refining process 42 where the pre-treatment step (partial defibration) 24 is a single step of a pressurized chip press 26 operating at less than two bar gauge pressure followed by a primary refining stage 34 . A screw, e.g., a plug screw, moves the chips from the pretreatment step 24 to the primary refining state 34 . The flow chart shown in FIG. 3 represents a medium treatment with chemicals of the wood chips. The primary refining stage 34 may include a pressurized feeding device, a steaming device, a mechanical refiner including a blowline 35 , wherein preferably the pressured equipment from the feeder to the blowline operates at greater than 3 bar gauge, and preferably between 5 ad 6 bar. The primary refining stage may be segmented into an inner zone for defibration and outer zone for fibrillation. A chemical agent 36 is added to the primary refining stage 34 . If bleaching chemicals are added with chemical agent, an interstage bleach tower (see 38 in FIG. 2 ) may be included to maximize brightness of the pulp discharged from the primary refining stage. Further, the bleaching chemicals may also be added to the primary refiner inlet and the refiner blowline.
[0030] FIG. 4 is a flow chart of a process 44 that does not have a pre-treatment step, such as shown in FIGS. 2 and 3 . The process 44 is a light treatment with chemicals. In this process 44 , chips 20 from chip washing stage 22 flow directly to the primary refining stage 34 which includes a blowline. In this process 44 , the primary refining stage 22 includes at least two distinct refining zones, wherein the first refining zone is arranged to defibrate the wood chips and a subsequent refining zone is arranged to fibrillate the fibers. The primary refining stage 34 may include a pressured feeding device, steaming device, a mechanical refiner including a blowline, wherein preferably the pressured equipment from the feeder to the blowline operates at greater than 3 bar gauge. Bleach chemicals agents may also be added to the inlet to the primary refiner and to the refiner blowline.
[0031] The chemical agent 36 preferentially occurs after the defibration refiner plates and before the outer fibrillation refiner plates. In conical refiners the chemical is preferentially added after the flat defibrating plate zone and before the conical fibrillating plate zone. In flat disc refiners the chemical agent is preferentially added after the flat inner defibrating zone and before the flat outer fibrillating zone of refiner plates. Most large flat disc refiners have a circumferential gap between the inner and outer refiner plates where dilution water or a chemical agent may be added.
[0032] Bleaching chemicals can be added with or as the chemical agent 36 , in a similar fashion as described above for introducing a bleaching agent with or as the chemical agent. If bleaching chemicals are added as part of the chemical agent, an interstage bleach tower 39 may be included between the primary refining stage 34 and conventional processing steps 4 .
[0033] FIG. 5 is a flow chart of a process 46 that uses biological agents. Wood chips 20 are pressed and fed to a chip washing stage 22 and conveyed to a two-step pre-treatment stage 24 . The pretreatment stage includes a pressurized stage 26 , that preferably includes a chip press operating at less than 2 bar gauge pressure, and a fiberizer refining step 28 , preferably operating at less than 3 bar gauge pressure. The process 46 introduces biological agent(s) 48 to the pre-treatment stage 24 . The biological agent(s) may be added to one or both of: (1) the discharge line 50 between the pressurized chip press in the pressurized stage and the inlet of the fiberizer refiner in step 28 and (2) directly into the fiberizer refiner. Flow lines 52 and valves 54 direct the biological agent(s) to one or both of the discharge line 50 and the fiberizer refiner 28 . The biological agent(s) 48 may also be added to the process 46 between a chip press 20 and the fiberizer refiner 28 and to the fiberizer refiner.
[0034] Following the pre-treatment stage 24 , a bin 56 in which the wood material is retained for, for example, 15 minutes to 3 hours, to allow for continued reactions between the material and the biological agent. After the bin, the wood material is conveyed to the primary refining stage 34 , which may include a pressured feeding device, steaming device, a mechanical refiner including a blowline, wherein preferably the pressured equipment from the feeder to the blowline operates at greater than 3 bar gauge.
[0035] FIG. 6 is a flow chart of a process 58 in which biological agents 48 and chemical agents 36 are applied to the wood material (chips) being refined by the process. The wood chips 20 are pressed and fed to chip washing stage 22 , and conveyed to the two-step pre-treatment stage 24 . The pressurized chip step 26 may include a pressurized chip press operating at less than 2 bar gauge pressure followed by a second fiberizer refining step 28 operating at less than 3 bar gauge pressure. The biological agent(s) 48 are added to the pre-treatment stage 24 . Preferably, the chemical agent(s) are not added to the pre-treatment stage. The biological agents may also be added to the process 58 between the chip press 20 and fiberizer refiner 28 or in the fiberizer refiner. The chemical agents may also be added to the inlet of the primary refiner blowline.
[0036] After the pre-treatment stage 24 the wood material is processed by the primary refining stage 34 which may include a pressurized feeding device, steaming device, a mechanical refiner having a blowline, wherein the process from the pressurized feeding device to the blowline operates at preferably greater than 3 bar gauge. The chemical agent 36 is added to the primary refining stage. The chemical agents may include bleaching chemicals, preferably Mg(OH) 2 and H 2 O 2 . If a bleaching agent(s) is included as or with the chemical agent, some or all the chemical agent and bleach may be added at the primary blowline. If a bleaching liquor is the only chemical agent used, at least some or all of the chemical agent should be applied at the primary refiner to enhance energy savings and pulp strength development. If a bleaching agent is added, an interstage bleach tower (see FIG. 4 ) should preferably be between the primary refiner stage 34 and subsequent processing steps 40 . The use of bleach agents as or with the chemical agent added to the primary refining stage 34 may allow for the elimination or substantial reduction of bleaching stages in the conventional processing steps 40 .
[0037] FIG. 7 is a flow chart, e.g., flowsheet, of an exemplary mechanical pulping process 60 in which at least one chemical agent 36 . The chemical agent is, by way of example, an alkaline peroxide agents applied at the primary refining stage 34 and the process 60 includes an interstage bleaching stage 38 . The process 60 is a simplified refining process, wherein the simplifications include elimination of: i) pressurized screening of the mainline pulp, ii) dewatering and refining of mainline screen rejects, iii) a disc filter dewatering to pulp storage, and iv) a post bleach plant. By eliminating one or more of these mechanism typically found in mechanical pulping processes, there is a substantial cost savings in the installed equipment cost as compared to a conventional thermomechanical pulping system. Further, the process 60 may provided reduced productions costs due to the elimination of one or more of the processes i to iv identified above.
[0038] The use of agents, such as chemical and biological agents, to the pretreatment stage 24 and primary refining stage 34 described herein may simplify the scope and complexity of the refining processing steps downstream of the primary refiner stage 34 and, thereby, reduce costs of the downstream equipment. The use of agents as described herein may improve fiber bonding and reduce skive content of the resultant pulp after mainline refining such that no or minimal screening is needed for the mechanical pulping process.
[0039] Conventional processing steps may be performed following the interstage bleaching. The steps may include a pulp press and washing stage 62 , secondary and tertiary mechanical refining steps 64 and 66 preformed at or below a 4 bar gauge pressure, and a medium consistency pulp storage stage 68 which may include storing the pulp in a storage tower.
[0040] Several trials have been completed to demonstrate the usefulness of the invention. These trials are presented in the examples below:
[0041] Trial 1:
[0042] The location of the addition of an agent to the pulp process should be selected to maximize pulp strength development at a given application of specific energy. The example of trial 1 compares pulps produced using the process with an agent (acid sulfite) applied at two different addition locations; where one is at the defibration stage, and a second is at the fibrillation stage (primary refiner). Table A presents results for both refiner series interpolated at a total specific energy application of 2400 kWh/ODMT.
[0000]
TABLE A
Comparison of Acid Sulfite applied at Defibration (Fiberizer)
versus Fibrillation (Primary Refiner) steps
Chemical Addition Point
Defibration
Fibrillation
Na2SO 3 (%)
3.9
3.7
Tensile Index at 2400 kWh/ODMT
39.6
42.7
Shive Content (%) at 2400 kWh/ODMT
0.04
0.01
[0043] The addition of chemical at the fibrillation step reduced the time exposure for the sulfite to react and soften the wood lignin. Preferential fiber softening takes place within the fiber wall material which in turn improves fiber development.
[0044] Trial 2:
[0045] The trial 2 example shows the importance of increasing wood fiber defibration following chip destructuring. P. taeda wood chips were partially defibrated in a pressurized chip press in both examples followed by application of a chemical agent, sodium sulfite, in the refining steps. Table B presents both refiner series interpolated at a freeness of 150 mL.
[0000]
TABLE B
Effect of Increasing Wood Fiber Defibration
prior to Chemical Treatment
Without Fiberizer
With Fiberizer
Defibration
Defibration
Na 2 SO 3 (%)
3.3
2.8
Freeness (mL)
150
150
SEC (kWh/ODMT)
2092
1965
Bulk (cm 3 /g)
3.36
3.28
Tensile Index (Nm/g)
23.9
31.2
Tear Index (mN · m 2 /g)
6.8
9.2
Shive Content (%)
0.02
0.02
ISO Brightness (%)
55.2
54.9
[0046] The increased fiber defibration improves the efficiency of chemical penetration into exposed fiber wall material during the primary refining step, with resultant improved pulp quality.
[0047] Trial 3:
[0048] The example of trial 3 demonstrates that inferior wood species and sawmill residues can be utilized for the production of usable pulps in mechanical printing papers with less negative impact. Trial 3 illustrates the effect of adding 29% P. taeda sawmill residues on pulp properties produced using the new process. Table C compares the pulps interpolated at a freeness of 70 mL.
[0000]
TABLE C
Effect of adding sawmill residues (slabwood chips)
Reference
29% Sawmill
100% Sawmill
Pulp*
Chips**
Chips
NaHSO 3 (%)
3.4
3.2
3.1
Freeness (mL)
70
70
70
SEC (kWh/ODMT)
2036
2354
2495
Bulk (cm3/g)
2.55
2.69
2.78
Tensile Index (Nm/g)
39.6
42.3
39.0
Tear Index (mN · m2/g)
8.1
8.9
9.0
Shive Content
0.04
0.04
0.04
ISO Brightness (%)
52.5
50.3
48.1
Wherein “*” indicates that the chip feed material is produced from 100 percent (100%) whole log P. taeda chips and “**” indicates that the chip feed material is produced with 29 percent (29%) sawmill (slabwood) P. taeda chips added to whole log P. taeda chips.
[0049] The resultant pulp produced with 29% sawmill chips (slabwood) had only slightly higher bulk and lower brightness. Increasing the application of acid sulfite (NaHSO 3 ) treatment may be used to equalize pulp properties such as bulk and brightness to that of the reference pulp.
[0050] Trial 4:
[0051] Trial 4 presents alternative chemical agents applied to the fibrillation step (primary refiner) of the novel process. The wood furnish used for the study was P. taeda from Tennessee, USA. Table D presents pulp series produced using two different chemical treatments, wherein the agents are: 1) a bleaching agent solution of magnesium hydroxide (Mg(OH) 2 ), hydrogen peroxide (H 2 O 2 ), and 2) acetic acid. A conventional TMP pulp produced from the same P. taeda wood chips is also included for comparison. The results are interpolated at a freeness of 150 mL from the secondary refined pulps.
[0000]
TABLE D
Alternative Chemical Treatments
Conventional
TMP
Invention
Invention
Chemical Treatment
0
4.0% Acetic
1.5% Mg(OH) 2
Acid
2.4% H 2 O 2
Freeness (ml)
150
150
150
SEC (kWh/ODMT)
2698
2098
1831
Tensile Index (Nm/g)
28.9
33.4
35.9
Burst Index (kPa · m 2 /g)
1.51
1.69
1.91
Tear Index (mN · m 2 /g)
11.5
11.4
11.6
Scattering Coefficient
44.4
49.0
45.1
(m 2 /kg)
ISO Brightness (%)
47.7
36.7
59.7
[0052] Both chemical agents demonstrated an ability to significantly reduce energy consumption and increase pulp strength properties compared to the thermomechanical (TMP) pulp. The series produced with bleaching agents [1.5% Mg(OH) 2 and 2.4% H 2 O 2 ] resulted in a significant gain in brightness.
[0053] The brightness of mechanical pulps from inferior wood species with dark color bearing chromophore structures can be effectively brightened when using the novel process in tandem with bleaching agents and/or interstage retention. Such applications increase the possibility of using inferior woods and the scope of downstream bleaching equipment.
[0054] While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not to be limited to the disclosed embodiment, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the invention. | A mechanical pulping apparatus including: a pre-treatment defibration device receiving comminuted cellulosic material; a primary refiner receiving the comminuted cellulosic material discharged from the pre-treatment defibration device; a source of a biological agent; a first conduit from the source of the biological agent coupled to pre-treatment defibration device, wherein the first conduit delivers the biological agent to or immediately upstream of an inlet to the defibration device; a source of a chemical agent, and a second conduit from the source of the chemical agent coupled to primary refiner, wherein the second conduit delivers the chemical agent to the primary refiner. | 3 |
BACKGROUND
[0001] This invention relates generally to a method for brightening mechanical pulp.
[0002] Paper pulp typically is subjected to a brightening process prior to paper making. The presence of transition metal ions in paper pulp is known to be detrimental to the brightening process. Chelation techniques, also known as Q stage techniques, have been used to remove transition metal ions from pulp, thereby enhancing brightness levels. Y. Ni et al., Pulp & Paper Canada, vol. 98, T285 (1998). Treatment of pulp with sodium hydrosulfite prior to chelation, known as the Q y stage technique, is believed to improve chelation of metals, thereby further enhancing pulp brightness. However, this technique is less effective at higher pH values, such as those encountered when precipitated calcium carbonate (“PCC”) is used as a filler in a pulp and paper mill.
[0003] The problem addressed by this invention is to find a more effective method for brightening mechanical pulp at high pH values.
STATEMENT OF INVENTION
[0004] The present invention is directed to an improved method for brightening mechanical pulp under neutral or alkaline paper making conditions. The improvement comprises the steps of: (a) separating neutral or alkaline pulp dilution water into a high-solids stream and a neutral or alkaline low-solids stream; and (b) reusing the neutral or alkaline low-solids stream for pulp dilution purposes prior to a bleaching process.
DETAILED DESCRIPTION
[0005] [0005]FIG. 1 is a graph showing the effect of differing levels of hydrosulfite on brightness at varying consistency levels.
[0006] [0006]FIG. 2 is a graph showing the effect of white water components on brightening with 1.2% sodium hydrosulfite.
[0007] [0007]FIG. 3 is a graph showing the effect of temperature on brightness at 60 minutes retention and 3.5% consistency and at varying hydrosulfite levels.
[0008] [0008]FIG. 4 is a graph showing the effect of temperature on brightness at 10 minutes retention and 3.5 % consistency and at varying hydrosulfite levels.
[0009] [0009]FIG. 5 is a graph showing the effect of retention time on brightness at 80° C. and 3.5% consistency and at varying hydrosulfite levels.
[0010] [0010]FIG. 6 is a graph showing the effect of retention time on brightness at 70° C. and 3.5% consistency and at varying hydrosulfite levels.
[0011] Dilution water (i.e. cloudy white water) typically is added to mechanical pulp prior to a bleaching step. In an integrated pulp and paper mill, the dilution water is a recycled stream from the paper making operations. In acid-based mills, the dilution water typically is at a pH from 4 to 5, and contains impurities such as pulp fines, suspended and dissolved solids, fillers and transition metal ions. In a neutral to alkaline paper making environment, i.e., one that utilizes PCC as a filler, the dilution water is at a pH from 6 to 8, and contains impurities such as pulp fines, suspended calcium carbonate, and transition metal ions. Of these impurities, transition metals can be especially troublesome as they can catalyze the decomposition of bleaching chemicals resulting in reduced bleaching efficiency and lower brightness levels. They also tend to increase brightness reversion and thus further contribute to lowering the brightness of bleached pulp. Both reductive and oxidative bleaching chemicals are affected by transition metals. The most commonly used oxidative bleaching chemical is hydrogen peroxide. Reductive bleaching chemicals typically are aqueous reducing agents, including, e.g., dithionite anion, also known as hydrosulfite, borohydrides and bisulfites, and formamidine sulfinic acid.
[0012] The present inventors have determined that use of cloudy white water from neutral to alkaline processes for dilution of pulp decreases the brightness level attainable with reducing agents, such as hydrosulfite. According to this invention, the neutral or alkaline cloudy white water used by the industry for the dilution of pulp prior to a bleaching process can be separated into a high-solids-containing as well as a low-solids-containing stream for treatment to improve the aforementioned bleach process. Separation of the cloudy white water is achieved using any of the methods well-known in the pulp industry for separation of solids, including, e.g., retaining fines on a paper machine wire, processing through a saveall or a clarifier, and flotation or filtration devices. The levels of solids in the low- and high-solids streams are determined by the initial level of solids in the cloudy white water and the method of separation. The amount of solids in the high-solids stream is not critical because this stream can be handled by solids or slurry handling equipment at a variety of solids contents. The high-solids stream can be as much as 30%, or even 40% solids and still be handled as a stream. Moreover, when the high-solids stream is separated by filtration, it is a wet filter cake, which may have an extremely high solids content. The low solids stream contains no more than 5000 ppm of solids, preferably no more than 2000 ppm, more preferably no more than 1000 ppm, still more preferably no more than 500 ppm, still more preferably no more than 250 ppm, and most preferably no more than 100 ppm.
[0013] According to this invention, the use of the low solids stream under neutral or alkaline conditions (pH 6 to 8) minimizes the adverse effects on the brightness of the resulting pulps. The Examples demonstrate that the reduction of the amount of solids in the cloudy white water significantly lowers the levels of transition metals and other impurities in the low solids stream and thereby improves the efficiency of bleaching. Preferably, the pH of the dilution water is from 6.5 to 7.5.
[0014] In one aspect of this invention, the low-solids stream is introduced into a bleaching step. In another aspect of this invention, the low-solids stream is added to the mechanical pulp entering a paper making machine. In one aspect of this invention, the high-solids stream is treated with at least one chelant and at least one reducing agent to produce a treated high-solids stream. Suitable chelants include, e.g., DTPA, STPP, EDTA, and phosphorus-containing chelants, e.g., phosphonate- and phosphonic-acid chelants. In one aspect of this invention, the treated high-solids stream from the process is added to the mechanical pulp entering a paper making machine. In another aspect of this invention, the treated high-solids stream is introduced into a bleaching step. In another aspect of this invention, an untreated high-solids stream is added to the mechanical pulp entering a paper making machine.
[0015] Chemical treatment of the high solids stream recovered from cloudy dilution water from neutral or alkaline processes according to the method of this invention allows recycling of the solids without adverse effects on brightness of the resulting paper and pulps. Without being bound by theory, it is believed that addition of a reducing agent to the solids recovered from the pulp dilution water reduces the valences of the transition metal ions. The reduced valences in turn result in better chelation of transition metals, and treated solids that typically have reduced levels of transition metals, and thus can be introduced into the bleaching and paper making process without adversely affecting pulp brightness.
[0016] It is preferred that the reducing agent is dithionite anion, i.e., hydrosulfite anion. Examples of other reducing agents are borohydride ion and bisulfite ion. Most preferably, the reducing agent is sodium hydrosulfite generated from treatment of sodium bisulfite with sodium borohydride, the latter preferably in the form of a strongly basic aqueous solution, e.g., the product containing 12% sodium borohydride and 40% sodium hydroxide, and sold by Rohm and Haas Company under the name Borol™ solution. Sodium dithionite produced in this manner is known as Borol™-solution-generated hydrosulfite (“GH”).
EXAMPLES
Example 1
Effect of Process Conditions on BGH Brightening
[0017] Pulp and white water used in this study were obtained from a North American mill. The pulp was a chemothermomechanical pulp (cTMP), which was collected after the secondary refiners and prior to the latency chest. The Precipitated Calcium Carbonate (PCC) containing white water (WW) was collected just prior to dilution at the latency chest. Studies were conducted to determine the effect on BGH bleached pulp brightness levels of the following four process variables: retention time, bleaching temperature, and bleaching consistency using either PCC-containing white water (WW) or deionized (DI) water for dilution of the pulp slurry. The hydrosulfite dosage (hydro) was 0-24 lbs./ton BGH at a pH of 10. The raw data for these experiments can be seen in Table 1. Temperatures are in ° C. (Temp.), retention times are in minutes, consistency (“Consist.”) in weight % of pulp in the pulp slurry, deionized water had a pH of 6.5 and PCC-containing white water a pH of 7.5, and brightness is given as a percentage ISO. The pulp was cTMP with a pH of 7.1. Initial pH, (before hydrosulfite addition) and final pH (after hydrosulfite addition and after retention time) are also tabulated for each experiment.
TABLE 1 cTMP Bleaching Results Initial Hydro Final Time Temp. Consist. Water Bright. pH (lb/ton) pH (min.) (° C.) (%) Type (% ISO) 6.9 0 6.8 60 80 3.5 WW 47.4 6.9 8 6.7 60 80 3.5 WW 52.3 6.9 16 6.8 60 80 3.5 WW 54.5 6.9 24 6.8 60 80 3.5 WW 55.5 6.5 0 6.5 60 80 3.5 DI 50.4 6.5 8 6.6 60 80 3.5 DI 56.5 6.5 16 6.7 60 80 3.5 DI 57.8 6.5 24 6.7 60 80 3.5 DI 59.9 6.9 0 6.9 60 70 3.5 WW 46.9 6.9 8 6.9 60 70 3.5 WW 51.9 6.9 16 6.9 60 70 3.5 WW 52.8 6.9 24 6.9 60 70 3.5 WW 54.4 6.5 0 6.5 60 70 3.5 DI 49.8 6.5 8 6.7 60 70 3.5 DI 55.3 6.5 16 6.8 60 70 3.5 DI 57.4 6.5 24 6.7 60 70 3.5 DI 58.8 6.9 0 6.8 10 80 3.5 WW 47.1 6.9 8 6.8 10 80 3.5 WW 50.9 6.9 16 6.8 10 80 3.5 WW 52.7 6.9 24 6.7 10 80 3.5 WW 53.2 6.5 0 6.5 10 80 3.5 DI 50.2 6.5 8 6.6 10 80 3.5 DI 55.0 6.5 16 6.5 10 80 3.5 DI 56.9 6.5 24 6.6 10 80 3.5 DI 57.8 6.9 0 6.9 10 70 3.5 WW 47.4 6.9 8 6.9 10 70 3.5 WW 50.2 6.9 16 6.8 10 70 3.5 WW 51.8 6.9 24 6.9 10 70 3.5 WW 52.3 6.5 0 6.5 10 70 3.5 DI 50.0 6.5 8 6.6 10 70 3.5 DI 53.6 6.5 16 6.7 10 70 3.5 DI 55.7 6.5 24 6.7 10 70 3.5 DI 56.1 7.1 0 7.1 10 80 6.5 WW 47.9 7.1 8 7.0 10 80 6.5 WW 52.5 7.1 16 7.0 10 80 6.5 WW 54.1 7.1 24 6.9 10 80 6.5 WW 55.2 6.8 0 6.8 10 80 6.5 DI 49.7 6.8 8 6.8 10 80 6.5 DI 54.8 6.8 16 6.8 10 80 6.5 DI 56.2 6.8 24 6.7 10 80 6.5 DI 56.0 7.2 0 7.2 10 80 10 WW 47.9 7.2 8 6.7 10 80 10 WW 52.7 7.2 16 6.5 10 80 10 WW 54.0 7.2 24 6.5 10 80 10 WW 56.1 6.9 0 6.9 10 80 10 DI 49.1 6.9 8 6.5 10 80 10 DI 53.5 6.9 16 6.3 10 80 10 DI 55.3 6.9 24 6.3 10 80 10 DI 56.1
[0018] FIGS. 1 - 6 depict the effect on bleached brightness of various combinations of the process conditions investigated. FIG. 1 shows the effect of bleaching consistency and the type of dilution water used on BGH bleached pulp brightness. Traditionally, it has been difficult to obtain a brightness increase at higher consistencies in laboratory-scale studies, although mill experience has shown that brightness increases with increasing consistency. This is believed to be due to the difficulty in effectively mixing pulp and chemicals at medium consistency in the laboratory. Therefore, the fact that the present study showed that the brightness of bleached pulp decreased with increasing consistency when the pulp was diluted with deionized water was not surprising. However, the fact that the brightness of bleached pulp increased with increasing consistency when the pulp was diluted with PCC-containing white water was unexpected. Without being bound by theory, it is believed that PCC-containing white water has a large negative effect on brightness. The decrease in that negative effect at higher bleaching consistency, where there is less PCC-containing white water present because less water is used for dilution relative to low consistency bleaching, has a positive effect on brightness. This positive effect is larger than the negative effect from increased consistency that is usually observed due to poor mixing for laboratory scale bleaching. Table 2 summarizes the averaged effect of changes in consistency, temperature and retention time on brightness in pulp diluted with either deionized water (DI) or PCC-containing white water (WW). The average brightness gains were calculated by taking the average of the brightness gains throughout the response curve of FIG. 1, i.e., from 8 to 24 pounds of BGH per ton of pulp.
TABLE 2 Effect of Changes in Process Conditions on Average Brightness Gains Process Condition Change DI WW Consistency 3.5 to 10.0 −1.8 +1.9 Temperature 70° C. to 80° C. +1.4 +1.0 Retention Time 10 min to 60 min +1.8 +1.8
[0019] Table 3 shows the effect of changing from DI water to PCC-containing white water at two different BGH levels:
TABLE 3 Effect on Brightness of Changing from DI to PCC White Water BGH Level Change in Brightness 8 lbs./ton −3 24 lbs./ton −5
[0020] Table 4 shows the maximum absolute brightness level achieved with each process variable combination tested.
TABLE 4 Maximum Absolute Brightness Level Obtained Brightness Brightness with DI with PCC Time Temp. Consistency water water 60 80 3.5 59.9 55.6 60 70 3.5 58.8 54.4 10 80 3.5 57.8 53.2 10 70 3.5 56.1 52.3 10 80 6.5 56.0 55.2 10 80 10.0 56.1 56.2
[0021] These results demonstrate that the use of PCC-containing white water for pulp dilution has a negative effect on BGH brightening. However, these results also suggest that this effect is mitigated to some degree by adjustment of process conditions, for example, by increasing the bleaching consistency.
Example 2
Fines (Solids) Removal and Reuse of Low-Solids White Water
[0022] [0022]FIG. 2 compares the BGH-bleached pulp brightness of pulp diluted with DI water, PCC-containing white water, the filtrate of PCC-containing white water, and fines that were removed by filtration of PCC-containing white water and re-suspended in DI water. The results show that the removal of solids and reuse of low solids white water for bleaching purposes minimizes the adverse effects of BGH brightening under alkaline or neutral conditions. The results also show that it is the fines portion, which consists of actual pulp fines, undissolved solids, and transition metals in the white water that is responsible for most of the brightness loss. Based on these results, further testing of the fines portion of PCC containing white water was undertaken and is summarized in the following examples.
[0023] Results of transition metal analysis of the pulp, the white water filtrate, and the fines are shown in Table 5.
TABLE 5 Metals Concentration (in ppm) for cTMP & PCC-Containing White Water Portions Al Ca Cu Fe Mg Mn Pulp 17 1760 0.9 40 190 111 PCC Fines 822 96200 7 667 587 183 High solids PCC WW 2 217 0.1 1.2 9 2 Low solids
[0024] By far the largest concentration of metal is 96,200 ppm of calcium, almost 10%, in the fines portion of the white water. This high level results from the presence of precipitated calcium carbonate (PCC) in the white water. It is believed that the white water is detrimental to BGH brightening because the white water introduces large amounts of impurities to the pulp slurry. The high iron concentration is detrimental to hydrosulfite brightening. The high manganese concentration is also of concern, especially in the case of peroxide brightening. Manganese is well known as a catalyst for decomposition of peroxide.
Example 3
Fines Treatment and Re-use
[0025] To reduce the transition metal concentrations, fines were treated by the Qy process. The fines first were treated with 0.1% BGH and then with 0.5% diethylenetriaminepentaacetic acid (DTPA). Experiments were conducted at a pH of 5.5, a consistency of 3.0%, and a temperature of 50° C. for 30 minutes. The Qy treatment is believed to be more effective than the Q treatment, i.e., use of only chelant, because reduction of transition metal valence state by BGH renders the transition metal ions more amenable to chelation. The Qy treatment allows higher brightness levels when using hydrogen peroxide as a brightening agent. Table 6 shows the results from Q and Qy treatments on the fines portion of PCC-containing white water.
TABLE 6 Metal Levels After Q or Qy Treatment of Fines From PCC-Containing White Water (levels in ppm, unless otherwise indicated) Al Ca (%) Cu Fe Mg Mn Q 807 8.23 4.3 668 336 76.1 Qy 726 6.84 3.3 638 312 61.2 Control 821 9.99 3.4 667 504 165
[0026] The results demonstrate that the Qy process enhanced removal of transition metals from the fines portion of PCC white water.
[0027] Table 7 shows the results from Qy treatment on the pulp portion with BGH and DTPA, and from Q treatment with DTPA alone. The metal levels are given in ppm.
TABLE 7 Treatment of cTMP Pulp by Q and Qy Methods Treatment DTPA, % BGH, % Al Cu Fe Mg Mn Q 0.5 — 21 0.7 24 130 9 Q 0.13 — 13 0.8 43 133 48 Qy 0.5 0.1 14 0.7 18 123 6 Qy 0.13 0.1 11 1.1 19 120 44 Control 0 0 17 0.9 40 190 111
[0028] The table demonstrates that good results are obtained for reduction of manganese and iron, both of which are associated with poor brightening with BGH and hydrogen peroxide. Although the difference in manganese concentration is small, Qy treatment produces a lower level of manganese than Q treatment. For iron, the results are more readily apparent. Even at the lower level of DTPA, the iron level is substantially lower for the Qy treatment. It is important to note that this pulp sample was taken at the secondary refiner outlet, prior to addition of mill white water. In reality, the pulp entering the bleach plant would have higher levels of metals from the PCC-containing white water dilution.
[0029] Table 8 shows the results from brightening with BGH the treated pulp described in Table 7. Brightness (B) is given in % ISO, and levels of iron and manganese in ppm. These results demonstrate that at relatively low initial levels of transition metals in pulp, the Qy treatment produces a higher brightness pulp. Thus, Qy treatment would be more effective on pulps with higher initial transition metal concentrations.
TABLE 8 BGH Brightening of Q and Qy Treated cTMP BGH, % Fe Mn B 0.5% DTPA (Q) 1.2 24 9 58.3 0.13% DTPA (Q) 1.2 43 48 57.2 0.5% DTPA + 0.1% BGH (Qy) 1.2 18 6 58.5 0.13% DTPA + 0.1% BGH (Qy) 1.2 19 44 57.4
[0030] Tables 9 and 10 show the results of hydrogen peroxide brightening of pulps treated as shown in Table 7. Peroxide (H 2 O 2 ) bleaching was carried out with a sodium hydroxide dosage of 1.5% for 3% peroxide and 2.0% for 5% peroxide. The sodium silicate dosage was 2.5%, magnesium sulfate dosage was 0.05%, the consistency was 12.0%, the temperature was 80° C. and the bleaching time was 2 hours. The results for % ISO brightness (B) demonstrate that the pulps receiving the Qy treatment display a greater brightness enhancement along with a higher residual peroxide level than those subjected to Q treatment. Transition metal levels are given in ppm, with other measurements given as per cent values.
TABLE 9 Hydrogen Peroxide (P) Brightening of Q and Qy treated cTMP (5.0% H 2 O 2 ) Residual H 2 O 2 Fe Mn B Peroxide 0.5% DTPA (Q) 5.0 24 9 72.9 9.2 0.13% DTPA (Q) 5.0 43 48 71.6 6.3 0.5% DTPA + 0.1% BGH (Qy) 5.0 18 6 73.5 15.1 0.13% DTPA + 0.1% BGH (Qy) 5.0 19 44 71.9 8.4
[0031] [0031] TABLE 10 Hydrogen Peroxide Brightening of Q and Qy Treated cTMP (3.0% H 2 O 2 ) Residual H 2 O 2 Fe Mn B Peroxide 0.5% DTPA (Q) 3.0 24 9 69.5 7.6 0.13% DTPA (Q) 3.0 43 48 67.0 4.3 0.5% DTPA + 0.1% BGH (Qy) 3.0 18 6 69.6 13.2 0.13% DTPA + 0.1% BGH (Qy) 3.0 19 44 67.8 8.1 | The present invention is directed to an improved method for brightening mechanical pulp under neutral or alkaline papermaking conditions. The improvement comprises the steps of: (a) separating neutral or alkaline pulp dilution water into a high-solids stream and a neutral or alkaline low-solids stream; and (b) reusing the neutral or alkaline low-solids stream for pulp dilution purposes prior to a bleaching process. | 3 |
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] This is a continuation of application Ser. No. 10/760,069 entitled “Barrier Movement Operator Having Obstruction Detection” filed Jan. 16, 2004 having inventors Robert Keller and Colin Willmott and which is incorporated herein by reference in its entirety.
BACKGROUND
[0002] The present invention relates to barrier movement operators and particularly to barrier movement operators having improved characteristics for detecting obstructions to the movement of the barrier.
[0003] Barrier movement operators generally comprise an electric motor coupled to a barrier and a controller which responds to user input signals to selectively energize the motor to move the barrier. The controller may also respond to additional input signals, such as those from photo-optic sensors sensing an opening over which the barrier moves, to control motor energization. For example, should a photo optic sensor detect an obstruction present in the barrier opening, the controller may respond by stopping and/or reversing motor energization to stop and/or reverse barrier movement. The controller may also respond to motor speed representing signals by controlling motor energization. Such may be used to stop and/or reverse the movement of a barrier when the motor speed, which represents the speed of movement of the barrier, falls below a predetermined amount as might occur if the barrier has contacted an obstruction to its movement.
[0004] Detecting contact by the barrier with an obstacle by sensing the driving speed of the motor has certain inherent difficulties. The barrier, barrier guide system and the connection between the barrier and the motor all have momentum and all exhibit some amount of flexibility. When the leading edge of a barrier is slowed, it takes time for the inertia of the various parts to be overcome and for the slowing of the barrier to be reflected back to the motor via the flexible (springy) interconnection. Through proper design and construction techniques, such systems have been successfully achieved for response times and contact pressure thresholds to achieve safe operation. However, to achieve ever safer operation involving lower barrier contact forces and more rapid response times, new designs are needed.
[0005] Motors for use with barrier movement operators are generally constructed or selected to operate efficiently and exhibit a motor rotation rate (motor speed) to torque characteristic represented in FIG. 4 . The normal forces on the barrier generally allow the operating motor speed between the marks labeled A and B on FIG. 4 resulting in a relatively flat slope of the speed versus torque characteristic. The “normal” motor having a characteristic as shown in FIG. 4 exhibits a change of motor RPM of approximately 20 RPM per inch-pound of required motor torque. Improvements in obstruction contact times and reduction of obstruction contact forces is difficult with a motor having the characteristics of FIG. 4 because the change of motor RPM is small for the normal range of obstruction forces. A need exists for a motor which operates with a torque to speed characteristic which is enhanced for rapid obstacle detection.
[0006] Improvements in barrier contact obstacle detection may also be achieved by improvements in how sensed motor speed changes are interpreted. Existing barrier movement systems include obstacle detection functions which compare currently measured motor speed with an obstacle indicating threshold. The obstacle indicating threshold generally consists of an expected motor speed minus a constant which defines how much additional speed reduction represents an obstacle rather than a normal variation in operating speed. In some systems an average speed is assumed for the entire movement between open and closed positions and when motor speed falls below the normal speed minus a fixed threshold an obstacle is assumed. In other systems a speed history is determined for door movement by recording measured speeds at several (many) points along barrier travel. When the measured speed falls below the speed history for the same point in barrier travel minus a fixed threshold, an obstacle is assumed. Improvements are needed in obstacle detection to permit fine control of speed changes which indicate an obstruction.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 shows a barrier movement system connected to a vertically moving garage door;
[0008] FIG. 2 is a block diagram of the control apparatus for a barrier movement operator;
[0009] FIG. 3 illustrates circuitry for detecting motor rotation speed;
[0010] FIG. 4 is a graph of motor rotation speed versus required motor torque for existing induction A.C. motors;
[0011] FIG. 5 is a graph of motor rotation speed versus required motor torque for enhanced A.C. induction motor operation;
[0012] FIG. 6 is a diagram of a modified A.C. voltage which may be used to power A.C. motors;
[0013] FIG. 7 is a graph representing motor speed and obstacle detection thresholds;
[0014] FIGS. 8A and B represent the stator and field windings of an A.C. induction motor;
[0015] FIGS. 9A and B represent the rotor of an A.C. induction motor; and
[0016] FIG. 10 is a graph of motor torque versus motor current for normal and one enhanced induction A.C. motor.
DESCRIPTION
[0017] FIG. 1 illustrates the use of a barrier movement operator 10 for vertically moving a garage door. It should be understood that a barrier movement operator as described and claimed herein may be used to move other types of barrier such as gates, window shutters and the like. Barrier movement operator 10 includes a head unit 12 mounted within a garage 14 . The head unit 12 is mounted to the ceiling of the garage 14 and includes a rail 18 extending therefrom with a releasable trolley 20 attached having an arm 22 extending to a multiple paneled garage door 24 positioned for movement along a pair of door rails 26 and 28 . The system includes a hand-held transmitter unit 30 adapted to send signals to an antenna 32 positioned on the head unit 12 and coupled to a receiver as will appear hereinafter. A switch module 39 is mounted on a wall of the garage. The switch module 39 is connected to the head unit by a pair os wires 39 a and includes a command switch 39 b . An optical emitter 42 is connected via a power and signal line 44 to the head unit. An optical detector 46 is connected via a wire 48 to the head unit 12 .
[0018] As shown in FIG. 2 , the garage door operator 10 , which includes the head unit 12 has a controller 70 which includes the antenna 32 . The controller 70 includes a power supply 72 which receives alternating current from an alternating current source, such as 110 volt AC, at a pair of conductors 132 and 134 , and converts the alternating current into DC which is fed along a line 74 to a number of other elements in the controller 70 . The controller 70 includes and rf receiver 80 coupled via a line 82 to supply demodulated digital signals to a microcontroller 84 . The microcontroller 84 includes a non-volatile memory, which non-volatile memory stores set points and other customized digital data related to the operation of the control unit. An obstacle detector 90 , which comprises the infrared emitter 42 and detector 46 is coupled via a bus 92 (which comprises lines 44 and 48 ) to the microcontroller. The obstacle detector bus 92 includes lines 44 and 48 . The wall switch 39 is connected to supply signals to and is controlled by the microcontroller. The microcontroller, in response to switch closures, will send signals over a relay logic line 102 to a relay logic module 104 which connects power to an alternating current motor 106 having a power take-off shaft 108 . A tachometer 110 is connected to shaft 108 and provides a tachometer signal on a tachometer line 112 to the microcontroller 84 . The tachometer signal being indicative of the speed of rotation of the motor. The tachometer 110 may comprise an interrupter wheel represented at 115 ( FIG. 3 ) connected to rotate with the motor shaft 108 . A light source 128 and light receiver 127 detect rotation of the shaft by detecting successive passings of a plurality of light blocking apparatuses 117 and reporting to controller 84 via communication path 112 . Microcontroller 84 can then determine current motor speed by calculating the period between successive light blockages. It should be mentioned that other means for detecting rotation rate may also be employed such as a cup shaped interrupter with equally spaced apertures therethrough to successively block and pass light between source 128 and detector 127 . The signals on conductor 112 from tachometer 110 may also be used to identify the position of the barrier when used with a pass point arrangement or position detector shown at 120 , which operation is known in the art.
[0019] The barrier movement operator of FIG. 1 begins to move the barrier in response to a user pressing button 39 B of wall control 39 or pressing a transmit button of transmitter 30 . Generally, when movement begins the barrier is in the open or closed positions. When a command to move the barrier is received, the barrier driven toward the other limit. In the present embodiment the controller 10 tracks the position of the barrier in response to signals from tachometer 110 and formulates operations based on that sensed position. The controller also may respond to signals from optical detector 90 representing a possible obstruction by reversing the direction of a downwardly traveling barrier.
[0020] The barrier movement operator of FIG. 1 also responds to sensed information about the forces required to move the barrier to control further barrier movement. For example, as the barrier is moved, motor speed is continuously checked as an indication of the forces being required to move the barrier. FIG. 4 is a graph of a normal motor showing motor rotation speed versus motor output torque. As the forces required to move the door increase the motor slows. The converse is also true. The predictable nature of speed change versus applied forces allows the motor speed to be used as an indication of such things as the barrier contacting an obstruction.
[0021] Barrier movement operators have been constructed which respond to the motor speed falling below a fixed value by assuming that the barrier has contacted an obstruction and, accordingly, stop or reverse the travel of the barrier. More sophisticated systems have been designed which record measured motor speed at a number of barrier positions establish obstruction threshold histories for different barrier positions. FIG. 7 illustrates one such thresholding system in which 6 thresholds labeled 50 , 52 , 54 , 56 , 58 and 60 are shown. It should be mentioned that in FIG. 7 motor speed is represented by the period between successive light blockages from an interrupter wheel and as such higher on the graph of FIG. 7 represents lower motor speed. During movement of the barrier, a number of different motor speeds are sensed as represented by the measured speed line. Zones of interest are then selected and a value representing the minimum speed in each zone is recorded. In FIG. 7 , the minimum speed in a first zone is represented at 51 , a second at 53 and others at 55 , 57 , 59 and 61 . A predetermined speed difference value may then be subtracted from each minimum speed to establish the overall threshold for the zone. The references 50 , 52 , 54 , 56 , 58 and 60 represent the per zone thresholds. After the zone thresholds have been learned (or updated) whenever measured speed falls below the zone threshold an obstruction is assumed and the barrier is stopped or reversed.
[0022] As shown in FIG. 7 each minimum threshold is a fixed amount different from the minimum speed in the zone as represented by the couplets 50 - 51 , 52 - 53 , 54 - 55 and 56 - 57 . In the present embodiment, particular zones can be configured to be more sensitive than other zones. For example, the period (speed) difference between 57 and 56 is the same as the period (speed) difference between all other couplets toward the open representing left of the graph. Thus, all zones from 56 - 57 to the left are of substantially equal sensitivity. The zone represented by the couplet 58 - 59 is more sensitive because less speed difference between the measured minimum 59 and the threshold 58 exists than between the other couplet to the left. As can be seen in FIG. 7 the most sensitive zone is near the closed position and advantageously is placed within 18 inches of the closed position.
[0023] Other improvements to obstruction detection are made by the presently disclosed barrier movement system. FIG. 4 represents the speed versus torque characteristic for a normal motor. As can be seen the slope of the line from A to B which represents a normal operating range, an increase of required torque of one ft. lb. results in a motor speed change of only about 12-13 RPM. This is a relatively small change to be rapidly detected, particularly in the real environment as represented by the measured speed line of FIG. 7 . FIG. 5 represents in the speed versus torque characteristic of a motor and its driving apparatus which is enhanced to improve motor speed change. The slope of the line between points A 1 and B 1 on FIG. 5 results in a change of speed of approximately 47 to 48 RPM per inch-pound of torque thus making speed changes more easily detected.
[0024] A characteristic as shown in FIG. 5 can be achieved by producing a motor with the appropriate parameters. FIGS. 8A and 8B are views of a field winding/stator of an induction motor. FIGS. 9A and 9B represent the induction rotor of such a motor. The rotor of an AC induction motor includes a plurality of ferris metal rotor lamination formed together into a cylinder as represented at 62 . The rotor laminations have a plurality of regularly spaced apertures which are arranged to extend from one end of the rotor cylinder at an angle as represented by 64 . The apertures are filled with an electrically conductive non-ferris metal such as aluminum. Finally end rings 64 are formed at the ends of the diagonal conductive lines 64 from non-ferris electrical conductors to provide conductive paths between the diagonals 64 . Due to current induced by AC applied to the field coils, magnetic fields are produced in the rotor which cause rotation.
[0025] Normally motors are designed to provide very low resistance in the cross paths 64 and the end rings 66 resulting in a characteristic as shown in FIG. 4 . In the present embodiment, however, the resistances have been increased which results in an enhanced characteristic as shown in FIG. 5 . In a preferred embodiment the resistance increase was produced by using smaller than normal amounts of non-ferris metal for conductors 64 and 66 . The results could also be achieved by fabricating the conductors 64 and 66 from non-ferris material having greater internal resistance.
[0026] In the above discussion the enhanced characteristic ( FIG. 5 ) was achieved during motor fabrication or selection. Such can also be achieved by selective coupling of incoming AC power to the motor 106 . In FIG. 2 incoming AC power is connected to conductor 132 and 134 which are in turn connected to a power control circuit 114 . An output of power control circuit 114 is used to power the motor. Power control circuit 114 selectively blocks portions of each cycle of the incoming sinusoidal AC wave form shown in FIG. 6 to the motor 106 via relay logic 104 . The wave form of FIG. 6 is achieved by a “light dimmer” circuit in power control which is preset to pass a predetermined percentage e.g., 60 percent of each sine wave cycle. Energization of an AC induction motor with a wave form shown in FIG. 6 results in a characteristic as shown in FIG. 5 . Greater control over the A.C. wave form applied to the motor 106 by using a power control circuit of the type described in U.S. patent application Ser. No. 10/622,214 filed 18 Jul. 2003 which is connected to microcontroller 84 via a control line 118 . Such greater control might include skipping entire cycles of applied A.C. Also the wave form of FIG. 6 may be reproduced using high frequency e.g., 1 KHZ duty cycle control.
[0027] The preceding embodiment measured rotation speed of the motor to detect possible obstructions because motor speed represents present torque requirements of the motor. (See FIGS. 4 and 5 ) The current drawn by an induction A.C. motor also represents the present torque requirements of the motor. As the force requirements increase so does the current applied to the motor. The motor current may be sensed by an optional current sensor 130 connected to the A.C. inputs of the relay logic 104 . ( FIG. 2 ) This relationship is shown in FIG. 10 as 203 for a “normal” motor and 201 for a motor enhanced by the above described motor modifications and driving techniques. When motor current is sensed to detect possible obstructions, the enhanced characteristic 201 provides more rapid and certain obstruction detection.
[0028] While there has been illustrated and described particular embodiments of the present invention, it will be appreciated that numerous changes and modifications will occur to those skilled in the art, and it is intended in the appended claims to cover all those changes and modifications which fall within the true spirit and scope of the present invention. | A barrier movement operator includes an A.C. motor having a rotatable rotor connected to a barrier for movement thereof. A sensing apparatus generates motor signals representing an operational variable of the motor. The movement of the barrier is controlled by a controller, which responds to the motor signals by selectively stopping rotation of the rotor or reversing the rotation of the rotor. A power control arrangement provides energizing power to the motor by receiving AC power input substantially in the form of a sine wave and conducts portions of successive cycles of the sine wave of the received AC power to the motor to enhance the sensed operational variable to torque characteristic of the motor. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates generally to the field of material transport systems and particularly to a web transport system.
Material transport systems move various types of material from one location to another. Some material transport systems are used to move thin materials. An example of a thin material is a filmstrip or filmstrip and paper carrier combination or web.
When a filmstrip is printed for the first time (first order), the various 24 and 36 exposure filmstrips are joined end to end to form a continuous constant width filmstrip roll. In order to make photographic printers more efficient during reorder operations, the various frames of a filmstrip, that a customer wants reprinted are attached to a paper carrier. The paper carrier forms a roll containing many frames, that are randomly attached to one side of the paper carrier. Thus, in certain roll locations there will be filmstrip and a paper carrier and in other roll locations there will only be a paper carrier. Hence, the width of the filmstrip paper carrier combination varies. The paper carrier filmstrip combination is able to be rapidly moved through the printer. Whereas, if the filmstrip was not connected to a paper carrier, individual frames on four frame filmstrips would have to be moved through the printer.
Rollers may be used to guide a first order filmstrip by contacting either edge of the filmstrip. However, if the filmstrip is connected to a paper carrier, the guide roller may only contact the paper carrier portion of the roll, since the filmstrip segments are too flimsy and are intermittent.
The lateral position of the filmstrip and the filmstrip paper carrier combination needs to be accurately controlled to permit the bar code on the filmstrip and/or the code on the paper carrier to be read. Devices contained within the printer use the information contained in the above codes to set or adjust various photographic printer parameters to produce better quality prints. Thus, precise lateral placement of the filmstrip and filmstrip paper carrier combination is necessary for proper scanning, printing and transport operations.
One of the methods utilized by the prior art to obtain accurate lateral positioning of a filmstrip and paper carrier combination was to urge one edge of the paper carrier against a guiding member having a fixed lateral position. The filmstrip paper carrier combination was very thin. Thus, the filmstrip paper carrier combination did not support significant lateral locating forces without buckling.
Buckling caused inaccurate edge reading of the filmstrip. The buckling of the filmstrip and paper carrier combination was reduced by increasing the lateral column strength of the paper carrier. The lateral column strength of the paper carrier was increased by curving the paper carrier around a transverse axis. The above transverse axis curvature required a change in the filmstrip paper carrier direction from before the guide to after the guide. Thus, additional rollers were needed to change the direction of travel of the filmstrip paper carrier combination to accurately laterally position the filmstrip and paper carrier.
If the filmstrip and filmstrip paper carrier combination travels a large distance, additional rollers are needed to accurately control the lateral position of the filmstrip and the filmstrip paper carrier combination.
If the speed of the filmstrip moving through the photographic printer was increased above 18 inches per second, prior art rollers had difficulty in accurately controlling the lateral position of the filmstrip. The prior art difficulty in accurately controlling the lateral position of the filmstrip was amplified on reorder.
SUMMARY OF THE INVENTION
The present invention overcomes the disadvantages of the prior art by providing a device: that accurately establishes the lateral position of a filmstrip and paper carrier combination (web) or any other web configuration at a particular longitudinal location; that is capable of moving a filmstrip and paper carrier combination a large distance without adding additional rollers; and that reduces buckling of the filmstrip and paper carrier combination.
The foregoing is achieved by providing:
a longitudinal web support surface that is curved in its transverse direction concave towards the web;
a guide extending longitudinally along the surface; and
a roller positioned against the surface, the roller will be deformed when rotated and urge a web laterally against the guide so that the web will conform to the curvature of the surface to increase the lateral column strength of the web.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective representation of a filmstrip and paper carrier being positioned by the apparatus of the invention;
FIG. 2 is a perspective representation of the apparatus shown in FIG. 1, wherein roller 11 is driven by a motor;
FIG. 3 is a sectional view of roller 11 and surface 16;
FIG. 4 is a sectional view of roller 11 and surface 16 showing a preformed crease in paper carrier 19;
FIG. 5 is a perspective representation of an alternate embodiment of the invention; and
FIG. 6 is a perspective representation of another alternate embodiment of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings in detail and more particularly to FIG. 1, the reference character 11 represents a canted or conically shaped roller. The canted roller functions for only one direction of web transport whereas the conical roller provides the lateral web position function in both direction of longitudinal web transport. Roller 11 may be constructed from any compliant elastomeric material, i.e., urethane, polypropylene, etc. The durometer of roller 11 is between 20 and 80 Shore A. Nut 10 and hub 12 allow roller 11 to rotate on one end of shaft 13. The other end of shaft 13 is connected to block 14 by pivot 9. Block 14 is connected to plate 8. Positioned under roller 11 is contoured surface 16, of plate 8. Flat surface 29 of plate 8 is tangent to surface 16. The location of the tangent is approximately at the location where roller 11 no longer presses paper carrier 19 against surface 16. Lateral edge guide 17 is connected to surface 16. Filmstrip 18 will move along surface 29 and paper carrier 19 will pass between surface 16 and roller 11. Rollers 30 will move filmstrip 18 and paper carrier 19 in the direction shown by arrow A. Roller 11 and attachments thereto may be freely pivoted about vertical axis y to allow paper carrier 19 transport direction to self align to drive rollers 30 without tearing stresses in paper carrier 19. Spring 15 is connected to plate 8 and shaft 13. Spring 15 places a downward load on paper carrier 19 through roller 11. The aforementioned load deforms roller 11 in such a manner that the deformation and rotation of roller 11 will cause paper carrier 19 to conform to the curvature of surface 16 and the edge of paper carrier 19 will be pushed against lateral edge guide 17. The lateral column strength of paper carrier 19 is increased by forcing paper carrier 19 to adapt to the concave shape of contoured surface 16.
At the longitudinal location of lateral edge guide 17, surface 16 has a transverse curvature, concave, toward paper carrier 19. The axis of curvature of surface 16 is parallel to arrow A in the transverse region between roller 11 and lateral edge guide 17. The lateral force applied to the relatively thin filmstrip 18 and paper carrier 19 will cause paper carrier 19 to conform into contoured surface 16 where carrier 19 is rigidly supported against further deformation and thus receives a substantial degree of lateral direction compression strength. At the same time as the above is happening filmstrip 18 will move in direction A along surface 29.
FIG. 2 depicts the embodiment shown in FIG. 1, with motor 31 replacing rollers 30. Motor 31 is coupled to shaft 13 and power source 32 supplies power to motor 31. Motor 31 will rotate shaft 13 and roller 11 will move filmstrip 18 and paper carrier 19 in the directions shown by arrow A. Spring 15 places a downward load on paper carrier 19 through roller 11. The aforementioned load deforms roller 11 in such a manner that the deformation and rotation of roller 11 will cause paper carrier 19 to conform to the curvature of surface 16 and the edge of paper carrier 19 will be pushed against lateral edge guide 17. The lateral column strength of paper carrier 19 is increased by forcing paper carrier 19 to adapt to the shape of contoured surface 16.
At the longitudinal location of lateral edge guide 17, surface 16 has a transverse curvature, concave, toward paper carrier 19. The axis of curvature of surface 16 is parallel to arrow A in the transverse region between roller 11 and lateral edge guide 17. The lateral force applied to the relatively thin filmstrip 18 and paper carrier 19 will cause paper carrier 19 to conform into contoured surface 16 where carrier 19 is rigidly supported against further deformation and thus receives a substantial degree of lateral direction compression strength. At the same time as the above is happening filmstrip 18 will move in direction A along surface 29.
FIG. 3 is a sectional view depicting roller 11 and surface 16 of FIG. 1. Roller 11 is connected to shaft 13 by hub 12 and nut 10 and paper carrier 19 is placed between roller 11 and surface 16. Lateral edge guide 17 and surface 16 form an angle B. Angle B is obtuse to prevent escape of the edge of paper carrier 19 for example between 90 and 100 degrees. The radius of curvature R of surface 16 is between one inch and ten inches.
FIG. 4 is the same sectional view of roller 11 and surface 16 of FIG. 2. However, in this view paper carrier 19 is shown with a preformed crease 20. Preformed crease 20 may be formed by operator carelessness, i.e., filmstrip 18 and paper carrier 19 are dropped and someone steps on paper carrier 19. When preformed crease 20 passes between roller 11 and edge guide 17, the severity of crease 20 would be increased by the lateral force applied by roller 11 to paper carrier 19 resulting in buckle failure. The above condition would ultimately severely damage paper carrier 19 and eliminate the proper lateral location of paper carrier 19. Crease 20 may be flattened by the alternate embodiments of this invention depicted in FIGS. 5 and 6.
FIG. 5 shows the addition of a fixed upper constraint guide 21 to shaft 13 of FIG. 1. Guide 21 comprises: a lower plate 22, that is positioned above surface 16; and a side plate 23, that is perpendicular to plate 22. Side plate 23 is connected to shaft 13 by bolt 25. Paper carrier 19 will be positioned between guide 21 and surface 16. As paper carrier 19 enters guide 21, plate 22 will flatten any pre-formed creases that exist in carrier 19 and prevent an increase in the crease height of the pre-formed crease.
FIG. 6 replaces roller 11 of FIG. 1, with a roller and rotation assembly 26. Assembly 26 comprises: roller 27, and member 28. Hub 12 and nut 10 holds assembly 26 against one end of shaft 13. Member 28 may be constructed from any compliant material, i.e., urethane, polypropylene, etc., or from any rigid material i.e., aluminum, thermoplastic, etc. The durometer of roller 27 and volume of rotation 28 is between 20 and 80 Shore A. Roller 27 may be conically, canted or cylindrically shaped and volume of rotation 28 may be contoured to the shape of surface 16.
Paper carrier 19 will be positioned between rotation assembly 26 and surface 16. As paper carrier 19 approaches assembly 26, substitute member 28 will flatten any pre-formed creases that exist in carrier 19 and prevent an increase in the crease height of the pre-formed crease.
The above specification describes a new and improved straight through lateral constraint device. It is realized that the above description may indicate to those skilled in the art additional ways in which the principles of this invention may be used without departing from the spirit. It is, therefore, intended that this invention be limited only by the scope of the appended claims. | A system for establishing the lateral position of a web without requiring the web path to change direction. The system utilizes a support surface that is curved in its transverse direction concave towards the web, a guide extending longitudinally along the surface, and a roller that is positioned against the support surface so that the web will be urged laterally against the guide and will conform to the curvature of the surface, thereby increasing the lateral column strength of the web. | 6 |
GOVERNMENT INTERESTS
This invention was made with government support under grant number CTS-9523993 awarded by the National Science Foundation. The government has certain rights in this invention.
FIELD OF THE INVENTION
The present invention relates to the synthesis of hydrogen peroxide, and more particularly, to the synthesis of hydrogen peroxide without the use of an organic solvent.
BACKGROUND OF THE INVENTION
Hydrogen peroxide (H 2 O 2 ) is often considered to be a “green” material, in that it is increasingly used to replace chlorine-containing reagents in paper bleaching and in water purification. For this reason, as well as others, hydrogen peroxide production is estimated to increase steadily through the beginning of the next century.
The production of hydrogen peroxide is a mature process in that the general procedure has not changed appreciably in twenty years. Indeed, recent research publications in the area of hydrogen peroxide synthesis are somewhat scarce. Typically, hydrogen peroxide is generated in a two-step process, wherein hydrogen is first reacted with a 2-alkyl anthraquinone (usually 2-ethyl or 2-amyl anthraquinone) in an organic solvent to produce the corresponding tetrahydroquinone (2-alkyl tetrahydroquinone). The reaction is catalyzed by a simple palladium-on-alumina catalyst. Conditions for this reaction are typically 30 to 70° C. with hydrogen pressures up to 300 psi. Given the nature of the reactants, the reactor contains three phases (gas, liquid, and solid catalyst) and previous work has shown that the reaction is completely mass transfer limited, such that the rate of the reaction is essentially the rate at which hydrogen diffuses into the liquid phase. Partly as a result of this inefficiency of hydrogen use, side reactions (hydrogenation of one or both of the aromatic rings) also occur, and byproducts build up during repeated cycling of the anthraquinone. These byproducts must periodically be removed and treated. The organic solvent employed is typically a mixture of an aromatic (a good solvent for the anthraquinone) and a long-chain alcohol (a good solvent for the hydroquinone).
The second step of the process involves oxidation of the hydroquinone, regenerating the anthraquinone and producing hydrogen peroxide. Here the catalyst is retained in the first reactor, and the solution of alkyl anthraquinone, alkyl tetrahydroquinone and organic solvent (the working solution) is transferred to the second reactor, where the hydroquinone is reacted with oxygen (as air or oxygen). This reaction is uncatalyzed. Similar to the first reaction, the second reaction is mass transfer limited by the rate at which oxygen can diffuse from the gas to liquid phases. Finally, the hydrogen peroxide is stripped from the organic solvent via liquid-liquid extraction with water and sold as an aqueous mixture (usually 30 to 50%).
Because the final step in the production of hydrogen peroxide involves a liquid-liquid extraction between aqueous and organic phases, the final product is contaminated to some extent by the organic phase. Given that H 2 O 2 is promoted as a green reagent for paper production, and is also used in water purification, the organics in the final product must be minimized. Significant effort is thus made to strip the organic contaminants from the product.
It is, therefore, very desirable to develop reactants and processes for the synthesis of hydrogen peroxide that minimize or eliminate the use of organic solvents.
SUMMARY OF THE INVENTION
In general, the present invention provides a method for synthesizing hydrogen peroxide, comprising the steps of:
synthesizing an analog of anthraquinone that is miscible with (in the case of a liquid analog) or soluble in (in the case of a solid analog) carbon dioxide;
reacting the analog of anthraquinone with hydrogen in carbon dioxide to produce a corresponding analog of tetrahydroquinone; and
reacting the analog of tetrahydroquinone with oxygen to produce the hydrogen peroxide and regenerate the analog of anthraquinone.
Preferably, the regenerated analog of anthraquinone is recycled for future use.
The step of synthesizing an analog of anthraquinone that is miscible in carbon dioxide preferably comprises the step of attaching to anthraquinone at least one modifying or functional group that is relatively highly soluble in CO 2 (“CO 2 -philic”). The miscibility/solubility of the resulting analogs of anthraquinone are several orders of magnitude greater at the operating pressures of the present invention than the solubility of 2-alkyl anthraquinone in carbon dioxide at pressures equal to or below 5000 psi. Alkyl-anthraquinones used in the commercial synthesis of hydrogen peroxide do not exhibit appreciable solubility in carbon dioxide at pressures below 5000 psi. In that regard, a number of studies have explored the solubility of alkyl-functional anthraquinones in carbon dioxide and found generally that the system exhibits solid-fluid phase behavior with maximum solubilities of approximately 10 −2 mM. See, for example, Joung, S. N., Yoo, K. P., J. Chem. Eng. Data , 43, 9 (1998). Coutsikos, P., Magoulos, K., Tassios, D., J. Chem. Eng. Data , 42, 463 (1997). Swidersky, P., Tuma, D., Schneider, G. M., J., Supercrit. Fl ., 9, 12 (1996). ibid , 8, 100 (1995).
A liquid-liquid phase envelope is preferably formed in the functionalized anthraquinone-carbon dioxide systems of the present invention at relatively moderate pressures. The operating pressure at which the analogs of anthraquinone (and preferably the analogs of hydroquinone) are reacted in carbon dioxide is preferably no greater than approximately 5000 psi. More preferably, the operating pressure is no greater than approximately 3000 psi. Even more preferably, the operating pressure is no greater than approximately 2500 psi. Most preferably, the operating pressure is no greater than approximately 1500 psi. The operating pressure at which the analogs of anthraquinone are reacted with hydrogen (and, preferably, the operating pressure at which the analogs of hydroquinone are reacted with oxygen) is preferably chosen such that it is above the cloud point curve (and, preferably, above the maximum of the cloud point curve) in the liquid-liquid phase envelop (or liquid-fluid phase envelope when operating at supercritical conditions). In the region above the cloud point curve, single-phase behavior is observed.
The operating temperature of the present reactions is preferably between approximately 0° C. and approximately 100° C. The operating temperature of the present reactions is more preferably between approximately 20° C. and approximately 40° C. Most preferably, the operating temperature of the present reactions is approximately 25° C. (room temperature).
Preferably, the CO 2 -philic functionalized anthraquinones and the corresponding hydroquinones of the present invention exhibit reactivity similar to the 2-alkyl anthraquinone and hydraquinones used in the current commercial synthesis of hydrogen peroxide. Indeed, the kinetic rate constants calculated for the oxygenation of the functionalized anthraquinones of the present invention were found to be approximately ten time greater than anthraqinone. The use of CO 2 -philic groups to increase the solubility of a molecule in carbon dioxide is also discussed in U.S. Pat. No. 5,641,887, the disclosure of which is incorporated herein by reference.
In general, the analog of anthraquinone preferably has the formula:
At least one of R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , and R 8 (corresponding to the 1, 2, 3, 4, 5, 6, 7, and 8 carbons on the anthraquinone ring structure) is a modifying group or functional group that is miscible/souble in carbon dioxide. Attachment of one or more such CO 2 -philic groups to anthraquinone results in an analog of anthraquinone that is miscible/soluble in carbon dioxide. In that regard, R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , and R 8 are preferably, independently, the same or different, H, R C or R S R C , wherein R S is a connector or a spacer group and R C is a fluoroalkyl (fluorinated alkyl) group, a fluoroether (fluorinated ether) group, a silicone group, an alkylene oxide group, a phosphazene group or a fluorinated acrylate group. At least one of R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , and R 8 is not H. Preferably, R C is a fluoroalkyl group, a fluoroether group or an alkylene oxide group. More preferably, R C is a fluoroether group or an alkylene oxide group.
The spacer group, R S , when present, can simply be a connective group used to attach a CO 2 -philic group to anthraquinone or can additionally act to space the CO 2 -philic group away from the anthraquinone. The spacer group is preferably a group which provides a simple synthetic route to achieve the desired analog of anthraquinone without substantially adversely affecting the miscibility of the analog of anthraquinone in carbon dioxide or the reactivity of the analog of anthraquinone and the corresponding hydraquinone in the synthesis of hydrogen peroxide. For example, the spacer group can be an alkylene group, an amino group, an amido group, an ester group or an alkyl ester group. As used herein in connection with R S , the term “alkylene group” refers to a linear or branched alkylene group. A linear alkylene group, for example, has the formula —(CH 2 ) n —. As used herein in connection with R S , the term “amino group” refers to a secondary amino group having the formula —NH—or a tertiary amino group having the formula —NR 11 H—, wherein R 11 can generally be any substituent that doesn't interfere with the reactivity of the desired analog. For example, R 11 can be an alkyl group. As used herein in connection with R S , the term “amido group” refers to secondary amido having the formula —NHCO—, or a tertiary amido group having the formula —NR 11 CO—wherein R 11 is as defined above. As used herein in connection with R S , the term “ester group” refers to a group having the formula —OCO—. As used herein in connection with R S , the term “alkyl ester group” refers to a group having the formula —R 12 OCO—, wherein R 12 is an alkyl group. The spacer group itself need not be CO 2 -philic. If it is desired to use the spacer group to space the CO 2 -philic group away from the anthraquinone ring structure, an alkalene group is preferably used, either alone or in combination with another connective group.
The total molecular weight of the CO 2 -philic groups Rc attached to the analog of anthraquinone is preferably between approximately 200 and approximately 7500 to make the analog of anthraquinone miscible/soluble in carbon dioxide. One or more CO 2 -philic groups can be attached to the anthraquinone ring structure. For example, each of R 2 , R 3 , R 6 , and R 7 , can comprise a perfluoroalkyl group having a molecular weight of 50. More preferably, the total molecular weight of the CO 2 -philic groups is between approximately 500 and approximately 5000. Most preferably, the total molecular weight of the CO 2 -philic groups is between approximately 500 and approximately 1500.
The fluoroalkyl groups of the present invention are preferably linear perfluoroalkyl groups having the formula/repeat group:
—(CF 2 )g—.
wherein g is an integer.
The fluoroether groups of the present invention are preferably perfluorinated and have the formula/repeat group:
wherein each of x, y and z is an integer greater than or equal to 0 and at least one of x, y and z is not equal to 0.
The silicone groups of the present invention preferably have the formula/repeat group(s):
wherein R 9 and R 10 are chosen to not substantially affect the CO 2 -philic nature of the silicone group or the reactivity of the functionalized analogs of anthraquinone. R 9 and R 10 may, for example, be, independently, the same or different, H, an alkyl group, an aryl group, an alkenyl group, or an alkoxyl group, and wherein b is an integer. Preferably, R 9 and/or R 10 is a fluoroalkyl group.
The alkylene oxide groups of the present invention preferably have the formula/repeat group:
wherein d is an integer and e is an integer.
The fluorinated acrylate groups of the present invention preferably have the formula/repeat group:
wherein g and j are integers.
The phosphazine groups of the present invention preferably have the formula/repeat group:
wherein m is an integer and R 9 and R 10 are as defined above.
The oxidation of the hydroquinone of the present invention preferably takes place in carbon dioxide at substantially the same pressure as the hydrogenation reaction. The hydrogen peroxide product of the present invention is preferably recovered via a liquid-liquid extraction between the carbon dioxide phase and an aqueous phase. The liquid-liquid extraction is preferably conducted without significantly reducing the operating pressure. Likewise, the carbon dioxide is preferably recycled to the extractor without a significant drop in pressure. Such a process for separation/recovery of hydrogen peroxide product avoids the high costs associated with recompression, while taking full advantage of carbon dioxide's green properties in running a contamination-free liquid-liquid extraction between a carbon dioxide phase and an aqueous phase.
Moreover, using carbon dioxide as the solvent for the process of the present invention allows one to generate a single phase system of hydrogen plus anthraquinone (for the first reaction of the synthesis), or oxygen plus tetrahydroanthraquinone or tetrahydroquinone (for the second reaction of the synthesis). It is known that hydrogen is completely miscible with carbon dioxide above a temperature of approximately 31° C. Hydrogen and carbon dioxide have been found to not form separate phases under the operating conditions of the present invention. The reactions can thus be carried out without the mass transfer limitation of the current commercial process for the synthesis of hydrogen peroxide, suggesting that one could operate more efficiently, using less hydrogen and/or at lower temperatures, while producing fewer byproducts.
Furthermore, the operating pH for the stripping operation to recover the hydrogen peroxide from the organic phase into the aqueous stream in the current commercial process for the synthesis of hydrogen peroxide is preferably approximately 3.0 to partition the hydrogen peroxide into the aqueous phase. Because the carbon dioxide of the present invention dissolves in water to form carbonic acid, the pH of the water in the presence of high pressure carbon dioxide is approximately 3.0, assisting in partitioning the hydrogen peroxide into the aqueous phase.
The present invention also provides a chemical compound having the formula:
wherein R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , and R 8 are as described above.
Further, the present invention provides a chemical compound having the formula:
wherein R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , and R 8 are as described above.
Still further, the present invention provides method for synthesizing hydrogen peroxide, comprising the steps of:
synthesizing an analog of anthraquinone having the formula:
wherein R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , and R 8 are as described above;
reacting the analog of anthraquinone with hydrogen to produce a corresponding tetrahydroquinone having the formula;
reacting the tetrahydroquinone with oxygen to produce the hydrogen peroxide and regenerate the analog of anthraquinone.
It has been found experimentally that analogs of anthraquinone functionalized with the CO 2 -philic functional groups of the present invention are typically liquids at relatively low temperatures and pressures. For example, anthraquinones functionalized with fluoroether groups of the present invention are typically liquid at room temperature and one atmosphere pressure. Unlike the current commercial process using 2-alkyl anthraquinone (a solid), one can generate hydrogen peroxide from the liquid functionalized analogs of anthraquinones of the present invention without the use of any solvent (including carbon dioxide). In such a process, the liquid analog of anthraquinone is reacted with hydrogen in the first reaction to produce the corresponding hydroquinone. The corresponding hydroquinone is then oxidated as described above to produce hydrogen peroxide. The hydrogen peroxide product is preferably recovered via liquid-liquid extraction with an aqueous phase. The CO 2 -philic groups of the present invention generally reduce the solubility of the analogs of anthraquinone in water, typically rendering the anthraquiqone very hydrophobic and greatly reducing contamination of the aqueous phase therewith (as compared to the current commercial process) during extraction of the hydrogen peroxide product. Synthesizing hydrogen peroxide with a liquid analog of anthraquinone and without solvent reduces equipment costs as compared to synthesis in carbon dioxide, but, unlike the process in carbon dioxide, the oxidation and hydrogenation reaction would be mass-transfer limited.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates an asymmetric cloud point curve for a functionalized anthraquinone-carbon dioxide system.
FIG. 2 illustrates the effect of functional group length upon the phase behavior of an analog of anthraquinone.
FIG. 3 illustrates the effect of functional group length upon the phase behavior of another analog of anthraquinone.
FIG. 4 illustrates the effect of the identity of a spacer group and the position of the functional group upon the phase behavior of an analog of anthraquinone.
FIG. 5 illustrates the effect of the position of the functional groups upon the phase behavior of a difunctionalized analog of anthraquinone.
FIG. 6 illustrates the hydrogenation of an analog of anthraquinone as monitored by UV spectroscopy.
FIG. 7 illustrates the effect of the length of molecular weight of the CO 2 -philic functional group upon the diffusion coefficient.
FIG. 8 illustrates one embodiment of a reactor system of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Carbon dioxide has received significant scientific interest over the past 15 years because it is considered a “green” alternative to conventional organic solvents. Carbon dioxide is inexpensive (approximately $80/ton, 1-2 orders of magnitude less than conventional solvents), non-flammable, not currently regulated as a volatile organic chemical by the US EPA, and not regulated by the U.S. FDA in food or pharmaceutical applications. The latter advantage has lead to the commercialization of several large (greater than 50 million pounds per year) food processing ventures using carbon dioxide.
Carbon dioxide's inherent “green” properties make it particularly desirable for use in liquid-liquid extraction from water. While any organic solvent will contaminate water to a certain degree in a liquid-liquid extraction, in the case carbon dioxide this “contamination” obviously does not require remediation. Moreover, use of carbon dioxide as a solvent in conjunction with gaseous reactants can eliminate certain transport limitations to reaction.
Although carbon dioxide possesses distinct advantages as a solvent, it also exhibits a number of disadvantages which have limited commercial applications, for the most part, to food processing and polymer foam production. First, use of carbon dioxide (in either the liquid or supercritical state) requires the use of elevated pressures (the vapor pressure of carbon dioxide at room temperature is over 900 psi). Consequently, design and construction of equipment is significantly more expensive than for analogous processes carried out at atmospheric pressure.
Second, utility costs resulting from processing with high pressure carbon dioxide can be prohibitively high. For example, while it has been suggested that depressurization of a carbon dioxide solution to one atmosphere is an easy route to recovery of products, a carbon dioxide-based process may not be economically viable if extensive depressurization is used to recover dissolved products. Indeed, the known carbon dioxide-based coffee decaffeination process is economically viable, in part, because the carbon dioxide is not depressurized to recover the caffeine following stripping of caffeine from the coffee beans. That process uses water to extract the caffeine from the carbon dioxide in a countercurrent liquid-liquid column (the caffeine is ultimately recovered via reverse osmosis).
Another significant obstacle to the use of carbon dioxide as a solvent in conventional chemical processes is its low solvent power. Although carbon dioxide's solvent power was once suggested to be comparable to that of liquid alkanes, recent research has shown that this generalization is in error. Calculated solubility parameters for carbon dioxide are approximately 4-5 cal/cm 3 in the liquid state, similar to that of fluorinated materials and slightly lower than that for silicones. It is generally accepted that carbon dioxide will not solubilize significant quantities of polar, high molecular weight, or ionic compounds. Low solubilities of compounds of interest require large volumes of carbon dioxide in a potential process, and thus the chance for favorable economics diminishes.
SYNTHESIS OF CO 2 -MISCIBLE FUNCTIONALIZED ANTHRAQUINONES (FAQ'S)
In the present invention, novel, highly CO 2 -miscible/soluble analogs of 2-alkyl anthraquinones are first synthesized. These functionalized analogs are then use in the synthesis of hydrogen peroxide in carbon dioxide via sequential reaction with hydrogen, and then oxygen as illustrated below.
2-alkyl anthraquinones typically used in the commercial synthesis of hydrogen peroxide exhibit negligible solubility in carbon dioxide at pressures up to 5000 psi at room temperature. It has been discovered that highly CO 2 -soluble/miscible analogs of anthraquinone can be synthesized via modification or functionalization of anthraquinone with CO 2 -philic groups. Such functionalized anthroquinones are often abbreviated as FAQ's herein. The CO 2 -philic groups suitable for use in the present invention include, for example, fluoroether groups, fluoroalkyl groups, silicones, fluorinated acrylates and phosphazines.
Analogs of 2-alkyl anthraquinone have been synthesized via the reaction of a commercially available anthraquinone functionalized with a first reactive group with a CO 2 -philic group functionalized with a second reactive group, wherein the first reactive group and the second reactive group are selected to react to link the CO 2 -philic group to the anthraquinone ring structure via a resultant connector or spacer group R S . The CO 2 -philic group can also be directly linked to the anthraquinone ring structure. Oligomeric (generally, with a molecular weight above 50) fluoroether CO 2 -philic groups were used as models in the present studies. For example, fluoroether acid chloride (generated from a 2500 molecular weight (MW) fluoroether carboxylic acid obtained from DuPont) was reacted with 2-amino anthraquinone (obtained from Aldrich Chemical). In that reaction, the acid chloride functional group and the amino functional group react to form an amide connector or linkage.
The functionalized fluoroether anthraquinone analogs of the present studies are much more soluble in carbon dioxide than a 2-alkyl anthraquinone. Moreover, the CO 2 -miscible/soluble analogs of anthraquinone of the present invention were found to retain their reactivity towards hydrogen.
PHASE BEHAVIOR OF FUNCTIONALIZED ANTHRAQUINONES
Mixtures of the FAQ analogs of the present invention and carbon dioxide were found to exhibit asymmetric liquid-liquid phase envelopes in P-x space. An idealized representation of such an asymmetric liquid-liquid phase envelope is illustrated in FIG. 1 . To achieve complete miscibility over a broad range of concentrations, the operating pressure is preferably chosen to be above the maximum of the cloud point curve. However, the reactions of the present invention are preferably operated at room temperature and at as low a pressure as possible to reduce operating costs. Phase behavior studies of a number of fluoroether model FAQ's of the present invention were thus undertaken to study the effect of various parameters on the miscibility of the FAQ analogs in carbon dioxide.
In that regard, the effects of three different arameters on solubility of the FAQ analogs in carbon dioxide have been studied: (1) the effect of tail length, (2) the effect of head group, (3) the effect of numbers of tails and the position of the tail on the anthraquinone aromatic rings.
FIGS. 2 and 3 depict a portion of the cloud point curves of a number of FAQ's having different tail lengths. In FIG. 2, the effect of tail length (MW=2500, 5000 and 7500) upon the miscibility in carbon dioxide of a fluoroether oligomer attached to the 2-carbon of the anthraquinone ring by an amide connector group is illustrated. In FIG. 3, the effect of tail length (MW=700, 2500, 5000 and 7500) upon the miscibility in carbon dioxide of a fluoroether oligomer attached to the 2-carbon of the anthraquinone ring by an ester connector group is illustrated. As illustrated in FIGS. 2 and 3, the pressure required to achieve miscibility generally reduces with increasing tail length. However, as illustrated in a comparison of the cloud point curves of the 5000 and 7500 MW analogs in FIG. 3, as tail length (MW) increases, the gain in solubility due to a higher contribution of the hydrophobic/CO 2 -philic group (R C ) is eventually overcome by the larger value of the entropy of mixing. At this point, the global effect of these two factors is a decrease in solubility compared to lower molecular weigh tails.
In the studies of FIG. 4, the effect of the identity of the connector or spacer group (R S ) and the position thereof upon the miscibility of the FAQ is illustrated. As illustrated, the miscibility of the FAQ with the ester spacer group is greater than those with the amide linkage. This phenomenon is believed to result from the ability of certain spacer groups to hydrogen bond, and thus resist salvation by carbon dioxide. Such hydrogen bonding does not occur in the case of the methyl ester spacer group (shown below) of FIG. 4 .
No Hydrogen Bonding
Likewise, hydrogen bonding does not occur in the case of a tertiary amide spacer groups such as an —NCH 2 CO— (shown below).
No Hydrogen Bonding
In general, replacement of the secondary amide proton with a methyl group is found to drop the cloud point curve by approximately 700 psi. Replacement of the tertiary amide spacer with an ester spacer drops the cloud point curve approximately an additional 200 psi, revealing a thermodynamic preference of carbon dioxide for the 2-methyl ester linkage over the N-substituted amide.
Furthermore, the position of spacer groups capable of forming hydrogen bonds also affects the miscibility of the FAQ. As illustrated in FIGS. 4 and 5 and in the chemical formulas below, 1-, 1, 4- and 1, 2-substitutions, which can readily form intramolecular hydrogen bonds, exhibit greater miscibility than 2-, and 2, 6-substitutions, which can only form intermolecular hydrogen bonds.
Intermolecular Hydrogen Bonding
Intramolecular Hydrogen Bonding
RATE OF REACTION/DIFFUSION COEFFICIENTS
In a heterogeneous catalytic system as occurs in the hydrogenation reaction of the present invention, the overall rate of reaction can be controlled or limited either by the inherent kinetics of the reaction or by the rate of diffusion of one or more of the reactants to the catalytic sites. The effectiveness factor, or η, is the ratio of the actual rate to that of the purely kinetic rate, such that an effectiveness factor of 1.0 indicates a purely kinetically controlled reaction, while lower values imply mass transport limitations. The effectiveness factor is a strong function of the Thiele modulus (a dimensionless number incorporating both the true kinetic rate constant and the diffusion coefficient for the reactants within the catalyst particle). As the diffusion coefficient increases, the Thiele modulus decreases and the effectiveness factor approaches 1.0.
In the present studies, effective psuedo-first order rate constants, k eff , (including contributions from both the true kinetic rate constant and the diffusion coefficient of the functionalized analog of anthraqiunone in the pores of the catalyst) were studied for the hydrogenation reaction. The calculated kinetic data and diffusion coefficients for functional groups of different lengths and spacer groups are set forth in Table 2 and in FIG. 7 . As illustrated, the diffusion coefficient was found to decrease with increasing functional group length.
EXPERIMENTAL
Materials and Methods
Oligomers of hexafluoropropylene functionalized at one end with a carboxilic group (DuPont, FW=700, 2500, 5000, 7500), thyonyl chloride (99.9%, Aldrich), N, N dimethyl formamide (Aldrich), and perfluoro-2,5,8-trimethyl-3,6,9-trioxadodecanoyl fluoride (Aldrich) were used as received. 1-aminoanthraquinone(97%, Aldrich), 1-(methylamino)anthraquinone (98%, Aldrich), 2-aminoanthraquinone (technical grade), 1,2-diaminoanthraquinone (Aldrich), 1,4-diaminoanthraquinone (Aldrich, 85%), 2,6-diaminoanthraquinone (Aldrich, 97%), 2-hydroxymethyl)-anthraquinone were used as purchased. Perfluoro 1,3-dimethylcyclohexane (Aldrich, 80%) and 1,1,2-trichlorotrifluoroethane were distilled and dried on 4A molecular sieves. Palladium, 1 wt % on alumina powder (Aldrich) was used as received. Pd catalysts with larger particle sizes were prepared by compressing the powdered catalyst into pallets which were sieved into 3 fractions: 20<d p <40 mesh, 40<d p <60 mesh, , 60<d p 21 80 mesh.
Phase behavior of FAQ's was measured in a high pressure, variable volume view cell (D. B. Robinson and Associates). A known amount of FAQ was loaded on the top of a quartz cell sealed inside a steel housing. The movement of a floating piston that separates the transmitting-pressure fluid, in this case, silicone oil, from the mixture to be analyzed, regulates the pressure inside the cell. After a known amount of CO 2 was added to the cell by one of the two Ruska syringe pumps, the pressure was raised by injection of silicone oil to a point where a single phase existed. Phase transition was determined by slowly lowering the pressure till the outset of a phase separation, indicated by a slight turbidity, was observed. Subsequently, a new amount of CO 2 was injected in the cell, and the procedure was repeated for another concentration of FAQ till the phase diagram was completed. Solubility data of different FAQ's described herein is presented in FIGS. 2 through 5.
EXAMPLE 1
This example describes the procedure used to synthesize mono amide functionalized anthraquinones illustrated below (entries 1-5 in Table 1 below).
In the abbreviation x—(Kr—CONH)—AQ, x represents the position of the functional group (that is, either on the 1 or 2 carbon of the anthrqauinone ring structure in this example), Kr represents the fluoroether group (R C ), —CONH— represents the amide connecting or spacer group (R S ) that links the fluoroether group to the anthraquinone ring structure, and AQ represents the anthraquinone ring structure.
2 mmole of fluoroether acid chloride (MW=2500, 5000, 7500) and 4 mmole of mono-amino anthraquinone were heated at 100° C. under nitrogen atmosphere. After five hours of reaction, the reaction mixture was dissolved in 50 cm 3 of perfluoro 1,3-dimethylcyclohexane, the excess of amine was removed by filtration, and the solvent was evaporated under vacuum. The product was washed several times with acetone. The chemical structure of the product was established by its NMR and IR spectrum. (entries 1-5 in Table 1).
EXAMPLE 2
This example describes the procedure used to synthesized di-amino functionalized anthraquinones illustrated below (entries 6-8 in Table 1).
In the abbreviation x, y-Twin (2500)—AQ, x and y represent the position of the functional groups on the anthrqauinone ring structure, Twin(2500) represents two fluoroether groups (R C ), each having a molecular weight of approximately 2500, and AQ represents the anthraquinone ring structure. The —CONH— amide connecting or spacer group (R S ) that links each of the fluoroether groups to the anthraquinone ring structure is not set forth in the abbreviation.
2 mmole of diaminoanthraquinone and 4 mmole fluoroether acid chloride were heated at 100 C in the presence of 4.5 mmole of pyradine under nitrogen atmosphere. After 5 hours of reaction, 50 ml of perfluoro 1,3-dimethylcyclohexane was added to the mixture, and the pyridinium chloride formed in the reaction along with the excess of pyridine was washed with a solution of 5% HCl in a separatory funnel. The solvent was evaporated under vacuum in the presence of 10 cm 3 benzene which helped the removal of water emulsified during the wash with hydrochloric acid solution. The chemical structure of the product was established by its NMR and IR spectrum (entries 6-8 in Table 1).
EXAMPLE 3
The following example describes the procedure used for synthesis of fluoroether ester anthraquinones illustrated below (entries 9-12 in Table 1).
In the abbreviation x—(Kr—COO—CH 2 )—AQ, 2 represents the position of the functional group on the 2 carbon of the anthrqauinone ring structure in this example, Kr represents the fluoroether group (R C ), —COO—CH 2 — represents the methyl ester spacer group (R S ) that links the fluoroether group to the anthraquinone ring structure, and AQ represents the anthraquinone ring structure.
3.5 moles of fluoroether acid chloride was added dropwise in a reaction mixture consisting of 0.953 g (4 mmoles) of 2-(hydroxymethyl)-anthraquinone and 0.32 ml (0.31 g, 4 mmoles) of pyridine. After the reaction mixture was mixed for 10-15 minutes at room temperature, 30 cm 3 of 1,1,2-trifluorotrichloroethane was added and the mixture was refluxed for additional 3 hours. After the completion of the reaction, pyridinium chloride (white salt) formed in the reaction was removed by filtration under vacuum. Subsequently, the excess of pyridine was washed three times with a 5% HCl solution in a separatory funnel, and the solvent along with water emulsified during the washing were removed by heating under vacuum in the presence of 5 ml of benzene. The product was identified by the appearance of the ester peak at 1780 cm −1 and the disappearance of the acid chloride peak at 1806 cm −1 in the FT-IR spectrum along with the disappearance of OH peak at 4.7 ppm in the NMR spectrum (entries 9-12 in Table 1).
The fluoroether acid chloride used in examples 1-3 was prepared as follows:
5 mmols of oligomers of hexafluoropropylene functionalized at one end with a carboxilic group (MW=2500, 5000, 7500) and 50 cm 3 of 1,3-dimethylcyclohexane along with 25 mmols of thyonyl chloride (2.97 g., 1.82 ml) and 10 mmols of N, N dimethyl formamide (0.73 g., 0.77 ml.) were added in a one neck flask equipped with a dry-ice condenser. The reaction mixture was heated at the reflux of thyonyl chloride (t=82° C.) for six hours under a blanket of nitrogen. After reaction, the two phase system was separated in a separator funnel and the solvent was removed under vacuum at 75-80 C. The product was characterized by the disappearance of the carboxilic group peak at 1775 cm −1 and the appearance of the acid chloride peak at 1805 cm −1 in the FT-IR spectrum.
EXAMPLE 4
The following example provides experimental details for a typical hydrogenation process of functionalized anthraquinone prepared as in Example 1-3.
Hydrogenation experiments in liquid CO 2 were performed using apparatus shown in FIG. 8 . The experimental setup consisted of two independent sections. An H 2 —CO 2 mixture was prepared in section A consisting of a syringe pump (High Pressure Equipment) and a sample injection valve (Rheodyne) both connected to a vacuum and venting line. H 2 —CO 2 mixture was prepared in the syringe pump for the experiments requiring a large amount of H 2 while the precise amounts of H 2 were injected in the reactor through the sample injection valve. The amount of H 2 injected in the syringe pump was calculated using a virial equation of state at the pressure indicated by the regulator mounted on the H 2 tank. The hydrogenation process was carried in section B consisting of a 35 cm 3 stainless steel reactor vessel produced at University of Pittsburgh, and equipped with a mechanical stirrer (modified Parr stirring unit). An internal filter corresponding to the output recirculating port was mounted on the lateral wall of the reactor vessel to prevent entrainment of the catalyst particles in the system.
In a regular run, the reactor was loaded with one of the FAQ's prepared as described in Example 1—3 and with Pd/Al 2 O 3 catalyst. Subsequently, both sections of the system were thoroughly vacuumed at 1-2 mm Hg for 15 minutes to remove any trace of oxygen that might react with H 2 FAQ. After the syringe pump in section A was filled with H 2 , both sections A and B were pressurized at a pressure of 900-1000 psi bellow the target or operating pressure using a combination of a Haskell gas booster and an Eldex piston pump and supercritical grade carbon dioxide (Praxair). The magnetic stirrer was started in the reactor and the mixture was stirred for 10 minutes to allow enough time for FAQ to dissolve. Meanwhile, the UV adsorption of pure CO 2 was measured to be used as reference for the UV measurements of FAQ. After equilibration, the high pressure gear pump (Micropump) was turned on and valve T4 (left) was open to start the circulation of fluid through the UV spectrometer. After stabilization of the UV spectrometer, the initial spectrum of FAQ was recorded in a range between 290-370 nm. Subsequently, the CO 2 —H 2 mixture was injected, and the hydrogenation reaction at room temperature was followed in time by the disappearance of the peak at 320 nm (functionalized esters) or 330 nm (functionalized amides) (FIG. 6 ). After the reaction was completed, the high pressure reactor was slowly depressurized, and then H 2 FAQ was exposed to air to produce H 2 O 2 and regenerate the initial FAQ. Residual FAQ in the vessel was washed with 1,1,2-tricholorotrifluoroethane and the solution was analyzed by IR and NMR.
EXAMPLE 5
Following the procedure of example 4, a functionalized anthraquinone (2-AQ—NHCO-2500) made as per example 1 was used to produce H 2 O 2 . The hydrogenation vessel was charged with 0.055 g FAQ (0.02 mmole; 0.57 mM) and different amounts of 1% Pd/Al 2 O 3 catalyst, 20-40 mesh. Molar ratio H 2 :FAQ was 10:1, the operating pressure and temperature were 3450 Psi and 25° C. respectively. The catalyst loading was varied in the range of 2.57-4.28 g/l. Assuming first order reaction with respect to FAQ, the effective rate constant in the hydrogenation process was 0.49 cm 3 /(g s).
EXAMPLE 6
1% Pd/Al 2 O 3 catalyst, 40-60 mesh was used in the hydrogenation process as in example 5. Catalyst loading was varied in the range of 2.0-3.42 g/l. Assuming first order reaction with respect to FAQ, the effective rate constant in the hydrogenation process was 0.75 cm 3 /(g s).
EXAMPLE 7
1% Pd/Al 2 O 3 catalyst, 60-80 mesh was used in the hydrogenation process as in example 5. Catalyst loading was varied in the range of 1.14-1.71 g/l. Assuming first order reaction with respect to FAQ, the effective rate constant in the hydrogenation process was 1.51 cm 3 /(g s).
EXAMPLE 8
1% Pd/Al 2 O 3 powdered catalyst (Aldrich) was used in the hydrogenation process as in example 5. Catalyst loading was varied in the range of 1.14-1.71 g/l. Assuming first order reaction with respect to FAQ, the effective rate constant in the hydrogenation process was 1.81 cm 3 /(g s).
EXAMPLE 9
Following the procedure of Example 4, a functionalized anthraquinone (2-AQ—NHCO-5000) made as per Example 1 was used to produce H 2 O 2 . The hydrogenation vessel was charged with 0.105 g FAQ (0.02 mmole; 0.57 mM) and different amounts of 1% Pd/Al 2 O 3 catalyst, 20-40 mesh. Molar ratio of H 2 :FAQ was 10:1, and the operating pressure and temperature were 3450 Psi and 25° C., respectively. Catalyst loading was varied in the range of 3.71-7.14 g/l. Assuming first order reaction with respect to FAQ, the effective rate constant in the hydrogenation process was 0.30 cm 3 /(g s)
EXAMPLE 10
1% Pd/Al 2 O 3 catalyst, 40-60 mesh was used in the hydrogenation process as in example 9. Catalyst loading was varied in the range of 2.57-4.57 g/l. Assuming first order reaction with respect to FAQ, the effective rate constant was 0.45 cm 3 /(g s).
EXAMPLE 11
1% Pd/Al 2 O 3 catalyst, 60-80 mesh was used in the hydrogenation process as in example 9. Catalyst loading was varied in the range of 1.56-2.52 g/l. Assuming first order reaction with respect to FAQ, the effective rate constant in the hydrogenation process was 0.85 cm 3 /(g s).
EXAMPLE 12
1% Pd/Al 2 O 3 powdered catalyst was used in the hydrogenation process as in example 9. Catalyst loading was varied in the range of 1.14-2.18 g/l. Assuming first order reaction with respect to FAQ, the effective rate constant in the hydrogenation process was 1.83 cm 3 /(g s).
EXAMPLE 13
Following the procedure of Example 4, a functionalized anthraquinone (2-AQ—NHCO-7500) made as per Example 1 was used to produce H 2 O 2 . The hydrogenation vessel was charged with 0.155 g FAQ (0.02 mmole; 0.57 mM) and different amounts of 1% Pd/Al 2 O 3 catalyst, 20-40 mesh. Molar ratio of H 2 :FAQ was 10:1, and the operating pressure and temperature were 3450 Psi and 25° C., respectively. Catalyst loading was varied in the range of 2.52-5.86 g/l. Assuming first order reaction with respect to FAQ, the effective rate constant in the hydrogenation process was 0.22 cm 3 /(g s).
EXAMPLE 14
1% Pd/Al 2 O 3 catalyst, 40-60 mesh was used in the hydrogenation process as in example 13. Catalyst loading was varied in the range of 1.9-3.85 g/l. Assuming first order reaction with respect to FAQ, the effective rate constant was 0.32 cm 3 /(g s).
EXAMPLE 15
1% Pd/Al 2 O 3 catalyst, 60-80 mesh was used in the hydrogenation process as in example 13. Catalyst loading was varied in the range of 1.54-2.85 g/l. Assuming first order reaction with respect to FAQ, the effective rate constant in the hydrogenation process was 0.72 cm 3 /(g s).
EXAMPLE 16
1% Pd/Al 2 O 3 powdered catalyst was used in the hydrogenation process as in example 13. Catalyst loading was varied in the range of 1.54-2.85 g/l. Assuming first order reaction with respect to FAQ, the effective rate constant in the hydrogenation process was 1.11 cm 3 /(g 5).
EXAMPLE 17
Following the procedure of Example 4, a functionalized anthraquinone (2-AQ—CH 2 OCO-2500) made as per Example 3 was used to produce H 2 O 2 . The hydrogenation vessel was charged with 0.055 g FAQ (0.02 mmole; 0.57 mM) and different amounts of 1% Pd/Al 2 O 3 catalyst, 20-40 mesh. Molar ratio of H 2 :FAQ was 10:1, and the operating pressure and temperature were 3450 Psi and 25° C., respectively. Catalyst loading was varied in the range of 2.0-3.85 g/l. Assuming first order reaction with respect to FAQ, the effective rate constant in the hydrogenation process was 0.814 cm 3 /(g s).
EXAMPLE 18
1% Pd/Al 2 O 3 catalyst, 40-60 mesh was used in the hydrogenation process as in example 17. Catalyst loading was varied in the range of 1.25-1.99 g/l. Assuming first order reaction with respect to FAQ, the effective rate constant in the hydrogenation process was 1.72 cm 3 /(g s).
EXAMPLE 19
1% Pd/Al 2 O 3 catalyst, 60-80 mesh was used in the hydrogenation process as in example 17. Catalyst loading was varied in the range of 1.06-1.38 g/l. Assuming first order reaction with respect to FAQ, the effective rate constant in the hydrogenation process was 3.38 cm 3 /(g s).
EXAMPLE 20
1% Pd/Al 2 O 3 powdered catalyst was used in the hydrogenation process as in example 17. Catalyst loading was varied in the range of 0.47-0.9 g/ 1. Assuming first order reaction with respect to FAQ, the effective rate constant in the hydrogenation process was 3.58 cm 3 /(g s).
EXAMPLE 21
Following the procedure of Example 4, a functionalized anthraquinone (2-AQ—CH 2 0CO-5000) made as per Example 3 was used to produce H 2 O 2 . The hydrogenation vessel was charged with 0.105 g FAQ (0.02 mmole; 0.57 mM) and different amounts of 1% Pd/Al 2 O 3 catalyst, 20-40 mesh. Molar ratio of H 2 :FAQ was 10:1, and the operating pressure and temperature were 3450 Psi and 25° C. respectively. Catalyst loading was varied in the range of 2.1-3.44 g/l. Assuming first order reaction with respect to FAQ, the effective rate constant in the hydrogenation process was 0.397 cm 3 /(g s).
EXAMPLE 22
1% Pd/Al 2 O 3 catalyst, 40-60 mesh was used in the hydrogenation process as in example 21. Catalyst loading was varied in the range of 1.66-3.17 g/l. Assuming first order reaction with respect to FAQ, the effective rate constant in the hydrogenation process was 1.02 cm 3 /(g s).
EXAMPLE 23
1% Pd/Al 2 O 3 catalyst, 60-80 mesh was used in the hydrogenation process as in example 21. Catalyst loading was varied in the range of 1.18-1.74 g/l. Assuming first order reaction with respect to FAQ, the effective rate constant in the hydrogenation process was 1.41 cm 3 /(g s).
EXAMPLE 24
1% Pd/Al 2 O 3 powdered catalyst, was used in the hydrogenation process as in example 21. Catalyst loading was varied in the range of 1.02-1.85 g/l. Assuming first order reaction with respect to FAQ, the effective rate constant in the hydrogenation process was 2.02 cm 3 /(g s).
TABLE 1
Structural Characterization of Functionalized AQ
Kr COCl
Entry
AQ
(MW)
Product
IR
NMR
1
2-NH 2 -AQ
2500
2-(2500-NHCO)-AQ
1539, 1589, 1680
7.25, 8.09,
1737, 3321
10.15
2
2-NH 2 -AQ
5000
2-(5000-CONH)-AQ
1538, 1589, 1675
7.29, 8.08,
1738, 3325
10.21
3
2-NH 2 -AQ
7500
2-(7500-CONH)-AQ
1540, 1593, 1675
7.32, 8.15,
1738, 3321
10.05
4
1-NH 2 -AQ
5000
1-(5000-CONH)-AQ
1419, 1523, 1587,
8.15-8.30,
1677, 1744, 3105
9.09
5
1-N(Me)-AQ
5000
1-(5000-CON(Me))-AQ
1425, 1592, 1675,
2.09, 7.28
1740, 3040, 3068
8.26, 8.44
6
1,2-NH 2 -AQ
2500
1,2-Twin(2500)-AQ
1532, 1599, 1677,
8.11, 9.16,
1724, 1739
10.00
7
1,4-NH 2 -AQ
2500
1,4-Twin(2500)-AQ
1518, 1597, 1653,
7.23, 8.32,
1749
9.16
8
2,6-NH 2 -AQ
2500
2,6-Twin(2500)-AQ
1583, 1594, 1678,
8-8.30,
1722, 3320
10.33
1440, 1592, 1674,
2.08, 5.45,
9
2-(CH 2 OH)-AQ
700 a
2-(700-COO-CH 2 )-AQ
1778, 3045, 3065,
8.24
3321
1441, 1593, 1674,
2.11, 5.46,
10
2-(CH 2 OH)-AQ
2500
2-(2500-COO-CH 2 )-AQ
1779, 3046, 3065,
8.23
3322
1443, 1593, 1675
2.09, 5.45,
11
2-CH 2 OH)-AQ
5000
2-(5000-COO-CH 2 )-AQ
1780, 3046, 3066,
8.25
3323
1441, 1593, 1675
2.04 5.43
12
2-(CH 2 OH)-AQ
7500
2-(7500-COO-CH 2 )-AQ
1779, 3046, 3066
8.29
3323
(1) Prepared as in Example 3 from perfluoro-2,5,8-trimethyl-3,6,9-trioxadodecanoyl fluoride and 2-(hydroxymethyl)-anthraquinone.
TABLE 2
Mass transfer and kinetic parameters
k c (1)
De (1)
cm 3 /(g s)
cm 2 /s 10 5
η (2)
MM
Amide
Ester
Amide
Ester
Amide
Ester
2500
2.12
3.83
9.91
12.5
0.85
0.92
5000
2.12
3.83
4.6
4.25
0.85
0.903
7500
2.12
1.81
0.4
2-EtAQ
0.47 (3)
(1) Value determined from the regression s vs d p ; where s is the slope of the linear dependence 1/k eff vs 1/w (d p —particle size; w—catalyst loading);
(2) h = k c /k powd (k powd —effective rate constant determined experimentally for the powdered catalyst)
(3) Value obtained by extrapolation of the data from Santacesaria, E.; Di Serio, M.; Velotti, R.; Leone, U. Ind. Eng. Chem. Res., 1994, 33, 277.
Although the present invention has been described in detail in connection with the above examples, it is to be understood that such detail is solely for that purpose and that variations can be made by those skilled in the art without departing from the spirit of the invention except as it may be limited by the following claims. | A method for synthesizing hydrogen peroxide comprises the steps of: synthesizing an analog of anthraquinone that is miscible or soluble in carbon dioxide; reacting the analog of anthraquinone with hydrogen in carbon dioxide to produce a corresponding analog of tetrahydroquinone; and reacting the analog of tetrahydroquinone with oxygen to produce the hydrogen peroxide and regenerate the analog of anthraquinone. A chemical compound having the formula:
wherein R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , and R 8 are independently, the same or different, H, R C , or R S R C , wherein R S is a spacer group and R C is a fluoroalkyl group, a fluoroether group, a silicone group, an alkylene oxide group, a fluorinated acrylate group, or a phosphazine group, and wherein at least one of R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , and R 8 is not H. | 2 |
FIELD OF THE INVENTION
The present invention relates generally to electronic fuses (efuses) and more particularly to diffusion barrier layers serving as efuses.
BACKGROUND OF THE INVENTION
In a conventional semiconductor integrated circuit (chip), there are efuses that can be programmed so as to determine the mode of operation of the chip. Therefore, there is a need for an efuse structure (and a method for forming the same) that is better than the efuses of the prior art.
SUMMARY OF THE INVENTION
The present invention provides an electrical fuse fabrication method, comprising forming a first electrode in a substrate; forming a dielectric layer on top of said first electrode; forming an opening in said dielectric layer such that said first electrode is exposed to a surrounding ambient through said opening; forming a fuse element on side walls and bottom walls of said opening such that said first electrode and said fuse element are electrically coupled together; and filling said opening with a dielectric material.
The present invention provides an efuse structure that is better than the efuses of the prior art.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1A-1M show cross-section views used to illustrate a fabrication process for forming a semiconductor structure, in accordance with embodiments of the present invention.
FIGS. 2A-2C show cross-section views used to illustrate a fabrication process for forming another semiconductor structure, in accordance with embodiments of the present invention.
FIGS. 3A-3H show cross-section views used to illustrate a fabrication process for forming an alternative semiconductor structure, in accordance with embodiments of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
FIGS. 1A-1M show cross-section views used to illustrate a fabrication process for forming a semiconductor structure 100 , in accordance with embodiments of the present invention. More specifically, with reference to FIG. 1A , the fabrication process for forming the semiconductor structure 100 starts with a dielectric layer 110 on top of a front-end-of-line layer (not shown). The front-end-of-line (FEOL) layer contains semiconductor devices such as transistors, resistors, capacitors, etc. (not shown). The dielectric layer 110 comprises a dielectric material such as SiCOH or SiLK on top of the FEOL layer. The dielectric layer 110 can be referred to as an inter-level dielectric layer 110 of a back-end-of-line layer (not shown). Both the dielectric layer 110 and the front-end-of-line layer can comprise oxide, diamond, glass, ceramic, quartz, or polymer.
Next, with reference to FIG. 1B , in one embodiment, trenches 111 a and 111 b are formed in the dielectric layer 110 . The trenches 111 a and 111 b can be formed by lithographic and etching processes. The trench 111 a is later used for forming a M1 metal line (not shown), whereas the trench 111 b is later used for forming a first electrode of an efuse structure (not shown).
Next, with reference to FIG. 1C , in one embodiment, a diffusion barrier layer 112 is formed on top of the dielectric layer 110 (including on the bottom walls and the side walls of the trenches 111 a and 111 b ). The diffusion barrier layer 112 comprises a diffusion barrier material such as Ta, Ti, Ru, RuTa, TaN, TiN, RuN, RuTaN, a noble metal, or a nitride material of the noble metal. The diffusion barrier layer 112 can be formed by CVD (Chemical Vapor Deposition), PVD (Physical Vapor Deposition), or ALD (Atomic Layer Deposition).
Next, in one embodiment, an electrically conductive layer 114 is formed on top of the diffusion barrier layer 112 resulting in the trenches 111 a and 111 b being filled. The electrically conductive layer 114 comprises an electrically conductive material such as Cu or Al. The electrically conductive layer 114 can be formed by an electroplating process.
Next, in one embodiment, portions of the electrically conductive layer 114 outside the trenches 111 a and 111 b are removed. More specifically, these portions of the electrically conductive layer 114 can be removed by a CMP (Chemical Mechanical Polishing) process performed on the top surface 114 ′ of the electrically conductive layer 114 until the top surface 110 ′ the dielectric layer 110 is exposed to the surrounding ambient resulting in the semiconductor structure 100 of FIG. 1 C′. The portions of the diffusion barrier layer 112 in the trenches 111 a and 111 b can be referred to as diffusion barrier regions 112 a and 112 b , respectively, as shown in FIG. 1 C′. Similarly, the portions of the electrically conductive layer 114 in the trenches 111 a and 111 b can be referred to as a M1 metal line 114 a and a first electrode 114 b of the efuse structure, respectively, as shown in FIG. 1 C′.
Next, with reference to FIG. 1D , in one embodiment, an electrically insulating cap layer 120 is formed on top of the semiconductor structure 100 of FIG. 1 C′. The electrically insulating cap layer 120 can be formed by CVD of a dielectric material such as Si 3 N 4 , SiC, SiC(N,H) or SiO 2 on top of the semiconductor structure 100 of FIG. 1 C′.
Next, in one embodiment, a dielectric layer 130 is formed on top of the electrically insulating cap layer 120 . The dielectric layer 130 comprises a dielectric material such as SiCOH or SiLK. The thickness of the dielectric layer 130 is in the range from 500 angstroms to 10,000 angstroms. The dielectric layer 130 can be formed by CVD or spin-on process.
Next, with reference to FIG. 1E , in one embodiment, via holes 131 a and 131 b and trenches 133 a and 133 b are formed in the dielectric layer 130 and the electrically insulating cap layer 120 . More specifically, the via holes 131 a and 131 b and trenches 133 a and 133 b can be formed by a conventional dual damascene process. The via hole 131 a and the trench 133 a are later used for forming a via and a M2 metal line (not shown), respectively, whereas the via hole 131 b and the trench 133 b are later used for forming an efuse (not shown) of the efuse structure.
Next, with reference to FIG. 1F , in one embodiment, a diffusion barrier layer 132 is formed on exposed surfaces of the semiconductor structure 100 of FIG. 1E . The diffusion barrier layer 132 can be formed by CVD, PVD, or ALD of a diffusion barrier material such as Ta, Ti, Ru, RuTa, TaN, TiN, RuN, or RuTaN on exposed surfaces of the semiconductor structure 100 of FIG. 1E .
Next, with reference to FIG. 1G , in one embodiment, electrically conductive regions 134 a and 134 b are formed in the via holes 131 a and 131 b and the trenches 133 a and 133 b . More specifically, the electrically conductive regions 134 a and 134 b can be formed by (i) depositing an electrically conductive material such as Cu or Al on top of the semiconductor structure 100 of FIG. 1F including inside the via holes 131 a and 131 b and the trenches 133 a and 133 b and then (ii) removing the excessive electrically conductive material and portions of the diffusion barrier layer 132 outside the via holes 131 a and 131 b and the trenches 133 a and 133 b resulting in the semiconductor structure 100 of FIG. 1G . The step (i) can be an electroplating process, whereas the step (ii) can be a CMP process.
With reference to FIG. 1G , it should be noted that the diffusion barrier regions 132 a and 132 b are what remain of the diffusion barrier layer 132 ( FIG. 1F ). The diffusion barrier regions 132 b will serve as an efuse 132 b (also called the fuse element 132 b ) of the subsequently formed efuse structure.
Next, with reference to FIG. 1H , in one embodiment, an electrically insulating cap region 140 is formed on top of the electrically conductive region 134 a and the diffusion barrier region 132 a of the semiconductor structure 100 of FIG. 1G such that the electrically conductive region 134 b remains exposed to the surrounding ambient. The electrically insulating cap region 140 can be formed by CVD of a dielectric material such as Si 3 N 4 , SiC, SiC(N,H) or SiO 2 on top of the semiconductor structure 100 of FIG. 1G followed by lithographic and etching processes.
Next, in one embodiment, the electrically conductive region 134 b is removed resulting in the semiconductor structure 100 of FIG. 1I . More specifically, the electrically conductive region 134 b can be removed by using wet etching.
Next, with reference to FIG. 1J , in one embodiment, a dielectric layer 150 is formed on top of the semiconductor structure 100 of FIG. 1I . The dielectric layer 150 comprises a dielectric material such as SiCOH or SiLK. The dielectric layer 150 can be formed by (i) spin-on or (ii) CVD followed by a CMP process.
Next, with reference to FIG. 1K , in one embodiment, via holes 151 a and 151 b are formed in the dielectric layer 150 . The via holes 151 a and 151 b can be formed by lithographic and etching processes. Next, the via hole 151 a is extended down through the electrically insulating cap region 140 by using RIE (Reactive Ion Etching) resulting in a via hole 151 a ′ of FIG. 1L .
Next, with reference to FIG. 1M , in one embodiment, diffusion barrier regions 152 a and 152 b are formed on the side walls and bottom walls of the via holes 151 a ′ and 151 b . The diffusion barrier regions 152 a and 152 b comprise a diffusion barrier material such as Ta, Ti, Ru, RuTa, TaN, TiN, RuN, RuTaN, a noble metal, or a nitride material of the noble metal. The formation of the diffusion barrier regions 152 a and 152 b is similar to the formation of the diffusion barrier region 112 a and 112 b.
Next, in one embodiment, electrically conductive regions 154 a and 154 b are formed in the via holes 151 a ′ and 151 b , respectively. The electrically conductive regions 154 a and 154 b comprise an electrically conductive material such as Cu or Al. The formation of the electrically conductive regions 154 a and 154 b is similar to the formation of the electrically conductive regions 114 a and 114 b described earlier. The electrically conductive region 154 b will serve as a second electrode 154 b of the efuse structure. It should be noted that the first electrode 114 b , the efuse 132 b , and the second electrode 154 b constitute an efuse structure 114 b + 132 b + 154 b.
In one embodiment, the efuse structure 114 b + 132 b + 154 b can be programmed by blowing off the efuse 132 b such that the first electrode 114 b and the second electrode 154 b are electrically disconnected from each other. More specifically, the efuse 132 b can be blown off by sending a sufficiently large current through the efuse 132 b.
FIGS. 2A-2C show cross-section views used to illustrate a fabrication process for forming a semiconductor structure 200 , in accordance with embodiments of the present invention. More specifically, the fabrication process for forming the semiconductor structure 200 starts with the semiconductor structure 200 of FIG. 2A , wherein the semiconductor structure 200 of FIG. 2A is similar to the semiconductor structure 100 of FIG. 1H . The formation of the semiconductor structure 200 of FIG. 2A is similar to the formation of the semiconductor structure 100 of FIG. 1H .
Next, in one embodiment, a top portion 134 b ′ of the electrically conductive region 134 b is removed resulting in an electrically conductive region 234 b being left in the via hole 131 b as shown in FIG. 2 A′. The electrically conductive region 134 b can be removed by wet etching. In one embodiment, the removal of the top portion 134 b ′ is controlled such that a resistance of the resulting combination of the diffusion barrier regions 132 b and the electrically conductive region 234 b is equal to a pre-specified value.
Next, with reference to FIG. 2B , in one embodiment, a dielectric layer 250 is formed on top of the semiconductor structure 200 of FIG. 2 A′. The dielectric layer 250 comprises a dielectric material such as SiCOH or SiLK. The dielectric layer 250 can be formed by (i) spin-on or (ii) CVD followed by a CMP process.
Next, with reference to FIG. 2C , in one embodiment, diffusion barrier regions 252 a and 252 b and electrically conductive regions 254 a and 254 b are formed in the dielectric layer 250 in a manner which is similar to the manner in which the diffusion barrier regions 152 a and 152 b and the electrically conductive regions 154 a and 154 b are formed in FIG. 1M . The electrically conductive region 254 b will serve as a second electrode 254 b of an efuse structure of the semiconductor structure 200 of FIG. 2C . It should be noted that the first electrode 114 b , the efuse 132 b , the electrically conductive region 234 b , and the second electrode 254 b are parts of an efuse structure 114 b + 132 b + 234 b + 254 b.
In one embodiment, the efuse structure 114 b + 132 b + 234 b + 254 b can be programmed in a manner which is similar to the manner in which the efuse structure 114 b + 132 b + 154 b of semiconductor structure 100 of FIG. 1M is programmed. It should be noted that the efuse structure 114 b + 132 b + 234 b + 254 b can be used as a resistor.
FIGS. 3A-3H show cross-section views used to illustrate a fabrication process for forming a semiconductor structure 300 , in accordance with embodiments of the present invention. More specifically, the fabrication process for forming the semiconductor structure 300 starts with the semiconductor structure 300 of FIG. 3A , wherein the semiconductor structure 300 of FIG. 3A is similar to the semiconductor structure 100 of FIG. 1F . The formation of the semiconductor structure 300 of FIG. 3A is similar to the formation of the semiconductor structure 300 of FIG. 1F .
Next, with reference to FIG. 3 A′, in one embodiment, a dielectric layer 334 is formed on top of the diffusion barrier layer 132 resulting in the via holes 131 a and 131 b and the trenches 133 a and 133 b being filled. The dielectric layer 334 comprises a dielectric material such as SiLK or SiCOH. The dielectric layer 334 can be formed by CVD or spin-on process.
Next, with reference to FIG. 3B , in one embodiment, an electrically insulating cap region 340 is formed on top of the dielectric layer 334 such that (i) the electrically insulating cap region 340 does not overlap the via hole 131 a and the trench 133 a and (ii) the via hole 131 b and the trench 133 b are directly beneath the electrically insulating cap region 340 . The electrically insulating cap region 340 can be formed by CVD or spin-on process of a dielectric material such as Si 3 N 4 , SiC, SiC(N,H) or SiO 2 on top of the semiconductor structure 300 of FIG. 3 A′ followed by lithographic and etching processes.
Next, in one embodiment, the electrically insulating cap region 340 is used as a blocking mask to etch down the dielectric layer 334 until portions of the dielectric layer 334 inside the via hole 131 a and the trench 133 a are completely removed resulting in the semiconductor structure 300 of FIG. 3C . The step of etching down the dielectric layer 334 can be performed by using RIE.
Next, with reference to FIG. 3D , in one embodiment, a diffusion barrier layer 350 is formed on exposed surfaces of the semiconductor structure 300 of FIG. 3C . The diffusion barrier layer 350 can be formed by CVD, PVD, or ALD of a diffusion barrier material such as TaN or TiN on exposed surfaces of the semiconductor structure 300 of FIG. 3C .
Next, with reference to FIG. 3E , in one embodiment, an electrically conductive layer 360 is formed on top of the semiconductor structure 300 of FIG. 3D resulting in the via hole 131 a and the trench 133 a are filled. The electrically conductive layer 360 comprises an electrically conductive material such as Cu or Al. The electrically conductive layer 360 can be formed by an electroplating process.
Next, in one embodiment, (i) portions of the electrically conductive layer 360 and the diffusion barrier layer 350 outside the via hole 131 a and trench 133 a , (ii) portions of the dielectric layer 334 outside the via hole 131 b and the trench 133 b , and (iii) the electrically insulating cap region 340 are removed resulting in the semiconductor structure 300 of FIG. 3F . These removals can be performed by a CMP process.
Next, with reference to FIG. 3G , in one embodiment, an electrically insulating cap layer 370 is formed on top of the semiconductor structure 300 of FIG. 3F . The electrically insulating cap layer 370 comprises a dielectric material such as Si 3 N 4 , SiC, SiC(N,H) or SiO 2 . The electrically insulating cap layer 370 can be formed by CVD or spin-on process.
Next, in one embodiment, a dielectric layer 380 is formed on top of the electrically insulating cap layer 370 . The dielectric layer 380 comprises a dielectric material such as SiCOH or SiLK. The dielectric layer 380 can be formed by CVD or spin-on process.
Next, with reference to FIG. 3H , in one embodiment, diffusion barrier regions 382 a and 382 b and the electrically conductive regions 384 a and 384 b are formed in the dielectric layer 380 in a manner which is similar to the manner in which the diffusion barrier regions 152 a and 152 b and electrically conductive regions 154 a and 154 b are formed in FIG. 1M . The electrically conductive region 384 b will serve as a second electrode 384 b of an efuse structure of the semiconductor structure 300 of FIG. 3H . It should be noted that the first electrode 114 b , the efuse 132 b , and the second electrode 384 b constitute an efuse structure 114 b + 132 b + 384 b.
In one embodiment, the structure of the semiconductor structure 300 of FIG. 3H is similar to the structure of the semiconductor structure 100 of FIG. 1M except that the semiconductor structure 300 comprises the diffusion barrier region 350 a . The diffusion barrier regions 132 a and 350 a can be collectively referred to as a diffusion barrier region 132 a + 350 a . The thickness of the diffusion barrier region 132 a + 350 a can be customized to a desired thickness by adjusting the thickness of the diffusion barrier region 350 a . As a result, in comparison with the diffusion barrier region 132 b of FIG. 1M , the diffusion barrier region 132 a + 350 a of FIG. 3H improves the prevention of diffusion of the electrically conductive material of the electrically conductive region 360 a through the diffusion barrier region 132 a + 350 a . In one embodiment, the efuse structure 114 b + 132 b + 384 b can be programmed in a manner which is similar to the manner in which the efuse structure 114 b + 132 b + 154 b of semiconductor structure 100 of FIG. 1M is programmed.
In summary, with reference to FIG. 1M , the diffusion barrier regions 132 a and 132 b (i) are similar and (ii) can be formed simultaneously, wherein the diffusion barrier region 132 b can be used as an efuse of the efuse structure 114 b + 132 b + 154 b . In FIG. 2C , the electrically conductive region 234 b is left in the via hole 131 b so as to decrease the resistance of the efuse. As a result, the resistance of the efuse can be tuned to a desired value. Therefore, the efuse structure 114 b + 132 b + 234 b + 254 b can also be used as a resistor having a desired resistance. In FIG. 3H , the electrically conductive region 360 a is surrounded by the diffusion barrier region 132 a + 350 a whose thickness can be at any desirable value.
In the embodiments described above, the dielectric layer 110 is the first inter-level dielectric layer. In an alternative embodiment, the dielectric layer 110 can be second, third, or any inter-level dielectric layer of the back-end-of-line layer.
While particular embodiments of the present invention have been described herein for purposes of illustration, many modifications and changes will become apparent to those skilled in the art. Accordingly, the appended claims are intended to encompass all such modifications and changes as fall within the true spirit and scope of this invention. | A structure fabrication method. The method includes providing a structure. The structure includes (a) a substrate layer, (b) a first fuse electrode in the substrate layer, and (c) a fuse dielectric layer on the substrate layer and the first fuse electrode. The method further includes (i) forming an opening in the fuse dielectric layer such that the first fuse electrode is exposed to a surrounding ambient through the opening, (ii) forming a fuse region on side walls and bottom walls of the opening such that the fuse region is electrically coupled to the first fuse electrode, and (iii) after said forming the fuse region, filling the opening with a dielectric material. | 7 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] The present application is a divisional application of U.S. patent application Ser. No. 13/686,756, filed on Nov. 27, 2012, now U.S. Pat. No. 8,657,525, which is a divisional application of U.S. patent application Ser. No. 12/347,467, filed on Dec. 31, 2008, now U.S. Pat. No. 8,322,945. The present application claims the benefits of U.S. Provisional Application Ser. No. 61/061,567, filed Jun. 13, 2008, entitled “MOBILE BARRIER”, and 61/091,246, filed Aug. 22, 2008, entitled “MOBILE BARRIER”, and 61/122,941, filed Dec. 16, 2008, entitled “MOBILE BARRIER” each of which is incorporated herein by this reference in its entirety.
FIELD OF THE INVENTION
[0002] The present invention relates generally to the field of trailers and other types of barriers used to shield road construction workers from traffic. More specifically, the present invention discloses a safety and construction trailer having a fixed safety wall and semi tractor hookups at both ends.
BACKGROUND
[0003] Various types of barriers have long been used to protect road construction workers from passing vehicles. For example, cones, barrels and flashing lights have been widely used to warn drivers of construction zones, but provide only limited protection to road construction workers in the event a driver fails to take heed. Some construction projects routinely park a truck or other heavy construction equipment in the lane between the construction zone and on-coming traffic. This reduces the risk of worker injury from traffic in that lane, but does little with regard to errant traffic drifting laterally across lanes into the construction zone. In addition, conventional barriers require significant time and effort to transport to the work site, and expose workers to significant risk of accident while deploying the barrier at the work site. Therefore, a need exists for a safety barrier that can be readily transported to, and deployed at the work site. In addition, the safety barrier should protect against lateral incursions by traffic from adjacent lanes, as well as traffic in the same lane.
SUMMARY
[0004] These and other needs are addressed by the various embodiments and configurations of the present invention. In contrast to the prior art in the field, the present invention can provide a safety trailer with a fixed safety wall and semi tractor hookups at one or both ends.
[0005] In a first embodiment, a safety trailer includes:
[0006] (a) first and second removably interconnected platforms, at least one of the first and second platforms being engaged with an axle and wheels, the first and second platforms defining a trailer; and
[0007] (b) a plurality of wall sections supported by the trailer, the wall sections, when deployed to form a barrier wall, are positioned between the first and second interconnected platforms
[0008] (c) wherein at least one of the following is true:
[0009] (c1) the trailer supports a ballast member, the ballast member being positioned near a first side of the trailer and the ballast member near a second, opposing side of the trailer, the ballast member offsetting, at least partially, a weight of the plurality of wall sections, and
[0010] (c2) the axle of the trailer is engaged with a vertical adjustment member, the vertical adjustment member selectively adjusting a vertical position of a surface of the trailer.
[0011] In a second embodiment, a safety trailer includes:
[0012] (a) first and second platforms;
[0013] (b) a plurality of interconnected wall sections positioned between and connected to the first and second platforms, the plurality of wall sections defining a protected work area on a side of the trailer;
[0014] (c) wherein each wall section has at least one of the following features:
[0015] (c1) a plurality of interconnected levels, each level comprising first and second longitudinal members, a plurality of truss members interconnecting the first and second longitudinal members, and being connected to an end member;
[0016] (c2) a longitudinal member extending a length of the wall section, the longitudinal member being positioned at the approximate position of a bumper of a vehicle colliding with the wall section;
[0017] (c3) a plurality of full height and partial height wall members, the full height wall members extending substantially the height and width of the wall section and the partial height wall members extending substantially the width but less than the height of the wall section, the full height and partial height members alternating along a length of the wall section; and
[0018] (c4) first and second end members, each of the first and second end members comprising an outwardly projecting alignment member and an alignment-receiving member, the first and second end members having the alignment and alignment-receiving members positioned in opposing configurations.
[0019] In a third embodiment, a trailer includes:
[0020] (a) a trailer body;
[0021] (b) a removable caboose engageable with the trailer body, the caboose having a nose portion and at least one axle and wheels; and
[0022] (c) a caboose receiving member, the caboose receiving member comprising an alignment device, wherein, in a first mode when the caboose is moved into engagement with the trailer body, the alignment device orients the caboose with a king pin mounted on the trailer body and, in a second mode when the caboose is engaged with the trailer body, the alignment device maintains a desired orientation of the caboose with the trailer.
[0023] In a fourth embodiment, a safety system includes:
[0024] (a) a vehicle;
[0025] (b) first and second platforms;
[0026] (c) a barrier engaged with the first and second platforms, the barrier and first and second platforms forming a protected work space; and
[0027] (d) a caboose, wherein the vehicle and caboose are engaged with the first and second platforms, respectively, wherein the vehicle has a movable king pin plate engaged with a first king pin on the first platform, and wherein the caboose has a fixed king pin plate engaged with a second king pin on the second platform.
[0028] In a fifth embodiment, a safety system includes:
[0029] (a) a vehicle;
[0030] (b) first and second platforms;
[0031] (c) a barrier engaged with the first and second platforms, the barrier and first and second platforms forming a protected work space; and
[0032] (d) a caboose, wherein the vehicle and caboose are engaged with the first and second platforms, respectively, wherein the vehicle and caboose have braking systems that operate independently.
[0033] In a sixth embodiment, a trailer includes:
[0034] (a) first and second platforms;
[0035] (b) a barrier engaged with the first and second platforms, the barrier and first and second platforms forming a protected work space, wherein the barrier is formed by a plurality of interconnected wall sections and wherein the interconnected wall sections slidably engage one another.
[0036] In a seventh embodiment, a trailer includes:
[0037] (a) first and second platforms;
[0038] (b) a barrier engaged with the first and second platforms, the barrier and first and second platforms forming a protected work space, wherein the barrier is formed by a plurality of interconnected wall sections and wherein the interconnected wall sections telescopically engage one another.
[0039] In an eighth embodiment, a trailer includes:
[0040] (a) first and second platforms;
[0041] (b) a barrier engaged with the first and second platforms, the barrier and first and second platforms forming a protected area, wherein the barrier is formed by a plurality of interconnected wall sections, and wherein at least one of the following is true:
[0042] (b1) a bottom of the barrier is positioned at a distance above a surface upon which the trailer is parked and wherein the distance ranges from about 10 to about 14 inches;
[0043] (b2) a height of the barrier above the surface is at least about 3.5 feet; and
[0044] (b3) a height of the barrier from a bottom of the barrier to the top of the barrier is at least about 2.5 feet.
[0045] The present invention can provide a number of advantages depending on the particular configuration.
[0046] In one aspect, the barrier (and thus the entire trailer) is of any selected length or extendable, but the wall is “fixed” to the platforms on one side of the trailer. That side, however, can be changed to the right or left side of the road, depending on the end to which the semi tractor attaches. This dual-ended, fixed-wall design thus can eliminate the need for complex shifting or rotating designs, which are inherently weaker and more expensive, and which cannot support the visual barriers, lighting, ventilation and other amenities necessary for providing a comprehensive safety solution. The directional lighting and impact-absorbing features incorporated at each end of the trailer and in the caboose can combine with the fixed wall and improved lighting to provide increased protection for both work crews and the public, especially with ever-increasing amounts of night-time construction. End platforms integral to the trailer's design can minimize the need for workers to leave the protected zone and eliminate the need for separate maintenance vehicles by providing onboard hydraulics, compressors, generators and related power, fuel, water, storage and portable restroom facilities. Optional overhead protection can be extended out over the work area for even greater environmental relief (rain or shine). The fixed wall itself can be made of any rigid material, such as steel. Lighter weight materials having high strength are typically disfavored as their reduced weight is less able to withstand, without significant displacement, the force of a vehicular collision. The trailer can carry independent directional and safety lighting at both ends and will work with any standard semi tractor. Optionally, an impact-absorbing caboose can be attached at the end of the trailer opposite the tractor to provide additional safety lighting and impact protection.
[0047] In one aspect, the trailer is designed to provide road maintenance personnel with improved protection from ongoing, oncoming and passing traffic, to reduce the ability of passing traffic to see inside the work area (to mitigate rubber-necking and secondary incidents), and to provide a fully-contained, mobile, enhanced environment within which the work crews can function day or night, complete with optional power, lighting, ventilation, heating, cooling, and overhead protection including extendable mesh shading for sun protection, or tarp covering for protection from rain, snow or other inclement weather.
[0048] Platforms can be provided at both ends of the trailer for hydraulics, compressors, generators and other equipment and supplies, including portable restroom facilities. The trailer can be fully rigged with direction and safety lighting, as well as lighting for the work area and platforms. Power outlets can be provided in the interior of the work area for use with construction tools and equipment, with minimal need for separate power trailers or extended cords. Both the caboose and the center underside of both end platforms can provide areas for fuel, water and storage. Additional fuel, water and miscellaneous storage space can be provided in an optional extended caboose of like but lengthened design.
[0049] In one aspect, the trailer is designed to eliminate the need for separate lighting trucks or trailers, to reduce glare to traffic, to eliminate the need for separate vehicles pulling portable restroom facilities, to provide better a brighter, more controlled work environment and enhanced safety, and to, among other things, better facilitate 24-hour construction along our nation's roadways. Other applications include but are not limited to public safety, portable shielding and shelter, communications and public works. Two or more trailers can be used together to provide a fully enclosed inner area, such as may be necessary in multi-lane freeway environments.
[0050] With significant shifts to night construction and maintenance, the trailer, in one aspect, can provide a well-lit, self-contained, and mobile safety enclosure. Historical cones can still be used to block lanes, and detection systems or personnel can be used to provide notice of an errant driver, but neither offers physical protection or more than split second warning for drivers who may be under the influence of alcohol or intoxicants, or who, for whatever reason, become fixated on the construction/maintenance equipment or lights and veer into or careen along the same.
[0051] The trailer can provide an increased level of physical protection both day and night and workers with a self-contained and enhanced work environment that provides them with basic amenities such as restrooms, water, power, lighting, ventilation and even some possible heating/cooling and shelter. The trailer can also be designed to keep passing motorists from seeing what is going on within the work area and hopefully facilitate better attention to what is going on in front of them. Hopefully, this will reduce both direct and secondary incidents along such construction and maintenance sites.
[0052] Embodiments of this invention can provide a safety trailer with semi-tractor hookups at both ends and a safety wall that is fixed to one side of the trailer. That side, however, can be changed to the right or left side of the road, depending on the end to which the semi-tractor attaches. A caboose can be attached at the end of the trailer opposite the tractor to provide additional lighting and impact protection. Optionally, the trailer can be equipped with overhead protection, lighting, ventilation, onboard hydraulics, compressors, generators and other equipment, as well as related fuel, water, storage and restroom facilities and other amenities.
[0053] These and other advantages will be apparent from the disclosure of the invention(s) contained herein.
[0054] As used herein, “at least one”, “one or more”, and “and/or” are open-ended expressions that are both conjunctive and disjunctive in operation. For example, each of the expressions “at least one of A, B and C”, “at least one of A, B, or C”, “one or more of A, B, and C”, “one or more of A, B, or C” and “A, B, and/or C” means A alone, B alone, C alone, A and B together, A and C together, B and C together, or A, B and C together.
[0055] It is to be noted that the term “a” or “an” entity refers to one or more of that entity. As such, the terms “a” (or “an”), “one or more” and “at least one” can be used interchangeably herein. It is also to be noted that the terms “comprising”, “including”, and “having” can be used interchangeably.
[0056] The preceding is a simplified summary of the invention to provide an understanding of some aspects of the invention. This summary is neither an extensive nor exhaustive overview of the invention and its various embodiments. It is intended neither to identify key or critical elements of the invention nor to delineate the scope of the invention but to present selected concepts of the invention in a simplified form as an introduction to the more detailed description presented below. As will be appreciated, other embodiments of the invention are possible utilizing, alone or in combination, one or more of the features set forth above or described in detail below.
BRIEF DESCRIPTION OF THE DRAWINGS
[0057] FIGS. 1A-1E show a loaded trailer, in accordance with embodiments of the present invention;
[0058] FIGS. 2A-2C show a deployed protective wall, in accordance with embodiments of the present invention;
[0059] FIGS. 3A-3C show a wall section in accordance with embodiments of the present invention;
[0060] FIGS. 4A-4H show a platform and its components in accordance with embodiments of the present invention;
[0061] FIGS. 5A-5B show a caboose, in accordance with embodiments of the present invention;
[0062] FIGS. 6A-6G show a truck mounted attenuator attached to the caboose shown in FIGS. 5A-5B ;
[0063] FIG. 7 shows an interconnection member between a platform and a truck mounted attenuator;
[0064] FIG. 8 shows a forced air system, in accordance with embodiments of the present invention;
[0065] FIG. 9 shows the loaded trailer, including a storage compartment;
[0066] FIG. 10 is a flow chart illustrating a method of deploying a protective barrier;
[0067] FIG. 11 is a flow chart illustrating a method of balancing the weight of a protective barrier;
[0068] FIG. 12 is a flow chart illustrating a method of changing the orientation of a protective barrier/trailer;
[0069] FIG. 13 is a flow chart illustrating a method of disassembling a protective barrier and loading the component parts for transport;
[0070] FIGS. 14A-C are illustrations of a fixed wall protective barrier in accordance with alternative embodiments of the present invention;
[0071] FIG. 15A-C are illustrations of a fixed wall protective barrier in accordance with another alternative embodiment of the present invention;
[0072] FIG. 16 shows a configuration of the caboose according to an embodiment;
[0073] FIG. 17 shows a configuration of the caboose according to an embodiment; and
[0074] FIG. 18 shows a configuration of the caboose according to an embodiment.
DETAILED DESCRIPTION
[0075] Embodiments of the present invention are directed to a mobile traffic barrier. In one embodiment, the mobile traffic barrier includes a number of inter-connectable wall sections that can be loaded onto a truck bed. The truck bed itself includes two (first and second) platforms. Each platform includes a king pin (not shown); the king pin providing a connection between the selected platform and either a caboose or a tractor. By enabling the tractor to hook at either end, the trailer can incorporate a rigid fixed wall that is open to the right or left side of the road, depending on the end to which the tractor is connected. The side wall and the ends of the trailer define a protected work area for road maintenance and other operations. The tractor and caboose may exchange trailer ends to change the side to which the wall faces. The dual-hookup, fixed-wall design can enable and incorporate compartments (in the platforms) for equipment and storage, onboard power for lighting, ventilation, and heating and/or cooling devices and power tools, and on-board hydraulics for hydraulic tools. The design can also provide for relatively high shielding from driver views, and in general, a larger and better work environment, day or night.
[0076] Referring initially to FIG. 1A , a trailer in accordance with an embodiment is generally identified with reference numeral 100 . The trailer 100 includes two (first and second) platforms 104 a,b and a number of wall sections 108 a - c . As described in greater detail below, the wall sections 108 a - c are adapted to interconnect to each other and to the platforms 104 a,b to form a protective wall. In FIG. 1A , the wall sections 108 a,b are disconnected from each other and secured in a stored position on top of the interconnected platforms 104 a,b . In this position, the trailer 100 is configured so that it may be transported to a work site. In the transport configuration illustrated in FIG. 1A , the platforms 104 are bolted to each other to form a truck bed that is operable to carry the wall sections 108 and other components.
[0077] In addition to the wall sections 108 a - c , the platforms 104 a,b carry two rectangular shaped ballast members 112 a,b , which are shown as boxes of sand. As will be appreciated, the ballast members can be any other heavy material. The weights of ballast boxes 112 a,b counter balance the weights of the wall sections 108 a - c , when the wall sections 108 a - c are deployed to form a protective barrier and when being transported atop the platforms. The ballast boxes 112 a,b hold between about 5,000 and 8,000 lbs. of weight, particularly sand. At 8,000 lbs., the ballast boxes 112 a,b counter balance three wall sections 108 a - c , when the wall sections are deployed or being transported. In one configuration, the wall sections 108 a - c weigh approximately 5,000 lbs. each.
[0078] The truck bed formed by the interconnected platforms 108 a,b is connected at one end to a standard semi-tractor 116 and at the other end to an impact-absorbing caboose 120 . Both of the platforms 108 a,b include a standard king pin connection to the tractor 116 or caboose 120 , as the case may be. The caboose 120 may include an impact absorbing Track Mounted Attenuator (“TMA”) 136 , such as the SCORPION™ manufactured by TrafFix Devices, Inc. In accordance with alternative embodiments, the caboose 120 and/or tractor 116 may include a rigid connection to the rear platform 104 .
[0079] FIG. 1B shows a reverse side of the trailer 100 shown in FIG. 1A . Each platform 104 a,b includes at least one storage compartment 124 . The doors 128 to the storage compartment 124 are shown in FIG. 1A . The reverse perspective of FIG. 1B shows a rigid wall 132 forming the rear of the storage compartment 124 .
[0080] FIG. 1C shows a rear view of the trailer 100 . In FIG. 1C , the TMA 136 is shown in its retracted position. FIG. 1D shows a rear view of the trailer 100 with the TMA 136 in a deployed position.
[0081] FIG. 1E shows a top plan view of the trailer 100 . As can also be seen in FIGS. 1D and 1E , the trailer 100 includes three wall sections 108 stored on top of the platforms 104 a,b . Two of the wall sections 108 a,b nearest the right side of the trailer are positioned end-to-end, with one being positioned on top of each platform. The third wall section 108 c is positioned between the wall sections 108 a,b and the ballast boxes 112 and is approximately bisected by the longitudinal axis A of the trailer (or the first and second platforms). Effectively, by substantially co-locating the longitudinal axis of the third wall section 108 c with the longitudinal axis A of the trailer, the weight of the third wall section 108 c is effectively counter-balanced. The weight of ballast box 112 a therefore counterbalances effectively the first wall section 104 a and ballast box 112 b counterbalances effectively the second wall section 104 b . The platforms 104 a,b are asymmetrical with respect to the longitudinal axis A. Accordingly, the weights of the ballast boxes can be greater than the weights of the wall sections to counter balanced the asymmetrical portion of the platforms. The loading of the trailer shown in FIG. 1E thus serves to balance the weight of the various trailer components with respect to the longitudinal axis A.
[0082] Referring now to FIG. 2A , the trailer 100 is shown in its unloaded or deployed configuration. As can be seen in FIG. 2A , the wall sections 108 a - c have been removed from their loaded positions on top of the platforms 104 a,b and connected between the platforms 104 a,b to form a protective barrier 200 . This is accomplished by removing the wall sections 108 a - c , such as for example through the use of cranes or a forklift, and then disconnecting the two platforms 104 a,b from each other. After the platforms 104 a,b have been disconnected, the platforms 104 a,b are spatially separated and the wall sections 108 a - c are then inserted there-between. As can be seen in FIG. 2A , the two ballast boxes 112 a,b remain in place on top of the platforms 104 a,b . The ballast boxes provide a counter-balance to the weight of the wall sections 108 a - c , which are disposed on the opposite side of the platforms 104 a,b.
[0083] FIG. 2A shows a view of the protective barrier 200 from the perspective of the protected work zone area. From the protected work zone, the storage compartment doors 128 and other equipment are accessible. The protected work zone area 204 can seen in FIG. 2B , which shows a top plan view of the protective barrier 200 shown in FIG. 2A . As can be seen, the protective barrier creates a protected work area 204 , which includes a space adjacent to the wall sections 108 a - c and between the platforms 104 a,b . The road or other work surface is exposed within the work zone area 204 . The work zone area 204 is sufficiently large for heavy equipment to access the work surface.
[0084] FIG. 2C shows the traffic-facing side of the protective barrier 200 . As can be seen in FIG. 2C , the protective barrier 200 presents a protective wall 208 proximate to the traffic zone. The protective wall 208 includes the rigid wall 132 and number of wall sections 108 a - c , which are interconnected to the two platforms 104 a,b . The bottoms of the wall sections 108 a - c are elevated a distance 280 above the roadway 284 . FIGS. 5A-B additionally show a portion of the caboose 120 , which interconnects to and is disposed underneath a selected one of the platforms 104 a,b . The wheels of the caboose 120 , in the deployed position of the trailer 100 shown in FIG. 2C , are covered with a piece of sheet metal 212 . During transport, this piece of sheet metal 212 can be disconnected from the platform 104 and positioned in a stowed manner on top of one of the platforms 104 .
[0085] Although stands 290 are shown in place at either end of the protective barrier 200 and may be used to support individual wall sections 108 of the barrier 200 , it is to be understood that no stands are required to support the barrier 200 . The barrier 200 has sufficient structural rigidity to act as a self-supporting elongated beam when supported on either end by the tractor 116 and caboose 120 . This ability permits the barrier 200 to be located simply by locking the tractor and caboose brakes and relocated simply by unlocking the brakes, moving the barrier 200 to the desired location, and relocking the brakes of the tractor and caboose. Requiring additional supports or stands to be lowered as part of barrier 200 deployment can not only immobilize the barrier 200 but also increase barrier rigidity to the point where it may cause excess damage and deflection to a colliding vehicle and excess ride down and lateral G forces to the occupant of the vehicle.
[0086] The wall section height is preferably sufficient to prevent a vehicle colliding with the barrier 200 from flipping over the wall section into the work area and/or the barrier 200 from cutting into the colliding vehicle, thereby increasing vehicle damage and lateral and ride-down G forces to vehicular occupants. Preferably, the height of each of the wall sections is at least about 2.5 feet, more preferably at least about 3.0 feet, even more preferably at least about 3.5 feet, and even more preferably at least about 4.0 feet. Preferably, the height of the top of each wall section above the surface of the ground or pavement 284 is at least about 3.5 feet, more preferably at least about 4 feet, even more preferably at least about 4.5 feet, and even more preferably at least about 5 feet.
[0087] The protective wall or barrier 200 may additionally include attachment members 216 operable to interconnect a visual barrier 220 to the protective wall 200 . A visual barrier 220 in accordance with embodiments is mounted to the protective wall 200 and extends from the top of the protective wall 200 to approximately four feet above the wall 200 . The visual barrier 220 is interconnected to attachment members 216 , such as poles, which are interconnected to the wall 200 . In accordance with an embodiment, the attachment members 216 comprise poles which extend 10 feet upwardly from the wall section 200 . Each pole may support a 6 lb. light head at the top which generates over 3,000 alums of light. The poles may additionally provide an attachment means for the visual barrier 220 . While attached to the poles, the visual barrier 220 extends approximately 4 feet upwardly from the protective wall 200 .
[0088] The visual barrier 220 provides an additional safety factor for the work zone 204 . Studies have shown that a major cause of highway traffic accidents in and around work zone areas is the tendency for drivers to “rubber-neck” or look into the work zone from a moving vehicle. In this regard, it is found that such behavior can lead to traffic accidents. In particular, the “rubber-necking” driver may veer out of his or her traffic lane and into the work zone, resulting in a work zone incursion. The present invention can provide a structurally rigid wall 200 that prevents incursion into the work zone 204 , as well as a visual barrier 220 which discourages this, so called, “rubber necking” behavior.
[0089] Studies have indicated that people are drawn to lights and distractions, and that they tend to steer and drive into what they are looking at. This is particularly hazardous for construction workers, especially where cones and other temporary barriers are being deployed on maintenance projects. Studies also indicate that lighting and equipment movement within a work zone are important factors in work site safety. Significant numbers of people are injured not only from errant vehicles entering the work zone, but also simply by movement of equipment within the work area. The trailer can be designed not only to keep passing traffic out of the work area, but also to reduce the amount of vehicles and equipment otherwise moving around within the work area.
[0090] In terms of lighting, research indicates more is better. Current lighting is often somewhat removed from the location where the work is actually taking place. Often, the lighting banks are on separate carts which themselves contribute to equipment traffic, congestion and accidents within the job site.
[0091] These competing considerations of motorists, at night, steering towards lights and roadside workmen being safer at night with more lighting can be satisfied by the trailer. The trailer can use the light heads 270 to provide substantial lighting where it is needed. If the work moves, the lighting moves with the work area, rather than the work area moving away from the lighting. Most importantly, the safety barrier—front, back and side—can move along too, providing simple but effective physical and visual barriers to passing traffic. Referring to FIGS. 2B and 2C , the light heads 270 positioned along the barrier 200 have a direction of illumination that is approximately perpendicular or normal to the direction of oncoming traffic. This configuration provides not only less glare to oncoming motorists but also less temptation for motorists to steer towards and into the barrier 200 .
[0092] FIGS. 2A-2C show the protective barrier 200 deployed for use in connection with a work-zone area. The design of the support members and the traffic facing portion of the protective barrier 200 , serve to provide a safe means for mitigating the effects of such a collision. In particular, the barrier 200 can re-direct the impacted moving car down the length of the protective wall 208 . Here, the moving car is not reflected back into traffic. Further incidents are prevented by not reflecting the moving car back from the mobile barrier into other cars, thereby enhancing safety not only of the driver of the vehicle colliding with the barrier but also of other drivers in the vicinity of the incident. The inherent rock/roll movement in the tractor 116 and trailer (caboose) springs and shocks assist dissipation of shock from vehicular impact. In addition, by deflecting the moving vehicle down the length of the protective wall 208 , the work zone 200 is prevented from sustaining an incursion by the moving vehicle, thereby enhancing safety of workers.
[0093] A number of factors are potentially important in maintaining this desirable effect. Firstly, the protective barrier 204 is maintained in a substantially vertical position. This is accomplished through a ballasting system and method in accordance with an embodiment. In particular, the wall sections 108 are balanced in a first step with the ballast boxes 112 . In a following step, a more precise balancing of the protective barrier 200 position is achieved through a system of movable pistons associated with the caboose 120 . This aspect of the invention is described in greater detail below. Second, the structural design of the wall sections 108 serve to provide optimal deflection of an incoming car. Finally as shown in FIG. 2B , the protective wall or barrier 200 is substantially planar and smooth (and substantially free of projections) along its length to provide a relatively low coefficient of friction to an oncoming vehicle. As will be appreciated, projections can redirect the vehicle into the wall and interfere with the wall's ability to direct the vehicle in a direction substantially parallel to the wall.
[0094] Turning now to FIG. 3A , an individual wall section 108 is shown in perspective view from the traffic side of the wall section 108 . As can be seen in FIG. 3A , the wall section 108 includes a wall skin portion 300 , which faces the traffic side of the protective barrier 200 and is smooth to provide a relatively low coefficient of friction to a colliding vehicle. The wall skin 300 is adapted to distribute the force of the impact along a broad surface, thereby absorbing substantially the impact. As additionally can be seen in FIG. 3A , the wall section 108 includes a first end portion or wall end member 304 a . The first end portion 304 a includes a conduit box 308 , a number of bolt holes 312 , a protruding alignment member, which is shown as a large dowel 316 a , and an alignment receiving member, which is shown as a small dowel receiver hole 320 a . As will be appreciated, the alignment member can have any shape or length, depending on the application. The first end portion 304 a of the wall section 108 is adapted to be interconnected to a second end portion 304 b of an adjacent wall section 108 or platform 104 . A second end portion 304 b can be seen in FIG. 3B , which shows the opposite end 304 b of the wall section 108 shown in FIG. 3A , including a protruding small dowel 316 b and a large dowel receiver hole 320 b . For each wall section 108 , the large dowel 316 a disposed on the top of the first end portion 304 a is operatively associated with a large dowel receiver hole 320 b in the second end portion 304 b of an adjacent wall section 108 or platform 104 . Similarly, the small dowel 316 b on the second end portion 304 b is operatively associated with the small dowel receiver hole 320 a in the first end portion 304 a of an adjacent wall section 108 or platform 104 . Additionally, the wall sections 108 are interconnected through a screw-and-bolt connection using the bolt holes 312 associated with the wall ends 304 . The conduit box 308 is additionally aligned with an adjacent conduit box 308 , providing a means for allowing entry and pass-through of such components as electrical lines, air hoses, hydraulic lines, and the like.
[0095] In FIG. 3B , a portion of the wall skin 300 is not shown in order to reveal the interior of the wall section 108 . As can be appreciated, such a partial wall skin 300 is shown here for illustrative purposes. As can be seen in FIGS. 3B and 3C , the wall section 108 includes three bracing sections 324 a - c vertically spaced equidistant from one another. Each of the bracing sections 324 includes two opposing horizontal beams 328 a - b , with the free ends being connected to the adjacent wall end member 304 a,b . The two horizontal beams 328 a - b are interconnected with angled steel members 332 to form a truss-like structure. The wall section 108 includes three bracing sections: the first bracing section 324 a being at the top, the second bracing section 324 b being at the middle and the third bracing section 324 c being at the bottom. Additionally, the wall section 108 includes a number of full-height vertical wall sections 336 a,b , the wall end members 304 a,b , and a number of partial-height vertical wall sections 340 a - c . As shown in FIG. 3A , the full-height wall sections 336 a,b and partial-height wall sections 340 a - c alternate. Additionally, it can be seen that the angled steel members 332 intersect at points where the partial-height wall 340 or full height wall 336 section, as the case may be, meets the horizontal beam 328 a,b , which, on one side, faces the traffic side of the wall section 108 . Additionally, the wall section includes a fourth horizontal member 344 . Unlike the structural members 328 and 336 which are preferably configured as rectangular steel beams, this fourth horizontal member 344 is configured as a steel C-channel beam. The C-channel is preferably positioned substantially at the height of a car or SUV bumper. In use, the bottom of the wall section 108 sits approximately eleven inches off of the ground, and the fourth horizontal member 344 sits approximately twenty inches off of the ground.
[0096] The wall sections 108 constructed as described and shown herein are specifically adapted to prevent gouging of the wall as a result of an impact from a moving car. In particular, gouging as used herein refers to piercing or tearing or otherwise drastic deformation of the wall section, which results in transfer of energy from a moving car into the mobile barrier 200 . As described herein, by deflecting the car down the length of the protective wall 200 , a desirable amount of energy is absorbed by the wall and therefore not transferred to other portions of the protective wall 200 . It is additionally noted that the floating king pin plate of the standard trailer 116 provides a shock absorbing effect for impacts which are received by the protective wall 200 . The shock absorbing effect of the trailer's 116 floating king pin plate 500 is complemented by fixed king pin plate associated with the caboose 120 (which is discussed below).
[0097] In accordance with an embodiment, the dimensions of the various trailer and wall components vary. By way of example, the length of each wall section 108 preferably ranges from about 10 to 30 feet in length, more preferably from about 15 to 25 feet in length, and more preferably from about 18 to 22 feet in length. The width of each of the wall sections preferably ranges from about 18 to 30 inches, more preferably from about 22 to 28 inches, and more preferably from about 23 to 25 inches. The height of each of the wall sections 108 preferably ranges from about 3 to 4.5 feet, more preferably from about 3.75 to 4.25 feet, and more preferably from about 3.9 to 4.1 feet. It should be noted that these height ranges and distances measure from the base of a wall section 108 to the top of the wall section 108 and do not include the wall section's height when it is displaced with respect to the ground. In use, the wall section 108 typically is disposed at a predetermined distance from the ground. In particular, this distance preferably ranges from about 10 to 14 inches, more preferably from about 11 to 13 inches, and more preferably from about 11.5 to 12.5 inches. In accordance with an embodiment, a wall section is approximately 20 feet long, 24 inches wide, 4 feet high as measured from the base of the wall section to the top of the wall section and, when deployed, disposed at a distance of 12 inches from the ground.
[0098] The beams 328 a and 328 b span the length of the entire wall section. In accordance with an embodiment, the horizontal beams 328 a and 328 b measure from about 3-5 inches by about 5-7 inches, more preferably from about 3.5 inches to 4.5 inches by 5.5 inches to 6.5 inches, and even more preferably are about 4 inches by 6 inches. In accordance with an embodiment, the longer dimension of the beam is disposed in the horizontal direction. For example, with 4.times.6 beams, the 4-inch dimension is disposed in the vertical direction and the 6-inch dimension in the horizontal direction. In this embodiment with three sets of horizontal beams, the bottom and middle beams are separated by about 18 inches and the middle and the top beams also by about 18 inches. In this configuration, the total height of the wall section is 4 feet. In other portions of the mobile barrier 200 , the orientations of the horizontal beams may differ. In particular, the longer 6 inch dimension may be in the vertical direction, and the shorter 4 inch dimension may be in the horizontal direction. In accordance with an embodiment, this orientation for the horizontal beams is implemented in connection with the platforms 104 .
[0099] The wall skin 300 may be comprised of a single homogeneous piece of steel that is welded to the wall section 108 . The wall skin 300 is preferably between about 0.1 and 0.5 inch thick, more preferably between about 0.2 and 0.4 inch, and even more preferably approximately 0.25 inches thick. These dimensions are also applicable to the partial-height and full height wall members 340 , 336 . The wall end portions or plates 304 b and 304 a are preferably between about 0.25 and 1.25 inch thick, more preferably between about 0.5 and 1 inch thick, and even more preferably are about 0.75 inch thick.
[0100] In accordance with a preferred embodiment where the wall sections 108 are approximately 20 feet in length, a work space area 204 is defined when these wall sections are deployed that measures approximately 80 feet in length. In particular, the three wall sections total 60 feet in addition to 10 feet on each side of additional space provided by the interior portions of the platforms 104 .
[0101] Referring again to FIG. 3C , a wall section 108 may include a number of attaching devices, which provide a means for interconnecting various auxiliary components to the wall section 108 . In particular, a wall section 108 may include an attachment member mounting 348 , operable to mount an attachment member 216 , such as a pole. The attachment member mounting shown in FIG. 3C includes a lever which, through a quarter turn, is operable to lock the light pole in place. A pole may be used to mount a light in connection with using the wall barrier during night-time hours. As can be appreciated in such conditions, the work area will be required to be illuminated. Such illumination can be accomplished by light poles and corresponding lights which are mounted to the wall section. The light poles, lights and other auxiliary components may be stored in the storage compartments 124 .
[0102] The wall section 108 additionally may include attachments for jack stands 352 . The jack stands 352 provide a means for supporting the wall section 108 at the above-mentioned height of approximately eleven inches from the ground.
[0103] The wall section 108 may additionally include, so called, “glad hand boxes” (not shown), which provide means for accessing 12, 110, 120, 220, and/or 240 volt electricity. In accordance with the embodiments, the protective barrier 200 includes an electric generator and/or one or more batteries (which may be recharged by on-board solar panels) providing electricity which is accessible through the glad hand box and is additionally used in connection with other components of the protective barrier 200 described herein. The generator and/or the batteries may additionally be stored the storage compartments 124 , and the batteries used to start the generator and support electronics when the generator is turned off or is not operational.
[0104] The wall section 108 may be comprised of, or formed from, any suitable material which provides strength and rigidity to the wall section 108 . In accordance with embodiments, the beams of the wall section are made of steel and the outer skin of the wall section is made from sheets of steel. In accordance with alternative embodiments, the wall section 108 is made from carbon fiber composite material.
[0105] Referring now to FIG. 4A , a side perspective view of a platform 104 is shown. In FIG. 4A the platform is resting on a jack stand 352 . Additionally, the outline of the caboose 120 is shown in FIG. 4A . With the caboose 120 attached, the platform 104 shown in FIG. 4A would correspond to the rear of the protective barrier 200 and/or the rear of the loaded trailer 100 . As can be seen in FIG. 4A , the platform includes a king pin 400 . The king pin 400 provides an interconnection between the platform 104 and the caboose 120 . The king pin 400 is disposed on the underside of the platform 104 in a position that allows the king pin 400 to connect with a standard floating king pin plate associated with a semi-tractor 116 or a fixed king pin plate associated with the caboose 120 . In this way, either the caboose 120 or the semi-tractor 116 may be connected to the platform 104 using the king pin 400 . A nose receiver 404 portion of the platform 104 provides a means for receiving the end, or nose portion of the caboose 120 . This aspect of the invention is described in greater detail below.
[0106] In FIG. 4B and FIG. 4C , two opposed platforms 104 are shown with a central external cover plate of the central portions of the platforms being removed to show the structural members while the ballast box external support plates are in position, in FIG. 4D , a platform is shown with all exterior cover plates removed, and in FIG. 4G a platform is shown with all external cover plates in position. As can be seen, the first end 408 of the platform 104 is wider than the second end 412 of the platform 104 . Here, the platform 104 includes support members 421 for supporting the king pin (not shown), a sloping plate 428 for receiving the nose portion of the caboose, a flat plate assembly 422 positioned above and supporting the jack stands 423 , and a sloped or narrowing section 416 , which slopes from the larger, first-end 408 width, to the smaller, second-end 412 width. This sloped portion 416 of the platforms 104 includes the storage compartment 124 . The two second-ends 412 of the platform 104 are adapted to be interconnected to each other. The two first-ends 408 of the platform 104 are adapted to interconnect to either the tractor 116 or the caboose 120 , as described above. As can be seen in FIG. 4D , the platform 104 includes two side channels 420 a - b . Typically, the channel 420 a proximate to the work zone is adapted to receive a ballast box 112 , both in the mobile and the deployed positions.
[0107] FIGS. 4D , 4 E, and 4 F further show the structural members of each of the platforms. The platforms are identically constructed but are mirror images of one another. The traffic-facing, or elongated, side 460 of the platform 104 includes upper, middle, and lower horizontal structural members 464 , 468 , and 472 . The upper, middle, and lower horizontal structural members are at the same heights as and similar dimensions to the upper, middle, and lower horizontal beams 328 , respectively. The members 464 , 468 , and 472 , unlike the beams 328 , are oriented with the long dimension vertical and the shorter dimension horizontal. By orienting the members differently from the beams, the need for a member similar to the fourth horizontal member 344 is obviated. The upper structural member 464 is part of an interconnected framework of interconnected members 476 , 480 , 484 , 488 , 490 , and 492 defining the upper level of the platform. Lateral structural members 494 provide structural support for the ballast boxes, depending on where they are positioned, and lateral members 496 provide further structural support for the upper level and for the king pin and other caboose interconnecting features discussed below. The first end of the lower structural member attaches to a corner member 497 and second ends of the upper and lower structural members to the second end member 498 . At the level of the lower structural member 472 , lower structural members 473 , 474 , 475 , and 477 define the lower level of the platform. Additional vertical and corner members 478 , 479 , and 481 attach the lower and upper levels of the platform and horizontal support member 483 interconnects corner members 497 and 481 and vertical members 478 and 479 . The lower level further includes lateral members 475 and elongated member 477 to provide further structural support for the lower level and provide support for the bottom of the storage compartment.
[0108] In FIGS. 4G and 4H , portions of the platform 104 are shown, which include the underside of a platform 104 . As can be seen in FIG. 4E , the platform 104 includes a king pin 400 disposed substantially in alignment with a longitudinal axis 405 bisecting a space 407 defined by the nose receiver portion 404 . The nose receiver portion 404 includes two angled components 424 a,b as well as a downwardly facing deflection plate 428 . FIG. 4H shows, in plan view, the components 424 a,b , each of which includes a straight portion 409 a,b and angled portion 411 a,b . The space 407 between the angled portions is in substantial alignment with the king pin 400 .
[0109] As the caboose 120 is backed into the space underneath the platform 104 , the king pin 400 is received in a king pin receiver channel 524 ( FIG. 5 ) in a fixed king pin plate on the caboose 120 , and the nose of the caboose is received in the nose receiver 404 portion of the platform 104 . The nose receiver portion 404 , namely the angled portions of the components 424 a,b and sloped deflection plate 428 , guide the an angled front-nose portion 520 ( FIG. 5 ) of the caboose as the caboose is brought into position underneath the platform 104 to align the king pin with the king pin receiver channel 524 ( FIG. 5 ). In particular, the two angled components 424 operate to provide lateral guidance for the position of the caboose 120 . Here, the two angled components 424 ensure that the king pin 400 is received in the king pin receiver channel 524 associated with the caboose 120 . The downwardly facing deflection plate 428 exerts a downward force on the nose 520 of the caboose that results in the rear of the caboose 120 raising up to engage the rear of the platform 104 . The interconnection between the caboose 120 and the rear of the platform 104 is described in greater detail below.
[0110] In FIG. 5A , a side perspective view of the caboose 120 is shown. As shown in FIG. 5A , the caboose 120 includes the fixed king pin plate 500 . The king pin plate 500 includes a king pin receiver channel 524 provided at the end of the plate 500 . This pin receiver channel 524 is adapted to receive the king pin 400 and provides a locking mechanism for locking the caboose 120 to the end of the platform 104 . In addition, the caboose 104 includes a vertical adjustment member, which is shown as movable pneumatically or hydraulically actuated piston 508 (as can be seen in FIG. 4A ), disposed on each side between the two wheels of the caboose 120 . Although a piston is shown, it is to be understood that any suitable adjustment member may be used, such as a mechanical lifting device (e.g., a jack or crank). The movable piston 508 is associated with a piston cylinder and is interconnected to a top 512 portion and a bottom portion 516 of the caboose 120 . The bottom portion 516 provides a mounting for the wheel axles as well as the wheel suspension. The movable piston 508 , as described in greater detail below, is operable to be inflated, thereby adjusting the height of the selected, adjacent side of mobile barrier 200 . More specifically, the movable piston 508 moves the caboose 120 off of its suspension or leaf springs.
[0111] In FIG. 5A , a side perspective view of the caboose 120 is shown. As can be seen in FIG. 5B , the fixed king pin plate 500 includes the king pin receiver channel 524 . The king pin receiver channel 524 includes a front, wide portion 528 , which leads into a rear, narrow portion 532 , as this king pin receiver channel 524 allows the caboose 120 to be positioned properly while the caboose is being backed into and underneath the platform 104 . In this regard, the nose 520 of the caboose 120 is additionally received in the nose receiver portion 404 , disposed on the underside of the platform 104 . This aspect of the present invention is described in greater detail below.
[0112] Referring now to FIG. 58 , an additional side perspective view of the caboose 120 is shown. In FIG. 5B , the king pin plate 500 is shown removed from the caboose 120 . As can be seen in FIG. 5B , underneath the king pin plate 500 , the caboose 120 includes a number of air cylinders 536 . These air cylinders 536 are associated with a standard ABS braking system and operate independently of the braking system of the tractor 116 . As described in greater detail below, the air cylinders 536 can be locked by an auxiliary mechanism associated with the caboose 120 to hold the caboose 120 in place. The auxiliary mechanism may be adjusted to allow the brakes to be engaged and the caboose 120 held in place even if the caboose 120 is disconnected from the platform 104 . This mechanism additionally provides a means for inflating and deflating the movable piston 508 disposed on either side of the caboose 120 .
[0113] FIGS. 5A , 5 B, and 8 depict the removable attachment mechanism between the caboose and the platform. The caboose includes permanently attached first and second pairs 580 a,b of opposing attachment members 584 a,b . Each attachment member 584 a,b in the pair 580 a,b has matching and aligned holes extending through each attachment member. In FIG. 8 , first and second pairs 804 a,b of attachment members 808 a,b are permanently attached to the platform. Each attachment member 808 a,b in the pair includes matching and aligned holes extending through the attachment member 808 . When the caboose is in proper position relative to the platform, the holes in the attachment members 584 a,b and 808 a,b are aligned and removably receive a pin 802 having a cotter pin or key 810 to lock the dowell 802 in position in the aligned holes of each set of engaged pairs of attachment members 580 and 804 .
[0114] An embodiment includes a truck mounted crash attenuator, or equivalently, a Truck Mounted Attenuator (TMA). Referring again to FIG. 1A , a truck mounted attenuator 136 is shown interconnected to the trailer 100 at the caboose 120 . In FIG. 1A , the truck mounted attenuator 136 is shown in a retracted position. The truck mounted attenuator 136 includes a first portion 140 and a second portion 144 . In the retracted position, the first portion 140 is positioned substantially vertically and supports the weight of the second portion 144 , which is held in a substantially horizontal position over the caboose 120 . A movable electronic billboard 148 and light bar 150 (which can provide a selected message to oncoming traffic) is located underneath the second portion 144 of the truck mounted attenuator 136 .
[0115] The deployment of the truck mounted attenuator 136 and the electronic billboard and light bar 148 is illustrated in FIGS. 6A-6G . As shown in FIG. 6A through FIG. 6F , the truck mounted attenuator 136 is extended and lowered into a position wherein both the first portion 140 and the second portion 144 are substantially horizontal and proximate to the ground. As shown in FIG. 6G , the electronic billboard 148 and light bar 150 are then raised. Referring to FIG. 7 , the TMA 136 is typically bolted by a bracket 700 to the caboose 120 . The TMA is thus readily removable simply by unbolting the TMA from the vertical plate of the bracket 700 . Additionally, the bracket 700 and associated components provide a means for attaching the electronic billboard 148 and light bar 150 to the caboose 120 . The bracket 700 is mounted to provide a desirable height for the truck mounted attenuator in its deployed position, more specifically, approximately ten to eleven inches off of the ground. The bracket 700 is additionally mounted to provide visibility of the caboose brake lights and other warning lights associated with the trailer 100 . In FIG. 1C , a rear view of the loaded trailer 100 is illustrated. As shown herein, the truck mounted attenuator 136 is raised into its tracked position. As can be seen, the brake lights 152 of the caboose 120 are visible underneath the truck mounted attenuator 136 . A beacon 156 is also visible, despite the presence of the truck mounted attenuator 136 . The beacon 156 provides a visual indication of an end portion of the trailer 100 . As with the caboose 120 , the truck mounted attenuator 136 may be associated with either of the two platforms 104 and thereafter either end of the trailer.
[0116] Turning now to FIG. 8 , a forced air system 800 in accordance with an embodiment is shown. The forced air system 800 includes two lever attenuators 804 operable to lock the brakes of the caboose 120 independently of the brakes of the tractor 116 . As used herein, locking the brakes includes disconnecting or disabling the automatic brake system, typically associated with the caboose 120 . Here, the brakes are forced into a locked position, thereby locking or preventing movement of the caboose 120 . Also shown in FIG. 8 is a knob 808 operable to control the inflation and/or deflation of the moveable pistons 508 . As described above, the pistons 508 are used to provide a finer grade vertical adjustment of the balancing of the protective barrier 200 by vertically lifting or lowering a selected side of the caboose and interconnected platform. In other words, inflating the piston on a first side of the caboose lifts the first side of the platform relative to the second side of the platform and vice versa. In accordance with embodiments, the air provided to the pistons 508 is delivered from an air supply associated with the trailer 116 and not from an air compressor.
[0117] The interconnection between the platform 104 and the king pin plate 500 is illustrated in FIG. 8 . A removable pin interconnects the platform to the caboose. The pin is removable, and may be locked in place with attachment member 802 .
[0118] Turning now to FIG. 9 , a loaded trailer 100 is shown from the work area-side of the trailer 100 . As shown herein, the wall sections 108 are loaded on top of the platforms 104 and the platforms 104 are interconnected. As described above, this loaded position corresponds to an arrangement of the various components, which can be used to transport the entire system. As shown in FIG. 9 , the platform includes a storage compartment. Various auxiliary components described herein are stored in this storage compartment 124 . As can be seen in FIG. 9 , such components, as the light poles 900 , the corresponding lights themselves 904 , the visual barrier 220 , as well as various electrical components, are shown inside of the compartment. For example, FIG. 9 includes an onboard computer 908 and a generator 912 . In this configuration or in the deployed configuration, various lines 916 , such as electrical lines or air lines, may run along the length of a wall section 108 through the various adjacent conduit boxes 308 .
[0119] Referring now to FIG. 10 , a flow chart is shown which illustrates the steps in a method of deploying a mobile barrier in accordance with an embodiment. Initially at step 1004 , the trailer arrives at a worksite. At step 1008 , the wall sections 108 are unloaded from the trailer bed. This may be done with the use of cranes, a fork lift, and/or other heavy equipment operable to remove and manipulate the weight associated with the wall sections 108 . At step 1012 , the platforms 104 are disconnected from each other. More particularly, the bolt connections that interconnect the platforms 104 are removed. At step 1016 , the platforms 104 are separated. Here, the brakes of the caboose 120 may be locked and the disconnected platform portion of the trailer 116 attached to the tractor 116 may be driven away from the location of the caboose 120 and its attached platform. A dolly or castor wheel may be connected to the end of the platform 104 to provide mobility for the portion of the platform 104 attached to the tractor 116 , thereby allowing the platform to move into position to be engaged with the end wall section. Alternatively, a first platform connected to the tractor 116 is positioned at the desired location before disconnection of the platforms. Jacks attached to the first platform are lowered into position with the roadway. The platforms are then disconnected, with the second platform being supported by the caboose. A forklift or other vehicle is used to move the second platform into position for connection with the wall sections. In any event at step 1020 , the platforms 104 and wall sections 108 are interconnected to form a protective barrier 200 . At this point a continuous protective barrier 200 is formed from the various components of the trailer. Next, a number of steps or operations may be employed. At step 1024 , it may be determined that the protective barrier 200 must be balanced. More particularly, the weight of the protective barrier 200 must be adjusted such that the protective barrier 200 wall comes into a substantially vertical alignment. If no balancing of the protective barrier 200 is needed, work may be commenced within the protected area 204 of the protective wall 200 . At step 1028 , it may be determined that the direction or orientation of the protective barrier 200 may need to be changed. This may be done by jacking the second platform, disconnecting the caboose, and reversing the positions of the tractor 116 and caboose 120 . Alternatively, the jack stands may be retracted and the truck, while the wall sections are deployed, driven, while attached to the barrier, to a new location. At step 1032 , work may be completed and the protective barrier 200 may then be disassembled for transport.
[0120] Turning now to FIG. 11 , a method of balancing a protective barrier 200 (step 1024 ) is illustrated. This method assumes that the ballast boxes are not adequate to counter-balance completely the deployed barrier. At step 1104 , the protective barrier 200 or wall is inspected to determine whether or not the wall is disposed at a substantially vertical orientation. This can be done using a manual or automatic level detection device. If at decision 1108 the wall is substantially vertical, step 1112 follows. At step 1112 the process may end. If at decision 1108 , it is determined that the wall is not substantially vertical, step 1116 follows. At step 1116 , one or more of the piston cylinders 508 are inflated or deflated to provide a counter balance to the weight of the protective barrier 200 and desired barrier 200 orientation.
[0121] FIG. 12 illustrates a method of changing directions for the protective barrier 200 . Initially, at step 1204 , the caboose-engaging platform is placed on jack stands and thereafter the caboose is disconnected from the platform to which it is attached. At step 1208 , the caboose is towed out from underneath the platform 104 . Here, the caboose 120 may be connected to or otherwise attached to a tractor, forklift, or pickup truck, which is operable to tow the caboose 120 . At step 1220 , the tractor-engaging platform is placed on jack stands and the tractor 116 is disconnected from the platform 104 to which it is attached. At step 1216 , the tractor 116 is driven out from underneath the platform 104 . At step 1220 , the positions of the caboose 120 and tractor 116 are interchanged. At 1224 , the caboose 120 is positioned underneath and connected to the platform 104 to which the tractor 104 was formally attached. As described above, this includes a nose receiver portion 404 , providing guidance to the caboose 120 in order to guide the king pin 400 into the king pin receiver channel 532 associated with the king pin plate. At step 1228 , the tractor 116 is positioned with respect to and connected to the platform 104 to which the caboose 120 was formally attached.
[0122] Referring now to FIG. 13 , a method of loading a trailer in accordance with embodiments is illustrated. Initially at step 1304 , the platforms 104 and wall sections 108 are placed on jack stands and disconnected from one another. This includes removing the bolt connections which interconnect the opposing faces of the platforms 104 and/or wall sections 108 . At step 1308 , the platforms 104 are brought together. As described above, this includes interconnecting a castor or dolly wheel to at least one platform end and driving the platform 104 in the direction of the opposing platform. Alternatively, the platform engaging the caboose is taken off of its jack stands and maneuvered by a vehicle to mate with the other, stationary platform. At step 1312 , the platforms 104 are interconnected by such means as bolting the platforms together. At step 1316 , the wall sections 108 are loaded onto the truck bed. Because the ballast boxes typically do not counter-balance precisely the loaded wall sections and vice versa, the piston cylinders 508 are inflated or deflated, as desired, to provide a level ride of the trailer. Finally, at step 1320 , the trailer 100 departs from the worksite. In one configuration, castor or dolly wheels may be put on each of the two platforms so that, when they are disconnected from end wall sections of the barrier, the first and second platforms may be moved into engagement with and connected to one another. The wall sections may then be disconnected from one another and loaded onto the connected platforms.
[0123] The above discussion relates to a mobile barrier in accordance with an embodiment that includes a number of interconnectable wall sections, which are, in one configuration placed on the surface of a truck bed. In a second configuration, these wall sections are removed from the truck bed and interconnected with portions of the trailer to form a protective barrier. In this way, a fixed wall is formed that provides protection for a work area. The present invention can provide a non-rotating wall that is deployed to form the protective barrier. Alternative embodiments of a fixed wall mobile barrier are illustrated in FIGS. 14A-C and FIGS. 15A-C .
[0124] FIGS. 14A-C illustrate a “sandwich” type extendable protective wall. As shown in FIG. 14A , the mobile barrier 1400 includes two platforms 104 and three interconnected wall sections 1404 a , 1404 b and 1404 c . FIG. 14A illustrates a contracted or retracted position wherein the wall sections 1404 a - c are disposed adjacent to one another in a “sandwich position”. FIG. 14B illustrates an intermediate step in the deployment of the mobile barrier 1400 . Here, the platforms 104 are moved away from each other and the sandwiched wall sections extended. From this intermediate position, the sections 1404 a and 1404 c move forward to a position adjacent to the forward position of the wall section 1404 a . In accordance with embodiments, the wall sections 1404 a - c are disposed on sliding rails which allow the displacement shown in FIG. 14B-C . Additionally between wall sections 1404 a and 1404 a (similarly 1404 b and 1404 c ) an articulating mechanism is provided, which allows motion between the adjacent wall sections. FIG. 14C shows the final position of the mobile barrier 1400 . Here, the various wall sections 1404 a - c and the platforms 104 provide a continuous mobile barrier included a protected work space.
[0125] FIGS. 15A-15C illustrate a telescoping type protective wall system 1500 . FIG. 15A shows a retracted, or closed, position of the protective barrier 1500 . The protective barrier includes opposing platforms 104 . The protective barrier in this embodiment includes two wall sections, the first wall section 1504 encloses the second wall section 1508 in the contracted position shown in FIG. 15A . In the intermediate position shown in FIG. 15B , the second wall section 1508 is extended outward from the first wall section 1504 in a telescopic manner. In the final position shown in FIG. 15C , the second wall section 1508 moves forward to a position adjacent to the first wall section 1504 . In the final position shown in FIG. 15C , the first wall section 1504 , second wall section 1508 and portions of the two platforms 104 form a continuous protective barrier including protective interior space.
[0126] A number of alternative caboose embodiments will now be discussed.
[0127] Referring to FIG. 16 , the caboose 1600 has one or more steerable or articulating axles 1604 a,b or wheels 1608 a - d to avoid a selected area 1612 , such as a work area containing wet concrete. The wheels 1608 a - d are turned to a desired orientation, which is out of alignment with the tractor 116 tires, so that, when the trailer is pulled forward by the tractor 116 , the trailer moves both forward and laterally out of alignment with the path of movement of the tractor 116 . This may be effected in many ways. In one configuration, steering arms (not shown) are attached to the axles 1604 , and the arms are controlled by electrically operated hydraulic cylinders incorporated into the caboose frame assembly. The caboose axles are turned out when pulling ahead to more quickly move the rear of the trailer out and away from the area 1612 . Once the tractor and trailer are out of alignment with the area 1612 , the axles are returned, such as by the hydraulics, to their original positions in alignment with the tractor wheels. The electronics controlling the hydraulics are controlled from the tractor cab or a special switch assembly located in the caboose or on the trailer near the caboose. Alternatively, the axles or wheels may be steered manually, such as by a steering wheel mounted on the platform or caboose. The nose portion of the caboose remains stationary in the members 404 a,b , or the caboose does not rotate about the kingpin but remains aligned with the longitudinal axis of the trailer throughout the above sequence.
[0128] Referring to FIG. 17 , the caboose 1700 articulates or rotates about the king pin 400 . One or more electrically driven hydraulic cylinders at the front of the caboose laterally displaces the nose 1704 in a desired orientation relative to the longitudinal axis of the trailer. When the caboose is rotated to place the wheels 1708 a - d in a desired orientation, which is out of alignment with the tractor 116 tires, the tractor pulls the trailer forward. The trailer moves both forward and laterally out of alignment with the path of movement of the tractor 116 . The hydraulics then push the nose of the caboose to the aligned, or normal, orientation in which the wheels of the caboose are in alignment with the wheels of the tractor. The hydraulic cylinder(s) can be connected directly to a front pivot (not shown) or incorporated into the nose portion or the current “V” wedge assembly, which includes the members 404 a,b . In the latter design, the members 404 a,b are mounted on a movable plate, and the hydraulic cylinder(s) move the plate to a desired position while the nose portion 1704 is engaged by, or sandwiched between, the members 404 a,b . Unlike the prior caboose embodiment, the caboose rotates about the kingpin and does not remain aligned with the longitudinal axis of the trailer throughout the above sequence.
[0129] Referring to FIG. 18 , the caboose 1800 has an elongated frame with articulated steering on one or more axles 1804 a - c , with the rear axle 1804 a being preferred. When only the rear axle is steerable, the axle 1804 a is steered, as noted above, to place the wheels 1808 a,b in the desired orientation. After the caboose is rotated to place the wheels 1808 a,b in a desired orientation, which is out of alignment with the tractor 116 tires, the tractor pulls the trailer forward. The trailer rotates about the king pin 400 and moves both forward and laterally out of alignment with the path of movement of the tractor 116 . The wheels 1808 are then moved back into alignment with the wheels of the tractor. Like the prior embodiment, the caboose rotates about the kingpin and does not remain aligned with the longitudinal axis of the trailer throughout the above sequence. To make this possible, the nose portion of the caboose may need to be removed from engagement with the members 404 a,b , such as by moving a movable plate, to which the members are attached, away from the nose portion.
[0130] In another embodiment, the caboose is motorized independently of the tractor. An engine is incorporated directly into the caboose to provide self-movement and power. In one configuration made possible by this embodiment, the platforms could engage simultaneously two cabooses with a TMA positioned on each caboose to provide crash attenuation at both ends of the trailer. One or both of the cabooses is motorized. This is particularly useful where the trailer may be on site for longer periods and needs only nominal movement from time-to-time, such as at gates, for spot inspection stations, or for security and/or military applications where unmanned and/or more protected movement is desired.
[0131] In other embodiments, the caboose is attached permanently to the platform. In this embodiment, different tractor/trailers, that are mirror images of one another, are used to handle roadside work areas at either side of a roadway.
[0132] The present invention, in various embodiments, includes components, methods, processes, systems and/or apparatus substantially as depicted and described herein, including various embodiments, sub combinations, and subsets thereof. Those of skill in the art will understand how to make and use the present invention after understanding the present disclosure. The present invention, in various embodiments, includes providing devices and processes in the absence of items not depicted and/or described herein or in various embodiments hereof, including in the absence of such items as may have been used in previous devices or processes, e.g., for improving performance, achieving ease and/or reducing cost of implementation.
[0133] The foregoing discussion of the invention has been presented for purposes of illustration and description. The foregoing is not intended to limit the invention to the form or forms disclosed herein. In the foregoing Detailed Description for example, various features of the invention are grouped together in one or more embodiments for the purpose of streamlining the disclosure. This method of disclosure is not to be interpreted as reflecting an intention that the claimed invention requires more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive aspects lie in less than all features of a single foregoing disclosed embodiment. Thus, the following claims are hereby incorporated into this Detailed Description, with each claim standing on its own as a separate preferred embodiment of the invention.
[0134] Moreover, though the description of the invention has included description of one or more embodiments and certain variations and modifications, other variations and modifications are within the scope of the invention, e.g., as may be within the skill and knowledge of those in the art, after understanding the present disclosure. It is intended to obtain rights which include alternative embodiments to the extent permitted, including alternate, interchangeable and/or equivalent structures, functions, ranges or steps to those claimed, whether or not such alternate, interchangeable and/or equivalent structures, functions, ranges or steps are disclosed herein, and without intending to publicly dedicate any patentable subject matter. | In one embodiment, a safety trailer has semi-tractor hitches at both ends and a safety wall that is fixed to one side of the trailer. That side, however, can be changed to the right or left side of the road, depending on the end to which the truck attaches. A caboose can be attached at the end of the trailer opposite the tractor to provide additional lighting and impact protection. Optionally, the trailer can be equipped with overhead protection, lighting, ventilation, onboard hydraulics, compressors, generators and other equipment, as well as related fuel, water, storage and restroom facilities and other amenities. | 4 |
TECHNICAL FIELD OF THE INVENTION
This invention relates to exhaust gas emission control for internal combustion engines, and more particularly to controlling nitrogen oxides using nitrogen oxide adsorbers.
BACKGROUND OF THE INVENTION
Today's conventional diesel engines produce nitrogen oxides (NO x ), which play a role in forming photochemical smog. Yet diesel engines are so durable, reliable, and efficient, it is important to keep them as viable options for transportation.
Increasingly strict regulations have prompted research for new ways of controlling the polluting emissions from diesel engines without compromising fuel economy. In the United States, Environmental Protection Agency rules require cleaner diesel fuel (lower sulfur content) and more stringent engine standards (reducing particulate matter and nitrogen oxide emissions).
Researchers have demonstrated that nitrogen oxide emissions can be reduced by exhaust recirculation in both gasoline and diesel engines. However, only a limited amount of exhaust can be recirculated without reducing power output and fuel economy. Recirculated soot particles may also cause wear in diesel engines. Other methods for NOx reduction that are being studied are fuel-water emulsion, selective catalytic reduction with ammonia or urea, lean NOx catalysts, and NOx adsorbers.
NOx adsorbers (NOx traps) are a promising development as results show that NOx adsorber systems are less constrained by operational temperatures than lean NOx catalysts. NOx traps adsorb and store NOx under lean conditions. A typical approach is to speed up the conversion of nitric oxide (NO) to nitrogen dioxide (NO 2 ) using an oxidation catalyst so that NO 2 can be readily stored as nitrate on alkaline earth oxides. A brief return to stoichiometric or rich operation for one or two seconds is enough to desorb the stored NOx and provide the conditions of a conventional three-way catalyst mounted downstream to destroy NOx.
One design for using NOx adsorber technology is referred to as a “dual leg” or “dual path” design. In these systems, the exhaust path splits into two paths, with a NOx adsorber on each new path. Typically, one path receives most of the exhaust flow while the other path is in regeneration mode. After regeneration, that path begins to receive most of the exhaust flow while the other path regenerates. The paths continually switch modes in this manner.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates a dual path NOx adsorber system in accordance with the invention.
FIG. 2 illustrates a method of controlling a dual path NOx adsorber system in accordance with the invention.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 illustrates a dual path NOx adsorber system 10 in accordance with the invention. Engine 11 is assumed to be a diesel internal combustion engine, but the invention could be modified for other types of engines that use NOx adsorption for treating exhaust.
Exhaust is exhausted from engine 11 into dual path NOx adsorber system 10 , which is described below. In the example of this description, system 10 is immediately downstream of engine 11 . An oxidation catalyst (OC) 12 and a carbon soot filter (CSF) 13 are downstream of the NOx adsorber system 10 .
In other embodiments of the invention, the arrangement of system 10 relative to any other exhaust treatment device(s) could be varied. Thus, oxidation catalyst 12 and/or carbon soot filter 13 could be upstream of system 10 rather than downstream, and other treatment devices could be placed upstream or downstream.
System 10 has two lean NOx traps (LNTs) 14 , one on each path of system 10 . NOx adsorber technology uses a three step process for the reduction of NOx. The first step is for the NO and excess O 2 in the exhaust gas to be chemically converted to NO2 over a platinum-based catalyst during lean engine operation. The second step is storing or adsorbing the NO2 as a nitrate on an site within a catalyst substrate. Before NO2 saturation is reached, the third step is to supply enough reductant (CO, HC, H2, etc) in the exhaust to maintain a rich operation long enough to chemically react the stored NO2 to produce nitrogen, water, and carbon dioxide. Various NOx adsorption devices could be used, with the common feature being NO2 saturation and the need for periodic regeneration (desorption).
Typically, each adsorber 14 has substantially equal adsorption capacity. As explained below, during engine operation, adsorbers 14 may be in either “adsorption mode” or “regeneration mode”. In adsorption mode, each adsorber 14 receives exhaust appropriate for its relative adsorption capacity, typically one-half.
In adsorption mode, approximately one-half of the exhaust from engine 11 is directed to a first path of system 10 and the other half to the second path. When an adsorber 14 nears NO2 saturation, it enters regeneration mode.
Various means may be used to determine when adsorbers 14 require regeneration (by being saturated or by having reached a predetermined NOx conversion efficiency). In the example of FIG. 1 , NOx sensor 19 a is placed upstream of adsorbers 14 (and upstream of valves 15 ) and NOx sensors 19 b are placed immediately downstream of adsorbers 14 . Sensors 19 a and 19 b sense the NOx content of the exhaust and deliver a signal to control unit 18 . Control unit 18 processes the sensor signals to determine NOx conversion efficiency. This parameter is used to determine when regeneration is required. Control unit 18 may be part of a more comprehensive engine control unit.
NOx sensors 19 a and 19 b allow NOx conversion efficiency (CE) to be calculated as follows:
CE= ((upstream NOx −downstream NOx )/upstream NOx )) (100)
This calculation is performed in control unit 18 , and can be used to maintain the NOx conversion efficiency at a predetermined rate, such as 95%. The desired efficiency determines the regeneration frequency. The adsorbers are regenerated prior to being saturated, so as to avoid NOx breakthrough.
Regeneration is accomplished by restricting the flow down the path being regenerated to approximately five percent or less of the total exhaust flow from engine 11 . During regeneration, the remainder of the flow is directed to the second path. Diverter valves 15 are used for this purpose.
During regeneration, the regenerating path receives supplemental diesel fuel injected into the exhaust stream upstream from adsorber 14 . One of the injectors 16 is used for this purpose. The fuel injection is sufficient so as to achieve an air-fuel ratio of 0.6<λ<0.8 for a period of time less than ten seconds. Other regeneration methods could be used, alternatively or in addition to supplemental fuel injection, such as intake throttling and/or exhaust gas recirculation (EGR).
At completion of the regeneration period for the first path, valves 15 are activated so as to again direct the exhaust in equal amounts to both paths of system 10 . Thus, both adsorbers 14 are again in adsorption mode. Shortly thereafter, the second path is regenerated using the same scheme as described above for regeneration of the first path. That is, the exhaust flow is reduced and supplemental fuel is injected. At completion of regeneration of the second path, the valves 15 are activated to once again direct the exhaust in equal amounts to both paths. System 10 remains in this state until the next regeneration cycle occurs.
FIG. 2 further illustrates the method of controlling system 10 . For purposes of example in FIG. 2 , it is assumed that adsorbers 14 are to be regenerated approximately on a cycle of less than 5 minutes. Normally, a lean-to-rich exhaust condition is 30/3, which means that that NOx adsorbers 14 run 3 seconds rich for every 30 seconds of lean operation.
As illustrated, in Step 21 , both paths are in adsorption mode for a period of less than 5 minutes. Each path receives an appropriate amount of exhaust, which is typically one-half the exhaust where adsorbers 14 are of the same capacity. Then, in Step 22 , a first path is placed in regeneration mode, receiving approximately 5% or less of the exhaust. The remainder of the exhaust is directed to the second path while the first path is in regeneration mode. As stated above, the regeneration mode is of brief duration, for example, 10 seconds. In Step 23 , both paths are again placed in adsorption mode, each receiving its fair share of exhaust. In the example of FIG. 2 , this second adsorption mode is very brief. In Step 24 , the second path is placed in regeneration mode, and receives approximately 5% or less of the exhaust while in that mode.
It should be understood that the durations of the adsorption and regeneration modes may vary and that various timing and sensing schemes could be used to control the duration of each mode. For example, experimentation may reveal that a particular frequency of regeneration is optimum. It is also conceivable that Step 23 could be omitted, such that the second path is regenerated immediately after the first path and such that the two paths are simultaneously in adsorption mode only during Step 21 .
The method described above can be implemented with a control unit 18 , which contains a processor and appropriate memory. Control unit 18 is programmed to generate appropriate control signals to diverter valves 15 and injectors 16 . It may receive signals from NOx sensors 19 a and 19 b to determine when regeneration is required, or as discussed below, may include timing means to determine when regeneration is to occur.
Alternatively, sensors 19 a and 19 b may determine the need for regeneration by sensing NOx “breakthrough” past adsorbers 14 . If regeneration fails to revive the adsorber 14 , a desulfurization process may be required. This occurs when sulfur from fuel or oil occupies the catalyst sites in the adsorber and denies them to NOx. Desulfurization may be accomplished thermally by heating the adsorber.
As a result of the above-described regeneration method both adsorbers 14 are in use during the adsorption period. They are adsorbing in unison, and regenerating successively for brief alternating periods. Both adsorbers are together in adsorption mode substantially longer than the time they are in regeneration mode. For example, if the total regeneration time for both adsorbers 14 was 5 seconds per cycle, they would be in adsorption mode and receiving equal amounts of exhaust for much longer time per cycle.
This increases the overall capacity of system 10 to adsorb NOx. In effect, the method reduces the space velocity of system 10 as compared to other dual path adsorber systems, where “space velocity” is defined as the maximum engine flow divided by the total NOx adsorber catalyst volume. The residence time for NOx adsorption is increased, and the overall NOx reduction is improved. Experimentation has been successful with an adsorber-to-engine-displacement ratio of 2.9:1.
System 10 provides satisfactory NOx reduction without the use of exhaust gas recirculation. Thus, the durability of modern diesel engines is not compromised by recirculated exhaust. In addition, the reduced cost of the precious metal required to construct the adsorbers makes the above-described system even more attractive.
Other Embodiments
Although the present invention has been described in detail, it should be understood that various changes, substitutions, and alterations can be made hereto without departing from the spirit and scope of the invention as defined by the appended claims. | A method of controlling a dual path NOx adsorber system. The amount of exhaust into the two paths of the system is controlled by a diverter valve at the beginning of each path. The valves are operated such that most of the time, the adsorbers are simultaneously in adsorption mode. The adsorbers alternate with each other to briefly enter a regeneration mode, during which they receive a very small amount of the exhaust flow and also receive supplemental fuel injection. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims priority to and benefit from, under 37 C.F.R. §1.119(e), U.S. Provisional Patent Application Ser. No. 62/081,114 filed on Nov. 18, 2014; U.S. Provisional Patent Application Ser. No. 62/120,606 filed on Feb. 25, 2015; and, U.S. Provisional Patent Application Ser. No. 62/250,657 filed on Nov. 4, 2015. All applications are hereby incorporated by reference.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not applicable
REFERENCE TO A “MICROFICHE APPENDIX”
Not applicable
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention pertains to the field of mine safety and more specifically the provision of safe havens in underground mines to provide safe refuge for miners unable to escape their work area immediately after a disaster due to toxic gases or a blocked escapeway.
2. General Background of the Invention
In many mining disasters in underground mines, many miners survive the initial disaster only to lose their lives due to an inability to escape from or isolates themselves from poisonous gases that build up in the mine in the wake of the disaster. For example, in 2006, there were three major mining disasters involving fire or explosion. In these events, 19 miners lost their lives despite surviving the initial disaster.
In the wake of these 2006 disasters, the MINER Act (Mine Improvement and New Emergency Response Act of 2006) was enacted. As part of the mandate of the MINER Act, NIOSH was charged with researching refuge alternatives to determine what alternatives would provide the best protection for miners following a disaster. The primary function of a refuge alternative is to provide a safe haven for miners unable to escape their work area immediately after a disaster due to toxic gases or a blocked escapeway. To be effective, a refuge alternative must, at a minimum, survive the initial disaster. In addition, it would be beneficial if the refuge alternative would protect the miners from any secondary explosions. This research considered both built-in-place and portable refuge chambers (i.e. safe havens).
The research concluded that built-in-place alternatives were highly preferable. Such alternatives provide a superior environment to miners using them for refuge, which can beneficial to the health of the miners following a disaster. Such built-in-place alternatives also provide the ability to deliver an unlimited supply of breathable air through a borehole or a protected compressed air line, examples of the latter being the Hubble® Breathable Air Units (Models HBA 75, HBA 100, and HBA 250) that have been approved by MSHA for such use.
In an April 2015 NIOSH report 1 focused on facilitating the use of built-in-place safe havens, the authors noted that there were approximately 30 built-in-place safe havens in use in underground coal mines in the U.S.; none of which were capable of being relocated as the working face is advanced. The ability to relocate the safe haven is, however, highly desirable to keep the safe haven within the preferred distance from the working face of the mine. But the benefits of a built-in-place safe haven are so great, a 2007 report to Congress in the wake of the MINER Act advised that, if a built-in-place safe haven is used, permitting extended distance from the working face should be considered despite the obvious additional risks this would pose to miners, especially injured miners, in getting to the safe haven before the air available through the miner's self-contained self-rescuer is exhausted. 1 NIOSH [2015]. Facilitating the use of built-in-place refuge alternatives in mines. By Trackemas J D, Thimons E D, Bauer E R, Sapko M J, Zipf R K, Schall J, Rubinstein E, Finfinger G L, Patts L D, LaBranche N. Pittsburgh, Pa.: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, DHHS (NIOSH) Publication No. 2015-114, RI 9698.
Thus, it is clear that there is need for an apparatus that can be used to create the equivalent of a built-in-place safe haven in an underground mine that is also capable of being relocated as the working face of the mine advance. The present invention addresses this need. Unlike the known examples discussed above, the present invention is an adjustable height wall that can be assembled outside the mine and transported to the desired safe haven location at a lower cost than constructing a permanent wall in place. Once transported to the desired location in the mine, the wall of the present invention can be installed to create the equivalent of a built-in-place safe haven. Moreover, as the working face advances, the wall of the present invention can be relocated within the underground mine to keep the safe haven within the preferred distance from the working face. Thus, the present invention provides the equivalent of a built-in-place safe haven with all of the attendant benefits at a lower cost without the need to consider allowing it to be located further from the working face.
SUMMARY OF THE INVENTION
A safe haven wall for use in defining a safe haven in an underground mine comprising a lower section and an upper section, wherein said upper section is slidingly engaged to the lower section.
BRIEF DESCRIPTION OF THE DRAWINGS
For a further understanding of the nature, objects, and advantages of the present invention, reference should be had to the following detailed description, read in conjunction with the attached figures, wherein like reference numerals denote like elements and wherein:
FIG. 1 —is a perspective view of an embodiment of the invention.
FIG. 2 —is a partially exploded perspective view of an embodiment of the invention.
FIG. 3 —is a partially exploded partial perspective view of an embodiment of the invention.
FIG. 4 —is a partially exploded partial perspective view of an embodiment of the invention.
FIG. 5 —is a perspective view of an embodiment of the invention.
FIG. 6 —is a partial perspective view of an embodiment of the invention.
FIG. 7 —is a partial perspective view of an embodiment of the invention.
FIG. 8 —is a perspective view of an embodiment of a base portion of the invention.
FIG. 9 —is a perspective view of an embodiment of a base portion of the invention.
FIG. 10 —is a perspective view of an embodiment of a base portion of the invention.
FIG. 11 —is a front view of an embodiment of a hatch portion of the invention.
FIG. 12 —is a cross-section view of the hatch portion of the invention from FIG. 11 .
DETAILED DESCRIPTION OF THE INVENTION
The present invention is safe haven wall 100 for use in underground mines to define an area within a mine in which miners and other personnel who are in the mine at the time of a catastrophic event such as an unplanned explosion or roof collapse can be safe when immediate egress is not possible. Safe haven wall 100 comprises lower section 200 and upper section 300 . Lower section 200 and upper section 300 preferably comprise separate fabrications that are brought together at the mine to facilitate the movement of safe haven wall 100 . One of the primary benefits of safe haven wall 100 is that it can be relocated within the mine after its initial installation or removed from the mine and installed in a different mine.
Lower section 200 comprises base plate 210 , vertical members 220 , angular base members 240 , sheathing panels 250 and opposing end portions 211 , 213 . Base plate 210 may be formed from steel C-channel, where central portion 212 of the C-shape is placed adjacent to the mine floor across the opening to the safe haven and opposing end portions 211 , 213 extend upwards. Defined in central portion 212 of base plate 210 are spaced apart apertures 214 to facilitate the bolting of base plate 210 to the mine floor across the opening to the safe haven or to base 120 if the additional height is required. The minimum spacing of apertures 214 is determined by the overall length and height of safe haven wall 100 . In any event, the spacing is selected to ensure safe haven wall 100 can withstand a static pressure of 15 pounds per square inch (“PSI”). In a particular non-limiting embodiment in which the length of safe haven wall 100 is from nineteen to twenty-one feet, it is preferable to provide and utilize at least 14 equally-spaced apertures 214 to secure lower section 200 to the mine floor. It is also advantageous to utilize additional apertures 214 near the end portions of lower section 200 .
In the illustrated embodiment, vertical members 220 are steel I-beams that extend upward from base plate 210 . Vertical members 220 are affixed such that outer surface 222 of vertical member 220 will be adjacent upright portion 216 of base plate 210 that faces outward (i.e. away from) the safe have when safe haven wall 100 is in place. When base plate 210 and vertical members 220 are steel, welding is one method that can be used to affix vertical members 220 to base plate 210 .
The spacing of vertical members 220 is selected based on the height of lower section 200 and the maximum overall height of safe haven wall 100 to ensure safe haven wall 100 can withstand a static pressure of 15 PSI. It is, however, preferable to space each pair of vertical members 220 to provide at least a 30-inch clear span to enable a stretcher to pass through the space between said pair of vertical members 220 . An exception to this spacing is for vertical members 220 at the opposing ends of lower section 200 . The height of vertical members 220 is less than the height of the mine ceiling at the desired construction location. In one embodiment, for use in a mine with a 51-inch ceiling, vertical members 220 are approximately 40 inches in height. Defined in the upper portion of vertical members 220 are apertures 224 that are parallel to safe haven wall 100 (where steel I-beams are used for vertical members 220 , apertures 224 are defined in the web of the I-beam).
Angular base members 240 are affixed to base plate 210 such that one angular base member 240 extends between each pair of vertical members 220 . In each case, upright portion 242 of angular base member 240 is adjacent to upright portion 216 of base plate 210 that faces outward (i.e. away from) the safe have when safe haven wall 100 is in place. Upright portion 242 of angular base member 240 has a height that is greater than upright portion 216 of base plate 210 . This configuration results in outer surfaces 244 of upright portions 242 of angular base members 240 cooperating with outer surfaces 222 of vertical members 220 to form a plane for affixing sheathing panels 250 . This also allows the edge portion of upright portion 216 of base plate 210 to function as a ledge upon which sheathing panels 250 can rest while it is being affixed to vertical members 220 and angular base members 240 .
In the illustrated embodiment, sheathing panels 250 are comprised of two different materials: steel (sheathing panels denoted as 250 s ) and polycarbonate (sheathing panels denoted as 250 pc ). Sheathing panels 250 for a single installation could, however, be all of single material, including steel or polycarbonate, provided said material is capable of being affixed to vertical members 220 and base members 240 and capable of withstanding a static pressure of 15 PSI. Sheathing panels 250 are preferably affixed to the outward facing sides of vertical members 220 and angular base members 240 . In the case of steel sheathing panels 250 s , said affixation is preferably accomplished through welding.
In the case of polycarbonate sheathing panels 250 pc , the panels may be affixed in a number of ways. One advantageous manner of attaching sheathing panels 250 pc is the use of double-sided tape 252 such as 3M VHB Tape, which has the added benefit of forming an airtight seal. Another manner of affixing sheathing panels 250 pc is with structural silicone (not shown) such as Tremco Spectrem 2, which also has the benefit of forming an airtight seal.
Instead of or as a supplement to the foregoing, sheathing panels 250 pc may be affixed to vertical members 220 and angular base members 240 using bolts 258 that extend through apertures 256 that are held in place using nuts 260 . Washers 262 are preferably between the head of bolt 258 and the outer surface of sheathing panel 250 pc to evenly distribute the pressure exerted by the head of bolt 258 . (Reference numbers 258 , 260 , and 262 , are respectively used herein to identify bolts, nuts, and washers generally. One of skill in the art will, however, recognize that specific bolts, nuts, and washers may be selected for the various uses of bolts, nuts, and washers in connection with safe haven wall 100 .)
Upper section 300 comprises ceiling plate 310 , mating members 320 , overlap plate 350 and opposing end portions 311 , 313 . Ceiling plate 310 may be formed from steel C-channel, where central portion 312 of the C-shape is placed adjacent to the mine ceiling across the opening to the safe haven and opposing end portions 311 , 313 extend downwards. Defined in central portion 312 of ceiling plate 310 are spaced apart apertures 314 to facilitate the bolting of ceiling plate 210 to the mine ceiling. Apertures 314 may be aligned with apertures 214 in base plate 210 . In any event, the spacing is selected to ensure safe haven wall 100 can withstand a static pressure of 15 PSI.
Mating members 320 are affixed to ceiling plate 310 and located to mate with vertical members 220 of lower section 200 . In the illustrated embodiment, mating members 320 are formed from steel tubing have a generally rectangular cross section. The width of mating members 320 is selected to enable mating members 320 to slide within the channel of the I-beams used for vertical members 220 . For outer vertical members 220 , only a single mating member 320 is provided. For other vertical members, a pair of mating members 320 is provided. Where a pair is provided, mating members 320 forming the pair are spaced apart to accept the I-beam web of vertical member 220 . Each mating member 320 is provided with slots 324 defined in the wall of the tubing adjacent to vertical member that generally align with apertures 224 defined in vertical members 220 .
Overlap plates 350 are then affixed to the downward extending portion of ceiling plate 310 that faces outward (i.e. away from) the safe haven when safe haven wall 100 is in place. In the illustrated embodiment, overlap plates 350 are formed of steel. In such a case, welding is the preferred method of affixing overlap plates 350 to ceiling plate 310 . In alternate embodiments, other types of fixation may be required. Defined in overlap plates 350 are slots 352 . Slots 352 are arranged to align with apertures 252 in sheathing panels 250 .
Lower section 200 and upper section 300 are mated together by aligning vertical members 220 and mating members 320 . Upper section 300 is allowed to slide down until vertical members 220 are supporting ceiling plate 310 , giving safe haven wall 100 a height that is less than the ceiling of the mine. Safe haven wall 100 is then transported to the location of the safe haven and placed across the opening to the safe haven. Jacks are then uses to elevate upper section 300 until ceiling plate 310 is adjacent to the ceiling of the mine. Base plate 210 and ceiling plate are then bolted to the mine floor and mine ceiling respectively using anchor bolts. Vertical members 220 and mating members are then bolted together using bolts 258 that pass through slots 324 in mating members 320 and apertures 214 in vertical members 220 that are aligned. Overlap plates 350 are then bolted to sheathing panels 250 utilizing bolts 258 that pass through slots 352 in overlap plates 350 and apertures 252 in sheathing panels 250 that are aligned. To form an airtight seal, expanding foam or pressurized grout bags or other MSHA approved sealant or other suitable fill material or a combination thereof may be used to address any unevenness in the mine floor or mine ceiling at the installation location. Alternatively, safe haven wall 100 may be placed on top of unfilled pressurized grout bags and unfilled pressurized grout bags are placed on top of safe haven wall 100 and between sliding panels 400 and 410 and the vertical walls of mine. Once upper section 300 is elevated into position adjacent to the mine ceiling, the pressurized grout bags are filled to create a seal around the perimeter of safe haven wall 100 . Once the pressurized grout bags have cured sufficiently, safe haven wall 100 is anchored to the mine floor and mine ceiling.
Opposing ends of the wall 100 are provided with sliding panels 400 and 410 that can be adjusted to alter the length of the wall. Sliding panels 400 and 410 are preferably formed from steel. Sliding panel 400 is affixed to sheathing panel 250 at each end of wall 100 using bolts 258 that pass through apertures 406 in sheathing panel 250 and horizontal slots 402 in sliding panel 400 . Sliding panel 402 is affixed to overlap plate 350 at each end of wall 100 using bolts 258 that pass through apertures 416 in overlap plate 350 and horizontal slots 412 in sliding panel 410 . Sliding panel 410 may also be provided with rod 414 welded to a bottom portion of sliding panel 410 to reduce the gap between the inner surface of sliding panel 410 and the outer surface sliding panel 400 , making it easier to form an airtight seal using expanding foam. The end portions of sliding panels 400 and 410 that will be adjacent to the mine walls may be provided with angle tabs 418 that can be used to bolt sliding panels 400 and 410 to the adjacent mine wall.
If needed, safe haven wall 100 may be configured to permit ingress and egress to a safe haven defined by safe haven wall 100 while still being able to create a positive pressure environment within the safe haven. In the illustrated embodiment aperture 251 is defined in sheathing panel 250 to permit such ingress and egress and hatch 500 is provided to form an airtight seal when it is in a closed position. In the illustrated embodiment, hatch 500 comprises door 510 , gasket 520 , hinges 530 , and latching mechanism 540 . Door 510 is a full overlay door that is larger than aperture 251 . Gasket 520 is affixed to the inner facing surface of door 510 and forms a circle that is of a larger diameter than aperture 251 . When door 510 is in its closed position, gasket 520 is received by circular groove 253 , which is defined in the outer surface of sheathing panel 250 and surrounds aperture 251 , to form an airtight seal. Steel plate 511 (show in FIGS. 11 and 12 ) may be used around all or a portion of the perimeter of door 510 to stiffen door 510 and prevent it from flexing when latched.
Hinges 530 are selected to enable door 510 to be parallel to sheathing panel 250 h when door 510 is in its closed position without causing undue binding on the hinge side of door 510 and without causing door 510 to be distorted when latched in its closed position. In the illustrated embodiment, each hinge 530 further comprises hinge bolt 532 and hinge strap 536 . Hinge bolt 532 is adapted on a first end to be bolted to vertical member 220 and that terminates at the opposing end in a hinge pin that extends perpendicularly to hinge bolt 532 . Hinge strap 536 further comprises a loop for receiving the hinge pin and is adapted to be bolted to door 510 .
Hatch 500 is also provided with a latching mechanism to hold hatch 500 in its closed, airtight position. In the illustrated embodiment, latching mechanism 540 comprises rotatable shaft 542 that extends through vertical member 220 . Affixed to the end of rotatable shaft 542 on the exterior side of safe haven wall 100 is latching member 544 . Latching member 544 is position to engage the outer surface of door 510 when door 510 is in its closed position and to latch door 510 in its closed position. Affixed to the end of rotatable shaft 542 on the interior side of safe haven wall 100 is a handle that allows latching mechanism 540 to be rotated from the interior of the safe haven. Door 510 may also be provided with a handle (not shown) extending inward toward the safe haven to assist with holding door 510 in its closed positions as it is being latched. While the illustrated embodiment includes only a single latching mechanism 540 , more than one may be included as deemed necessary to sufficiently latch door 510 in its closed positions. Where multiple latching mechanisms 540 are utilized, latching mechanism 542 may be adapted to extend through base plate 210 , overlap plate 350 , and/or ceiling plate 310 in similar fashion.
To facilitate movement of safe haven wall 100 within the mine, safe haven wall 100 may be provided with legs 450 . Each leg 450 extends from the inward facing surface of one of vertical members 220 . Each leg 450 comprises post portion 452 that, in the illustrated embodiment, is formed from rectangular steel tubing, but any material of suitable strength may be used. Foot 454 is affixed to the end of post portion 452 . Foot 454 is preferably formed to facilitate sliding wall 100 through the mine to the location of the safe haven. In the illustrated embodiment, this is accomplished by forming foot 454 from a rectangular piece of steel plate having a width approximately equal to the width of post portion 452 and bending up the end portions of the steel plate that extend toward opposing ends of wall 100 . Alternatively, foot 454 can have width greater than the width of post portion 452 with all edges bent upward to form a cup shape to facilitate sliding the wall laterally into and out of the entrance to the safe haven as well and longitudinally through the mine. To further facilitate the transport of safe haven wall 100 though the mine, each end of safe haven wall 100 may be provided with hitch 460 .
Safe haven wall 100 may also be provided with a number of ports 110 . In the illustrated embodiment, ports 110 are formed from circular pipe and sealed with threaded caps. Ports 110 enable cables, water lines, air supply lines, and the like to be extended through safe haven wall 100 and into the safe haven. One or more ports 100 can also be fitted with a one-way purge valve that will allow the atmosphere of the safe haven to be purged utilizing a continuous supply of fresh air from an external device such as the HUBBLE® breathable air unit. When a port 100 is opened to allow the insertion of cables, water lines, air supply lines, and the like, an airtight seal capable of withstanding a static pressure of 15 PSI can be achieved using expanding foam.
While the height of safe haven wall 100 can adapted for mines with different ceiling heights, safe haven wall 100 can also be mounted on base 120 if the ceiling height exceeds its maximum height. Base 120 can be formed as a rigid beam with sufficient resilience to withstand the weight of safe haven wall 100 . While base 120 is illustrated as a solid block, base 120 may be constructed from other types of beam steel such as I beams, H beams, or box beams, tubing, or solid members such that the overall wall height is capable of withstanding as static pressure of 15 PSI. Base 120 must be secured to the mine floor in such a manner to allow it to withstand a static pressure of 15 PSI. One way this may be accomplished is by providing the inward side of base 120 with a plurality of angle brackets 122 that may be bolted to the floor of the mine. Safe haven wall 100 is bolted to the upper surface of base 120 . As discussed above, it may be necessary to use expanding foam or pressurized grout bags or other suitable fill material or a combination thereof to form an airtight seal if the floor of the mine is not level and smooth. An alternative design of base 120 is shown in FIG. 9 . In this design, base 120 is formed from hollow structural steel (“HSS”) configured as rectangular hollow beam 130 . If the rectangular cross-section has a pair of sides that are longer, the longer sides are attached to safe haven wall 100 and to the mine floor. In this configuration, one of the pair of sides that will be upright when base 120 is installed may be provided with apertures 132 to facilitate the bolting of hollow beam 130 to the mine floor and to safe haven wall 100 . If additional height is required, an additional HSS beam 134 can be welded to the top of beam 130 as illustrated in FIG. 10 . In this case, one of the pair of sides of both beam 130 and beam 134 that will be upright when base 120 is installed may be provided with apertures 132 . In either case, or in the case of a solid beam, steel plate 136 may be welded to the bottom of beam 130 to provide an alternate means of bolting beam 130 to the mine floor. Steel plate 136 may also be provided with lip 138 to give base 120 a “sled-like” capability to facilitate movement of base 120 .
To install safe haven wall 100 , the first step is to determine the approximate measurements of the opening to be sealed. This will enable selection or fabrication of safe haven wall 100 that is best suited for the particular mine. It is generally advantageous to assemble lower section 200 to upper section 300 outside of the mine. Ceiling plate 310 and base plate 210 are predrilled for attaching safe haven wall 100 to the ceiling and floor (or base 120 ) respectively. To facilitate installation, a template with the hole patterns of ceiling plate 310 and base plate 210 can be used to enable the predrilling of the ceiling or floor of the mine. If predrilling is not done, the anchor locations can be drilled as part of the anchoring process once safe haven wall 100 is in place. Safe haven wall 100 is then transported to the installation location using hitch 460 . Once safe haven wall 100 is at the installation location, it is tilted into place on the floor of the mine or base 120 . If base 120 is used, it is first set in place across the opening to be sealed and anchored to the floor of the mine. Upper section 300 is then raised to be adjacent to the ceiling of the mine and anchored to the ceiling of the mine. Bottom wall 200 is attached to the floor of the mine or base 120 (this can be done simultaneously with anchoring upper section 300 to the ceiling of the mine). Vertical members 220 and mating members are bolted together using bolts 258 that pass through slots 324 in mating members 320 and apertures 214 in vertical members 220 that are aligned. Sliding panels 400 and 410 are then slid outward and bolted in place to engage the vertical wall portions of the mine adjacent to the ends of safe haven wall 100 . When safe haven wall 100 is mounted on base 120 , if base 120 is not the full width of the opening, it can be provided with separate sliding panels or sliding panel 400 can be extended downward the height of base 120 . As the wall is installed and after installation, safe haven wall 100 can be sealed to the mine floor, ceiling, and sidewalls using pressurized grout bags, expanding foam, and similar known sealing materials that are approved for use in a mine. If grout bags are used, they can be put into place between the safe haven wall and the mine floor, wall, or ceiling and filled once the safe haven wall has been bolted in place. Once safe haven wall 100 is set in place, at least one fresh air line is installed through one of ports 110 and affixed to a regulator. At least one relief valve is installed in another of ports 110 to enable a positive pressure to be maintained within the safe haven defined by safe haven wall 100 .
Attached hereto as Appendix 1 and incorporated by reference herein is a report prepared for submission to MSHA that further describes the invention. Attached hereto to as Appendix 2 and incorporated by reference herein is an installation manual with further details of the process for installing the safe haven wall in a mine.
It should be noted that this describes only the particular, illustrated embodiment. Those of skill in the art will recognize that other choices could be made for the various components of safe haven wall 100 without departing from the scope of the invention. For example, vertical members 220 could be formed from steel tubing and mating members 320 from a smaller cross-section tubing that would telescope in an out of vertical members 220 .
The foregoing described embodiments are exemplary in nature and are not intended to limit the scope of the invention. | A safe haven wall for use in defining a safe haven in an underground mine comprising a lower section and an upper section, wherein said upper section is slidingly engaged to the lower section. | 4 |
BACKGROUND OF THE INVENTION
Cell-fusion techniques have been devised for several eucaryotic cell systems to facilitate formation of hybrid cells. Genetic exchange mediated by cell fusion had not been demonstrated with procaryotic microorganisms until Shaeffer et al. and Fodor and Alfoldi devised techniques involving fusion of protoplasts and regeneration of cells of the procaryotic genus Bacillus, [P. Schaeffer et al., Proc. Nat. Acad. Sci. 73, 2151-2155 (1976) and K. Fodor and L. Alfoldi, Proc. Nat. Acad. Sci. 73, 2147-2150 (1976)]. Still more recently, it was discovered that protoplastfusion-induced genetic exchange, including genetic recombination, is possible within the economically important genus Streptomyces [Baltz and Godfrey, copending patent application titled METHOD OF FACILITATING GENETIC EXCHANGE IN STREPTOMYCES BY PROTOPLAST FUSION Ser. No. 812,097, filed this even date].
A crucial step in the process of protoplast-fusion-induced genetic exchange or genetic recombination is recovery of variable cells from the fused protoplasts. In the case of Bacillus, the fused protoplasts were reverted to viable cells under conditions that had been well worked out previously for single cells. In the case of the filamentous Streptomyces, however, very little was known about the process of forming protoplasts capable of reverting to viable cells. M. Okanishi, et al. [J. Gen. Microbiol. 80, 389-400 (1974)] reported that S. griseus and S. Venezuelae protoplasts could be formed from cells taken from a mid-exponential growth phase by treatment with lysozyme and lytic enzyme No. 2 in a hypertonic medium and that these protoplasts could regenerate viable cells efficiently. They also reported that cells from stationary phase did not form protoplasts well at all. In contrast to Okanishi's report, I have discovered that Streptomyces cells from the mid-exponential growth phase revert very poorly; but that cells from the transition growth phase, which follows the classical exponential phase but precedes the stationary growth phase, regenerate very efficiently. My discovery relates, therefore, to the optimum conditions for preparing Streptomyces protoplasts which are capable of efficiently resynthesizing cell walls and regenerating viable cells. My technique increases the probability of detecting specific genetic exchange between different Streptomyces strains by protoplast fusion. Genetic exchange is an important tool for increasing variability within species which produce economically and therapeutically important metabolites, such as antibiotics. Industrial applications of this tool include constructing strains which produce high levels of specific metabolites such as antibiotics, antitumor agents, enzymes and other microbial products having useful properties, and constructing hybrid species which produce novel metabolites with useful properties.
DETAILED DESCRIPTION
This invention relates to a method of obtaining Streptomyces protoplasts which are capable of regenerating viable cells. The method involves growing Streptomyces cells to a particular physiological state and then forming protoplasts. The particular physiological state relates to a segment of the growth phase in which I have discovered that 1) the Streptomyces cells have the ability to form protoplasts efficiently and 2) the protoplasts formed have the ability to regenerate viable cells efficiently. This particular state, the most competent state, is the transition phase between the exponential and stationary phases.
The most competent state can be determined by monitoring the Streptomyces growth cycle. The cycle can be monitored by any one of a number of well known techniques. A convenient method is by turbidometric assay in a complex medium containing glycine. Using the turbidometric assay, the growth phases can be defined by measuring changes in optical density (OD). A suitable turbidometric measurement, such as absorbancy at 600 nm (A600), can be used to measure changes in OD.
In general, Streptomyces species undergo fairly rapid exponential growth with cell-doubling times ranging from about 1.5 hours to several hours at low cell density (A600) less than about 1.5) in soluble complex media. As cell growth reaches A600 readings of from about 1.5 to 4.0, cells enter a transition phase which precedes the stationary growth phase. The transition phase may last from 2 to 24 hours, and cell mass may increase by about 50% to 6-fold during this growth phase, depending on the species in question.
During the course of growth through these various phases, physiological changes take place which influence dramatically the ability to form protoplasts which are capable of reverting to viable cells. Protoplasts are formed typically by treatment of mycelial cells with lysozyme in a hypertonic medium.
I have found that cells from the early exponential growth phase (i.e., A600 of from about 0.5 to about 0.2, or even up to 0.4 with some Streptomyces) do not form protoplasts well. With S. fradiae, however, after the early exponential growth phase, there exists a transient period during which the cells can form protoplasts which will revert to viable cells: e.g., S. fradiae cells at A600 of about 0.4 can be converted to protoplasts, and the protoplasts will revert to viable cells fairly efficiently. This competency to regenerate cells, however, is rapidly lost as cells enter the mid-exponential growth phase.
In the mid-exponential growth phase (i.e., A600 of from about 0.7 to about 1.4), the Streptomyces cells will form protoplasts, but the protoplasts do not revert efficiently to viable cells. As cells enter the late exponential growth phase, however, they begin to regain the ability to form protoplasts which regenerate cells efficiently; and as they grow into the transition phase (an A600 of from about 2.0 to about 8.5) they become highly competent to form protoplasts which regenerate cells efficiently. Competency to regenerate then declines dramatically as cells enter the stationary growth phase.
A similar pattern is seen with S. griseofuscus and S. auerofaciens except that the transition phase preceding the stationary phase is much shorter.
My methods consists, therefore, of growing Streptomyces cells to the most competent state (the transition phase between the exponential and stationary phases), forming protoplasts, and allowing the protoplasts to revert to viable cells by plating on a suitable medium. My method, which facilitates efficient regeneration of cells from protoplasts, clearly enhances the probability of detecting genetic exchange, including genetic recombination, within the genus Streptomyces (see examples 4 and 5).
My method is intended to apply to many Streptomyces species. As discussed in further detail in Examples 1-3, my method has been demonstrated in Streptomyces fradiae, Streptomyces griseofusus and Streptomyces aureofaciens.
One streptomycete which has thus far failed to revert under these conditions is Streptomyces cinnamonensis, a strain which has been observed to produce potent autolytic activity after growth in complex medium supplemented with glycine.
Streptomyces species for which my method is preferred are those which produce antibiotics. Especially preferred Streptomyces species are those which produce aminoglycoside antibiotics, macrolide antibiotics, betalactam antibiotics, polyether antibiotics, or glycopeptide antibiotics.
Streptomyces species which are known to produce aminoglycoside antibiotics include, for example: S. kanamyceticus, S. chrestomyceticus, S. griseoflavus, S. microsporeus, S. ribosidificus, S. flavopersicus, S. spectabilis, S. rimosus forma paromomycinus, S. fradiae var. italicus, S. bluensis var. bluensis, S. catenulae, S. olivoreticuli var. cellulophilus, S. tenebrarius, S. lavendulae, S. albogriseolus, S. albus var. metamycinus, S. hydroscopicus var. sagamiensis, S. bikiniensis, S. griseus, S. erythrochromogenes var. narutoensis, S. poolensis, S. galbus, S. rameus, S. olivaceus, S. mashuensis, S. hygroscopicus var. limoneus, S. rimofaciens, S. hygroscopicus forma glebosus, S. fradiae, S. eurocidicus, S. aquacanus, S. crystallinus, S. noboritoensis, S. hygroscopicus, S. atrofaciens, S. kasugaspinus, S. kasugaensis, S. netropsis, S. lividus, S. hafunensis, and S. canus.
Streptomyces species which are known to produce macrolide antibiotics include, for example: S. caelestis, S. platensis, S. rochei var. volubilis, S. venezuelae, S. griseofuscus, S. narbonensis, S. fungicidicus, S. griseofaciens, S. roseocitreus, S. bruneogriseus, S. roseochromogenes, S. cinerochromogenes, S. albus, S. felleus, S. rochei, S. violaceoniger, S. griseus, S. maizeus, S. albus var. coilmyceticus, S. mycarofaciens, S. hygroscopicus, S. griseospiralis, S. lavendulae, S. rimosus, S. deltae, S. fungicidicus var. espinomyceticus, S. furdicidicus, S. ambofaciens, S. eurocidicus, S. griseolus, S. flavochromogenes, S. fimbriatus, S. fasciculus, S. erythreus, S. antibioticus, S. olivochromogenes, S. spinichromogenes var. suragaenosis, S. kitasatoensis, S. narbonensis var. josamyceticus, S. albogriseolus, S. bikiniensis, S. cirratus, S. djakartensis, S. eurythermus, S. fradiae, S. goshikiensis, S. griseoflavus, S. halstedii, S. tendae, S. macrosporeus, S. thermotolerans, and S . albireticuli.
Streptomyces species which are known to produce beta-lactam antibiotics include, for example: S. lipmanii, S. clavuligerus, S. lactamdurans, S. griseus, S. hygroscopicus, S. wadayamensis, S. chartreusis, S. heteromorphus, S. panayensis, S. cinnamonensis, S. fimbriatus, S. halstedii, S. rochei, S. viridochromogenes, S. cattleya, S. olivaceus, S. flavovirens, S. flavus, S. fulvoviridis, S. argenteolus, and S. sioyaensis.
Streptomyces species which are known to produce polyether antibiotics include, for example; S. albus, S. hygroscopicus, S. griseus, S. conglobatus, S. eurocidicus var. asterocidicus, S. lasaliensis, S. ribosidificus, S. cacaoi var. asoensis, S. cinnamonensis, S. aureofaciens, S. gallinarius, S. longwoodensis, S. flaveolus, S. mutabilis, and S. violaceoniger.
Streptomyces species which are known to produce glycopeptide antibiotics include, for example: S. orientalis, S. haranomachiensis, S. candidus, and S. eburosporus.
In order to illustrate more fully the operation of this invention, the following specific examples are provided.
EXAMPLE 1
Streptomyces fradiae was grown in trypticase soy broth (TSB) containing 0.4% glycine for 6 to 10 cell doublings. (Glycine at 0.4% increases the cell-doubling time during exponential growth from about 1.6 hours to 2.7 hours; higher concentrations are much more inhibitory). Specific growth phases were determined by optical density (OD) readings at an absorbancy of 600 nm (A600 on a Baush and Lomb spectrophotometer). Samples were removed from specific growth phases; cells were homogenized and washed two times by centrifugation, resuspending in medium P [M. Okanishi, et al., J. Gen. Microbiol. 80, 389-400 (1974)]. The washed cells were treated with lysozyme (1-2 mg/ml) in medium P for 1 to 2 hours at 34° C. The resulting protoplasts were washed 2 to 3 times by centrifugation, resuspending in medium P; the washed protoplasts were diluted in medium P and plated on R 2 medium (M. Okanishi et al., supra) which was modified in that it contained asparagine instead of proline as a nitrogen source. Regenerated cells which formed colonies were counted after 9 to 12 days incubation at 34° C. About one-half of the regenerated cells produced visible colonies in about 5 to 7 days on R 2 medium. Background counts (hypotonic conditions in Table 1) were determined either by diluting protoplasts in distilled water before plating on hypertonic medium (R2), or by diluting in hypertonic buffer (P) and then plating on a hypotonic medium containing 0.8% nutrient broth plus 4 mM Ca(NO 3 ) 2 . A summary of results from four experiments is given in Table 1. Cells from early exponential phase (i.e., cell-doubling time=2.7 hr; see Expt. No. 1) were not converted to protoplasts efficiently at all. Even after 16 hours incubation at 34° C., only a fraction had been converted to protoplasts. At an A600 of 0.46, cells were converted to protoplasts in 1 to 2 hours, and these protoplasts regenerated viable cells fairly efficiently. This "competent state" is rapidly lost as cells enter the mid-to-late exponential growth phase (A600 reading of 0.7 to 1.4). As cells enter the transition phase between the exponential and stationary growth phases at an A600 of about 1.4, they continue to grow, but at a much slower rate (i.e., cell-doubling time of about 11.5 hours), and begin to regain a high degree of competency to regenerate viable cells from protoplasts. The highest values, 8.6×10 7 colony-forming units (cfu)/OD, represent about 40% of maximum viability. As the cells enter stationary phase at about A600>8.5, they rapidly lose the ability to regenerate viable cells from protoplasts. The frequency of regenerated cells/OD from protoplasts formed during the most competent state (A600 of 2 to 4) is at least 30-fold and 300-fold higher than from protoplasts formed during the mid-to-late exponential and stationary phases, respectively.
Table 1__________________________________________________________________________ Colony-Forming Units/OD Cells*Expt. Cell Growth Protoplast Hypertonic HypotonicNo. OD Phase Formation Conditions Conditions__________________________________________________________________________1 0.16 Exponential Very poor ND** ND1 0.18 " Very poor ND ND1 0.30 " Very poor ND ND1 0.32 " Very poor ND ND1 0.38 " Very poor ND ND2 0.46 " Good 5 × 10.sup.7 <1.1 × 10.sup.32 0.72 " Good 6.8 × 10.sup.6 <6.4 × 10.sup.22 1.46 Late Good 2.7 × 10.sup.6 <3.4 × 10.sup.2 exponential3 1.4 " Very good 4.5 × 10.sup.7 2.1 × 10.sup.23 2.2 Transition Very good 8.6 × 10.sup.7 3.2 × 10.sup.13 3.7 " Very good 8.6 × 10.sup.7 6.8 × 10.sup.13 8.5 " Very good 6.5 × 10.sup.7 8.7 × 10.sup.14 9.0 Stationary Very good 2.5 × 10.sup.5 4.7 × 10.sup.3__________________________________________________________________________ *OD cells determined before protoplast **not determined
EXAMPLE 2
S. griseofuscus was grown in TSB containing 0.8% glycine, using the procedure of Example 1. Protoplasts were formed and plated as in Example 1, except that colonies were counted after 7 days. As seen with S. fradiae in Example 1, S. griseofuscus cells taken from the transition phase (A600 of about 3.5 to 5.0) form protoplasts and regenerate viable cells most efficiently (Table 2). The highest efficiency, 1.1×10 8 cuf/OD, represents nearly 100% regeneration of potential viable cells. Again, cells in the early exponential growth phase did not form protoplasts well, and protoplasts from the stationary phase yielded no detectable revertants (i.e., <5.8×10 3 cfu/OD). The efficiency of regenerating stationary-phase protoplasts is thus >10 4 -fold lower than the efficiency of regenerating transition-phase cells.
Table 2__________________________________________________________________________ Colony-Forming Units/OD Cells*Expt. Cell Growth Protoplast Hypertonic HypotonicNo. OD Phase Formation Conditions Conditions__________________________________________________________________________1 .16 Exponential Very poor ND** ND1 .23 " Very poor ND ND1 .35 " Very poor ND ND1 .42 " Very poor ND ND1 .54 " Very poor ND ND2 1.14 Late Good 2.2 × 10.sup.7 <4.4 × 10.sup.2 exponential2 2.4 " Good 4.7 × 10.sup.7 <2.1 × 10.sup.22 3.81 transition Good 9.1 × 10.sup.7 <1.3 × 10.sup.23 4.8 " Good 1.1 × 10.sup.8 <5. × 10.sup.23 4.3 stationary*** Good <5.8 × 10.sup.3 <5. × 10.sup.2__________________________________________________________________________ *OD cells determined before protoplast **not determined ***10 hrs beyond transition phase
EXAMPLE 3
S. aureofaciens was grown in TSB containing 0.4% glycine; protoplasts were formed and plated, using the procedure of Example 1 except that colonies were counted after 8 days incubation at 34° C. Again, as seen with S. fradiae in Example 1 and S. griseofuscus in Example 2, cells from the transition phase (A600 of about 2.0 in this case) form protoplasts which regenerate more efficiently than cells from the late exponential growth phase. As shown in Table 3, efficiency of regeneration at A600=2.4 was about 10 times greater than efficiency of regeneration at A600=0.6.
Table 3__________________________________________________________________________ Colony-Forming Units/OD Cells*Expt. Cell Growth Protoplast Hypertonic HypotonicNo. OD Phase Formation Conditions Conditions__________________________________________________________________________1 0.6 Exponential Good 3.5 × 10.sup.5 <8.3 × 10.sup.21 1.24 Late Good 4.6 × 10.sup.5 4.0 × 10.sup.2 exponential1 2.4 Transition Good 3.4 × 10.sup.6 2.1 × 10.sup.2__________________________________________________________________________ *OD cells determined before protoplast formation
EXAMPLE 4
Streptomyces fradiae auxotrophic mutants were used. At least one parent strain contained two auxotrophic markers and a spectinomycin resistance (spc) marker. Each of the genetically-marked S. fradiae strains was grown in TSB containing 0.4% glycine. When growth reached an A600 of about 1.5 to 5, the mycelia were washed twice by centrifugation and were resuspended in medium P (M. Okanishi, et al., supra). Lysozyme (1 to 2 mg/ml) was added to the suspension. The suspended mycelial cells were incubated for 0.5 to 2 hours at 30° or 34° C. The resulting protoplasts were mixed (0.5 ml of each parent suspension). The mixture was washed several times by centrifugation, resuspending in medium P and finally resuspending in 0.1 ml of medium P. A solution of 40% polyethylene glycol (PEG) 6000 in medium P (0.9 ml) was added to the final suspension to induce cell-membrane fusion. Protoplast fusion was confirmed by phase-contrast microscopy. The fused protoplasts were immediately diluted into one of the following media: medium P containing 40% PEG, medium P, or distilled water. The dilutions were plated on medium R2 (Okanishi, et al., supra) to allow detection of recombination and regeneration of prototrophic recombinants. The R2 medium used contained asparagine instead of proline as nitrogen source. Recombinants were counted after 10 to 24 days incubation at 34° C. In many of the crosses the prototrophic recombinants were further tested for the presence of an unselected marker (spectinomycin resistance) to eliminate single mutant reversion artifacts. Additional controls were run to confirm recombination. Total recombinants are based on original volumes of mixed protoplasts which generally contained from about 10 8 to about 10 9 protoplasts/ml, as determined by direct counting in a hemocytometer.
A summary of several genetic crosses by protoplast fusion is given in Table 4.
Table 4__________________________________________________________________________ Prototrophic SpectinomycinParental Markers ∇ PEG Dilution Recombinants, or ResistantCondition Parent 1 Parent 2 Treatment Medium Revertants/ml .increment. Prototrophs__________________________________________________________________________1 metA arg spc metB + P + PEG 2.4 × 10.sup.4 6/72 metA arg spc metB - P 6.6 × 10.sup.3 8/83 metA arg spc metB - H.sub.2 O 7.0 × 10.sup.1 11/114 metA arg spc -- + P + PEG <10.sup.1 0/05 metA arg spc -- - P <10.sup.1 0/06 metA arg spc -- - H.sub.2 O <10.sup.1 0/07 -- metB + P + PEG 2 × 10.sup.1 0/38 -- metB - P 2 × 10.sup.1 0/69 -- metB - H.sub.2 O 2 × 10.sup.1 0/810 metA arg spc cysD + P 1.1 × 10.sup.5 ND*11 -- cysD + P <10.sup.1 ND12 metA arg spc -- + P <10.sup.1 ND__________________________________________________________________________ *Not determined. .increment.Determined on R2 medium. ∇Marker designations are those of Hopwood, et al. [Bact. Rev. 37 371-405 (1973)]. The metA, arg and metB markers are auxotrophic. The spc marker designates resistance to 50 μg/ml spectinomycin.
A lower, but significant, level of recombination was obtained by centrifuging the protoplasts and resuspending in medium P without PEG. This level of protoplast fusion is presumably due to the presence of Ca ++ in the buffer. Dilution of the protoplasts into distilled water reduced the number of recombinants by 100-fold. Virtually all of the genetic recombinants tested contained the spc marker from the strain carrying the metA arg markers, ruling out the possibility that reversion of the metB strain might account for the data. The doubly marked auxotrophic strain has never been shown to revert to prototrophy, thus eliminating reversion of this strain as an explanation of the results. The other controls in Table 4 give additional evidence that recombination does indeed take place after protoplast fusion. Upon recloning, all putative recombinants were shown to be stable. The S. fradiae strain used is one which produces the antibiotic tylosin. Many genetic recombinants of this S. fradiae strain were shown to be tylosin producers.
EXAMPLE 5
Streptomyces griseofuscus was used in these genetic crosses. The procedures were the same as those used in Example 4 except that: (1) the TSB was supplemented with 0.8% glycine and (2) recombinant colonies were counted after 7 days incubation at 34° C. Results are summarized in Table 5. In all six conditions protoplasts were treated with PEG, diluted in medium P and plated on medium R2. In all cases, the frequency of genetic recombinants was from 10 3 to 10 4 -fold higher than background prototrophic revertants.
Table 5______________________________________ Prototrophic Parental Markers Recombinants orCondition Parent 1 Parent 2 Revertants/ml______________________________________1 met arg 3.1 × 10.sup.42 met trp 4.8 × 10.sup.33 arg trp 4.2 × 10.sup.44 met -- <10.sup.15 arg -- 1.0 × 10.sup.16 trp -- <10.sup.1______________________________________ | A method of obtaining Streptomyces protoplasts which are able to regenerate viable cells with high efficiency is disclosed. The method involves growing Streptomyces cells to a particular physiological state, the transition phase between the exponential and stationary growth phases, and then forming protoplasts. The physiological state of the cells at the time of protoplast formation is crucial for efficient cell regeneration. Protoplasts obtained by this method enhance the use of protoplast-fusion techniques to effect genetic exchange within the genus Streptomyces, thereby facilitating the construction of hybrid or recombinant Streptomyces strains with useful properties. | 2 |
BACKGROUND OF THE INVENTION
[0001] Actuators in tubular systems, such as the downhole completion industry, employ a variety of motive devices. Electrical motors, solenoids, shape memory alloys and hydraulic systems, are a few of the motive devices successfully employed. Each motive device has specific advantages as well as drawbacks and each finds applications to which they are well suited. A wide variety of applications necessitate a wide variety of motive devices thereby assuring that operators of tubular systems remain receptive to new actuators employing new motive devices.
BRIEF DESCRIPTION OF THE INVENTION
[0002] Disclosed herein is an actuator that includes a tubular configured to longitudinally expand in response to radial expansion of at least a portion of the tubular.
[0003] Further disclosed herein is a tubular actuator that includes a sleeve and a tubular in operable communication with the sleeve configured to longitudinally expand in response to radial expansion thereof. A first portion of the tubular is longitudinally fixed to the sleeve so that a second portion of the tubular moves in relation to the sleeve in response to the longitudinal expansion of the tubular.
BRIEF DESCRIPTION OF THE DRAWINGS
[0004] The following descriptions should not be considered limiting in any way. With reference to the accompanying drawings, like elements are numbered alike:
[0005] FIG. 1 depicts a side view of an actuator disclosed herein in a nonactuated configuration;
[0006] FIG. 2 depicts a side view of the actuator of FIG. 1 shown in an actuated configuration;
[0007] FIG. 3 depicts a perspective view of the actuator of FIG. 1 ;
[0008] FIG. 4 depicts a perspective view of the actuator of FIG. 2 ;
[0009] FIG. 5 depicts a partial cross sectional view of an alternate embodiment of an actuator disclosed herein in a nonactuated configuration;
[0010] FIG. 6 depicts a partial cross sectional view of the actuator of FIG. 5 shown in an actuated configuration;
[0011] FIG. 7 depicts a partial cross sectional view of another alternate embodiment of an actuator disclose herein; and
[0012] FIG. 8 depicts a perspective view of a tubular actuator disclosed herein;
DETAILED DESCRIPTION OF THE INVENTION
[0013] A detailed description of one or more embodiments of the disclosed apparatus and method are presented herein by way of exemplification and not limitation with reference to the Figures.
[0014] Referring to FIGS. 1-4 , an embodiment of an actuator disclosed herein is illustrated at 10 . The actuator 10 includes, a tubular 14 with a discontinuous wall 18 having a plurality of serpentine or sinuous members 22 orientated substantially perimetrically about the tubular 14 . The serpentine members 22 have longitudinal amplitudes with a plurality of bars 26 connected thereto. Pairs of the bars 26 that are perimetrically adjacent to one another have opposingly directed ends 30 , 34 connected to a same one of the serpentine members 22 . For example, the leftward end 30 , as illustrated herein, of one of the bars 26 is connected to a same one of the serpentine members 22 as the rightward end 34 of the perimetrically adjacent bar 26 such that the ends 30 , 34 longitudinally overlap one another. The amount of overlap in this embodiment is by a dimension 38 . The decrease in dimension 38 in response to radial expansion of the actuator 10 is due to a decrease in amplitude of the serpentine member 22 . This decrease of overlap puts the bars 26 in compression that causes a longitudinal growth of the actuator 10 . This characteristic, longitudinal growth in response to radial growth is known as auxetic and is associated with the actuator 10 having a negative Poisson's ratio.
[0015] Straight portions 42 of the serpentine members 22 in this embodiment intersect the bars 26 at angles 46 . The angles 46 increase as the amplitude of the serpentine members 22 decreases thereby approaching 90 degrees. As the angles 46 increase, during actuation, the bars 26 transmit compressive loads. These compressive loads cause adjacent serpentine members 22 to move longitudinally away from one another. Making the tubular 14 of a strong material, such as metal, for example, facilitates efficient transmission of the compressive forces through the bars 26 .
[0016] Referring to FIGS. 5 and 6 , an alternate embodiment of an actuator disclosed herein is illustrated at 110 . Unlike the tubular 14 of the actuator 10 , a tubular 114 of the actuator 110 has continuous walls. As such a wall 118 of the tubular 114 provides fluidic isolation between an inside 124 and an outside 128 of the tubular 118 . A wall 132 of the tubular 114 has a serpentine shape extending in a longitudinal orientation with amplitude 136 in a radial direction. When the actuator 110 is radially expanded inner points 140 of the tubular 114 are moved radially outwardly thereby putting portions 146 of the tubular 114 into compression which causes longitudinally adjacent inner points 140 , separated by dimension 150 , to move longitudinally away from one another resulting in longitudinal expansion of the actuator 110 as the dimension 150 increases in response to the radial expansion thereof.
[0017] Referring to FIG. 7 , in an alternate embodiment of an actuator 210 disclosed herein, a tubular 214 has a serpentine shape with curved walls 218 as opposed to the straight walls 118 of the actuator 110 . Otherwise the actuator 210 is similar to the actuator 110 and functions substantially in the same manner
[0018] Referring to FIG. 8 , a tubular actuator 310 disclosed herein is illustrated in a perspective view. The tubular actuator 310 includes a sleeve 316 with the tubular 114 , positioned radially outwardly of the sleeve 316 . A first portion 324 of the tubular 114 is fixedly attached to the sleeve 316 near a first end 328 thereof while a second portion 332 of the tubular 114 near a second end 336 thereof is slidably engaged about the sleeve 316 . Both the tubular 114 and the sleeve 316 are radially expandable by operations such as swaging or pressurizing a fluid contained therewithin, for example. The sleeve 316 having a simply cylindrical shape has a positive Poisson's ratio and as such longitudinally contracts upon being radially expanded. In contrast, the tubular 114 has a negative Poisson's ratio, as discussed above and longitudinally expands upon being radially expanded. Assuming the first portion 324 of the tubular 114 and the sleeve 316 attached thereto are stationary, then the tubular actuator 310 will cause an actuatable movement of a portion 340 of the sleeve 316 relative to the second portion 332 of the tubular 114 upon radial expansion of both the sleeve 316 and the tubular 114 . This relative motion is generated by movement of the portion 340 of the sleeve 316 toward the first portion 324 while the second portion 332 moves away from the first portion 324 . A tool (not shown), by being connected to both the second portion 332 and the portion 340 of the sleeve 316 , can be actuated through radial expansion of the tubular actuator 310 . It should be noted that although this embodiment discloses the sleeve 316 having a positive Poisson's ratio, other embodiments are contemplated that have non-positive Poisson's ratios. In fact, as long as the Poisson's ratios of the sleeve 316 and the tubular 114 are not the same the tubular actuator 310 will provide relative movement between the portion 340 and the second portion 332 enabling actuation thereby.
[0019] Embodiments of the actuators 10 , 110 , 210 and the tubular actuator 310 disclosed herein can be used in various industries. In the downhole completion industry, for example, the actuators 10 , 110 , 210 , 310 could be used to actuate the following tools; a packer, a centralizer, a backup, an anchor, a valve and a crusher (none shown).
[0020] While the invention has been described with reference to an exemplary embodiment or embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the claims. | An actuator includes a tubular configured to longitudinally expand in response to radial expansion of at least a portion of the tubular. | 4 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] The present application is a continuation application U.S. application Ser. No. 09/674,496 filed Jan. 11, 2001, pending, which is a 371 application of PCT/FR99/01085 filed May 7, 1999. The application also claims the benefit of FR 98/05877 filed May 11, 1998.
FIELD OF THE INVENTION
[0002] The present invention relates to insecticidal proteins and to the use thereof for protecting plants, and in particular cereals, their seeds and products derived from them, against insect pests.
BACKGROUND
[0003] Insects which are pests for cereal seeds are to be found in various families, in particular among Coleoptera, Lepidoptera and Homoptera. Among Coleoptera, mention will be made in particular of grain weevils (Sitophilus oryzae, Sitophilus zeamais, Sitophilus granarius), and of Tenebrio spp, Rhyzopertha dominica, Trogoderma spp. and Triboiiurn coNfusum. Among Lepidoptera, mention will be made in particular of Sitotroga cereaieiia and Ephestia kuehnieiia.
[0004] Pests for cereal seeds are among the main enemies of the crops which they attack in the field (at least in hot regions), and especially in storage silos; they may also attack transformed products which are derived from cereals (for example, flours, semolinas, etc). These insects cause very significant damage and, each year, cause the destruction of a large portion(which can come close to 25%) of the world harvest of cereals harvested each year.
[0005] In order to combat these insects, various methods have been recommended. The use of insecticides (LINDANE®, then MALATHION® and ethylene bromide) is currently being challenged because of the problems posed by the presence of residues of these products in food. In addition, resistance to these products has appeared in many target insects, which makes their use less and less effective. In order to replace these insecticides or limit their use, various methods have been proposed [for review, cf for example F. H. ARTHUR, J. Stored Prod. Res, 32, pp. 293-302, (1996)]. The methods which are currently the most developed are physical methods, such as the cooling of silos or storage under 002 or under nitrogen; these methods are, however, expensive and their use, which requires great technological sophistication, is delicate; they are therefore not applicable everywhere.
[0006] Another type of approach, which is the subject of much research, consists in producing transgenic plants expressing one or more gene(s) which confer(s) on them resistance against insect attack. However, this approach requires the availability of suitable genes, which must also be acceptable both for the environment and by consumers.
[0007] Most insects exhibit more or less strict food specificity; it is in this way that cereal seeds are attacked by grain weevils (Sitophilus oryzae, Sitophilus zeamais, Sitophiius granarius) which do not attack legume seeds; conversely, other pests, such as bruchid beetles, attack legumes but not cereals.
[0008] Previous studies by the inventors' team [DELOBEL and GRENIER, J. Stored Prod, Res, 29, pp. 7-14, (1993)] have shown that the three species of Sitophilus mentioned above can develop on chestnuts or acorns, but that, conversely, they die rapidly on split peas, this mortality being consecutive to the consumption of the peas by these weevils.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 shows a calibration curve calculated from each concentration of pea meal the time for 50% lethality (LT50) for the sensitive strain S.
[0010] FIG. 2 shows the cumulative mortality for adults of the sensitive strain S of Sitophilus oryzae, on pea (⋄) and on wheat (□) as a function of the feeding time in days.
[0011] FIG. 3 shows the mortality at 6 days of Sitophilus oryzae for balls containing various concentrations of pea meal; the resistant strain (R) and sensitive strain (S) are compared.
[0012] FIG. 4 shows the cumulative mortality of the Sitophilus oryzae weevils, resistant strain R or sensitive strain S measured after 5 ( 4 A), 7 ( 4 B), 14 ( 4 C) and 20 ( 4 D) days of feeding on cowpea (Vigna unguiculata) white (1) and red (2) variety bambora groundnut, lentil, French bean, mung bean, adzuki bean, broad bean, chickpea, and lupin.
[0013] FIG. 5 shows a chromatogram of the anion exchange chromatography described in Example 2.
[0014] FIG. 6 shows a chromatogram of the semipreparative reverse phase HPLC chromatography described in Example 2.
[0015] FIG. 7 shows the alignment of the sequence of one of the TP protein (SEQ ID NO:6), with those of pea PA1b protein (SEQ ID NO:7) and soybean leginsulin (SEQ ID NO:8).
[0016] FIG. 8 shows the results of testing the toxicity of the TP protein for the flour moth Ephestia kuehniellea (Lepidoptera) and for the aphid (Acyrthosiphon pisum).
[0017] FIG. 9 shows the results of testing of the aphid Acyrthosiphon pisum (Homoptera) fed on artificial medium containing various concentrations of the TP protein.
DESCRIPTION OF THE INVENTION
[0018] The inventors have undertaken to investigate the toxic substance responsible for this mortality. It is, moreover, known that legumes contain several entomotoxic substances and that, in diverse species of insects for which legumes are toxic, there exist natural subpopulations which are more or less resistant to the toxicity of the legumes.
[0019] For example, in the case of grain weevils, a test carried out by the inventors' team on 90 strains of different geographical origins has shown that 4 strains belonging to the Sitophilus oryzae species include individuals capable of surviving to the adult stage on split peas; conversely, no strain having this ability has been revealed in the Sitophilus zeamais, or Sitophiius granarius species; the study of the genetic determinism of this resistance has shown that this property is monogenic, recessive and autosomal [GRENIER et al., Heredity, 79, pp. 15-23, (1997)].
[0020] The inventors have selected a strain of S. oryzae which is homozygous for this resistance gene, and have used this strain to investigate the toxic substance with respect to which the mechanism of resistance encoded by this gene is expressed.
[0021] The inventors have thus noted that this toxicity is associated with isoforms of a protein which has a sequence similar to that of the PA1b pea albumin (SEQ ID NO:7) described by HIGGINS et al. [J. Biol. Chem., 261 (24),pp. 11124-11130, (1986)], and which shows strong similarity (65% identity) with soybean leginsulin (SEQ ID NO:8) [WATANABE et al., Fur. J. Biochem., 15, pp. 224:1-167 72, (1994)]. No entomotoxic property had until now been associated with the PA1b protein (SEQ ID NO:7), with leginsulin or with other homologous proteins.
[0022] The alignment of the sequence of one of the isoforms of the protein purified by the inventors, with those of the pea PA1b protein (SEQ ID NO:7), published by HIGGINS et al., and of soybean leginsulin (SEQ ID NO:8), published by WATANABE et al., is represented in FIG. 7 . These 3 sequences include in particular 6 cysteine residues which occupy conserved positions.
[0023] A subject of the present invention is the use, as an insecticide, of a polypeptide comprising a sequence which satisfies the following general formula (I):
X 1 CX 2 CX 3 CX 4 CX 5 CX 6 CX 7 (I) (SEQ ID NO: 1)
in which C represents a cysteine residue, X 1 represents an amino acid or a sequence of 2 to 10 amino acids, X 2 represents an amino acid or a sequence of 2 to 5 amino acids, X 3 represents a sequence of 4 to 10 amino acids, X 4 represents a sequence of 3 to 10 amino acids, X 5 represents an amino acid or a sequence of 2 to 4 amino acids, X 6 represents a sequence of 7 to 15 amino acids, and X 7 represents an amino acid or a sequence of 2 to 10 amino acids. Preferably, X 1 represents a dipeptide, X 2 represents a tripeptide, X 3 represents a heptapeptide, X 4 represents a tetrapeptide, X 5 represents an amino acid, X 6 represents a nonapeptide, and X 7 represents a pentapeptide.
[0024] Advantageously:
X 1 satisfies the sequence y 1 y 2 in which y 1 and Y 2 each represent an amino acid chosen from alanine, serine, glycine and threonirie, or y 1 represents an amino acid chosen from alanine, serine, glycine and threonine, and Y 2 represents glutamic acid or aspartic acid; and/or X 2 satisfies the sequence y 3 y 4 y 5 in which y 3 represents glutamine or asparagine, and y 4 and y 5 each represent an amino acid chosen from alanine, serine, glycine, threonine, valine, leucine, isoleucine and methionine; and/or X 3 satisfies the sequence y 6 y 7 y 8 y 9 y 10 y 11 y 12 (SEQ ID NO:2) in which y 6 represents an amino acid chosen from alanine, serine, glycine and threonine, y 7 , y 11 and Y 12 each represent proline, y 8 represents an amino acid chosen from phenylalanine, tryptophan and tyrosine, y 9 represents aspartic acid or glutamic acid, and y 10 represents an amino acid chosen from valine, leucine, isoleucine and methionine; and/or X 4 satisfies the sequence y 13 y 14 y 15 y 16 (SEQ ID NO:3), in which y 5 and y 16 each represent an amino acid chosen from alanine, serine, glycine and threonine, or y 14 represents an amino acid chosen from alanine, serine, glycine and threonine, y 13 and y 15 each represent a basic amino acid, and y 16 represents aspartic acid or glutamic acid; and/or X 5 represents a basic amino acid; and/or X 6 satisfies the sequence y 17 y 18 y 19 y 20 y 21 y 22 y 23 y 24 y 25 (SEQ ID NO4), in which y 17 , y 19 , y 21 and y 23 each represent an amino acid chosen from valine, leucine, isoleucine and methionine, y 18 represents proline, y 20 and y 24 each represent an amino acid chosen from alanine, serine, glycine and threonine, y 22 represents an amino acid chosen from valine, leucine, isoleucine, methionine, phenylalanine, tryptophan and tyrosine, and y 25 represents an amino acid chosen from phenylalanine, tryptophan and tyrosine; and/or X 7 satisfies the sequence y 26 y 27 y 28 y 29 y 30 (SEQ ID NO:5) in which y 26 represents a basic amino acid or an amino acid chosen from valine, leucine, isoleucine and methionine, y 27 represents asparagine or glutamine or a basic amino acid, y 28 represents proline, and y 29 and y 30 each represent an amino acid chosen from alanine, serine, glycine and threonine
[0032] According to one preferred embodiment of the present invention, the polypeptide used as an insecticide shows at least 40%, preferably at least 60%, homology with any one of the isoforms of a PA1b albumin.
[0033] For the purpose of the present invention, the term “PA1b albumin” is intended to mean not only any isoform of the pea PA1b protein, but also any protein of the same family which is present in other plants and which can especially be purified from seeds of legumes, in particular legumes of the Cesalpinaceae, Mimosaceae or Fabaceae family, or of the Meliaceae family, such as Khaya senegalensis
[0034] Polypeptides which can be used in accordance with the invention may be natural polypeptides, for example leginsulins of legumes, such as the soybean leginsulin (SEQ ID NO:8) described by WATANABE et al they may also be artificial polypeptides, the sequence of which is derived from that of a PA1b (SEQ ID NO:7) by adding, deleting or substituting a small number of amino acids It is possible to use, for example, polypeptides comprising a sequence which satisfies the general formula (I), or a portion of this sequence which corresponds to the region involved in the insecticidal activity This active peptide can optionally be fused, at its N-terminal end and/or at its C-terminal end, with another peptide sequence.
[0035] These polypeptides can be obtained by conventional methods, known per se, for example by peptide synthesis, or by genetic engineering, by expressing, in a suitable host cell, a sequence encoding the desired polypeptide. They can also, in the case of natural polypeptides, such as PA1b (SEQ ID NO:7) and leginsulin (SEQ ID NO:8), be purified from seeds of plants such as legumes or Meliaceae.
[0036] In accordance with the invention, the polypeptides comprising a sequence of general formula (I) (SEQ ID NO:1) can be used as the only active principle of an insecticide, or combined with one or more other active principles. They can be used in particular for combating insects which are pests for cereal seeds, and also for combating plant-feeding insects, such as the lepidoptera Mamestra brassicae or Ostrinia nubilalis or the coleoptera Chrysomeiidae, for instance Phaedon cochieariae or Curculionidae, for instance Anthonomus grandis, or combating phloem-feeding insects such as aphids.
[0037] Furthermore, the inventors have noted that the PA1b protein (SEQ ID NO:7) conserves its insecticidal activity for several years in dry seeds, and that this activity is not affected by heating to 100° C.
[0038] In addition, this protein is not toxic for humans or higher animals; it is present in the legumes which form part of their conventional diet.
[0039] The polypeptides of general sequence (I) (SEQ ID NO:1) are particularly suitable for protecting, especially during storage, seeds, flours or transformed products which are derived therefrom.
[0040] For the implementation of the present invention, the concentration of the polypeptide of sequence (I) (SEQ ID NO:1) in the product to be protected (plant, seeds or derived products) is generally from 10 μmol/kg to 100 mmol/kg (or from 10 μM to 100 mM), and advantageously from 50 μmol/kg to 10 mmol/kg (or from 50 μM to 10 mM).
[0041] According to one preferred embodiment of the present invention, the product to be protected as treated with a preparation comprising said polypeptide. This polypeptide can, for example, be in the form of a purified preparation or of an enriched fraction, which can in particular be obtained from seeds of plants which product said polypeptide naturally, or from cultures of cells which express a gene encoding this polypeptide.
[0042] According to another preferred embodiment of the present invention, a transgenic plant is produced which is transformed. with at least one gene encoding said polypeptide, and which expresses the latter in at least one of its tissues or organs.
[0043] The present invention also encompasses the transgenic plants produced in this way; advantageously, said plants are cereals.
[0044] These plants can be obtained by the conventional techniques of plant transgenesis, which are known per se.
[0045] It is thus possible to obtain, in a plant, ubiquitous expression and/or expression and/or overexpression in certain tissues or organs (for example in seeds) of a polypeptide of sequence (I) (SEQ ID NO:1), and as a result, to protect the plant, tissue or organ concerned against attacks by insects for which this polypeptide is toxic. In particular, the expression of a polypeptide of sequence (I) (SEQ ID NO:1) in the seeds makes it possible to protect them, even after harvest, as well as the transformed products and flours obtained from these seeds.
[0046] The present invention will be more clearly understood with the aid of the following description which refers to nonlimiting examples, describing the purification, and illustrating the insecticidal properties, of a legume PA1b albumin.
EXAMPLE 1
Demonstration of the Toxicity of Various Legu Als For Cereal Weevils
[0047] The toxicity of meals from various legumes was tested on weevils (Sitophilus oryzae ) The experiments were carried out in parallel on wild-type animals (sensitive strain S), and on mutants surviving feeding on peas (resistant strain R).
[0048] The weevils (Sitophilus oryzae ) are bred in a chamber regulated at 27.5° C. and 70% relative humidity. One-week-old adults are removed from these mass breeding colonies for the tests, For each test, experimentation is carried out on batches of 30 insects, and daily mortality is noted.
[0049] Balls of meal are kneaded with water, left to dry for 24 h and used for feeding the weevils. The gray wheat flour used is supplemented with various proportions of legume meal, sieved using a mesh size of 0.2 mm. The dose-response curves for weevil mortality were obtained using various doses of each meal to be tested. The results are processed using the “Toxicologie” [Toxicology] program [FEBVAY and RAHBE, “Toxicologie”, un programme pour l'analyse des courbes de mortalité par la méthode des probits sur MacIntosh [“Toxicology”, a program for analyzing mortality curves using the probits method on a MacIntosh computer], Cahiers Techn. INRA, 27, pp. 77-78 (1991)]. This program uses the transformation of the cumulative mortalities into probits, and determines the regression curve equation and the concentration for 50% lethality. These values are determined after exposure for 4 and 7 days.
[0050] In addition, for each concentration of pea meal, the times for 50% lethality (LT50) for the sensitive strain S are also calculated. The calibration curve thus established makes it possible to determine, in the remainder of the experiments, for each meal or meal fraction tested, the equivalent concentration of pea meal (as % of pea in the wheat) This curve is given in FIG. 1 .
Pea Meal Toxicity
[0051] FIG. 2 shows the cumulative mortality for adults of the sensitive strain S of Sitophilus oryzae, on pea (⋄) and on wheat (□), as a function of the feeding time in days. These results show that the cereal weevils are rapidly killed on pea: in 8 days, between 90 and 100% of the adults are dead.
[0052] FIG. 3 shows the mortality at 6 days of Sitophilus oryzae, for balls containing various concentrations of pea meal; the resistant strain (R) and the sensitive strain (S) are compared. The dose/response curve thus established shows that, for the sensitive strain (S), from 10% of pea meal upward, 70% mortality s observed in 6 days (and 100% in 14 days) In the same period of time, the resistant strain (R) is not affected.
Toxicity of Other Legume Meals
[0053] Among the legume seeds used in the human diet, 10 were tested for their action on the sensitive and resistant weevils.
[0054] Balls containing 80% of legume meal and 20% of wheat flour were used. FIG. 4 illustrates the cumulative mortality of the Sitophilus oryzae weevils, resistant strain R or sensitive strain S measured after 5 ( 4 A) 7 ( 4 B), 14 ( 4 C) and 20 ( 4 D) days of feeding on cowpea (Vigna unguiculata) white (1) and red (2) variety bambora groundnut (3: Vigna subterranea ), lentil (4: Lens esculenta), French bean (5: Phaseolus vulgaris ), mung bean (6: Vigna radiata), adzuki bean (7: Vigna angularis), broad bean (8: Vicia faba), chickpea (9: Cicer arietinum), and lupin (10: Lupinus albus ).
[0055] The results show that, at 7 days, all the legumes are toxic for the sensitive strain, even though Vigna subterranea and Cicer arietinurn have not yet killed all the insects which live thereon; conversely, the resistant strain shows no or very little mortality. It can therefore be concluded that the same mechanism causing the toxicity is present in all these legumes; this mechanism appears in particular to be predominant in Vigna subterranea, Vigna radiata and Cicer arietinum.
[0056] However, examination of the mortalities at 14 and 20 days on certain legumes reveals, for the resistant strain, higher or lower mortality which must, therefore, be attributed to other mechanisms; this is in particular the case on Phaseolus vulgaris and on Vigna anguiaris.
EXAMPLE 2
Purification And Identification of the Substance Responsible For the Toxicity In Peas
Preparation of A Protein Fraction Enriched In Albumin (SRA1)
[0057] The fraction enriched in albumin is prepared on a pilot scale according to the protocol developed by CREVIEU et al, [Nahrung, 40 (5), pp. 237-244, (1996)].
[0058] The pea meal (10 kg) is mixed, with stirring, with 140 liters of acetate buffer (pH 49), the mixture is centrifuged at 7500 rpm and the supernatant is subjected to ultrafiltration on an MS membrane, at a temperature which does not exceed 25° C. The retentate is subject to diafiltration on the same membrane, the new retentate is centrifuged at 6000 rpm for 20 mm and the supernatant is lyophilized. The powder obtained (SRA1), which represents on average 1% of the mass used at the start, is used for the subsequent purifications.
[0059] At each step of the purification, the toxicity of the various fractions is determined according to the protocol described in Example 1 above.
Anion Exchange Chromatography
[0060] 10 g of SRA1 are suspended in 100 ml of a 60% methanol solution and stirred for 1 hour at 4° C. After centrifugation (30 mm, 9000 g, 4° C.), the supernatant is recovered and then the methanol present is removed in a rotary evaporator. The volume is then readjusted to 100 ml with water and a 1M Tris-HC1 buffer (pH 8.8) so as to obtain a final Tris-HCl concentration of 50 mM. The soluble proteins are fractionated by anion exchange chromatography on a DEAE SEPHAROSE FAST FLOW column (120×50 mm) The proteins adsorbed are eluted with a 50% concentration of buffer B (50 mM Tris-HCl, pH 8.8; 500 mM NaCl) in buffer A (50 mM Tris-HCl, pH 88). The elution flow rate is 20 ml/min and the fractions collected have a volume of 80 ml. The proteins are detected by absorption at 280 nm.
[0061] The chromatogram is shown in FIG. 5 . The concentration of buffer B is indicated by the broken line. The 80 ml fractions corresponding to the peaks are pooled into two main fractions, DEAE NA and DEAE 1, indicated on the chromatogram by the horizontal lines. The nonadsorbed fraction (DEAF NA) contains all the toxicity.
[0062] This fraction is dialyzed against water for 72 hours and then lyophilized. Approximately 450 mg of the DEAE NA fraction are thus obtained.
Semipreparative Reverse Phase HPLC Chromatography
[0063] The DEAE NA fraction obtained after anion exchange chromatography is fractionated by reverse phase HPLC (RP-HPLC) chromatography on a HYPERSIL column (250×10.5 mm) filled with C18-aliphatic-chain-grafted 5 μm 300 Å NUCLEOSIL. For each chromatography, 15 mg of proteins are loaded on to the column. The elution flow rate is 3 ml/min and the proteins are detected by absorption at 220 nm. The proteins are eluted with a gradient of buffer B (004% of trifluoroacetic acid in acetonitrile) in mixture A (0.04% of trifluoroacetic acid in water) according to the following sequence: t=0 mm, 40% of B; t=5 mm, 40% of B; t=17 mm, 48% of B; t=18 mm, 80% of B; and t=23 mm, 80% of B.
[0064] The chromatogram is illustrated in FIG. 6 , The acetonitrile gradient is represented by the broken line. The toxicity is located only in the peaks Fl and TP; the fractions corresponding to these peaks which have been collected are represented on the chromatogram by horizontal lines.
[0065] Thirty successive chromatographies, corresponding to an injected amount of DEAF NA of 450 mg, were carried out. The fractions were pooled and then lyophilized after evaporating off the acetonitrile and the trifluoroacetic acid in a SPEED VAC, 4 mg of the TP fraction and 5 mg of El were thus obtained.
[0066] These fractions were then analyzed by reverse phase HPLC (RP-HPLC) chromatography.
Reverse Phase HPLC Chromatograghy
[0067] The control of the purity of the proteins of the Fl and TP fractions is carried out by reverse phase HPLC chromatography on an INTERCHROM column (250×4.6 mm) filled with C18-aliphatic-chain-grafted 5 μm 100 Å NUCLEOSIL. The elution flow rate is 1 ml/min and the proteins are detected by absorption at 220 nm.
[0068] The proteins are eluted in 45 minutes with a linear gradient of 0 to 50% of mixture B (0.04% of trifluoroacetic acid in acetonitrile) in mixture A (0.04% of trifluoroacetic acid in water).
[0069] This analysis shows that the TP fraction contains only the toxic protein TP (SEQ ID NO:6). The Fl fraction is more complex and contains two major polypeptides.
Characterization of the Proteins Present In the Fractions TP And Fl
[0070] The mass determinations were carried out by electrospray mass spectrometry (ES-MS). The mean masses calculated from 2 estimations are 3741.1 Da in the case of TP, and 3736 and 3941 Da for the polypeptides of the TF fraction. The number of cysteines free and involved in disulfide bridges was determined by alkylating the protein with iodoacetamide, before and after reduction, and comparing the retention times, by RP-HPLC, and the masses, by ES-MS, of the alkylated proteins with the native protein.
[0071] The alkylated nonreduced protein has both a retention time and a mass identical to that of the native protein. On the other hand, the protein which is reduced and then alkylated has a retention time which is clearly different from that observed for the native protein (30 mm instead of 42 mm) and a mass of 4089.9 Da.
[0072] It appears therefore that this protein contains 6 cysteines, which are all involved in 3 disulfide bridges.
Complete Sequence of the TP Protein
[0073] The complete sequence of the TP protein (SEQ ID NO:6) was established. The mass calculated from the 37 residues of the protein is 374L4 Da, which is identical, give or take the measurement error, to that determined by mass spectrometry (3741.1 Da) for the native protein. The value calculated for the protein alkylated with iodoacetamide (4090 Da) is also equivalent to that obtained experimentally (4089.9 Da). These results demonstrate the absence of post-translational modifications (glycosylations, phosphorylations, etc.) of the protein.
[0074] The sequence of the TP protein (SEQ ID NO:6) shows very strong homology with that of the PA1b pea albumin (SEQ ID NO:7) [HIGGINS et al, J. Biol. Chem, 261 (24), pp. 11124-11130, (1986)]. The two sequences differ only by the replacement of the valine residue at position 29 in the TP protein (SEQ ID NO:6) with an isoleucine in PA1b (SEQ ID NO:7). Strong similarity (62% identity, 89% homology, determined with the aid of the MAC MOLLY program using the BLOSUM62 matrix) is also observed between the TP protein (SEQ ID NO:6) and soybean leginsulin (SEQ ID NO:8) [WATANABE et al., Eur. J. Biochem., 15, pp. 224:1-167-72, (1994)] In particular, the 6 cysteine residues, which play an essential role in the structure of the proteins, occupy conserved positions.
[0075] The comparison of these 3 sequences is shown in FIG. 7 .
[0076] These results make it possible to conclude that the protein responsible for the resistance of pea to cereal weevils is similar to the PA1b protein (SEQ ID NO:7) described by HIGGINS. This protein is synthesized in the form of a 130-residue preproprotein (PAl) which undergoes post-translational maturation releasing the PA1b protein(SEQ ID NO:7) and a 53-residue protein named PA1a [HIGGINS et aL, J. Biol, Chem, 261 (24), pp. 11124-11130, (1986)].
[0077] Sequencing of the first 10 N-terminal residues of each of the toxic polypeptides of the Fl fraction was also carried out. The sequences obtained are identical to that of the N-terminal end of the TP protein. As, in addition, the masses of these polypeptides determined by ES-MS are very close to that of TP, it appears that these polypeptides represent isoforms of TP.
EXAMPLE 3
Activity And Stability of the Entomotoxic Proteins Extracted From Peas
[0000] Activity
[0078] The entomotoxic activity of the polypeptides of the TP fraction or of the Fl fraction was determined as described in Example 1 above; at the concentration of 1% in the wheat flour (3 mmol/kg), these polypeptides have a toxicity for the weevil which is equivalent to that of pure pea meal. A concentration of 60 tmol/kg is sufficient to prevent any infestation by the weevils.
[0000] Stability
[0079] The polypeptides of the TP fraction or of the Fl fraction, extracted from dried seeds stored for several years, conserve their entomotoxic activity. In addition, this activity is not affected by heating to 100° C.
[0000] Toxicity For Various Insects
[0080] The toxicity of the TP protein for the flour moth Ephestia kuehniellea (Lepidoptera) and for the aphid Acyrthosiphon pisum (Homoptera) was also tested.
[0081] The tests on the flour moth were carried out on first and second stage Ephestia kuehniella larvae fed on wheat flour balls containing various concentrations of the TP protein (In mmol per kg of wheat flour). The results are shown in FIG. 8 .
[0082] (◯=survival at 0 days;
[0083] ▴=survival at 4 days;
[0084] □=survival at 10 days).
[0085] These results showed that this protein was very toxic, from the concentration of 0.25 mmol/kg upward.
[0086] The aphid Acyrthosiphon pisum (Homoptera) was fed on artificial medium containing various concentrations of the TP protein.
[0087] (□=3.3 μM;
[0088] ◯=17 μM;
[0089] ♦=46 μM;
[0090] ◯=84 μM;
[0091] =100 μM).
[0092] The results, which are shown in FIG. 9 , show that considerable mortality appears from the concentration of 46 μmolar upwards this mortality being total at 100 μmolar. | The invention concerns the use of a polypeptide derived from a PA1b legume albumen as insecticide, particularly for protecting cereal grains against insect pests. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to a valve train for an internal combustion engine or the like and more specifically to a variable valve timing arrangement therefor.
2. Description of the Prior Art
In a known arrangement such as shown in FIG. 1 of the present application, it has been proposed to operate a poppet valve, such as an inlet or exhaust valve of an internal combustion engine, via a rocker arm 1 which engages a cam 2 at one end and which is pivotally mounted on top of the stem 3 of the valve 4 at the other end. The upper surface of the rocker arm 1 is contoured and adapted to abut a lever 5. The point of abutment with the lever 5 defines the pivot or fulcrum point of the rocker arm. With this arrangement as the cam 2 rotates the rocker arm 1 is cammed to pivot about the fulcrum point defined by the aforementioned contact and induce the valve 4 to reciprocate. To vary the timing and degree of lift the valve 4, a second cam 6 is provided and adapted to abut the lever 5. The second cam 6 is selectively rotated by a suitable hydraulic motor or the like (not shown). Thus, if the second cam 6 is rotated in a direction to urge the lever 5 to rotate counter-clockwise (viz., downwardly as seen in the drawings) the degree of valve lift and the duration for which the valve is open will be increased. Rotation of the cam which allows the lever to point in the clockwise direction (as seen in the drawings) reduces the valve lift and the duration for which the valve is open.
However, this arrangement has suffered from the drawbacks that the provision of the cam and lever arrangement above the rocker arm increases the overall height of the engine and, as the lever/cam arrangement does not permit ready adjustment of the clearance between the rocker arm and the top of the valve stem, a rather large clearance must be provided to allow for thermal expansion, wear etc. This clearance unavoidably leads to the generation of so called "tappet noise", vibration and also tends to deteriorate the valve timing itself. A further drawback comes in that, in the case the above disclosed arrangement is applied to an engine having four or more cylinders, as the cams are usually disposed on the same common cam shaft for the purpose of simplicity, the shaft is constantly subjected to reaction forces produced by the valve springs acting thereon through the rocker arms and levers which forces tends to rotate the shaft back against the bias applied by the servo. These forces tend to peak during engine operation as each valve lift reaches its zenith and the fulcrum point defined between each lever and rocker arm moves in the direction of the cam. Thus, in the case wherein a single servo is connected to one end of this cam shaft, it must be able to produce sufficient power to both maintain the shaft in any given desired position against this reaction force as well as overcoming the friction generated between the bearings etc., of the shaft by the reaction force when it is desired to vary the valve timing.
This latter drawback is particularly manifest in four cylinder engines wherein a valve is always being lifted.
One method for overcomming this problem would be to provide a servo and cam shaft for each valve, however this would lead to a prohibitively complex arrangement which would be both heavy and difficult to precisely control. For a complete disclosure of the above described arrangement reference is made to U.S. Pat. No. 3,413,965 issued on Dec. 3, 1968 in the name of J. M. Gavasso.
SUMMARY OF THE INVENTION
The present invention features an arrangement wherein a telescopically extendible hydraulic tappet pivotally supports one end of an angled rocker arm and wherein a reaction member located above the rocker arm induces the latter to pivot once the tappet, under the influence of a cam has lifted the rocker arm sufficiently to engage an apex thereof against the reaction member. The tappet includes a piston which defines a variable volume chamber therein into which hydraulic fluid may be readily introduced but only slowly discharged. An electronically controlled valve controls the pressure fed to the chamber in accordance with a plurality of variables. By varying the pressure in the chamber and thus the degree of extension of the tappet, the degree of valve lift induced by the rocker arm can be varied.
BRIEF DESCRIPTION OF THE DRAWINGS
The features and advantages of the arrangement of the present invention will become more clearly appreciated from the following description taken in conjunction with the accompanying drawings in which:
FIG. 1 is a partially sectioned view of the prior art arrangement discussed in the opening paragraphs of the instant disclosure;
FIG. 2 is an elevation (partially in section) of a first embodiment of the present invention;
FIG. 3 is a schematic diagram showing the arrangement of FIG. 2 with a suitable hydraulic control circuit for controlling the degree of pressurization and subsequent extension of a telescopic hydraulic tappet which forms a vital part of the invention;
FIGS. 4 and 5 are elevations showing the hydraulic tappet extended to induce maximum valve lift;
FIGS. 6 and 7 are views similar to FIGS. 4 and 5 but showing the hydraulic tappet set to induce minimum valve lift;
FIG. 8 is a graph showing the terms of valve lift and crank angle, maximum and minimum valve lifts possible with the various embodiments of the present invention;
FIG. 9 shows a second embodiment of the present invention wherein the lever and rocker arm are mechanically interconnected to prevent relative slip therebetween during valve lift operation;
FIGS. 10A and 10B show a third embodiment of the present invention wherein a torsion spring replaces the coil springs of the previous embodiments;
FIG. 11 is a sectional elevation showing a fourth embodiment of the present invention wherein an additional hydraulic cylinder arrangement is provided for maintaining the valve clearance between the rocker arm and the valve stem at zero throughout all modes of operation;
FIGS. 12 and 13 are schematic elevations showing the fourth embodiment with the hydraulic tappet thereof set for maximum valve lift; and
FIGS. 14 and 15 are views similar to those of FIGS. 12 and 13 but showing the hydraulic tappet set for minimum valve lift.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Turning to the drawings and in particular FIG. 2, a first embodiment of the present invention is shown. In this arrangement a poppet valve 10, which may be either an inlet or an exhaust valve, is operatively disposed in an internal combustion engine cylinder head 12. This valve 10 is biased to a closed position under the influence of a nest of coil springs 14. A cam 16 having a lobe 17 is mounted on an overhead cam shaft 18 disposed in a suitable elongate bore 20. A telescopic hydraulic tappet unit 22 is reciprocatively disposed in the cylinder head so as to contact the cam at one end thereof and pivotally support an angled rocker arm 24 at the other end thereof. A reaction member 26 fixedly mounted in place on two parallel shafts 28, 30 is formed with an elongate slot 32 in which an essentially flat surface 34 is defined and against which the upper surface 36 of the rocker arm 24 is engageable. A spring 38 is disposed between the end of the reaction member 26 and the end of the rocker arm 24 which is pivotally mounted on a dome-like projection formed at the top of the telesopic tappet 22.
The telescopic tappet unit 22 includes a piston 40 reciprocatively disposed in a hollow cylinder 42 to define a closed variable volume chamber 44 therein. The piston 40 itself is formed with a fixed volume chamber 46 which communicates with the variable volume chamber 44 through a one-way check valve 48 (in this case a ball valve). The fixed volume chamber 46 is adapted to constantly communicate with an oil gallery 50 through radial bores and intervening recesses. With this arrangement the hydraulic pressure prevailing in the oil gallery 50 is transmitted via the fixed volume chamber 46 and the one-way check valve 48 to the variable volume chamber 44. Disposed within the chamber 44 is a spring 52 which biases the piston 40 to project out of the cylinder 42.
FIG. 3 shows an example of a hydraulic control circuit which may be used to control the fluid pressure prevailing in the oil gallery. In this arrangement an oil pump 54 supplies hydraulic fluid under pressure to an electromagnetic valve 56 which modulates the output of the pump 54 in accordance with a control signal fed to the solenoid 58 thereof from a control circuit 60. The control circuit receives and computes various inputs indicating pararameters such as engine speed, intake air volume, and engine coolant temperature and issues an energizing signal via which the valve is energized. The latter mentioned parameter is of importance to allow for the temperature change of the fluid fed to the telescopic tappet 22 and prevent any undesired change in the extension thereof. The output of the valve 56 is fed to the oil gallery 50 as shown and therefrom to the variable volume chamber 44 as previously described.
FIGS. 2, 4 and 5 show the hydraulic tappet 22 fully extended for inducing maximum valve lift. In operation, as the cam 16 rotates and the lobe 17 thereof engages the bottom of the cylinder 42, the unit as a whole tends to be driven upwardly. During the initial stage of the lift operation, the spring 38 is firstly compressed and the rocker arm 24 induced to move upwardly until the apex 62 (defined of the elbow of the angled rocker arm) of the arm 24 engages the flat surface 34 formed on the reaction member 26, whereafter the arm 24 pivots and drives the valve 10 down against the bias of the nested springs 14. As the valve 10 is moved against the bias of the springs 14, the piston 40 tends to be driven down slightly into the cylinder 42 by the resulting reaction compressing the fluid trapped in the variable volume chamber 44 until a predetermined pressure is reached whereat the fluid acts as a "quasi" solid body.
It should be noted that during each of the lift operations, some of the fluid trapped in the variable volume chamber 44 tends to escape through the clearances defined between the piston 40 and cylinder 42 and even via the one-way check valve 48, however the amount of oil lost is negligible and immediately replaced at end of each lift operation wherein the bottom of the cylinder 42 rides on the base circle of the cam 16 and the spring 38 urges the piston 40 back to its original position.
FIGS. 6 and 7 show the tappet 22 with the piston 40 fully retracted into the cylinder 42 for minimum valve lift. To achieve this, the pressure in the oil gallery 50 is reduced via the operation of the electromagnetic valve 56 whereafter the fluid trapped in the variable volume chamber 44 is gradually expelled via the aforementioned clearances until the pressure in the chamber 44 and the fixed volume chamber 46 become equal. With the piston 40 fully retracted, the distance between the apex 62 of the rocker arm 24 and the surface 34 of the reaction mixture 26 tends to maximize (as shown in FIG. 6) so that during the initial stage of the lift operation the rocker arm 24 must be moved through a relatively large distance before engagement of the apex 62 with the surface 34 and subsequent movement of the valve 10. Thus, when the peak of the cam lobe 17 engages the bottom of the cylinder 42, the valve 10 is lifted by only a small amount as compared with the maximum valve lift operation wherein the apex 62 makes contact with the reaction member 26 after moving through only a relatively short distance.
FIG. 8 is a graph showing possible maximum and minimum valve lifts which may be produced by the embodiments of the present invention. It should be noted however, that it is possible to have a zero valve lift (viz., disable the valve) if so desired. This is of course achieved by increasing the distance defined between the apex of the rocker arm and the reaction member (via appropriately designing the tappet etc.) a little more than shown in FIG. 6.
FIG. 9 shows a second embodiment of the present invention. This arrangement differs from the previously described arrangement in that the rocker arm 24 and the reaction member 26 are mechanically interconnected to prevent relative slip between the two members during operation. The mechanical connection takes the form of a shaft (not labelled) rotatably disposed through essentially the midpoint of the rocker arm and a pair of forks 66 which extend down from the reaction member on either side of the rocker arm. The rotatable shaft is formed with flats 68 thereon which slide on the opposed walls of the slots 70 defined by the forks 66.
FIGS. 10A and 10B show a third embodiment of the present invention. In this arrangement the coil spring of the previous embodiments is replaced with a single torsion spring 71 (shown in FIG. 10B) which is adapted to seat between and clip onto both of the rocker arm 24 and the reaction member 26.
FIG. 11 shows a fourth embodiment of the present invention which resembles the first embodiment but features the provision of a hydraulic cylinder 72 which continuously maintains a zero valve clearance between the rocker arm 24 and the valve stem and a reaction member 74, which in this case is pivotally mounted on a shaft 76 as differentiated from the fixed arrangement of the previous embodiments. The construction of the hydraulic cylinder 72 is essentially the same as that of the tappet 22. The bias applied to the reaction member 74 by the cylinder 72 and which tends to rotate the reaction member 74 in the clockwise direction, is of course notably less that the bias produced by the nested springs 14 so as not to unwantedly open the valve 10 but merely to press the end of the rocker arm 24 in contact with the top of the valve stem, against the stem with a force adequate for reducing the clearance therebetween to zero.
Thus, if due to any one of a number of well known reasons a clearance develops between the rocker arm and the valve stem, the hydraulic cylinder tends to elongate under the influence of the spring 78 disposed therein whereby additional hydraulic fluid is inducted into the variable volume chamber 80 thereof. The reaction member 74 is accordingly rotated slightly to close the clearance. Conversely, if an excessive surface pressure is developed between the stem and the rocker arm, the reaction member 74 tends to rotate in the counter-clockwise direction compressing the hydraulic cylinder 72. Under these conditions fluid is slowly displaced from the variable volume chamber via clearances defined between the piston 82 and cylinder 84 thereof and via a one-way check valve 86 (a hermetic seal not being provided therebetween). Accordingly, the degree of extension of the hydraulic cylinder 72 slowly decreases until the desired zero valve clearance maintaining equilibrium is re-established.
FIGS. 12 and 13 show the operation of the fourth embodiment with the telescopic hydraulic tappet 22 extended to produce maximum valve lift. As apparent from the drawings the operation of this arrangement is essentially the same as the previously disclosed embodiments, however at the time the cam lobe 17 induces the maximum rotation of the rocker arm 24, the apex 62 engages the reaction member at a point which tends to product the minimum moment of force tending to rotate the reaction member 74 about the axis of rotation of the shaft 76 in counter-clockwise direction.
Conversely when the telescopic tappet 22 is set to produce the minimum valve lift as shown in FIGS. 14 and 15, the apex 62 of the rocker arm 24 engages the reaction member 74 a point displaced further from the axis of rotation of the shaft 76. However, as the degree of valve lift is small (or even zero) the reaction produced by the nested springs 14 is relatively small so that the resulting effect on the reaction member is accordingly small. | A reaction member located above an angled rocker arm induces the latter to pivot once a telescopically extendible hydraulic tappet, under the influence of a cam, has lifted the rocker arm sufficiently to engage an apex thereof against the reaction member. The tappet includes a piston which defines therein a variable volume chamber into which hydraulic fluid may be readily introduced via a solenoid control valve, but only slowly discharged. The degree of extension of the tappet controls the valve lift induced by the rocker arm. | 5 |
FIELD OF THE INVENTION
[0001] The present invention relates to the field of network computing. In particular, it relates to a method and respective system for providing access to remote resources for an application program via remote services.
BACKGROUND
[0002] FIG. 1 gives an overview over prior art system architecture.
[0003] The overall system 1 comprises a remote computer 3 and a local computer 2 with a network connection through network services 4 .
[0004] A local computer 2 is a system which executes application programs 21 and host access to a file 2511 on a file system 25 .
[0005] An application program 21 is to be understood as an executable file on the local computer 2 which needs access to files through environment variable definitions. Therefore, it calls so-called environment variable access services 211 .
[0006] With such prior art technology it is possible to access data from a local file system by an application program running on a local computer. It is also possible to transparently access even data from a remote computer through the local file system management which is mounted to it. So, the present invention addresses all application programs or systems which do not care about network access today and just rely on local data access from their specific point of view.
[0007] With the increasing use of the Internet the need to transparently access data beyond the scope of mounted file system arises. If data resides on the Internet or even in the Intranet data is normally not available through such file sharing mechanism for several reasons and can often only be accessed via browser based services using URL locations. This however is disadvantageous because many application programs do not have a Browser functionality incorporated with them.
SUMMARY OF THE INVENTION
[0008] One objective of the present invention is to provide a mechanism for local running application programs which enables them to dynamically use also URL-addressed data in the Internet or an Intranet without any change in their program source code. This objective of the invention is achieved by the features stated in enclosed independent claims. Further advantageous arrangements and embodiments of the invention are set forth in the respective subclaims. Reference should now be made to the appended claims.
[0009] The present invention uses the idea that a programmer can define through some environment variables the URL location to be searched and that the operating system when encountering the read of the environment variables provides the associated data for local access, such that an application program referring to the environment variable search path does not know if the data is found on the URL location or through the traditional file system layer.
[0010] A programmer skilled in the art is able to put the required URL definitions into the environment variable. The URL definitions follow the official URL standards which include a file, HTTP, FTP or other access mechanisms. As implied by the handling of environment variables according to prior art the operating system has the task to provide the access to the location, the operating system provides respective services to the application program which uses the inventional form of an environment variable. Further below, those services are called “remote data access service” and “remote data provider service”, on the local and the remote computer system, respectively.
[0011] A preferred implementation of such service which is transparent to an application program includes the idea of creating a new type of environment variable which can be defined as a “dynamic variable”. The processing of such new variable can be either defined in a system provided configuration field which can be implemented specific for the operating system in use, or a new reserved system environment variable such as “dyn vars” can be created which lists just the dynamic environment variables. An example can be:
[0000] Dyn vars=x_path (1 min), y_path (10 min), z_path (6 h); the time indications are the default refresh times after which a URL is checked again and is eventually updated.
[0012] An alternative method discloses to define a reserved posed or prefix indicator to a variable in order to mark a variable as dynamic. Examples could be:
[0000] x_path (1 min)=http://svn.apache.org/viewvc/ant/core/trunk/src/resources/
or
y_path ( )=http://svn.apache.org/viewvc/unt/core/trunk/src/resources,
where the refresh time is a default setting.
[0013] A variable defined as “dynamic” triggers the operating system to create a so-called shadow area for each URL which contains the data references by the URL. Thus, a kind of shadow pool storage area can be created which will by synchronized on a predefined time interval, referred to as “refresh” time. As seen above the synchronization parameter may be also implemented as a part of the definition, the variable is a dynamic variable. The location of the shadow storage pools is defined somewhere within the operating system configuration. In addition a file system listener may be activated which detects access to files in such shadow pool area. If so then this may trigger the update of the requested file or files from the remote location instead of the regular interval. This would allow a consistent local cache to the remote sources.
[0014] The advantage thereof is that when an application program reads the environment variable the URL can be replaced by the shadow location on the file system, which is thus transparent for the application program. So, as a person skilled in the art, may appreciate, the source code of an application program does not need to be changed, when the inventional features are to be implemented.
[0015] A further implementation of the inventional method includes to provide new services for accessing the information encoded by such environment variable, which allows to the operating system to search for a file in a search path which, if the path is found, also makes the file accessible for read access. By this method an application program is then enabled to query on request the URL resource just in time, find i.e. locate the file for example as indicated by a directory location, and, if requested, even makes the file locally accessible. The location of the requested resource is just a verification if the URL is a valid URL and if a real resource is found behind such definition. The actual access to the remote data involves then a download from the URL location to a local area (shadow area as described above) for enabling an access of the program through prior art access methods which are now redirected to point to the download path. So, the application program only defines the environment variable containing the URLs and the members to access and will get back then the real location of the member in the file system. The verification of the URL and the download itself are then services performed by the underlying operating systems which are hidden to the application program.
[0016] According to the most basic aspect of the present invention as claimed further below, a method for providing access to remote resources for an application program performed by a part of the operating system of a network-connectable computer, preferably performed by an “extended environment variables manager”, is disclosed,
[0000] which is characterised by the steps of:
a) scanning the values of environment variables of said application program for the occurrence of an URL notation,
b) invoking a remote function for accessing an URL found in said scanning procedure in order to request a remote resource associated with said URL,
c) storing said remote resource in a pre-allocated cache memory section,
d) listening to the access of the pre-allocated cache memory to make sure the most current data is stored in the cache memory if not an update will be initiated.
[0017] Preferably, the remote resource is selected from the group of:
[0000] a) one or more files stored in a remote file system,
b) one or more directories containing files in a remote system,
c) repositories or databases holding information that can be stored as local file instances.
[0018] Preferably, the basic method can be extended by a sequence of steps as follows:
[0000] a) if a URL location is found in said scan step above, checking if a local cache memory section exists which is allocated for the remote resource associated with said URL notation,
b) in case no memory section exists, allocating a respective section, and storing said remote resource a local cache memory section,
c) in case an allocated memory section exists, storing said remote resource at said local cache memory section.
[0019] Further, a second component, e.g. an environment variable value provider performs the method for providing access to remote resources for an application program via an environment variable, which is characterized by the steps of:
[0000] a) in response to a request from an application program requesting the value of an environment variable,
b) scanning the environment variables value for a URL notation,
c) if a URL notation is found replace said URL notation by a reference pointing to the cache memory section
d) initiate and file system listener for the cache memory to verify consistency to remote data location.
[0020] The before mentioned environment variable manager and environment variable value provider cooperate quite closely by using an appropriate operational programming interface. The controller works preferably asynchronically to the runtime of the application program and provides the respective URL data. At the runtime of a compiled and executable application program the environment variable is read by the provider component which forwards at least the cache copy of the data generated by the controller program in the file cache, if it is not available, a respective error message is issued.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] The present invention is illustrated by way of example and is not limited by the shape of the figures of the drawings in which:
[0022] FIG. 1 illustrates the most basic structural components of a prior art hardware and software environment used for a prior art method,
[0023] FIG. 2 illustrates the most basic structural components of a inventional hardware and software environment used for a preferred embodiment of the inventional method,
[0024] FIGS. 3A and 3B illustrate the control flow of the most important steps of a preferred embodiment of the inventional method,
[0025] FIGS. 4 , 5 , and 6 show sample implementations of certain aspects used by the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0026] With general reference to the figures and with special reference now to FIG. 2 the structural and functional components as used in a preferred embodiment of the invention are described. Some of them are used as existing in prior art, others are modified in order to comply with the requirements of typically inventional functionality and structure.
[0027] FIG. 2 gives a system description.
[0028] The overall system 1 comprises a remote computer 3 and a local computer 2 with a network connection through network services 4 .
[0029] A local computer 2 is a system which executes application programs 21 and host access to a file 2511 on a file system 25 .
[0030] An application program 21 is to be understood as an executable file on the local computer 2 which needs access to files through environment variable definitions. Therefore, it calls so-called environment variable access services 211 . In so far, this corresponds to FIG. 1 .
[0031] With reference to environment variable access services 211 , there are given further below several sample access methods in various programming languages which allow retrieving the content of environment variables for further processing by the application program. For environment variables pointing to file location information a data access service may be called to retrieve files from the specified location path.
[0032] An essential element of a prior art application program is the so-called Data access service 212 .
[0033] This section of the application program will get the location path information as a sequence of data location specification which may typically come from environment variables, or alternatively from application invocation parameters. Based on this input the application will try to get access to the content of one or more files potentially located in the given location search path. So, for each path the service will try to access the file and if it is found, the content of the file will be referred, or if it is an output location a file may be written to. If a file system 25 listener is active then this may even trigger a update of created files to a remote system if this configured and access right are given.
[0034] A Command Shell 22 is a further component of the local computer's 2 operating system, which represents the interface to its user to define and change an environment variable definition 22 a by a keyword and an associated value 242 . The entered format it passed to a so-called environment variable manager 24 for purpose of internal representation.
[0035] Also requests to display a stored environment variable will come through the Command Shell 22 where it will request the information of the environment variable or variables and display them in its presentation space.
[0036] The implementation of the command shell 22 depends on the operating system; there might be even different versions available for the same operating system.
[0037] WINDOWS and UNIX have a similar way treating environment variables while IBM z/OS for example works differently. However, regarding the aspect of file specifications through keyword references there is a high degree of similarity. On IBM z/OS one can specify either through the command shell time sharing option (TSO) or through the Batch submission system JES via JCL a DDNAME which allow to define a keyword known to the calling application program and a sequence of data sets names (which correspond to file paths in WINDOWS or UNIX).
[0038] An Environment Variable Definition Command 22 a shows a command and its syntax to define an environment variable to the application environment provided by the underlying operating system through a command shell environment. The definition can be done through various ways. A user may type-in the command in a command shell. The command can be executed through shell scripts. A GUI interface may be provided to enter the environment variable definition.
[0039] An Environment Variable keyword 22 b represents the name of the environment variable used in the application program to refer to the associated value.
[0040] A file system path 22 c may be directed to a local location; an example is given in the drawing to specify a directory path which may map to the directory location 251 a of the local system 2 .
[0041] A file system path 22 d may be directed to a remote location; an example is given in the drawing to specify a directory path which may map to the remote directory location 351 a which is part of the local file system 2 through a file share access via a remote data access service 23 and the remote data provider service 31 of the remote computer 3 .
[0042] A file system path 22 e may be directed to a local location; an example is given in the drawing to specify a directory path which may map to the directory location 251 b.
[0043] An Environment Variable value 22 f is given in the drawing to comprise elements 22 c , 22 d , and 22 e . The content of an environment variable keyword to be referred to from an application program through the keyword. The format of the value is not strictly defined. It can be of any string. However, for specifying path and file locations a special syntax has been established where an application program can rely on, and which allows to define a path as a path list where each path is separated in windows through a ‘;’, wherein in UNIX the ‘:’ is used. A system defined variable is the path variable to hold the location of an executable program file to be searched when it is called in the command line window for execution.
[0044] Other common variables are classpath for a Java Virtual Machine or lib to contain dynamic calls. Also definitions for help files, include files for compilers and other file related variables do exist. On IBM z/OS the concept of a DDNAME is used to locate to a name a path of datasets to be searched. In this way a DDNAME can be seen as an environment variable with a key/value pair. The mechanism to define the variable is different but the concept is the same.
[0045] An Environment variable user service 221 is a service as part of the command shell of an operating system having the functionality to define and retrieve the environment.
[0046] A Remote file access service 23 implements a method which allows requesting data from a remote data provider through a file server in order to mount remote file storage to the local file system 25 . A file listener may be associated to enable a life update of files accessed or created by application program 21 .
[0047] An Environment Variable Manager 24 will manage the list of defined environment variables entered and modified through service 211 or service 221 .
[0048] An Environment variable table 240 contains the key-value pairs of pre-defined environment variables. In reality there might be several tables with different scopes for a multi user system, or one table works for all users and others are private for each individual users. Manager 24 then will create a search path through the tables for the same environment variable if needed.
[0049] An Environment variable key 242 will represent an environment variable keyword in the list to represent an associated value located in column 242 of table 240 .
[0050] An Environment variable active value 242 will represent the actual environment variable value associated to a column 241 that gets used by an application program 21 through service 211 .
[0051] A file system 25 provides the permanent storage location for files in the local computer system 2 and a file system listener for changes and access to the shadow pool area.
[0052] A path location 251 provides the location of the files to be stored within the file system 25 .
[0053] A file 2511 contains the permanent data to be stored in the file system 25 at a defined path location 251 a or 251 b.
[0054] A remote computer 3 is connected to the local computer 2 through a network connection 4 which allows to transfer file data between the two file systems 35 and 25 , respectively.
[0055] A remote data provider 31 is a service on the remote computer 3 that allows to access files from a local computer 2 through the local file system 25 access layer in the way that the remote data is virtually seen as local data. Examples of such services are LAN share, AFS, NFS or SAMBA.
[0056] The remote file system 35 plays the same function on the remote system 3 as does the file system 25 on the local computer 2 .
[0057] The remote path locations 351 a 351 b have the same function on the remote system 3 as the path location 251 a, b have on the local computer 2 . The same is true for the remote files 3511 a - d.
[0058] Network services 4 are prior art methods to allow the communication and data transfer between a remote data provider 31 and a remote data access service 23 .
[0059] The command 22 shell is extended according to the invention by additional services to retrieve not only the traditional format by also the entered value of environment variable definition command 22 a . It may also extended by services to allow a further configuration for an extended table 240 to define caching intervals and caching locations for individual remote references.
[0060] Note that for the invention the traditional command shell is relevant, however for user interaction to define, modify and display environment variables, alternate user interfaces such Graphical User interfaces (GUI) may be provided as alternative to the command shell. However, those will interact in the similar way to table 24 as the Command Shell will do with table 24 as it exists in prior art.
[0061] For a preferred embodiment of the invention implemented in IBM z/OS Operating system the prior art concept and utility of the DDNAME will be extended as described.
[0062] An Environment variable user service 221 is a service as part of the command shell of an operating system having the functionality to define and retrieve the environment.
[0063] A Remote file access service 23 implements a method which allows to request data from a remote data provider through a file server in order to mount remote file storage to the local file system 25 .
[0064] An Environment Variable Manager 24 will manage the list of defined environment variables entered and modified through service 211 or service 221 .
[0065] An Environment variable table 240 contains the key-value pairs of pre-defined environment variables. In reality there might be several tables with different scopes for a multi user system, or one table works for all users and others are private for each individual users. Manager 24 then will create a search path through the tables for the same environment variable if needed.
[0066] An Environment variable key 242 will represent an environment variable keyword in the list to represent an associated value located in column 242 of table 240 .
[0067] An Environment variable active value 242 will represent the actual environment variable value associated to a column 241 that gets used by an application program 21 through service 211 .
[0068] A file system 25 provides the permanent storage location for files in the local computer system 2 and a file system listener for changes and access to the shadow pool area.
[0069] A path location 251 provides the location of the files to be stored within the file system 25 .
[0070] A file 2511 contains the permanent data to be stored in the file system 25 at a defined path location 251 a or 251 b.
[0071] A remote computer 3 is connected to the local computer 2 through a network connection 4 which allows to transfer file data between the two file systems 35 and 25 , respectively.
[0072] A remote data provider 31 is a service on the remote computer 3 that allows to access files from a local computer 2 through the local file system 25 access layer in the way that the remote data is virtually seen as local data. Examples of such services are LAN share, AFS, NFS or SAMBA.
[0073] The remote file system 35 plays the same function on the remote system 3 as does the file system 25 on the local computer 2 .
[0074] The remote path locations 351 a 351 b have the same function on the remote system 3 as the path location 251 a, b have on the local computer 2 . The same is true for the remote files 3511 a - d.
[0075] Network services 4 are prior art methods to allow the communication and data transfer between a remote data provider 31 and a remote data access service 23 .
Remote Data Access Service 23 :
[0076] This implementation is part of the inventional method and allows to request data from a remote data provider service 31 (see below for details) through a URL notation and associated network services and to write it to a local cache 26 . This is typically a read only procedure from remote and a write to local cache 26 . However, dependent on the specified protocol given to the manager 24 it may also trigger an update of data from the cache back to the specified URL.
File Cache 26 :
[0077] The file cache 26 is part of the local file system and its location is in the local filesystem somehow predefined or configured through manager 24 . Attributes to the caching may be also defined through 2.4 such as interval of caching or actions of the file system listener to either update the cache with files from the remote file system 35 or write created files to the remote file system 35 if so defined.
[0078] A file cache path 261 , and cached files 2611 a,b,c,d are defined as known from prior art.
Remote Data Provider 31 :
[0079] This is a service on the remote computer 3 that waits for remote request through an URL request to provide the requested data of the file system of the server.
[0080] Network Access Mechanism 4 Via URL:
[0081] This provides the communication and data transfer mechanism defined through a given URL and coordinated by service 23 n on the local computer and 31 on the remote computer.
[0082] URL format 2.2d.n is a part of the path specification.
[0083] This shows the URL format now replacing the former path specification to access data via different protocols such as http://, https://, ftp:// and even file://.
[0084] An URL schema or protocol 22 d 1 defines the method to be used to access the data specified via elements 22 d 2 and 22 d 3 , wherein
[0000] URL server 22 d 2 defines the server location holding the data, and
URL data location information 22 d 3 provides the information to access the remote data.
[0085] It is transparent to the user where the data really exists.
[0086] On the server side the services 23 n and 31 are then responsible to map the string into the real data location on the server to bring it to the local file system.
[0087] The inventional Environment Variable Definition Command 22 a with an URL differs from prior art command 22 a in the way that now the specification of an URL is treated in a special way.
[0088] Different implementations may choose respective different ways to trigger a treatment of an environment variable definition if an URL occurs. Command 22 a may create a special indicator in the keyword to identify the treatment such as “$path= . . . ”. There may also be a separate configuration process to identify explicitly the environment variable to be treated in the special way or even strings in the values to be treated special or any combination.
[0089] According to this embodiment, an Environment Variable Manager 24 is extended somehow as described as follows:
[0090] The extended manager 24 will take the pre-defined environment variable definition command 22 a by the environment user service 221 and parse it into environment variable keyword 22 b , file system path 22 c , and 22 d . Those elements will be entered into newly created entries 243 abc of the thus extended table 240 .
[0091] Each of these entries 243 will now be investigated if a remote data access format is found like seen in the command 22 a . If so, then a request will be passed to the inventional version 23 n of the remote data access service in order to cache the referenced file or files in this file location specification to the local cache 26 .
[0092] The entry location of the local cache 26 is then entered into table entries 242 a,b,c.
[0093] Assume that the inventional command 22 a is part of the prior art command, then entries 241 a,b,c are stored in entries 243 a,b,c.
[0094] The inventional environment variables manager 24 , however, will replace entries 241 a,b,c by the corresponding file cache location 262 . If all remote references are replaced within command 22 a , then the new command 22 a containing only references to local file system paths will be stored into entries 242 a,b,c for actual use by the application program 21 and commandshell
[0095] Beside this basic mapping the inventional manager 24 may hold additional configuration values such as default caching intervals and caching location. It may also hold for special remote access specification such as command 22 a specific caching location and caching intervals and other needed attributes for optimized management.
[0096] Typically the specified URL points to a read only location so that only caching from remote to local would be initiated to the inventional version of the remote data access service 23
[0097] If, however, the URL also allows a write function, then additional information for authentication may be available to the inventional manager 24 to initiate then an update request to the inventional service 234 to synchronize the cache to the remote location.
[0098] Extended Environment Variable Table 240 :
[0099] This table 240 has basically the same structure and function as described as for element 240 above. The only differences are that a third column 243 is added to distinguish between the entered value in the new column 243 and the used value in the already existing column 242 . In prior art the used column is always the same as the pre-defined column.
Extended Definition 243 of Environment Variables:
[0100] This will according to this embodiment represent the externally defined value which will then be parsed by manager 24 for remote references of a format such as given by reference sign 22 d 1 , 22 d 2 , or 22 d 3 . Dependent on the given administrative solution to identify the special treatment it will then also parse and format the environment keyword to the conventional expected keyword to be stored and found under entries 241 a,b,c.
[0101] Manager 24 will then initiate the caching of the remote files and add the local file location of the cached files into entry 242 a,b,c so that the application program 21 can access the data defined as remote data transparently with traditional local access methods.
[0102] Based on the functions as described above the inventional method will be described in addition to the foregoing by a control flow description as follows and with reference to FIG. 3 :
[0103] With respect to the objective noted in the end of prior art discussion above instead of using the location information that is pointing to a remote server through the local file system, the access through an URL is implemented herein as follows:
[0104] Before the application is started the environment variable must be set in a step 310 with an appropriate value by issuing command 22 a to the command shell 22 . The command in a concrete example may be “SET $path=c:\appll\lib;protocol://server/path;c:\tools”
[0105] In a next step 315 the command shell will pass the value 22 f to the environment variable user service 221 .
[0106] In a next step 320 the environment variable user service 221 will give the environment variable definition 22 b and 22 f to manager 24 (see FIG. 2 ); in our example “$path=c:\appll\lib;protocol://server/path;c:\tools”
[0107] Manager 24 will store the definition statement into column 243 of table 240 , in a step 325 .
[0108] Manager 24 will then parse out the key and the value in a step 330 and store them into environment variable table 240 in a step 335 . For the key it will get “$path” and for the value “c:\appll\lib;protocol://server/path;c:\tools”
[0109] The key goes into column 241 in step 335 . It may include some reformatting to the expected key value in the traditional format. In the exemplary case the “$” is stripped off and the value stored into entry 241 a is “path”.
[0110] If a decision 240 yields that the key value indicated no special treatment of URL notations, then the parsed value is stored in a step 345 into entry 242 and the work is done.
[0111] If it had the treatment marker—in our case the key starts with a “$”—then the value string is parsed down in a step 350 to identify the path elements which are in the sample case separated by “;”. So the filesystem paths 22 c , 22 dn and 22 e are identified. Each of them is checked if it contains an URL definition such as in the sample case the URL definition 22 dn , leading to a plurality of decisions 355 .
[0112] For each of the detected URLs the following steps will be performed in the YES branch of decision 355 :
[0113] Pass the URL in a step 360 to the remote data access service 23 n which handles the access of the remote data.
[0114] This service 23 n will now forward the request to the remote data provider service 31 located on the remote system 3 , in order to get the files within the URL location from its file system 35 , step 360 .
[0115] An example for such a process is shown next below:
[0116] Example to access data from a CVS library via http
[0000]
See documentation of tool at
http://cvsgrab.sourceforge.net/
Example of data access
cvsgrab -url
http://cvs.apache.org/viewcvs.-
cgi/ant/?only_with_tag=ANT_16BRANCH
[0117] In the present example with the URL http://server.com/path will point to a directory location 351 a.
[0118] Service 23 n gets now all the files from service 31 such as in the example the files 3511 a and 3511 b , step 365 and stores them in a step 370 into the local cache 26 at the location 261 a resulting into the files 2611 a and 2611 b . It may be implemented to optimize this download procedure by finding out that files are still in sync or identify those who changed.
[0119] The returned cache path 261 a is now used in a step 375 to replace the URL definition in the environment variable value 22 f . In the example “http://server.com/path” gets replaced by “d:\cache\srv\pathx”.
[0120] Dependent on the implementation the environment variables manager 24 may now trigger an update 380 of the cache through the service 23 n in pre-defined intervals. This is an endless loop that also gets started with each startup of the local computer.
[0121] If a decision 385 yields that all detected URLs are processed the value 22 f of the environment variable under analysis will have no URLs but instead will comprise corresponding local file paths. So the string “c:\appll\lib; http://server.com/path;c:\tools” is transformed to “c:\appll\lib;d:\cache\srv\pathx;c:\tools”. This string becomes now the environment variable for use and will therefore be stored into entry 242 b , see step 395 .
[0000]
...
...
path
c:\appl1\lib;d:\cache\srv\
$path= c:\appl1\lib;
pathx;c:\tools
http://server.com/path;
c:\tools
...
...
[0122] If URLs get redefined, i.e. modified or deleted from the value section 22 f , then the old URL will be “cleaned up” which means the update request in step 380 above gets stopped and the related cache gets deleted.
[0123] In the NO-branch of decision 385 control is fed back to step 360 in order to re-enter the loop body for processing the next URL.
[0124] The control flow used in the inventional method for Retrieving environment variable content by the application program 21 follows the scheme as given in FIGS. 3A and 3B , because the application program 21 has the same interface to manager 24 and gets only path location pointing to the local file system.
[0125] In particular, an application running on the local computer system can be invoked with parameters to define its behaviour each time on invocation. However, it is convenient to provide standard invocation parameters sometime through environment variables so that the system can read them out after invocation. For this reason each application has a defined set of environment variables to be set before invocation which it will used to get their content for further processing.
[0126] The application issues one of the methods described above. So with the present example the application program calls for the value of “path”.
[0127] It now gets back the value of the environment variable. In the sample case the value is c:\appll\lib; d:\program2\includes;c:\tools.
[0128] The same holds true for the control flow which is performed by the application program 21 when it access the file data, because the application 21 only gets local file system location formats from manager 24 and does not ask for the real location of the data, per se only reachable via URL request.
[0129] It should be noted that this is in some sense independent of the actual usage of the environment variable. The application must just somehow get a string with the file paths to search for. And this could be either through environment variables or parameter passing or other methods or even any combination to get such a search path. The application 21 is typically written that it has no knowledge where the data actually resides. It just assumes that it needs access to the local file system component and does not have to provide network services by itself.
[0130] With the given search path the application is now looking for a file to use and issues a service by its own or some existing service to access each path in sequence given in the search path and to test if the file exist. Note that for the application it is transparent if the file is on a remote server or not because this is handled through the local filesystem.
[0131] If the file is found then the path is found and the content of the file can be read or the file can be treated in the way the application wants.
[0132] Finally, some sample implementations are given for the purpose of completeness of the disclosure:
[0133] An example to access files from a http repository into a local cache is given in FIG. 4 .
[0134] FIG. 5 shows a Java code sample for an environment variable access service 211 .
[0135] FIG. 6 shows a standard API for accessing environment variables.
[0136] An environment variable user service 221 is given by the following code sample for a Windows command shell program:
[0000] Create environment variable entries:
[0000]
SET INCLUDE=C:\Program Files\ObjREXX\API
SET TEMID=wuclientde
SET LIB=C:\Program Files\ObjREXX\API
[0137] A sample for listing an environment variable in command shell is:
SET INCLUDE
[0138] The invention can take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment containing both hardware and software elements. In a preferred embodiment, the invention is implemented in software, which includes but is not limited to firmware, resident software, microcode, etc.
[0139] Furthermore, the invention can take the form of a computer program product accessible from a computer-usable or computer-readable medium providing program code for use by or in connection with a computer or any instruction execution system. For the purposes of this description, a computer-usable or computer readable medium can be any apparatus that can contain, store, communicate, propagate, or transport the program for use by or in connection with the instruction execution system, apparatus, or device.
[0140] The medium can be an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system (or apparatus or device) or a propagation medium. Examples of a computer-readable medium include a semiconductor or solid state memory, magnetic tape, a removable computer diskette, a random access memory (RAM), a read-only memory (ROM), a rigid magnetic disk and an optical disk. Current examples of optical disks include compact disk-read only memory (CD-ROM), compact disk-read/write (CD-R/W) and DVD.
[0141] A data processing system suitable for storing and/or executing program code will include at least one processor coupled directly or indirectly to memory elements through a system bus. The memory elements can include local memory employed during actual execution of the program code, bulk storage, and cache memories which provide temporary storage of at least some program code in order to reduce the number of times code must be retrieved from bulk storage during execution.
[0142] Input/output or I/O devices (including but not limited to keyboards, displays, pointing devices, etc.) can be coupled to the system either directly or through intervening I/O controllers.
[0143] Network adapters may also be coupled to the system to enable the data processing system to become coupled to other data processing systems or remote printers or storage devices through intervening private or public networks. Modems, cable modem and Ethernet cards are just a few of the currently available types of network adapters. | The present invention relates to the field of network computing. In particular, it relates to a method and respective system for providing access for an application program to remote resources located in an electronic computer network, wherein said application program is implemented on a computer residing in said network. A mechanism is provided to enable local running application programs to dynamically use URL-addressed data in the Internet or an Intranet without any change in their program source code. | 6 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation application of U.S. patent application Ser. No. 12/495,558, filed Jun. 30, 2009.
[0002] This document relates to the subject matter of a joint research agreement between Intermolecular, Inc. and Elpida Memory, Inc.
FIELD OF THE INVENTION
[0003] The present invention relates generally to dielectric materials. More specifically, techniques for depositing high-K dielectrics are described.
BACKGROUND OF THE INVENTION
[0004] Semiconductor memories (e.g. dynamic random access memory (DRAM)) can include memory cells that have a capacitor to store charge. The capacitor is typically a metal-insulator-metal (MIM) structure in which the insulator stores the charge for the cell. The state of the memory cell can be changed (e.g. from 0 to 1 or 1 to 0) by charging or discharging the capacitor.
[0005] It is desirable to reduce the size of individual memory cells to increase memory density thereby increasing potential memory storage. One way to reduce the size of individual memory cells is to increase the dielectric constant (K) of the insulator materials in the capacitors. A material with a higher dielectric constant can store more charge per unit volume, thereby reducing the amount of material needed to achieve a desired amount of charge.
[0006] Several materials have high dielectric constants. For example, titanium oxide potentially has a dielectric constant of over 90. However, different crystal phases of titanium oxide have different dielectric constants, and titanium oxide layers often have dielectric constants much lower than is desirable. Thus, what is needed are techniques for increasing the dielectric constant of deposited layers.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] Various embodiments of the invention are disclosed in the following detailed description and the accompanying drawings:
[0008] FIG. 1 is a flowchart illustrating a process for increasing a dielectric constant of a dielectric layer used for semiconductor memory;
[0009] FIG. 2 illustrates a memory cell including a capacitor having a metal-insulator-metal (MIM) structure;
[0010] FIGS. 3A-3D illustrate the formation of an MIM capacitor using techniques to increase the dielectric constant of an insulating layer;
[0011] FIG. 4 is a flowchart describing a process for forming a capacitor;
[0012] FIG. 5A illustrates the reduction of the contact angle of a platinum electrode when subjected to oxygen plasma treatment;
[0013] FIG. 5B is a graph that illustrates the growth of ALD layers deposited on platinum;
[0014] FIG. 5C is an X-Ray Diffraction (XRD) graph illustrating the deposition of titanium oxide on platinum electrodes using oxygen plasma treatments discussed herein;
[0015] FIG. 6A is an XRD graph showing the crystal orientations of films deposited using certain PVD conditions; and
[0016] FIG. 6B is a contour plot showing that the XRD peak height ratio between rutile (211) and anatase (211) increases when titanium dioxide is deposited on a platinum electrode deposited with a higher oxygen (O 2 ) partial pressure in the working gas and with a higher pedestal temperature. These conditions also give platinum with a [111] orientation.
DETAILED DESCRIPTION
[0017] A detailed description of one or more embodiments is provided below along with accompanying figures. The detailed description is provided in connection with such embodiments, but is not limited to any particular example. The scope is limited only by the claims and numerous alternatives, modifications, and equivalents are encompassed. Numerous specific details are set forth in the following description in order to provide a thorough understanding. These details are provided for the purpose of example and the described techniques may be practiced according to the claims without some or all of these specific details. For the purpose of clarity, technical material that is known in the technical fields related to the embodiments has not been described in detail to avoid unnecessarily obscuring the description.
[0018] According to various embodiments, techniques for forming high-dielectric constant (high-K) dielectric layers are described. The dielectric layer can be used as part of a capacitor for a memory cell, for example. The dielectric layer can be, for example, titanium oxide, which has a relatively higher-K crystal phase (rutile) and a relatively lower-K crystal phase (anatase). The techniques described herein can be used to deposit more rutile relative to the amount of anatase that is deposited. Rutile growth can be encouraged by using an oxygen plasma treatment on the electrode on which the titanium oxide is to be deposited. Additionally, rutile growth can be promoted by varying physical vapor deposition (PVD) parameters for the deposition of an electrode on which the titanium oxide is to be deposited. In some embodiments, rutile growth can be promoted by depositing titanium oxide on a platinum electrode and increasing the pedestal temperature and the oxygen partial pressure of the working gas during deposition of the electrode.
I. Memory Cells
A. High-K Dielectrics
[0019] A capacitor can be used to store a bit of memory. For example, dynamic random access memory (DRAM) cells include a metal-insulator-metal (MIM) capacitor that can have a different value (e.g., 0 or 1) depending on the amount of charge stored. As DRAM arrays become smaller and smaller, a need has arisen for high-K dielectrics that can be used with DRAM capacitors. Higher-K materials can store more charge in a smaller volume, and therefore are desirable for reducing memory cell size.
[0020] Titanium Oxide (TiO 2 ) is one high-K material. Titanium oxide can have multiple crystal phases which have different dielectric constants. Two known crystal phases of titanium oxide are anatase and rutile. Anatase is relatively lower-K (K˜40), while rutile has a much higher dielectric constant (K˜90). It is therefore desirable to promote the formation of rutile, even in films that may also contain anatase, to increase the dielectric constant of deposited films and therefore the ability to use smaller features in semiconductor devices.
B. Process for Increasing Dielectric Constant of Deposited Metal Oxides
[0021] FIG. 1 is a flowchart illustrating a process 100 for increasing a dielectric constant of a dielectric layer used for semiconductor memory. For example, the dielectric layer can be used in a metal-insulator-metal (MIM) capacitor that is part of a semiconductor memory cell such as dynamic random access memory (DRAM) (see e.g. FIG. 2 ).
[0022] In operation 102 , a first electrode is deposited on a substrate. The electrode can be, for example, noble or near-noble metal such as platinum or ruthenium. In other embodiments, the electrode can be a metal or compound having a relatively high work function (e.g. greater than 5 eV). Such materials are used for semiconductor memories because of their advantageous electrical characteristics. For example, platinum has a high work function (˜5.65 electron volts), which can reduce leakage in capacitors, which in turn reduces the refresh rate of a memory using the capacitors. In some embodiments, PVD process conditions for depositing the first electrode can be changed to increase the amount of rutile in a titanium oxide layer deposited on the first electrode.
[0023] In operation 104 , an oxygen plasma treatment is applied to the first electrode to reduce the contact angle of the surface of the electrode. As is explained further in the discussion of FIG. 5A , oxygen plasma can be use to reduce the contact angle of typically hydrophobic noble metals such as platinum, which can therefore be used to increase adsorption of precursors used to deposit metal oxides thereon. Additionally, as will be explained regarding FIG. 5C , the plasma treatment changes the surface energy of the electrode thereby promoting the growth of rutile titanium oxide on the treated electrode, and increasing the dielectric constant of a titanium oxide layer deposited on the first electrode.
[0024] In operation 106 , a titanium oxide layer is deposited on the first electrode using at least one of chemical vapor deposition (CVD) and atomic layer deposition (ALD). CVD and ALD are vapor-based deposition techniques that use precursors to react with an oxidant in the gas mixture or on electrode surface to form a layer of material (e.g. a titanium oxide layer). In further operations, a capacitor can be formed by forming an additional electrode over the titanium oxide layer.
C. Memory Cell Structure
[0025] FIG. 2 illustrates a memory cell 200 including a capacitor having a metal-insulator-metal (MIM) structure. The memory cell 200 is one of several possible configurations that can be formed utilizing the high-K dielectrics described herein. The memory cell 200 includes a capacitor 202 having an MIM structure, although other layers (e.g., multiple insulating or metal layers) can be included. For example, the capacitor 202 may be a metal-insulator-insulator-metal (MIIM) or a metal-insulator-metal-insulator-metal (MIMIM) structure.
[0026] The capacitor 202 includes two conductive electrodes 204 and 206 , and an insulating layer 208 (a dielectric). The electrodes 204 and 206 can be noble, near-noble or non-noble metals (for example platinum or ruthenium) that, for example, have a high work function thus promote lower leakage, and the insulating layer 208 is a high-K dielectric such as titanium oxide or doped titanium oxide. In other embodiments, the electrodes can be any material that is hydrophobic or that inhibits the formation of oxides thereon. The capacitor 202 is surrounded by interlayer dielectrics (ILDs) 210 that can be insulating materials such as silicon dioxide, silicon nitride, or low-K dielectrics. The capacitor 202 is shown having a cylinder structure, although other capacitor configurations such as pedestal/pillar structures or crown structures can also be used.
[0027] The capacitor is connected to contacts 212 and 214 , which can be used to apply voltage across the MIM 202 to maintain charge on the memory cell 200 and to change the memory state of the cell 200 . The contact 214 is attached to a memory cell transistor 216 which can be used to select the memory cell 200 for read/write access. It is understood that the cell 200 is an example of memory cells that could be used with the high-K dielectrics described herein, and that other structures and configurations can also be used.
II. Electrode Processing and High-K Dielectric Deposition
A. Electrode Processing and Device Formation
[0028] FIGS. 3A-3D illustrate the formation of an MIM capacitor using techniques to increase the dielectric constant of a titanium oxide layer. FIG. 4 is a flowchart describing a process 400 for forming a capacitor 300 .
[0029] In operation 402 , a substrate 302 is provided. The substrate may be any appropriate substrate, such as a silicon-based substrate, and may include conductive portions such as interconnects (bit lines, word lines) or contact plugs such as those shown in FIG. 2 . For example, the substrate 302 may include interlayer dielectrics 210 and a contact 214 .
[0030] In operation 404 , a first electrode 304 is deposited on the substrate 302 . The first electrode 304 may be a noble, near-noble, or non-noble material, for example platinum or ruthenium, and can be deposited using any appropriate technique, such as CVD, ALD, or PVD. In some embodiments, (see operation 405 ), the first electrode 304 can be platinum deposited using certain PVD processing parameters so that a desired texture of the electrode is achieved (see FIGS. 6A and 6B ) to increase the amount of rutile deposited on the first electrode. In other embodiments, the first electrode 304 may be any conductive material that is hydrophobic and inhibits the formation of oxides thereon. FIG. 3A illustrates the first electrode 304 deposited on the substrate 302 . The first electrode 304 may be, for example, the electrode 206 of the memory cell 200 .
[0031] In operation 405 , when the electrode 304 is deposited, the electrode 304 can be optionally textured to promote the growth of rutile titanium oxide insulator on the electrode 304 . Rutile titanium oxide is desirable because it has a high dielectric constant (K˜90) relative to the anatase crystal phase of titanium oxide (K˜40). It can also be desirable to increase the proportion of rutile titanium oxide compared to anatase.
[0032] Rutile has a tetragonal crystal structure whose growth can be encouraged by using vapor-based deposition techniques (e.g. ALD, CVD) to deposit titanium oxide on electrodes having similar crystal structures or similar lattice parameters at their interface. As is described in more detail in the discussion regarding FIGS. 6A and 6B , a platinum electrode having a [111] orientation may provide a good template for rutile titanium oxide. In some embodiments, the [111] platinum orientation can be encouraged by varying certain PVD processing parameters, such as working gas mixture and pedestal temperature. For example, in order to deposit platinum having a [111] orientation, a deposition process using a working gas mixture having an oxygen partial pressure of greater than 10 percent at pedestal temperature of 300° C. can be used.
[0033] In operation 406 , the first electrode 304 is treated using an oxygen plasma treatment 306 , which is shown in FIG. 3B . The plasma treatment 306 can be applied using a plasma applicator 308 such as a high-vacuum plasma system or an atmospheric plasma application. Any type of plasma treatment can be used to improve ALD or CVD nucleation. For example, samples were prepared using both high-density radio frequency (RF)-based plasma (using a preclean chamber of a PVD tool) and atmospheric plasmas (using a handheld plasma application tool). The high-density plasma could be formed from oxygen or oxygen and another gas, with powers from 500 W to 10 kW, and pressures from 10-15 mTorr, for example. These two plasma applications span the range from high-quality to low-quality applications, but still produce high-K metal oxide layers. This indicates that the important quality of the plasma is that the oxygen radical species change the nature of the surface of the electrode and change the surface energy regardless of the method of plasma application. It is believed that this modification promotes the growth of rutile titanium oxide.
[0034] In operation 408 , a titanium oxide layer 310 is deposited over the first electrode 304 , which is shown in FIG. 3C . The titanium oxide layer 310 can also be doped with another insulating layer, for example to form a yttrium doped titanium oxide layer or an aluminum doped titanium oxide layer. In some examples, yttrium oxide concentrations can be from 1-5 atomic percent and aluminum oxide concentrations can be from 1-20 atomic percent.
[0035] The titanium oxide layer 310 can be deposited using either CVD or ALD, and can be deposited from precursors such as Titanium Tetraisopropoxide (TTIP), Tetrakis Dimethylamino Titanium (TDMAT), Tetrakis Diethylamido Titanium (TDEAT), or tetrakis-ethylmethyl-amido titanium (TEMAT). With ALD depositions, the oxidizing reagent can be ozone, water vapor, or oxygen. The thickness of the layer can be any desired thickness, for example from 10-1000 Å.
[0036] The plasma treatment of the first electrode 304 helps to promote the growth of rutile titanium oxide, which has higher dielectric constant than anatase. The plasma treatment promotes the deposition of a smoother oxide layer. It is also believed that the plasma treatment changes the surface energy of the electrode 304 , which encourages the growth of rutile. As is described in the discussion regarding FIG. 5C , the oxygen plasma treatment can help suppress the formation of anatase and promote the formation of rutile.
[0037] In operation 410 , a second electrode 312 (e.g. the electrode 204 ) is deposited, and the capacitor formation is completed. After the second electrode is deposited, other layers, such as the contact 212 can be deposited thereon. FIG. 3D illustrates the completed capacitor 300 .
[0038] In some embodiments, the titanium oxide layer can be thermally treated, for example by annealing, either before or after the second electrode 312 is deposited. For example, the titanium oxide layer can be annealed using a rapid thermal oxidation (RTO) of approximately 600° C. or greater. The thermal treatment, it is believed, can cause or enhance the formation of rutile in the titanium oxide layer.
B. Experimental and Sample Data
[0039] FIG. 5A illustrates the reduction of the contact angle of a platinum electrode when subjected to oxygen plasma treatment. As shown in the graph 500 , the platinum substrate as deposited, before treatment 502 , has a contact angle of at least 50°, indicating a hydrophobic surface that may inhibit ALD nucleation. After a one hour oxygen plasma treatment 504 , the contact angle drops to approximately 0°, indicating an extremely hydrophilic surface that promotes ALD nucleation. Three hours following the completion of the treatment, although the contact angle increases 506 , it is still lower than that as deposited Pt, which can, for ALD process, significantly reduce nucleation delay (see FIG. 5B ).
[0040] Rapid thermal oxidation (RTO) is another treatment that can be used to lower the contact angle of electrodes. For example, a bare platinum electrode surface was optimized post RTO at 700° C. for ten minutes 508 , lowering the contact angle to below 20°. However, the plasma treatment 504 reduces the contact angle much further, and therefore better promotes nucleation of ALD precursors.
[0041] As-deposited platinum and other noble metals hinder ALD nucleation, which can lead to a nucleation delay. FIG. 5B is a graph that illustrates the growth of ALD layers deposited on platinum. The graph 520 plots thickness as a function of a number of ALD cycles. A plot 522 illustrates the theoretical growth of a metal oxide layer deposited on platinum that has been treated using oxygen plasma, and a plot 524 illustrates the theoretical growth of a metal oxide layer deposited on platinum that has not been so treated. The nucleation delay 526 of the plot 522 and the nucleation delay 528 of the plot 524 are periods of time over which layer growth is retarded because of poor nucleation on the platinum surface. Typically, the first cycles of deposition for untreated platinum or ruthenium substrates can suffer from the reduction in deposition rate as precursors may not adsorb to the platinum surface as readily as they do to already deposited layers of metal oxide since the already-deposited layers are more receptive to ALD nucleation.
[0042] As can be seen, in theory the nucleation delay 526 is much shorter than the nucleation delay 528 , illustrating another potential benefit of the oxygen plasma treatment. Additionally, since in theory fewer cycles are required to deposit the layer, less precursor is used, which reduces waste and therefore costs. In some embodiments, the nucleation delay 526 can be eliminated or almost eliminated.
[0043] FIG. 5C is an X-Ray Diffraction (XRD) graph 540 illustrating the titanium oxide layer deposited on platinum electrode using oxygen plasma treatments discussed herein. XRD can be used to determine the existence of different crystal phases in a sample. Each crystallized structure has its signature X-ray diffraction angles—for example, platinum crystal shows a peak at approximately 67.5° for its (220) planes' diffraction if copper is used as the X-ray source.
[0044] Plots 542 and 546 represent titanium oxide layers deposited on oxygen plasma treated platinum bottom electrodes. The titanium oxide layers were deposited using ALD with a titanium tetraisopropoxide (TTIP) precursor. The plot 542 represents a sample that has been thermally treated (using rapid thermal anneal with O 2 (RTO)) at 700° C. for 10 minutes after the deposition of the titanium oxide layer, and plot 546 represents a sample that has not been thermally treated. Plots 544 and 548 represent samples that were deposited without treating the platinum electrode; plot 544 represents a sample that was thermally oxidized, and plot 548 represents a sample that was not thermally oxidized.
[0045] The plasma-treated samples 542 and 546 and the thermally oxidized but untreated sample 544 show rutile (211) peaks 550 at 54.3°. The rutile peak from plasma-treated sample 542 is stronger than the rutile peak from untreated sample 544 . The untreated sample 548 shows no rutile peak, and shows an anatase (105) peak 552 at 53.9°. Therefore, the plasma treatment of the platinum appears to increase the amount of rutile in the titanium oxide layer.
[0046] All samples show anatase (101) peaks 554 at 25.3°, the intensity which increases with thermal oxidation and which is unaffected by plasma treatment. Additionally, anatase (200) peaks 556 at 48.1° are present in the thermally oxidized samples 542 and 544 , but are unaffected by plasma treatment. Other peaks shown in FIG. 5C include platinum (111) peaks 560 at 39.8°, platinum (200) peaks 562 at 46.2°, and platinum (220) peaks 564 at 67.5°.
[0047] Plasma treatment of platinum electrodes thereby promotes the growth of rutile titanium dioxide. Samples that were formed without plasma treatment showed substantially no rutile formation. Additionally, the dielectric constant of the titanium dioxide layer may increase from approximately 40 to 50-60. Additionally, although data for platinum is shown here, oxygen plasma treatment should encourage the growth of rutile on other noble, near-noble, or non-noble electrodes such as ruthenium.
III. Electrode Texturing
[0048] Depositing titanium oxide on untreated platinum typically results in the deposition of relatively low-K anatase. Described below are techniques for promoting the deposition of rutile by altering process conditions for PVD platinum deposition to change the texture (crystal orientation) of the platinum electrode. Depositing a textured platinum electrode having lattice parameters in the surface plane that match the lattice parameters of rutile titanium oxide can promote the growth of rutile titanium oxide and increase the K-value of the deposited dielectric. In this way, the platinum electrode can be used as a template. A platinum electrode having strong [111] crystal orientation can be used as a template for rutile deposition. As is described further below, the [111] orientation can be encouraged by using a high pedestal temperature (i.e. greater than 250° C.) and a working gas with a high oxygen partial pressure (e.g. greater than 10 percent). The working gas can include, for example, argon (or another inert gas) and oxygen.
[0049] FIG. 6A is an XRD graph showing the crystal orientations of films deposited using certain PVD conditions. FIG. 6B is a contour plot showing that the proportion of rutile to anatase increases when titanium oxide is deposited on an electrode that was deposited using PVD with a higher oxygen (O 2 ) partial pressure in the working gas and with a higher pedestal temperature. These conditions also give platinum with a [111] orientation. In addition, texturing can be combined with plasma treatments, described above, to further increase the film's dielectric constant.
[0050] Various parameters of the PVD deposition of platinum can be used to texture the electrode: changing the pedestal temperature and changing the mixture of the working gas have been shown to affect platinum texture. The plots 602 - 606 of FIG. 6A show the XRD plots of platinum electrodes deposited using varying conditions. The plot 602 represents a platinum sample deposited at high pedestal temperature (250-300° C., for example) in an argon/oxygen working gas mixture. The plot 604 represents a platinum sample deposited with a pedestal temperature of approximately 20° C. and an argon/oxygen working gas. The plot 606 represents a platinum sample that is deposited using a high pedestal temperature (250-300° C.) and a working gas having a high oxygen partial pressure, for example greater than 10%. Sputtering power was also investigated as a variable for altering the platinum texture, but was shown to have a minor effect on texture. The plots 602 and 604 were deposited at 50 watts of power.
[0051] The [220] orientation is indicated by the peaks 608 at 67.5°, the [200] orientation is indicated by the peaks at 46.2°, and the [111] orientation of platinum is indicated by the peaks 612 at 39.8°. High oxygen partial pressure and high pedestal temperature (e.g., greater than 10% and greater than 250° C.) encourage formation of the [111] orientation as indicated by the peaks 612 . The sample represented by the plot 606 has a strong (111) peak and a weak (220) peak, versus the sample represented by the plot 604 , which has both a strong (220) peak and a strong (111) peak. The sample represented by the plot 606 therefore has a higher proportion of [111] platinum. When titanium oxide was deposited on the samples represented by the plots 604 and 606 , using TTIP and ozone as ALD reagents, and using a 600° C. RTO, a rutile (211) peak was found on the sample represented by the plot 606 . Therefore, rutile [211] has been shown to form on platinum deposited using PVD with oxygen partial pressures exceeding 10% and pedestal temperatures exceeding 250° C. Further, as is shown in FIG. 6B , rutile is more likely to form under these conditions.
[0052] FIG. 6B is a contour plot 650 showing the XRD peak ratio between rutile (211) and anatase (211) in a sample as a function of PVD working gas oxygen partial pressure and pedestal temperature. The section 652 corresponds to higher deposition temperatures and higher oxygen partial pressures that result in a rutile (211) to anatase (211) ratio of greater than 0.875. Therefore, increasing the pedestal temperature and increasing the oxygen partial pressure of the working gas have been shown to increase the amount of rutile deposited. For example, a pedestal temperature of greater than 200° C. and an oxygen partial pressure of more than 10% can produce desirable amounts of rutile. Alternatively, higher temperatures (e.g., 250° C., or 300° C.) or higher oxygen partial pressures (e.g. 15%, 20%, 30%, 40% or greater) increase the likelihood of the deposition of rutile on the platinum electrode.
[0053] In some embodiments, for example, the pedestal temperature can be greater than 200° C., greater than 250° C., greater than 300° C., between 200 and 300° C., between 250 and 300° C., between 250 and 400° C., etc. In some embodiments, for example, the working gas for the PVD process can include oxygen (e.g. can be an argon/oxygen mixture), and the oxygen partial pressure can be greater than 10%, greater than 15%, greater than 20%, greater than 30%, greater than 40%, between 10% and 20%, between 10% and 15%, between 15% and 20%, between 15% and 30%, etc.
[0054] Although the foregoing examples have been described in some detail for purposes of clarity of understanding, the invention is not limited to the details provided. There are many alternative ways of implementing the invention. The disclosed examples are illustrative and not restrictive. | Methods for depositing high-K dielectrics are described, including depositing a first electrode on a substrate, wherein the first electrode is chosen from the group consisting of platinum and ruthenium, applying an oxygen plasma treatment to the exposed metal to reduce the contact angle of a surface of the metal, and depositing a titanium oxide layer on the exposed metal using at least one of a chemical vapor deposition process and an atomic layer deposition process, wherein the titanium oxide layer comprises at least a portion rutile titanium oxide. | 7 |
FIELD OF THE INVENTION
The present invention relates to power supply circuits, and particularly to a power supply circuit with a stand-by control circuit and an energy storage circuit.
GENERAL BACKGROUND
FIG. 7 is a schematic view of a conventional power supply circuit. The power supply circuit 1 includes a first input terminal 2 , a second input terminal 3 , a relay 4 , a main power supply 5 , an assistant power supply 6 , a microprocessor 7 , and a switch 8 . The assistant power supply 6 includes a transformer 9 and a commutating and filter circuit (not labeled).
The first input terminal 2 is connected to the main power supply 5 , and the second input terminal 3 is connected to the main power supply 5 via the relay 4 . The main power supply 5 is connected to a load (not shown). The transformer 9 includes a primary winding (not labeled) and a secondary winding (not labeled). The primary winding includes two terminals (not labeled). One of the terminals of the primary winding is connected to the first input terminal 2 , and the other terminal is connected to the second input terminal 3 . The secondary winding is connected to the microprocessor 7 via the commutating and filter circuit. The relay 4 includes an inductance coil (not labeled), and the inductance coil includes two terminals (not labeled). One of the terminals of the inductance coil is connected to the microprocessor 7 , and the other terminal is connected to ground. The microprocessor 7 is connected to ground via the switch 8 .
An alternating current (AC) voltage is inputted into the assistant power supply 6 and converted into a direct current (DC) voltage by the transformer 9 and the commutating and filter circuit. The DC voltage is supplied to the microprocessor 7 to enable the microprocessor 7 to function.
When a user presses the switch 8 , the switch 8 correspondingly generates a first pulse signal. The microprocessor 7 receives the first pulse signal and correspondingly outputs a first control signal to turn on the relay 4 . The AC voltage is inputted into the main power supply 5 via the first input terminal 2 , the second input terminal 3 , and the relay 4 . The main power supply 5 converts the AC voltage into required voltages to supply the load.
When the user presses the switch 8 again, the switch 8 correspondingly generates a second pulse signal. The microprocessor 7 receives the second pulse signal and correspondingly outputs a second control signal to turn off the relay 4 . The main power supply 5 outputs no voltage, and the load stops operating correspondingly. That is, the power supply circuit 2 is in a stand-by state.
Although the power supply circuit 2 is in the stand-by state, the AC voltage is still inputted into the assistant power supply 6 . The DC voltage outputted from the assistant power supply 6 is still supplied to the microprocessor 7 . That is, when the power supply circuit 2 is in the stand-by state, energy consumption is large.
What is needed, therefore, is a power supply circuit that can overcome the above-described deficiencies.
SUMMARY
A power supply circuit configured for supplying power for a load includes: a main power supply configured for converting a received voltage into a required direct current voltage; a microprocessor; a stand-by control circuit configured for controlling the main power supply; an energy storage circuit configured for supplying power for the stand-by control circuit. When the load stops operating, the microprocessor outputs a control signal to the stand-by control circuit, the stand-by control circuit outputs a corresponding control signal to turn off the main power supply. In response to when the load starts operating, the stand-by control circuit outputs a corresponding control signal to turn on the main power supply, and the main power supply charges the energy storage circuit.
Other novel features and advantages will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic view of a power supply circuit according to a first embodiment of the present disclosure, the power supply circuit including a voltage conversion circuit, a commutating and filter circuit, a stand-by pilot circuit, an energy storage circuit, a main power supply, a stand-by control circuit, a microprocessor, and a stand-by detecting circuit.
FIG. 2 is a circuit diagram of one embodiment of the main power supply of FIG. 1 .
FIG. 3 is a circuit diagram of one embodiment of the voltage conversion circuit and the energy storage circuit of FIG. 1 .
FIG. 4 is a circuit diagram of one embodiment of the stand-by pilot circuit of FIG. 1 .
FIG. 5 is a circuit diagram of one embodiment of the stand-by control circuit of FIG. 1 .
FIG. 6 is a schematic view of a power supply circuit according to a second embodiment of the present disclosure.
FIG. 7 is a schematic view of a conventional power supply circuit.
DETAILED DESCRIPTION
Reference will now be made to the drawings to describe certain inventive embodiments of the present disclosure in detail.
FIG. 1 is a schematic view of a power supply circuit 20 according to a first embodiment of the present disclosure. In one embodiment, the power supply circuit 20 includes a first input terminal 211 , a second input terminal 212 , a voltage conversion circuit 22 , a commutating and filter circuit 23 , a stand-by pilot circuit 24 , an energy storage circuit 25 , a main power supply 26 , a stand-by control circuit 27 , a microprocessor 28 , and a stand-by detecting circuit 29 .
An AC voltage is inputted into the commutating and filter circuit 23 via the first input terminal 211 and the second input terminal 212 . The commutating and filter circuit 23 converts the AC voltage into a DC voltage. The commutating and filter circuit 23 includes an output terminal 231 . The DC voltage is supplied to the main power supply 26 via the output terminal 231 . The AC voltage is also supplied to the voltage conversion circuit 22 via the first input terminal 211 and the second input terminal 212 .
The main power supply 26 converts the DC voltage into required DC voltages for a device employing the power supply circuit 20 . In one embodiment, the main power supply may convert the DC voltage into, for example, 26V and 5V. In one embodiment, the main power supply 26 includes a first output terminal 260 , a second output terminal 261 , and a third output terminal 262 . The main power supply 26 supplies DC power for the microprocessor 28 via the first output terminal 260 and the second output terminal 261 , and supplies DC power for the voltage conversion circuit 22 via the first output terminal 260 and the third output terminal 262 .
The voltage conversion circuit 22 includes an output terminal 221 . The voltage conversion circuit 22 supplies DC power for the stand-by pilot circuit 24 and the energy storage circuit 25 via the output terminal 221 .
The stand-by pilot circuit 24 receives the DC voltage from the first output terminal 260 of the main power supply 26 and displays operation conditions of the main power supply 26 . The operation conditions of the main power supply 26 includes a stand-by condition, an operating normally condition, and so on.
The energy storage circuit 25 includes an output terminal 251 . The energy storage circuit 25 supplies power for the stand-by control circuit 27 via the output terminal 251 .
The stand-by detecting circuit 29 includes an input terminal 291 , a first output terminal 292 , and a second output terminal 293 . The stand-by detecting circuit 29 detects operation conditions of a load (not shown) via the input terminal 291 , and outputs correspondingly control signals to the microprocessor 28 via the first output terminal 292 and the stand-by control circuit 27 via the second output terminal 293 . The load can be a liquid crystal display panel for example.
The stand-by control circuit 27 includes a first output terminal 271 and a second output terminal 272 . The stand-by control circuit 27 outputs control signals to control the main power supply 26 via the first output terminal 271 , and outputs control signals to control the microprocessor 28 via the second output terminal 272 .
The microprocessor 28 includes a first output terminal 281 , a second output terminal 282 , and a third output terminal 283 . The microprocessor 28 outputs control signals to the stand-by control circuit 27 via the first output terminal 281 and the second output terminal 282 , and outputs control signals to the load via the third output terminal 283 .
FIG. 2 is a circuit diagram of one embodiment of the main power supply 26 of FIG. 1 . In one embodiment, the main power supply 26 includes a transformer 263 , a switch control circuit 264 , a transistor 265 , and a feedback circuit 266 .
The transformer 263 includes a primary winding 267 and a secondary winding 268 . The primary winding 267 includes two terminals (not labeled). One of the terminals of the primary winding 267 is connected to the output terminal 231 of the commutating and filter circuit 23 , and is also connected to the switch control circuit 264 via a resistor (not labeled). Another terminal of the primary winding 267 is connected to a source electrode (not labeled) of the transistor 265 . The secondary winding 268 includes two terminals (not labeled) and a tap (not labeled). One of the terminals of the secondary winding 268 is connected to the first output terminal 260 of the main power supply 26 via a commutating and filter circuit (not labeled), and another terminal is connected to ground. The tap of the secondary winding 268 is connected to the second output terminal 261 of the main power supply 26 via another commutating and filter circuit (not labeled).
The switch control circuit 264 is connected to the first output terminal 271 of the stand-by control circuit 27 . The switch control circuit 264 is also connected to a gate electrode (not labeled) of the transistor 265 . A drain electrode (not labeled) of the transistor 265 is connected to ground via a resistor (not labeled). The feedback circuit 266 is connected between the second output terminal 261 of the main power supply 26 and the switch control circuit 264 .
FIG. 3 is a circuit diagram of one embodiment of the voltage conversion circuit 22 and the energy storage circuit 25 of FIG. 1 . The energy storage circuit 25 includes an energy storage capacitor 250 . The energy storage capacitor 250 is connected between the output terminal 251 and ground. In one embodiment, the voltage conversion circuit 22 includes a large voltage conversion circuit 222 , a first small voltage conversion circuit 223 , a second small voltage conversion circuit 224 , and a third small voltage conversion circuit 225 .
The large voltage conversion circuit 222 includes a diode (not labeled). An anode of the diode is connected to the first output terminal 260 of the main power supply 26 , and a cathode of the diode is connected to the output terminal 221 of the voltage conversion circuit 22 .
The first small voltage conversion circuit 223 is connected between the first input terminal 211 of the power supply circuit 20 and the output terminal 221 of the voltage conversion circuit 22 . The second small voltage conversion circuit 224 is connected between the second input terminal 212 of the power supply circuit 20 and the output terminal 221 of the voltage conversion circuit 22 . The third small voltage conversion circuit 225 is connected between the third output terminal 262 of the main power supply 26 and the output terminal 221 of the voltage conversion circuit 22 . The first small voltage conversion circuit 223 , the second small voltage conversion circuit 224 , and the third small voltage conversion circuit 225 may have the same structure.
Each of the small voltage conversion circuits 223 , 224 , 225 includes a first capacitor 2231 , a second capacitor 2232 , a first diode 2233 , and a second diode 2234 . The second capacitor 2232 is connected between an anode of the first diode 2233 and ground. A cathode of the first diode 2233 is connected to the output terminal 221 . A cathode of the second diode 2234 is connected to the anode of the first diode 2233 , and an anode of the second diode 2234 is connected to ground. The first capacitor 2231 of the first small voltage conversion circuit 223 is connected between the anode of the first diode 2233 of the first small voltage conversion circuit 223 and the first input terminal 211 . The first capacitor 2231 of the second small voltage conversion circuit 224 is connected between the anode of the first diode 2233 of the second small voltage conversion circuit 224 and the second input terminal 212 . The first capacitor 2231 of the third small voltage conversion circuit 225 is connected between the anode of the first diode 2233 of the third small voltage conversion circuit 225 and the third output terminal 262 of the main power supply 26 . In another embodiment, the first capacitor 2231 of the third small voltage conversion circuit 225 can be replaced by a resistor or an inductor.
When the main power supply 26 operates, the large voltage conversion circuit 222 and the small voltage conversion circuit 223 , 224 , 225 all supply the energy storage capacitor 250 of the energy storage circuit 25 . When the main power supply 26 is in a stand-by state, only the small voltage conversion circuit 223 , 224 , 225 supply the energy storage capacitor 250 .
FIG. 4 is a circuit diagram of one embodiment of the stand-by pilot circuit 24 of FIG. 1 . In one embodiment, the stand-by pilot circuit 24 includes a capacitor 241 , a first transistor 242 , a second transistor 243 , a light emitting diode 244 , a third diode 403 , a fourth diode 404 , and a zener diode 245 . The first transistor 242 is a positive-negative-positive (PNP) bipolar transistor, and the second transistor 243 is a negative-positive-negative (NPN) bipolar transistor. However, it may be understood that first transistor 242 and the second transistor 243 may be replaced by a P-channel metal oxide semiconductor (PMOS) transistor and a N-channel metal oxide semiconductor (NMOS) depending on the embodiment.
An emitter (not labeled) of the first transistor 242 is connected to a cathode of the third diode 403 via a resistor (not labeled), and an anode of the third diode 403 is connected to the output terminal 221 of the voltage conversion circuit 22 . The emitter of the first transistor 242 is also connected to ground via the capacitor 241 . A collector (not labeled) of the first transistor 242 is connected to an anode of the light emitting diode 244 , and a cathode of the light emitting diode 244 is connected to ground. A base (not labeled) of the first transistor 242 is connected to a cathode of the fourth diode 404 , and an anode of the fourth diode 404 is connected to the first output terminal 260 of the main power supply 26 . The base of the first transistor 242 is also connected to the emitter of the first transistor 242 via a resistor (not labeled). A collector (not labeled) of the second transistor 243 is connected to the base of the first transistor 242 via a resistor (not labeled). An emitter (not labeled) of the second transistor 243 is connected to ground. A base (not labeled) of the second transistor 243 is connected to an anode of the zener diode 245 . A cathode of the second transistor 243 is connected to the emitter of the first transistor 242 .
When the main power supply 26 operates, the voltage, for example, 26V, outputted from the first output terminal 260 is loaded on the base of the first transistor 242 . The first transistor 242 is turned off, and the light emitting diode 244 is turned off.
When the main power supply 26 is in the stand-by state, the voltage outputted from the first output terminal 260 is about zero. The voltage conversion circuit 22 charges the capacitor 241 via the output terminal 221 . When voltage of the capacitor 241 reaches a certain value, the zener diode 245 is turned on. The second transistor 243 is turned on correspondingly. The base of the first transistor 242 is pulled down to a low level via the actived second transistor 243 . The first transistor 242 is turned on correspondingly. The capacitor 241 discharges via the first transistor 242 and the light emitting diode 244 , and the light emitting diode 244 emits light.
When the voltage of the capacitor 241 discharges to a certain value, the zener diode 245 is turned off. The first transistor 242 and the second transistor 243 are turned off, the light emitting diode 244 stops emitting lights, correspondingly. The small voltage conversion circuit 223 , 224 , 225 charge the capacitor 241 again. When the voltage of the capacitor 241 reaches the certain value, the light emitting diode 244 emits light again. That is, the capacitor 241 is charged and discharged continuously when the main power supply 26 is in the stand-by state and the light emitting diode 244 flicks continuously. This indicates that the power supply circuit 20 is in the stand-by state.
FIG. 5 is a circuit diagram of one embodiment of the stand-by control circuit 27 of FIG. 1 . The stand-by control circuit 27 includes a switch 273 , a trigger 274 , a transistor 275 , an optical coupler 276 , a fifth diode 405 , a sixth diode 406 , a seventh diode 407 , an eighth diode 408 , and a reverser 277 . The switch 273 is used for manually controlling the power supply circuit 20 by the user. The switch 273 can be a touch switch, a unidirectional switch, or a bidirectional switch depending on the embodiment. The transistor 275 can be an NPN bipolar transistor or a metal-oxide-semiconductor field-effect transistor.
The switch 273 includes two terminals. One of the terminals of the switch 273 is connected to the trigger 274 , and the terminal is also connected to a cathode of the fifth diode 405 . The other terminal is connected to ground. An anode of the fifth diode 405 is connected to the second output terminal 272 of the stand-by control circuit 27 . A base of the transistor 275 is connected to the trigger 274 . An emitter of the transistor 275 is connected to an anode of a light emitting diode of the optical coupler 276 . A collector of the transistor 275 is connected to the trigger 274 . The collector of the transistor 275 is also connected to a cathode of the sixth diode 406 , and an anode of the sixth diode 406 is connected to the output terminal 251 of the energy storage circuit 25 . The output terminal 271 of the stand-by control circuit 27 is connected to a collector of a phototransistor of the optical coupler 276 via the reverser 277 . A cathode of a light emitting diode of the optical coupler 276 is connected to ground, and an emitter of a phototransistor of the optical coupler 276 is connected to ground. The first output terminal 281 of the microprocessor 28 is connected to an anode of the seventh diode 407 , and a cathode of the seventh diode 407 is connected to the trigger 274 . The second output terminal 282 of the microprocessor 28 is connected to an anode of the eighth diode 408 , and a cathode of the eighth diode 408 is connected to the base of the transistor 275 . The trigger 274 is also connected to the second output terminal 293 of the stand-by detecting circuit 29 .
When the power supply circuit 20 is in the stand-by state, the main power supply is shut down. Therefore, energy consumption of the power supply circuit 20 decreases compared to conventional art.
FIG. 6 is a schematic view of a power supply circuit 30 according to a second embodiment of the present disclosure. The power supply circuit 30 is similar to the power supply circuit 20 . However, the power supply circuit 30 further includes a relay 313 . The second input terminal 212 is connected to the commutating and filter circuit 33 via the relay 313 . When the power supply circuit 30 is in the stand-by state, the stand-by control circuit 37 outputs a control signal to turn off the relay 313 . The power supply circuit 30 is turned off correspondingly.
It is to be further understood that even though numerous characteristics and advantages of the present embodiments have been set out in the foregoing description, together with details of the structures and functions of the embodiments, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed. | An exemplary power supply circuit configured for supply power for a load includes: a main power supply configured for converting received voltages into required direct current voltages; a microprocessor configured for providing control signals; a stand-by control circuit configured for controlling the main power supply; an energy storage circuit configured for supplying the stand-by control circuit. When the load stops operating, the microprocessor outputs a control signal to the stand-by control circuit, the stand-by control circuit outputs a corresponding control signal to turn off the main power supply. In response to when the load starts operating, the stand-by control circuit outputs a corresponding control signal to turn on the main power supply, and the main power supply charges the energy storage circuit. | 7 |
BACKGROUND OF THE INVENTION
The invention relates to filtration systems and, in particular, to a self-supporting filter that is readily fixed to or positioned on or in equipment intakes.
Clean air is important in the efficient operation of a variety of machines and systems. Forced-air cooling and heating systems, internal combustion engines, and even office equipment require clean air for proper operation. In most instances, filters are specially designed to fit into or onto an intake of the device with which the filter is used. This requires manufactures to produce a large variety of differently shaped and configured filters. For example, some filters come in numerous sizes based on width, length, and height. Of course, the near endless number of different filter sizes and configurations makes replacing filters difficult for users. In order to replace a used filter, an exact replacement filter of the correct size and style must be purchased. This is true even though the filtering media used in differently sized filters is often the same or very similar. When the exact filter needed is not available or out-of-stock, special ordering arrangements must be made.
SUMMARY OF THE INVENTION
Although current filters are functional, the system of making custom filters for each application is inefficient. The invention provides a filter that can be cut-to-fit or deformed to fit a variety of differently shaped and sized intakes. The invention also provides a filter kit that allows a user to create a filter of a desired size with attaching mechanisms to secure the filter to or on the intake.
The present invention is directed to a filter assembly that includes a self-supporting filter media and a plurality of attachment strips. The self-supporting filter media is configured to filter non-gaseous items from a gas flow. The attachment strips have a first portion that is attachable to the filter media and a second portion that is attachable to a housing surrounding an intake.
The present invention is also directed to a filter assembly that includes a filter media, a deformable frame, and attachment strips. The deformable frame is positioned around at least a portion of the filter media. The attachment strips have first sides and second sides. The first sides are attached to the deformable frame and the second sides are removably attachable to a housing surrounding an inlet.
The present invention is also directed to a method of mounting a filter to an intake on a housing. The method includes selecting a filter media, forming the filter media to a desired size to match the size and contours of the intake, fitting attachment strips along the periphery of the filter media, and securing the filter media to the intake with the attachment strips.
Other features and advantages of the present invention will become apparent by consideration of the detailed description and accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view illustrating an apparatus with an air intake and a filter assembly of one embodiment of the present invention.
FIG. 2 is an enlarged perspective view of the filter assembly shown in FIG. 1 .
FIG. 3 is an exploded view of the filter assembly shown in FIG. 1 .
FIG. 4 is a partially-sectioned front view of the filter assembly shown in FIG. 1 .
FIG. 5 is a cross-sectional view taken along line 5 — 5 in FIG. 4 .
FIG. 6 is a perspective view illustrating an apparatus with an intake and a filter assembly of an alternative embodiment of the present invention.
FIG. 7 is a partially-sectioned front view of the filter assembly shown in FIG. 6 .
FIG. 8 is a cross-sectional view taken along line 8 — 8 in FIG. 7 .
DETAILED DESCRIPTION
Before embodiments of the invention are explained, it is to be understood that the invention is not limited in its application to the details of the construction and the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced or being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting.
FIG. 1 illustrates an apparatus 10 such as an air conditioner or heat pump which includes a housing 12 with an air intake 14 (FIG. 2) and an air outlet (not shown). A fan (not shown) operates to draw air (creating an air or gas flow) through the air intake 14 into the housing 12 and through the air outlet. A filter assembly 16 is connected to the housing 12 and covers the intake 14 to prevent debris, contaminants, and other non-gaseous items present within the air from entering into the housing 12 through the intake 14 .
As shown in FIG. 3, the filter assembly 16 includes a filter 18 and attachment strips 20 . The filter 18 is detachably connected to the housing 12 around the intake 14 by the attachment strips 20 , such as VELCRO hoop and loop fastening strips. FIGS. 4 and 5 further illustrate that the attachment strips 20 are generally located around the perimeter of the filter 18 . The attachment strips 20 can be separate strips that are cut to length by scissors or the like and combined to cover the perimeter of the filter 18 . Alternatively, the attachment strips 20 could be made of a single integral piece that is cut to size by a cutting die.
The attachment strips 20 includes a first portion 22 that is attached to the housing 12 and a second portion 24 that is attached to the filter 18 . The first portion 22 includes an adhesive face 26 that is attachable to the housing 12 and a hook and loop face 28 . The second portion 24 includes an adhesive face 30 that is attachable to the filter 18 and a hook and loop face 32 that is removably attachable to the mating hook and loop face 28 on the first portion 22 of the attachment strip 20 . Alternatively, the second portion 24 of the attachment strip 20 could be attached to the filter 18 by stitching, stapling, gluing, taping, or the like. It should be noted that only a single portion of an attachment strip 20 could be used to attach the filter to the housing. Specifically, an adhesive face 26 of the single portion attaches to the housing 12 , and a hook and loop face 32 of the single portion fastens directly to the filter 18 .
As best shown in FIG. 5, the filter 18 is a washable, semi-rigid, three-dimensional type, synthetic media filter. In the illustrated embodiment, the three-dimensional type filter is a corrugated weave filter as opposed to a flat woven screen or other two-dimensional type filter. Three-dimensional type filters generally include a thickness component that increases the effectiveness of the filter and provides the filter with increased stability compared to the two-dimensional type filters. In contrast to typical filters that are mounted inside of equipment, the illustrated filter 18 is mounted to the exterior of equipment, and, therefore, the synthetic media is UV protected and is protected from degradation due to exposure to sunlight and hostile environments (e.g. rain, chemicals, oil, etc.). The filter 18 has a permanent electrostatic charge to facilitate the pickup of dust and other airborne contaminants. The filter 18 is self-supporting and is therefore capable of maintaining its shape under the pressure of its own weight. The filter 18 is, however, easily deformable to match the contours of the surface of the housing 12 .
In the illustrated embodiment, the filter 18 includes a corrugated layer 34 and a base layer 36 , each made of woven synthetic polymer fibers. The corrugated layer 34 is woven together with the base layer 36 and a top layer 38 such that the corrugated layer 34 is between the base layer 36 and the top layer 38 . The top layer 38 includes a plurality of threads that extend transversely to the corrugation direction of the corrugated layer 34 .
It can be seen that a custom-sized filter assembly 16 can be easily constructed by an individual on site with minimal materials. A filter kit, including bulk rolls or amounts of filter material and attachment strips, is all that would be necessary for an individual to create a filter assembly 16 to fit over almost any sized intake 14 opening. For example, the filter material could easily be cut by a pair of scissors to form a filter 18 that would cover an intake 14 opening. Next, attachment strips could be cut to length from the bulk roll so that the attachment strips 20 would substantially outline the perimeter of the filter 18 . After adhering the adhesive side 26 of the first portion 22 around the intake 14 of the housing 12 and the adhesive side 30 of the second portion 24 around the filter 18 , the hook and loop sides 28 , 32 of the first and second portions 22 , 24 could be removably attached to each other such that the filter 18 covers the intake 14 opening in the housing 12 .
FIG. 6 illustrates an apparatus 10 that includes an intake 14 and a filter assembly 40 of an alternative embodiment of the present invention. The apparatus 10 includes a housing 12 with the air intake 14 and an air outlet (not shown). A fan (not shown) operates to draw air in through the air intake 14 into the housing 12 and through the air outlet. The filter assembly 40 is connected to the housing 12 and covers the intake 14 to prevent debris and contaminants in the air from entering into the housing 12 through the intake 14 .
As shown in FIGS. 7 and 8, the filter assembly 40 includes a filter 42 , a support structure 44 , a frame 46 , and attachment strips 48 . The filter 42 and the support structure 44 are supported within the frame 46 such that the filter 42 and the support structure 44 are adjacent to each other. The filter 42 can be any known filter media and is prevented from substantial movement in one direction by the support structure 44 . The support structure 44 is a thin metal screen that is an expanded metal media designed to support the filter 42 and allow air flow through the filter. The support structure 44 is typically manufactured by cutting offset slits into a sheet of the metal material and pulling the metal sheet in a direction that is perpendicular to the direction of the slits.
The frame 46 includes multiple C-shaped and thin-walled metal channels 50 that are assembled to enclose and support the support structure 44 and the filter 42 . The metal frame 46 and support structure 44 are substantially rigid, however they are also semi-flexible such that the frame 46 and support structure 44 can be formed to match the contours of the housing 12 to which it is attached. In addition, the frame 46 allows slight flexing to effectively seal against a flat surface that is not perfectly planar. Alternatively, the support structure 44 and the frame 46 could be made from an easily flexible polymer material such as polypropylene, polyester, polyethylene, or the like.
The frame 46 is attached to the housing 12 by the attachment strips 48 , such as magnetic strips. The attachment strips 48 include adhesive sides 52 which are attached to the frame 46 and magnetic sides 54 that are detachably attached to the metal housing 12 around the intake 14 opening. Alternatively, the attachment strips 48 could be glued to the frame 46 or the frame 46 itself could be magnetized to facilitate the connection with the housing 12 .
As can be seen from the above, the invention provides, among other things, a filter assembly 40 and/or filter kit that can be (i) cut to fit a variety of intake 14 openings; (ii) simply placed over the intake 14 opening with the attachment strips 20 , 48 to conveniently and reliably filter air flowing into the housing 12 through the 30 intake 14 ; and (iii) formed to match irregularities that are present in the housing 12 of different apparatuses 10 to which the filter assembly 16 , 40 can be attached. Various features and advantages of the invention are set forth in the following claims. | The invention provides a filter that can be cut-to-fit or deformed to fit a variety of differently shaped and sized intakes. The invention also provides a filter kit that allows a user to create a filter of a desired size with attaching mechanisms to secure the filter to or on the intake. | 8 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to aqueous slurries. In particular, the invention concerns improved methods of dispersing solids and latexes in aqueous media. The invention also relates to methods of immobilizing latexes on the surface of solid particles.
[0003] 2. Description of Related Art
[0004] Aqueous latex dispersions have a wide range of applications in industry. They are employed for producing coating and surface treatment compositions for use, e.g., in the paper and pulp industry and in the paint industry. In these applications, some light scattering pigments are typically incorporated into the dispersion to form a coating colour or paint composition. Examples of suitable inorganic pigments include precipitated and ground calcium carbonate for coating colours and titanium dioxide for paint compositions.
[0005] Conventionally, the inorganic particles are dispersed into the latex dispersion with the aid of a dispersing agent under vigorous stirring. A pigment-latex dispersion is then obtained wherein most of the latex polymer is present in the free state, i.e. not bonded to the inorganic particles.
[0006] A novel kind of aqueous pigment-latex slurries are disclosed in our earlier patent application no. 07397007.1, titled Aqueous Dispersions and Method for the Production Thereof, filed on 30 Mar. 2007, the contents of which are herewith incorporated by reference. In these pigment-latex slurries, at least a part of the dispersing agent is adsorbed onto the latex particles in a first step of the process to provide modified latex particles, and the adsorbed dispersing agent will assist in immobilizing the modified latex particles on the surfaces of the solids.
[0007] In the earlier application, contacting of the modified latex with the solid particles is carried out with intensive mixing.
SUMMARY OF THE INVENTION
[0008] It is an aim of the present invention to provide an alternative method of producing a stable aqueous dispersion of a latex, solid particles and a dispersing agent.
[0009] It is another aim of the invention to provide a method of immobilizing latex on the surface of solid particles.
[0010] As known in the art, solid particles are often provided in the form of a granular powder containing agglomerated fine particles. Typically this is the case for precipitated calcium carbonate and similar precipitated particles, which are supplied and used in the form of moist filter cakes. For the preparation of, e.g., coating colours, these filter cakes need to be slurried and the agglomerates should be broken up (desagglomerated) before the particles are dispersed with the aid of conventional dispersing agents.
[0011] As mentioned above, in the novel technology the modified latexes are contacted with the pigments under intensive mixing. In the context of the present invention we have found out that both the step of desagglomeration of the inorganic solids and the step of contacting the particles with the modified latex are preferably carried out in a zone of high shear forces. Preferably, the latex polymers should be present during desagglomeration so as to be able immediately to occupy the free sites of the surfaces of the solid particles—in other words, the two processes should be carried out as close to each other as possible, preferably simultaneously.
[0012] Conventional mixing processes are not sufficient to meet these demands. According to our trials, conventional mixing blade does not provide a sufficiently high shear field to allow for dispersing within industrially reasonable processing times. Furthermore, conventional mixers only randomly break the agglomerates, which further extend the dispersing time.
[0013] The invention is therefore based on the finding that pigment and other solid particles can be efficiently dispersed with a modified latex, obtained by contacting a conventional latex with an anionic dispersing agent, if they are subjected to high shear forces by conducted them—either mixed together or separately fed-through a zone of high shear forces to form a latex-particle slurry. Since the raw-materials are fed through the zone of high shear forces, said forces are exerted to all or practically all of the raw-materials. By contrast, with conventional mixers, the high shear zone only comprises a minor part of the raw-materials.
[0014] More specifically, the method of producing an aqueous dispersion according to the present invention is characterized by what is stated in the characterizing part of claim 1 .
[0015] The method of immobilizing latex on solid particles is characterized by what is stated in the characterizing part of claim 30 .
[0016] Considerable advantages are obtained by the invention. Thus, in the present method the lead-time is shortened and there is no need to compromise in the technology by using too much dispersing agent. Surprisingly it was noticed that the present invention allows for much better attachment of the used polymer to the solids, such as precipitated calcium carbonate (PCC) and the new process provided is capable of handling the high viscosity of the product. The present method is economical on industrial scale, and it appears that the dosage of the dispersing agent can even be slightly reduced, as can energy consumption of dispersing.
[0017] Our results show that high adsorption rates can be reached of over 60 wt-% of the latex adsorbed on the solids. The high adsorption value (latex immobilization) appears to increase the surface strength of final coating layer and therefore allows for a decrease of latex consumption. The efficiency of the high shear mixer makes it possible to reduce the polymer dosages needed for achieving reasonable good rheology properties of product. This is probably due to the ability of the high shear mixer to open the surfaces of undispersed pigments before the addition of incremental dispersing agent.
[0018] With the particularly preferred rotor-rotor-mixer described below, extremely high and focused shear can be produced, and with such a mixer the high viscosity of the slurry can be dealt with.
[0019] Compared to conventional mixers, the energy consumption, calculated per weight (dry weight) of the slurry treated or produced, is much smaller. As the examples below show, it is possible to cut energy consumption (kWh/t) with at least 20%, preferably at least 40%, compared to conventional mixing technology.
[0020] The novel dispersions can be used as coating colours for coating of paper or cardboard, or in paint applications.
[0021] Next the invention will be examined more closely with the aid of a detailed description and with reference to a number of working examples and to the attached drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] FIG. 1 shows the process scheme for a preferred embodiment of the invention, comprising a cascade of two high-shear forces mixers and indicating the feed points of the polymers used in the invention;
[0023] FIG. 2 shows the process scheme for a first one-mixer embodiment of the invention used in Example 1;
[0024] FIG. 3 shows the process scheme for a second one-mixer embodiment of the invention used in Example 2;
[0025] FIG. 4 shows the process scheme for a first mixer cascade embodiment of the invention used in Example 3;
[0026] FIG. 5 shows the process scheme for an embodiment outside the invention, wherein a conventional mixer is used (cf. Example 4); and
[0027] FIG. 6 shows the process scheme for a second mixer cascade embodiment of the invention (Example 5).
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0028] In order to immobilize latex on the surface of solid particles, a modified latex of the aforementioned kind is first admixed with the solid particles in the presence of water to form an aqueous mixture, and the modified latex are then intimately mixed with the solids particles to adsorb at least a part of the modified latex onto the particles by conducting the mixture through said zone of high shear forces.
[0029] The process therefore comprises the steps of
contacting the latex with an anionic dispersing agent to form a modified latex, feeding the modified latex and the solid particles to a zone of high shear forces, and simultaneously subjecting essentially all of the modified latex and the solid particles fed to said zone to high shear forces therein to form a latex-particle slurry.
[0033] It is preferred to mix the modified latex with intact pigment in order to reach high adsorption rate. In particular, no incremental dispersing agent is added prior or at the same time with latex, because such addition may lower the latex adsorption rate achieved.
[0034] Preferably, the modified latex is first admixed with the solid particles in the presence of water to form an aqueous mixture and the aqueous mixture is conducted through the zone of high shear forces. It is also possible to separately feed the modified latex and the solid particles into the zone of high shear forces.
[0035] Typically in a mixer with high shear forces, the hold-up of the material passing through the mixing zone is short. Accordingly, the residence time (pass time) of the modified latex and the solid particles fed in the zone of high shear forces is about 0.01 to 60 seconds, in particular about 0.1 to 30 seconds. The feed rate of the pigment is typically about 100 to 10,000 g/s, in particular about 200 to 5,000 g/s. The feed rate of the modified latex is on the same order of magnitude as for the pigment.
[0036] Essentially all, preferably at least about 90 wt-%, in particular at least 95 wt-%, advantageously at least 99 wt-%, of the modified latex and the inorganic pigment are passed through the zone of high shear forces.
[0037] In the zone of high shear forces, the modified latex and the solid particles are subjected to high shear forces. Typically, the energy intensity is in excess of 500 kWh/m 3 , in particular 800 kWh/m 3 or greater, suitably in excess of 1,000 kWh/m 3 , preferably it is about 1,100 kWh/m 3 to 10,000, and advantageously the energy intensity is approximately 1,100 to 6,000 kWh/m 3 . The energy intensity is calculated based on the volume occupied by the materials fed into the high shear zone.
[0038] In the examples, two different kinds of mixers were used, viz. an impact mixer (Atrex CD350, supplied by Megatrex Oy, Lempäälä, Finland) which comprises two counter rotating mixing elements (rotors), which produce high shear forces and wherein all of the feed, due to the geometry of the mixer, is forced through the zone of high shear forces formed by the rotors. The Atrex CD350 is supplied with two different motors (18.5 and 22 kW), it has a circumference diameter was 0.35 m and the motors were operated with 40 Hz frequency denoting 21.5 m/s radial velocity for the outermost rim. Under the operating conditions of the below examples, the Atrex CD350 typically generates an energy intensity of about 800 to 1550 kWh/m 3 .
[0039] The conventional mixer employed was a blade mixer of the type Diaf FFB H3 dissolver—with a 1.85 kW motor and operated at a radial velocity of 36 m/s (supplied by DIAF AS, Slagelse, Denmark). Although the blade mixer produces high shear forces at the rim of the blade, there is not formed a zone of high shear forces, through which all or practically all of the material would be forced. Or in other words, with a conventional mixer, it is not possible to subject simultaneously essentially all the material to high shear forces. The pin mills may comprise, e.g. single and/or double rotor mixers. Thus, the apparatus comprises vane rings rotating in different directions, or a rotating vane ring and a non-rotating vane ring.
[0040] The impact mixer typically has a drum of fairly low height and a feed orifice (inlet) is provided in the upper part thereof. One or more vane rings, or grinding rotors, are arranged inside the drum such that at least one of the rotors is rotatably mounted on bearings. The second rotor is statically mounted or rotatable. Thus, a first embodiment comprises a double-ring impact mixer mill wherein both mixing rotors are rotatable, and a second embodiment comprises a mixer where stators with perpendicular mixing pins are provided between the rotatable pin rotors. The planar circumferential disks of the mixing rotors rings are equipped with perpendicular pins.
[0041] There are also other mixers capable of providing the required zone of high shear forces through which all of the solids and latex can be conducted. One suitable mixer kind is the Cavitron Rotor/Stator Mixer supplied by v. Hagen & Funke GmbH, Sprockhövel, Germany.
[0042] In an alternative embodiment, before the raw-materials are fed into the first zone of high shear forces, a pre-dispersing step can be carried out. The pre-dispersing can be performed in a conventional mixer, e.g. a blade mixer, which is connected to the first of the high shear mixers. During the pre-dispersing step, undispersed pigment surface is partly opened, which enables latex adsorption on it. Should the resulting dispersion be too viscous, conventional dispersing agent can be added to restore flowability of slurry for the sake of pumpability. The slurry is then conducted to the first high shear mixer, where the rest of surface area is exposed to adsorption. The dispersing agent used in the pre-dispersing step may reduce the adsorption of modified latex onto the solid pigments during the following contacting/adsorption steps.
[0043] The mixing comprises at least one high shear mixer having at least one rotating rotor element. The mixer may comprise at least one high shear mixer having at least one static stator element and at least one rotating rotor element.
[0044] According to a preferred embodiment, at least one of the high shear mixers is of a kind having at least two counter-rotating rotor elements. Such a high shear mixer has at least two counter-rotating rotor elements displaced at a distance of 1 to 10 mm and equipped with several concentric rows of grinding elements, said rotor elements being capable of rotating at a speed of approximately 500 to 5000 rpm. In the examples disclosed below, a high shear force mixer of the type Atrex with two counter-rotating rotors is used.
[0045] The contacting/mixing/adsorption step can be carried out in one zone of high shear forces.
[0046] In order to increase adsorption, it is however preferred to feed the modified latex and the solid particles into a cascade of mixing zones comprising at least two high shear mixers in a series. Generally the cascade comprises 2 to 4 high shear mixers.
[0047] In a cascade of the above kind, at least two of the mixing zones are arranged in such a way that all of the effluent of one mixing zone is fed by gravity into a succeeding mixing zone.
[0048] The high shear mixers can in practice be located one upon the other. According to one preferred embodiment, the wet undispersed filter cake is fed into the upper mixer, wherein it is combined with the latex under high shear forces. The resulting dispersion is usually thick, paste-like. By arranging the next high shear mixer below the preceding, the dispersion will fall down to the lower mixer by gravity and there is no need for improving flowability of the dispersion. In the second mixer, further opening of pigment surface takes place in the presence of latex.
[0049] At least two of the mixing zones can also be arranged in such a way that the effluent of one mixing zone is conducted with a conveyor screw into a succeeding mixing zone.
[0050] FIG. 1 shows an embodiment of the present invention, wherein two mixing zones 1 and 2 are arranged in a cascade. The first mixer 1 is provided with feed nozzles for the pigment, water and the modified latex (Polymer A). The effluent of the first mixer 1 can be conducted to a second mixer 2 arranged in serial configuration with the first to allow for increased dispersion. It is possible to diverge a side stream of the effluent, which can be separately treated, but preferably all of the effluent from the first mixer 1 is conducted directly to the second mixer 2 .
[0051] The mixed slurry is then withdrawn from the second mixer 2 and it can be fed into a conventional mixing tank 3 , which comprises for example a blade mixer. A second dispersing agent (Polymer B) can be added, as will be discussed below, and the temperature of this mixing step is controlled 4 , for example with internal or external water-cooling of the tank, and if desired samples can be taken from sample valve 5 . After a preset mixing period, or after the preset viscosity has been reached, a pigment/latex slurry is withdrawn from mixer 3 .
[0052] It should be pointed out that the conventional mixer 3 is optional but preferred, because it facilitates the adjustment of the viscosity and flowability. In particular, when an additional dispersing agent is added to the latex-solids slurry as shown in FIG. 1 it allows for adjustment of the flowability of the slurry. This additional dispersing agent is preferably added to the slurry using a conventional mixer, e.g. of the kind mentioned above, although it is naturally possible to add it to the slurry in connection with high shear forces mixing. The additional dispersing agent is dosed purely from the rheology point of view (it is not needed to aid opening of the solids surfaces or pumpability during process) and therefore the competing adsorption with latex do not appear during process.
[0053] Generally, it is preferred to use a dispersing agent that has a lower charge density than the dispersing agent used for modification of the latex. Such a dispersing agent is less competitive with the modified latex for binding to the pigment or solids surface.
[0054] The preparation of the modified latex is described in our co-pending patent application no. 07397007.1, titled Aqueous Dispersions and Method for the Production Thereof, filed on 30 Mar. 2007, the contents of which are herewith incorporated by reference.
[0055] A typical composition of the dispersion comprises about 1 to 25 parts by weight, preferably about 2 to 20 parts by weight, of latex and dispersing agent per 100 parts by weight of the inorganic particles.
[0056] The amount of dispersing agent varies, but it is generally about 0.01 to 10 parts per hundred (pph), preferably between 0.2 and 8 pph, in particular 1 and 7 pph parts per 100 parts of dry pigment.
[0057] Latex dosage lies between 2 and 9 parts per hundred (pph), preferably between 4 and 7 pph, in particular 5 and 6 pph. The dosage refers to 100 parts of pigment.
[0058] These compositions will provide for a significant reduction of the latex consumption compared to conventional dispersions.
[0059] For the purpose of the present invention, the term “latex” stands for a water emulsion of small colloidal polymeric particles having an average particle size of about 10 to 1000 nm. The “latex polymer” stands for the polymer of these colloidal particles and “polymer latex dispersion” stands for an aqueous dispersion of latex polymer, dispersant and inorganic particles.
[0060] The latex polymer used in the invention can, basically, be of any conventional kind. Thus, soft latex polymers, such as styrene-butadiene (SB), styrene-butyl acrylate (SBA) and polyvinyl acetate (PVAc) can be used. According to the invention, for example a latex polymer of any of the above types, or mixtures thereof, is used as a base latex to which the dispersion agent is bonded. The latex comprises typically (polymer) particles having an average particle size of about 80 to 150 nm, preferably about 110 to 120 nm.
[0061] The anionic dispersing agent used for the modification of the latex is typically of a kind that has a charge density of at least 14.1 meq/g, based on a polymeric structure in fully dissociated state, formed by acrylic acid monomers optionally copolymerized or grafted with monomers having several acid groups.
[0062] The modified latex is produced by contacting a first dispersing agent with the latex to form a modified latex, and a second portion of the dispersing agent is mixed with the aqueous slurry after the addition of the modified latex.
[0063] The dispersing agent is a polymeric compound having acid groups derived from acrylic acid and maleic acid. As a specific example, the dispersing agent can be sodium polyacrylate based. The dispersing agent has a charge density of at least 14.5 meq/g, preferably at least 15.8 meq/g.
[0064] As discussed above, the present dispersing method allows for the use of additional dispersing agent (Polymer B in FIG. 1 ), which is added separately, not bound to the latex. According to a particularly preferred embodiment, the separately added dispersing agent is different from the one use for modifying the latex. Thus, it is possible to proceed in such a way that a first portion of a first dispersing agent is contacted with the latex to form a modified latex, and a second portion of a second dispersing agent, different from the first one, is mixed with the aqueous slurry after the addition of the modified latex. The first portion of the dispersing agent comprises about 10 to 95 wt-%, preferably about 20 to 90 wt-%, in particular about 40 to 90 wt-%, of the total amount of the dispersing agent.
[0065] The second dispersing agent can also be selected from the group of polyphosphates, lignin sulphonic acid salts, carboxylic acid salts and amine compounds.
[0066] The molecular weights (M w ) of the above polymeric dispersing agents are generally about 1,000 to 150,000 g/mol, typically about 10,000 to 100,000 g/mol, for example about 15,000 to 80,000 g/mol and in particular 20,000 to 70,000 g/mol. The degree of polymerisation is about 50 to 750, preferably about 100 to 250.
[0067] The method is carried out at a temperature of less than 85° C. during the preparation of the dispersion. Preferably, the method is operated at ambient temperature. The pH of the dispersion is maintained in the range of 6.5 to 10, preferably about 7.5 to 9.5.
[0068] The solid particles comprise mineral or organic pigments, particles, fibres or granules. It is particularly interesting to produce the slurries from mineral pigments, which comprise precipitated particles. Such mineral pigments can be selected from the group of precipitated calcium carbonate, ground calcium carbonate, kaolin, titanium dioxide, gypsum, talc and barium sulphate, and mixtures thereof.
[0069] The pigments, particles and granules employed can be of a conventional coating-grade quality. It is also possible to employ the invention to pigments, particles and granules of filler-grade qualities. Thus, the average particle size of the solid particles can vary broadly in a range of about 0.01 to 1000 um, in particular about 0.05 to 100 um, preferably about 0.1 to 50 um. The shape of the particles is not limited to any particular form (spherical, oblong, platey, rhombical, etc.), as indicated by the various materials mentioned above.
[0070] Light-scattering pigment grades as well as opacity-enhancing filler grades are particularly interesting.
[0071] The latex-solids slurry, which is an aqueous slurry, has a solids content of at least 10%, preferably at least 20%, advantageously 50%, and in particular 60 to 95% by weight of the slurry. For coating colours, the solids content is in particular about 50 to 80% by weight and for paint compositions it is 20 to 60% by weight. For filler compositions the solids content can be e.g. about 10 to 60% by weight.
[0072] In order to increase the solids content, water may be removed for instance by evaporation, for example in a vacuum evaporator.
[0073] Basically, the dispersions can be used as such. However, the properties of the dispersions can be adjusted by incorporating various conventional additives and auxiliary agents. Such agents are, in addition to the dispersants discussed above, agents affecting the viscosity and water retention of the mix (e.g. CMC, hydroxyethyl cellulose, polyacrylates, HASEs, alginates, benzoate), so-called lubricants, hardeners used for improving water-resistance, optical auxiliary agents, anti-foaming agents, pH control agents, and preservatives.
[0074] The following examples illustrate the invention.
Example 1
[0075] This example illustrates dispersing of an inorganic pigment using a latex grafted with dispersing agent K5, an anionic acrylic acid based dispersing agent which contains 62 mole-% acrylic acid and 38 mole-% maleic acid (corresponding to a weight ratio of 50:50 of the acrylic versus maleic acid monomers). K5, supplied by Kemira Oyj, Finland, has a charge density of about 15.8 meq/g and a weight average molecular weight (M w ) of 15,600.
[0076] The process configuration is shown in FIG. 2 .
[0077] The components are first premixed with a Diaf mixer 11 and then the slurry is conducted once through an Atrex impact mixer 13 . The water cooling temperature control of the Diaf mixer 12 was installed in order to maintain temperature below 85° C. However, the temperature did not exceed 35° C. in the any of experiments 1 to 5 and thus control was not needed. Samples can be taken through valve 14 .
[0078] First, 7,366 g wet, undispersed PCC pigment (Opacarb A40, supplied by Special Minerals Inc, Äänekoski, Finland) was weighed. The pigment was supplied in the form of a wet filter cake having a solid content of 67.9%, and the weighed amount therefore equaled 5,000 g dry pigment. Then, 9 parts of a modified latex (Latex 2B) was weighed against the dry pigment. Latex 2B comprised an SB latex of type (Litex PX 9292, supplied by Eka Polymer Latex Oy, Oulu, Finland), which had been modified by grafting 5 parts of dispersing agent K5 onto the SB latex polymer. The grafting is disclosed in more detail in the above-mentioned, co-pending patent applications. The weighed amount of the modified latex was 1108 g wet Latex 2B, having a solids content of 40.6%.
[0079] All the modified latex Latex 2B blend was placed in a 10 L round bottom stainless steel container 11 . Addition of Opacarb A40 into the container was initiated progressively by mixing the Latex 2B with a Diaf FFB H3 dissolver equipped with a Type-3 blade, diameter 4″ from Blade Shop Inc. (at 36 m/s radial velocity). After an addition of about 80% of the wet undispersed filter cake (about 5,900 g), the slurry turned very thick (toothpaste like). Dispersing agent K5 was separately added in an amount of 0.3 parts (per 100 parts of dry pigment, which corresponds to 35.3 g wet dispersing agent with a solid content of 42.5%) to restore the flowability of the slurry.
[0080] The rest of the undispersed pigment, about 1,500 g of the wet filter cake, was then added into the container. The slurry remained flowable in spite of this addition. The pH of the slurry was 8.8 without adjustment. The total mixing time in this phase was 30 min and, the material was subjected to an energy intensity of about 140 kWh/m 3 .
[0081] The pigment-latex slurry was then dispersed using an Atrex CD350 impact mixer 13 supplied by Megatrex Oy, Lempäälä, Finland. The slurry was passing through the unit once, the operating rate was 1,200 rpm denoting 21.5 m/s radial velocity for the outermost rim and the temperature was a. 35° C. The feeding rate of slurry into Atrex unit was about 830 g/s and, thus the delivery cycle of all material was 9 s. The material was subjected to an energy intensity of about 890 kWh/m 3 .
[0082] The high shear viscosity of slurry was measured by an ACAV-A2 Automated Ultra High Shear Viscometer by using 0.6×50 mm capillary at 25° C. [supplier: ACA Systems Oy, Outilantie 3, 83750 Sotkuma, Finland]. The viscosity value at the shear rate value 135,000 was 420 mPas. The static water retention was evaluated for slurry by an AA-GWR Water Retention meter measuring 30 s with 0.30 bar at 25° C. [supplier: Kaltec Scientific, Inc., 22425 Heslip Drive, Novi, Mich. 48375, USA]. The value was 141 g/m 2 .
[0083] The slurry was centrifuged with a Sorvall Instruments RC5C centrifuge equipped with an SS-34 rotor for 40 min at 26,500 G and 25° C. The latex content of the liquid phase was analyzed with a Shimadzu TOC-V CPH Total Organic Carbon (TOC) analyzer—the samples were diluted at a ratio of 1 to 250 and 1 to 500, respectively. Analysis against the calibration curve of Latex 2B revealed that about 23% of the latex was adsorbed to the pigment.
[0084] The energy consumption of the first mixing stage was 78 kWh/t and for the second about 6 kWh/t.
Example 2
[0085] In this example, inorganic pigment was dispersed using a latex grafted with dispersing agent (denomination K5, cf. Example 1). The slurry was directed once through Atrex impact mixer and then post-mixed with a Diaf mixer.
[0086] The process configuration is shown in FIG. 3 .
[0087] First, 7,366 g wet, undispersed PCC pigment (Opacarb A40, supplied by Special Minerals Inc, Äänekoski, Finland) was weighed. The pigment was supplied in the form of a wet filter cake having a solid content of 67.9%, and the weighed amount therefore equaled 5,000 g dry pigment. Then, 9 parts of a modified latex (Latex 2B) was weighed against the dry pigment. Latex 2B comprised an SB latex of type (Litex PX 9292), which had been modified by grafting 5 parts of dispersing agent K5 onto the SB latex polymer (cf. Example 1). The weighed amount of the modified latex was 1108 g wet Latex 2B, having a solids content of 40.6%.
[0088] Opacarb A40 and Latex 2B were fed into the dispersing chamber of an Atrex CD350 impact mixer 21 by constant ratio. The slurry was passing through the unit once, the operating rate was 1,200 rpm denoting 21.5 m/s radial velocity for the outermost rim and the temperature was approx. 35° C. The feed rate of slurry into the Atrex unit was about 830 g/s and, thus the delivery cycle of all material was 9 s. The material was subjected to an energy intensity of about 1530 kWh/m 3 .
[0089] The slurry (toothpaste like) was carried by gravity into a 10 L round bottom stainless steel container 22 and mixed 10 minutes with a Diaf FFB H3 dissolver equipped with Type-3 blade, diameter 4″ from Blade Shop Inc. (at 36 m/s radial velocity). The energy intensity was 143 kWh/m 3 . Dispersing agent K5 was added in an amount of 0.3 parts (per 100 parts of dry pigment, which amounts to 35.3 g wet dispersing agent with a solid content of 42.5%) to induce the flowability of the slurry. The pH of the slurry was 8.8 without adjustment. The temperature of the slurry was monitored 23 and when samples were taken through valve 24 .
[0090] The high shear viscosity of the slurry was measured with an ACAV-A2 Automated Ultra High Shear Viscometer by using 0.6×50 mm capillary at 25° C. [supplied by ACA Systems Oy, Outilantie 3, 83750 Sotkuma, Finland]. The viscosity value at the shear rate value 135,000 s −1 was 324 mPas. The static water retention was evaluated for slurry with an AA-GWR Water Retention meter measuring 30 s with 0.30 bar at 25° C. [supplied by Kaltec Scientific, Inc., 22425 Heslip Drive, Novi, Mich. 48375, USA]. The value was 143 g/m 2 .
[0091] The slurry was centrifuged with a Sorvall Instruments RC5C centrifuge equipped with an SS-34 rotor for 40 min at 26,500 G and 25° C. The latex content of liquid phase was then analyzed with a Shimadzu TOC-V CPH Total Organic Carbon (TOC) analyzer—the samples were diluted at a ratio of 1 to 250 and 1 to 500, respectively. Analysis against the calibration curve of Latex 2B revealed that about 68% of the latex was adsorbed to the pigment.
[0092] The energy consumption of the high shear forces mixing stage was 10 kWh/t and for the second, conventional stage about 26 kWh/t.
Example 3
[0093] This example discloses dispersing of an inorganic pigment using a latex grafted with dispersing agent K5, whereby the pigment/latex slurry is directed twice through an Atrex impact mixer and then post-mixed with a Diaf mixer.
[0094] FIG. 4 shows the configuration of the equipment, reference numerals 31 and 32 representing high-shear forces mixers and 33 a mixing tank, with temperature control 34 and sample valve 35 .
[0095] First, 7,366 g wet, undispersed PCC pigment (Opacarb A40, supplied by Special Minerals Inc, Äänekoski, Finland) was weighed. The pigment was supplied in the form of a wet filter cake having a solid content of 67.9%, and the weighed amount therefore equaled 5,000 g dry pigment. Then, 9 parts of a modified latex (Latex 2B) was weighed against the dry pigment. Latex 2B comprised SB latex of type (Litex PX 9292), which had been modified by grafting 5 parts of dispersing agent K5 onto the SB latex polymer. The weighed amount of the modified latex was 1108 g wet Latex 2B, having a solids content of 40.6%.
[0096] Opacarb A40 and Latex 2B were fed into the dispersing chamber of an Atrex CD350 impact mixer 31 by constant ratio. The resultant thick paste was carried by gravity to the next identical Atrex unit 32 . In the both cases the operating rate was 1,200 rpm denoting 21.5 m/s radial velocity for the outermost rim and the temperature was about 35° C. Energy intensity was about 1535 kWh/m 3 .
[0097] The Atrex units were each fed at a rate of about 830 g/s and the pass times were in both Atrex units about 9 s.
[0098] Finally the slurry (toothpaste like) was carried by gravity into a 10 L round bottom stainless steel container 33 and mixed for 5 minutes with a Diaf FFB H3 dissolver equipped with Type-3 blade, diameter 4″ from Blade Shop Inc. (at 36 m/s radial velocity, and an energy intensity of 71 kWh/m 3 ). Dispersing agent K5 was added in an amount of 0.3 parts (per 100 parts of dry pigment, which amounts to 35.3 g wet dispersing agent with a solid content of 42.5%) to induce the flowability of the slurry. The pH of the slurry was 8.8 without adjustment.
[0099] The high shear viscosity of slurry was measured with an ACAV-A2 Automated Ultra High Shear Viscometer by using 0.6×50 mm capillary at 25° C. [supplied by ACA Systems Oy, Outilantie 3, 83750 Sotkuma, Finland]. The viscosity value at the shear rate value 135,000 s −1 was 287 mPas. The static water retention was evaluated for slurry with an AA-GWR Water Retention meter measuring 30 s with 0.30 bar at 25° C. [supplied by Kaltec Scientific, Inc., 22425 Heslip Drive, Novi, Mich. 48375, USA]. The value was 146 g/m 2 .
[0100] The slurry was centrifuged with a Sorvall Instruments RC5C centrifuge equipped with an SS-34 rotor for 40 min at 26,500 G and 25° C. The latex content of liquid phase was then analyzed with a Shimadzu TOC-V CPH Total Organic Carbon (TOC) analyzer—the samples were diluted at a ratio of 1 to 250 and 1 to 500, respectively. Analysis against the calibration curve of Latex 2B revealed that about 79% of the latex was adsorbed to the pigment.
[0101] The energy consumption of the high shear forces mixing stage was, for the first mixer, 10 kWh/t and for the second mixer 5.5 kWh/t. In the second, conventional mixing stage the energy consumption was about 6.5 kWh/t. Here the low energy consumption of the conventional mixing stage is caused by the fact that the slurry was already extremely well dispersed after the two first Atrex steps.
Example 4
[0102] This example illustrates dispersing of an inorganic pigment using a latex grafted with dispersing agent K5 and mixed with a Diaf mixer (cf. FIG. 5 ).
[0103] First, 9,576 g wet, undispersed PCC pigment (Opacarb A40, supplied by Special Minerals Inc, Äänekoski, Finland) was weighed. The pigment was supplied in the form of a wet filter cake having a solid content of 67.9%, and the weighed amount therefore equaled 6,500 g dry pigment. Then, 9 parts of a modified latex (Latex 2B) was weighed against the dry pigment. Latex 2B comprised an SB latex of type Litex PX 9292, which had been modified by grafting 5 parts of dispersing agent K5 onto the SB latex polymer. The weighed amount of the modified latex was 1440 g wet Latex 2B, having a solids content of 40.6%.
[0104] All the modified latex Latex 2B blend was placed in a 10 L round bottom stainless steel container 41 . Addition of Opacarb A40 into the container was initiated progressively by mixing the Latex 2B with a Diaf FFB H3 dissolver equipped with Type-3 blade, diameter 4″ from Blade Shop Inc. (at 36 m/s radial velocity). After an addition of about 80% of the wet undispersed filter cake (about 7,660 g), the slurry turned very thick (toothpaste like). Dispersing agent K5 was separately added in an amount of 0.3 parts (per 100 parts of dry pigment, which amounts to 45.9 g wet dispersing agent with a solid content of 42.5%) to restore the flowability of the slurry.
[0105] The rest of the undispersed pigment, about 1,900 g wet filter cake, was then added into the container. The slurry remained flowable in spite of this addition. The pH of the slurry was 8.8 without adjustment. Temperature was monitored (ref. numeral 42 ) and samples taken via valve 43 .
[0106] The high shear viscosity of the slurry was measured with an ACAV-A2 Automated Ultra High Shear Viscometer by using 0.6×50 mm capillary at 25 [ACA Systems Oy, Outilantie 3, 83750 Sotkuma, Finland]. The viscosity value at the shear rate value 135,000 s −1 was 433 mPas. The static water retention was evaluated for slurry with an AA-GWR Water Retention meter measuring 30 s with 0.30 bar at 25° C. [Kaltec Scientific, Inc., 22425 Heslip Drive, Novi, Mich. 48375 , USA]. The value was 137 g/m 2 .
[0107] The energy intensity of the mixing stage was 160 kWh/m 3 and the energy consumption about 135 kWh/t. The dispersing (mixing) time in the Diaf was 45 minutes.
[0108] The slurry was centrifuged with a Sorvall Instruments RC5C centrifuge equipped with an SS-34 rotor for 40 min at 26,500 G and 25° C. The latex content of liquid phase was then analyzed with a Shimadzu TOC-V CPH Total Organic Carbon (TOC) analyzer—the samples were diluted at a ratio of 1 to 250 and 1 to 500, respectively. Analysis against the calibration curve of Latex 2B revealed that about 29% of the latex was adsorbed to the pigment.
Example 5
[0109] This example illustrates dispersing of inorganic pigment using a latex grafted with dispersing agent K5. The slurry is directed twice through an Atrex impact mixer and then post-mixed with a Diaf mixer, additional dispersing agent being added.
[0110] The configuration of the process is depicted in FIG. 5 , wherein reference numerals 51 and 52 are used for high-shear forces mixers, 53 for a post-mixer and 54 and 55 for temperature control and sampling valves, respectively.
[0111] First, 10,477 g wet, undispersed PCC pigment (Opacarb A40, supplied by Special Minerals Inc, Äänekoski, Finland) was weighed. The pigment was supplied in the form of a wet filter cake having a solid content of 66.8%, and the weighed amount therefore equalled 7,000 g dry pigment. Then, 9 parts of a modified latex (Latex 2B) was weighed against the dry pigment. Latex 2B comprised SB latex of type Litex PX 9292, which had been modified by grafting 5 parts of dispersing agent K5 onto the SB latex polymer. The weighed amount of the modified latex was 1,551 g wet Latex 2B, having a solids content of 40.6%.
[0112] Opacarb A40 and Latex 2B were fed into the dispersing chamber of an Atrex CD350 impact mixer 51 by constant ratio. The resultant thick paste was carried by gravity to the next identical Atrex unit 52 . In the both cases the operating rate was 1,200 rpm denoting 21.5 m/s radial velocity for the outermost rim and the temperature was a. 35° C.
[0113] In the two Atrex mixers, the material was subjected to an energy intensity of about 1535 kWh/m 3 and 830 kWh/m 3 , respectively. The feed rates were 830 g/s and pass times 13 s in both.
[0114] Finally the slurry (toothpaste like) was carried by gravity into a 10 L round bottom stainless steel container 53 and mixed with a Diaf FFB H3 dissolver equipped with Type-3 blade, diameter 4″ from Blade Shop Inc. (at 36 m/s radial velocity). Dispersing agent K1 was added in an amount of 0.1 parts (per 100 parts of dry pigment, which amounts to 16.1 g wet dispersing agent with a solid content of 43.5%) to induce the flowability of the slurry. The pH of the slurry was 8.8 without adjustment. Dispersing agent K1 is an anionic dispersing agent which is based on 100 mole-% acrylic acid and supplied by Kemira Oyj, Finland. Compared to K5, it has a lower charge density, amounting to about 14.1 meq/g. The average molecular weight of K1 is M w 15,100.
[0115] The high shear viscosity of slurry was measured with an ACAV-A2 Automated Ultra High Shear Viscometer by using 0.6×50 mm capillary at 25° C. [ACA Systems Oy, Outilantie 3, 83750 Sotkuma, Finland]. The viscosity value at the shear rate value 135,000 s −1 was 155 mPas. The static water retention was evaluated for slurry with an AA-GWR Water Retention meter measuring 30 s with 0.30 bar at 25° C. [Kaltec Scientific, Inc., 22425 Heslip Drive, Novi, Mich. 48375, USA]. The value was 124 g/m 2 .
[0116] The slurry was centrifuged with a Sorvall Instruments RC5C centrifuge equipped with an SS-34 rotor for 40 min at 26,500 G and 25° C. The latex content of liquid phase was then analyzed with a Shimadzu TOC-V CPH Total Organic Carbon (TOC) analyzer—the samples were diluted at a ratio of 1 to 250 and 1 to 500, respectively. Analysis against the calibration curve of Latex 2B showed that about 94% of the latex was adsorbed to the pigment, which—when compared with Example 3—indicates the benefit of using a dispersing agent having a lower charge density for adjusting the viscosity of the mixed slurry than for modifying the latex.
[0117] The energy consumption of the high shear forces mixing stage was, for the first mixer, 10.5 kWh/t and for the second mixer 5.7 kWh/t. In the conventional mixing stage the energy consumption was about 2.3 kWh/t which is lower than in Example 3 and which may indicate that dispersant K1 is more efficient than K5. | A method of producing a stable aqueous dispersion of a latex, solid particles and a dispersing agent, comprising contacting the latex with an anionic dispersing agent to form a modified latex, feeding the modified latex and the solid particles to a zone of high shear forces, and simultaneously subjecting essentially all of the modified latex and the solid particles fed to said zone to high shear forces to form a latex-particle slurry. By means of the invention, over 60 wt-% of the latex can be adsorbed on the solids. Latex immobilization increases the surface strength of final coating layer and allows for a decrease of latex consumption in paper and cardboard and paint applications. | 2 |
This is a divisional application of application Ser. No. 07/537,904 filed Jun. 12, 1990 now U.S. Pat. No. 5,095,100.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a new metal complex dye used mainly for leather dyeing, a method of its production and a metal-tanned leather dyeing method using said metal complex dye.
2. Description of the Prior Art
The majority of dyes used for leather dyeing are anionic dyes having a water-soluble group, such as acid dyes, direct dyes, metal complex dyes and mordant dyes. For dyeing chromium-tanned leather and other highly cationic leather, dyes having a sulfo group have conventionally been used in almost all cases.
For example, Japanese Patent Publication Open to Public Inspection Nos. 40357/1983, 59871/1981, 171776/1982, 171778/1982 and 259685/1985 propose metal complex dyes with the aim of improving various properties including color fastness to rubbing, color fastness to water, color fastness to washing, color fastness to light, dyeing property, leveling property and permeability. These dyes all have a sulfo group or a carboxyl group as a water-soluble group.
However, the dyes and dyeing methods which have conventionally been used to dye leather, particularly metal-tanned leather, are not fully satisfactory with respect to dyeing power, color fastness to rubbing and permeability.
The present invention was developed in consideration of these aspects. The object of the invention is to provide a metal complex dye that offers good permeability and excellent color fastness to rubbing and color fastness to light particularly in metal-tanned leather dyeing, a method of its production and a metal-tanned leather dyeing method.
SUMMARY OF THE INVENTION
The object described above is accomplished by metal complex dyes comprising one of metalizable azo compounds respectively represented by Formulas [I] through [IV] shown below: ##STR1## In Formulas [I] through [IV], Ps represents a phosphono group in the form of a free acid or a salt; Sf represents a sulfo group in the form of a free acid or a salt; m is 0, 1 or 2. R 1 represents a hydrogen atom or an amino group; X represents a hydroxyl group, an alkoxy group having a carbon number of 1 or 2 or a carboxyl group. Y represents a hydroxyl group, an alkoxy group having a carbon number of 1 or 2, a carboxyl group or a methyl group; R 2 represents a hydrogen atom or a hydroxyl group; A represents a phenyl group or naphthyl group selected from the group comprising the following 1 through 4: ##STR2## In the above formulas 1 through 4, Sf has the same definition as above; n is 0, 1 or 2. R 3 represents a hydroxyl group or a carboxyl group; R 4 represents a hydroxyl group, a carboxyl group or an amino group; R 5 and R 6 independently represent a hydroxyl group or a carboxyl group; R 7 and R 8 independently represent a hydrogen atom, a hydroxyl group or an amino group. B has the same definition as A above except that R 3 represents a hydroxyl group, a carboxyl group or an amino group. R 9 represents a hydrogen atom, a methyl group, an alkoxy group having a carbon number of 1 or 2 or a sulfo group in the form of a free acid or a salt; D represents a coupling component residue having a metalizable hydroxyl group at the position adjoining to the azo group.
Note that in the present specification "the position adjoining to the azo group" means "the second position as counted from the carbon atom bound with the azo group."
Also, the metal-tanned leather dyeing method of the present invention to accomplish the object described above comprises dyeing metal-tanned leather with a metal complex dye comprising a metalizable azo compound represented by one of Formulas [I] through [IV] shown above.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The metal complex dye of the present invention described above can be obtained by metalizing a disazo compound, trisazo compound or tetrakisazo compound represented by one of Formulas [I] through [IV] shown above. Examples of metal complex dyes comprising a metalizable azo compound represented by Formula [I] include those having a structure like the following Formula [a]: ##STR3##
Examples of metal complex dyes comprising a metalizable azo compound represented by Formula [II] include those having a structure like the following Formulas [b] through [d]: ##STR4##
Examples of metal complex dyes comprising a metalizable azo compound represented by Formula [III] include those having a structure like the following Formulas [e] through [h]: ##STR5##
Examples of metal complex dyes comprising a metalizable azo compound represented by Formula [IV] include those having a structure of the following Formula [i]: ##STR6## In Formulas [a] through [i], Ps, Sf, R 1 , R 2 , R 4 , R 7 , R 8 , R 9 , X, Y, D, m and n have the same definitions as above. Z represents --O-- or --COO--; Me represents a metal such as copper, nickel, cobalt, iron or chromium. The metalizable hydroxyl group in D is represented by --O-- when metalized.
Concerning the metal Me, at most two atoms thereof are coordinated per compound molecule in most cases in compounds of Formula [I] and [III], but metal complex dyes wherein either atom alone is coordinated are included in the scope of the present invention.
In the present invention, Ps is a phosphono group that has substituted at the o-, m- or p-position to the azo group, and exists in the form of a free acid or a salt.
If this phosphono group is represented by --P (═O) (OM) 2 , M will be hydrogen when the phosphono group is in the form of a free acid, and M will be an alkali metal such as sodium, potassium or lithium, an ammonium such as NH 4 or an amine such as alkanolamine when the phosphono group is in the form of a salt.
Also, the dye of the present invention may have a sulfo group.
In this case, the sulfo group takes the form of a free acid or a salt like the phosphono group described above.
If this sulfo group is represented by --SO 3 M, M will be hydrogen when the sulfo group is in the form of a free acid, and M will be an alkali metal, an ammonium or an amine when the sulfo group is in the form of a salt.
In the dye of the present invention, the M units contained in the one or two phosphono groups and one or two or more sulfo groups may be identical with each other or not.
A metalizable azo compound represented by Formula [I] shown above can be obtained by reacting the diazonium salt of o-, m- or p-aminobenzenephosphonic acid with a naphthol that forms Formula [V]: ##STR7## wherein R 1 , Sf and m have the same definitions as above, or a sulfonic acid derivative thereof, under acidic conditions to yield a monoazo compound represented by Formula [VI]: ##STR8## wherein R 1 , Ps, Sf and m have the same definitions as above, and subsequently coupling the monoazo compound with the tetrazonium salt of a benzidine derivative represented by Formula [VII]: ##STR9## wherein X has the same definition as above, under alkaline conditions.
A metal complex dye comprising a metalizable azo compound represented by Formula [II] shown above can be obtained by reacting the tetrazonium salt of a benzidine derivative represented by Formula [VIII]: ##STR10## wherein Y has the same definition as above, with a coupler that forms Formula [IX]: ##STR11## wherein R 2 , Sf and m have the same definitions as above, under acidic conditions to yield a compound represented by Formula [X]: ##STR12## wherein Y, R 2 , Sf and m have the same definitions as above, followed by reaction of the compound with the diazonium salt of o-, m- or p-aminobenzenephosphonic acid under alkaline conditions, and subsequently further reacting the reaction product with a coupler that forms A (A has the same definition as above) preferably under neutral conditions.
A metalizable azo compound represented by Formula [III] shown above can be obtained by reacting the tetrazonium salt of a benzidine derivative represented by Formula [VII] shown above with a coupler that forms B (B has the same definition as above) under acidic, neutral or alkaline conditions, and subsequently reacting the reaction product with a monoazo compound represented by Formula [VI] shown above.
A metalizable azo compound represented by Formula [IV] shown above can be obtained by coupling the diazonium salt of o-, m- or p-aminobenzenephosphonic acid with an aniline or aminobenzene derivative having substituents X and R 9 (X and R 9 have the same definitions as above) to yield a monoazo compound represented by Formula [XI]: ##STR13## wherein Ps, X and R 9 have the same definitions as above, and subsequently reacting the diazonium salt of the monoazo compound with a coupler that forms a coupling component residue D (D has the same definition as above).
Examples of compounds selected as appropriate for the production of azo compounds of Formulas [I] through [IV] shown above.
The aminobenzenephosphonic acid may be o-, m- or p-aminobenzenephosphonic acid, with preference given to m-or p-aminobenzenephosphonic acid.
Examples of benzidine derivatives include 3,3'-dihydroxybenzidine, 3,3'-dimethoxybenzidine, 3,3'-diethoxybenzidine, 3,3'-dicarboxybenzidine and 3,3'-dimethylbenzidine.
Examples of the coupling component that forms Formula [V] include H-acid, S-acid and K-acid.
Examples of the coupling component that forms Formula [IX] include H-acid, S-acid and K-acid.
Examples of the coupler that forms A include m-hydroxybenzoic acid, m-aminophenol, m-phenylenediamine, pyrocatechol, salicylic acid, H-acid, S-acid, K-acid, M-acid, chromotropic acid, J-acid, 2R-acid, R-acid, NW-acid and Schaffer's acid.
Examples of the coupler that forms the coupling component residue D (hereinafter referred to as coupler D) include β-naphthols, α-naphthols, pyrazolones, phenols and acetoacetic anilide derivatives.
Examples of substances preferable for the coupler D include naphthols such as 8-amino-2-naphthol, Schaffer's acid, R-acid, G-acid, γ-acid, H-acid, J-acid, S-acid, SS-acid, L-acid, M-acid, 2R-acid, NW-acid and K-acid and sulfonic acid derivatives thereof; pyrazolones such as 3-methyl-5-phenylpyrazolone and derivatives thereof; phenols such as resorcinol, cresol and p-phenylphenol; and acetoacetic anilide.
Examples of the aniline or aminobenzene derivative having substituents X and R 9 described above include cresamine, p-cresidine, o-anisidine, o-phenetidine, 2,5-dimethoxyaniline, 3-amino-4-hydroxybenzenesulfonic acid and anthranilic acid.
A metal complex dye of the present invention can be obtained by reacting an azo compound described above with a metal provider in water and/or an organic solvent under acidic or basic conditions. Metalization for this purpose can be carried out by a method known per se, e.g. the method described in Japanese Patent Publication Open to Public Inspection No. 40357/1983.
Specifically, it can be obtained by carrying out reactin at 70° to 150° C. in water and/or an organic solvent under acidic or basic conditions in the presence of a metal provider added in a given ratio per mol of a metalizable polyazo compound represented by one of Formulas [I] through [IV] until the compound becomes completely unrecognizable.
The amount of the metal provider used varies according to the compound, but if the number of metal atoms coodinated per compound molecule is written q, it is preferable that the amount of the metal be (1.0 to 1.5)×q gram atom.
In accordance with the production method described above, a copper, nickel, cobalt, iron or chromium complex dye comprising a metalizable azo compound represented by Formula [I] or Formula [III] is obtained as a metal complex dye wherein 1 or 2 metal atoms are coordinated per compound molecule. Also, a copper or nickel complex dye comprising a metalizable azo compound represented by Formula [IV] is obtained as a 1:1 type complex dye, and a cobalt, iron or chromium complex dye is obtained as a 1:1 type and/or 1:2 type complex dye.
The resulting metal complex dye can be isolated by a direct means such as spray drying or drum drying, or acidization or salting-out. Also, the metal complex dye can be obtained as a desired amine salt by treating the acidization product with amine.
Examples of solvents which can be used for metalization include water-soluble organic solvents such as formamide or dimethylformamide and glycols or monoalkyl ethers thereof.
Examples of metal providers which can be used include the copper, nickel, cobalt, iron or chromium salt of organic or inorganic acid. Examples of copper providers include copper sulfate, copper chloride, copper acetate, copper formate and copper carbonate. Examples of nickel providers include nickel sulfate, nickel chloride, nickel acetate and nickel formate. Examples of other usable metal providers include cobalt acetate, cobalt chloride, ferric chloride, chromium acetate, chromium formate, chromium sulfate and chromium salicylate.
Metalization is preferably carried out in the presence of the carbonate of an alkali metal or alkaline earth metal, or ammonia or a lower amine.
In the production method described above, when the substituent X or Y in the azo compound is an alkoxy group having a carbon number of 1 or 2, it is preferable to carry out metalization in an organic solvent.
The new metal complex dye having a phosphono group thus obtained can be used for dyeing by a processing method similar to that for conventional acid dyes at a temperature of about 50° C. and pH 3 to 6 as needed for leather dyeing.
An ordinary dyeing process can be used for the process of dyeing metal-tanned leather.
The types of metal tanning of leather to be dyed include aluminum tanning, titanium tanning and zirconium tanning as well as chromium tanning.
An example of the dyeing process is given below.
Chrome-tanned leather shaven to a given thickness is subjected to washing and neutralization for pretreatment processes, and then dyed. Formic acid is added for fixation, followed by stuffing and neutralization.
The washing process for pretreatment is carried out to remove the unbound portion of the tanning agent from the leather, remove the unbound portion of the acid from the leather, remove the foreign matter adhering to the leather, defiber the leather texture and for other purposes, and can be achieved by running water washing using a drum.
The neutralization process for pretreatment is carried out to neutralize the collagen that cannot be removed from the leather by washing alone and the acid bound to the chromium complex to uniformize the penetration of the dye and stuffing agent, and can be achieved by neutralization treatment at pH 5 to 6 for 30 minutes to 2 hours using a neutralizing agent such as an alkaline or weakly alkaline base.
Examples of neutralizing agents include sodium bicarbonate, sodium acetate and sodium formate.
Dyeing is carried out by drum dyeing, paddle dyeing, etc. using a dye for the method of the present invention to obtain the desired color. Drum dyeing can be carried out by treatment with a dye solution being added while rotating the drum at pH 4.5 to 6.0 for a given period using water (50° to 60° C.) in a ratio of 190 to 300% to the shaving weight.
Stuffing can be carried out by adding a stuffing agent to a fresh bath after dyeing. Examples of usable stuffing agents include nonionic, anionic and cationic stuffing agents as well as raw oils and synthetic oils and fats.
This method is applicable to leather subjected to secondary tannin tanning after chromium tanning and leather subjected to secondary chromium tanning after tannin tanning, as well as leather tanned with chromium alone such as wet blue. It does not matter of what type the leather is, such as cow skin, pig skin, horse skin, sheep skin, goat skin, etc., as long as it has been subjected to chromium tanning. This method is also applicable to aluminum-tanned leather, titanium-tanned leather and zirconium-tanned leather.
The mechanism of the action of the metal complex dye of the present invention on metal-tanned leather dyeing remains unclarified, but it is speculated that the dye of the present invention offers excellent color fastness to rubbing and good permeability in comparison with conventional dyes containing a sulfo group or a carboxyl group because the phosphono group contained in the dye of the present invention bounds to a metal such as chromium ion in metal-tanned leather by coorinate bond or reaction, and in addition, color fastness to light improves because a metal complex structure stable to light is formed due to metalization.
The metal complex dye of the present invention shows good permeability to metal-tanned leather, and metal-tanned leather dyed with the metal complex of the present invention offers excellent color fastness to rubbing in comparison with acid dyes and other dyes having no phosphono group and excellent color fastness to light in comparison with dyes having a phosphono group.
The present invention is hereinafter described in more detail by means of the following examples, but the invention is not by any means limited by them, as long as the gist of the invention is not overstepped.
[Synthesis of Metalizable Azo Compounds]
Synthesis Example 1
104 g (0.6 mol) of 3-aminobenzenephosphonic acid was dissolved in an aqueous solution of 90 g of concentrate hydrochloric acid in 400 ml of water. The resulting solution was cooled to 0° C. with ice, followed by diazotization using an aqueous solution of 42 g of sodium nitrite. After the excess portion of nitrous acid in the resultant diazonium salt solution was decomposed with sulfamic acid, 30 g of urea was added to the diazonium salt solution, followed by stirring at 0° C. for 30 minutes.
Separately, 191 g (0.6 mol) of H-acid was completely dissolved in 1500 ml of water. This solution, after being adjusted to pH 6.5 to 7.0 with sodium carbonate, was added to the above-mentioned diazonium salt solution. Then, 50 g of sodium acetate was added, followed by adjustment to pH 3 with an aqueous solution of sodium carbonate and stirring at 0° to 10° C. overnight to yield a monoazo compound solution.
Then, 65 g (0.3 mol) of 3,3'-dihydroxybenzidine was dissolved in an aqueous solution of 90 g of concentrate hydrochloric acid in 500 ml of water. The resulting solution was cooled to 0° C. with ice, followed by tetrazotization using an aqueous solution of 42 g of sodium nitrite. This solution was added to the above-mentioned monoazo compound solution. After stirring at pH 8 to 9 and 0° to 8° C. for 5 hours, the mixture was heated to 60° C. and filtered, washed and dried to yield 350 g of a tetrakisazo compound (Compound Example 1; Compound Examples will be described later in the form of free acids.)
Synthesis Example 2
28 g (about 0.1 mol) of benzidine-3,3'-dicarboxylic acid was added to 600 ml of water, and dissolved while heating at 60° C. in the presence of sodium carbonate. To this solution, 30 g of hydrochloric acid was added. This mixture was cooled to 2° C. with ice, followed by tetrazotization using an aqueous solution of 15 g of sodium nitrite. Then, 20 g of urea was added, followed by stirring for a while.
Separately, 32 g of H-acid was dissolved in 150 ml of water while heating at 60° C. This solution, after being adjusted to pH 7 with an aqueous solution of sodium carbonate, was added to the above-mentioned tetrazotized product. After stirring at 0° to 10° C. overnight while maintaining pH 3.0 to 3.5 with an aqueous solution of sodium carbonate, this monoazo solution was adjusted to pH 8.5 with an aqueous solution of sodium carbonate. To this solution, 17.5 g (0.1 mol) of 3-aminobenzenephosphonic acid as diazotized by a standard emthod was added, followed by stirring at pH 8.5 for 4 hours. Then, 11 g (0.1 mol) of resorcinol was added, followed by stirring for 15 hours. This mixture was acidized by the addition of hydrochloric acid and heated to 70° C., followed by filtration to yield 500 g of a cake containing a trisazo compound (Compound Example 3).
Synthesis Example 3
17.3 g (0.1 mol) of 3-aminobenzenephosphonic acid was dissolved in an aqueous solution of 20 g of concentrate hydrochloric acid in 100 ml of water. The resulting solution was cooled to 0° C. with ice, followed by diazotization using an aqueous solution of 7 g of sodium nitrite. After the excess portion of nitrous acid in the resultant diazonium salt solution was decomposed with 10 g of urea, an aqueous solution of 31.9 g (0.1 mol) of H-acid adjusted to pH 7 with sodium carbonate was added to the diazonium salt solution, followed by stirring at pH 3.0 to 3.5 for 24 hours. This mixture was adjusted to pH 8 with sodium carbonate, and dissolved completely to yield a monoazo compound solution.
Separately, 24.4 g (0.1 mol) of 3,3'-dimethoxybenzidine was tetrazotized by the method described above, followed by the addition of 10 g of urea and stirring for a while. To this tetrazonium salt solution, a solution of 11 g (0.1 mol) of resorcinol was added, followed by stirring at pH 5 for 2 hours. Then, the above-mentioned monoazo compound solution was added. After stirring at pH 8 to 8.5 for 5 hours, this mixture was subjected to acidization and salting-out using dilute hydrochloric acid, followed by filtration, washing and drying to yield 90 g of a trisazo compound (Compound Example 9).
Synthesis Example 4
104 g (0.6 mol) of 3-aminobenzenephosphonic acid was dissolved in an aqueous solution of 90 g of concentrate hydrochloric acid in 400 ml of water. The resulting solution was cooled to 0° C. with ice, followed by diazotization using an aqueous solution of 42 g of sodium nitrite. After the excess portion of nitrous acid in the resultant diazonium salt solution was decomposed with sulfamic acid, 30 g of urea was added to the diazonium salt solution, followed by stirring at 0° C. for 30 minutes. Then, a solution of 83 g (0.6 mol) of p-cresidine in a mixture of 2000 ml of water and 72 g of aqueous hydrochloric acid was gradually added to the diazonium salt solution, followed by stirring at 5° to 10° C. overnight. The reaction mixture was filtered and washed. The cake thus obtained (monoazo compound represented by Formula [IV]) was dispersed in 4000 ml of water, followed by the addition of 120 g of hydrochloric acid and stirring. Then, after diazotization using an aqueous solution of 42 g of sodium nitrite at 30° to 40° C., 30 g of urea was added, followed by stirring for a while. Then, an aqueous solution of both 96 g (0.6 mol) of 1-amino-7-naphthol and 60 g of sodium hydroxide in 1200 ml of water was prepared. To this solution, the above-mentioned monoazo compound diazonium salt solution was added, followed by stirring at pH 8.0 to 8.5 for 4 hours. Then, this mixture was acidized to pH 4 with dilute hydrochloric acid and heated to 70° C., followed by filtration, washing and drying to yield 250 g of a disazo compound (Compound Example 11).
[Synthesis of Metal Complex Dyes]
Example 1 (Copper Complex Dyes)
125 g (about 0.1 mol) of the compound obtained in Synthesis Example 1 (Compound Example 1) was added to 2000 ml of water. To this mixture, 50 g of copper sulfate (CuSO 4 .5H 2 O) (Cu: about 0.2 gram atom) in 200 ml of warm water and then 100 g of ammonia were added, followed by stirring at pH 7.0 to 8.0 and 70° to 80° C. for 24 hours. After confirmation of the absence of unreacted compound, 100 g of ammonium chloride salt was added, followed by filtration, washing and drying to yield 170 g of a copper complex dye (Dye Example 1; Dye Examples will be given in Table 1 shown below; the colors shown in the table are those in the leather to be dyed.)
Example 2 (Nickel Complex Dye)
125 g (about 0.1 mol) of the compound obtained in Synthesis Example 1 (Compound Example 1) was treated with 50 g of nickel acetate (Ni(CH 3 COO) 2 .4H 2 O) in the same manner as Example 4 to yield a nickel complex dye (Dye Example 2).
Example 3 (Copper Complex Dye)
500 g of the wet cake containing the compound (Compound Example 3) obtained in Synthesis Example 2 was diluted with 3000 ml of water. After heating to 90° C., 30 g of copper sulfate (CuSO 4 .5H 2 O) (Cu: about 0.2 gram atom) in 100 ml of warm water and then 30 g of 25% aqueous ammonia were added, followed by stirring at pH 7.0 to 8.0 and 80° to 90° C. for 20 hours. After confirmation of the absence of unreacted compound, 100 g of ammonium chloride was added, followed by filtration, washing and drying to yield 97 g of a copper complex dye (Dye Example 5).
Example 4 (Copper Complex Dye)
To 500 ml of ethylene glycol, 45 g (about 0.05 mol) of the compound obtained in Synthesis Example 3 (Compound Example 9) and 20 g of 30% aqueous ammonia were added, followed by the addition of 20 g of copper acetate (Cu(CH 3 COO) 2 .H 2 O) and stirring at 95° to 100° C. until there was no unreacted compound. Then, about 500 ml of warm water and 100 g of NH 4 Cl were added. After salting-out, the mixture was filtered and dried to yield 50 g of a copper complex dye (Dye Example 11).
Example 5 (cobalt complex dye)
45 g (about 0.05 mol) of the compound obtained in Synthesis Example 3 (Compound Example 9) was treated with 30 g of cobalt sulfate (CoSO 4 .7H 2 O) in the same manner as Example 7 to yield a cobalt complex dye (Dye Example 12).
Example 6 (chromium complex dye)
30 g of chromium formate (Cr(HCOO) 2 ) was completely dissolved in 2000 ml of water. To this solution, 125 g (about 0.1 mol) of the compound obtained in Synthesis Example 1 (Compound Example 1) and sodium acetate were added, followed by stirring at pH 4 to 5 and 70° to 80° C. for 30 hours. Then, the mixture was treated with 15 g of ethanolamine, followed by filtration, washing and drying to yield 200 g of a chromium complex salt (Dye Example 4) in the form of an ethanolamine salt.
Examples 7 through 13
The compounds of Compound Examples 2, 4, 5, 6, 7, 8 and 10 described below were each metalized with copper sulfate to yield copper complex dyes (Dye Examples 3, 6, 7, 8, 9, 10 and 13).
Example 14 (copper complex dye)
30 g of copper sulfate (CuSO 4 .5H 2 O) was completely dissolved in 150 g of ethylene glycol. To this solution, 50 g (about 0.1 mol) of Compound Example 11 was added, followed by stirring at 140° to 150° C. for 5 hours. After confirmation of the absence of unreacted compound, 100 g of ammonium chloride and 500 ml of warm water were added, followed by filtration, washing and drying to yield 50 g of a copper complex dye (Dye Example 14).
Example 15 (copper complex dye)
30 g of copper sulfate (CuSO 4 .5H 2 O) was dissolved in 150 g of ethylene glycol. To this solution, 50 g of ammonia and then 56 g (about 0.1 mol) of Compound Example 16 were added, followed by stirring at 95° to 100° C. for 15 hours. After confirmation of the absence of unreacted compound, 100 g of ammonium chloride and 500 ml of warm water were added, followed by salting-out, filtration, washing and drying to yield 65 g of a copper complex dye (Dye Example 19).
Example 16 (copper complex dye)
25 g of copper chloride (CuCl 2 .2H 2 O) was completely dissolved in an aqueous solution of 60 g of ammonia in 1000 ml of water. To this solution, 62 g (about 0.1 mol) of Compound Example 14 was added, followed by stirring at 70° to 80° C. until there was no unreacted compound, After addition of 100 g of ammonium chloride and 500 ml of warm water, salting-out was conducted with sodium chloride, followed by filtration and drying to yield 70 g of a copper complex dye (Dye Example 17).
Example 17 (Nickel Complex Dye)
29.8 g of nickel acetate (Ni(CH 3 COO) 2 .4H 2 O) was completely dissolved in 1000 ml of water. To this solution, 56 g (about 0.1 mol) of Compound Example 23 was added, followed by stirring at 70° to 80° C. and pH 5 to 6.5 for 10 hours. After confirmation of the absence of unreacted compound, salting-out was carried out, followed by filtration and drying to yield 65 g of a nickel complex dye (Dye Example 26).
Example 18 (Chromium Complex Dye)
25 g of chromium acetate (Cr(CH 3 COO) 3 .H 2 O) was completely dissolved in 800 ml of water while heating. To this solution, 64 g (about 0.1 mol) of Compound Example 17 was added, followed by stirring at 70° to 80° C. and pH 5 to 6.5 until there was no unreacted compound. After salting-out with sodium chloride, this solution was filtered and dried to yield 65 g of a chromium complex dye (Dye Example 20).
Example 19 (Cobalt Complex Dye)
30 g of cobalt sulfate (CoSO 4 .7H 2 O) was completely dissolved in an aqueous solution of 60 g of ammonia in 1000 ml of water. To this solution, 56 g (about 0.1 mol) of Compound Example 12 was added, followed by stirring at 70° to 80° C. and pH 7 to 8 until there was no unreacted compound. This mixture was then treated with 8 g of ethanolamine and filtered, washed and dried to yield 67 g of a cobalt complex dye (Dye Example 15) in the form of an ethanolamine salt.
Examples 20 Through 30
The compounds listed in the column for compounds in Table 1 were treated in the same manner as above to yield metal complex dyes (Dye Examples 13, 15, 18 through 22 and 24 through 27) respectively comprising the metals listed in the column for metals in the same table. ##STR14##
TABLE 1______________________________________(Dye Examples)Dye (No.) Compound (No.) Metal Color______________________________________ 1 (1) Copper Black 2 (1) Nickel Black 3 (2) Copper Black 4 (1) Chromium Black 5 (3) Copper Black 6 (4) Copper Black 7 (5) Copper Black 8 (6) Copper Black 9 (7) Copper Black10 (8) Copper Black11 (9) Copper Black12 (9) Cobalt Black13 (10) Copper Black14 (11) Copper Black15 (12) Cobalt Red16 (13) Copper Purple17 (14) Copper Black18 (15) Copper Black19 (16) Copper Purple20 (17) Chromium Blue21 (18) Copper Blue22 (19) Copper Blue23 (20) Nickel Purple24 (21) Cobalt Red25 (22) Copper Yellow26 (23) Nickel Yellow27 (24) Copper Orange28 (25) Iron (II) Brown29 (26) Copper Brown30 (27) Copper Yellow______________________________________
Examples 31 through 60
[Chromium-tanned leather dyeing with metal complex dyes of the present invention (Dye Examples 1 through 30)]
For pretreatment, wet blue (chromium-tanned cow skin, leather of 1 mm in thickness for clothing) was washed with running water, after which it was subjected to neutralization treatment with an aqueous solution of sodium bicarbonate at pH 5 to 6 while maintaining a temperatue between 30° and 40° C. Then, the wet blue was subjected to drum dyeing at 60° C. for 30 minutes using a dye listed in Table 1 in a ratio of 2% to the weight of the above-mentioned wet blue and 190% of water. Note that when the water-soluble group of the dye was in the form of a free acid, the dye was previously dissolved in aqueous ammonia and used as a dye solution. After dyeing, formic acid was added for fixation. Further, water in a ratio of 250% to the weight of the wet blue was added, and the temperature was increased to 60° C. Then, 1.4% neutral oil (leather stuffening oil, produced by Yoshikawa Seiyu Co.) and 5.6% synthetic oil (MMP, produced by Orient Chemical Industries, Ltd.) as stuffening agents were added, followed by treatment for 60 minutes. Finally, formic acid was added for neutralization to yield a dyed leather.
The color fastness to rubbing and permeability of the leathers thus obtained are shown in Table 2. The leathers all showed a good leveling property. The color fastness to light was determined by applying each sample to a fademeter (carbon arc type) and making comparisons with the ordinary status using a blue scale (JIS L0841). The duration of fademeter application was 80 hours in Examples 31 through 43 and 40 hours in Examples 44 through 60. The data on color fastness to rubbing shown in the table were obtained in a wet rubbing test using a resonance type rubbing tester in accordance with the standard rubbing test procedure (JIS L0849). Permeability was rated by observation of a cross section of each dyed leather.
To examine for phosphono group and differences in the effects of metallization, comparison experiments were performed as follows:
Comparison Example 1
A black dyed leather was obtained in the same manner as Example 31 except that the metal complex dye of Dye Example 1 was replaced with the corresponding tetrakisazo compound of Compound Example 1 (Comparison Dye q). The results of testing are shown in Table 3 below.
Comparison Example 2
A black dyed leather was obtained in the same manner as Example 35 except that the metal complex dye of Dye Example 5 was replaced with the corresponding trisazo compound of Compound Example 3 (Comparison Dye r). The results of testing are shown in Table 3 below.
Comparison Example 3
A black dyed leather was obtained in the same manner as Example 41 except that the metal complex dye of Dye Example 5 was replaced with the corresponding trisazo compound of Compound Example 9 (Comparison Dye s). The results of testing are shown in Table 3 below.
Comparison Example 4
Black dyed leather was obtained in the same manner as Examples 31 through 43 using a dye represented by the following structural formula (t) (Comparison Dye t). The results of testing are shown in Table 3 below. ##STR15##
Comparison Example 5
A black dyed leather was obtained in the same manner as Example 44 except that the metal complex dye of Dye Example 14 was replaced with the corresponding disazo compound of Compound Example 11 (Comparison Dye u). The results of testing are shown in Table 3 below.
Comparison Example 6
A black dyed leather was obtained in the same manner as Example 47 except that the metal complex dye of Dye Example 17 was replaced with the corresponding disazo compound of Compound Example 14 (Comparison Dye v). The results of testing are shown in Table 3 below.
Comparison Example 7
Red dyed leather was obtained in the same manner as Examples 44 through 60 using a dye represented by the following structural formula (w) (Comparison Dye w). The results of testing are shown in Table 3 below. ##STR16##
Comparison Example 8
Using a dye represented by the following structural formula (x) (Comparison Dye x), dyeing was carried out in the same manner as Examples 44 through 60. The results of testing are shown in Table 3 below. ##STR17##
TABLE 2______________________________________Dye Color fastness Color fastnessExample to light to rubbing Permia-(No.) (grade) (grade) bility______________________________________Examples31 1 8 5 ⊚32 2 8 5 ⊚33 3 8 5 ⊚34 4 7-8 5 ⊚35 5 6 5 ⊚36 6 7 5 ⊚37 7 7 5 ⊚38 8 7 5 ⊚39 9 7 5 ◯40 10 5-6 5 ◯41 11 7 5 ⊚42 12 7 5 ⊚43 13 6-7 5 ⊚44 14 6 5 ◯45 15 5 5 ⊚46 16 6 4 ⊚47 17 5 4 ⊚48 18 6 5 ⊚49 19 5 5 ⊚50 20 6 4 ⊚51 21 7 5 ⊚52 22 6 5 ◯53 23 5 4 ◯54 24 5 5 ⊚55 25 6 5 ◯56 26 5 5 ◯57 27 5 4 ⊚58 28 4 4 ◯59 29 5 5 ⊚60 30 5 5 ⊚______________________________________ Note: ⊚: Excellent ◯: Good
TABLE 3______________________________________ Compar- Color fastness Color fastness ison to light to rubbing Permia- Dye (grade) (grade) bility______________________________________ComparisonExample1 q 5 5 ⊚2 r 4-5 5 ⊚3 s 5 5 ⊚4 t 4 3 ∘5 u 4 4-5 ∘6 v 3 4 ⊚7 w 3 2-3 Δ8 x 3 3 ∘______________________________________ Note: ⊚: Excellent ∘: Good Δ: Slightly poor ×: poor | Use of metal complex dyes comprised of metalizable azo compounds to dye metal-tanned leather which makes possible good permeability and excellent color fastness to rubbing and color fastness to light. | 3 |
This application claims priority to U.S. Provisional Application Ser. No. 60/810,027, filed Jun. 1, 2006.
BACKGROUND OF THE INVENTION
The present invention relates generally to fuel injection systems for engines.
Known diesel fuel injection systems include a bank of open coils and a bank of close coils. Charging circuits charge the coils to a certain current level and maintain the coil for a certain period of time. Some diesel engines are more difficult to start in very cold weather.
SUMMARY OF THE INVENTION
The present invention provides a circuit for charging coils, particularly suited for a diesel fuel injection system. In an example embodiment of the present invention, the current for some of the coils is increased for a portion of the cycle. An initial pulse is added to the normal charging level of the coils. This provides increased performance during certain conditions, for example, cold weather start-up.
In the example circuitry shown, the level of the pulse is optionally selectable. The controller can select one of a plurality of amplitudes for the pulse.
Optionally, the controller can also control the length of the pulse, by retriggering the pulse. In another optional feature, circuitry for detecting bad coils is modified to accommodate the pulse.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic of the fuel injection system according to one embodiment of the present invention.
FIG. 2 is a schematic of a circuit for detecting a bad coil in the circuit of FIG. 1 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 is a schematic of an example fuel injection coil charging circuit 10 according to one embodiment of the present invention for charging open coils 12 in a diesel fuel injection system. Corresponding close coils 14 are shown and operate normally. As shown in the schematic of FIG. 1 , the inventive feature is applied only to the open coils (even and odd); however, it is possible that it may be desirable to apply the invention to the close coils in certain situations (not shown).
The circuit 10 includes a microcontroller 16 (or other programmable controller or hardware control circuit) suitably programmed to perform normal control functions for the circuit 10 and suitably programmed to perform all of the functions described herein. The circuit 10 further includes a timer, in this example, a one-shot 18 . The one-shot 18 is designed to provide a pulse of predetermined length of time when enabled by the microcontroller 16 (i.e. when the microcontroller does not activate the Reset input) and when the one-shot 18 is activated on its input A. The one-shot 18 input is activated by a NAND gate 20 receiving low-active even and odd outputs from the microcontroller 16 . The one-shot 18 can also be retriggered by a peak delay signal (PKDLY) from the microcontroller 16 to a transistor T D , which can retrigger the one-shot 18 and restart the timing of the one-shot 18 . The one-shot 18 is designed to generate a pulse of a predetermined time. In the example embodiment, that pulse has a time of six hundred microseconds; however, the exact duration can be tailored for the particular application. If additional time is desired in a particular situation, the microcontroller 16 can retrigger the one-shot 18 prior to the end of the first pulse.
The output of the one-shot 18 is connected to four NOR gates N 1 -N 4 . The microcontroller 16 has four outputs PK 1 , PK 2 , PK 3 , PK 4 , each connected to one of the inputs of one of the NOR gates N 1 -N 4 . The output of each NOR gate N 1 -N 4 is connected to the base of two transistors T 1 and T 5 , T 2 and T 6 , T 3 and T 7 , T 4 and T 8 respectively. Each of the transistors T 1 -T 8 has a corresponding resistor R 1 -R 8 which the transistor selectively connects in parallel to Vcc. More particularly, the first four transistors T 1 -T 4 each selectively connect its corresponding resistor R 1 -R 4 in parallel with the other resistors R 1 -R 4 . Similarly, the transistors T 5 -T 8 each selectively connect its associated resistor R 5 -R 8 in parallel with the other resistors R 5 -R 8 .
The resistors R 1 -R 4 provide a branch of a voltage divider circuit 22 associated with the even open coils 12 , while the resistors R 5 -R 8 comprise a branch of a voltage divider circuit 20 associated with the odd open coils 12 . The voltage divider circuits 20 , 22 each further include resistors R A and R B , which provide a voltage input to comparators 24 , 26 , respectively, in driver circuits for the odd and even open coils 12 , respectively. The resistors R 1 -R 4 (when activated by their associated transistors T 1 -T 4 ) are in parallel with resistor R A in the upper half of the voltage divider circuit 20 . The resistors R 5 -R 8 (when activated by their associated transistors T 5 -T 8 ) are in parallel with resistor R A in the upper half of the voltage divider circuit 22 .
Thus, it can be seen that by selectively turning on or off selective combinations of the transistors T 1 -T 4 , selective combinations of the resistors R 1 -R 4 are changing (in this case, raising) the voltage in the voltage divider circuit 22 and, consequently, the resulting voltage input to comparator 24 . Similarly, by selectively turning on or off combinations of the transistors T 5 -T 8 , selective combinations of the resistors R 5 -R 8 are provided to the voltage divider circuit 20 and selectively provide a voltage level input to the comparator 26 . Preferably, although not necessarily, the resistors R 1 -R 4 are all of different values, thus providing sixteen different possible combinations of resistors, and thus, sixteen possible voltage inputs to the comparator 24 . Preferably, the resistance values of resistors R 5 -R 8 are equal to R 1 -R 4 , respectively. Note that transistors T 1 and T 5 are turned on and off simultaneously, while transistors T 2 and T 6 are switched on and off together, as are T 3 /T 7 and T 4 /T 8 . Thus, the voltage supplied to comparator 26 should be equal to the voltage supplied to the comparator 24 .
The comparator 26 will compare the voltage in the odd open coils 12 to the voltage from the voltage divider circuit 22 . The comparator 26 will supply current to the odd open coils 12 until their voltage is equal to that of the voltage divider circuit 22 . When the voltage on the coils 12 decays, the comparator 26 again supplies current until it is equal to the voltage in the voltage divider circuit 22 . If this is a normal cycle, i.e. there is no extra pulse, the transistors T 5 -T 8 will be off and the voltage at the voltage divider circuit 22 at the input to comparator 26 will be the normal amount (for example, sufficient to provide 20 amps to the coils 12 ).
During some conditions, such as cold weather start-up, the microcontroller 16 selectively activates one or more of outputs PK 1 -PK 4 , which will ultimately turn on certain combinations of the transistors T 1 -T 8 . For example, by activating lines PK 1 and PK 2 , transistors T 1 , T 5 , T 2 and T 6 will be switched on during the one-shot 18 pulse. This will place resistors R 1 and R 2 in parallel with resistor RA of voltage divider circuit 20 , raising the voltage input to the comparator 24 . Simultaneously, this will put resistors R 5 and R 6 in parallel with resistor R A in voltage divider circuit 22 , raising the voltage input to the comparator 26 to the same level. As will be understood, by selecting different combinations of PK 1 -PK 4 , sixteen combinations are possible. If the values of resistors R 1 -R 4 are different (and corresponding resistors R 5 -R 8 are equal to resistors R 1 -R 4 ), sixteen different voltage levels can be provided at the inputs to comparators 24 , 26 .
When the pulse from the one-shot 18 is done, all of the NOR gates N 1 -N 4 (whichever combination of PK 1 -PK 4 was active) ensure that all of the transistors T 1 -T 8 are off, thus returning the voltages at the inputs to the comparators 24 , 26 to their normal levels. The comparators 24 , 26 then let the open coils 12 decay below their normal levels before recharging them up to their normal levels again. Note that there would likely be some hysteresis in the driver circuits.
If a longer pulse is desired, the microcontroller 16 can activate the peak delay (PKDLY) line, switching on transistor T D to retrigger the one-shot 18 and restart the timing circuit inside the one-shot 18 .
FIG. 2 is a schematic of a circuit 30 for detecting bad coils 12 , 14 ( FIG. 1 ). First, the bad close coil detection circuitry is as is known in the art. The forward pulse close coil signal, which indicates the beginning of a charging cycle, comes from the controller 16 ( FIG. 1 ) and initiates a one-shot 36 . The output of the one-shot 36 is connected to an input of a NOR gate N 6 . A close coil 20 amp sensor 38 (or whatever the normal fully-charged level of the close coils 14 is) sends a signal to the NOR gate N 6 when the close coils 14 reach full charge. If the close coil current level does not reach the normal full level before the one-shot 36 is done, the NOR gate N 6 goes high. If either (or both) of the inputs to the NOR gate N 7 are high, a fault is indicated at the output of the NOR gate N 7 .
The bad open coil detection circuitry accommodates the pulse that is added at the beginning of the charging cycle. More specifically, the RC circuit inside the one-shot 32 is selectively modified by selectively removing a resistor R 9 from the RC circuit with a transistor T 9 . The transistor T 9 is switched off while the one-shot 18 ( FIG. 1 ) is active by the PEAK signal from the one-shot 18 output ( FIG. 1 ). This puts the additional resistor R 9 in the RC circuit, thereby decreasing the time of the one-shot 32 . Note that the coils 12 are expected to charge to 20 amps (or whatever the normal charging level is) faster when the pulse is added to the beginning of the charging cycle. In the example shown it was determined to be unnecessary to offer sixteen levels of RC timing in the one-shot 32 . Instead, a single adjustment of the RC timing circuit is applied any time there is a pulse of any size. Alternatively, various resistor combinations could be added to the RC circuit similar to the way resistor combinations are added to the voltage dividers in FIG. 1 .
Although a preferred embodiment has been disclosed, a worker of ordinary skill in this art would recognize that certain modifications would come within the scope of the claims. For that reason, the following claims should be studied to determine their true scope and content. | A charging circuit for a fuel injection coil enables the controller to selectively add a pulse of increased amplitude to the beginning of an injection current pulse. Optionally, the controller can also select one of a plurality of amplitudes for the pulse and control the duration of the pulse. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
The present application is a Continuation of International Application No. PCT/EP2005/005969, filed Jun. 3, 2005, and which designates the U.S. The disclosure of the referenced application is incorporated herein by reference.
FIELD OF THE INVENTION
The invention relates to a method for manufacturing a crimped compound thread, and an apparatus for carrying out said method.
BACKGROUND OF THE INVENTION
In a method of manufacturing a crimped compound thread in a single-stage process, first a plurality of synthetic individual threads are produced by extruding a plurality of filament strands, cooling these, and drawing (stretching) them. The individual threads have different characteristics, in particular they may have different colors, so that the coloration of the compound thread depends on the combination of the individual threads. For different applications, the requirements for the appearance (particularly coloration) of the compound thread will differ. It may be particularly desirable to have a compound thread appearance wherein the separate threads do not dominate, but wherein there is not complete mixture of the threads. The dominance of a given color component in the compound thread, if too long (comprising a long segment of the compound thread in which one color dominates), may lead to so-called “flames”. However, often such “flames” are in fact desirable.
EP 0485871A1 discloses a method and apparatus for manufacturing a multicolored compound thread, which method and apparatus have proven to be particularly useful for producing so-called “tricolor threads” for use in carpets. Here a compound thread is produced from multifilament individual threads by common crimping. To achieve such crimping, the individual threads are introduced together into a crimping chamber with the aid of an advancing nozzle. In the crimping chamber, the filaments of the individual threads are laid down into bends and loops, wherewith a common thread plug is formed. Along with the crimping, a certain intermingling of the filaments of the individual threads occurs.
To promote a certain color separation in the compound thread, each of the individual threads is separately subjected to whirl-tangling prior to the crimping, so that the interlacing of filaments in a given thread provides thread cohesion of the component thread. In this way, the intermingling of the individual threads in the compound thread can be improved with regard to color separation. In practice it is desirable to have the color characteristics of the compound thread controllable such that it is possible to manufacture a compound thread with a mixed color wherein the individual threads are intensively intermingled, or to manufacture a compound thread with strong color separation properties wherein the individual threads are not intensively intermingled.
EP 0874072 A1 discloses a method and apparatus wherein the individual threads are separately subjected to whirl-tangling and are separately crimped, prior to combining them to form the compound thread. A basic drawback of this method is that the separation in the compound thread is too pronounced, which is undesirable if one seeks to avoid the appearance of so-called “flames” in a carpet. A further drawback is that the individual threads must be separately crimped, substantially increasing equipment costs, and complicating the process (rendering it more subject to problems) in the case of a multi-thread apparatus.
DE 4202896 A1 discloses another method and apparatus, wherein the individual threads are given a “false twist” before being fed into the crimping device. This creates a risk that certain individual threads will be too dominant in the compound thread, and further that the crimping (texturizing) effect in the individual threads will be hindered.
An underlying problem of the present invention was to devise a refined method and apparatus of the type described initially supra, which enable maximum flexibility to attain particular color effects in the compound thread, in the range from mixed colors to highly separated colors.
A second underlying problem was to enable reproducible adjustability of the color appearance of the compound thread.
SUMMARY OF THE INVENTION
These problems are solved according to the invention by a method described herein, and an apparatus described herein.
Advantageous refinements of the invention are set forth in the features and combinations of features of the various embodiments described herein.
The invention is based on the concept that one can achieve very wide-ranging effects with the appropriate application of whirl-tangling of multifilament threads. E.g., by whirl-tangling a multifilament thread one can achieve intermingling or snarling of the filaments of the thread. This determines the intensity of the thread cohesion, depending on the stage of treatment of the thread. According to the invention, at least one of the multifilament threads is subjected to multiple whirl-tanglings. In particular, at least one of the multifilament individual threads is subjected to whirl-tangling a plurality of times, in a plurality of pre-treatment stages, to provide a desired filament cohesion, prior to the crimping of the individual threads. Another advantage of the invention is that the common texturizing of the individual threads can be retained in the compound thread. The multiple whirl-tangling of the individual threads enables the coloration of the compound thread to be varied within wide limits not attainable by other methods. Thus, if one seeks a high degree of color separation one will subject each of the individual threads to whirl-tangling in a number of pre-treatment stages. If one seeks the appearance of mixed coloration in the compound thread, one will preferably subject only one of the multifilament individual threads to whirl-tangling (in a plurality of pre-treatment stages).
The variant method according to which each of the multifilament individual threads is separately subjected to whirl-tangling in a first pre-treatment stage prior to drawing is distinguished in that the individual threads can be passed through the drawing device very smoothly, and disposed very close together. In this connection, the whirl-tangling of the individual threads in the first pretreatment stage can be adjusted to achieve an optimum degree of filament cohesion for the drawing of the individual threads.
In order to achieve special effects in the nature of mixing or separation of colors in the compound thread, according to a preferred variant of the method at least one of the individual threads is, or all of said threads are, subjected separately to whirl-tangling in a second pre-treatment stage following the stretching. In this way, the filament cohesion brought about via the whirl-tangling of the individual threads can be adjusted specifically for the subsequent common crimping of the individual threads.
The adjustability and range of variability of the coloration of may be improved if, in at least one of the pre-treatment stages, whirl-tangling is carried out on the individual threads, wherewith the set-point values of the compressed air in the compressed air feed are at respective different values for the different threads. In this way, one can provide different degrees of whirl-tangling in different parallel advanced individual threads. E.g. if it is desired to produce a compound thread wherein in addition to a dominant individual thread a second component is present which contributes a mixing color, the individual thread having the color-determining contribution may be subjected to whirl-tangling with a relatively high set-point value of the compressed air. It turns out that this value is proportional to the points of intermingling (“intermingling knots”) in the thread.
It is also possible to carry out whirl-tangling of the individual threads in the pre-treatment stages wherewith the set-point values of the compressed air in the compressed air feed are at respective different values for different such stages. Thus, e.g. for the drawing process the thread should have a relatively low filament cohesion, in order not to inhibit the stretching of the individual filaments. In contrast, for the common crimping of the individual threads it is desirable for the whirl-tangling to be adjusted for the desired color characteristics.
Also, it is possible to carry out whirl-tangling with pulsation of the pressure, e.g. in the second pre-treatment stage, in order to vary the mixing of the colors. This also enables the creation of special yarn effects for manufacture of “fancy yarns”.
In order to intensify the whirl-tangling treatment prior to the crimping of the individual threads, it has been found advantageous to employ a variant method according to which the multifilament individual threads are subjected to whirl-tangling with the aid of heated compressed air. Alternatively, the individual threads may be heated prior to the whirl-tangling. This has been found to exert influence on the intermingling of the filaments in the individual threads, and on the crimping of the compound thread.
In order to provide appreciable tension in the threads at the point of the crimping of the individual threads, independently of the tension in the threads in the course of the preceding stage(s) of whirl-tangling, according to a variant method it is advantageous if, prior to the crimping, the individual threads are passed multiple times around a galette unit, and are subjected to whirl-tangling in a thread segment of the resulting loops in said galette unit, prior to leaving the galette unit.
If one employs heated galettes, one may advantageously accomplish temperature-controlled simultaneous whirl-tangling of the individual threads.
In order to achieve the thread cohesion necessary for final processing of the compound thread, the compound thread is subjected to tangling after the crimping of the individual threads and prior to the winding onto a bobbin, wherewith the coloration of the compound thread which has been imparted in the pre-treatment stages and via the crimping of the individual threads is substantially preserved.
The inventive method is particularly well suited to the manufacture of a compound thread comprised of a plurality of component threads each of which preferably is different. However, the scope of the invention is not limited to situations with component threads having different characteristics, in light of the fact that, in particular, individual pre-treatment of identical individual threads can advantageously be employed to produce a compound thread. E.g., the individual threads may be given specific structural properties in the course of pretreatment by whirl-tangling in two different stages.
In another advantageous variant of the inventive method, the individual threads undergo separate whirl-tangling in a first stage of pre-treatment and then all of them undergo a common whirl-tangling in a second stage of pre-treatment. The multi-stage whirl-tangling prior to the texturizing according to the invention provides a very high degree of flexibility in the pre-treatment of the individual threads prior to said texturizing. Thus it is also possible to subject the individual threads to a common whirl-tangling in the first pre-treatment stage and to separate whirl-tangling in the second pre-treatment stage.
Further, the scope of the inventive method is not limited to situations with common crimping of the individual threads. It is basically also possible to separately texturize each of the individual threads, prior to combining them. In another possible method, texturizing of the individual threads (commonly or separately) and combining of the individual threads to form a compound thread are carried out, following which, after cooling, the compound thread is separated again into component threads, and then said threads are subjected to common whirl-tangling prior to winding as the final compound thread. Such a variant method may be employed with individual threads of different colorations, in order to achieve additional coloration effects.
The apparatus for carrying out the inventive method is comprised of a whirl-tangling device comprised of a plurality of whirl-tangling units which are disposed in succession in the path of advance of the individual threads.
In order to be able to carry out processing steps on the individual threads between the individual whirl-tangling steps, advantageously a first whirl-tangling unit is disposed upstream of the drawing device, wherewith said first whirl-tangling unit has a respective whirl-tangling nozzle for each of the individual threads.
Advantageously a second whirl-tangling unit having a plurality of whirl-tangling nozzles is disposed between the drawing device and the crimping device.
In order to be able to carry out the whirl-tangling of the individual threads in the individual pre-treatment stages with different set-point values of the compressed air pressure, each of the whirl-tangling nozzles has a controllable compressed air supply. In this connection, a plurality of whirl-tangling nozzles may simultaneously have a common compressed air supply, or one or more whirl-tangling nozzles may have separate compressed air supplies.
In order to obtain special effects which previously were obtained by thermal whirl-tangling, the inventive apparatus may be expanded to comprise heating means associated with at least one of the whirl-tangling units, whereby certain compressed air is heated.
Alternatively, a heating device may be provided upstream of the whirl-tangling unit, for heating the individual threads.
To achieve independent adjustment of thread tension in the whirl-tangling of the individual threads and in the crimping process, preferably in the inventive apparatus the drawing device is comprised of a galette unit disposed upstream of the crimping device, wherewith the individual threads are guided over said galette unit in multiple loops; and the whirl-tangling nozzles of a second whirl-tangling unit are arranged such that the individual threads can be subjected to whirl-tangling prior to leaving the galette unit.
If the whirl-tangling nozzles of the second whirl-tangling unit are disposed in a segment looped around galettes, which segment is between two galettes, namely in the last loop, the tension of the thread(s) in the whirl-tangling process can be reduced to a desired value if the individual threads at the point of leaving the galette unit are passed over a reduced diameter step in the galette. Basically any of the segments between the two galettes is acceptable as a location for disposing the whirl-tangling nozzles for carrying out whirl-tangling in the second pre-treatment stage.
In order to achieve additional thermal effects in the whirl-tangling of the filaments, according to an advantageous refinement of the invention the galette unit is comprised of at least two driven galettes, wherewith at least one of the galettes is configured so as to be heatable.
For final establishment of the thread cohesion in the compound thread, a tangling device is disposed between the crimping device and a winding device which is provided for winding the compound thread onto a bobbin or the like.
To provide intensive and uniform crimping of the individual threads, a variant apparatus been found to be particularly advantageous in which the crimping device comprises an advancing nozzle and an associated crimping chamber, wherewith the individual threads are advanced as a group into the crimping chamber by means of the advancing nozzle, wherewith a thread plug is formed.
BRIEF DESCRIPTION OF THE DRAWINGS
The inventive method will be described in more detail hereinbelow with the aid of an exemplary embodiment of the inventive apparatus, with reference to the accompanying drawings.
FIG. 1 is a schematic drawing of a first exemplary embodiment of the inventive apparatus for carrying out the inventive method;
FIG. 2 is a schematic drawing of a second exemplary embodiment of the inventive apparatus;
FIG. 3 is a schematic drawing of a variant of the exemplary embodiment of FIG. 1 ;
FIG. 4 is a schematic drawing of a variant of the exemplary embodiment of FIG. 2 ;
FIG. 5 is a schematic drawing of a variant of the exemplary embodiments of FIGS. 1 and 2 ; and
FIG. 6 is a schematic drawing of an exemplary embodiment of a separating thread guide.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
FIG. 1 shows schematically an exemplary embodiment of an inventive apparatus for carrying out the inventive method. The apparatus has a spinning device 1 which is connected to one or more melters (not shown). The spinning device has a heated spinning frame 2 which bears a plurality of spinnerets (“spinning nozzles”) ( 3 . 1 - 3 . 3 ) arrayed side by side. Each spinneret ( 3 . 1 - 3 . 3 ) has on its underside a plurality of orifices through which the polymer melt stream fed to said nozzle is extruded under pressure to form a respective individual filament. A cooling device 4 is disposed below the spinning device 1 ; the extruded filaments, which leave the spinning device at a temperature close to their melting temperature, are guided through the cooling device in order to cool said filaments. The cooling device 4 may comprise, e.g., a blower which blows cooling air essentially transversely against the filaments. After the filaments are cooled, the filament strands ( 13 . 1 - 13 . 3 ) associated with the respective spinnerets ( 3 . 1 - 3 . 3 ) are combined, at the exit of the cooling device 4 , to form respective individual threads ( 6 . 1 - 6 . 3 ).
At the outlet of the cooling device 4 , a “preparation device” 7 is provided, along with respective thread guides ( 5 . 1 - 5 . 3 ) for each of the individual threads ( 6 . 1 - 6 . 3 ).
To draw out the individual threads ( 6 . 1 - 6 . 3 ) from the spinnerets ( 3 . 1 - 3 . 3 ), a drawing device 10 is provided which comprises at least one galette device 18 (dashed lines) which is configured for drawing-out. The individual threads ( 6 . 1 - 6 . 3 ) are guided in parallel paths through the drawing device 10 . In this, the individual threads can be drawn in a common arrangement, or individual delivery devices may be employed (one for each thread).
After the drawing-out and stretching of the individual threads ( 6 . 1 - 6 . 3 ) by the drawing device 10 , the individual threads ( 6 . 1 - 6 . 3 ) are brought together in a crimping device 11 and combined to form a compound fiber 21 .
In this exemplary embodiment, the crimping device 11 is comprised of an advancing nozzle 15 and a crimping chamber 16 which cooperates with the nozzle 15 . The advancing nozzle 15 is connected to a pressure source (not shown) by means of which a conveying medium is fed to the advancing nozzle 15 . The conveying medium causes the individual threads ( 6 . 1 - 6 . 3 ) to be drawn into the advancing nozzle 15 and then advanced into the crimping chamber 16 where they are formed into a “fiber plug”. This involves a partial intermingling of the individual threads ( 6 . 1 - 6 . 3 ). The thread plug 22 , which preferably is formed by means of a hot conveying medium, is then passed to a cooling drum 17 and cooled.
For pre-treatment of the individual threads ( 6 . 1 - 6 . 3 ), a first whirl-tangling unit 8 . 1 is provided between the preparation device 7 and the drawing device 10 ; and a second whirl-tangling unit 8 . 2 is provided between the drawing device 10 and the crimping device 11 . The first whirl-tangling unit 8 . 1 has a plurality of whirl-tangling nozzles ( 9 . 1 - 9 . 3 ), each associated with a respective individual thread ( 6 . 1 - 6 . 3 ). Each whirl-tangling nozzle ( 9 . 1 - 9 . 3 ) has a thread channel through which the individual thread is guided. A pressure channel opens out laterally into the thread channel, to introduce a high energy compressed fluid, preferably compressed air, into the thread channel. The pressure channels are connected to a pressure source via a compressed air supply line 12 . 1 and pressure adjusting means 14 . 1 . A control device 24 is provided, which is connected to the pressure adjusting means 14 . 1 , for setting the set-point for control of the compressed air.
The structure and configuration of the whirl-tangling nozzles ( 9 . 1 - 9 . 3 ) is generally known, and is described in, e.g., DE 10 2004 007073 A1.
The second whirl-tangling unit 8 . 2 associated with the crimping device 11 also has a plurality of whirl-tangling nozzles ( 9 . 4 - 9 . 6 ), having a structure and configuration essentially identical to the structure and configuration of the whirl-tangling nozzles ( 9 . 1 - 9 . 3 ) of the first whirl-tangling unit 8 . 1 . The whirl-tangling nozzles ( 9 . 4 - 9 . 6 ) are connected to a pressure source (not shown) via a compressed air supply line 12 . 2 and pressure adjusting means 14 . 2 . The pressure adjusting means 14 . 2 are connected to the control device 24 , for setting and varying the set-point for control of the compressed air. This allows the whirl-tangling units ( 8 . 1 , 8 . 2 ) to be operated mutually independently in carrying out whirl-tangling of the threads ( 6 . 1 - 6 . 3 ).
For post-treatment of the crimped compound thread 21 produced from the individual threads ( 6 . 1 - 6 . 3 ), the crimping device 11 has disposed downstream of it a “tangling device” 19 , inside which the compound thread 21 receives a final treatment required for the further processing.
Following this “tangling”, the compound thread 21 is taken up on a winding device 20 wherewith it is wound on a bobbin or the like 23 .
In the process, the winding device 20 serves simultaneously as a drawing organ, to draw the crimped compound thread 21 from the thread plug 22 . In order to be able to adjust the tension in the compound thread 21 in the winding and in the “tangling”, said thread may be drawn from the thread plug 22 by means of a galette device; and a second galette unit may be provided downstream of the “tangling device” 19 , as the thread is passed to the winding device 20 . The configurations of the devices in the post-treatment zone do not bear upon the invention—any suitable processing means and treatment stages may be chosen for influencing the compound thread 21 prior to winding onto the bobbin 23 .
In the exemplary embodiment of the inventive apparatus illustrated in FIG. 1 , three bundles of filaments ( 13 . 1 - 13 . 3 ) disposed side by side are spun in the spinnerets ( 3 . 1 - 3 . 3 ); each of these bundles has a plurality of filament strands. The filament bundles ( 13 . 1 - 13 . 3 ) may have different properties; preferably the basic polymers of which they are comprised have different colors. Indeed, the basic polymers may have different compositions or may contain different amounts of additives.
Each of the filament bundles ( 13 . 1 - 13 . 3 ) is combined to form an individual thread ( 6 . 1 - 6 . 3 ). For this purpose, the filament bundles ( 13 . 1 - 13 . 3 ) are subjected to addition of preparation agents by means of the preparation device 7 , and are passed through the thread guides ( 5 . 1 - 5 . 3 ), from which the individual threads emerge.
For further treatment of the individual threads ( 6 . 1 - 6 . 3 ), in a first pre-treatment stage immediately following the “preparation” a first whirl-tangling is carried out, in whirl-tangling unit 8 . 1 . For this, each individual thread ( 6 . 1 - 6 . 3 ) is passed through a whirl-tangling nozzle ( 9 . 1 - 9 . 3 ). The whirl-tangling unit 8 . 1 has a pressure set-point value for the compressed air which is supplied, which leads to intermingling (interlacing) of the filaments of which the individual threads are comprised. In this process, one achieves uniformization of the preparation, as well as the minimum filament cohesion required for the subsequent drawing by the galette in the drawing device 10 . In the setting of the pressure set-point value, one should take care to avoid excessive snarling of the filaments of the individual threads.
After the individual threads ( 6 . 1 - 6 . 3 ) have been drawn out and stretched, a second whirl-tangling of said threads is carried out via the whirl-tangling unit 8 . 2 , in the second pre-treatment stage. In this unit 8 . 2 , the individual threads ( 6 . 1 - 6 . 3 ) are individually separately guided and whirled, by means of the whirl-tangling nozzles ( 9 . 4 - 9 . 6 ). In this process, the intermingling of the filaments in the individual threads ( 6 . 1 - 6 . 3 ) which is brought about is chosen such that a certain intermingling is achieved in the crimping of the individual threads ( 6 . 1 - 6 . 3 ) which are combined into the compound thread 21 . In particular, in producing a multicolored crimped compound thread the coloration of the compound thread 21 can be influenced within wide bounds. Thus, e.g., a compound thread with strong color separation can be produced by setting the set-point value of the pressure of the compressed air supply in the second whirl-tangling unit 8 . 2 relatively high. This causes intensive intermingling of the filaments of the individual threads, wherewith the subsequent crimping process will not be able to substantially undo this intermingling. If the set-point value of the pressure in the whirl-tangling unit 8 . 2 is set relatively low, the compound thread 21 will have an appreciably mixed coloration.
After the whirl-tangling in the second pre-treatment stage, the individual threads ( 6 . 1 - 6 . 3 ) are jointly crimped and are combined to form the compound thread 21 . In this process, the individual threads ( 6 . 1 - 6 . 3 ) are advanced through the advancing nozzle 15 by means of an advancing fluid, into an adjoining crimping chamber 16 . In the crimping chamber 16 , the filaments of the individual threads ( 6 . 1 - 6 . 3 ) are laid down into bends and loops in the course of formation of a thread plug 22 , which is subjected to thermal treatment and is then opened to yield the crimped compound thread 21 . To produce the final thread characteristics (thread cohesion, body, strength, etc.), the compound thread 21 undergoes “tangling” in the tangling device 19 prior to being wound on the bobbin 23 .
The inventive method and apparatus may be employed to produce, e.g., multicolored crimped compound threads which have high color uniformity. If necessary or desirable, particular visual characteristics can be imparted by adjusting the pre-treatment.
FIG. 2 illustrates a second exemplary embodiment of an inventive apparatus for carrying out the inventive method. This embodiment is substantially the same as the above-described embodiment; accordingly, reference is made here to the description of that embodiment, and the emphasis hereinbelow will be on describing the differences. Components with identical functions have been assigned like reference numerals.
In the exemplary embodiment according to FIG. 2 , the drawing device 10 may be comprised of, e.g., two galette units ( 18 , 27 ) for drawing out, each of which is comprised of two driven galettes or a driven galette with an “overflow roll”, wherewith the individual threads ( 6 . 1 - 6 . 3 ) are guided in parallel paths over the galettes. The galette units ( 18 , 27 ) are driven at different speeds, causing stretching of the threads ( 6 . 1 - 6 . 3 ).
In order to provide a second pre-treatment stage wherein the individual threads ( 6 . 1 - 6 . 3 ) are prepared for the crimping, a second whirl-tangling unit 8 . 2 is provided between the drawing device 10 and the crimping device 11 . The whirl-tangling unit 8 . 2 has a plurality of whirl-tangling nozzles ( 9 . 4 - 9 . 6 ), each of which is associated with a respective individual thread. These nozzles ( 9 . 4 - 9 . 6 ) are mutually independently controllable. Each of the whirl-tangling nozzles ( 9 . 4 - 9 . 6 ) has a respective compressed air feed ( 12 . 3 - 12 . 5 ) with respective pressure adjusting means ( 14 . 3 - 14 . 5 ), each of which pressure adjusting means is connected to the control device 24 , which enables providing a set-point value for the pressure for each of the whirl-tangling nozzles ( 9 . 4 - 9 . 6 ). It should be noted that the pressure adjusting means ( 14 . 3 - 14 . 5 ) are devised such that they can completely shut off the compressed air feed. This provides a high degree of flexibility in the pre-treatment of the individual threads ( 6 . 1 - 6 . 3 ) immediately upstream of the crimping stage.
Thus it is seen that the exemplary embodiment for carrying out the inventive method as illustrated in the FIG. 2 has somewhat higher flexibility to attain particular effects in a compound thread comprised of the differently whirl-tangled individual threads ( 6 . 1 - 6 . 3 ). Thus, e.g., is it possible to produce a multicolored compound thread the appearance of which results from a strongly separated pair or trio of colors, resulting from, e.g. the use of three differently colored individual threads ( 6 . 1 - 6 . 3 ) wherewith one of the threads is subjected to whirl-tangling in the second pre-treatment stage and the other threads do not receive any additional whirl-tangling in said second pre-treatment stage.
The exemplary embodiments of the inventive apparatus illustrated in FIGS. 1 and 3 can be varied by additional means, agents, and combinations, in order to, e.g., achieve special effects in the pre-treatment prior to the crimping of the individual threads. E.g., FIG. 3 shows a variant of the exemplary embodiment according to FIG. 1 ; in FIG. 3 only the drawing device 10 , whirl-tangling unit 8 . 2 , and crimping device 11 are illustrated (again, schematically). Since the components which are not illustrated are essentially identical to the corresponding components in FIG. 1 , reference is made to here the preceding descriptions, and only the differences will be described hereinbelow.
For each of the threads ( 6 . 1 - 6 . 3 ), the whirl-tangling unit 8 . 2 has a respective whirl-tangling nozzle ( 9 . 4 - 9 . 6 ), connected to a pressure source via the compressed air supply line 12 . 2 and pressure adjusting means 14 . 2 . The compressed air supply line 12 . 2 additionally has heating means 26 , for preheating the fluid introduced via the whirl-tangling nozzles ( 9 . 4 - 9 . 6 ). The heating means 26 and pressure adjusting means 14 . 2 are connected to a control device 24 .
In the exemplary embodiment illustrated in FIG. 3 the whirl-tangling of the individual threads ( 6 . 1 - 6 . 3 ) in the second pre-treating stage is accomplished with a heated fluid, which causes heating of the filaments of the individual threads. This heating influences the intermingling of the said individual filaments and leads to intensified crimping. This early intermingling substantially survives the subsequent processing.
FIG. 4 is a detail view of a variant embodiment of the inventive apparatus according to FIG. 2 . The structure and configuration of the process aggregate not shown is generally the same as in the preceding exemplary embodiment, and therefore does not require further description here. The drawing device 10 , whirl-tangling unit 8 . 2 , and crimping device 11 are included in the detail view shown in FIG. 4 . The drawing device 10 is comprised of a first galette unit 18 configured for drawing and a second galette unit 27 configured for drawing, each of which has two galettes ( 28 . 1 , 28 . 2 ) around which the individual threads ( 6 . 1 - 6 . 3 ) are passed multiple times. The galettes ( 28 . 1 , 28 . 2 ) of the galette unit 27 are heated, so that the individual threads ( 6 . 1 - 6 . 3 ) on the periphery of the galettes ( 28 . 1 , 28 . 2 ) undergo heating. The whirl-tangling unit 8 . 2 is disposed between the heated galettes ( 28 . 1 , 28 . 2 ). This whirl-tangling unit 8 . 2 is identical to that of the exemplary embodiment illustrated in FIG. 2 ; each individual thread ( 6 . 1 - 6 . 3 ) is acted on by (“has associated with it”) a respective whirl-tangling nozzle. The whirl-tangling unit 8 . 2 here is disposed in a segment of the threads between the galettes 28 . 1 and 28 . 2 . E.g., the whirl-tangling unit 8 . 2 may be disposed in the last such segment of the individual threads ( 6 . 1 - 6 . 3 ).
After the individual threads ( 6 . 1 - 6 . 3 ) leave the heated galette, they are sent together to the crimping device 11 where they are compressed to form a thread plug 22 .
In a variant of the inventive apparatus according to FIG. 4 , the whirl-tangling of the heated individual threads can be carried out with the individual thread(s) being heated, and the tensioning of the individual threads as part of the texturizing of said threads in the crimping device 11 can be chosen to be independent of the tensioning of the individual threads in the whirl-tangling in the second pre-treating stage. Thus, e.g., a diameter step may be provided on the heated galette 28 . 1 to enable setting different tensioning values for the whirl-tangling. The diameter step 33 of the galette 28 . 1 in the last segment of the individual threads is shown as a dotted line in FIG. 4 , and is implemented immediately downstream of the whirl-tangling unit 8 . 2 . Another advantage of the variant illustrated in FIG. 4 is that the individual threads have a defined point of leaving from the galettes 28 . 1 . The individual threads pass from the last galettes to the crimping device in a very smooth manner.
The arrangement illustrated in FIG. 4 may advantageously have galettes which are un-heated, wherewith the whirl-tangling is carried out at ambient temperature.
FIG. 5 illustrates yet another exemplary embodiment of a variant method and apparatus applicable to the system according to FIGS. 1 and 2 .
In the variant embodiment illustrated in FIG. 5 , there are disposed between the cooling drum 17 and the winding device 20 a first drawing galette device 29 . 1 , a separating thread guide 30 , a “tangling device” 19 , and a second drawing galette device 29 . 2 . The components disposed upstream of the cooling drum 17 may be as in the exemplary embodiment according to FIG. 1 or 2 , to which reference is made here.
In the variant embodiment illustrated in FIG. 5 , the compound thread 21 , after crimping and after cooling on the periphery of the cooling drum 17 , is drawn off via the first galette device 29 . 1 . The galette device 29 . 1 is shown here as a driven galette with an associated coordinated roll. For post-treatment, the compound thread 21 is separated into individual threads ( 6 . 1 - 6 . 3 ), by passing the individual threads through a separating thread guide 30 before they enter the tangling device 19 . In the tangling device 19 , the separately advancing individual threads ( 6 . 1 - 6 . 3 ) are once again subjected to whirl-tangling, and re-combined into a compound thread 21 . The compound thread 21 is drawn off via the drawing galette 29 . 2 and is passed on to the winding device 20 , where it is wound onto the bobbin 23 . The separation of the compound thread prior to post-treatment allows production of additional special visual effects. In this connection it is possible that, prior to the post-treatment, at least one of the individual threads is subjected to additional treatment in the form of whirl-tangling, after said separation.
In the variant embodiment illustrated in FIG. 5 , the compound thread 21 is separated into the individual threads ( 6 . 1 - 6 . 3 ). In this, preferably a separating thread guide 30 is employed which preferably is configured according to the exemplary embodiment illustrated in FIG. 6 . The separating thread guide 30 has a disc-shaped support member 32 which is fixed laterally to a machine frame. The support member 32 has a plurality of guiding eyes ( 31 . 1 - 31 . 3 ) on its periphery which are disposed at mutual distances apart. In the embodiment illustrated in FIG. 6 , these eyes ( 31 . 1 - 31 . 3 ) are disposed at the apices of an equilateral triangle. Preferably each such eye has a ceramic insert, which enables the individual threads ( 6 . 1 - 6 . 3 ) to be separately fed to the tangling device 19 , in this embodiment.
The described exemplary embodiments for carrying out the inventive method are in the nature of examples, in their arrangements and in the choice of processing devices. Thus, additional pre-treatment and post-treatment stages and means may be introduced, e.g. for the purpose of subjecting the individual threads to additional treatments prior to texturizing, or subjecting the compound thread to additional treatments after the texturizing, etc. Likewise the characteristics and form of the crimping device are in the nature of examples. To realize particular crimping characteristics, the individual threads may be texturized using different parameters. Separately performed crimping also enables the use of different crimping methods, wherewith the crimped individual threads will then be combined into a compound thread. The number of individual threads illustrated in the exemplary embodiments is, of course, in the nature of an example. A compound thread may be formed from two or more individual threads. | The invention relates to a method and a device for producing a crimped composite thread, wherein the inventive method consists in extruding, cooling and in drawing several yarns in the form of a plurality of strand filaments and in jointly crimping them in order to obtain a crimped composite thread. The aim of said invention is to make it possible to pre-treat the threads in a manner adaptable to each treatment step. The aim is attained by that at least one multi-treaded yarn is whirl-tangled many times during several operations prior to crimping. For this purpose, a whirl-tangling device provided with a plurality of whirl-tangling units following each other in a direction of the yarn displacement is used. | 3 |
BACKGROUND OF THE INVENTION
This invention relates to an ashtray device built into a panel, for example, into the dashboard of an automobile.
The ashtray devices installed near the driver's seat in cars have been improved in various minor ways, but the basic design that requires the ashtray to be manually pulled out at the time of use still persists. For drivers, the act of pulling out an ashtray while driving is fairly dangerous. While pulling out the ashtray, the driver is, of course, required to retain a hold on the steering wheel. More often than not, the driver keeps his burning cigarette between the fingers of the hand being used to pull out the ashtray. Not infrequently, ashes fall off the burning cigarette onto the floor as when the burning end of the cigarette is inadvertently hit against the front plate of the ashtray before the ashtray is pulled out. If a part of the burning portion at the tip of the cigarette happens to fall together with ashes, the floor carpet of the car may start to burn. The driver therefore has to look to see where the ashes have fallen and in doing so he takes his eyes off the road.
While the interiors of automobiles are increasingly luxurious, the ashtrays alone have remained little changed. From the standpoint of design and function, the conventional drawer type ashtrays have poor commercial value.
SUMMARY OF THE INVENTION
An object of this invention is to provide an ashtray device built into a panel which is brought into position for use by application of an instantaneous pressure to the ashtray.
To accomplish the object described above according to the present invention, there is provided an ashtray device so constructed that the ashtray unit thereof is stowed in a housing behind the panel where it is kept energized in its opening direction and, upon application of an external pressure thereto, the ashtray unit is thrust out of the panel and brought to its service position.
Since the ashtray unit of the device of this invention is readily brought into its service position by one touch of the driver's finger as described above, the driver is relieved of the special care heretofore required in the use of the conventional ashtray and is allowed to devote all his attention to the operation of his automobile even during the use of the ashtray unit.
The other objects and characteristics of the present invention will become apparent from the further disclosure of the invention to be made herein with reference to the accompanying drawings.
BRIEF EXPLANATION OF THE DRAWINGS
FIG. 1 is a partially cutaway exploded perspective view of the first embodiment of the ashtray device according to this invention.
FIG. 2 is a perspective view illustrating the relation between the base plate unit and the link in the ashtray device of FIG. 1.
FIG. 3 is a lateral cross section of the ashtray device of FIG. 1.
FIG. 4 is a sectioned view taken along the line IV--IV in FIG. 3.
FIG. 5(A) is an explanatory diagram illustrating the condition which is assumed when the link in the ashtray device of FIG. 1 is not operated.
FIG. 5(B) is an explanatory diagram illustrating the condition which is assumed when the link is operated.
FIG. 6 is a partially cutaway front view illustrating the ashtray unit of the second embodiment of the ashtray device of the present invention.
FIG. 7 is a front view illustrating the housing of the second embodiment.
FIG. 8 is a cross sectional side view illustrating the ashtray device having the ashtray unit of FIG. 6 accommodated in the housing of FIG. 7.
FIG. 9(A) is a side view illustrating the state of movement of the arm in the movement of the ashtray unit of the second embodiment from the closed posture to the open posture.
FIG. 9(B) is a front view showing the arm of FIG. 9(A).
FIG. 9(C) is a side view illustrating the state of movement of the arm in the movement of the ashtray unit of the second embodiment from the open posture to the closed posture.
FIG. 10 is a left side view illustrating the ashtray device of the second embodiment.
DESCRIPTION OF PREFERRED EMBODIMENTS
FIGS. 1 to 5 illustrate one embodiment of the ashtray device according to the present invention, which comprises three principal units. The first unit is an ashtray 1. Like any of the ashtrays in general use, the ashtray unit 1 is provided with a tray 2 for holding ashes and cigarette butts (a box-shaped tray in the illustrated embodiment) and a front plate 3 therefor. In this case, the front plate 3 is fairly large, protruding in the shape of a flange from the four sides of the tray 2. The second unit is a housing 4 for accommodating the ashtray unit 1. As described more fully afterward, this housing 4 is desirably adapted to snap into engagement with the panel surface in which the ashtray device is wholly buried. The third unit is an open-shut control mechanism 5 for the ashtray unit 1. This mechanism 5, interlocked with the tray 2, is used for automatically opening the tray 2 and for keeping the tray 2 in a closed state.
These component parts are produced such as by the injection molding of a plastic material, or from other suitable materials such as metals.
The housing 4 is in the shape of a box, having an inner hollow portion 6 with a front opening 6'. From its top plate 7 through its rear wall 8, the housing forms a continuously curved wall 9 conforming to the locus described by the tail ends of the tray and the control mechanism during the rotary ascent of the tray which is described in detail in a later paragraph. The curved wall has its significance in avoiding wasteful use of material. On the inner surface of this rear curved wall 9 are disposed an engaging step portion 10 used for keeping the ashtray unit in the closed state and a stopper step portion 11 used for fixing the largest angle of the opening of the ashtray unit. The angle formed by the straight lines drawn to the step portions 10, 11 from the straight line X connecting the centers of the bearing holes 13 formed in the front lower portions of the side walls 12 of the housing constitutes the largest angle of rotation α allowed for the ashtray unit (FIG. 3).
In the innermost recess of one of the side walls of the housing (FIG. 1), there is disposed a curved rack gear 14 extended inwardly, faced forward, and describing an arc with the bearing hole 13 as the center. The interval between the inner lateral wall 15 of the gear and the other side wall 12 substantially constitutes the width of the space for accommodating the control mechanism 5 and the tray 2.
The open-shut control mechanism 5 possesses a base plate 16 which assumes a position substantially parallel to the inner floor of the housing when the ashtray unit is closed. On this base plate 16 are provided various component parts to be described afterward.
On the opposite lateral ends of the base plate 16 are formed lateral walls 17. At the opposite ends of its front side, there are provided symmetrical shafts 18 extended sidewise.
When these shafts 18 are inserted into the bearing holes 13 of the housing 4, the base plate 16 is rotatably attached to the housing 4. To facilitate this insertion, the front parts of the lateral walls 17 are connected to the rear parts thereof only through the hinge portions 20 formed by inserting vertical slits 19. Moving around these hinge portions 20, the front and rear parts can be brought toward each other as though in a squeezing manner. In other words, the distance between the shafts 18 is contracted by this squeeze to permit the insertion of the base plate 16 into the housing interior 6. The squeeze is released when the shafts 18 are registered with the bearing holes 13. Consequently, the front parts of the lateral walls regain their original positions owing to the resilience of the material of the hinge portions 20 and the shafts find their way into the bearing holes. To avoid obstructing this motion of the front parts of the lateral walls, the front part of the base plate has a thin enough width to maintain a space from the front parts of the lateral walls.
In this embodiment, one of the shafts 18 has a coil spring 21 fitted thereon. One end of the coil spring 21 is set in a small groove 22 of the lateral wall 17 of the base plate and the other end thereof is set in a small groove 24 formed in a frame portion 23 beside the front opening 6' of the housing. In this arrangement, the coil spring 21 is allowed to accumulate energizing force therein when the base plate 16 is brought to a position parallel to the inner floor surface of the housing. As a result, the base plate 16 is always kept energized in the direction of urging its tail end around the axis X.
On the other hand, the base plate is provided with engaging means adapted to keep the base plate substantially in its horizontal state (first posture) by being brought upwardly into engagement with the aforementioned engaging step portion 10 against the energizing force mentioned above and release means adapted to release the engaging means and bring the base plate into a tilted state (second posture) by virtue of the energizing force of the energizing means (coil spring) 21.
In the present embodiment, the engaging means and a push button, serving as the operating member the driver is required to use in releasing the engaging means, are formed on a link 25 obtained in a one-piece form by one-shot molding of a plastic material. This link 25 is operably attached to the rear surface of the base plate 16. Reference to the perspective view of FIG. 2 showing the rear surface of the base plate 16 will facilitate comprehension of the working of the link to be described below.
The push button portion 26 which the driver is required to depress when he wishes to open the ashtray is formed at the leading end of the first link rod 27. At the tail end of the first link rod, the engaging surface 28 with which the link-resetting spring to be described in detail afterward comes into contact is formed in the shape of a step. The rear end portion of the first link rod which departs from this step in a converging state is flexibly connected to the second link rod 30 through the medium of a thin-walled hinge 29.
While the link 25 remains out of service, the first and second link rods 27, 30 are bent at the hinge 29 substantially at right angles relative to each other. The second link rod 30 is provided with a cylindrical portion 32 containing a suitably diverged perforation 31 in the vertical direction.
To the other end of the second link rod 30, a third link rod 34 is connected via a hinge 33. The second and third link rods 30, 34 are similarly connected to each other substantially at right angles when the link is out of service. The third link rod 34 extends in the opposite direction with reference to the first link rod 27. When the link 25 is so positioned that the push button portion 26 at the leading end of the first link rod 27 falls on the front side, an engaging surface 35 with which the engaging step portion 10 and the stopper step portion 11 of the housing selectively come into contact is formed on the upper surface of the rear end of the third link 34.
The attachment of the link 25 to the base plate 16 can easily be effected by keeping the base plate upside down and lowering the link 25 from above and bringing its component parts into engagement with the matched parts of the base plate. To be specific, the first and third link rods 27, 34 are dropped into the space between the pair of hooks 36, 37 which are opposed to each other and raised at matched positions on the rear surface of the base plate. Then, the link rods are advanced past the hooks 36, 37 while the claw-like width-contracted portions of the hooks 36, 37 are both pushed away from each other. Then, the hooks 36, 37 are allowed to regain their original shape by virtue of the resilience of their own material. Consequently, the link rods are secured to the base plate because the claws of the hooks catch firm hold of the lower sides of the link rods. At this point, the vertical perforation 31 in the second link rod 30 slides on a shaft 38 provided on the rear side of the base plate portion, giving rise to the axis Z as the center of rotation for the second link rod 30. Further, to prevent the second link rod 30 from falling off in the downward direction, the base plate portion is provided with a hook 39 adapted to support the lower side of the cylindrical portion 32.
When the hooks 36, 37, 39 cooperate to support the link 25 in position as described above, the first and third link rods 27, 34 are allowed to slide in their longitudinal directions along the inner surfaces of the corresponding hooks and the second link rod 30 is allowed to rotate around the axis Z. When the link 25 is fastened as described above, the leading end of a cantilever leaf spring 40 provided on the base plate collides with the engaging surface 28 at the tail end of the first link rod and energizes it toward the front. Consequently, the push button portion 26 at the leading end of the first link rod protrudes past the base plate and the engaging surface 35 at the leading end of the third link rod 34 whose movement is reversed through the medium of the second link rod protrudes past the rear edge of the base plate (FIG. 5(A)).
In other words, for the leaf spring 40 to manifest its energizing force already in the existing non-operative condition (the condition in which the driver's finger is not exerting pressure on the push button), the component parts of the device must be given sizes such that the leaf spring, when assembled, assumes a state slightly bent backwardly with reference to the state 40' assumed at the end of the molding indicated by the chain line in FIG. 5(A). In order that the ends of the first and third link rods may not be pushed out excessively by the energizing force of the leaf spring 40 retained in the state illustrated in FIG. 5(A), namely that the first, second, and third link rods may retain the relationship of being at substantially 90° to one another, it is desirable that the rear wall of a longitudinal groove 41 provided on the upper surface of the first link rod 27, for example, should come into contact with a stopper projection 42 on the rear surface of the base plate when the link rods assume the desired postures.
From the standpoint of the fabrication of the molding die to be used, the link 25 is desired to be injection molded in such a shape that the first, second, and third link rods will lie in a straight line in the die. In the course of the subsequent assemblage, the three portions of the straight link destined to form the link rods can be bent at angles of 90° in the prescribed directions.
Another component part to be provided for the base plate 16 is a rotary damper device 43. The rotary damper device 43 serves the purpose of applying suitable restraint to the rotary shaft of the gear 44 thereby retarding the motion produced by virtue of the rotation of the gear 44. Various types of dampers, some using mechanical friction and some others making use of oil-damping, are available. The damping devices which are disclosed in Japanese Utility Model Public Disclosure No. 56002/1981 and Japanese Utility Model Application No. 82888/1980 to be laid open to public inspection shortly are concrete examples.
The particular damping device used in the present embodiment is of the oil-damping type marketed by the assignee of the present patent application. Comprising a cylindrical housing 45 of a plastic material for admitting the rotary shaft of the gear 44, vanes or a disc fitted radially around the rotary shaft inserted into the cylindrical housing 45, and silicone oil filling the interior of the cylindrical housing 45, this damping device provides required damping by virtue of the resistance derived from the viscosity of the oil. It suffices to have this damping device 43 designed so that the gear 44 is accurately meshed with the rack gear 14 inside the housing 4 when the housing 45 of the damper device 43 is attached to the base plate 16 and the base plate 16 is incorporated into the housing 4. The damper device 43 is provided along the periphery of the housing 45 thereof with an edge portion 46. In the present embodiment, therefore, a fitting portion 47 comprising a space for accommodating the housing 45 and a space for embracing the edge portion 46 is formed in the lateral wall 17 along one edge of the base plate 16. The damper device 43 is set in position in this fitting portion 47 by being inserted sidewise therein. Particularly since the fitting portion 47 is provided with a pair of hooks 48 adapted to hold up the lower side of the edge portion 46 and catch on the front surface, this fitting work can be simply effected by allowing the damper device 43 to come into snapping engagement with the pair of hooks 48. Otherwise, some other fitting method may be adopted to suit the particular type of the damper device to be used.
After assembly of the control mechanism 5 has been completed as described above, the front parts of the lateral walls of the base plate are bent enough for the base plate to be inserted rearward into the hollow portion 6 of the housing 4, the shafts 18 to be fitted into the bearing holes 13, and the opposite ends of the coil spring 21 to slide into the respective small grooves 22, 24.
In this case, the base plate 16 is inserted as slightly slanted down to the front so that the rear end of the third link rod 34 carrying the engaging surface 35 protruding from the tail end of the base plate will assume its position between the engaging step portion 10 and the stopper step portion 11 on the rear inner wall of the housing. When the upper surface of the base plate is depressed with the hand, the lower slanted surface 49 at the rear end of the third link rod 34 collides with the raised upper surface 50 defining the engaging step portion 10. As the depression by the hand is further continued, the rear end of the third link rod 34 is lowered while being relatively pushed away forwardly by the raised upper surface 50. When the engaging surface 35 at the upper rear end is positionally aligned with the engaging step portion 10, the third link rod is again stretched out by the action of the leaf spring 40 and the engaging surface 35 is hooked on the engaging step portion 10.
As a result, the base plate 16 can be made to assume the substantially horizontal first posture by overcoming the energizing force of the coil spring 21 as illustrated in FIG. 3.
When the driver depresses the push button 26 while the first posture is retained, the base plate 16 is caused to leap up by the mechanism illustrated in FIG. 5(B). To be specific, the push button 26 is depressed with a force greater than the energizing force of the leaf spring 40 so that the spring 40 is bent backward and the first link rod is slid backward. Consequently, the second link rod 30 is rotated around the axis Z and the third link rod 34 is pulled forward. The engaging surface 35 is also retracted and released from the engagement with the engaging step portion 10 (FIGS. 5(A), (B)), with the result that the energizing force of the coil spring 21 begins to function and the base plate begins to rise. By the slight pressure which the driver gives to the push button 26 as described above, the leaf spring 40 is actuated in the course of the ascent of the base plate 16 to cause the first link rod to return to its original position, the second link rod to be rotated back to its original position, and the third link rod to slide backward and force the engaging surface 35 to protrude again.
This upward leap of the base plate 16, therefore, is stopped at the time that the engaging surface 35 collides with the stopper step portion 11 after the entire base plate has been rotated around the axis X and slanted by the angle of rotation α. Consequently, the base plate assumes the second posture as indicated by the chain line in the diagram of FIG. 3.
The connecting hinges between the first and second link rods and between the second and third link rods are not those of combined oblong holes and pins as usually found in metallic linkages. Particularly when the operating condition illustrated in FIG. 5(B) is assumed, therefore, the first and third link rods are slightly inclined relative to the axis of the straight motion. This inclination can be absorbed by the resilience of the material of the hooks 36, 37 which serve to press the respective link rods inwardly from the opposite sides. Particularly when the length of the first link rod 27 is increased amply, the driver does not feel any awkwardness in depressing the push button 26 because the angle of this inclination can be decreased and the distance of depression of the push button 26 also decreased.
When the base plate is thrown up by the depression of the push button, if the damping device 43 should be absent, the base plate 16 would be thrown up instantaneously by the abrupt action of the energizing force of the coil spring 21. Consequently, the engaging surface 35 at the tail end of the link would collide with great force into the stopper step portion 11 and, owing to the resultant impact, the base plate 16 would shake and the ashtray disposed on the base plate 16 also would vibrate even to an extent of seriously impairing the user's comfort in the handling of the ashtray device. Worse still, there is a possibility that ashes would be sent flying from the ashtray interior. The damping device is required in order to preclude the sudden leaping of the base plate and the attendant inconveniences. In actuality, since the gear 44 provided on the rotary shaft of the damping device is securely meshed with the stationary rack gear 14, the rotation of the gear 44 is effectively restrained and the upward motion of the base plate is greatly damped, enabling the user to derive the feeling of luxury from the handling of the ashtray device. Inconveniences such as that of ashes being tossed into the air, therefore, can be avoided. The engagement of the gear 44 and the rack gear 14 is not the sole effective means for damping the otherwise possible sudden motion of the base plate. For example, the same purpose can be attained by providing the two members with rubber coats or coarsened surfaces which come into frictional engagement.
Owing to the arrangement described above, the ashtray unit 1 mounted on the base plate 16 can be opened and shut at will. It is important, however, that the ashtray unit 1 should be capable of being easily released from the base plate 16 whenever the user finds it necessary to empty it of ashes and cigarette butts. This requirement can be readily fulfilled by a simple snap-action mechanism. In the illustrated embodiment, this mechanism is formed of a resilient piece 51 provided on the base plate and a recess formed in the bottom plate of the tray 2 of the ashtray unit 1. The resilient piece 51 has one side thereof fastened to the base plate and the remaining sides thereof separated from the base plate by intervening slits, so that the resilient piece 51, because of the resilience of its own material, can be readily bent in the vertical direction with the fastened end thereof as the fulcrum. The resilient piece 51 is further provided thereon with an upward prominence 52. The recess 53 is adapted to admit this prominence 52 completely. The front and rear surfaces of the prominence 52 are smoothly sloped so that the resilient piece 51 will easily be bent down whenever a force is applied horizontally thereto from either the front side or the rear side.
Further, the ashtray unit 1 is provided along the lower opposite edges thereof with guide grooves 54 formed in the direction of the innermost recess, whereas the base plate is provided along the opposite edges thereof with inwardly extended guide pieces 55. When the ashtray unit 2 is slid on the upper surface of the base plate and pushed in with the guide grooves 54 fitted into the guide pieces 55, the rear part of the bottom of the tray will collide with the front surface of the prominence 52. When the insertion is further continued despite the slight resistance offered by the prominence 52, the prominence yields to the pressure and dips and eventually finds its way into the matching recess 53. By the resilience of the resilient piece 51, the prominence 52 finally fits completely into this recess 53. The relevant parts of the ashtray unit 1 and those of the base plate are given sizes such that the front plate 3 of the ashtray unit 1 will collide with the frame portion 23 surrounding the opening of the housing precisely at the time that the prominence 52 snaps into the recess 53. Further for the purpose of avoiding excessive insertion of the ashtray and effectively keeping the ashtray from randomly rising, there may be provided a retainer piece 57 adapted to be inserted into the groove 56 in the rear part of the tray in addition to the guide pieces 55. The front plate is provided with an opening 58 through which the push button 26 passes.
When the tail end of the base plate is caused to leap upwardly as described previously by the depression of the push button while the ashtray is set in position on the base plate 16 as described above, the ashtray unit 1 as a whole is rotated at the same time to open the front surface of the tray 2 with reference to the opening of the housing. Through the gap (as indicated by the chain line in FIG. 3) thus produced, the user is free to drop ashes and cigarette butts into the ashtray. At this time, the angle of rotation α' of the ashtray unit is identical with the angle of rotation α of the base plate portion. Thus, the opening angle of the tray can be adjusted depending on the position of the stopper step portion 11 relative to the engaging step portion 10.
The closure of the ashtray can be accomplished simply by pushing the front plate 3 of the ashtray in the direction of the housing 4. In consequence of the push, the base plate 16 lowers itself by the action described already and comes into contact with the engaging step portion 10 and resumes its original state after the engaging surface 35 of the link 25 has ridden over the upper surface of the engaging step portion 10.
The removal of the ashtray from the housing can be accomplished by drawing the entire ashtray forward with a force enough for the stationary prominence 52 to bend downwardly. This removal of the ashtray can be effected more advantageously while the ashtray is kept in its opened state, because the user can get better hold of the front plate 3 when the ashtray is open than when it is kept shut.
The housing 4 is secured within an opening H formed in the panel P of the automobile as illustrated in FIG. 3. Although the method used for the attachment of the housing to the panel has no direct bearing upon the present invention, the attachment can be accomplished very conveniently by a simple snap action as illustrated in the drawing.
Specifically, from the lower surface of the housing 4, a rib 59 adapted to nip the edge of the opening H in the panel P against the lower rear surface of the front frame portion 23 is raised. First, the housing 4 held aslant is inserted into the opening H. Then, at the time that the edge of the opening is nipped between the rib 59 and the front frame portion 23, the upper end of the housing is rotated about the nipped edge as the fulcrum while the resilient engaging piece 60 provided on the upper surface of the housing and extended upwardly to the front is bent down and forced past the edge of the opening. At the time that the front frame portion 23 comes into contact with the front surface of the panel, the resilient engaging piece 60 is allowed to regain its original shape by slipping past the opening, with the result that the edge of the opening is nipped fast between the leading end 61 and the front frame portion. It should be noted, however, that the construction just described is not the sole measure available for the attachment of the housing to the panel. Optionally, the attachment may be effected by means of well-known plastic fasteners provided on the front frame portion 23 or by means of setscrews, for example.
Another embodiment of the ashtray device according to the present invention will be described with reference to FIGS. 6-10.
FIG. 6 illustrates an ashtray unit 101 which comprises a front plate 103 and a tray 102. A housing 104 for accommodating the ashtray unit 101 is illustrated in FIG. 7. The ashtray device comprising the ashtray unit 101 and the housing 104 allows the tray 102 to be opened by application of pressure to the front plate 103 of the ashtray unit. The tray 102 has the upper ends of the side walls thereof formed in the shape of an arc and is provided in the front lower portion thereof with a groove 106 (FIG. 8). The housing 104 is provided on the front lower portion thereof with a shaft 105 which extends across the housing with its ends supported by the side walls 120 and 125 of the housing. By fitting the shaft 105 of the housing into the groove 106 of the tray, the ashtray unit is attached within the housing so as to rotate around the shaft as illustrated in FIG. 8. The ashtray unit is at all times given energizing force by a spring 107 provided on the shaft 105 so as to rotate in the opening direction. On the inside of the rear wall of the tray 102, there is provided a swing plate 108 swingable around a shaft 110. The swing plate is at all times given energizing force by a spring 111 so as to be kept in an upright position. Provided on the rear surface of the swing plate 108 is a projection 109 which is slidably fitted in a groove 112 formed in the arc-shaped inside wall of the housing. When the tray is in the state of use, the projection 109 collides against the upper end portion of the groove 112, thereby preventing the ashtray unit from being rotated further in the opening direction. In taking the ashtray unit out of the housing for the purpose of cleaning etc., the swing plate 108 is pushed down against the energizing force of the spring 111, with the result that the projection 109 is kept in position inside the rear surface of the tray as illustrated by a chain line in FIG. 8. That is to say, the collision of the projection against the upper end portion of the groove 112 is released. Therefore, the ashtray unit is further rotated around the shaft 105 and can be taken out of the housing 104 by releasing the shaft 105 from the groove 106.
The tray 102 has its one side wall 119 provided with a protuberance 113 which protrudes outwardly. The corresponding side wall 120 of the housing has an arm 114 to be engaged with the protuberance 113 formed on the inner side thereof. The arm 114 has a gentle arc portion 115 formed on the rear edge side thereof and a notch 116 with first and second stepped engaging portions 121 and 122 formed in the lower end of the arc portion 115, as illustrated in FIG. 9(A). When the arm is seen from the front side, as illustrated in FIG. 9(B), the upper portion from the notch of the arm is bent to be apart from the side wall 120 of the housing further than the lower portion from the notch of the arm. The arm is supported at the lower end thereof by the side wall 120 of the housing so as to be rotatable around a shaft 117 and, as indicated by arrows "a" in FIGS. 9(A) and 9(B), it is given at all times energizing force, though weak, by a spring 118 in the directions toward a stopper 126 formed on the side wall 120 and apart from the side wall 120. The second engaging portion 122 of the notch 116 is connected to a guide groove 123 extending upwardly to have its depth decreased gradually in the upward direction.
The other side wall 124 of the tray 102 is provided with a rack gear 127 describing an arc with the groove 106 as the center and the corresponding side wall 125 of the housing 104 has a damping device 128 fixed to the outer side thereof. The damping device has a rotary shaft piercing into the wall 125 of the housing and having a pinion gear 129 at the leading end thereof. The rack gear 127 and the pinion gear 129 are meshed with each other when the ashtray unit is accommodated in the housing.
In the ashtray device of the construction as described above, the ashtray unit is always given energizing force by the spring 107 so as to rotate in the opening direction and, on the other hand, the protuberance 113 on the side wall 119 of the tray is engaged with the first engaging portion 121 of the notch 116 formed in the arm 114 of the housing so as to prevent the protuberance from moving upwardly and therefore, the ashtray unit is accommodated in the housing.
When the front plate 103 is slightly pushed in for use of the tray, the protuberance 113 is slightly moved downwardly because there is a small space between the panel P and the front plate 103. As a result, the arm 114 is slightly rotated since it is always given energizing force by the spring 118 in the direction of the stopper 126 side and the protuberance 113 comes into engagement with the second engaging portion 122 as illustrated in FIG. 9(A). However, since the second engaging portion is connected to the guide groove 123, the protuberance 113 moves upwardly along the guide groove and pushes the arm 114 gradually toward the side wall 120 side as illustrated by the chain lines in FIGS. 9(A) and 9(B) and consequently disconnects the contact with the arm 114, with the result that the arm 114 is returned to its original position. The upward movement of the protuberance 113 (arrow "b" in FIG. 9(A)) allows the ashtray unit to rotate around the shaft 105. The rotation of the ashtray unit continues until the projection 109 of the swing plate 108 collides against the upper end portion of the groove 112 of the housing and, upon completion of this rotation, the tray is in the state of use. Since the rack gear 127 of the ashtray unit and the pinion gear 129 of the damping device 128 of the housing are engaged with each other, at this time, the rotation of the ashtray unit proceeds slowly as in the first embodiment. Therefore, the ash and dust in the tray do not scatter during the rotation of the ashtray unit.
The ashtray unit 101 is accommodated in the housing 104 by pushing the front plate 103 of the ashtray unit to the housing. This pushing operation allows the protuberance 113 to descend as indicated by the chain line in FIG. 9(C). The protuberance, during its descent, comes into contact with the arc portion 115 of the arm 114 to push the arm in the direction (arrow "c" in FIG. 9(C)) opposite the direction in which the arm is energized by the spring 118 until it is engaged with the first engaging portion 121 of the notch 116 (FIG. 9(C)). When the protuberance is engaged with the first engaging portion, if the pushing force to the front plate is released, the protuberance 113 cannot be moved upwardly. Thus, the ashtray unit is kept in the state wherein it is accommodated in the housing.
As described in detail above, the present invention enables the ashtray to be opened very conveniently and safely without compelling the user to grope for the ashtray with a burning cigarette held between his fingers. It also adds notably to the feeling of luxury of the ashtray itself and enhances the commercial value of the ashtray in line with the recent trend toward high quality.
In the embodiments described above, the open-shut mechanism is based on the rotation of the ashtray unit by utilization of the pushing operation. Of course, this mechanism can be optionally modified without departing from the spirit of the invention. For example it may be based on the sliding motion of the ashtray unit by utilization of the pushing operation. | An ashtray device comprises an ashtray unit, a housing for accommodating the ashtray unit, energizing means disposed within the housing for energizing the ashtray unit in the direction of being opened, retaining means for keeping the ashtray unit in a closed state, and means for releasing the retaining means from the outside. By building the ashtray device into the dashboard of an automobile, for example, a driver is relieved of special care and allowed to devote all his attention to the operation of his automobile even during the use of the ashtray unit. | 4 |
BACKGROUND OF THE INVENTION
The present invention relates to shelters and more particularly to shelters which are portable, easily assembled and are collapsible for ease of storage.
A portable protective shelter can provide welcome relief for the person who enjoys spending time outdoors such as at the beach, lake or in the backyard, but prefers to do so without sitting in the hot sun. However, the average outdoor-oriented person does not want a portable shelter which is heavy and clumsy to carry or is complicated to assemble. A portable shelter should not unduly restrict the user's movement and vision when the user is inside the shelter.
Variour prior art portable shelters provide relief to users from the sun and the earth's elements. For example, Fulk U.S. Pat. No. 2,934,076 shows a beach cabana which is designed to be a portable, lightweight shelter for use on the beach. The Fulk patent teaches a beach cabana having three walls and a roof which can be easily folded when ready to leave the beach. This cabana generally comprises a rectangular fabric covering which is rigidly supported by three horizontal rods or tubes which are in turn held in place by a collapsible frame. The frame structure is further supported by several guy wires which are attached to steel spikes pounded into the ground.
The Moss U.S. Pat. No. 3,394,720, also shows a portable canopy or shelter which can be readily used for outdoor purposes. Moss teaches a shelter which relies upon a single resilient pole to support a single sheet of flexible material which forms the shelter. The resilient pole is received within a tunnel or sleeve which is formed in the sheet of material and extends along the peak of the shelter. The shelter further includes a base socket for receiving one end of the resilient pole with two rigid arms radiating from the socket along the ground. The shelter is formed by flexing the pole and connecting the corners of the sheet to the outer ends of the rigid arms.
The Beaudry U.S. Pat. No. 4,355,650 discloses a portable shelter including a plurality of bows attached at each end to a pair of hubs. Side braces interconnect the bows in their extended positions and are pinned to them. One edge of the shelter rests on the ground and the shelter is held in place by an anchor buried in the ground.
Unfortunately, some of the problems associated with the shelters to which the present invention relates, has been in the assembly and disassembly of the device. While some prior art shelters are readily collapsible, many rely upon guy wires for support or to anchor the structure, which not only requires tie down wires, but may also require use of different tools to secure stakes in the ground or to dig holes in the ground.
SUMMARY OF THE INVENTION
The present invention comprises a portable, collapsible shelter which can be easily assembled by one person for use as a protective covering. This portable, collapsible shelter comprises a frame means, which receives and stretches a flexible covering material which forms the protective shelter. The frame includes a tripod structure which disposes the flexible covering material completely above the ground. The frame means including the tripod support structure is interconnected by pivot means, which enables the structure to be collapsed to a small size for easy storage and carrying.
The frame means which receives and stretches the flexible covering material further includes a central support rod which supports and separates a first stretch bow and a second stretch bow which receives the flexible covering material in sleeves which are formed from looped portions in the flexible covering material. The tripod structure further includes a front support leg and two rear support legs which are connected respectively to opposite ends of the central support rod by the interconnecting means. The interconnecting means also includes fastening means for securing the first and second stretch bows to the central support rod.
While portable shelters are not new in the art, the portable, collapsible shelter of the present invention is unique because of its compact and lightweight design and its ease of assembly. The present invention overcomes problems associated with the shelters in the prior art by forming the support elements to include slidably engageable fastening devices. This invention also eliminates the need to use guy wires or other tie down devices to help support the structure.
The present invention can be used at locations which lack adequate shade, thus providing a protective cover from the sun's rays. Also, this invention can be erected in the shallow portion of a lakebed, thus permitting the user to sit in cool water while staying out of the hot sun. This portable shelter can be also used as a blind for camouflauge while hunting or it can be used as a small open-ended tent by lowering the front support leg to the ground.
Shelters constructed according to the present invention may generally be used by several persons at one time. While the shelter can remain errcted for an indefinite period, this type of shelter is usually used for the day and thereafter removed. Therefore, some of the features and advantages of such a shelter are compactness, light weight and ease of assembly and disassembly.
Portable shelters of the present invention are to be distinguished from shelters of a more permanent nature such as traditional tents. While these latter shelters are also intended to be portable and collapsible for movement from place to place, they are used more often as temporary housing or storage units, rather than a shelter from the sun. Also, these latter types of shelters are considerably larger to provide greater security for people and supplies and, therefore, require a more complex assembly.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the portable, collapsible shelter in accordance with the invention;
FIG. 2 is a perspective view showing the front interconnecting means;
FIG. 3 is a perspective view showing the rear interconnecting means;
FIG. 4 is a partial cross-sectional view showing the stretch bow and holder;
FIG. 5 is a cut away view of the jaw fastening means; and
FIG. 6 is a perspective view showing the invention in a collapsed state ready for storage.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
A portable, collapsible shelter 10 constructed in accordance with the present invention is illustrated in FIG. 1. The portable, collapsible shelter 10 comprises a flexible covering material 12 supported by a frame means which includes a central support rod 18 which supports and separates a first stretch bow 14 and a second stretch bow 16. The central support rod 18 is further supported above the ground by a tripod structure which comprises a front support leg 22 and two rear support legs 24-24'. The front support leg 22 is attached to one end of the central support rod 18 by a first interconnecting means 30. The two rear support legs 24-24' are attached to the opposite end of the central support rod by a rear interconnecting means 32.
The flexible covering material 12 includes a front sleeve 15, which receives the first stretch bow 14. The flexible covering material 12 also includes an intermediate sleeve 19, which receives the second stretch bow 16. The flexible covering material 12 extends from the second stretch bow 16 and is attached at spaced apart points to the rear support legs 24-24' by a fastening means such as the hooks 27 and 28.
The stretch bows 14 and 16 are utilized to stretch the covering material 12 into the desired position for use as a shelter and to retain it in that position during use without the necessity of guy wires or support legs at the corners of the shelter material 12, as has been required by prior art devices. The stretch bows are held in place at each end of the central support rod 18 (as will be more fully described hereinafter), and the flexible covering material 12 is held in place on the stretch bows by a grommet disposed in the outer edges of the material 12 at positions such that the ends of the stretch bows can be inserted into a grommet, thereby causing the stretch bows to assume the desired curved shape and properly hold the material in position. As was previously indicated, the remaining corners of the flexible covering material 12 may be secured to the supporting frame member by the hooks 27 and 28 being secured to the rear legs 24-24' respectively.
The front support leg 22 includes two separate leg portions 22a and 22b which are slidably received one within the other. The leg portion 22a can be fastened within the leg portion 22b by a spring loaded tab or button 25 which protrudes through an opening 27 which is defined by the leg portion 22b. Several positions on leg portion 22b can be provided to adjust the length of the front support leg 22 depending upon the weather and terrain conditions. Two separate rear leg portions 24a, 24b and 24'a-24'b can be slidably received one within the other to form the rear support legs 24-24'. Again, the leg portions can be fastened within one another by a spring loaded tab 25' which can protrude through an opening 27' which is located on each respective leg portion. Again, such a structure allows the user to adjust independently the length of each of the tripod legs to accommodate the particular conditions of use.
The front support leg 22 and the two rear support legs 24-24' can be held down in the event of wind by bags 26 which can be filled with materials such as sand, dirt or rocks and attached to each respective leg by a fastening means 29. The fastening means 29 can be a simple strap and hook which fits into a hole 31 located near the bottom of each support leg.
FIGS. 2 and 3 illustrate the means by which the tripod legs 22 and 24-24' are attached to the central support member rod 18. As will be noted the legs 22 and 24-24' are pivotally connected to the rod 18, thereby permitting total collapse of the legs into alignment with the support rod 18, as well as the telescoping of the legs as above described to thereby provide reduction of the support members to a small and readily handable size for storage and transportation. In addition, the front leg 22 may be pivoted into alignment with the rod 18, thereby allowing the user to lower the stretch bow 14 into contact with the ground. As will readily be seen, this provides a means of some security for items which may be left by the user at a particular site when they are gone. Alternatively, this ability to lower the stretch bow 14 into contact with the ground may be utilized in the event of particularly high winds that may otherwise tend to raise the entire structure into the air, even though the anchoring means is in position. In addition, the shelter when thus lowered can be used as a small open-ended tent.
Again, referring to the preferred embodiment of the portable collapsible shelter 10 as shown in FIG. 1, the central support rod 18 comprises two rod portions 18a and 18b which are slidably engaged and disengaged one within the other to provide an even more compact size for storing the shelter. The frame means may be constructed of any desired material, but preferably is fabricated from galvanized steel or aluminum poles. The stretch bows 14 and 16 are preferably constructed from a flexible material such as fiberglass. The flexible covering material 12 is preferably polyurethane coated nylon.
By reference to FIG. 4 there is illustrated in detail the construction of the stretch bows 14 and 16. As is therein shown, a stretch bow, for example bow 14, includes sections 14a and 14b which are interconnected and held togeter by a flexible elastic member 17 through the use of a sleeve 38 constructed of a metallic cylinder which is frictionally held in place to bridge a gap between the sections 14a and 14b of the stretch rod. That is, when the two ends are permitted to come together by allowing the elastic 17 to pull them together the sleeve 38 may be slidably moved from the position shown in FIG. 4, so that it totally bridges the gap between the sections 14a and 14b. Stretch bow 16 is constructed similarly to stretch bow 14. In this manner the tubular sleeve or sheath completes the stretch bows 14 and 16 as will be readily recognized by those skilled in the art. When the shelter is being dismantled and stored the sleeve 38 can be moved to the position shown in FIG. 4, and as a result of the elastic member 17, the two portions 14a and 14b of the stretch bow 14 (and the similar construction for stetch bow 16) can then be brought together thereby allowing the flexible covering material 12 to be effectively rolled up about the stretch bows, the support rod 18 and the legs 22 and 24-24', all of which are brought together and lie along the same general line as does the central support rod 18. It is through this unique combination of elements and the manner in which they are pivoted together and easily collapsed that provides the unique, lightweight portable and easily stored shelter of the present invention.
Referring again to FIGS. 2 and 3, the means for securing the stretch bows 14 and 16 in position upon the central support rod 18 are more fully illustrated. As is shown, for example, in FIG. 2 the front leg 22 is pivotally secured between plates 33 and 34 by a pin 35. Each of the plates 33 and 34 defines a notch or recess 36-36' which effectively defines a channel in which the cylindrical sleeve or sheath 38 is disposed, thereby to retain the stretch bow 14 in position. A securing means such as a tongue 40 is pivotally secured by a pin 42 to the plates 33 and 34 and includes a downwardly (as viewed in FIG. 2) directed flange 41, which overlaps the cylindrical sleeve or sheath 38, thereby to securely fasten the stretch bow 14 to the frame means.
As is more clearly shown in FIG. 2, the leg 22 is held in place when the shelter is in its erected position by a spring loaded detent 43, which is received within an opening 45 provided in the plate 33. A similar detent and opening is provided on the plate 34, but is not illustrated in FIG. 2. The central support rod 18 is also disposed between the plates 33 and 34, and is held in place by a fastening means, such for example as rivets 37 and 39. The top portion of the central support rod is positioned below the top of the plates 33 and 34 by an amount sufficient to allow the pin 42 to easily extend between the plates 33 and 34, thereby allowing the tongue 40 to easily pivot from the position shown on FIG. 2 to an upwardly raised position, whereby the stretch bow 14 could be removed from notches 36-36'.
As shown more clearly in FIG. 3 the rear legs 24-24' are supported between plates 52, 54 and 56. Again the central support rod 18 is held in position between the plates 52 and 54 by fastening means, such as rivets 58. The leg 24' is pivotally secured through the plate 52 by a pin 60 and when the shelter is in its erected position, the leg 24' is held in its position by the spring loaded detent 62, which extends through the opening 64 provided in the plate 52. A similar structure enables the leg 24 to be secured to the plate 54.
That is more clearly shown in FIG. 3a, which is a view taken internally of the structure shown in FIG. 3. An additional plate 66 is secured to the plate 56 by fastening means such as the rivets 68. The plate 66 provides additional support for the legs 24-24', as is seen, and provides additional means for anchoring the pivot pins, about which the legs rotate when erecting or collapsing the structure.
An additional securing means such as the tongue 70 is pivotally attached by the pivot pin 72 between the plates 52 and 54. The tongue 70 has a downwardly directed flange 74, which secures the rear stretch bow 16 in place within a channel formed by appropriate notches or recesses formed within the plates 52, 54 and 56. As is illustrated generally at 76, the function of the securing means 70 is precisely the same as the securing means 40, and thus additional description thereof is not deemed required.
An alternative arrangement to the tongues 40 and 70 used in the front and rear interconnecting means 30 and 32, is a pair of spring loaded jaws 78, which are shown in FIG. 5. These spring loaded jaws 78 can be retracted to receive the cylindrical sleeve 38 and then close to secure the stretch bows in place. As is shown in FIG. 5, these spring loaded jaws 78 can be located in the same location where the tongues are positioned.
FIG. 6 shows the perspective view of the portable collapsible shelter 10 as it would look when ready for storage in its hand-carry bag 48.
The present invention comprises a compact, lightweight shelter which is easy to assemble. When fully assembled, this invention provides an attractive protective shelter for several people.
While the above invention has been described in accordance with the preferred embodiment, it should be understood that various changes and modifications can be made in the specifications of the invention without detracting from the invention in its broadest form. | A portable shelter having a tripod-type frame for supporting a fabric cover along the center thereof with the cover being spread by stretch bows retained upon the frame. Each of the legs of the tripod is adjustable as to height and pivot to provide a compact structure easily stowed in a hand-carry bag. | 4 |
TECHNICAL FIELD
[0001] The present invention relates to a database index and a database for indexing text documents.
THE PRIOR ART
[0002] Today, huge amounts of text documents are typically stored in large databases in order to facilitate an efficient retrieval of the contents of the documents using database query mechanisms. Such documents may be structured and comprise text as well as non-text contents. Native XML databases have become increasingly popular in this context.
[0003] In order to efficiently retrieve documents with a specific text from the database, scanning all documents for the searched text is highly inefficient given the possibly huge amount of documents and the large amount of text of each document. In this context, indexes are commonly used. Such indexes typically manifest as lists of key/value-pairs, wherein the keys store the information to be searched and the values store a list of pointers towards documents which contain the searched information. In the context of text document retrieve, the keys typically each store a word comprised in the text of the documents. Maintaining such a text index significantly enhances the performance of queries that search for all documents containing a specific word, which is a common use case.
[0004] However, such a prior art index only satisfyingly improves the efficiency of simple queries for text documents which contain a single word anywhere in the document. In more advanced contexts, more complex queries are needed, for example for retrieving documents which
contain a number of words with a given distance (e.g. only two consecutive words), contain words in a specific location of the document, or a combination of both, i.e. retrieving a number of words with a given distance in a specific location of the document.
[0008] In the prior art approaches are known for designing an index in a manner which facilitates an efficient retrieval in one of the above use cases, but which is rather inefficient in other use cases. Since maintaining multiple indexes in parallel for different types of queries is costly and requires much processing time and storage space, there is a need for a common indexing structure which is efficient in all of the above use cases.
[0009] For example the U.S. Pat. No. 7,305,613 discloses a method and an apparatus for indexing structured documents. Among several infrastructure functions such as concurrency control and version control, the document teaches how to generate indexes storing index values according to certain predefined extraction rules. The entries of the generated indexes are preferably stored in a tree-like structure and comprise one indexed word each.
[0010] In contrast to improving the processing speed of a given query with the help of an index, whose generation takes place prior to the actual execution of a query, other prior art approaches propose to optimize the query itself at runtime. For example, the U.S. Pat. No. 7,305,414 discloses a method and an apparatus for rewriting database commands containing embedded XML expressions in order to improve the efficiency of query processing. Such queries may also involve indexes, however, how these indexes are structured is outside the scope of the document.
[0011] Furthermore, in the field of text retrieval in large document collections, the U.S. Pat. No. 7,305,380 defines a system that limits the search results of a search engine based on context information such as URLs, in order to provide a user with more relevant search results. The system may also involve indexes for executing queries, however, how such indexes are best structured is not discussed. Lastly, the U.S. Pat. No. 7,305,336 discloses a method for summarizing text in documents, in that the method analyzes the text for semantic relationships and compresses the documents by deriving generalizations that summarize parts of the text. However, improving the processing of queries over such texts is not discussed.
[0012] It is therefore the technical problem underlying the present invention to improve the efficiency when searching a database for text documents which at least partly overcomes the above explained disadvantages of the prior art.
SUMMARY OF THE INVENTION
[0013] This problem is according to one aspect of the invention solved by a database index for indexing one or more text documents in a database, the text documents comprising one or more hierarchical nodes each comprising one or more words. In the embodiment of claim 1 , the database index comprises at least one entry, each entry comprising:
a. a key comprising a subset of words occurring in one of the hierarchical nodes of the text documents and the name of the respective hierarchical node; and b. a value comprising one or more references to the text documents in which the subset occurs.
[0016] Accordingly, the embodiment defines a database index which stores key/value-pairs as its entries. Each key stores a tuple which comprises a subset of words occurring in one of the hierarchical nodes and the name of the respective node, i.e. it combines text (the subsets of words) and structure (the name of the nodes) information. This enables efficient queries for text documents which comprise certain words in a specific location. To this end, the entries of the database index are scanned for a key which comprises the searched words and the searched node name. If the database index comprises an entry with this key, the corresponding value is obtained. This value references the text documents of the database which comprise the searched words in the searched location. A database index combining text and structure information according to the present invention enables a huge efficiency improvement in multiple use cases, as further outlined in the detailed description below.
[0017] In one aspect of the present invention, each key may be ordered by the first word of the subset of words, the name and the remaining words of the subset of words. Accordingly, the keys of the index are in this aspect ordered tuples of the form (w1, A, w2, . . . , wn) with w1, w2, . . . , wn being the indexed words and A being the node comprising these words. The ordering of an index has direct impact on the speed of information retrieval. Ordering an index like illustrated above is especially advantageous, as further explained in the detailed description below.
[0018] In another aspect, the entries may be sorted by the first word of the subset of words in alphabetical order, by the name in document order and/or by the remaining words of the subset of words in alphabetical order. Sorting the entries of an index in a certain manner further improves the efficiency of information retrieval, as explained in the detailed description below.
[0019] Furthermore, the subset of words in each key may comprise only one word. Accordingly, if for example a node A to be indexed comprises three words w1, w2 and w3, the database index would comprise three entries for the node A whose keys are each built from the subsets {w1}, {w2} and {w3} respectively, each combined with the name “A” as explained above.
[0020] Alternatively, the subset of words in each key may comprise at least two words having a predefined distance from each other in the text of the text documents. The distance thus reflects the number of words between two words. In one aspect, the at least two words may be consecutive words, i.e. having a distance of 0. In the above example of a node A with three words w1, w2 and w3, the database index would comprise two entries for this node whose keys comprise the subsets {w1, w2} and {w2, w3}, respectively. The subset {w1, w3} would not be included in the index, since the words w1 and w2 are not consecutive words. Furthermore, it should be noted that if the last word w3 is stored in an entry {w3, □}, where □ is a special end-token, the resulting two-word-index has as many entries as the single-word-index shown further above. Consequently, the effort when inserting a new text document in the database and adding a corresponding entry to the index is the same for both index structures.
[0021] In yet another aspect of the present invention, the name in each key may comprise a path of the respective hierarchical node. The path may start from the root node of the text document.
[0022] In another aspect, only a part of the hierarchical nodes of the text documents may be indexed. Accordingly, a database index over books of a library may e.g. only index the bibliographic information of the books, but not the full text. Alternatively, all of the hierarchical nodes of the text documents, i.e., the full content, may be indexed.
[0023] The present invention also relates to a method for generating any of the database indexes described above, as well as to a computer program comprising instructions for implementing such a method.
[0024] Furthermore, a database, especially an XML database, being adapted for storing XML documents is provided comprising at least one database index as described above. Such a database may further comprise a structure index, as e.g. defined in the U.S. Pat. No. 7,051,016 of Applicant.
SHORT DESCRIPTION OF THE DRAWINGS
[0025] In the following detailed description, presently preferred embodiments of the invention are further described with reference to the following figures:
[0026] FIG. 1 : An exemplary text document comprising three hierarchical nodes and a database index according to an embodiment of the present invention;
DETAILED DESCRIPTION
[0027] In the following, presently preferred embodiments of the invention are described with respect to an exemplary text document 10 called doc 1 as schematically shown in FIG. 1 . As can be seen, the document 10 is structured by three nodes 10 a , 10 b and 10 c , wherein the child nodes 10 b and 10 c comprise text in the form of sequences of words 20 a - 20 c and 20 d - 20 f , respectively. Although FIG. 1 shows only an extremely simple document 10 , it should be appreciated that the present invention is especially advantageous in databases storing huge amounts of much more complex text documents with any number of nodes in arbitrary depth, each node possibly comprising thousands of words. The text documents 10 may be XML documents and the database storing the documents 10 may be a native XML database. However, it should be appreciated that the present invention covers any type of text documents 10 in a wide variety of formats, XML being only one example. Furthermore, in the example of FIG. 1 , only the leaf nodes of the text document 10 comprise words. However, it should be appreciated that text documents 10 which comprise words in any level of the node tree are also supported, i.e. any node may comprise text, further child nodes or both. This is called “mixed content” and is especially advantageous in scenarios related to huge text documents.
[0028] In the following, a number of use cases, i.e. kinds of queries, as well as different prior art approaches for defining indexes supporting these use cases are presented. Furthermore, the efficiency of the database indexes according to the present invention are compared to these prior art approaches in the different use cases.
[0029] In the prior art, a simple query asking for documents containing the word “word 1 ” would find the document 10 with little effort by using the following single-word-index:
[0000] word1 →doc1, →doc2, →doc3, . . . word2 →doc1, →doc2, →doc4, . . . . . . . . .
As can be seen, the single-word-index stores single words as keys as well as pointers, i.e. references, towards documents which contain the words as values. The key/value-pairs may be sorted alphabetically.
[0030] Maintaining such an index, however, may make updating operations slower. Inserting a new document, for example, requires going through every word contained in the new document and adding the information that this word occurs in this document to the index.
[0031] Another common use case is a search for documents that contain a set of words in a predefined distance from each other, i.e. with a predefined maximum amount of words in between. The most frequent of these use cases is the search for two consecutive words, i.e. word-pairs with a distance of 0.
[0032] Such a query that looks for documents containing “word 1 ” directly preceding “word 2 ” could use the above single-word-index. First, the single-word-index would be scanned for “word 1 ” and then another index-scan would be performed for “word 2 ”. In the example document 10 of FIG. 1 , the single-word index would find the document 10 twice because it contains both words. Afterwards, the document 10 would need to be scanned in detail in order to find out if the words occur in the required sequence. However, such a document scan is time consuming and processing intensive, especially for large documents.
[0033] The use case may be handled more efficiently by an index that contains each pair of two consecutive words occurring in any document, i.e. a double-word-index. Although the resulting index table is bigger than the table of a single-word-index as shown above, the effort when inserting a document into the database is the same since a document contains as many word pairings as it contains words, given that the last word is preferably inserted as a pairing of (word, “end-token”). The index entries may be sorted alphabetically firstly by the first word and secondly by the second word, as depicted in the following exemplary prior art double-word-index:
[0000] word1, word2 →doc1, →doc2, . . . word2, word3 →doc1, . . . . . . . . .
Queries looking for two consecutive words can be speeded up considerably using this index, since the double-word-index provides this information with only a single index lookup and no document scanning afterwards.
[0034] Queries for a single word as shown further above in the context of the single-word-index can be handled in the same way using the double-word-index, in that just the first entry that contains the required word in the first position of the key is retrieved.
[0035] It should be appreciated that the above presented concept may be expanded for indexes comprising word triplets or even larger tuples, accordingly.
[0036] A slight disadvantage when replacing a single-word-index with a double-word-index is that since the latter contains more elements in its keys, finding the appropriate key may take slightly longer. However, this drawback is acceptable, since the additional effort needed is far less than the cost of a document scan.
[0037] Both indexes discussed above retrieve words regardless of where they occur within the documents. Queries frequently, however, ask for documents that contain a word in a specific position If, for example, as depicted in FIG. 1 , each document 10 of a certain collection consists of nodes 10 a, 10 b and 10 c called A, A/B and A/C, respectively, a query might ask for documents that contain a specific word in an A node. An index that would directly support an efficient querying of this kind needs to contain pairings of words and a location specification, as depicted in the following word-structure-index according to the present invention:
[0000]
word1, A
→doc5, . . .
word1, A/B
→doc1, →doc3, . . .
word2, A
→doc2, . . .
. . .
. . .
[0038] The above word-structure-index would provide the information that “word 1 ” occurs in doc 1 /A/B very efficiently with a single index scan. In contrast, the prior art single-word-index would only provide the information that “word 1 ” is contained in doc 1 somewhere and the document would subsequently need to be scanned in detail to find out in which of the nodes “word 1 ” occurs, which is inefficient, as already explained above. The word-structure-index may be sorted first by the words alphabetically, and then by the structure elements in document order. This word-structure-index has a number of advantages:
[0039] First, the use case when looking for a single word regardless of the position within the document can still be handled efficiently by just looking for the first occurrence of an entry that contains this word.
[0040] Furthermore, the overhead for index maintenance when inserting a document is small. When a (word, document-pointer)-pair is inserted into the index, the position the word is currently found in is known, thus additionally adding the position information needs no further query steps.
[0041] Another common kind of query is asking for consecutive words at certain positions. Accordingly, the present invention facilitates the generation of indexes combining the double-word-index and word-structure-index. Since both extensions add little overhead to the index maintenance costs, the combination of both extensions has comparable maintenance costs. An example of such a combined double-word-structure-index according to the present invention is depicted below:
[0000]
word1, word2, A
→doc5, . . .
word1, word2, A/B
→doc1, →doc3, . . .
word2, word3, A
→doc2, . . .
. . .
. . .
[0042] The index may be ordered by the first word alphabetically, the second word alphabetically and then by the structure information in document order.
[0043] With the above depicted double-word-structure-index, a query asking for the sequence (word 1 , word 2 ) at position A/B in doc 1 can be handled very efficiently with a single index lookup. This index can still handle queries asking for single words at arbitrary positions by finding the first key that contains the respective word at the first position. Queries that look for consecutive words at arbitrary positions can be handled by finding the first entry that contains the words at the first and second position.
[0044] A disadvantage arises in the use case of looking for a single word at a specific position. The index lookup would try to find the first entry that contains the word at the first position and the appropriate structure information in the third position. In other words, all index entries that start with the word currently searched for must be looked at. This is rather disadvantageous, since in databases holding text documents with large text contents, a certain word can occur very often with different successors and thus the set of index entries staring with a single word may be very large.
[0045] Therefore, a presently preferred embodiment of the invention provides an index whose keys are ordered to contain the structure information in the middle, as shown below:
[0000]
word1, A, word2
→doc5, . . .
word1, A, word3
→doc6, . . .
word1, A/B, word2,
→doc1, →doc3, . . .
word2, A, word3
→doc3, . . .
. . .
. . .
[0046] This word-structure-word-index is preferably ordered by the first word alphabetically, the structure information in document order and the second word alphabetically.
[0047] This preferred index structure is very efficient when handling queries for sequences of words in a specific position and queries for single words in arbitrary positions, similarly to the double-word-index presented above. Additionally, queries for a single word at a specific position can find the appropriate index entry also very efficiently, it is the first entry with suitable word at the first position and suitable structure information at the second position.
[0048] On the other hand, the use case of looking for word-pairings regardless of the position seems slightly less efficient as with the above double-word-structure-index. Such a query would with the word-structure-word-index need to look at every entry that contains the respective word in the first position and must scan these entries for their third entry. This disadvantage, at a closer look however, is minimal for two reasons:
[0049] Firstly, the number of entries that have to be scanned is typically small since it must by definition be smaller than the number of nodes occurring before the node currently searched for in document order. The number of nodes occurring in a document is in general much smaller than the number of words occurring subsequent to a specific word in a collection of text documents.
[0050] Secondly, if the database maintains a structure index, i.e. information about which nodes actually occur both in a specific document and in a collection of documents, the query execution engine can easily lookup which (and especially how many) entries must maximally be inspected on account of a query. Thus, the engine can optimize the query much better for best performance. A structure index helpful in this context is e.g. defined in the U.S. Pat. No. 7,051,016 of Applicant.
[0051] Although the above examples only show indexes according to the present invention which comprise pairs of consecutive words, it should be appreciated that the advantageous concepts can easily be expanded for indexes serving queries for any number of words with a defined distance.
[0052] In summary, the present invention defines an advantageous indexing structure combining text and structure information, which facilitates a very efficient information retrieval especially in large text document collections. Moreover, indexes defined according to the present invention in the form of simple, well-proven list-based indexes are very efficient even when used in different scenarios, comprising queries for single words in arbitrary positions, single words in specific document positions, multiple words in arbitrary positions as well as multiple words in specific positions. | The present invention concerns a database index for indexing one or more text documents ( 10 ) in a database, the text documents ( 10 ) comprising one or more hierarchical nodes ( 10 a, 10 b, 10 c ) each comprising one or more words ( 20 a, 20 f ), the database index comprising at least one entry ( 50 ), each entry ( 50 ) comprising:
a. a key ( 51 ) comprising a subset ( 510 ) of words occurring in one of the hierarchical nodes ( 10 a , 10 b, 10 c ) of the text documents ( 10 ) and the name ( 511 of the respective hierarchical node ( 10 a, 10 b , 10 c ); and b. a value ( 52 ) comprising one or more references ( 520 ) to the text documents ( 10 ) in which the subset ( 510 ) occurs. | 6 |
TECHNICAL FIELD
[0001] The aspects of the disclosed embodiments generally relate to a computer implemented method and system for training a subject's articulation.
BACKGROUND OF THE INVENTION
[0002] Producing speech sounds requires coordination of air flow from the lungs with movements of the tongue, lips and jaw. Expiration passes through the vocal cords towards the oral and/or nasal cavity where it comes into contact with the tongue and lips. Oscillation of the vocal folds converts expiratory air into intermittent airflow pulses that result in voiced sounds. If the vocal folds are open, allowing air to pass unobstructed, they do not vibrate. Sounds produced this way are voiceless.
[0003] The pharyngeal, oral, and nasal cavities of the upper respiratory tract act as resonant chambers which transform the airstream into recognizable sounds with special linguistic functions whose main articulators are the tongue, jaw and lips. Together these generate patterned movements to alter the resonance characteristics of the supra-laryngeal airway. Coordination of all these enables us to perfectly pronounce phonemes, morphemes, syllables, words and sentences in any language.
[0004] This coordination is regulated by neural networks in the central nervous system that control both articulation (the sounds themselves) and phonological processes (patterns of sound). For example, certain neurons in a particular network control the tongue to move in a certain way into a certain position and likewise send signals to the lips and jaw to take specific forms and positions as needed.
[0005] When optimizing pronunciation or perfecting an accent, new neural networks must be established so as to produce new speech sounds properly. It is not enough to rely on previously developed native-language neural networks; an entirely new set of neural networks must, through mimicry and training, be created later in life, when language learning is more labored than in childhood.
[0006] Patients suffering from speech disorders or speech impairments also benefit from rebuilding of speech-related neural networks that either never developed sufficient due to congenital deficiencies, or are the result of brain injuries or diseases that impair coordination of the speech organs.
SUMMARY OF THE INVENTION
[0007] The present invention provides method and system for establishing new neural networks in human subjects as well as repairing or replacing damaged or inadequate ones. The methods provide an effective tool for improving articulation and pronunciation as well as for treating speech disorders. Thus, the methods provided herein relate to training and/or improving a subjects' articulation, e.g. for learning a foreign language or for training or training down an accent. Moreover, the invention may also relate to medicine, namely to neurology and speech therapy. Methods can be provided for the rehabilitation of patients with speech disorders or speech impediments.
[0008] The methods and systems described herein can be implemented using a computer program product having a program code that enables users to work independently and at their own pace.
[0009] In this aspect, a computer program product having a program code causing a computer to implement the method described herein is provided.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 provides a schematic illustration of a system for training a subject's articulation.
DETAILED DESCRIPTION OF THE INVENTION
[0011] Unless defined otherwise, all technical and scientific terms used herein have the same meanings as commonly understood by one of ordinary skill in the art to which this invention belongs.
[0012] Although similar or equivalent methods and materials to those described herein can be used in the practice or testing of the invention, suitable methods and materials are described below. All publications, patent applications, patents, and other references mentioned herein are incorporated by reference in their entirety. In case of conflict, the present specification, including definitions, will prevail. The materials, methods, and examples are illustrative only and not intended to be limiting.
[0013] The term “speech impediments” as used herein comprise, accent, lisping and slurred speech.
[0014] The term “speech disorder” as used herein comprises, without being limited to, apraxia of speech and developmental verbal dyspraxia. Apraxia of speech (AOS) is a neurologic speech disorder wherein the subject has an impaired capacity to plan or program sensorimotor commands necessary for directing movements resulting in the correct articulation of speech sounds. Patients suffering from apraxia typically show symptoms of inconsistent articulatory errors and groping oral movements to locate the correct articulatory position. With increasing word and phrase length, errors increase. Adults as well as children may be affected. Adult subjects often acquire a apraxia through lesions of the brain, e.g., due to stroke, tumors, acquired brain injuries, or neurodegenerative diseases, including, without being limited to, Cerebral infarction, Parkinson's disease, Alzheimer's disease, Brain tumors or Huntington's disease.
[0015] In some embodiments, apraxia of speech is accompanied by aphasia. In some embodiments, apraxia of speech is accompanied by oral apraxia, i.e., the inability to perform volitional tasks with the oral structures not involving speech, including puckering the lips.
[0016] A “speech sound” as used herein comprises, without being limited to, a sound, a phone, a phoneme or a morpheme. A “sound” may be a vowel or a consonant and/or combinations thereof.
[0017] The term “speech sound unit” as used herein comprises, without being limited to, a sound, a phone, a phoneme, a morpheme, a syllable, a word and/or a sentence or combinations thereof. It may include several speech sounds as defined above.
[0018] Various aspects of the invention are described in further detail below. It is understood that the various embodiments, preferences and ranges may be combined at will. Further, depending of the specific embodiment, selected definitions, embodiments or ranges may not apply.
[0019] A computer implemented method and system for training a subject's articulation, comprising the steps of:
receiving subject speech audio data of speech of the subject; accessing standard speech audio data; analyzing the subject speech audio data to determine at least one articulatory parameter deviation between the standard speech audio data and the subject speech audio data; playing a display of standard speech articulatory motion at a display speed for training the subject; adapting the display speed based on the at least one articulatory parameter deviation. receiving subject speech audio and video data of speech of the subject; accessing standard speech audio and video data; analyzing the subject speech audio and video data to determine at least one articulatory parameter deviation between the standard speech audio and video data and the subject speech audio and video data; playing a display of standard speech articulatory motion at a display speed for training the subject.
[0028] In this aspect, a computer program is provided which comprises code means adapted to, when executed on a computer, performing methods as described herein. The methods are useful for improving a human subject's articulation. In some embodiments, the method comprises receiving subject speech audio data of speech of the subject. In embodiments, the speech audio data includes a speech sound unit dataset. In embodiments, the method also includes receiving subject speech video data of speech of the subject. In some embodiments, the video data includes a tongue movement dataset corresponding to a tongue movement deconstructed from the speech sound unit, a lip and/or jaw movement dataset corresponding to a lip and jaw movement deconstructed from the speech sound unit and/or an airstream generation dataset corresponding to an airstream generation deconstructed from the speech sound unit.
[0029] In embodiments, the method includes playing a display of standard speech articulatory motion at a display speed for training the subject. In embodiments, the playing step is via a user interaction structure (e.g. display and speakers). The standard speech articulatory motion pre-defines an extended tongue time interval associated to the tongue movement, an extended lip time interval associated to the lip and jaw movement and an extended airstream time interval associated to the airstream generation.
[0030] In embodiments, the playing step includes providing a visual representation of the tongue movement dataset over the predefined extended tongue time interval. In embodiments, the method includes capturing a motion of a tongue of the subject during the extended tongue time interval (e.g. using a video camera or other sensor (such as Electromagnetic Articulograph (EMA), motion capture sensors, etc.).
[0031] In embodiments, the playing step includes a visual representation of the lip and jaw movement dataset over the predefined extended lip time interval. In some embodiments, motion of a lip of the subject is captured during the extended lip and jaw time interval.
[0032] In embodiments, the method includes analyzing the subject speech audio and video data to determine at least one articulatory parameter deviation between the standard speech audio and video data and the subject speech audio and video data. The analyzing step includes comparing the captured motion of the lip and jaw of the subject to the lip and jaw movement dataset to determine at least one articulatory parameter deviation.
[0033] In embodiments, the method includes adapting the display speed based on the at least one articulatory parameter deviation if a deviation between the captured motion of the lip of the subject and the lip and jaw movement dataset is identified. In embodiments, the adapting step includes decreasing the predefined tongue time interval, the predefined lip time interval and the predefined airstream time interval.
[0034] In embodiments, the playing step includes providing a visual representation of the airstream generation over the predefined extended airstream time interval, decreasing the predefined tongue time interval, the predefined lip time interval and the predefined airstream time interval.
[0035] In some embodiments, the method includes repeating the receiving, analyzing, playing and adapting steps.
[0036] The visual representations in the playing step can particularly be provided on a screen of the computer running the computer program.
[0037] The user interaction structure can be a graphical user interface (GUI) or any other user interface.
[0038] For capturing the motion of the subject's lip and optionally the subject's tongue a camera can be used. Alternatively or additionally, the lip and/or tongue can be provided with motion sensors. The computer program then evaluates a signal of the camera and/or of the motion sensors for the comparison.
[0039] The method has the effect that the subject is enabled to correctly and efficiently coordinate the movements required for a target articulation of a speech sound unit. After identifying a speech sound unit to exercise, the according unit is deconstructed into a tongue movement, a lip and jaw movement and an airstream generation. An extended time interval is associated to each of the movements and airstream generation. The subject then performs the different movements and airstream generation in any order over the extended time interval, i.e., the subject performs a predefined movement and/or airstream generation in slow motion. The predefined tongue time intervals are decreased as to finally reach a time interval identical to a real time interval of the speech sound unit. The term “real time” as used herein can relate to timing of an average native speaker in everyday speak.
[0040] The speech sound unit may be a sound, a phone, a phoneme, a morpheme, a syllable, a word and/or a sentence or a combination thereof.
[0041] In one embodiment, a visual representation of the tongue movement is provided to the subject in a visual representation of the lip and jaw movement is provided to the subject and/or a visual representation of the airstream generation is provided to the subject. Such visual representations may e.g. be provided by means of pictures, sketches, video, computer animations or a computer program as disclosed herein.
[0042] Preferably, said visual representations in the playing step involve a color coding corresponding to the intensity of the respective movement. The intensity of the movement refers to the extension of the motion of the articulator i.e., the tongue or the lips, in a specific direction.
[0043] Thus, in one embodiment, said visual representation of the tongue movement comprises a color coding corresponding to an intensity of the tongue movement.
[0044] In one embodiment, said visual representation of the lip and jaw movement comprises a color coding corresponding to an intensity of the lip and jaw movement. In one embodiment, said visual representation of the airstream generation comprises a color coding corresponding to an intensity of the airstream generation.
[0045] Preferably, the visual representation of the tongue movement comprises a slowed tongue movement of the speech sound unit and the visual representation of the slowed tongue movement is accelerated, and/or the visual representation of the lip and jaw movement comprises a slowed lip and jaw movement of the speech sound unit and in step (g) the visual representation of the slowed lip and jaw movement is accelerated. Like this, the visual representation of the tongue movement can comprise a series of slower than normal tongue movements of the speech unit, which with time can then be gradually accelerated back to a standard pace or everyday pace, as the performance of the subject improves. Similarly, the visual representation of the lip and jaw movement can comprise a series of slower than normal the lip and jaw movements of the speech unit, which with time can then be gradually accelerated back to a standard pace or everyday pace, as the performance of the subject improves. Such slowed visual representation(s) allows the deconstructed elements of the speech sound unit to be exercised in detail which makes an accurate improving of the subject's articulation possible.
[0046] Furthermore, preferably, the visual representation of the tongue movement comprises a repeated tongue movement of the speech sound unit, the visual representation of the lip and jaw movement comprises a repeated lip and jaw movement of the speech sound unit and/or in step (f) the visual representation of the airstream generation comprises a repeated airstream generation of the speech sound unit. Such repeated visual representation(s) allow the deconstructed elements of the speech sound unit to be isolated and exercised which enable an efficient practice and fast improvement of the subject's articulation possible.
[0047] In preferred embodiments, an acoustic representation of the speech sound unit is provided to the subject over the predefined tongue time interval, over the predefined lip time interval and/or over the predefined airstream time interval.
[0048] In some embodiments, are repeated until the predefined tongue time interval, the predefined lip time interval and the predefined airstream time interval are identical to a real time interval of the speech sound unit. Thus, the subject may in some embodiments gradually decrease the respective time intervals until the real time interval of the speech sound unit is reached. The number or repetitions may vary. In some embodiments, additional steps of repetition for any of the method alone are included, as the subject may have particular difficulties. The computer implemented system will identify these difficulties and optimize the repetition and the playing speed, depending on the performance of the subject.
[0049] In some embodiments, a chronological overlap between the tongue movement, the airstream generation and the lip and jaw movement. Accordingly, the tongue movement is accompanied by the airstream and/or the lip and jaw movement or the lip and jaw movement is accompanied by tongue movement and/or the airstream. In a preferred embodiment, there will be a chronological overlap all these three movements. The computer implemented system will optimize the overlap depending on the performance of the subject.
[0050] In one embodiment, the method further comprises the step of identifying a severity of an articulation defect of the subject. For example, a severe articulation defect may require a longer extended time interval, i.e. in a slower pace, and/or an increased number of repetitions. The articulation defect may be a speech disorder, speech impairment or an accent.
[0051] This computer implemented system will efficiently support establishing a biological neural network of a human subject. Such slowed visual representation(s) allows the deconstructed elements of the speech sound unit to be exercised in detail which makes an accurate and efficient establishing of the neural network possible.
[0052] Such biological neural network may comprise different cell types, such as neurons with a memory function storing the sound of a word or those which control the movement of muscles, in particular of the jaw, the lips, the tongue and/or the breathing muscles. The establishing of said neural network leads to a learning effect such that the human subject may show improved articulation, has learned the pronunciation of a foreign language or accent, or to the treatment of a speech disorder or a speech impairment. Thereby, the subject gets a visual and acoustic input in a pattern which triggers the establishing or reprogramming of the biological neural network and physically changing the connections between the cells.
[0053] Preferably, the subject is repeatedly exposed to simultaneous visual, acoustic and kinesthetic stimuli. Kinesthetically means here, the subject is performing the movement according to guidance or instructions as provided by the system to the subject, e.g. through a user interface, as described further below. The guidance or instructions are in the form of audio, visual instructions such as spoken or written instructions. The respective extended time intervals decrease over time, i.e., the subject is exposed to respective visual representations and acoustic reproductions and kinesthetic representations (while performing the movements) as outlined below at increased speed. Said visual representations may e.g. be provided by means of pictures, sketches, video, computer animations or a computer program as disclosed herein. Much preferred are animations, e.g. via video or computer animations. In embodiments, the analyzer is configured to determine the at least one articulatory parameter deviation as described hereinabove and a subject guidance unit is adaptive to the at least one articulatory parameter deviation so as to provide relevant subject feedback in the guidance. Thus, the guidance provided through the subject guidance unit is focused on one or more defects in the patient speech as identified by the analyzer (e.g. one or more areas of deviations between the subject speech and the standard speech that are embodied in exercise specific guidance to the subject for correcting the one or more areas of deviations). If the tongue movement is deviated from the standard one
[0054] In preferred embodiments, said the computer implemented system will further guide the steps(s) of:
(i) the subject performing the tongue movement for the predefined tongue time interval; (ii) the subject performing the lip and jaw movement for the predefined lip time interval; and/or (iii) the subject performing the airstream generation for the predefined airstream time interval.
[0058] Such performance step(s) increase the speed of the establishing the neural network. Preferably, all three steps (i) to (iii) are performed by the subject simultaneously. The method steps (i) to (iii) may be performed with or without producing a sound with the vocal cords. Thus, in some embodiments, any of the method steps (i) to (iii) are performed without producing a sound with the vocal cords. In some embodiments, any of the method steps (i) to (iii) are performed while producing a sound with the vocal cords. Typically, such performance steps are repeatedly done. The number or repetitions may vary. In some embodiments, additional steps of repetition for any of the method steps (i) to (iii) alone are included, as the subject may have particular difficulties with any of these steps (i) to (iii). The computer implemented system will optimize the number of repetitions and pace depending on the performance of the subject.
[0059] In the computer implemented method and system disclosed herein, i.e. the system for improving a human subject's articulation and establishing a biological neural network of a human subject with speech disorder.
[0060] In some embodiments, a motion capture device is used to record the subject's movements when performing the method steps, e.g. via video recording. This may be advantageous for destructing the speech sound unit and identifying a severity of an articulation defect or speech disorder.
[0061] In this system, a computer program product is provided, having program code causing a computer to implement any one of the methods disclosed herein when being executed.
[0062] In one embodiment, a speech sound produced by a human subject is analyzed by a software and deconstructed into the lip and jaw movement, the tongue movement and/or the airstream generation. This typically involves a signal input, e.g. via video recording for the movements and/or a special recorder of the generated vibration for the airstream.
[0063] In some embodiments, the software compares the movement of the lips and jaw of the subject to a predefined standard movement. Such predefined standard movement may e.g. be generated by analyzing data from one or more subjects producing correct speech sound units, such as a native speaker of a language. Depending on the subjects shape and size of the lips and jaw, there will be different standard lips and jaw movements. The software will choose one predefined standard lip and jaw movement tailed to the subjects shape and size of the jaw and lips. Subsequently, the software generates a signal and sends visual representations of the predefined lip and jaw movement to subject and/or auditory instructions. The subject may then correct the movement of the lip and jaw to match the predefined standard movement.
[0064] In some embodiments, the software compares the airstream generation of the subject to a predefined standard airstream generation. As above, such predefined standard airstream generation may e.g. be generated by analyzing data from one or more subjects producing correct speech sound units, such as a native speaker of a foreign language. Subsequently, the software generates a signal and sends visual representations of the predefined tongue movement to subject and/or auditory instructions. The subject may then correct the airstream generation to match the predefined standard airstream generation.
[0065] In some embodiments, the software compares the speech sound unit produced by the subject to the target speech sound unit. Such predefined target speech sound unit may e.g. be generated by analyzing speech sounds from one or more subjects producing correct speech sound units, such as a native speaker of a foreign language. Said comparison gives guidance on the subject's movement of the tongue. Stored on a database are predefined standard tongue movements and the sounds related to them. The software will determine which tongue movement the subject has performed and choose one predefined standard tongue movement for the subject. Subsequently, the software generates a signal and sends visual representations of the predefined tongue movement to subject and/or auditory instructions. The subject may then correct the movement of the tongue to match the predefined standard tongue movement. The described steps of analyzing, comparison and generating a signal can be applied to all different intervals explained of the method steps described herein.
[0066] FIG. 1 provides a schematic illustration of a system for training a subject's articulation. The system includes a video recorder 12 , an audio recorder 14 , a data receiver 10 , a database 20 , an analyzer 32 , a display generator 22 and a display 24 . The audio recorder 12 is configured to capture speech of a subject and to generate corresponding audio data 16 . The video recorder 14 is configured to capture video of articulatory motions of a subject, including lip, tongue and/or airway motions, and to generate corresponding video data 18 . Although a video recorder 14 is described herein, it is possible that other articulatory motion data 18 could be utilized, such as that generated by an articulatory motion sensor of some kind.
[0067] The data receiver 10 is configured to receive the audio and video data 16 , 18 and to pre-process the audio and video data 16 , 18 to produce pre-processed audio data 30 and pre-processed video data 40 . Pre-processing may include various filtering and compression operations.
[0068] The database 20 of the system stores therein standard speech audio and video data 26 , 28 that represent model speech of a subject without speech issues. The standard speech audio and video data 26 , 28 serves as a reference for comparison with the audio and video data 36 , 40 of the subject.
[0069] An analyzer 32 is configured to receive standard audio and video data 26 , 28 and the pre-processed audio and video data 30 , 40 of the subject. The analyzer 32 generally includes a comparison engine (not shown) for comparing the standard and subject audio and video data 26 , 28 , 30 , 40 to determine at least one articulatory parameter deviation between the standard speech audio data and video data 26 , 28 and the subject speech audio and video data 30 , 40 . The comparison engine, in embodiments, is configured to use image processing techniques to compare video files and audio processing techniques for comparing audio files. In some embodiments, the image processing techniques include image processing, such as segmentation and comparison, to extract relevant articulatory parameters from the video data 28 , 40 such as lip movement parameters, tongue movement parameters and airway parameters as described hereinbefore. The comparison engine is configured to use a trained neural network for comparing the standard and subject audio and video data 26 , 28 , 30 , 40 , in accordance with various embodiments. The analyzer 32 is configured to output a play speed parameter 34 based on the at least one articulatory parameter deviation as described further below. WO 2015030471 A1 discloses an exemplary analysis technique that could be used by the analyzer 32 of the present application. This document is hereby incorporated by reference.
[0070] The display generator 22 of the system is configured to receive at least the standard audio and video data 26 , 28 from the database 20 and to adapt a playback speed thereof based on the at least one articulatory parameter deviation. The at least one articulatory parameter deviation is configured so that the greater the deviation between the subject audio and video data 30 , 40 and the standard audio and video data 26 , 28 , the slower the playback of the standard audio and video data 26 , 28 according to the adaptations made by the display generator 22 . The display generator 22 is, in some embodiments, configured to receive the subject audio and video data 30 , 40 and to adapt playback thereof in order to synchronize with playback speed of the standard audio and video data 26 , 28 . In embodiments, the display generator 22 is configured to generate a play of the standard and subject audio and video data 26 , 28 , 30 , 40 together so that the subject can view the two plays at the same time. For example, a side by side playback is envisaged. The display generator 22 is configured to output rendered audio and video data 42 for output by the display and speakers 42 .
[0071] Although the system of FIG. 1 has been described in terms of processing both audio and video data, it is envisaging that just one of these data types could be used to provide useful training for the subject.
[0072] While there are shown and described presently preferred embodiments of the invention, it is to be understood that the invention is not limited thereto but may be otherwise variously embodied and practiced within the scope of the following claims. Since numerous modifications and alternative embodiments of the present invention will be readily apparent to those skilled in the art, this description is to be construed as illustrative only and is for the purpose of teaching those skilled in the art the best mode for carrying out the present invention. Accordingly, all suitable modifications and equivalents may be considered to fall within the scope of the following claims. | A computer implemented method and system is for training a subject's articulation. The system will receive, access and analyze the speech audio and video data of the subject. The data will be compared to standard speech audio and video data to calculate the deviation of the articulatory parameters between the recorded data of the subject and the standard data. The system will then deconstruct the speech unit and separately play the standard tongue movements, lip movements, jaw movements, and airstream generation. The system will then enable a gradual time converging of the initial separately played standard tongue movements, jaw movements, lip movements and airstream generation in response to a magnitude of the at least articulatory parameter deviation decreasing. Similarly, the system will adapt the display speed and the number of repetitions of these movements to optimize the articulation training. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a CMOS output stage, particularly adapted for use in analog circuits, audio devices, and for general application to any kind of operational amplifier.
2. Discussion of the Related Art
Analog circuits using MOS transistors suffer a drawback related to P-channel MOS transistors, whose threshold voltage drifts over time (changes value). This drift effect is caused by hot electrons trapped in the gate oxide and is particularly evident for transistors operating at high current densities and high voltages, such as power transistors used in operational amplifiers.
CMOS output stages are known wherein a MOS transistor in a diode configuration is employed as a reference for the gate voltage to be applied to the power MOS transistor when quiescent (i.e., when there is no output signal). The reference does not drift, because the current density flowing through the MOS transistor and the voltage across it are both low. However, the threshold of the power MOS transistor, which has to withstand intense currents and high voltages, drifts and thus causes undesirable variations in the quiescent current.
FIG. 1, which illustrates a conventional CMOS output stage, shows that a diode-connected MOS transistor and a reference current source are used for each power MOS transistor in order to set its quiescent current.
In particular, for the P-channel power MOS transistor 10, a diode-connected P-channel reference MOS transistor 12 is provided with a corresponding reference current source 14, and a differential stage 16 including two P-channel MOS transistors and two N-channel MOS transistors. Likewise, circuit elements that are mirror-symmetrical to those described above namely reference N-channel MOS transistor 20 and reference current source 22, are used for the N-channel power MOS transistor 18.
In the quiescent state, the voltage across the gate and source of the reference transistor 12 is reproduced across the gate and source of the power transistor 10 (the same occurs for reference transistor 20 and the power transistor 18). Therefore, in the quiescent state the current delivered by the power transistor is equal to the ratio of the channel geometries of the power transistor and of the reference transistor, multiplied by the value of the reference current set by the reference current source; assuming their threshold voltages are equal, the reference transistor and the power transistor are in a current mirror configuration.
The total quiescent current is the sum of the quiescent current conducted by the drain terminal of the P-channel power transistor 10 and of the current conducted by the N-channel power transistor 18 (which is not affected by threshold drift).
The above-described output stage suffers a first drawback: the quiescent current depends on the threshold voltage of the P-channel power transistor 10, which tends to vary over time (tends to decrease), whereas the threshold voltage of the P-type reference transistor 12 remains substantially constant over time. This decrease in the threshold voltage of the power transistor 10 results in an increase in the current delivered for the same gate voltage, which is unacceptable for some applications.
Further drawbacks include a considerable circuit area and a complicated circuit structure.
SUMMARY OF THE INVENTION
An object of the present invention is therefore to provide a CMOS output stage that is free from threshold drift of the P-channel power transistor of the stage and is accordingly capable of keeping the quiescent current stable.
Another object of the present invention is to provide a CMOS output stage having a smaller area occupation than conventional solutions.
Another object of the present invention is to provide a CMOS output stage that does not have a feedback loop.
Another object of the present invention is to provide a CMOS output stage that, when used in audio amplifiers, is capable of eliminating the noise that is normally generated when an amplifier is switched on.
Another object of the present invention is to provide a CMOS output stage that can be used as a gain and output stage of operational amplifiers.
Another object of the present invention is to provide a CMOS output stage having a wide frequency response.
Another object of the present invention is to provide a CMOS output stage that is highly reliable, relatively easy to manufacture and inexpensive.
According to the present invention, these and other objects are achieved by a CMOS output stage, comprising a complimentary transistor pair including a first MOS power transistor and a second MOS power transistor each having a drain terminal. The pair is connected between a power supply line and a ground, and an output of the stage is formed at the drain terminals of the first and second transistors. The output stage also includes a circuit for setting a quiescent current of the output stage including a reference current source connected to a current mirror and to a gate terminal of the first power MOS transistor, and an additional MOS transistor that is connected between the current mirror and the ground with a resistor interposed. The quiescent current is set by a channel geometry ratio of the second power MOS transistor and of a transistor included in the reference current source, multiplied by the reference current of the reference current source, the second power transistor being of the N-channel type.
BRIEF DESCRIPTION OF THE DRAWINGS
Further characteristics and advantages of the present invention will become apparent hereinafter from the following detailed description of a preferred but not exclusive embodiment of the CMOS output stage according to the invention, illustrated by way of non-limiting example in the accompanying drawings, wherein:
FIG. 1 circuit diagram of a conventional CMOS output stage;
FIG. 2 is a circuit diagram of a CMOS output stage according to the present invention; and
FIG. 3 is a Bode diagram of the open-loop gain of an operational amplifier whose gain stage and output stage include the circuit shown in FIG. 2.
DETAILED DESCRIPTION
With reference to FIG. 2, a CMOS output stage according to a preferred embodiment of the present invention comprises a first P-channel power transistor 1 and a second N-channel power transistor 2 that are connected in a CMOS configuration.
In the first transistor 1, the source terminal is connected to the supply voltage V DD and the drain terminal is connected to the drain terminal of the second transistor 2. The source terminal of the second transistor 2 is connected to the ground. The output of the stage, designated by OUT, is acquired at the drain terminals of the two transistors 1 and 2.
The gate terminal of the first transistor 1 is connected to the drain terminal of a third P-channel MOS transistor 3, the source terminal of which is connected to the supply voltage V DD . The drain terminal of the third transistor 3 is connected to a reference source 4 which is in turn connected to the ground.
In a diode-connected P-channel reference MOS transistor 5, the gate terminal is connected to the gate terminal of the MOS transistor 3, the source terminal is connected to the supply voltage V DD , and the drain terminal is connected to the drain terminal of an additional N-channel MOS transistor 6. The gate terminal of transistor 6 serves as an input to the CMOS output stage, and may be connected, for example, to the input stage of an operational amplifier (not shown). The source terminal of transistor 6 is connected to the ground by an interposed resistor R. The MOS transistors 5 and 6 are therefore connected to each other in a CMOS configuration.
The gate terminal of the transistor 2 is connected to the source terminal of the transistor 6. A compensating capacitor C is interposed between the gate terminal of the transistor 6 and the drain terminals of the MOS transistors 1 and 2.
With reference to FIG. 2, the operation of the CMOS output stage according to the present invention is as follows.
In the quiescent state, i.e., in the absence of an output signal, the current of the reference source 4 is equal to the current delivered by the drain terminal of the transistor 3. Transistors 3 and 5 form a current mirror and are assumed to be identical; thus, the current that flows through the transistor 5 is equal to the drain current of transistor 3.
Accordingly, when appropriately biased, the same current Iref (i.e. Vgs/R) also flows through transistor 6 and through the resistor R. As a result, a voltage that is equal to the reference voltage Vgs appears across the gate and source of power transistor 2.
The reference source 4 includes an N-channel MOS reference transistor 38 that has a gate-source voltage Vgs when biased by a reference current Iref 34. Accordingly, when the gate voltage of the power transistor 2 is equal to Vgs, the power transistor 2 mirrors the reference transistor 32 that is included in the reference source 4, assuming that their threshold voltages are substantially the same.
The quiescent current is therefore set by means of the channel geometry ratio of N-channel transistors; it is determined by the channel geometry ratio of the power transistor 2 and of the reference transistor 32, multiplied by the reference current Iref 34 that biases the reference transistor 32. In this manner, the quiescent current is related to the N-channel MOS power transistor 2, and the threshold voltage of the P-channel power transistor 1 does not appear in the expression of the quiescent current. Therefore, the quiescent current is not influenced by any drift of the P-channel transistor threshold voltage.
Considering transient-mode operation, and assuming that the transistor 1 is to more heavily conduct current, i.e., that a positive half-wave occurs (low signal input to the transistor 6), the gate voltage of the transistor 6 decreases and therefore the current through this transistor decreases.
Accordingly, the current conducted by the MOS transistors 3 and 5 decreases and in particular the current conducted by the transistor 3 is lower than the current conducted by the reference source 4. Therefore, the voltage of the gate terminal of the transistor 1 decreases and the current conducted by it increases.
By decreasing the gate voltage of the transistor 6 as mentioned, the voltage of its source terminal also decreases. As a result, the gate source voltage of the power transistor 2 decreases, as does the current it conducts to ground.
When instead the transistor 2 is to more heavily conduct current, i.e., when a negative half-wave occurs, the gate voltage of the transistor 6 increases, more current flows through transistor 6, and its source voltage increases accordingly. As a result, the gate voltage of the transistor 2 also increases and the transistor thus conducts a higher current.
At the same time, since the current flowing through the transistor 6 increases, the current conducted by the transistors 5 and 3 also increases. The transistor 3 therefore conducts a higher current than that of the reference source 4. As a result, the gate voltage of the power transistor 1 increases, and the transistor 1 conducts less or, in the extreme, switches off.
The chart shown in FIG. 3 plots the open-loop Bode diagram of an operational amplifier in which the gain and output stage is provided according to the preferred embodiment of the present invention.
The curve of the chart designated by the reference numeral 9 represents the amplitude, while the curve designated by the reference numeral 11 represents the phase. FIG. 3 shows that the frequency response has a wide band that reaches up to approximately 10 MHz.
In practice, it has been observed that the CMOS output stage according to the present invention fully achieves the intended objects, since it eliminates the threshold drift of the power transistors of the stage, thereby eliminating quiescent current variations. Additionally, the small number of circuit components of the solution according to the present invention allows a reduction of the physical area occupied by the CMOS output stage.
Having thus described at least one illustrative embodiment of the invention, various alterations, modifications and improvements will readily occur to those skilled in the art. Such alterations, modifications and improvements are intended to be within the scope and spirit of the invention. Accordingly, the foregoing description is by way of example only, and it is not intended as limiting. The invention's limit is defined only in the following claims and the equivalent thereto. | A CMOS output stage for providing stable quiescent current. The output stage includes a circuit that relates the quiescent current to the channel geometry of a power NMOS transistor and of an NMOS reference transistor of a reference current source. This configuration removes the dependency of the quiescent current on a power PMOS transistor used in the CMOS output stage, the threshold voltage of which may drift over time under high current and voltage operation, and adversely affects quiescent current stability. | 7 |
FIELD OF THE INVENTION
This invention relates to a method for hydrodesulfurizing naphtha. More particularly, a Co/Mo metal hydrogenation component is loaded on a silica or modified silica support in the presence of an organic additive and then sulfided to produce a catalyst which is used for hydrodesulfurizing naphtha.
BACKGROUND OF THE INVENTION
Environmental regulations mandate the lowering of sulfur levels in motor gasoline (mogas). For example, it is expected that regulations will require mogas sulfur levels of 30 ppm or less by 2006. In many cases, these sulfur levels will be achieved by hydrotreating naphtha produced from Fluid Catalytic Cracking (FCC cat naphtha), which is the largest contributor to sulfur in the mogas pool. Since sulfur in mogas can also lead to decreased performance of catalytic converters, a 30 ppm sulfur target is desirable even in cases where regulations would permit a higher level. As a result, techniques are required that reduce the sulfur in cat naphthas while at the same time minimizing the reduction of beneficial properties such as octane number.
Conventional fixed bed hydrotreating can reduce the sulfur level of cracked naphthas to very low levels. However, such hydrotreating also results in significant octane number loss due to extensive reduction of the olefin content in the naphtha as well as excessive consumption of hydrogen during the hydrotreating process. Selective hydrotreating processes have recently been developed to avoid such olefin saturation and octane number loss. Unfortunately, the H 2 S liberated in the process reacts with retained olefins forming mercaptan sulfur by reversion. Such processes can be conducted at severities which produce product within sulfur regulations. However, significant octane number loss also occurs.
One proposed approach for preserving octane number during sulfur removal is to modify the olefin content of the feed using an olefin-modification catalyst followed by contact with a hydrodesulfurization (HDS) catalyst (U.S. Pat. No. 6,602,405). The olefin modification catalyst oligomerizes the olefins.
One recently developed method of HDS is SCANfining, which is a process developed by Exxon Mobil Corporation. SCANfining is described in National Petroleum Refiners Association paper # AM-99-31 titled “Selective Cat Naphtha Hydrofining with Minimal Octane Loss” and U.S. Pat. Nos. 5,985,136 and 6,013,598. Generally, SCANfining is a process that includes one and two-stage processes for hydrodesulfurizing a naphtha feedstock, where the feedstock is contacted with a hydrodesulfurization catalyst comprised of about 1 wt. % to about 10 wt. % MoO 3 ; and about 0.1 wt. % to about 5 wt. % CoO; and a Co/Mo atomic ratio of about 0.1 to about 1.0; and a median pore diameter of about 60 Å to about 200 Å.
Even though SCANfining controls the degree of olefin saturation while achieving a high degree of desulfurization, there is still a need to improve the selectivity of the catalyst system to further reduce the degree of olefin saturation thereby further minimizing octane number loss.
SUMMARY OF THE INVENTION
This invention relates to a method for making a catalyst and a method for the hydrodesulfurization (HDS) of naphtha. One embodiment relates to a method for making a catalyst suitable for the HDS of naphtha comprising: (i) impregnating a silica support that has a silica content of at least about 85 wt. %, based on silica with an aqueous solution of (a) a cobalt salt, (b) a molybdenum salt, and (c) at least one organic additive to form a catalyst precursor; (ii) drying the catalyst precursor at temperatures less than about 200° C. to form a dried catalyst precursor; and (iii) sulfiding the dried catalyst precursor to form the catalyst, provided that the dried catalyst precursor or catalyst is not calcined prior to sulfiding or use for HDS.
Another embodiment relates to a method for the HDS of naphtha having an olefin content of at least about 5 wt. %, based on naphtha comprising: (i) contacting the naphtha with a selective HDS catalyst under hydrodesulfurization conditions, wherein the selective HDS catalyst is prepared by impregnating a silica support that has a silica content of at least about 85 wt. %, based on silica with an aqueous solution of (a) a cobalt salt, (b) a molybdenum salt, and (c) at least one organic additive to form a catalyst precursor; (ii) drying the catalyst precursor at temperatures less than about 200° C. to form a dried catalyst precursor; and (iii) sulfiding the dried catalyst precursor to form the catalyst, provided that the dried catalyst precursor or catalyst is not calcined prior to sulfiding or use for HDS.
The silica supported catalyst when used for the HDS of a naphtha shows improved selectivity towards olefin saturation while maintaining a high level of HDS of the naphtha feed.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 is a graph showing the HDS performance of CoMo/silica catalysts with NTA as organic additive.
FIG. 2 is a graph showing a plot of % C 5 olefin saturation vs. % HDS of 2-methyl-thiophene.
FIG. 3 is a graph showing % C 5 olefin saturation vs. % 2-methyl-thiophene HDS.
FIG. 4 is a graph showing % C 5 olefin saturation vs. % 2-methyl-thiophene HDS.
DETAILED DESCRIPTION OF THE INVENTION
The term “naphtha” refers to the middle boiling range hydrocarbon fraction or fractions that are major components of gasoline, while the term “FCC naphtha” refers to a preferred naphtha that has been produced by the well known process of fluid catalytic cracking. Naphthas having a middle boiling range are those have boiling points from about 10° C. (i.e., from about C 5 ) to about 232° C. at atmospheric pressure, preferably from about 21° C. to about 221° C. Naphtha produced in an FCC process without added hydrogen contains a relatively high concentration of olefins and aromatics. Other naphthas such as steam cracked naphtha and coker naphtha may also contain relatively high concentrations of olefins. Typical olefinic naphthas have olefin contents from about 5 wt. % to about 60 wt. %, based on the weight of the naphtha, preferably 5 wt. % to about 40 wt. %; sulfur contents from about 300 ppmw to about 7000 ppmw, based on the weight of the naphtha; and nitrogen contents from about 5 ppmw to about 500 ppmw, based on the weight of the naphtha. Olefins include open chain olefins, cyclic olefins, dienes and cyclic hydrocarbons with olefinic side chains. Because olefins and aromatics are high octane number components, olefinic naphtha generally exhibits higher research and motor octane values than does hydrocracked naphtha. While olefinic naphthas are typically high in olefin content, they may also contain other compounds, especially sulfur-containing and nitrogen-containing compounds.
Selective Catalyst
In one embodiment, the catalyst for the selective removal of sulfur with minimal olefin saturation from an olefinic naphtha is a silica supported catalyst that has been impregnated with (a) a cobalt salt, (b) a molybdenum salt and (c) at least one organic additive, such as organic ligands. The silica support contains at least about 85 wt. % silica, based on silica support, preferably at least about 90 wt. % silica, especially at least about 95 wt. % silica. Examples of silica supports include silica, MCM-41, silica-bonded MCM-41, fumed silica, metal oxide modified siliceous supports and diatomaceous earth.
The cobalt and molybdenum salts used to impregnate the silica support may be any water-soluble salt. Preferred salts include carbonates, nitrates, heptamolybdate and the like. The amount of salt is such that the silica support will contain from about 2 wt. % to about 8 wt. % cobalt oxide, based on the weight of the catalyst, preferably from about 3 wt. % to about 6 wt. %, and from about 8 wt. % to about 30 wt. % molybdenum oxide, preferably about 10 wt. % to 25 about 25 wt. %, based on the weight of the support.
The silica support may also be doped with metals from Groups 2-4 of the Periodic Table based on the IUPAC format having Groups 1-18, preferably from Groups 2 and 4. Examples of such metals include Zr, Mg, Ti. See, e.g., The Merck Index, Twelfth Edition, Merck & Co., Inc., 1996.
Organic ligands are organic additives that are hypothesized to aid in distributing the Co and Mo components on the silica support. The organic ligands contain oxygen and/or nitrogen atoms and include mono-dentate, bi-dentate and poly-dentate ligands. The organic ligands may also be chelating agents. Organic ligands include at least one of carboxylic acids, polyols, amino acids, amines, amino alcohols, ketones, esters and the like. Examples of organic ligands include phenanthroline, quinolinol, salicylic acid, acetic acid, ethylenediaminetetraacetic acid (EDTA), cyclohexanediaminetetraacetic acid (CYDTA), alanine, arginine, triethanolamine (TEA), glycerol, histidine, acetylacetonate, guanidine, and nitrilotriacetic acid (NTA), citric acid and urea.
While not wishing to be bound to any particular theory, it is postulated that the organic ligands such as arginine, citric acid and urea form complexes with at least one of Co and Mo. These Co- and/or Mo-organic ligand complexes interact with the silica surface to disperse the metals more evenly across the silica surface. This may lead to improved selectivity toward olefin saturation while maintaining the HDS activity for desulfurizing the naphtha feed.
Catalyst Preparation and Use
Silica supports were impregnated with aqueous solutions of Co and Mo salts using conventional techniques. The organic ligand may be added to the aqueous solution of salts prior to contact with the silica support. One embodiment for impregnating the silica support with metal salt is by the incipient wetness method. Incipient wetness is a conventional method, i.e., one known to those skilled in the art of hydroprocessing catalyst preparation, manufacture, and use. In this method, an aqueous solution containing metal salts and organic additive is mixed with the support up to the point of incipient wetness using conventional techniques.
The manner of impregnation of the silica support by metal salt may be by impregnating the silica support with a mixture of a cobalt salt and organic ligand using incipient wetness, drying the impregnated support and then impregnating the dried support with a molybdenum salt solution or molybdenum salt solution contain organic ligand up to the point of incipient wetness. In another embodiment, the order of impregnation by cobalt salt followed by molybdenum salt may be reversed. In yet another embodiment, the support may be co-impregnated with a mixture of cobalt salt and molybdenum salt plus organic ligand to incipient wetness. The co-impregnated support may be dried and the co-impregnation process repeated. In yet another embodiment, an extruded silica support may be impregnated with a mixture of cobalt salt, molybdenum salt and organic ligand and the impregnated support dried. This treatment may be repeated if desired. In all the above embodiments, the organic ligand may be a single ligand or may be a mixture of ligands. The impregnated silica support isolated from the reaction mixture is heated and dried at temperatures in the range from about 50° C. to about 200° C. to form a catalyst precursor. The drying may be under vacuum, or in air, or inert gas such as nitrogen.
The dried catalyst precursor is treated with hydrogen sulfide at concentrations of from about 0.1 vol. % to about 10 vol. % based on total volume of gases present, for a period of time and at a temperature sufficient to convert metal oxide, metal salt or metal complex to the corresponding sulfide in order to form the HDS catalyst. The hydrogen sulfide may be generated by a sulfiding agent incorporated in or on the catalyst precursor. In an embodiment, the sulfiding agent is combined with a diluent. For example, dimethyl disulfide can be combined with a naphtha diluent. Lesser amounts of hydrogen sulfide may be used but this may extend the time required for activation. An inert carrier may be present and activation may take place in either the liquid or gas phase. Examples of inert carriers include nitrogen and light hydrocarbons such as methane. When present, the inert gases are included as part of the total gas volume. Temperatures are in the range from about 150° C. to about 700° C., preferably about 160° C. to about 343° C. The temperature may be held constant or may be ramped up by starting at a lower temperature and increasing the temperature during activation. Total pressure is in the range up to about 5000 psig (34576 kPa), preferably about 0 psig to about 5000 psig (101 to 34576 kPa), more preferably about 50 psig to about 2500 psig (446 to 17338 kPa). If a liquid carrier is present, the liquid hourly space velocity (LHSV) is from about 0.1 hr −1 to about 12 hr −1 , preferably about 0.1 hr −1 to about 5 hr −1 . The LHSV pertains to continuous mode. However, activation may also be done in batch mode. Total gas rates may be from about 89 m 3 /m 3 to about 890 m 3 /m 3 (500 to 5000 scf/B).
Catalyst sulfiding may occur either in-situ or ex-situ. Sulfiding may occur by contacting the catalyst with a sulfiding agent, and can take place with either a liquid or gas phase sulfiding agent. Alternatively, the catalyst may be presulfurized such that H 2 S may be generated during sulfiding. In a liquid phase sulfiding agent, the catalyst to be sulfided is contacted with a carrier liquid containing sulfiding agent. The sulfiding agent may be added to the carrier liquid or the carrier liquid itself may be sulfiding agent. The carrier liquid is preferably a virgin hydrocarbon stream and may be the feedstock to be contacted with the hydroprocessing catalyst but may be any hydrocarbon stream such as a distillate derived from mineral (petroleum) or synthetic sources. If a sulfiding agent is added to the carrier liquid, the sulfiding agent itself may be a gas or liquid capable of generating hydrogen sulfide under activation conditions. Examples include hydrogen sulfide, carbonyl sulfide, carbon disulfide, sulfides such as dimethyl sulfide, disulfides such as dimethyl disulfide, and polysulfides such as di-t-nonylpolysulfide. The sulfides present in certain feeds, e.g., petroleum feeds, may act as sulfiding agent and include a wide variety of sulfur-containing species capable of generating hydrogen sulfide, including aliphatic, aromatic and heterocyclic compounds.
The dried catalyst is not calcined prior to either sulfiding or use for HDS. Not calcining means that the dried catalyst is not heated to temperatures above about 300° C., preferably about 200° C. By not calcining the catalyst, from about 60 wt. % to about 100 wt. % of the dispersing aid remains on the catalyst prior to sulfiding or use for HDS, based on the weight of the catalyst.
Following sulfiding, the catalyst may be contacted with naphtha under hydrodesulfurizing conditions. Hydrodesulfurizing conditions include temperatures of from about 150° C. to about 400° C., pressures of from about 445 kPa to about 13890 kPa (50 to 2000 psig), liquid hourly space velocities of from about 0.1 to 12, and H 2 treat gas rates of from about 89 m 3 /m 3 to 890 about m 3 /m 3 (500 to 5000 scf/B). After hydrodesulfurization, the desulfurized naphtha can be conducted away for storage or for further processing, such as stripping to remove hydrogen sulfide. The desulfurized naphtha is useful for blending with other naphtha boiling-range hydrocarbons to make mogas.
Embodiments, including preferred embodiments, are illustrated in the following examples.
EXAMPLE 1
Catalyst Preparation
The catalyst was prepared by an incipient wetness technique. Davisil silica, fumed silica Cab-O-Sil, MCM-41, Y/SiO 2 , Mg/SiO 2 , Ti/SiO 2 and Zr/SiO 2 were prepared as supports. The Co and Mo precursor compounds used in the preparation were cobalt carbonate hydrate and ammonium heptamolybdate tetrahydrate. The organic additive nitrilotriacetic acid (NTA) was used in the impregnation solution. The mole ratio of NTA to cobalt carbonate hydrate was 0.5.
The mixture solution containing NTA, Co and Mo was prepared as following: appropriate amounts of NTA and cobalt carbonate were added in distilled H 2 O and the mixture solution was stirred until the solution became clear. Then, appropriate amount of ammonium heptamolybdate tetrahydrate was added to make the final solution. After impregnation, the catalyst was dried at 160° F. under vacuum overnight (˜14 hr). The catalysts contained 6% CoO and 24% MoO 3 metal loading. Besides NTA, organic additives of phenanthroline, quinolinol, salicylic acid, acetic acid, ethylenediaminetetraacetic acid (EDTA), cyclohexanediaminetetraacetic acid (CYDTA), alanine, arginine, triethanolamine (TEA), glycerol, histidine, acetylacetonate and guanidine were also used in the catalyst preparation.
FIG. 1 is a graph showing the HDS performance of CoMo/silica catalysts with NTA as organic additive. From FIG. 1 , it can be seen that the selectivity of CoMo supported on MCM-41 with NTA as organic additive without calcination has ˜60% improvement vs. commercial catalyst (RT-225) manufactured by Albemarle at ˜60% HDS level. At around 87% HDS conversion, the selectivity improvement of CoMo/MCM-41 is 48% over RT-225. At about 97% HDS conversion, the selectivity improvement above RT-225 is about 40%. CoMo sulfides supported on Davisil silica and fumed silica also showed 40-60% selectivity improvements over RT-225.
Table 1 shows a selectivity comparison of CoMo/Silica-NTA with and without calcination.
TABLE 1
Thermal Treatment
Selectivity vs.
Support
Before Sulfiding
RT-225
Cab-O-Sil
High Temp Calcined
Same
Cab-O-Sil
160 F. Vacuum Dried
30-40% Better
Davisil Silica
High Temp Calcined
Same
Davis Silica
160 F. Vacuum Dried
40-60% Better
MCM-41
High Temp Calcined
Same
MCM-41
160 F. Vacuum Dried
40-60% Better
Table 1 shows the impact of calcination on the selectivity of the catalysts. Upon calcination at high temperature prior to catalyst sulfidation, the selectivity of CoMo on siliceous supports decreased to the level of the reference catalyst RT-225. NTA forms stable complexes with Co and Mo. It is thought that the CoMo-NTA complex helps CoMo disperse on the silica support through the interaction of hydroxyl groups of silica and the hydrophilic function groups of NTA. High temperature calcination decomposes the complexes, therefore damaging the NTA dispersion function and resulting in a catalyst with low selectivity.
EXAMPLE 2
RT-225, a commercial Co/Mo HDS catalyst manufactured by Albemarle Corporation and the supported CoMo catalysts according to the invention with NTA as dispersing aid were sulfided using virgin naphtha and 3% H 2 S. The respective catalysts were not calcined prior to use.
Feed for the catalyst evaluation was a C 5 -350° F. naphtha feed containing 1408 ppmw S and 46.3 wt. % olefins, based on the weight of the naphtha. The conditions for HDS evaluation of catalysts from Example 1 were 274° C., 220 psig, liquid hourly space velocity of from about 1 to about 12, and H 2 treat gas rate of from about 89 to about 890 m 3 /M 3 (500 to 5000 scf/B). The results of the HDS evaluation for the base case RT-225 catalyst, MCM-41 catalyst, Davisil silica catalyst and fumed silica Cab-O-Sil® are shown in FIG. 1 , which is a graph showing a plot of % C 5 olefin saturation vs. % HDS of 2-methyl-thiophene.
EXAMPLE 3
The selectivity of Davisil silica and the modified silica supports of Y/SiO 2 , Mg/SiO 2 , Ti/SiO 2 and Zr/SiO 2 , with NTA as organic ligand are demonstrated in this example using the preparative method of Example 1 and the HDS procedure of Example 2. FIG. 2 is a graph showing a plot of % C 5 olefin saturation on a weight basis vs. % HDS of 2-methyl-thiophene on a weight basis, based on the weight of the naphtha. As can be seen in FIG. 2 , the catalysts showed substantial selectivity improvements over the RT-225 commercial catalyst, with 40 to 60% less olefin saturation between 60 and 90% HDS.
EXAMPLE 4
This example shows the effect of organic ligands (additives) on a CoMo on Davisil silica catalyst prepared according to Example 1 on HDS performance using the procedure of Example 2. The organic ligands are glycerol, acetic acid, TEA, phenanthroline, quinolinol, acetylacetonate, salicylic acid and NTA. FIG. 3 is a graph showing % C 5 olefin saturation vs. % 2-methyl-thiophene HDS, on a weight basis. As shown in FIG. 3 , between 60 and 95% HDS conversions, all catalysts showed about 30 to about 60% selectivity improvements over the RT-225 commercial catalyst. Among the organic ligands used for catalyst preparations, the catalyst made with NTA showed better selectivity than other catalysts made with organic ligands, such as phenanthroline, quinolinol, salicylic acid, acetic acid, triethanolamine (TEA), glycerol and acetylacetonate. However, catalysts made with organic ligands showed better selectivity as compared to the base case, RT-225.
EXAMPLE 5
This example shows the effect of a different set of organic ligands on a CoMo on Davisil silica catalyst prepared according to Example 1 on HDS performance using the procedure of Example 2. The organic ligands are NTA, guanidine, ethylenediaminetetraacetic acid (EDTA), cyclohexanediaminetetraacetic acid (CYDTA), alanine and arginine and are compared to RT-225 as in Example 4 FIG. 4 is a graph showing % C5 olefin saturation vs. % 2-methyl-thiophene HDS, on a weight basis. As shown in FIG. 4 , the catalysts made with NTA and guanidine exhibit better selectivity than the catalysts made with other organic ligands but catalysts made with organic ligands showed better selectivity as compared to RT-225. | Naphtha is selectively hydrodesulfurized with retention of olefin content. More particularly, a CoMo metal hydrogenation component is loaded on a silica or modified silica support in the presence of an organic additive to produce a catalyst which is then used for hydrodesulfurizing naphtha while retaining olefins. | 2 |
FIELD OF THE INVENTION
This invention relates to novel tissue graft constructs and their use to promote regrowth and healing of damaged or diseased tissue structures. More particularly this invention is directed to use of intestinal tissue grafts as connective tissue substitutes, and most particularly to their use in surgical repair of ligaments and tendons and for their use as a surgically applied bone wrap to promote healing of bone fractures.
BACKGROUND AND SUMMARY OF THE INVENTION
Researchers in the surgical arts have been working for many years to develop new techniques and materials for use as grafts to replace or repair damaged or diseased tissue structures, particularly bones and connective tissues, such as ligaments and tendons, and to hasten fracture healing. It is very common today, for instance, for an orthopaedic surgeon to harvest a patellar tendon of autogenous or allogenous origin for use as a replacement for a torn cruciate ligament. The surgical methods for such techniques are well known. Further it has become common for surgeons to use implantable prostheses formed from plastic, metal and/or ceramic material for reconstruction or replacement of physiological structures. Yet despite their wide use, surgically implanted prostheses present many attendant risks to the patient. It will suffice to say that surgeons are in need of a non-immunogenic, high tensile strength graft material which can be used for surgical repair of bones, tendons, ligaments and other functional tissue structures.
Researchers have been attempting to develop satisfactory polymer or plastic materials to serve as ligament, or tendon replacements or as replacements for other connective tissues, such as those involved in hernias and joint-dislocation injuries. It has been found that it is difficult to provide a tough, durable plastic material which is suitable for long-term connective tissue replacement. Plastic materials can become infected and difficulties in treating such infections often lead to graft failure.
In accordance with the present invention there is provided tissue graft constructs for orthopaedic and other surgical applications which in experiments to date have been shown to exhibit many of the desirable characteristics important for optimal graft function.
The graft construct in accordance with this invention is prepared from a delaminated segment of intestinal tissue of a warm-blooded vertebrate, the segment comprising the tunica submucosa, the muscularis mucosa and the stratum compactum of the tunica mucosa. The tunica submucosa, muscularis mucosa and stratum compactum are delaminated from the tunica muscularis and the luminal portion of the tunica mucosa of the segment of intestinal tissue. The resulting segment is a tubular, very tough, fibrous, collagenous material which is fully described in U.S. Pat. No. 4,902,508 issued Feb. 20, 1990 and U.S. Pat. No. 4,956,178 issued Sep. 11, 1990, which patents are expressly incorporated herein by reference. In those patents, the tissue graft material is primarily described in connection with vascular graft applications.
Intestinal submucosa graft material may be harvested from a biological source such as animals raised for meat production, including, for example, pigs, cattle and sheep or other warm-blooded vertebrates. Older sows having a weight between 400 and 600 lbs. have been found to be particularly good sources of graft material for use for this invention. A graft segment removed from such an older sow can have a tensile strength of up to 1700 psi in the longitudinal direction of the intestine. Thus, there is a ready source of intestinal submucosa graft material in slaughter houses around the country, ready to be harvested and utilized in accordance with the present invention.
The tri-layer intestinal segments used to form the graft constructs in accordance with this invention can be used in their delaminate tubular form or they can be cut longitudinally or laterally to form elongated tissue segments. In either form, such segments have an intermediate portion and opposite end positions and opposite lateral portions which can be formed for surgical attachment to existing physiological structures, using surgically acceptable techniques.
An advantage of the intestinal submucosa graft formed for surgical repair in accordance with the present invention is its resistance to infection. The intestinal submucosa graft material, fully described in the aforesaid patents, have high infection resistance, long shelf life and storage characteristics. It has been found that xenogeneic intestinal submucosa is compatible with hosts following implantation as vascular grafts, ligaments and tendons because of its basic composition. The intestinal submucosa connective tissue is apparently very similar among species. It is not recognized by the host's immune system as "foreign" and therefore is not rejected. Further the intestinal submucosa grafts appear to be extremely resistant to infection because of their trophic properties toward vascularization and toward endogenous tissues surgically affixed or otherwise associated with the implant graft. In fact, most of the studies made with intestinal submucosa grafts to date have involved non-sterile grafts, and no infection problems have been encountered. Of course, appropriate sterilization techniques acceptable to the Federal Drug Administration (FDA) may well be used to treat grafts in accordance with the present invention.
It has been found that unsterilized clean intestinal submucosa graft material can be kept at 4° C. (refrigerated) for at least one month without loss of graft performance. When the intestinal submucosa graft material is sterilized by known methods, it will stay in good condition for at least two months at room temperature without any resultant loss in graft performance.
It has also been found that the grafts formed and used in accordance with this invention upon implantation undergo biological remodelling. They serve as a rapidly vascularized matrix for support and growth of new endogenous connective tissue. The graft material used in accordance with this invention has been found to be trophic for host tissues with which it is attached or otherwise associated in its implanted environment. In multiple experiments the graft material has been found to be remodelled (resorbed and replaced with autogenous differentiated tissue) to assume the characterizing features of the tissue(s) with which it is associated at the site of implantation. In tendon and ligament replacement studies the graft appears to develop a surface that is synovialized. Additionally, the boundaries between the graft and endogenous tissue are no longer discernible. Indeed, where a single graft "sees" multiple microenvironments as implanted, it is differentially remodeled along its length. Thus when used in cruciate ligament replacement experiments not only does the portion of the graft traversing the joint become vascularized and actually grow to look and function like the original ligament, but the portion of the graft in the femoral and tibial bone tunnels rapidly incorporates into and promotes development of the cortical and cancellous bone in those tunnels. In fact, it has been found that after six months, it is not possible to identify the tunnels radiographically. It appears that intestinal submucosa serves as a matrix for and stimulates bone regrowth (remodeling) within the tunnels. The bone tunnels with the encompassed intestinal submucosa graft have never been shown to be a weak point in the tensile-strength evaluations after sacrifice of test dogs accomplished to date.
It is one object of the present invention, therefore, to provide graft constructs for use as connective tissue substitute, particularly as a substitute for ligaments and tendons. The graft is formed from a segment of intestinal tissue of a warm-blooded vertebrate. The graft construct comprises the tunica submucosa, the muscularis mucosa and the stratum compactum of the tunica mucosa, said tunica submucosa, muscularis mucosa and stratum compactum being delaminated from the tunica muscularis and the luminal portions of the tunica mucosa of the segment of intestinal tissue. The graft construct has a longitudinal dimension corresponding to the length of the segment of intestinal tissue and a lateral dimension proportioned to the diameter of the segment of intestinal tissue. For tendon and ligament replacement, applications the resulting segment is typically preconditioned by stretching longitudinally to a length longer than the length of the intestinal tissue segment from which it was formed. For example, the segment is conditioned by suspending a weight from said segment, for a period of time sufficient to allow about 10 to about 20% elongation of the tissue segment. Optionally, the graft material can be preconditioned by stretching in the lateral dimension. (The graft material exhibits similar viscoelastic properties in the longitudinal and lateral dimensions). The graft segment is then formed in a variety of shapes and configurations, for example, to serve as a ligament or tendon replacement or substitute or a patch for a broken or severed tendon or ligament. Preferably, the segment is shaped and formed to have a layered or even a multilayered configuration with at least the opposite end portions and/or opposite lateral portions being formed to have multiple layers of the graft material to provide reinforcement for attachment to physiological structures, including bone, tendon, ligament, cartilage and muscle. In a ligament replacement application, opposite ends are attached to first and second bones, respectively, the bones typically being articulated as in the case of a knee joint. It is understood that ligaments serve as connective tissue for bones, i.e.. between articulated bones, while tendons serve as connective tissue to attach muscle to a bone.
When a segment of intestine is first harvested and delaminated as described above, it will be a tubular segment having an intermediate portion and opposite end portions. The end portions are then formed, manipulated or shaped to be attached, for example, to a bone structure in a manner that will reduce the possibility of graft tearing at the point of attachment. Preferably it can be folded or partially everted to provide multiple layers for gripping, for example, with spiked washers or staples. Alternatively, the segment may be folded back on itself to join the end portions to provide a first connective portion to be attached, for example, to a first bone and a bend in the intermediate portion to provide a second connective portion to be attached to a second bone articulated with respect to the first bone.
For example, one of the end portions may be adapted to be pulled through a tunnel in, for example, the femur and attached thereto, while the other of the end portions may be adapted to be pulled through a tunnel in the tibia and attached thereto to provide a substitute for the natural cruciate ligament, the segment being adapted to be placed under tension between the tunnels to provide a ligament function, i.e., a tensioning and positioning function provided by a normal ligament.
The intestinal submucosa segment, which in its preferred embodiment consists essentially of the tunica submucosa, muscularis mucosa and stratum compactum, has been found to have good mechanical strength characteristics in the same delaminated tubular form in which it is produced following the described delamination procedure. It has been found that having the stratum compactum layer inside the tubular form in a tendon or ligament graft provides good trophic properties for vascularization. It is believed that grafts used in accordance with the present invention with the intestinal segment inverted, i.e., with the stratum compactum on the outside will exhibit like functionality, but further testing is required to determine the vascularization characteristics with that structure utilized, for example, as a tendon or ligament graft.
Another object of the present invention is to provide a method for surgical repair of diseased or damaged tissues connecting first and second tissues structures selected from the group consisting of bone, ligament, tendon, cartilage and muscle. The method comprises the step of attaching the first and second structures to opposite end portions or opposite lateral portions of a tissue graft construct formed in accordance with the above described embodiments. The graft comprises the tunica submucosa, the muscularis mucosa and the stratum compactum of a segment of intestinal tissue of a warm-blooded vertebrate, said tunica submucosa, muscularis mucosa and stratum compactum being delaminated from the tunica muscularis and the luminal portion of the tunica mucosa of said intestinal tissue.
Because grafts used in orthopaedic applications are typically placed under tension in their surgical installation, it may be preferable to combine two or even more tissue segments to provide a multi-ply (multi-layered) graft construct. It is another object of the present invention, therefore, to provide such grafts in which two or more PG,11 intestinal segments are arranged to have their end portions joined together with the joined end portions and/or lateral portions adapted to be attached to a bone, tendon, ligament or other physiological structure. One method for providing a double intestinal segment may be to pull one tubular segment internally within another segment to provide a double-walled tube, the joined ends of which can be attached, for example, to a bone, tendon or ligament. These doubled segments will provide enhanced tensile strength and resistance to stretching under tension.
A further object of the present invention is to provide such a graft in which one of said end portions is adapted to be pulled through a tunnel in, for example, the femur and attached thereto and the other of said end portion is adapted to be pulled through a tunnel in the tibia and attached thereto to provide a substitute for the natural cruciate ligament, the segment being adapted to be placed under tension between the tunnels to provide a ligament function. Similar procedures can be employed to provide ligament function to other articulating bones.
Still a further object of the present invention is to provide an orthopaedic graft for use as connective tissue to hold fractured bone pieces together and in proper orientation in the body, the segment being formed to serve as a fracture wrap about segments of fractured bone and to be attached to the bone.
One other object of this invention is to provide a method for promoting the healing and/or regrowth of diseased or damaged tissue structures by surgically repairing such structures with a tissue graft construct prepared from a segment of intestinal submucosal tissue as described above. The implanted graft construct is trophic toward vascularization and differentiated tissue growth and is essentially remodelled to assume the structural and functional characteristics of the repaired structure.
Other objects and features of the present invention will become apparent as this description progresses.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a lateral view of a knee with a graft in accordance with the present invention extending through a tunnel through the tibia and wrapped over the top of a femur.
FIG. 2 shows an anterior view of the left stifle showing the graft arrangement of FIG. 1.
FIG. 3 shows an anterior view of the left stifle with a graft in accordance with the present invention extending through tunnels in both the tibia and the femur with the end portions of the graft attached by screws and spiked washers in accordance with standard orthopaedic surgery practices.
FIG. 4 shows a medial view of the left stifle showing a graft in accordance with the present invention used as a medial collateral ligament replacement with opposite end portions of the graft attached by sutures to existing connective tissues.
FIG. 5 is a fragmentary view showing an achilles tendon with a graft placement in accordance with the present invention adapted to join a break in the tendon.
FIG. 6 is a fragmentary perspective view showing the graft of FIG. 5 being attached.
FIG. 7 is a sectional view showing how the graft is wrapped twice about the tendon in FIGS. 5 and 6.
FIG. 8 shows a tubular section of the graft folded back on itself to provide a double thickness of intestinal submucosa segment.
FIG. 9 is a fragmentary perspective view showing a graft segment pulled within another graft segment to provide a double-walled or tube-within-a tube arrangement.
DETAILED DESCRIPTION OF THE INVENTION
The intestinal submucosa graft of the present invention is harvested and delaminated in accordance with the description in the prior U.S. Pat. Nos. 4,956,178 and 4,902,508. An intestinal submucosa segment is thereby obtained.
To date, of course, such grafts have been used only on test animals. The following description is based upon the experimental uses made or contemplated to date.
In FIGS. 1 and 2, a femur is shown above the tibia with a lateral view in FIG. 1 and an anterior view of the left stifle in FIG. 2. As best seen in FIG. 2, a graft 10 is installed through a bone tunnel 12 in the tibia in a fashion well-known in orthopaedic surgery. The end portion of the graft 10 is attached as indicated at 14 by a spiked washer and screw arrangement to provide the connection to the tibia. The other end portion of the graft 10 is pulled up through the space between the condylar portions and wrapped over the lateral femoral condyle to be attached as indicated at 16 by another spiked washer and screw arrangement. It will be appreciated that surgeons will generally 14, 16. place such grafts under tension between connections
The arrangement shown in FIGS. 1 and 2 may well be more adaptable for testing in dogs than it is for repair of human knees. Thus, FIG. 3 shows a likely human application of the graft 10 extending through aligned tunnels 20, 22 in the femur and tibia with the opposite ends of the graft 10 being connected by teflon spiked washers and screws as indicated at 14 and 16. Such screws and spiked washers may be replaced with spiked bone staples or any other type of soft-tissue-to-bone fixation devices commonly used in orthopaedic surgery. When the graft is pulled through the tunnels 20, 22 and placed under tension by the attachments indicated at 14, 16, the graft serves a ligament function between the femur and tibia. The graft also apparently stimulates bone growth in the tunnels such that the tunnels close in on the grafts to make connections which, after a period of time, do not have to be supplemented by the screw and washer arrangements.
FIG. 4 illustrates an intestinal submucosa graft 10 used as a medial collateral ligament replacement attached by sutures to existing adjacent tissues. Thus lateral edges 23,25 of the tubular graft 10 are sutured to the posterior oblique ligament 24 and the patellar tendon 26 while opposite ends 27,29 of graft 10 are sutured to ligament/tendon tissues associated with the femur and tibia, respectively. The graft 10 is preferably placed under moderate tension. As discussed above, the graft may comprise one or more intestinal segments layered together to provide additional strength.
FIGS. 5, 6 and 7 show how a segment of intestinal submucosa 30 may be shaped and formed to connect a broken or severed achilles tendon. The segment 30 is shown as an elongated sheet, its longest dimension corresponding to the longitudinal axis of the intestine from which the segment is removed. The graft segment has generally parallel sides 32, 34 and opposite ends 36, 38. This segment 30 is wrapped about the achilles tendon as shown in FIG. 7 to provide a double wrap or multilayered intermediate portion with the sides 32, 34 providing multiple layer opposite end portions for attachment to the enclosed tendon. The manner in which the graft is sutured to the tendon is illustrated in FIG. 6.
FIG. 8 shows the tubular segment of intestinal submucosa 40 folded back on itself to join its end portions 42, 44 to provide a first connective portion 46 to be attached, for instance, to a first bone and also to provide a bend indicated at 48 in the intermediate portion of the segment 40 to provide a second connective portion to be attached to a second bone articulated with respect to the first bone. The segment arrangement in FIG. 8, therefore, illustrates a method of using a double segment or multilayered segment of intestinal submucosa tissue in accordance with this invention.
FIG. 9 illustrates another method in which a segment 60 of intestinal submucosa is pulled within another tubular segment 62 of intestinal submucosa to provide a dual segment or double segment arrangement having greater strength.
Presently, it is believed that forming the present grafts to have the stratum compactum layer of the intestinal submucosa internally, at least in the intermediate portion, will promote graft vascularization, and tests have been made to establish this fact. It should be recognized, however, that having the stratum compactum on the exterior may function likewise to allow or even promote graft vascularization, and future tests may establish this fact. For instance, it will be appreciated that the arrangement shown in FIGS. 5, 6 and 7, the multiwrap arrangement, is such that the stratum compactum of the outer wrap is against the tunica submucosa of the inner wrap.
The grafts may be sterilized using some conventional sterilization techniques including glutaraldehyde tanning with glutaraldehyde, formaldehyde tanning at acidic pH, propylene oxide treatment, gamma radiation, and peracetic acid sterilization. A sterilization technique which does not significantly weaken the mechanical strength and mechanical properties of the graft is preferably used. For instance, it is believed that strong gamma radiation may cause loss of strength in the graft material. Because one of the most attractive features of these intestinal submucosa grafts is the host-remodelling responses, it is desirable not to use a sterilization approach which will detract from that property.
It is presently believed that a suitable graft material should have a uniaxial longitudinal tensile strength of at least 3.5 MPa and a strain of no more than 20% with maximal load; a burst point of at least 300 mmHg for a specimen that is originally 100 microns thick and shaped in a tube of approximately 3 mm internal diameter; and a porosity that is between 0.5 and 3.0 ml at 120 mmHg pressure per square centimeter. As indicated above, it is presently believed that the most available appropriate source for such intestinal submucosa graft may be the small intestine from 400 to 600 lb. sows which are harvested in slaughter houses. The tubular segments from such sows typically have a diameter of about 10 mm to about 15 mm.
The graft material has a characteristic stress-strain relationship. Because orthopedic application of the graft construct will most often involve stress upon the graft, it is desirable that the graft material be "pre-conditioned" by controlled stretching prior to use as a connective tissue replacement.
One method of "pre-conditioning" involves application of a given load to the intestinal submucosa graft material for three to five cycles. Each cycle consists of applying a load of approximately two megapascals to the graft material for five seconds, followed by a ten second relaxation phase. It has been found that three to five cycles causes approximately twenty percent strain. The graft material does not return to its original size; it remains in a "stretched" dimension.
To date, several studies have been made that relate to orthopaedic applications of the type described above in connection with the drawings using intestinal submucosa harvested from sows. These studies include 14 dogs in which intestinal submucosa has been implanted as an anterior cruciate ligament, six dogs in which intestinal submucosa has been implanted as a medial collateral ligament and nine dogs in which intestinal submucosa has been used as an achilles tendon. In a separate single animal, intestinal submucosa has been used as a "fracture wrap". Some of these animals have been euthanized and the grafts harvested for evaluation.
Results of three dogs with anterior cruciate ligament replacements have been evaluated to show that the tensile strength of the intestinal submucosa graft was at least 70% of the contralateral normal anterior cruciate ligament (ACL) by 10 weeks post-surgery. These evaluations show that the graft was approximately three times the thickness at 10 weeks than it was at the time of the implantation, and it was well vascularized. The intestinal submucosa ACLs also become covered with synovium within two to three weeks and incorporate into the bone through the bone tunnels extremely rapidly and strongly. The longest survivors at this time are approximately eight months and appear to be doing well.
Two dogs with the intestinal mucosa medial collateral ligament have also been sacrificed to show aggressive fibroblastic ingrowth at one month post-surgery with synovial lining of the articular surface. The graft is attached firmly to the extra-articular aspect of the medial meniscus. There was almost complete restoration of medial stability of the knee within four weeks of implantation. At this time, the remaining five dogs with intestinal submucosa medial collateral ligaments are clinically normal with no instability.
Three dogs with achilles tendon replacements with intestinal submucosa have been sacrificed. Of the three groups of dogs, this group showed the most visible evidence of graft remodelling (probably because of location). The grafts thicken to the normal achilles tendon thickness within approximately four to six weeks and can support the normal weight of the animal without a brace within one month. The remodelled connective tissue shows extensive vascularization and orientation of the collagen fibrils along the lines of stress. The only inflammation that was present was represented by small accumulations of mononuclear cells near the suture material, just as would be seen in any surgical wound. The intestinal submucosa grafts appear to develop a peritenon that is synovialized and the boundary between the normal achilles and the intestinal submucosa graft was no longer recognizable with H&E stained histologic tissue sections by 16 weeks post-surgery. Six dogs remain to be sacrificed in this group and the longest survivor is now approximately six months post-implant.
The bone tunnels with the encompassed intestinal submucosa grafts have never been shown to be the weak point in tensile strength evaluations after sacrifice of dogs that have had the intestinal submucosa ACL surgery. In addition, the test animals have not had any infection problem with any of the orthopaedic applications to date. | Surgical repair of diseased or damaged endogenous connective tissue can be accomplished using a tissue graft formed from a delaminated segment of intestinal tissue. The tissue graft comprises the intestinal tunica submucosa, muscularis mucosa and stratum compactum delaminated from the tunica muscularis and the luminal portion of the tunica mucosa. The graft can be conditioned by stretching and formed as a multilayer composition for high tensile strength and resistance to tearing at its points of attachment to existing physiological structures. | 0 |
TECHNICAL FIELD
[0001] The present disclosure relates generally to injector controls, and more specifically to a process, system, and apparatus for detecting a closing time and status of a solenoid injector.
BACKGROUND OF THE INVENTION
[0002] The global drive to reduce NOx and CO2 emissions from diesel engine exhausts has led to the implementation of selective catalytic reduction systems in diesel engine vehicles to reduce the automotive emissions. Selective catalytic reduction systems operate by adding a gaseous or liquid reductant to the exhaust gas stream from an engine. The gaseous or liquid reductant is absorbed onto a catalyst where the reductant reacts with nitrogen oxides in the exhaust gas to form water vapor and nitrogen.
[0003] This treatment requires the reducing agent to be administered at a precise concentration and with high quality. The solution must be accurately metered and injected into the exhaust gas stream, where it is hydrolyzed before converting the nitrogen oxide (NOx) to nitrogen (N2) and water (H2O).
[0004] As the tailpipe NOx emission standard becomes increasingly stringent, it is desired to diagnose the injection faults to assist with the SCR DeNOx functionality and performance. For example, a stuck injector may cause under-dosing of urea and thus reduced DeNOx functionality.
[0005] In order to properly interact with on-board diagnostic systems, such as OBD or OBDII, existing selective catalytic reduction systems include self-diagnostics to identify faults and enable pin point replacement while the vehicle is being serviced. For example, pressure changes may be monitored after commanding the pump to run or shut down. One drawback of this method, however, is that the emissions control process is disrupted. Accordingly, new systems and methods of detecting the SCR closing time are desired.
[0006] In addition, determining closing time of injectors for direct fuel injection is also desired, in order to provide for better control and improved fuel economy.
SUMMARY OF THE INVENTION
[0007] Disclosed is an apparatus, system, and method for detecting a closing time of a valve, such as an SCR valve or a direct injection valve, without additional hardware and without disrupting the emissions control process. The invention may include employing a digital filter and a slope discriminator is developed, which enables a diagnostic function to accurately detect injector closing time and reliably identify a stuck closing injector by monitoring injector current on an injection-to-injection basis.
[0008] In one form, a method for detecting a closing time of an injector valve is provided. The method includes receiving a valve current profile of the injector valve, processing the valve current profile using at least a slope discriminator, determining a stuck status of the injector valve based on an output of the slope discriminator, and if the injector valve is not stuck, determining the closing time of the injector valve based on the output of the slope discriminator.
[0009] In another form, an engine control unit configured to detect a closing time of an injector valve is provided. The engine control unit includes a first control logic configured to receive a valve current profile of the injector valve, a second control logic configured to process the valve current profile using at least a slope discriminator, and a third control logic configured to determine a stuck status and a closing time of the injector valve based on an output of the slope discriminator.
[0010] In yet another form, a vehicle system is provided that includes an exhaust system including an injector and at least one sensor operable to detect a current draw of the injector. The vehicle system also includes a controller connected to the at least one sensor. The controller is operable to receive a profile of the current draw of the selective catalytic reduction injector and to process the profile using a slope discriminator. The controller is also operable to determine a stuck status and a closing time of the injector based on an output of the slope discriminator.
[0011] In still another form, the present disclosure provides a non-transitory machine-readable medium that provides instructions, which when executed by a machine, cause the machine to perform operations. The operations include receiving a valve current profile of the injector valve, processing the valve current profile using at least a slope discriminator, and determining a stuck status and a closing time of the injector valve based on an output of the slope discriminator.
[0012] In still another form, a method for controlling an injector is provided. The includes the steps of: instructing an injector to begin closing using a controller; receiving an injector current profile of the injector at the controller; processing the current profile using at least a slope discriminator in the controller; and determining stuck status and a closing of the injector based on an output of the slope discriminator.
[0013] These and other features of the present invention can be best understood from the following specification and drawings, the following of which is a brief description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] The following figures are provided for illustration purposes only, and are not intended to limit the scope of the present application and claims:
[0015] FIG. 1 is a schematic side view of a vehicle including a selective catalytic reduction injector for reducing emissions, in accordance with the principles of the present disclosure;
[0016] FIG. 2A is a graph of a current profile of a selective catalytic reduction injector and a current profile of a stuck selective catalytic reduction injector with respect to time, according to the principles of the present disclosure;
[0017] FIG. 2B is a zoomed-in portion of the graph of FIG. 2A , illustrating a current profile of a selective catalytic reduction injector and a stuck selective catalytic reduction injector at and around closing time, in accordance with the principles of the present disclosure;
[0018] FIG. 3 is a block diagram illustrating a process for detecting a closing time and status of an injector, according to the principles of the present disclosure;
[0019] FIG. 4 is a graph illustrating a slope discriminator scheme for the process of FIG. 3 , in accordance with the principles of the present disclosure; and
[0020] FIG. 5 is a graph illustrating an output chart of a slope discriminator, according to the principles of the present disclosure.
DETAILED DESCRIPTION
[0021] FIG. 1 schematically illustrates a vehicle 10 including an exhaust system 20 for expelling exhaust 30 from an internal combustion engine of the vehicle 10 . The exhaust system 20 includes a selective catalytic reduction injector 40 that adds a gaseous or liquid reductant to the exhaust gas stream from the engine. The gaseous or liquid reductant is absorbed onto a catalyst where the reductant reacts with nitrogen oxides in the exhaust gas to form water vapor and nitrogen. The selective catalytic reduction injector 40 is controlled by a controller 50 , and includes a sensor package capable of sensing inputs to and outputs from the selective catalytic reduction injector 40 . In one example, the injector 40 is in the form of a solenoid valve.
[0022] One of the inputs that the sensor package can detect, and communicate back to the controller 50 , is a current draw of the selective catalytic injector 40 . This current draw can be aggregated by the controller 50 to determine a current profile of the selective catalytic reduction injector 40 . Based on the current profile of the selective catalytic reduction injector 40 , the controller 50 can determine a precise injector closing time and whether the injector is stuck or unstuck using the below described process.
[0023] The current profile of the selective catalytic reduction injector 40 is a function of battery voltage supplied to the injector, injector temperature and injector fluid pressure. At the conditions of low temperature, low pressure, and high voltage, the current profile of a nominal selective catalytic reduction injector 40 is almost the same as (superficially similar to) a stuck selective catalytic reduction injector, and a top level, or visual, inspection of the current profile is insufficient to identify a stuck injector or to precisely identify the closing time of the injector 40 .
[0024] Though an SCR injector 40 is shown in FIG. 1 , it should be understood that any type of solenoid injector could be used, such as a solenoid port fuel injector or a solenoid direct fuel injector. Solenoid fuel injectors also have a current draw, from which a current profile can be aggregated by a controller, such as controller 50 . Accordingly, the principles described here may apply to a solenoid fuel injector, as well as an SCR injector 40 , or any injector with an inductance reaction upon opening or closing.
[0025] With continued reference to FIG. 1 , FIGS. 2A-2B illustrate a current profile 110 of a selective catalytic reduction injector 40 and a current profile 120 of a stuck selective catalytic reduction injector 40 with respect to time. FIG. 2B is an enlarged view of the end of injection. When the injector 40 is desired to be closed, the current is clamped and the injector begins to close at a time period c. After a delay period d, the non-stuck injector 40 has a post-clamp hump 112 in its current profile 110 , and the stuck injector 40 has a post-clamp hump 114 in its current profile 120 . The post-clamp hump 112 of the non-stuck injector is larger than the post-clamp hump 114 of the stuck injector, that is, the injector that does not fully close. The delay period d is a calibration value. The purpose of delay is to reduce the length of injector current data buffer, and avoid injector current clamp.
[0026] A data collection window of a current profile 110 , 120 is the window during which the analog-to-digital converter (ADC) of controller 50 collects injector current profile data for detecting the current drawn by the injector 40 . The ADC of controller 50 can be configured to read and filter injector closing data with a high sampling rate. During this window 116 , the injector closing current data is processed by the ADC of controller 50 and stored in a data buffer. The data in the buffer can be fed to a slope discriminator to determine the selective catalytic reduction injector 40 stuck status and closing time. The slope discriminator can be another controller, a software module stored in a memory of the controller 50 , or any other similar system. For example, the controller 50 can be configured to receive the valve current profile 110 , 120 , process the valve current profile with the slope discriminator, and determine the stuck status and the closing time (if applicable) of the injector valve based on the output of the slope discriminator.
[0027] With continued reference to FIG. 1 , FIG. 3 illustrates a process 200 utilized by the controller 50 to detect the stuck status and closing time of the selective catalytic reduction injector 40 . As described above, the process 200 may alternatively apply to a solenoid fuel injector, rather than an SCR injector 40 . Initially, the controller 50 checks to see if injection has ended in an end of injection check step 210 . If injection has not ended, the process 200 loops back, and the end of injection check step 210 is performed again after any suitable delay.
[0028] If injection has ended, the process 200 starts a delay timer in step 212 . The delay timer step 212 causes delay for a predetermined, calibrated period of time. As illustrated in FIG. 2B , there is a delay period d between when the injection ends and when the detection window 116 opens. In the step 212 , the controller 50 waits the delay period between the end of injection and the beginning of the detection window 116 before moving on to detect the stuck status and closing time.
[0029] Next, the process 200 moves to a check step 214 of whether the delay timer has expired. If the delay timer has not expired when the controller 50 performs the delay timer expired check 214 , the process 200 loops back to wait for the delay timer to expire and checks again at step 214 . The delay timer is updated every time when the function is executed.
[0030] If, however, the delay timer has expired, the controller 50 begins collecting and filtering current data to construct an injector closing current profile of the injector 40 in a collect injector closing data step 218 . The current data can be processed using any acceptable sensor arrangement. In some examples, the current data is collected using an extremely high sampling rate. The sampling rate is the rate at which data samples are detected. By way of example, a sampling rate of 1 microsecond corresponds to one current detection occurring every microsecond, and this sampling rate may be used in the current application.
[0031] After the collect injector closing data step 218 , the process moves to a check step 220 to determine whether data collection is complete. If data collection is not complete, the process 200 loops back around to the collect injector closing data step 218 , in the collection window 116 . After it is determined in step 220 that data collection is complete, the process 200 moves to step 222 .
[0032] In order to reduce the detected current data to a manageable condition and amount, the detected data may be filtered by the controller 50 to remove high frequency noise using a standard digital filter. In example utilizing a high sampling rate, the data may be further downsampled using known downsampling techniques to reduce the amount of data in the current profile. The filtered and downsampled data forms an injector closing current profile, such as the current profiles 110 , 120 illustrated in FIGS. 2A-2B . The processed injector closing current profile data is stored in the injector closing data buffer. Once the current profile has been determined, the controller 50 , or another device, applies a slope discriminator process to the current profile in an apply slope discriminator step 222 . Because the injector closing current profile data has been stored in the buffer, the steps 222 , 224 and 226 can be executed according to systems task scheduling. The process performed by the slope discriminator is described below in greater detail with regards to FIG. 4 .
[0033] The slope discriminator may utilize nonlinear digital filtering techniques to distinguish the difference in the slope between a stuck injector and a non-stuck injector during closing time. Thus, after the step 222 of applying the slope discriminator, the process 200 moves on to determine the injector closing time (if not stuck) and/or the stuck status of being stuck or not stuck in step 224 .
[0034] Once the closing time and/or stuck status of the injector 40 has been determined, the controller 50 reports the stuck status and/or the closing time in a report closing time and status step 226 . The reporting can be to another separate controller, a subprogram within the controller 50 , or a diagnostic system, such as an OBD (On-Board Diagnostic) or OBDII (On-Board Diagnostic II). Alternately, the closing time and status can be reported to any other system where the opening time and status of the injector 40 is needed.
[0035] With continued reference to FIG. 1 , FIG. 4 is a graph 300 illustrating a current profile 302 of an injector 40 , which shows the principles of the slope discriminator. As described above, in order to determine the current profile 302 , the controller 50 may utilize a nonlinear digital filtering technique to remove noise and downsamples the data to decrease the amount of data, thereby decreasing the data buffer size. Once the current profile 302 has been determined, the controller 50 applies the slope discriminator.
[0036] The slope discriminator utilizes a modified median filter to determine a slope of the injector profile 302 . The slope discriminator processes the current profile 302 entry by entry, replacing each entry with the centered value of neighboring entries falling within a median window 320 to determine a median current profile. The entries within the median window 320 are then sorted in increasing value. The slope discriminator further processes the current profile 302 entry by entry, replacing each entry with the mean value of neighboring entries falling with a mean window 310 to determine a mean current profile.
[0037] As can be seen in FIG. 4 , the mean window 310 is a smaller window (encompasses fewer neighboring data points) than the median window 320 . Further, the mean window 310 falls entirely within the median window 320 . The starting edge of the mean window 310 may be offset from the starting edge of the median window 320 by an offset value. The size of both the mean window 310 and the median window 320 , as well as the size of the offset, are calibration values that can be experimentally or mathematically determined for a particular selective catalytic reduction injector 40 by one of skill in the art having the benefit of this disclosure. Due to the required size of the windows 310 , 320 , the initial output of the slope reflection detection process occurs at point 340 , and not at a start time 304 of the current profile 302 . In the illustrated example of FIG. 4 the initial output 340 of the slope discriminator occurs at the end point of the initial mean window 310 .
[0038] The value of the output at point 340 , and all output values 302 , is determined by the following relationship:
[0000] Output=median term*gain factor for median term−(mean term*gain factor for mean term−offset term);
[0039] where Output is the output value;
[0040] median term is the center value of the median window 320 , which is calculated in sliding window 320 entry by entry;
[0041] mean term is the mean value of the mean window 310 , which is calculated in sliding window 310 entry by entry;
[0000] gain factor for median term=1+abs(median term−mean term); and
[0000] gain factor for mean term=1−abs(median term−mean term);
[0000] offset term=abs(median term−mean term)/length of median sliding window 320 .
[0042] As known in mathematics, “abs” is the absolute value function. Thus, the gain factors are variable gain factors, which depend on the difference between the median term and the mean term. The gain factor for the median term is always greater than or equal to one; and the gain factor for the mean term is always less than or equal to one. The offset term is also related to the difference between the mean term and the median term.
[0043] As a result of the above relationships, the bigger the difference between the value of the median window 320 and the mean window 310 , the greater the factor gain factor for the median term will be. Similarly, the bigger the difference between the value of the median window 320 and the mean window 310 , the smaller factor gain factor for the mean term will be. This difference in the gain factors results in an output term that greatly magnifies the slope, thus showing a separation between the stuck injector current profile and the non-stuck injector closing profile at closing time.
[0044] With continued reference to FIGS. 1 and 4 , FIG. 5 illustrates an output graph 400 showing outputs of the slope discriminator for non-stuck and stuck SCR injectors 40 . The outputs for a normal, non-stuck injector are graphed at line 410 , and the outputs for a stuck injector are graphed at line 420 . The location of the maximum value 422 of the normal injector output plot 410 indicates that the SCR injection needle is fully closed. Since there is a large separation between the stuck and non-stuck profiles 420 , 410 , a predetermined calibrated threshold 424 can be determined, to which the profiles 410 , 420 can be compared. For example, if any of the profile 410 , 420 is above the threshold 424 , then the SCR injector can be determined to be non-stuck; and if any of the profile 410 , 420 is below the threshold 424 , the SCR injector can be determined to be closed. Based on this difference, the controller 50 can detect when the selective catalytic reduction injector 40 is stuck (i.e. when any of the output profile 410 , 420 exceeds the predetermined threshold 424 ).
[0045] The precise injector closing time can be easily calculated based on the location of the maximum value 422 . The precise closing time of the selective catalytic reduction injector 40 is precise to within a time period of the downsampled data rate. Thus, if the downsampled data rate is 1 microsecond, the time of the maximum value point 422 can fall within 1 microsecond of the actual fully open time of the selective catalytic reduction injector 40 , depending on the system tolerances and slope discriminator filter calibration.
[0046] By utilizing the above described process, the controller 50 can determine the precise closing time of a selective catalytic reduction injector and whether the selective catalytic reduction injector is stuck or non-stuck. As can be appreciated by one of skill in the art having the benefit of this disclosure, the above described process can be applied to any number of injector valves exhibiting similar slope reflection characteristics, and is not limited to selective catalytic reduction injectors.
[0047] It is further understood that any of the above described concepts can be used alone or in combination with any or all of the other above described concepts. Although an embodiment of this invention has been disclosed, a worker of ordinary skill in this art would recognize that certain modifications would come within the scope of this invention. For that reason, the following claims should be studied to determine the true scope and content of this invention. | A method for detecting a closing time of an injector valve includes receiving a valve current profile of the injector valve, processing the valve current profile using at least a slope discriminator, determining a stuck status and a closing time (if applicable) of the injector valve based on an output of the slope discriminator. An engine control unit configured to detect a closing time of an injector valve is also provided. The engine control unit has a first control logic configured to receive a valve current profile of the injector valve, a second control logic configured to process the current profile using at least a slope discriminator, and a third control logic configured to determine a stuck status and a closing time of the injector valve based on an output of the slope discriminator. Further, a vehicle system including a controller configured to detecting a valve closing time is provided. | 8 |
The present application is based on Japanese Patent Applications Nos. 2003-100638 and 2003-343646, the entire contents of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a recording apparatus. Further, the invention relates to a liquid ejecting device such as an ink jet recording apparatus for ejecting liquid such as ink from its head into an ejection medium.
The liquid ejecting device is not restricted to a recording apparatus including a printer, a copy, and a facsimile which uses an inkjet recording head in order to discharge the ink therefrom into the recording medium, for performing a recording, but it includes a liquid ejection apparatus for ejecting the liquid corresponding to the same purpose, instead of ink, into the ejection medium corresponding to the recording medium, from a liquid ejection head corresponding to the recording head and attaching the above liquid to the ejection medium.
The liquid ejection head includes a color material ejection head for use in color filter manufacture such as a liquid crystal display, an electrode material (conductive paste) ejection head for use in electrode formation such as an organic EL display and a field emission display (FED), a living organic matter ejection head for use in bio chip manufacture, and a sample ejection head as an accurate pipette, other than the recording head.
2. Related Art
In the recording apparatus having a recording head, it is necessary to change a space between the recording head and the upper surface of the platen, that is, a platen gap, depending on the thickness of a recording medium. As the conventional technique for changing the platen gap, there is a technique, as disclosed in Japanese utility model publication No. JP-U-H05-35311, in which the thickness of paper set at the printing section is detected, the gap amount of a printing head is corrected by using a correction value predetermined depending on the detected thickness of the paper, and a print head gap suitable for the paper to be printed is set.
Further, in Japanese Patent publication No 3027974B2, there is an apparatus comprising: a stepping motor for moving a carriage on which a recording head is mounted in a vertical direction of a platen; a rotary encoder with a detection mark provided on its circumference for supplying pulse signals in proportion to the quantity of rotation of the motor, that is, the moving quantity of the carriage; time lag integrating means for moving the carriage from a reference position into the direction of the platen to calculate the integrated value of the time lag between the pulse signal from the rotary encoder and the drive pulse of the stepping motor; and contact judging means for detecting that the integrated value reaches a predetermined value, in which paper thickness calculating means calculates the thickness of the paper according to the number of pulses of the rotary encoder up to the time when the signal is supplied from the contact judging means.
SUMMARY OF THE INVENTION
Although a platen gap has to be switched in several stages depending on the thickness of the recording medium to be used, in the case of switching it by using a cam, there occurs a transition area from the stable area to the next stable area, other than an area where the platen gap becomes stable.
When the turning phase angle of the cam a little deviates because of tolerance, the platen gap is determined at the transition area and accordingly there is a possibility of failing to get the accurate platen gap. An object of the invention is to provide a stable area detection device of a platen gap and a recording apparatus in which a cam can rotate at such an accurate phase angle to get the platen gap in the stable area.
In order to achieve the above object, the invention provides a stable area detection device for a platen gap formed between a head and an upper surface of a platen, in a platen gap adjustment device, the platen gap adjustment device including
a carriage guide shaft,
a guide shaft gear fixed to an end of the carriage guide shaft,
a gap adjuster cam rotatable integrally with the guide shaft gear and formed in a shape to change the platen gap in a plurality of platen gap stages,
a cam follower for the gap adjuster cam, and
a drive motor for driving the guide shaft gear to rotate,
wherein the carriage guide shaft is moved relatively to the platen so that the platen gap is adjusted by driving the drive motor to rotate the gap adjuster cam,
the gap adjuster cam is configured so as to provide a plurality of stable areas corresponding to the platen gap stages where the platen gap is constant while a rotational phase of the gap adjuster cam varies in a predetermined range and
a plurality transition areas where the platen gap changes between the stable areas as the rotational phase of the gap adjuster cam varies;
wherein a stable area detection sensor is provided so as to face to a rotational member which rotates synchronously with the gap adjuster cam, and
a detection object in correspondence with the stable areas of the platen gap is provided on the rotational member.
According to the first aspect of the invention, since the gap adjuster cam is prevented from standing in the transition area where there is a change in the platen gap, it is possible to perform the recording on the recording medium at high quality.
The stable area detection device of platen gap according to the second aspect of the invention is constituted in that
in addition to the first aspect, the stable area detection sensor includes a light emitting portion and a light receiving portion and
the detection object comprises a light shielding plate which passes between the light emitting portion and the light receiving portion. According to this aspect, since the light shielding plate prevents the light receiving portion from receiving the light emitted from the light emitting portion, the light shielding state or the light passing state can be detected as the stable area.
The stable area detection device of platen gap according to the third aspect of the invention is constituted in that, in addition to the first aspect or the second aspect, the detection object detected by the detection sensor for the stable areas is formed in correspondence with a central portion in each stable area, other than adjacent portions to the transition areas formed in both ends of said stable area. According to this aspect, it is possible to prevent the stable area detection sensor from misidentifying the transition area to be the stable area.
The stable area detection device of platen gap according to the fourth aspect of the invention is constituted in that, in addition to one of the first aspect to the third aspect, a home position detection sensor is provided so as to face to the rotational member, and
the rotational member is provided with anther detection object for the home position detection sensor at a position where the gap adjuster cam is located in a home position. According to this aspect, since the home position of the gap adjuster cam can be detected easily, it can contribute to the improvement of throughput.
The stable area detection device of platen gap according to the fifth aspect of the invention is constituted in that, in addition to the fourth aspect, the position where the gap adjuster cam is located in the home position is a boundary portion between the stable area of a maximum platen gap stage and the transition area adjacent to the stable area of the maximum platen gap stage. According to this aspect, even when a user turns on the printer without knowing there is foreign substance under the recording head, since the platen gap is enough, it is possible to decrease a possibility of damaging the recording head owing to the foreign substance, through the scanning operation of the recording head.
The stable area detection device of platen gap according to the sixth aspect of the invention is constituted in that, in addition to one of the first aspect to the third aspect, the gap adjuster cam includes a restricting mechanism for restricting a rotation thereof so as to be rotatable in a range from the stable area of a minimum platen gap stage to the stable area of the maximum platen gap stage.
In this aspect, according to the restricting mechanism for restricting the rotation range of the gap adjuster cam so as to be rotatable in a range from the stable area of the minimum platen gap to the stable area of the maximum platen gap, when the stable area sensor detects no change for a predetermined hour even when a driving force is given to the gap adjuster cam, it is possible to recognize that it means the minimum platen gap or the maximum platen gap, figuring out the current position without providing another sensor for the exclusive use.
The recording apparatus of the invention for performing a recording on a recording medium comprises the stable area detection device of platen gap, according to one of the first aspect to the sixth aspect. According to this aspect, since the platen gap can be always kept at a stable distance, it is possible to perform the recording on the recording medium at high quality.
The liquid ejection apparatus of the invention for ejecting a liquid on a liquid ejection medium comprises the stable area detection device of platen gap, according to one of the first aspect to the sixth aspect.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross sectional side view of the recording apparatus having the stable area detection device of the platen gap according to the invention;
FIG. 2 is a cross sectional side view showing the state of feeding the stiff recording medium;
FIG. 3 is a perspective view of the transport-driven roller holder and its vicinity when feeding the flexible recording medium;
FIG. 4 is a perspective view of a driving force transmission branch gear and its vicinity;
FIG. 5 is a cross sectional side view showing the state of engagement of the driving force transmission branch gear and its vicinity;
FIG. 6 is a perspective view showing the structure of vertically moving the carriage guide shaft;
FIG. 7 is a front view showing the structure of a gap adjuster cam and its vicinity;
FIG. 8 is a side view of the driving force transmission branch gear and its vicinity;
FIG. 9 is a graph showing the PG displacement, the retreating operation of the transport-driven roller, and the sensor detection state;
FIG. 10 is a top view showing a sensor provided in a disc coaxial with the guide shaft gear;
FIGS. 11A and 11B are perspective views showing the sensor provided in a disc coaxial with the guide shaft gear according to the second embodiment;
FIGS. 12A and 12B are a perspective view and a side view showing the structure of vertically moving the carriage guide shaft;
FIG. 13A is a front view showing the structure of vertically moving the carriage guide shaft;
FIG. 13B is a front view showing the structure of vertically moving the carriage guide shaft;
FIG. 13C is a front view showing the structure of vertically moving the carriage guide shaft;
FIG. 13D is a front view showing the structure of vertically moving the carriage guide shaft; and
FIG. 14 is a graph showing the PG displacement and the sensor detection state.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
<First Embodiment>
Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a cross sectional side view showing an ink jet printer (hereinafter, referred to as a printer) as one example of a recording apparatus including a stable area detection device of platen gap, according to the invention, FIG. 2 is a cross sectional side view showing the state of feeding a stiff recording medium, FIG. 3 is a perspective view of a transport-driven roller holder and its vicinity when feeding a flexible recording medium. Although the invention can be applied to an ejection medium on which surface, instead of ink, liquids corresponding to other applications are ejected, other than the recording medium such as paper and the like, the recording medium will be hereafter described representatively.
A printer 1 comprises a feeding section 2 for feeding a recording medium P, at the upstream side and the feeding section 2 keeps a stack of the recording mediums P in a slanting state and transports the recording mediums P one by one to the downstream. When the recording medium is flexible like paper, the recording medium is transported to the recording process through a feeding path as illustrated in the circled number 1 in FIG. 1 , when the recording medium has rigidity (stiff recording medium), it is transported to the recording process through the feeding path as illustrated in the circled number 2 in FIG. 2 .
The feeding section 2 comprises a hopper 16 and the hopper 16 holds a stack of the recording mediums in a slanting state. The hopper 16 is provided with a rotational support point at the upstream side and by turning around the rotational support point, it is formed so as to release or contact with a feeding roller 14 formed in a substantially D-shape from a side view. The recording medium P is pushed up by the clamping operation toward the feeding roller 14 and the uppermost one of the recording mediums P is made into contact with the feeding roller 14 . In this state, the feeding roller 14 is rotated so as to transport the recording medium P to the downstream.
A plate-shaped guide 15 is provided almost horizontally in the downstream of the feeding roller 14 , and the distal end of the recording medium P transported from the feeding section 2 is in contact with the guide 5 and smoothly and flexibly directed to the downstream. A transporting roller 19 including a transport-driving roller 19 a of rotationally moving by a driving unit not illustrated and a transport-driven roller 19 b of rotating together in contact with the transport-driving roller 19 a is provided in the downstream from the guide 15 , and the recording medium P is pressed by the transporting roller 19 and given a driving force to the downstream. The transport-driving roller 19 a is formed in a cylindrical roller long in a main scanning direction and a plurality of the transport-driven rollers 19 b are provided shortly in the main scanning direction at predetermined intervals in the main scanning direction.
The transport-driven roller 19 b is supported by a shaft on the downstream side of the transport-driven roller holder 18 . The transport-driven roller holder 18 is provided in a rotative way around the rotation axis 18 a , and the transport-driven roller 19 b is always urged rotationally into close contact with the transport-driving roller 19 a by a helical torsion spring (not illustrated).
The transport-driven roller 19 b can be turned into a retreat state of retreating upwardly by the rotation of the transport-driven roller holder 18 around the rotational support point 18 a , as illustrated in FIG. 2 .
Namely, a cam 36 is provided in a driven roller release shaft 31 in a way of coming into contact with a cam follower 18 b on the upstream portion of the transport-driven roller holder 18 , the cam 36 is coming into contact with the cam follower 18 b from top down, according to the rotation of the release shaft 31 , and the transport-driven roller holder 18 is rotated around the rotational support point 18 a . Thus, the transport-driven roller 19 b retreats upwardly, to thereby be in a retreat state as shown in FIG. 2 . When the cam 36 's contact with the cam follower 18 b is released, the transport-driven roller 19 b is rotationally urged toward the transport-driving roller 19 a by the helical torsion spring (not illustrated) and returned into a contact state as shown in FIG. 1 . Here, a reference mark P G is attached particularly to the stiff recording medium which is difficult for the transporting roller to nip, for distinction.
Further, a recording section 26 for performing a recording on the recording medium P is provided on the downstream of the transporting roller 19 . A platen 28 and a recording head 13 are arranged in the recording section 26 so as to vertically oppose to each other. The platen 28 is formed long in the main scanning direction and supports the recording medium P transported to the recording section 26 upwardly.
The recording head 13 is provided in the bottom of a carriage 10 capable of holding an ink cartridge 11 and the carriage 10 can reciprocate in the main scanning direction while being directed by a carriage guide shaft 12 extending in the main scanning direction. The distance between the upper surface of the platen 28 and the recording head 13 , that is, a platen gap (hereinafter, there may be some cases of abbreviating as PG) is an important element for determining the recording accuracy, and it is necessary to properly adjust it depending on the thickness of the recording medium P. The PG adjustment will be described later.
The downstream portion from the recording section 26 forms a discharge portion of the paper P in the printer 1 , which is provided with a discharge roller 20 including a discharge-driving roller 20 a of rotationally moving by the driving means not illustrated and a discharge-driven roller 20 b of being driven while being lightly clamped with the discharge-driving roller 20 a . The recording medium P on which the recording by the recording section 26 has been performed is clamped by the discharge roller 20 and discharged onto a stacker 50 according to the rotation (normal rotation) of the discharge-driving roller 20 a.
The discharge-driven roller 20 b is a toothed roller having a plurality of teeth around its outer periphery and supported by a discharge-driven roller holder 23 in a rotatable way. The discharge-driven roller holder 23 is formed in a plate shape long in the main scanning direction and it is fixed to a discharge sub frame 25 extending almost horizontally from the vicinity of the recording head 13 toward the downstream along the discharge path of the recording medium P. The discharge sub frame 25 is attached to a discharge main frame 24 long in the main scanning direction and formed in a plate shape extending substantially horizontally from the vicinity of the recording head 13 toward the downstream, by a coil spring 27 in a way of downwardly pressing.
A discharge auxiliary roller 22 is provided in the upstream of the discharge-driven roller 20 b and the recording medium P is slightly pressed downward by the discharge auxiliary roller 22 . The position of the core axis of the transport-driven roller 19 b is positioned in the downstream further than that of the transport-driving roller 19 a , and the position of the core axis of the discharge-driven roller 20 b is positioned in the upstream further than that of the discharge-driving roller 20 a . According to this structure, the recording medium P is a little curved and convexed downwardly between the transporting roller 19 and the discharge roller 20 , and the recording medium P facing the recording head 13 is pushed down on the platen 28 , to thereby prevent from floating up of the recording medium P and correctly perform the recording thereon.
The driving mechanism of the cam 36 for retreating the PG adjusting mechanism and the transport-driven roller 19 b upwardly will be described with reference to FIGS. 4 to 8 . FIG. 4 is a perspective view of the vicinity of a driving force transmission branch gear, FIG. 5 is a cross sectional side view showing the state of engagement of the driving force transmission branch gear and its vicinity, FIG. 6 is a perspective view showing the structure of vertically moving the carriage guide shaft, FIG. 7 is a front view showing the structure of a gap adjuster cam and its vicinity, and FIG. 8 is a lateral side view of the driving force transmission branch gear and its vicinity.
As shown in FIG. 4 and FIG. 5 , the printer 1 is provided with a drive motor 51 for driving the PG adjustment device and cam 36 . A driving pulley 52 of the drive motor 51 transmits a driving force to an input gear 55 through an input gear mechanism 53 consisting of a gear train and the input gear 55 is engaged in a driving force transmission branch gear 57 .
As well illustrated in FIG. 5 , the driving force transmission branch gear 57 is formed in three gear stages including a main gear 59 to be engaged in the input gear 55 , a first output gear 61 and a second output gear 63 fixed to the main gear 59 , for integrally rotating together. A toothless portion 65 is formed on one of the outer peripheral portion of the first output gear 61 and the other teeth of the gear can be engaged in an intermediate gear 67 adjacent to the first output gear 61 . The function of the toothless portion 65 in the first output gear 61 will be described later.
The intermediate gear 67 is engaged in a guide shaft gear 69 and a carriage guide shaft 12 is fixed at the center of the guide shaft gear 69 . A gap adjuster cam 71 which rotates synchronously with the guide shaft gear 69 is fixed to the carriage guide shaft 12 adjacent to the guide shaft gear 69 and a fixed pin 73 working as a cam follower is fixed in the vicinity of the gap adjuster cam 71 .
As illustrated in FIG. 6 , FIG. 7 , and FIG. 8 , the carriage guide shaft 12 penetrates into a guide groove 77 extending longitudinally, which is formed on the frame 75 of the printer 1 , and accordingly, only the vertical movement is permitted and the horizontal movement is not permitted. According to this structure, when a rotational driving force is given to the guide shaft gear 69 from the drive motor 51 , the gap adjuster cam 71 begins to rotate and according to the function of the outer peripheral surface of the gap adjuster cam 71 and the fixed pin 73 , the carriage guide shaft 12 moves vertically. As a result, the carriage 10 supported by the carriage guide shaft 12 also moves vertically, to thereby adjust the platen gap (PG).
On the other hand, a toothless portion 79 is also formed in one of the outer peripheral portion of the second output gear 63 and the other teeth of the gear can be engaged in a cam driving gear 81 fixed to the end portion of the driven roller release shaft 31 . The function of the toothless portion 79 in the second output gear 63 will be described later.
According to this structure, when a rotational driving force is given to the driven roller release shaft 31 from the drive motor 51 , the driven roller release shaft 31 and the cam 36 also begin to rotate, and the function of the cam 36 and the cam follower 18 b as mentioned above can realize the state of retreating the transport-driven roller 19 b upwardly and the state of keeping it into contact with the transport-driving roller 19 a.
As mentioned above, use of the driving mechanism for the platen gap adjustment enables the retreat state and the contact state of the transport-driven roller 19 b , and therefore, it is not necessary to prepare for another driving mechanism separately, which makes the structure simple and decreases the cost.
Hereinafter, with reference to FIG. 9 and FIG. 10 , adjustment of a platen gap, and the retreat state and the contact state of the transport-driven roller 19 b realized by the above structure will be described. FIG. 9 is a graph showing a displacement of the platen gap, the retreating operation of the transport-driven roller 19 b , and the detection state of a sensor, according to the rotation of the drive motor 51 , and FIG. 10 is a perspective view showing the sensor provided on a disc 70 (rotational member) coaxial with the guide shaft gear 69 .
In FIG. 9 , the horizontal axis indicates the rotational phase position of the drive motor 51 , the right is the direction of counterclockwise rotation from a viewpoint of the output shaft and the left is the direction of clockwise rotation. A solid line 83 in FIG. 9 indicates a displacement of the platen gap accompanying the rotation of the drive motor 51 and it shows that the displacement becomes larger according to the upper direction of the vertical axis. A broken line 85 continued to the solid line 83 at the right side shows the state in which the toothless portion 65 of the first output gear 61 faces the intermediate gear 67 and therefore the rotational driving force of the drive motor 51 is not transmitted to the gap adjuster cam 71 .
The solid line 87 indicates the displacement of the driven-roller release shaft 31 at a time of performing the retreating and contact operation of the transport-driven roller 19 b , and in this case, the upper direction of the vertical axis indicates how much the transport-driven roller 19 b is removed upward from the contact state, and the horizontal portion 87 a at the right end of the solid line 87 indicates the retreat completion state of the transport-driven roller 19 b . The broken line 89 continued to the solid line 87 at the left side indicates the state in which the toothless portion 79 of the second output gear 63 faces the cam driving gear 81 and therefore the rotational driving force of the drive motor 51 is not transmitted to the driven roller release shaft 31 . The horizontal line indicated by the broken line 89 indicates the contact state of the transport-driving roller 19 a and the transport-driven roller 19 b.
In FIG. 9 , as apparent from the positional relationship between the boundary point 91 of the solid line 83 and the broken line 85 and the boundary point 93 of the solid line 87 and the broken line 89 , the toothless portion 65 of the first output gear 61 is formed in the range of the second output gear 63 and the cam driving gear 81 being in mesh, and contrary, the toothless portion 79 of the second output gear 63 is formed in the range of the first output gear 61 and the intermediate gear 67 being in mesh.
If the driving force of the drive motor 51 is transmitted also to the driven-roller release shaft 31 , when this driving force should be transmitted to the gap adjuster cam 71 through the first output gear 61 , the transport-driven roller 19 b could retreat when it should not and the transport-driven roller 19 b could come into contact with the transport-driving roller 19 a when it should retreat. The reason for forming the toothless portion 79 in the second output gear 63 is to avoid such the draw back.
On the other hand, the reason for forming the toothless portion 65 in the first output gear 61 is to decrease the load on the drive motor 51 by releasing the engagement of the first output gear 61 and the intermediate gear 67 by the toothless portion 65 because the load on the drive motor 51 is increased when the rotational driving force is transmitted to the driven roller release shaft 31 . When it is not necessary to decrease the load on the drive motor 51 , it is not necessary to form the toothless portion 65 in the first output fear 61 .
As shown by the solid line 83 in FIG. 9 , this example can select a platen gap in four stages. The horizontal portion of the solid line 83 indicates stable areas 95 , 96 , 97 , and 98 of PG (−, Typ, +, ++) in the four stages. The stable area 96 indicated by “Typ” corresponds to the PG for the paper having usual thickness, the stable area 95 indicated by “−” corresponds to the PG for thin paper, the stable area 97 indicated by “+” corresponds to the PG for the paper slightly thicker than the usual paper, and the stable area 98 indicated by “++” corresponds to the PG for the further thicker paper. Transition areas 99 , 100 , and 101 for transiting to the respective stable areas are formed respectively between the stable areas 95 and 96 , 96 and 97 , 97 and 98 .
In order to keep the platen gap constant during recording into the recording medium, it is necessary to fix the platen gap at one of the stable areas 95 , 96 , 97 , and 98 not at any of the transition areas 99 , 100 , and 101 . As shown in FIG. 10 , four light-shielding plates 103 a , 103 b , 103 c , and 103 d are formed in a protruding way at intervals on the outer periphery of a disc 70 coaxial with the guide shaft gear 69 , and an optical stable area detection sensor 105 is provided at a position adjacent to the outer periphery of the guide shaft gear 69 . The stable area detection sensor 105 has a light emitting portion and a light receiving portion, and it is to detect the presence of the light shielding plate depending on whether or not the light emitted from the light emitting portion is received by the light receiving portion.
The respective positions of the four light shielding plates 103 a , 103 b , 103 c , and 103 d on the outer periphery of the disc 70 correspond to the respective stable areas 95 , 96 , 97 , and 98 , and when one of the four light shielding plates shields the light of the stable area detection sensor 105 , a judging unit, not illustrated, judges that the platen gap is in the stable area. The judging unit makes a judgment which light shielding plate is now shielding the light and which stable area the GP is standing in, through sequentially shielding the light of the stable area detection sensor 105 by the four light shielding plates 103 a , 103 b , 103 c , and 103 d.
In FIG. 9 , the solid line 107 indicates the position where the light of the stable area detection sensor 105 is shielded, correspondingly to the solid line 83 indicating each stage of the platen gap. As for the solid line 107 , the stepped-up portion indicates “light shield state” and the stepped-down portion indicates “light pass state”. As is apparent from the comparison between the solid line 107 and the solid line 83 , the four light shielding plates 103 a , 103 b , 103 c , and 103 d do not completely conform to each length of the stables areas 95 , 96 , 97 , and 98 , but each circumferential length of the light shielding plates is determined in a way of corresponding to each central area of the stable areas 95 , 96 , 97 , and 98 excluding each transition area and each neighboring end portion. This can prevent the stable area detection sensor 105 from misidentifying the transition area to be the stable area, taking the tolerance into consideration.
As illustrated in FIG. 10 , an arc-shaped light shielding plate 109 is formed in predetermined length on one surface of the disc 70 , and a home position detection sensor 111 including a light emitting portion and a light receiving portion is provided on the same surface of the disc 70 . The home position detection sensor 111 is provided in order to determine the home position of the gap adjuster cam 71 and the solid line 113 of FIG. 9 indicates the light shield and the light pass by the home position detection sensor 111 , correspondingly to the solid line 83 indicating the stages of the platen gap.
As for the solid line 113 , the stepped-up portion on the right indicates the “light shield state” and the stepped-down portion on the left indicates the “light pass state”. As is apparent from the comparison between the solid line 113 and the solid line 83 , it is found that the home position detection sensor 111 turns from the “light pass state” to the “light shield state” at the point when the transition area 101 moves to the stable area 98 as for the solid line 83 . Namely, in this example, the point of moving from the transition area 101 to the stable area 98 where the platen gap becomes the maximum is defined as a home position and the home position can be found by detecting the change from the “light pass state” to the “light shield state” in the home position detection sensor 111 or the inverse change. Further, by defining the point of moving from the transition area 101 to the stable area 98 where the platen gap becomes maximum, as the home position, even when a user turns on the power of the printer 1 without knowing there is foreign substance under the recording head 13 , since the platen gap is enough, it is possible to decrease the possibility of damaging the recording head 13 by the foreign substance through the scanning operation of the recording head 13 .
<Second Embodiment>
Hereinafter, a second embodiment of the invention will be described with reference to FIGS. 11A to 14 . The second embodiment described later is made by changing the structure of the PG adjusting mechanism of the above mentioned first embodiment. Here, FIGS. 11A and 11B are perspective views showing a sensor provided on a disc coaxial with the guide shaft gear, FIGS. 12A and 12B are perspective view and side view showing the structure of vertically moving the carriage guide shaft, FIGS. 13A to 13D are front views each showing the structure of vertically moving the carriage guide shaft, and FIG. 14 is a graph showing the PG displacement and the sensor detection state. In the second embodiment, the same reference numeral is attached to the same component as that in the above-mentioned first embodiment, and the description thereof is omitted.
Although the PG adjusting mechanism according to this embodiment is provided on the left end portion of the carriage guide shaft 12 , the structure of the right end portion will be described at first. In FIGS. 11A and 11B , a guide groove 77 extending along the vertical direction, for supporting the carriage guide shaft 12 is formed on the right surface of the frame 75 formed in a substantially U-shape from lateral side view (the guide groove 77 is also formed on the left surface thereof), and the both ends of the carriage guide shaft 12 are inserted into the guide grooves 77 . The disc 70 is mounted on each shaft end portion of the carriage guide shaft 12 , and four light shielding plates 103 are formed on the outer periphery of the disc at predetermined intervals. Though these light shielding plates are formed in a way of standing at right angles to the disc, differently from the light shielding plates 103 a to 103 d according to the first embodiment shown in FIG. 10 , the other structure and function and effect are the same and they are served for detecting the stable area by the sensor 105 including a light emitting portion and a light receiving portion.
In FIG. 11B , the reference numeral 203 indicates a tension spring as urging means for holding the carriage guide shaft 12 stably, and the reference numeral 201 indicates a plate to be mounted on the right surface of the frame 75 at a predetermined inward angle, in order to hang the tension spring 203 with the carriage guide shaft 12 . The tension spring 203 is hung between a latch hook formed in the plate 201 and a groove formed in the carriage guide shaft 12 and the carriage guide shaft 12 is urged toward three directions including the vertical downward direction, the printer backward direction, and the axis line direction of-the carriage guide shaft 12 , to thereby obtain the following effects.
At first, although the carriage guide shaft 12 is put into the guide groove 77 extending in the vertical direction, a clearance is formed between the guide groove 77 and the shaft in the horizontal direction to some degree. Accordingly, the tension spring 203 urges the carriage guide shaft 12 toward one side inside of the guide groove 77 (in this embodiment, on the printer backward side) so to stabilize the carriage guide shaft 12 within the guide groove 77 without chatter.
At second, though the carriage guide shaft 12 is supported by the both lateral sides of the frames 75 (the details of the supporting portion is not described), it comes loose in the direction of the axis core. Accordingly, the tension spring 203 urges the carriage guide shaft 12 in the direction of the axis core, so to stabilize the above without chatter.
At third, since the carriage guide shaft 12 is provided with a gap adjuster cam 216 (described later) on the left end, as illustrated in FIG. 13A , which comes into contact with the cam follower 211 b (described later) from top down, so to define the platen gap, the tension spring 203 presses the gap adjuster cam 216 against the cam follower 211 b so as not to upwardly displace the gap adjuster cam 216 from the cam follower 211 b . Namely, the above cam serves a function of stabilizing the platen gap without any improper displacement.
As mentioned above, one tension coil spring 201 can stabilize the carriage guide shaft 12 in multi directions at low cost with a little space. On the left end of the carriage guide shaft 12 , although a bar spring 213 shown in FIGS. 12A and 12B pushes the gap adjuster cam 216 against the cam follower 211 b as well as urges the carriage guide shaft 12 to one side within the guide groove 77 so as not to make chatter, the tension spring 203 takes advantage of managing the load more easily than this bar spring 213 .
Sequentially, the PG adjusting mechanism is provided on the left end of the carriage guide shaft 12 as illustrated in FIGS. 12A and 12B . The PG adjusting mechanism of this embodiment changes the PG by transmitting a driving force from the drive motor 51 that is the driving source of exclusive use to the guide shaft gear 215 mounted on the left end of the carriage guide shaft 12 through the first gear 205 , the second gear 207 , and the third gear 209 (these gears are two stepped gears), to thereby rotate the above guide shaft gear 215 . These are all mounted on the left surface of the frame 75 not illustrated.
Hereinafter, the guide shaft gear 215 will be described in detail. The guide shaft gear 215 has a tooth portion to be engaged into the third gear 209 , on one portion of the outer circumference and a toothless portion where a tooth portion is lost, and a projection 218 protruding in the diameter direction is formed in the boundary between the tooth portion and the toothless portion. On the other hand, the gap adjuster cam 216 is formed on the disc surface of the guide shaft gear 215 and a projection 217 protruding in the diameter direction is formed on the cam surface.
A bush 211 for parallelism adjustment is mounted on the vicinity of the guide shaft gear 215 . The parallelism adjustment bush 211 is to adjust the parallelism of the carriage guide shaft 12 and mounted on the both lateral sides of the frame 75 . A cam follower 211 b is formed in the parallelism adjustment bush 211 and the platen gap is defined by the gap adjuster cam 216 pushing against the above cam follower 211 b from top down. Namely, since the cam surface of the gap adjuster cam 216 is formed in a shape of varying the distance from the axis core of the carriage guide shaft 12 that is the rotation axis, the distance from the cam follower 211 b of the carriage guide shaft 12 varies according to the rotation of the guide shaft gear 215 , as illustrated in FIG. 13A to FIG. 13D , thereby changing the platen gap. Further, the parallelism adjustment bush 211 can swing around a hole 211 a for a shaft not illustrated to penetrate, and by this swing, similarly, the platen gap changes. Accordingly, by sliding the both parallelism adjustment bushes 211 on the right and left, adjustment of the parallelism of the carriage guide shaft 12 is possible.
Hereinafter, the restricting mechanism for restricting the rotation range of the gap adjuster cam 216 between the stable area of the minimum platen gap and the stable area of the maximum platen gap will be described with reference to FIG. 14 .
In FIG. 14 , the reference numerals 95 to 98 indicate the respective stable areas and the reference numerals 99 to 101 indicate the respective transition areas, similarly to FIG. 9 . The solid line 107 indicates the position where the light of the stable area detection sensor 105 is shielded, correspondingly to the solid line 83 indicating each stage of the platen gap, similarly to FIG. 9 .
This embodiment is not provided with the home position detection sensor 111 , differently from the above-mentioned first embodiment. Namely, in the minimum platen gap shown in FIG. 13A , since the projection 217 comes into contact with the cam follower 211 b , the further rotation of the gap adjuster cam 216 (guide shaft gear 215 ) is restricted by this. As mentioned above, the gap adjuster cam 216 will be restricted to the rotation range within the above range of from the stable area of the minimum platen gap to the stable area of the maximum platen gap.
The “stopping position” shown in the both sides of FIG. 14 indicates the position of restricting the rotation of the gap adjuster cam 216 as mentioned above and at the reset operation, the drive motor 51 is rotated in the direction of bringing the projection 217 into contact with the cam follower 211 b . Here, when the stable area detection sensor 105 does not change even if applying a drive current to the drive motor 51 for more than a predetermined hour, it is judged that the projection 217 comes into contact with the cam follower 211 b as illustrated in FIG. 13A and namely, it is judged that the current platen gap is the minimum platen gap. Next, the platen gap is changed to the maximum while monitoring the detected signal of the stable area detection sensor 105 in order to seek the home position of the carriage (CR) 10 and again returned to the minimum platen gap, into a printing waiting state.
As mentioned above, without using the home position detection sensor 111 as shown in the first embodiment, the current position of the platen gap can be judged by using the stable area detection sensor 105 , thereby saving the cost.
The invention can be applied to a recording apparatus represented by a facsimile and a printer and a liquid ejecting device, that is, a liquid ejection apparatus for attaching liquid to an ejection medium from a head for ejecting the liquid. | In a platen gap adjustment device, a stable area detection device for a platen gap formed between ahead and an upper surface of a platen, wherein the carriage guide shaft is moved relatively to the platen so that the platen gap is adjusted by driving the drive motor to rotate the gap adjuster cam, the gap adjuster cam is configured so as to provide a plurality of stable areas and a plurality transition areas; and wherein a stable area detection sensor is provided so as to face to a rotational member which rotates synchronously with the gap adjuster cam, and a detection object in correspondence with the stable areas of the platen gap is provided on the rotational member. | 1 |
BACKGROUND OF THE INVENTION
This invention relates to a lower surface contact type contact which is brought into contact, under pressure, with a lower surface of an external contact of a given electronic part as represented by a wiring board, an IC package, etc.
A typical lower surface contact type contact, as schematically shown in FIG. 7, includes an upwardly projecting contact portion 3 which is brought into contact, under pressure, with a lower surface of an external contact 2 of a given electronic part 1 . In order to displace the contact portion 3 resiliently downward, the contact portion 3 is supported by a sidewardly expanding curved spring portion 4 .
The external contact 2 of the electronic part 1 is placed on the contact portion 3 to press the contact portion 3 downward, so that the curved spring portion 4 is compressed and the contact portion 3 is displaced downward. The restoring force of the curved spring portion 4 causes the contact portion 3 to contact, under pressure, the lower surface of the external contact 2 .
The curved spring portion 4 is displaced downward when it is pressed downward by the external contact 2 . The curved spring portion 4 naturally includes a downward displacement component F 1 and a rightward displacement component F 2 . Therefore, the curved spring portion 4 is actually moved in a combined direction F 3 of the components F 1 and F 2 .
This directly reflects on the movement of the contact portion 3 . Specifically, the contact portion 3 moves slantwise downward in the combined direction F 3 from a contact start point P 1 with respect to the external contact 2 and reaches a contact terminal point P 2 . As a consequence, a rightward escape (a movement) amount W is inevitably produced between the contact start point P 1 of the contact portion 3 and the contact terminal point P 2 .
This escape amount W causes the contact portion 3 to slide on the lower surface of the external contact 2 . In the case where the width of the external contact 2 is small, it gives rise to a problem that the contact portion 3 escapes from the lower surface of the external contact 2 . This problem becomes increasingly serious as the external contact is arranged at a smaller pitch. Therefore, a countermeasure is demanded.
The present invention has been accomplished in order to obviate the above problem.
SUMMARY OF THE INVENTION
It is, therefore, a general object of the present invention to provide a lower surface contact type contact capable of obviating the problem inherent in the conventional comparable device.
It is a specific object of the present invention to provide a lower surface contact type contact in which a contact portion is assuredly moved in a vertical direction as much as possible, thereby ensuring a reliable contact relation. Owing to this arrangement, the lower surface contact type contact according to the present invention can effectively cope with the requirement for arranging the external contact at a smaller pitch.
In order to achieve the above object, there is essentially provided a lower surface contact type contact which is to be arranged in array on a connector body made of an insulative material, comprising an upwardly projecting contact portion on which a lower surface of an external contact of an electronic part is placed to press the upward projecting contact portion downward; a leftwardly expanding curved spring portion including a downward displacement component for allowing a downward displacement of the contact portion when the contact portion is pressed downward by the external contact and a rightward displacement component for causing a tendency for rightward displacement of said contact portion; and a support post implanted in the connector body and adapted to support the curved spring portion, the support post being displaced leftward when the contact portion is displaced downward, so as to offset the tendency for rightward displacement.
The support post may be provided on a lower end thereof with a surface mounting terminal element projecting outward from the connector body.
A swing-preventive element may extend downward from a continuous portion between the contact portion and the curved spring portion, so that abutment between lower end of the swing-preventive element and the connector body prevents the contact portion from swinging or twisting.
Preferably, a left side surface of the contact portion is caused to contact, under pressure, with the connector body by resilient force of the curved spring portion.
A more complete application of the invention and many of the attendant advantages thereof will be readily obtained as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a front view of a lower surface contact type contact according to one embodiment of the present invention, in which motion of the lower surface contact type contact is indicated by a broken line;
FIG. 2 is a right side view of the lower surface contact type contact of FIG. 1;
FIG. 3 is a sectional view of the above lower surface contact type contact implanted in a connector body;
FIGS. 4A through 4D are sectional views showing the sequential steps of motion of the above lower surface contact type contact;
FIG. 5 is is a front view of a connector in which the above lower surface contact type contact is implanted;
FIG. 6 is a right side view of FIG. 5; and
FIG. 7 is a front view schematically showing the motion of a conventional lower surface contact type contact.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIGS. 1 through 6 show a lower surface contact type contact according to one preferred embodiment of the present invention.
This lower surface contact type contact includes an upwardly projecting contact portion 3 on which a lower surface of an external contact 2 of a given electronic part 1 is placed so as to press it downward. It further includes a leftwardly expanded curved spring portion 4 . The contact portion 3 is supported by this curved spring portion 4 . In other words, the contact portion 3 is continuous with one end of the curved spring portion 4 .
The curved spring portion 4 includes a downward displacement component F 1 for allowing a downward displacement of the contact portion 3 when it is pressed by the external contact 2 , and a rightward displacement component F 2 for allowing a rightward displacement of the contact portion 3 .
The curved spring portion 4 is supported by a support post 5 which is displaced leftward when the contact portion 3 is displaced downward, such that the rightward displacement component F 2 of the curved spring portion 4 is offset by the leftward displacement component F 4 of the support post 5 . Thus, the contact portion 3 is lowered generally vertically while maintaining its contacting position with respect to the external contact 2 at a contact start point P 1 .
That is, the contact portion 3 is continuous with one end of the curved spring portion 4 , and the support post 5 for displacing the curved spring portion 4 leftward is continuous with the other end.
The support post 5 extends generally linearly in an up and down direction. The support post 5 is provided at a lower end portion thereof with a press-fit claw 6 . The support post 5 is implanted in a connector body 7 through the press-fit claw 6 . The support post 5 includes a surface mounting terminal element 8 extending downward from the implanting portion and projecting outward from a lower surface of the connector body 7 .
For example, a rigid seat 14 is formed on a lower end of the support post 5 and the press-fit claw 6 projects leftward from a side surface of the seat 14 . The press-fit claw 6 is press fitted in a press-fit hole 15 formed in a side surface of a bottom wall of a contact receiving space 9 . By doing so, the whole lower surface contact type contact is supportingly implanted.
The support post and the curved spring portion 4 are received in the contact receiving space 9 formed on an upper part of the implanting portion. The contact portion 3 projects outward from an upper surface of the connector body 7 through an upper opening 10 of the contact receiving space 9 so as to be subjected to contact with the external contact 2 of the electronic part 1 .
The curved spring portion 4 includes a connecting arm 11 extending generally linearly in an up and down direction along the continuous portion between the curved spring portion 4 and the support post 5 . The curved spring portion 4 is continuous with an upper end of the support post 5 through the connecting arm 11 .
The connecting arm 11 and the upper end extending portion of the support post 5 extend in parallel relation with a small space 12 therebetween, thereby forming an inverted U-shaped hairpin-like spring portion 13 . This hairpin-like spring portion 13 projects upward beyond the center O of the curved spring portion 4 . In other words, the upper end of the support post 5 extends in such a manner as to project upward beyond the center O. The space 12 facilitates the leftward displacement of the support post 5 and the leftward displacement of the curved spring portion 4 .
A swing-preventive element 16 extends. downward from the continuous portion between the contact portion 3 and the curved spring portion 4 so that a lower end of the swing-preventive element 16 is brought into abutment with the connector body 7 (i.e., the inner wall surface of the contact receiving space 9 ). This arrangement serves to prevent the contact portion 3 from swinging or twisting. The longer the extending length dimension of the swing-preventive element 16 is, the greater the effect of swing prevention is. The swing-preventive element 16 and the contact portion 3 are in mutually oppositely directed relation and of a rigid structure.
As shown in FIG. 3, the left side surface of the contact portion 3 is caused to contact the connector body 7 by the resilient force of the curved spring portion 4 . That is, the left side surface of the contact portion 3 is caused to contact an end face of a top wall 17 by the resilient force of the curved spring portion 4 .
The position of the contact portion 3 indicated by a dotted line of FIG. 3 is a normal position before it is implanted (i.e., at the time of blanking operation). During the implanting operation, the contact portion 3 is displaced rightward against the resilient force of the curved spring portion 4 and the left side surface of the contact portion 3 is brought into contact, under pressure, with the end face of the top wall 17 by a restoring force of the curved spring portion 4 .
The whole lower surface contact type contact is formed by blanking a band plate so that it has the above construction and form. It is not necessary to subject the lower surface contact type contact to bending treatment. Accordingly, the obtained contact exhibits, as shown in FIG. 2, the form of a single plate when viewed in a direction of its right side. A front side surface of each contact element is present in a common plane and a rear side surface of each contact element is present in a common plane. Accordingly, both the front and rear side surfaces are present in mutually parallel common planes.
As shown in FIGS. 5 and 6, the connector body 7 includes a plurality of contact receiving spaces 9 arranged in array in a back and forth direction. The respective lower surface contact type contacts are arranged in array in the corresponding contact receiving spaces 9 .
The surface mounting terminal element 8 of the lower surface contact type contact is attached, in superposed relation, to an electrode pad on the surface of a wiring board 18 by soldering paste or the like. By doing so, the lower surface contact type contact is connected to the wiring board 18 .
With reference to FIGS. 4A-D, operation of the lower surface contact type contact will be described so that its construction will become more manifest.
As shown in FIGS. 4A and 4B, the electronic part 1 such as a wiring board is placed on the contact portion 3 through a lower surface of the external contact 2 .
Then, as shown in FIGS. 4C and 4D, the electronic part 1 is pressed downward so that the contact portion 3 is pressed downward by the external contact 2 . This downward pressing operation causes the curved spring portion 4 to be compressed and also causes the support post 5 (i.e., the hairpin-like spring portion 13 ) to be displaced leftward. This leftward displacement of the support post 5 causes the curved spring portion 4 to be displaced leftward together with the contact portion 3 , thereby offsetting the rightward displacement component F 2 of the curved spring portion 4 .
As previously described, the curved spring portion 4 includes the downward displacement component F 1 and the rightward displacement component F 2 and is displaced slantwise downward by the combined compositions. As a consequence, an escape amount W is produced. The rightward displacement component F 2 , as a cause for producing the escape amount W, of the curved spring portion 4 is offset by the leftward displacement component F 4 of the support post 5 and hairpin-like spring portion 13 , so that the contact portion 3 is displaced vertically as much as possible.
Thus, the contact portion 3 and the external contact 2 are displaced downward generally vertically while maintaining their relative contact positions. That is, they reach the contact terminal point P 2 while maintaining the contact start point P 1 .
The present invention can effectively obviate the problem inherent in the conventional lower surface contact type contact which problem (i.e., the escape amount W is produced to allow the contact portion to escape from the external contact) is created by the curved spring, thereby ensuring the contact portion to move generally vertically as much as possible. By doing so, a reliable contact relation is ensured. Therefore, the lower surface contact type contact according to the present invention can effectively cope with the requirement for arranging the external contact at a smaller pitch.
It is to be understood that the form of the invention herewith shown and described is to be taken as the preferred embodiment of the same, and that various changes in the shape, size and arrangement of parts may be resorted to without departing from the spirit of the invention or the scope of the appended claims. | A lower surface contact type contact which is to be arranged in array on a connector body made of an insulative material, comprising an upwardly projecting contact portion on which a lower surface of an external contact of an electronic part is placed to press the upward projecting contact portion downward; a leftwardly expanding curved spring portion including a downward displacement component for allowing a downward displacement of the contact portion when the contact portion is pressed downward by the external contact and a rightward displacement component for causing a tendency for rightward displacement of said contact portion; and a support post implanted in the connector body and adapted to support the curved spring portion, the support post being displaced leftward when the contact portion is displaced downward, so as to offset the tendenct for rightward displacement. | 7 |
BACKGROUND OF THE INVENTION
This invention relates generally to fuel supplying or dispensing apparatus, and more particularly to a fuel supplying apparatus capable of preventing an accident in which the fuel is sprayed around before the ejection pipe is inserted inside the fuel intake opening due to valve opening operation error, by the operation of the automatic valve closing mechanism.
Generally, in a known fuel supplying apparatus, the fuel supply is started by pulling the nozzle lever after the fuel supplying nozzle is inserted inside the fuel intake opening of the vehicle, and the supply of fuel is stopped by releasing the nozzle lever when the supplied fuel reaches a predetermined quantity.
Hence, in the conventional fuel supplying apparatus, organized, for example, so that the fuel supplying pump driving motor is driven automatically when the fuel supply nozzle is unhooked from the nozzle hanger provided at the side part of the main body of the fuel supplying apparatus, when the valve of the fuel supplying nozzle is opened by mistake before the ejection pipe is inserted inside the fuel intake opening of a vehicle and the like, large quantity of fuel is sprayed around within the fuel supplying station, and was disadvantageous in that the apparatus was quite dangerous when operated incorrectly.
As opposed to this, a fuel supplying apparatus has been proposed in which a solenoid valve is provided directly on the fluid supply passage inside the fuel supplying nozzle, to automatically stop the supply of fuel without the operation of the nozzle lever by closing the solenoid valve by the control signal applied from the apparatus for supplying fluid of predetermined quantity when the supply of fuel reaches a predetermined quantity.
However, this type of fuel supplying apparatus having automatic fuel supply stopping function, must all open or close the solenoid valve against the fluid pressure or the spring force and the like, and require a large current to operate the solenoid valve, thus being disadvantageous in that the electrical power consumption of the apparatus is large and uneconomical.
SUMMARY OF THE INVENTION
Accordingly, it is a general object of the present invention to provide a novel and useful fuel supplying apparatus which has solved the above described problems.
Another and more specific object of the invention is to provide a fuel supplying apparatus in which a solenoid valve is organized to conduct and open when an ejection pipe of a fuel supplying nozzle is inserted inside a fuel intake opening, by providing a type of solenoid valve which opens upon being supplied with current in an atmosphere introducing tube of an automatic valve closing mechanism comprising a diaphragm membrane which undergoes displacement by a negative pressure. By the apparatus of the present invention, even upon a situation, for example, in which the opening and closing valve is opened by mistake before the insertion of the ejection pipe inside the fuel intake opening, when fuel flows into a negative pressure generating part, irrespective of how small the fluid quantity is, the fuel is drawn out from within the negative pressure pipe by suction. Accordingly, the pressure inside a diaphragm chamber instantly becomes of negative pressure, and the opening and closing valve is closed immediately, thus positively preventing beforehand an accident in which the fuel is sprayed around outside the fuel intake opening.
Still another object of the invention is to provide a fuel supplying apparatus which positively prevents the overflowing of the fuel from the fuel intake opening due to the oversupplying of the fuel. According to the apparatus of the invention, upon supply of fuel to the full capacity of the tank, for example, the supply of fuel is stopped automatically when the pressure inside the diaphragm chamber becomes of negative pressure by the interruption of an open part of the atmosphere introducing tube by the fluid surface of the fuel.
Another object of the invention is to provide a fuel supplying apparatus having a high safety factor organized so that, in case of a power failure accident, the solenoid valve closes automatically to stop the supply of fuel.
Still another object of the invention is to provide a fuel supplying apparatus in which the solenoid valve is closed when the supplying quantity of fuel reaches a predetermined quantity by cutting off applying of current to the solenoid to put a negative pressure on the diaphragm membrane. According to the provision of the invention, the opening and closing valve can be closed automatically, and the opening and closing valve can be opened and closed and controlled by small electric current, as compared to an apparatus in which the opening and closing solenoid valve is provided directly in the passage of the fuel supplying nozzle.
Another object of the invention is to provide a fuel supplying apparatus in which a reed switch provided at the ejection pipe of the fuel supplying nozzle as an ejection pipe insertion detection switch, and this reed switch is operated by a magnet provided on a slider, when the slider provided at the ejection pipe moves to a predetermined position by the insertion operation of the ejection pipe into the fuel intake opening. According to the apparatus of the invention, the insertion of the ejection pipe inside the fuel intake opening can be detected positively and simply, and has a broad application field since the nozzle can be applied to either a suspending type or ground type fuel supplying apparatus.
Other objects and further features of the present invention will be apparent from the following detailed description with respect to preferred embodiments of the invention when read in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a view showing a general construction of an embodiment of a suspending type fuel supplying apparatus capable of supplying fuel fluid of predetermined quantity applied with a fuel supplying apparatus of the present invention;
FIG. 2 is a cross-sectional view of an embodiment of a fuel supplying nozzle of the apparatus of FIG. 1;
FIG. 3 is a cross-sectional view of the fuel supplying nozzle of FIG. 2 taken along the lines III--III;
FIG. 4 is an enlarged cross-sectional view of an embodiment of a solenoid valve part of the fuel supplying nozzle of FIG. 2;
FIG. 5 is a cross-sectional view of a modification of the solenoid valve part shown in FIG. 4;
FIG. 6 is a cross-sectional view of another modification of the solenoid valve part shown in FIG. 4; and
FIG. 7 is a view showing a general construction of an embodiment of a round type fuel supplying apparatus applied with a fuel supplying apparatus of the present invention.
DETAILED DESCRIPTION
In FIG. 1, a fuel supplying apparatus 11 comprises a delivery unit 12 attached to the roof of the fuel supplying station, and constructed so that a fuel supplying hose 14 is rolled around a hose reel 13 inside the delivery unit 12. A fuel supplying nozzle 15 provided at the end part of the hose 14 is inserted inside a fuel intake opening 16a of the vehicle to supply the fuel. The fuel supplying hose 14 inside the delivery unit 12 is connected to a fuel supplying pump 18 through a fixed pipe arrangement 17. The fuel pumped up from an underground tank 19 by the pump 18 is supplied to the delivery unit 12 through the fixed pipe arrangement 17 after passing through a flowmeter 20, and supplied to the nozzle 15 through the hose 14. The flow quantity of the fuel supplied through the nozzle 15 is measured by the flowmeter 20, and displayed by a supplied fuel quantity displaying device 21 provided at a position easily seen near the roof part of the fuel supplying station.
An opening and closing valve 23 and an automatic valve 25 opened and closed by the operation of a nozzle lever 22 and closed by a control signal, are provided inside a casing of the fuel supplying nozzle 15 as shown in FIG. 2. The valve 23 comprises a pair of main and sub valve bodies 26 and 27, and both valve bodies 26 and 27 are urged in the valve closing direction by a spring 27a. The displacing movement of the nozzle lever 22 is transmitted to the valve bodies 26 and 27, by a shaft 29 and a valve shaft 30 at a bottom comprising intermediate space, inserted freely slidable inside a sleeve 28. The valve shaft 30 has its bottom part inserted freely slidable inside the shaft 29, and a compressed spring 30a is provided under pressure between the bottom edge part of the valve shaft 30 and the bottom part of the shaft 29. In a state shown in FIGS. 2 and 3, two rollers 31 and 32 used as locking parts, are engaged to the valve shaft 30, and thus the valve shaft 30 and the shaft 29 undergo displacement unitarily.
The rollers 31 and 32 are respectively supported of their ends by a receiving plate 33, and is freely movable in the moving direction of the shaft 29. The receiving plate 33 is fixed to a diaphragm membrane 34 as shown in FIG. 3, and diaphragm chamber 36 is partitioned by the diaphragm membrane 34 and a lid 35 provided outside the diaphragm membrane 34. A compressed spring 37 is provided under pressure inside the diaphragm chamber 36, and thus the rollers 31 and 32 are urged in an engaging direction with the valve shaft 30. When the engagement of the valve shaft 30 with the rollers 31 and 32 is disengaged, the valve shaft 30 becomes movable, separately with respect to the shaft 29. Regarding an example of the lock mechanism of the valve shaft 30, it is described in detail in the U.S. Pat. No. 3,638,689, for example.
One end of a negative pressure pipe 38 is opened at the internal periphery of a valve seat 38 of the automatic valve 25, and the valve seat itself becomes a Venturi tube part upon opening of the automatic valve 25, thus the air inside the negative pressure pipe 39 is drawn out under suction into the valve seat 38. The other end of the negative pressure pipe 39 is opened inside the diaphragm chamber 36. Furthermore, an atmosphere introducing tube 40 is provided inside an ejection pipe 24 of the fuel supplying nozzle 15, and one end of the atmosphere introducing tube 40 is opened as an atmosphere introducing opening at the front edge sidewall part of the ejection pipe 24. On the other hand, the other end of the atmosphere introducing tube 40 is connected to the diaphragm chamber 36 through a solenoid valve 41 provided between tubes 40a inside the fuel supplying nozzle 15.
As shown in FIG. 4, the solenoid valve 41 is screwed fixedly inside a space 42 formed half way between the atmosphere introducing tube 40. A solenoid 43 is partitioned from the space 42 by a diaphragm membrane 44, and a valve body 45 comprising a magnetic body fixed at the center part of the diaphragm membrane 44 separates from or makes contact with a valve seat 46, according to the magnetization or demagnetization state of the solenoid 43. The solenoid 43 is not conducting upon non-supplying of the fuel, and the valve body 45 makes contact with the valve seat 46 due to the elasticity of the diaphragm membrane 44 and the magnetic repellent force exerted by the solenoid 43. The solenoid valve 41 is then closed.
When the solenoid 43 is conducting and magnetized upon supplying of fuel, the valve body 45 is separated from the valve seat 46 by the magnetic attraction force of the solenoid 43 exerted against the elasticity of the diaphragm membrane 44.
In this embodiment of the present invention, the solenoid valve 41 is provided inside the atmosphere introducing tube 40, and an O-ring 24a is provided at the connection part between the ejection pipe 24 and the fuel supplying nozzle 15, thus preventing the short connection between the negative pressure tube 39 and the atmosphere introducing tube 40 by this O-ring 24a. In addition, when it is possible to provide the solenoid valve 41 in the up-stream side of the above O-ring 24a, this O-ring can be eliminated.
The opening and closing control of the solenoid valve 41 is, in this embodiment, performed by the signal emitted from a control part 47 for controlling the supply of fluid of predetermined quantity provided inside the fuel supplying station structure. This control part 47 is determined of its expected fuel supply quantity by a preset device 48 for presetting the predetermined quantity of fluid to be supplied, and generates a control signal when the supplied fuel quantity coincides with the predetermined fuel supply quantity. The preset device 48 is positioned outside near the fuel supply servicing area, and comprises a plurality of push buttons showing the corresponding fuel supply quantity on the front pannel.
An insertion detection switch 50 detects the insertion of the ejection pipe 24. In this embodiment of the invention, a reed switch is used as the insertion detection switch 50. The switch 50 is fixed on the inner wall near the front end part of the ejection pipe 24. An adapter 51 used as a slider which fixedly engages with the open part of the fuel supplying opening 26a upon supply of fuel, is inserted freely slidable on the outer wall near the front end part of the ejection pipe 24. By the compressed spring inserted between the joint base part of the ejection pipe 24 and the adapter 51, the adapter 51 is constantly urged in the front end side direction of the ejection pipe 24.
A magnet 53 is provided inside the adapter 51. The adapter 51 confronts the insertion detection switch 50 when the ejection pipe 24 is inserted inside the fuel supplying opening 16a for a length required for the supply of fuel. Then, the switch 50 is closed by the magnetic force produced by the magnet 53 provided inside the adapter 51. The switch 50 is connected to the control part 47, and the circuit is organized so that the solenoid valve 41 conducts and opens when the switch 50 closes. Upon non-supplying of fuel, the solenoid valve 41 is closed, and the fuel supplying apparatus is in a state possible for fuel supply only when the solenoid valve 41 is open, as will be described hereinafter.
First, the operation for supplying fuel to fill the tank full without the use of the preset device 48, will now be described.
Upon non-supplying of fuel, the fuel supplying nozzle 15 is positioned at the fuel supply waiting position so as not to be in the way of a vehicle 16, and by pulling on a suspended string 15a suspended from the fuel supplying nozzle 15, the fuel supplying nozzle 15 can be lowered to the fuel supplying position by rotating the hose reel 13. Upon pulling of the suspended string 15a, a fuel supplying pump driving motor 18a is started, and the fuel supplying pump 18 is driven.
The ejection pipe 24 of the fuel supplying nozzle 15 is inserted into the fuel supplying opening 16a of the vehicle 16. This insertion of the ejection pipe 34 is detected by the switch 50, and the solenoid valve 41 is opened by the closing signal of the switch 50.
If the ejection pipe 24 is not inserted inside the fuel intake opening 16a to a predetermined position, the fuel supplying apparatus does not go into a state possible for fuel supply since the solenoid valve 41 does not open. Therefore, as will be described later on, even when the nozzle lever 22 is pulled by mistake before the ejection pipe 24 is inserted inside the fuel intake opening 16a, fuel is not sprayed around outside from the fuel supplying nozzle 15.
When the ejection pipe 24 is inserted into the fuel intake opening 16a, the nozzle lever 22 is pulled up to the valve opening position shown by the dotted lines of FIG. 2, and held in that locked position. Upon pulling up of the nozzle lever 22, the shaft 29 pushes the valve shaft 30 in the upward direction, and thus the sub valve body 27 separates from the main valve body 26 in the upward direction. Hence, a flow passage 26a formed at the main valve body 26 opens, and the fuel flows out onto the automatic valve 25 side through the flow passage 26a. When the nozzle lever 22 is pulled up even further, the valve shaft 30 pushes the main valve body 26 in the upward direction, and thus the valve 23 is fully opened. Since the front and rear of the main valve body 26 are respectively communicated by a flow passage 26a before the main valve body 26 opens, the main valve body 26 can be opened by a small force.
The fuel which has passed through the valve 23 passes through the automatic valve 25, and is supplied inside the fuel supplying opening 16a from the ejection pipe 24.
By the Venturi effect introduced upon the passing of the fuel through the automatic valve 25, the air inside the negative pressure pipe 39 is drawn out by suction into the automatic valve 25.
Therefore, at the early stage of the starting of the fuel supply, one end of the atmosphere introducing tube 40 is open to the atmosphere not being interrupted by the fluid surface, and the amount of air drawn out from within the diaphragm chamber 36 by the negative pressure pipe 39 is replenished by the atmosphere introducing tube 40. For this reason, it never becomes of negative pressure inside the diaphragm chamber 36, and the disphragm membrane 34 does not undergo displacement. Accordingly, the rollers 31 and 32 are engaged to the valve shaft 30, fixing the valve shaft 30 in a immovable state with respect to the shaft 29, and hence the valve shaft 30 is locked in an open position.
When the fuel supply tank (not shown) of the vehicle 16 becomes full as the supplying of fuel progresses, the open part of the atmosphere introducing tube 40 of the ejection pipe 24 is interrupted by the fluid surface inside the fuel intake opening 16a. On the other hand, the air is continuously drawn out by suction by the negative pressure pipe 39, and thus it instantly becomes of negative pressure inside the diaphragm chamber 36, and hence the diaphragm membrane 34 undergoes displacement to the left-hand side direction in FIG. 3 against the compressed spring 37. As a result, the rollers 31 and 32 separate from the valve shaft 30 together with the displacement of the receiving plate 33, and hence the valve shaft 30 is moved downwards against the compressed spring 30a by the fluid pressure and the resilient restitution of the spring 27a exerted on the main valve body 26 and the sub valve body 27. Accordingly, the valve 23 close, and the supply of fluid is stopped automatically.
The operator then pulls the fuel supplying nozzle 15 from within the fuel intake opening 16a, and releases the nozzle lever 22 from its locked position to the valve closing position. Hence, the shaft 29 is pushed downwards by the compressed spring 30a, and the rollers 31 and 32 engages again with the valve shaft 30.
Upon supplying fuel to fill the tank full, the supplying of fuel is automatically stopped by the operation of the automatic valve closing mechanism when the atmosphere introducing opening of the atmosphere introducing tube 40 is interrupted by the fuel.
Next, the operation upon establishing of the fuel supply of predetermined quantity by the use of the preset device 48 will now be described.
First, before performing the fuel supplying operation, a push button key 49 of the preset device 48 which shows the desired fuel supplying quantity is pushed, to establish the desired fuel supplying quantity in the control part 47. This fuel supplying quantity is transmitted to the control part 47 and memorized therein. When the establishing of the fuel supplying quantity by the preset device 48 is completed, the fuel supplying nozzle 15 is inserted inside the fuel intake opening 16a of the vehicle 16.
When the nozzle lever 22 is pulled by mistake before the ejection pipe 24 is inserted inside the fuel intake opening 16a, the fuel supplied within the fuel supplying nozzle 15 flows in the direction of the automatic valve 25 through the valve 23. However, the solenoid valve 41 is not open, and thus the negative pressure pipe 39 and the atmosphere introducing tube 40 are not communicated. Accordingly, when the fuel flows through within the automatic valve 25, irrespective of how small the fluid quantity is, air is drawn out from the negative pressure tube 39 by suction, and the pressure inside the diaphragm chamber 36 immediately becomes of negative pressure. That is to say, the state inside the diaphragm chamber 36 becomes a state identical to that described earlier, in which the open part of the atmosphere introducing tube 40 is interrupted upon supply of fuel to the full capacity of the tank, and the valve 23 is closed immediately by the displacement of the diaphragm membrane 34 due to the negative pressure.
Hence, even when the nozzle lever 22 is pulled by mistake before the ejection pipe 24 is inserted inside the fuel supplying opening, the valve 23 once opened immediately closes, and there is no inconvenience like the spraying around of the fuel from the fuel supplying nozzle 15.
When the ejection pipe 24 is inserted inside the fuel intake opening 16a to a predetermined position, the solenoid valve 41 opens, and thus upon pulling of the nozzle lever 22 after the pulling of the nozzle lever by mistake, normal fuel supplying operation is started.
When the supply of fuel reaches a predetermined fuel supplying quantity as the fuel supplying progresses, the solenoid valve 41 is cut off its conduction by the signal from the control part 47, and hence the solenoid valve 41 closes. Resultingly, the negative pressure pipe 39 communicated with the atmosphere by the atmosphere introducing tube 40 until that point, becomes cut off its communication with the atmosphere, and the pressure inside the diaphragm chamber 36 becomes of negative pressure. Accordingly, as described above, the valve 23 is closed automatically along with the displacement of the diaphragm membrane 34.
As described above, when the fuel quantity to be supplied is specified, the solenoid valve 41 closes simultaneously as when the supply of fuel reaches a predetermined fuel supply quantity. Accordingly, the supply of fuel is automatically stopped as the diaphragm membrane 34 is displaced by the suction due to the negative pressure. This displacement of the diaphragm membrane 34 is a mechanical displacement in which the negative pressure is used, and thus a large current is not required to open and close the solenoid valve 41, resulting in a very small electrical power consumption of the solenoid valve 41.
Moreover, even in a situation in which the control part 47 becomes inoperable due to a power failure accident, the solenoid valve 41 is cut off its conduction simultaneously as the power failure occurrence, automatically closing the solenoid valve 41, and hence inconveniences such as the continuation of the supplying of fuel in a non-controlled state is not introduced.
In the above embodiment of the invention, besides the construction of the solenoid valve shown in FIG. 4, for example, the valve seat 46 can be formed from a magnetic material, and by fixing a magnet onto the valve body 45, the valve body 45 can constantly be positioned on the valve seat 46 by the magnetic force of the magnet, and organized so that upon starting of the supply of fuel, the valve body 45 is separated from the valve seat 46 by a magnetic force greater than the magnetic force generated when the solenoid 43 conducts. The solenoid valve can also be constructed as a solenoid valve 61 shown in FIG. 5, in which a spring 62 urges a valve body 63. In addition, the solenoid valve can use a spherical shape valve body 65 shown in a solenoid valve 64 of FIG. 6 instead of the flat plate valve body.
Furthermore, in the above embodiment of the invention, the suspending type fuel supplying apparatus was used as an example of the fuel supplying apparatus, but the invention can also be applied to a ground type fuel supplying apparatus 71 shown in FIG. 7. In this embodiment of the invention, when a fuel supplying nozzle 72 is unhooked from a nozzle hanger 73 provided at the side of the fuel supplying apparatus 71, the apparatus is set in an operational state by starting of a fuel supplying pump driving motor 74.
Furthermore, in each of the above embodiments, the insertion detection switch is not limited to a reed switch provided at the ejection pipe 24, and can be, for example, a piezo-electric switch, a capacitive switch, or a photoelectric switch provided at the adapter 51. Moreover, the attaching position of these switches is not limited at the ejection pipe 24 or the adapter 51, and other attaching positions can be selected.
In each of the above embodiments, the automatic valve closing mechanism is constructed so that by respectively displacing the valve shaft 30 with respect to the shaft 29, the nozzle lever 22 closes the valve 23 although the nozzle lever 22 is in a valve opening position. However, for example, a fuel supplying nozzle which is capable of moving the fulcrum of the nozzle lever 22 can be used, and an automatic valve closing mechanism provided at the fulcrum part of the nozzle lever 22, to move the fulcrum of the nozzle lever 22 to the position which closes the valve 23 by the operation of the automatic valve closing mechanism, holding the rear end part of the nozzle lever 22 at the valve opening position.
Further, this invention is not limited to these embodiments. Variations and modifications may be made without departing from the scope of the invention. | A fuel supplying apparatus comprises a fuel supplying nozzle having an ejection pipe for ejecting fuel and a supplying passage for supplying the fuel to the ejection pipe, an opening and closing valve provided in the supply passage, a nozzle lever for opening the opening and closing valve, locking mechanism for locking the opening and closing valve in an open state, negative pressure generating mechanism for generating negative pressure upon supply of the fuel outside through the ejection pipe, lock releasing mechanism for releasing the lock of the locking mechanism by the introduction of the negative pressure generated by the negative pressure generating mechanism, atmosphere introducing mechanism for introducing atmosphere into the lock releasing mechanism to neutralize the negative pressure, solenoid valve for interrupting the introduction of the atmosphere by the atmosphere introducing mechanism when no current is introduced, and allowing the introduction of the atmosphere by the atmosphere introducing mechanism when introduced with current, and detection and current applying switch for detecting the insertion of the ejection pipe inside a fuel intake opening of a vehicle and the like and introduces current to the solenoid valve. | 8 |
More than one reissue application has been filed for the reissue of U.S. Pat. No. 7,372,614. This application is a reissue continuation of application Ser. No. 12/764,557 (now U.S. Pat. No. Re. 45,511 issued May 12, 2015), which is an application for reissue of U.S. Pat. No. 7,372,614. Co-pending application Ser. No. 14/663,327 is a reissue divisional of application Ser. No. 12/764,557, which is an application for reissue of U.S. Pat. No. 7,372,614.
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a divisional of U.S. application Ser. No. 10/629,798, filed Jul. 30, 2003, now U.S. Pat. No. 7,224,504, which is incorporated by reference herein in its entirety.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention is related to deformable optical devices.
2. Background Art
Light passing through an optical system can become distorted for various reasons. A lens, mirror, coatings thereon, or other devices in the optical system can: have imperfections, contaminants, or defects on their surface or within their structure. These together with thermal and other environmental factors including the ambient properties are sources of error in the light beam. Wavefront aberrations can lead to substantial degrading of the operation of an apparatus having the optical system.
For example, in photolithography where the state of the art requires nanometer level resolution, even small wavefront aberrations in the light beam can cause substantial errors in patterned devices. If these errors are outside of a tolerance budget, the devices will fail. Thus, optical elements within the photolithography systems must be manufactured to exacting tolerances and their environment tightly controlled.
Since practical limits exist in manufacturing tolerances and environmental control, some optical systems use deformable optics, such as deformable mirrors, to help compensate for wavefront aberrations. The deformable mirrors normally include an array of discrete actuators coupled between the mirror and a support. A measuring device (e.g., inline or offline) measures, either continuously or at the beginning of a cycle, the wavefront aberrations at one or more sections of the optical system. A control signal is then generated and transmitted to the actuators, which individually move an area of the deformable optic. The wavefront of the light beam reflecting from the deformed surface is adjusted to compensate for the aberration, and produce a substantially ideal wavefront.
One problem with the conventional deformable optics is that they use rather large actuators to move the optic. Based on the actuator's size and the size of the deformable optic, only a certain number of actuators (e.g., a certain density of actuators) can be coupled to the deformable optic, which limits the amount of fine correction. Density also directly correlates to the type of aberration that can be corrected, i.e., a lower density only allows for correction of lower order (e.g. lower spatial frequency) aberrations. Typical deformable optics can correct for only low order aberrations based on their low actuator density. However, sometimes higher order (e.g. higher spatial frequency) aberrations are necessary to correct. For example, sometimes wavefront aberrations are characterized using Standard Zernike polynomials, including higher orders. Conventional actuator densities cannot adequately correct for higher order terms.
Therefore, a deformable optic is needed that can correct for higher order terms of wavefront aberrations in an optical system.
BRIEF SUMMARY OF THE INVENTION
Embodiments of the present invention provide a deformable optical system. The deformable optical system includes a reflection device having a first reflecting surface and a second surface and an integrated circuit actuator having a support device and moveable extensions extending from the support surface and coupled to the second surface. Electrodes are individually coupled to corresponding ones of the extensions. A controller is coupled to the electrodes and is configured to control the extensions via the electrodes.
Other embodiments of the present invention provide a deformable optical device. The deformable optical device includes a reflection device having a first reflecting surface and a second surface, an integrated circuit actuator having a support device and moveable extensions extending therefrom, which are coupled to the second surface, and electrodes coupled to corresponding ones of the extensions.
Still other embodiments of the present invention provide a method. The method includes detecting a wavefront aberration, generating a control signal based on the detected aberration, moving extensions of a integrated circuit piezoelectric actuator based on the control signal, and deforming a reflector based on the moving of the extensions to correct the aberrations in the wavefront.
Further embodiments, features, and advantages of the present inventions, as well as the structure and operation of the various embodiments of the present invention, are described in detail below with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS/FIGURES
The accompanying drawings, which are incorporated herein and form part of the specification, illustrate the present invention and, together with the description, further serve to explain the principles of the invention and to enable a person skilled in the relevant art(s) to make and use the invention.
FIG. 1 is a deformable optic system according to an embodiment of the present invention.
FIG. 2 is a deformable optic system according to another embodiment of the present invention.
FIG. 3 shows an exemplary actuator extension configuration according to embodiments of the present invention.
The present invention is described with reference to the accompanying drawings. In the drawings, like reference numbers can indicate identical or functionally similar elements. Additionally, the leftmost digit of a reference number usually identifies the drawing in which the reference number first appears.
DETAILED DESCRIPTION OF THE INVENTION
Overview
While specific configurations and arrangements are discussed, it should be understood that this is done for illustrative purposes only. A person skilled in the pertinent art will recognize that other configurations and arrangements can be used without departing from the spirit and scope of the present invention. It will be apparent to a person skilled in the pertinent art that this invention can also be employed in a variety of other applications.
Embodiments of the present invention provide a deformable optical device having a reflective device coupled to an integrated circuit actuator including a support device and moveable extensions formed thereon. The integrated circuit actuator has a very high density of extensions (e.g., actuation devices), which can be formed in any pattern desired.
The high density of actuators is possibly because of using integrated circuit technology to manufacture the actuator. For example, the extensions can be on a micron scale and related density, which was not possible in conventional actuators. Larger scale (e.g. millimeter scale) extensions and related density are possible also; therefore the use of integrated circuit technology is applicable both within and outside of the realm of conventional actuators. Furthermore, the scale of extensions and related density are only limited by the state of the art of integrated circuit technology and thus sub-micron level scales are also possible. Having the high density of extensions allows the integrated circuit actuator to individually (or in small groups to) deform very small (e.g., micron level) areas of the reflective device, producing a very fine tunable deformation. This, in turn, allows the deformable mirror to correct for high order aberrations in a wavefront as well as low order.
For example, an integrated circuit piezoelectric actuator having a very high number of piezoelectric pins on a micron scale that extend from a support can be formed, for example using lithography techniques. Each pin on the actuator can be individually coupled through individual control lines to a controller. The pins are coupled to small areas of the reflective optic, so that very fine adjustments can be made to the reflective surface of the reflective optic. In one embodiment, there can be up to about 1 million actuators per square millimeter, which is much denser than conventional systems by several orders of magnitude. For example, U.S. Pat. No. 4,944,580 to MacDonald et. al.shows a conventional actuator element being about 0.2-0.3 inches on a side (e.g., 5 mm on a side), which is about 0.04 per square millimeter. It is to be appreciated that even more actuators may be manufactured per square millimeter as technology advances, as would be obvious to one of ordinary skill in the art. This is also contemplated within the scope of the present invention.
Further, using integrated circuit technology to manufacture the actuator elements allows for a substantial decrease in overall cost and a substantial increase in the complexity of patterns that the actuator elements can be formed in to interact with the deformable optic.
Planar Actuator and Reflective Device
FIG. 1 shows a system 100 according to embodiments of the present invention. One example of system 100 is a deformable optics system. System 100 includes a deformable optics device 102 coupled to a control system 104 . Optionally, a measuring system 106 can also be coupled to the control system 104 . Measuring system 106 can be used to detect a wavefront of light passing through system 100 to determine wavefront aberrations. Controller 104 can then calculate compensation values, and control signals based thereon can be used to control deformable optics device 102 .
For example, light passing through an optical system and/or a reticle in a lithography system can be measured (either offline or online), using measuring system 106 , to detect wavefront aberrations. A compensation value can be calculated, which is used to generate control signals transmitted from control system 104 to deformable optics device 102 . Then, before the light is projected onto a substrate for patterning, the light is reflected from deformable optics device 102 . Thus, the patterning light is substantially corrected of aberrations, greatly improving the performance of a patterned device.
Deformable optics device 102 includes a reflective device 110 (e.g., a mirror), an integrated circuit actuator 112 (e.g., an integrated circuit set of piezoelectric actuators), and electrodes 114 . Reflective device 110 includes a first reflective surface 116 and a second surface 118 . Actuator 112 includes a support device 120 (e.g., a piezoelectric chuck, or the like) with extensions 122 (e.g., moveable extensions, such as piezoelectric pins, strips, concentric rings, or other shapes) extending therefrom. Extensions 122 can be formed on support device 120 via lithography methods, or the like, and can be on a micron scale (or any scale within the realm of integrated circuit technology). In various embodiments, extensions 122 can be formed from lead zirconate titanate (PZT), zinc oxide (ZO), polyvinylidene fluoride (PVDF) polymer films, and the like (hereinafter, the term piezoelectric and all possible piezoelectric materials, for example PZT, ZO, PVDF, and the like, will be referred to as “PZT”).
An optional second support device 124 could be used to support electrodes 114 . Second support device 124 can include a connection circuit (not shown) coupling controller 104 to electrodes 114 . Also, second support device 124 can be coupled to optional mounting balls 126 (e.g., a ball grid array). In some embodiments, support device 120 can have a conductive (e.g., nickel (Ni)) plated surface 128 . Also, in some embodiments, electrodes 114 can be conductivly (e.g, Ni) plated.
Using integrated circuit PZT technology for actuator 112 allows for each individual actuator 122 (e.g., PZT pin) to be substantially smaller compared to conventional discrete actuators. For example, PZT pins 122 can be between about 1 to about 10 microns in width or diameter, depending on their shape. This can result in a very high density of PZT pins 122 , which provides high resolution and improved wavelength correction. For example, integrated circuit PZT technology can allow for correction capability of one or a combination of Standard Zernike higher order polynomial terms with very little residual error. Also, by using the integrated circuit PZT technique, high density can be achieved for virtually any pattern of PZT pins 122 .
Using piezoelectric technology allows for monitoring of movement of each individual PZT pin 122 and each small area of reflective surface 116 controlled by each PZT pin 122 . This is because each PZT pin 122 acts as a capacitance. A change in capacitance of PZT pins 122 can be monitored, which indicates whether each individual PZT pin 122 has expanded and/or contracted. Thus, system 100 can be used to verify movement of reflective surface 116 based on verifying movement of PZT pin 122 . In some cases, a value of change of capacitance can be equated to an actual distance moved of each PZT pin 122 , which can also be monitored.
A channel depth between each PZT pin 122 (e.g., height of each PZT pin 122 ) can be adjusted during formation based on a desired amount of decoupling between PZT pins 122 that is desired. For example, if some parts of reflective surface 116 are best moved as larger sections, while other parts are best moved as smaller sections, a height of PZT pins in the various areas can be formed to reflect this. The less height, the less decoupled, i.e., the more adjacent PZT pins 122 are affected by adjacent pins. In contrast, the more height, the more decoupled, i.e., very fine-tuning of reflective surface 116 can result with very tall PZT pins 122 .
Using integrated circuit PZT technology further allows for formation of PZT pins 122 having variable spatial density (e.g., a radial axis) and variable spatial patterns (radial, Cartesian, asymmetric, etc.). This can lead to ever better wavefront correction, particularly for higher order Zernike terms.
Curved Actuator and Deformable Optic Device
It is to be appreciated that deformable optics device 102 can be of any shape, and not just planar, as would be known to a skilled artisan.
For example, as shown in FIG. 2 , a curved (e.g., an aspherical, etc.) deformable optics device 202 can be used in a system 200 according to embodiments of the present invention. Deformable optics device 202 can be coupled to a control system 204 , which can be coupled to a measuring system 206 , as described above.
Deformable optics device 202 includes a reflective device 210 (e.g., a mirror), an actuator 212 (e.g., an integrated circuit set of piezoelectric (PZT) actuators), and electrodes 214 . Reflective device 210 includes a first reflective surface 216 and a second surface 218 . Actuator 212 includes a support device 220 (e.g., a PZT chuck, or the like) and extensions 222 (e.g., moveable extensions, such as PZT pins) extending therefrom. Extensions 222 can be formed on support device 220 via lithography methods, or the like.
An optional second support device 224 could be used to support electrodes 214 . Second support device 224 can include a connection circuit coupled controller 204 to electrodes 214 . Also, second support device 224 can be coupled to optional mounting balls 126 . In some embodiments, support device 220 can have a nickel (Ni) plated surface 228 . Also, in some embodiments, electrodes 214 can be Ni plated.
Example Actuator Extension Configuration
FIG. 3 shows an exemplary actuator extension configuration 300 according to embodiments of the present invention. Each asterisk 302 is located where an actuator element will interact with a deformable optic (e.g., 102 or 202 ). This pattern includes a variable density (e.g., spacing) and complex radial concentric pattern. This is accomplished using the integrated circuit actuators, which allows for variable density. Also, all actuators can fall in a predefined plane (e.g., flat, curved, etc.) because of using integrated circuit manufacturing technology. This type of pattern was not available in conventional systems because of their use of discrete actuators.
CONCLUSION
Example embodiments of the methods, circuits, and components of the present invention have been described herein. As noted elsewhere, these example embodiments have been described for illustrative purposes only, and are not limiting. Other embodiments are possible and are covered by the invention. Such embodiments will be apparent to persons skilled in the relevant art(s) based on the teachings contained herein. Thus, the breadth and scope of the present invention is should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims and their equivalents. | A deformable optical device includes a reflection device having a first reflecting surface and a second surface, an actuator (e.g., an integrated circuit piezoelectric actuator) having a support device and moveable extensions extending therefrom, which are coupled to the second surface, and electrodes coupled to corresponding ones of the extensions. Wavefront aberrations are detected and used to generate a control signal. The extensions are moved based on the control signal. The movement deforms the reflecting surface to correct the aberrations in the wavefront. | 8 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to an avalanche photodiode and, particularly, to an avalanche photodiode for optical communication.
2. Description of the Related Art
As avalanche multiplication type semiconductor light-receiving elements for optical communication, elements using InGaAs lattice-matching with InP in the light-absorbing layer are widely used (see, for example, Hirho Yonetsu, “Optical Communication Element Engineering” Kogaku Tosho (K.K.)). In this avalanche photodiode (APD), either carrier of an electron-hole pair generated in the light-absorbing layer is accelerated by an electric field and injected into the multiplication layer. A high electric field is applied to the multiplication layer, where these injected electrons or holes are accelerated more and eventually ionized. The characteristics of the APD allows its important noise characteristics to be decided by the ionizing process of carriers in this multiplication process.
Specifically, if the ratio (ratio of ionization rates) of the electrons to holes ionized in this multiplication layer is increased, the noise characteristics are expected to be improved. Here, although the ionization rate (α) of the electrons may be larger than the ionization rate (β) of the holes and vice versa, the ratio (α/βor β/α) of ionization rates is preferably larger. Also, with regard to high-speed response characteristics which are important characteristics similarly to the noise characteristics, the ratio of ionization rates has a large influence thereon. The high-speed response characteristics are decided by the time constant defined by element resistance and element capacity, the time required for carriers to pass through the absorption layer and multiplication layer and the ratio of ionization rates. To tell the relation to the ratio of ionization rates, a larger ratio of ionization rates brings about better high-speed response characteristics.
However, the ratio of ionization rates is decided depending on the type of material. When InP is used in the multiplication layer, the ionization rate of holes is large. However, the ratio (β/α) of the ionization rates is about 2 at most. Therefore, APDs using AlInAs having a high ratio of ionization rates in the multiplication layer are being developed.
If this AlInAs is used in the multiplication layer, the ionization rate of electrons can be increased (α>β) and an ionization rate of about 4 is obtained. Besides the above, researches and developments are made intensively to increase the ionization rate by making the multiplication layer have an AlInAs super lattice structure as reported in an article entitled “Planer Type Super Lattice APD” which is Isao Watanabe & 5 others, “Planer Type Super Lattice APD”, Shingaku Giho, LQE97-79, 1997-10, pp69–74.
However, when the multiplication in layers other than the multiplication layer is caused even if the ratio of ionization rates of the multiplication layer is improved, the ratio of ionization rates drops, causing deteriorations in noise characteristics and high-speed response characteristics. Particularly, in semiconductors having a narrow bandgap, multiplication is caused easily in a lower electric field. Therefore, multiplication takes place very easily in the case of InGaAs used for the light-absorbing layer in APDs for optical communication. When multiplication takes place in InGaAs whose ratio (α/β) of ionization rates is about 2, the ratio of ionization rates drops in APDs using InP which multiplies (β>α) holes for the multiplication layer.
Also, in the case of APDs using AlInAs which multiplies (α>β) electrons as in the case of InGaAs for the multiplication layer, the ratio of ionization rates drops because the ratio of ionization rates of AlInAs is about 4. For this, usual APDs are used in the situation where a high electric field is applied to the InGaAs absorbing layer, giving rise to the problem that noise characteristics are impaired. Moreover, supposing that a constant electric field is applied to the InGaAs absorbing layer, the multiplied carriers are increased and the ratio of ionization rates drops in the case of making the InGaAs absorbing layer thick. Therefore, in current APDs for communication, there is a tradeoff relation between sensitivity characteristics and noise characteristics and it is therefore difficult to attain the compatibility between sensitivity characteristics and noise characteristics.
Also, in high-speed response APDs, the running time of carriers generated in the depletion layer and the diffusion time of carriers generated in the non-depletion region largely affect high-speed response characteristics. As measures taken for this, there are, for example, methods in which the carrier density in an absorbing layer which is undepleted is changed to thereby control an internal electric field and the over-shooting speed of electrons are utilized to thereby shorten the diffusion time of carries as reported in Ning, Li, et. al. “InGaAs/InAlAs avalanche photo diode with undepleted absorber”, Appl. Phys. Lett: 31, Mar. 2003).
However, because, in the above structure, impurities are added to the InGaAs absorbing layer region to form the non-depletion region, it is necessary to make thin the absorbing layer to obtain an electric field higher enough to cause the over-shooting of electrons in the whole absorbing layer region. However, if the absorbing layer is made thin, the light to be transmitted is increased, posing the problem that the sensitivity which is important characteristics for APDs is deteriorated.
Also, a Publication of JP-A No. 2000-22197 discloses an avalanche photodiode in which the semiconductor light-absorbing layer is constituted of two layers consisting of a depletion region which is adjacent to the semiconductor field limiting layer and has a thickness of 10 nm or more and 0.3 μm or less and a non-depletion region which is also adjacent to the semiconductor field limiting layer and has a thickness of 2 μm or less.
However, when light is incident from the upper surface of the element in usual, the incident light is almost absorbed in the semiconductor absorbing layer which is to be undepleted because the light-absorbing layer to be depleted is thin. In this case, the electron-hole pairs generated in the absorbing layer almost constitute diffusion current and therefore, it takes considerable time to draw the diffusion current as signals, leading to a deterioration in high-speed response characteristics. Also, these electron-hole pairs are recombined in the non-depletion region before the diffusion current is drawn as signals, posing the problem that the diffused current is not drawn as signals, causing a deterioration in receiving sensitivity.
SUMMARY OF THE INVENTION
As mentioned above, avalanche photodiodes must be used under high voltage and it is demanded of these avalanche photodiodes to have high sensitivity, low-noise characteristics and high-speed response characteristics. If the absorbing layer is made thick to better sensitivity, this gives rise to the problem that carriers multiplied in the absorbing layer are increased, resulting in deteriorations in noise characteristics and high-speed response characteristics.
Also, the absorbing layer must be made thin to improve low-noise characteristics and high-speed response characteristics, giving rise to the problem that sensitivity characteristics are sacrificed.
In view of the above situation, it is an object of the present invention to provide an avalanche photodiode which can be improved in low-noise characteristics and high-speed response characteristics and can provide high sensitivity.
The above object is attained by an avalanche photodiode according to the present invention, the avalanche photodiode comprising a first conductive type semiconductor layer, a second conductive type semiconductor layer, a semiconductor multiplication layer interposed between the first conductive type semiconductor layer and the second conductive type semiconductor layer and a semiconductor light-absorbing layer interposed between the semiconductor multiplication layer and the second conductive type semiconductor layer, the avalanche photodiode further comprising a multiplication suppressing layer which suppresses the multiplication of the semiconductor light-absorbing layer and has a thickness of 0.6 μm or less between the semiconductor light-absorbing layer and the second conductive type semiconductor layer, wherein the thickness of the semiconductor light-absorbing layer is set to 0.5 μm or more.
In the present invention, impurities are added in a high concentration to a part of the light-absorbing layer to form a non-depletion region (a multiplication suppressing layer is inserted), whereby an avalanche photodiode can be attained which can be reduced in working voltage, has high sensitivity and low-noise characteristics and can attain high-speed response under low voltage.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a sectional view of an avalanche photodiode in an embodiment 1 according to the present invention.
FIG. 2 is a sectional view of an avalanche photodiode in a comparative example.
FIG. 3 is a graph showing a field distribution in the section of the avalanche photodiode of embodiment 1.
FIG. 4 is a graph showing a field distribution in the section of an avalanche photodiode in a comparative example.
FIG. 5 is a graph showing the relation between the multiplication factor of a multiplication layer 6 and the multiplication factor of a light-absorbing layer 4 in the avalanche photodiode of embodiment 1 in contrast to that of a comparative example.
FIG. 6 is a graph showing the relation between the multiplication factor of the multiplication layer 6 and the ratio of ionization rates in an avalanche photodiode in an embodiment 1 in contrast to that of a comparative example.
FIG. 7 is a graph showing carrier running time in relation to the thickness of a multiplication suppressing layer in the avalanche photodiode of embodiment 1.
FIG. 8 is a graph showing the frequency characteristics of the avalanche photodiode of embodiment 1 in contrast to that of a comparative example.
FIG. 9 is a sectional view of an avalanche photodiode in an embodiment 2 according to the present invention.
FIG. 10 is a sectional view of an avalanche photodiode in an embodiment 3 according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Embodiment 1
First, a specific structure of an avalanche photodiode in an embodiment 1 will be clarified by way of brief explanations of a process of producing the avalanche photodiode of the embodiment 1 according to the present invention.
The avalanche photodiode of the embodiment 1 is a plane light-receiving type separated absorption and multiplication avalanche photodiode (SAM-APD (Separated absorption and Multiplication-Avalanche Photo Diode)).
First, a p-type InP buffer layer 2 (Be: 5×10 18 cm −3 ), a p-type InGaAs multiplication suppressing layer 3 (Be: 5×10 17 cm −3 ), an i-type InGaAs light-absorbing layer 4 , a p-type InP field limiting layer 5 (Be: 4.5×10 17 cm −3 ), an i-type AlInAs multiplication layer 6 , an i-type InP etching stopper layer (not shown), an n-type AlInAs cap layer 7 (Si: 5×10 18 cm −3 ) and an n-type InGaAs contact layer 8 (Si: 5×10 18 cm −3 ) are formed one by one by epitaxial growth. As a crystal growth method, a solid source or gas source MBE method, metalorganic chemical vapor deposition (MOCVD) method or the like is preferable.
It is to be noted that in the above examples, less diffusible Be is added as the impurities to be added to the multiplication suppressing layer. However, in the present invention, C, Mg, Si, S and the like which are likewise less diffusible may be added besides Be.
Next, the n-type InGaAs contact layer 8 and n-type AlInAs cap layer 7 around the part to be the light-receiving region are removed by selective etching using an aqueous mixed solution comprising an organic acid such as citric acid, aqueous hydrogen peroxide and water until the surface of the i-type InP etching topper layer is exposed. As a result, a cyclic groove surrounding the light-receiving region is formed. In this case, as the etching mask, a resist which is patterned by known lithographic technologies is used.
In succession, the cyclic groove region is ion-implanted with titanium (Ti) or the like to offset the effect of the p-type to a depth extending to the vicinity of the p-type InP limiting layer, followed by heat-treating at a temperature of 600° C. or more to activate the ions, thereby effectively reducing the carrier density in the p-type InP field limiting layer around the light-receiving region. This region 9 doped with Ti ions functions as a guard ring. With regard to the type of ion to be implanted, the same effect is also obtained by using elements such as H, He, Ne, C, O, Ar, B, Fe and Cr besides Ti.
Next, Zn is used as the source of impurities to diffuse Zn selectively to an outside region on the outside of the cyclic groove by a thermal diffusion method to transform the n-type AlInAs layer and the n-type InGsAs contact layer to a p-type AlInAs layer and a p-type InGaAs contact layer 11 respectively. Next, a part of each of the n-type InGaAs contact layer 8 and p-type InGaAs contact layer 11 is removed by selective etching to make these layer have desired shapes. Then, an antireflection film/passivation film 12 made of, for example, SiN x is formed on the surface of the wafer.
In the regions where the surface passivation film is selectively removed on each upper part of the n-type InGaAs contact layer 8 and the p-type InGaAs contact layer 11 formed into desired shapes, a first electrode 21 is formed on the n-type InGaAs contact layer 8 which is the light-receiving region and a second electrode 22 is formed at such a position as to surround the cyclic groove on the p-type InGaAs contact layer 11 on the outside of the light-receiving region by using an alloy such as AuZn, AuTi, AuTiPt or AuGeNi.
For connection with outside circuits, a first electrode bonding pad 21 a and a second electrode bonding pad 22 a that bond gold wires to the first electrode 21 and second electrode 22 respectively are formed, and a first electrode lead wire and a second electrode lead wire are formed between the first electrode 21 and the first electrode bonding pad 21 a and between the second electrode 22 and the second electrode bonding pad 22 a to electrically connect the both respectively. The major part of the APD as shown in FIG. 1 is completed through the processes as mentioned above.
The avalanche photodiode constituted in the above manner in the embodiment 1 is characterized by the formation of the p-type InGaAs multiplication suppressing layer 3 between the p-type InP buffer layer 2 and the i-type InGaAs light-absorbing layer, whereby the ratio of ionization rates can be improved and the running time of carriers can be shortened.
The characteristics of the avalanche photodiode of the embodiment 1 will be explained hereinbelow by way of appropriately comparing the avalanche photodiode of the embodiment 1 provided with the p-type InGaAs multiplication suppressing layer 3 with an avalanche photodiode ( FIG. 2 ) of a comparative example provided with no p-type InGaAs multiplication suppressing layer 3 .
First, each specific structure of the avalanche photodiodes of the embodiment 1 and the comparative example was assumed to evaluate field distribution and field strength in the vicinity of the multiplication layer 6 .
The performance of the avalanche photodiode of the embodiment 1 was simulated based on the film thicknesses and carrier densities shown in Table 1 and the performance of the avalanche photodiode of the comparative example was simulated based on the film thicknesses and carrier densities shown in Table 2.
TABLE 1
Film thickness
Carrier density
(nm)
(cm −3 )
i-type AlInAs
200
5 × 10 14
multiplication layer 6
p-type InP field
50
4.5 × 10 17
limiting layer 5
i-type InGaAs light-
1000
—
absorbing layer 4
p-type InGaAs
300
5 × 10 17
multiplication
suppressing layer 3
TABLE 2
Film thickness
Carrier density
(nm)
(cm −3 )
i-type AlInAs
200
5 × 10 14
multiplication
layer 6
p-type InP field
50
4.5 × 10 17
limiting layer 5
i-type InGaAs
1300
—
light-absorbing
layer 4
The results of the simulation are shown in FIG. 3 (embodiment 1) and in FIG. 4 (comparative example).
The results of this simulation are based on calculation made using a field assumed to cause a multiplication of about 10 in the AlInAs multiplication layer 6 .
In the embodiment 1 as shown in Table 1 and FIG. 3 , the insertion of the InGaAs multiplication suppressing layer 3 makes thinner the i-type InGaAs light-absorbing layer 4 , to which a high field is applied, than a conventional light-absorbing layer while the i-type InGaAs light-absorbing layer 4 and the p-type InGaAs multiplication suppressing layer are made to have a total thickness above a fixed level.
Specifically, in the avalanche photodiode of the embodiment 1, the i-type InGaAs light-absorbing layer 4 to be depleted is formed in a thickness more than a fixed level on the field limiting layer 5 side and the p-type InGaAs multiplication suppressing layer 3 which is a non-depletion semiconductor light-absorbing layer to be undepleted is formed on the opposite side, thereby forming the light-absorbing layer from the i-type InGaAs light-absorbing layer 4 to be depleted and the p-type InGaAs multiplication suppressing layer 3 to be undepleted.
This makes it possible to make thin the InGaAs light-absorbing layer 4 to which a field is applied while the thickness of the whole light-absorbing layer is maintained at more than a fixed level, and it is therefore possible to suppress multiplication in the InGaAs light-absorbing layer 4 .
In the avalanche photodiode constituted in the above manner in the embodiment 1, the total thickness of the i-type InGaAs light-absorbing layer 4 and the p-type InGaAs multiplication suppressing layer is designed to be preferably in a range from 0.7 μm to 2.0 μm and more preferably in a range from 1 μm to 1.5 μm to prevent a deterioration in light absorbance.
Also, the concentration of impurities in the p-type InGaAs multiplication suppressing layer 3 is designed to be preferably 5×10 16 cm −3 or more and more preferably 5×10 17 cm −3 or more to prevent the layer 3 from being depleted.
Next, in the structures of the embodiment 1 and comparative example, the relation between the multiplication factor in the i-type AlInAs multiplication layer 6 and the multiplication factor in the i-type InGaAs light-absorbing layer 4 is shown in FIG. 5 . It is found that as shown in FIG. 5 , the multiplication factor of the i-type InGaAs light-absorbing layer 4 is suppressed even in the range where the multiplication factor in the AlInAs multiplication layer 6 is high in the avalanche photodiode of the embodiment 1 into which the InGaAs multiplication layer 3 is inserted. It is also found that as shown in FIG. 6 , the ratio of ionization rates is improved by inserting the InGaAs multiplication suppressing layer 3 on viewing from the relation between the multiplication factor and the ratio of ionization rates.
Next, FIG. 7 shows the results of calculation as to the relation between the thickness of the InGaAs multiplication suppressing layer 3 and the running time of carriers. It is found from this FIG. 7 that in the case where the total thickness of the InGaAs absorbing layer 4 and InGaAs multiplication suppressing layer 3 is set to 1.3 μm, the thickness of the InGaAs multiplication suppressing layer 3 is designed to be preferably 0.6 μm or less and more preferably 0.45 μm or less to thereby shorten the running time of carriers. In other words, the band defined by the running time of carriers is improved. Specifically, the carriers generated in the multiplication suppressing layer 3 are diffused, reach the depleted layer and then drawn as signals. However, when the thickness of the multiplication suppressing layer is 0.60 μm or less, the time required to draw electrons as signals is made shorter than in the case of using only drift, which more improves high-speed response characteristics, frequency characteristics and GB product.
In this case, the lower limit of the InGaAs multiplication suppressing layer 3 is designed taking the multiplication suppressing effect into account, and for example, designed to be 0.1 μm or more.
It is found from the above result that the insertion of the InGaAs multiplication suppressing layer 3 prepared by adding impurities to the InGaAs light-absorbing layer makes it possible to improve the ratio of ionization rates and to shorten the running time of carriers. It is found that this can make improvements in band-broadening of elements and GB product (gain-bandwidth product) and also in high-speed response characteristics.
Next, the avalanche photodiode of the embodiment 1 and the avalanche photodiode of the comparative example were produced experimentally and evaluated. The results are shown below.
It is to be noted that in the avalanche photodiode of the embodiment 1, the total thickness of the InGaAs absorbing layer 4 and InGaAs multiplication suppressing layer 3 was set to 1.3 μm and in the avalanche photodiode of the comparative example in which no InGaAs multiplication suppressing layer is inserted, the thickness of i-type InGaAs absorbing layer was set to 1.3 μm to make equal the total thickness of the InGaAs absorbing layer.
The frequency characteristics of the experimentally produced avalanche photodiode of the embodiment 1 and avalanche photodiode of the comparative example are shown in FIG. 8 . As is clear from FIG. 8 , the insertion of the InGaAs multiplication suppressing layer 3 ensures that higher cut-off frequencies are obtained and a high GB product is also obtained in almost all region.
Generally, because a depleted region is narrowed when the InGaAs multiplication suppressing layer 3 is inserted, resulting in an increase in electrostatic capacity of elements, leading to a deterioration in the cut-off frequency determined by elemental capacitance and elemental resistance among the factors determining the cut-off frequency. The above improvement in high-speed response characteristics in the avalanche photodiode of the embodiment 1 irrespective of this fact is considered to be due to the shortening of the running time of carriers and to the improvement in the ratio of ionization rates.
As to also the sensitivity characteristics of the avalanche photodiode of the embodiment 1, any deterioration in sensitivity which was caused by the formation of the region to which impurities were added was not observed and therefore an efficiency as high as 0.85 A/W was obtained. This showed that carriers were not recombined in the InGaAs multiplication suppressing layer 3 and almost all the generated carriers were drawn as signals.
In the avalanche photodiode of the embodiment 1 as mentioned above, impurities in the InGaAs multiplication suppressing layer 3 preferably have such a concentration gradient such that the concentration of impurities on the InGaAs absorbing layer 4 side is lower.
If the InGaAs multiplication suppressing layer 3 is constituted of a p-type graded InGaAs layer having impurity concentration gradient, electrons generated in the multiplication suppressing layer 3 are accelerated by an internal electric field and can move at a very high velocity. Therefore, the time required to draw these electrons as signals is shortened, leading to an improvement in high-speed response characteristics and to a more improvement in frequency characteristics.
It is more preferable that the impurity concentration gradient of the multiplication suppressing layer 3 be controlled such that the internal electric field is close to 4000 V/cm.
Also, though the multiplication layer 6 may be constituted of various semiconductors, it is constituted of, preferably, a semiconductor layer containing Al or more preferably a semiconductor layer containing Si, whereby the ratio of ionization rates can be increased. Also, a multiplication layer having a super lattice structure may be constituted using a semiconductor containing Al. A large ratio of ionization rates may also be obtained using a multiplication layer having a super lattice structure.
Embodiment 2
FIG. 9 is a sectional view showing the elemental structure of an avalanche photodiode having a multiplication layer comprising i-type InP.
A process of producing the avalanche photodiode of the embodiment 2 will be briefly explained to clarify the structure of the avalanche photodiode of the embodiment 2.
In this method, first an n-type InGaAs multiplication suppressing layer 103 (Si: 1×10 18 cm −3 ), an i-type InGaAs light-absorbing layer 104 , an i-type InGaAsP layer 105 , an i-type InP multiplication layer 106 and an i-type InGaAs contact layer 107 are respectively formed one by one on an n-type InP substrate 101 by epitaxial growth (impurities to be added to the crystal and the concentration of the impurities are shown in the above parenthesis). As the crystal growth method, solid source or gas source MBE, metalorganic chemical vapor deposition (MOCVD) method or the like is preferably used.
Next, the cyclic groove region is implanted with Be ions, followed by heat treating to activate these ions, thereby forming a low-concentration p-type region 109 in the vicinity of the light-receiving region, allowing this region to function as a guard ring. The same effect is obtained by using an element such as Mg or C other than the aforementioned Be as the type of ion to be implanted.
Next, Zn is used as an impurity source and diffused selectively to the light receiving section by a thermal diffusion method to transform the i-type InP layer 106 and the i-type InGaAs contact layer 107 into a p-type InP layer 106 a and a p-type InGaAs contact layer 111 . Here, the diffused depth of Zn is controlled so that the i-type InP layer is left between the p-type InP layer 106 a and the i-type InGaAsP layer 105 . This i-type InP layer in which Zn is not diffused functions as the multiplication layer 106 .
Next, parts of the p-type InGaAs contact layer 111 are removed by selective etching to make the layer into a desired shape. Then, an antireflection film/passivation film 112 made of, for example, SiN x is formed on the surface of the wafer.
In succession, in the region where the surface passivation film 112 is selectively removed on a upper part of the p-type InGaAs contact layer 111 formed into a desired shape, an electrode 22 is formed on the p-type InGaAs contact layer 111 which is the light-receiving region by using an alloy such as AuZn, AuTi or AuTiPt.
The avalanche photodiode of the embodiment 2 as shown in FIG. 9 is completed through the steps as mentioned above.
In the avalanche photodiode of the embodiment 2 which is constituted in the above manner, Si as impurities to be minority carriers (holes in this case) that are multiplied in the InP multiplication layer is added to the i-type InGaAs absorbing layer 104 in the same manner as in the case of the embodiment 1. As shown in FIG. 9 , the carriers multiplied in the i-type InGaAs absorbing layer 104 are decreased by inserting the n-type InGaAs multiplication suppressing layer 103 also in this embodiment 2. The ratio of ionization rates are thereby expected to be improved and also the effect of reducing the running time of carriers can be expected. These effects ensure improvements in noise characteristics and high-speed response characteristics.
The preferable ranges of each film thickness and total film thickness of the n-type InGaAs multiplication suppressing layer 103 and the i-type InGaAs absorbing layer 104 in the embodiment 2 are the same as those in the embodiment 1.
Also in the avalanche photodiode of the embodiment 2, the n-type InGaAs multiplication suppressing layer 103 preferably has such an impurity concentration gradient that the impurity concentration on the InGaAs absorbing layer 104 side is lower. Electrons generated in the multiplication suppressing layer 103 are thereby accelerated by an internal electric field and can move at a very high velocity.
Embodiment 3
In the embodiments 1 and 2, the structure in which light is incident from the upper surface of the element is described by way of explaining the process of producing the element. A semiconductor light-receiving element generically called a waveguide type avalanche photodiode in which light is incident from the element side (cleavage plane side) as shown in FIG. 10 can be expected to be improved in the ratio of ionization rates by inserting the InGaAs multiplication suppressing layer 203 .
The avalanche photodiode of the embodiment 3 is produced in the following manner.
First, a p-type InGaAs conductive layer 201 , a p-type InP layer 202 , a p-type InGaAsP light-confining layer 211 , a p-type InGaAs multiplication suppressing layer 203 , an i-type InGaAs light-absorbing layer 204 , a p-type InGaAsP field limiting layer 205 , an i-type AlInAs multiplication layer 206 , an n-type InP layer 207 and an n-type InGaAs contact layer 208 are respectively formed by epitaxial growth on a semi-insulation InP substrate 1 to which Fe is added as impurities. As the crystal growth method, solid source or gas source MBE, metalorganic chemical vapor deposition (MOCVD) method or the like is preferably used.
After each layer is grown, a laminate part constituting the light-receiving section is left and the outside of the laminate part is etched until the p-type InGaAs conductive layer 201 is exposed.
Then, an anode electrode is formed on the exposed p-type InGaAs conductive layer 201 , a cathode electrode 221 is formed on the n-type InGaAs contact layer 208 and the laminate part is entirely coated with a passivation film 212 made of, for example, SiN x .
Like the avalanche photodiodes obtained in the embodiments 1 and 2, the avalanche photodiode ( FIG. 10 ) of the embodiment 3 constituted in the above manner can be improved in the ratio of ionization rates since it is provided with the InGaAs multiplication suppressing layer 203 and also, the running time of carriers is shortened, which makes it possible to improve noise characteristics and high-speed response characteristics.
The preferable ranges of each film thickness and total film thickness of the multiplication suppressing layer 203 and the light-absorbing layer 204 in the embodiment 3 are the same as those in the embodiment 1.
Also in the avalanche photodiode of the embodiment 3, the p-type InGaAs multiplication suppressing layer 203 preferably has such an impurity concentration gradient that the impurity concentration on the light-absorbing layer 204 side is lower. Electrons generated in the multiplication suppressing layer 203 are thereby accelerated by an internal electric field and can move at a very high velocity. | An avalanche photodiode has improved low-noise characteristics, high-speed response characteristics, and sensitivity. The avalanche photodiode includes a first conductivity type semiconductor layer, a second conductivity type semiconductor layer, a semiconductor multiplication layer interposed between the first conductivity type semiconductor layer and the second conductivity type semiconductor layer, and a semiconductor light-absorbing layer interposed between the semiconductor multiplication layer and the second conductivity type semiconductor layer. The avalanche photodiode further comprises a multiplication suppressing layer which suppresses multiplication of charge carriers in the semiconductor light-absorbing layer, has a thickness of 0.6 μm or less, and is located between the semiconductor light-absorbing layer and the second conductivity type semiconductor layer. The thickness of the semiconductor light-absorbing layer is 0.5 μm or more. | 7 |
CROSS REFERENCE TO RELATED APPLICATIONS
This Application is a Continuation-In-Part of application Ser. No. 10/016,722 now ABANDONED having a filing date of Oct. 30, 2001 which in turn is a Continuation-In-Part of application Ser. No. 9/800,752 having a filing date of Mar. 7, 2001 now ABANDONED.
STATEMENT REGARDING FED SPONSORED R & D
(none)
FIELD OF THE INVENTION
This invention relates to an interactively modulable support apparatus, such as a mattress, having a layer of pressure adjustable self-inflating, open-cell, flexible polyurethane foam core and a layer of mattress spring coils. Both layers are independently adjustable as to softness/hardness, but also interactively modulable in the way that adjustment of the foam core layer modifies the characteristics of the coil spring layer.
BACKGROUND OF THE INVENTION
This invention is a multiple layer combination mattress. One or more layers are self-inflating elastomeric open-cell polyurethane foam and another layer is a section having mechanical coil springs therein. Both layers are individually, as well as interactively adjustable as to their hardness and softness (indentation force deflection—IFD) and support (density).
Various designs have been made in the past to control the hardness, softness, and support firmness of foam layers within a mattress by using different zones of foam layers for different parts of the body, or by controlling the firmness or responsiveness of coil springs in mattresses, but to control both layers so that they can be adjusted by the user, foam and coil independently and interactively in one mattress, has not been achieved and is not found in the prior art in the manner of this invention.
U.S. Pat. No. 2,779,034 to Arpin discloses a firmness adjustment for mattresses involving a standard coil spring mattress wherein standard coil springs are enclosed by a loosely fitting airtight cover. A vacuum pump can be applied to the cover in order to compress the coil springs within the mattress to make them harder. Although the disclosure of Arpin mentions ‘rubber foam’ or similar material, it does not involve any open-cell, self-inflating foam varieties, nor does Arpin teach that the respective density and IFD values, which are determined by the cellular structure of the foam or foam-like material he may have had in mind, may be modulated to result in a softer or harder mattress without sacrificing support-firmness in the process of multiple comfort adjustments. The present invention, however, modulates the foam core layers' characteristics in a way as to bring pressure resulting from that modulation to bear onto the coil spring layer, thus interactively and incrementally increasing this layer's firmness in a predetermined range of modulation, whereas Arpin only applies a vacuum to the coil spring section to increase indentation force deflection (increasing firmness) of the coil spring layer.
A further fundamental difference lies in the fact that the present teaching does the opposite and still at the same time increases support. This effect is achieved by utilization of the properties of special foam material which is manufactured and applied expressly for the purpose of modulating indentation force deflection and density from maximum firm state to a chosen state of softness without weakening the desirable effect of high support.
U.S. Pat. No. 3,611,524 illustrates a method of assembling a mattress. The disclosure involves a ready-made mattress either of the coil spring type or foam type which is initially wrapped in an airtight sheet of plastic and a vacuum pump is applied to the wrapped combination and the coil spring mattress or the foam mattress will collapse under the force of the vacuum and either of the collapsed forms can now be inserted into a finishing cover. Once the vacuum in either mattress is released, either one of the mattresses will expand to snugly fit within the outer covering. This disclosed invention is designed for a one time use only. Moreover, there is a teaching within this reference that the preliminary wrapping sheet should be removed. In contrast to this, the invention at hand can be used time and time again to adjust the various levels of firmness desired. No disclosure within U.S. Pat. No. 3,611,524 is made that the aim is to adjust comfort levels. A manufacturing process is described wherein a filling material is reduced in volume by removing air from it to be able to quickly and efficiently introduce it in a sleeve before it has time to expand again. This method is now used worldwide by upholsterers and furniture manufacturers.
U.S. Pat. No. 3,872,525 to Lea discloses a camping mat using a self-inflating foam within an airtight outer cover that is vulcanized to the inner foam layer. The air within can be removed by compressing the structure whereby the foam layer collapses, allowing the mat to be rolled up into a compact package. The firmness (IFD) or density can not be modulated freely because of the thinness and light weight of the foam layer used in camping mats. Furthermore, compressing the camping mat by hand does not expel the air uniformly from all the foam cells but only in the area being compressed by hand. Clearly, modulating comfort and firmness were not in the mind of the inventors, but a method of decreasing the mat's volume for easy packing and transport
The invention at hand uses a thicker, higher density foam core to start with, which can be adjusted infinitely to multiple levels of firmness and support not found in the prior art and thus adjusts the coil spring layer accordingly. Its priority lies with comfort modulation and should not be considered a method of packaging a camping mat into a small size to be carried in a backpack.
U.S. Pat. No. 4,025,974 discloses a self-inflating air mattress/mat including an airtight flexible envelope which encloses a core of resilient, open cell, lightweight foam material, substantially the entire upper and lower portions of which are bonded to the envelope. Heated platens are applied to this lay-up, followed by creating a vacuum in the interior, cooling and pressurizing the assembly, then moderately pressurizing the whole. The invention at hand does not bond any outer coverings to the enclosed foam layer. On the contrary, this invention uses a device to distance the foam from the cover in order to enhance airflow and to prevent the foam or cover from obstructing the valve when air is drawn out of the mattress or when it is self-inflating.
Again, the aim of the teaching in this patent is to compress the mat for easy transport in a backpack. Furthermore, there is no indication of a further objective to intentionally modulate the foam density or IFD within the foam core with the aid of a vacuum to obtain multiple levels of firmness and support. Lastly, Lea proposes to utilize foam types with a density not greater than 1.2 or 1.5 in their original state. No mention is made of interactivity with other mattress layers.
U.S. Pat. No. 4,711,067 teaches the packaging of a mattress wherein the thickness of an elastic structure of a mattress is reduced. An extra cover is fitted over the mattress which is fitted over the structure of a pressing device. This procedure will completely flatten the mattress for roll-up. There is no disclosure to control any comfort level or to apply a vacuum pump to do so, nor of any interactivity with other mattress layers.
U.S. Pat. No. 4,944,060 illustrates a mattress having a plurality of discrete, air permeable cells which are to some extent hydrophobic. In opposition to the invention at hand there is no block of a foam core of any kind, no covering encasing or envelope and there is no teaching of complete air evacuation, nor mention of interactivity with other mattress layers.
The invention at hand does not use any pressurized air but a vacuum only, whereas the above art teaches the opposite, namely pressurization of a chamber to increase the hardness of the support surface. If air were allowed to escape from the chamber, the support surface would collapse and cause a hammock effect.
In the invention at hand interactive foam core never exhibits a collapsing hammock effect when air is removed from within the foam cells, but adjusts to the body's pressure points locally as density within the foam core increases to offer more support, and exerts less pressure on the adjacent coil spring layer to also increase softness and comfort.
U.S. Pat. No. 5,947,168 illustrates a method and apparatus for rapidly deflating and substantially emptying an inflatable air chamber, the chamber being a mattress. This disclosure does not involve any self-inflating alternating density polyurethane foam and therefore, is not pertinent to the invention at hand.
U.S. Pat. No. 6,098,378 discloses a method of packaging a single mattress to a small size to be conveniently carried. In this method and apparatus, the foam mattress is compressed to fit into a hard container for shipment. At the point of sale, the mattress is extracted and expands to its original shape. This appears as a one time use only and there is no teaching of adjusting the comfort level of a user through modulation of pressure.
Furthermore, none of the above prior art teachings take advantage of the expanding force of a self-inflating foam core that while it is in the process of expanding, compresses an adjacent core and modifies the properties of that core.
SUMMARY OF THE INVENTION
The invention results from the realization that a combination of a self-inflating, adjustable density, variable IFD, open-cell flexible polyurethane foam core with a mattress layer having coils therein greatly enhances the versatility of this mattress combination, offering great variety in adjustable levels of comfort.
The invention teaches how the Indentation Force Deflection (IFD) and density properties of a certain quality range of flexible open-cell polyurethane foam can be modulated by removing some of the air from within the foam cells and altering the cellular structure of the foam core. High density foam is more expensive (such as visco-elastic foam). They provide great comfort. The focal teaching of this invention is how to modulate a comparatively inexpensive, lower density foam to feel similar to a high density foam, and attain support and comfort characteristics of a higher density, more expensive foam, through layer interactivity between foam and traditional coil spring arrangements, without locking the user into one fixed comfort level, but give him a wide choice between very hard and very soft comfort.
IFD and density modulation are achieved by manipulating flexible polyurethane foam or material of similar characteristics. This art teaches that this material is fashioned in a particular form and that it has to be of a molecular composition as to permit the extraction of air in the alveolate structure in a uniform manner, thus increasing material density equally uniformly. A further specialty of this material is that, by virtue of its structure, particular manufacturing and finishing processes, it affords in its low IFD number modulated state commensurably higher firmness stability, heretofore only associated with foam or similar material of a very much higher density number. Finally, it is much lighter in weight than the latter and can be reduced in size and volume for easy transport and storage.
This teaching also involves different reversible mattress combinations that one or more users may adjust differentially and individually to his or her liking, depending which side of the bed they choose to recline upon (left or right side of the bed, or the reverse surface). It also demonstrates that many incremental levels of firmness or softness may be achieved by one piece of foam as it changes from low density and high IFD to a high density low IFD more desirable foam, as well as when it interacts with other adjacent coil cores, changing their particular IFD and firmness characteristics.
In the present invention a custom fan-style vacuum pump that draws air out of the foam core to double its density and to reduce its IFD value considerably. After only a few seconds of the pump's operation the foam feels like a high density, resilient foam with an IFD of under 20, supported by an equally modulated coil spring layer with adjusted softness. Since the vacuum pump comes equipped with variable speed and remote control memory settings this transformation occurs at the speed and in increments desired by the user.
The experiments conducted entailed a user reclining on the foam/coil spring original firm configuration and subsequently adjusting the density and IFD settings within the foam core. It was observed that the user's heaviest parts of the body sank into the foam and were contoured progressively as the density increased and the IFD decreased. Thanks to this functionality, as well as the underlying coil spring layer, no collapsing or hammock effect took place within the mattress, which was lighter and thinner than any other mattresses using a different technology—reduction in weight, bulk and cost being industry priority requirements for new mattress technology.
This invention takes advantage of the adjustability of the self-inflating foam core as to comfort and also uses said adjustability to change the properties of the coil mattress above or below the foam mattress core. The structure of this combination allows the mattress cores to be used in two horizontal juxtaposed orientations. Either the foam part of the mattress faces upwards or the coil part of the mattress faces upwards. This is decided by the user of the mattress. In particular, air can be exhausted from the foam part of the mattress combination uniformly with the aid of a vacuum pump, which results in increasing the density of the foam core and decreasing the IFD within the core for a softer feeling foam core with more support. Since the coil core and the foam core are trapped within an airtight outer chamber the properties of said coil core will change as the foam core expands or contracts. Moreover, and like Arpin's teaching, the coil core combination of the mattress combination may additionally be compressed by evacuating the air of the chamber containing the coils which would result in increasing the hardness of that part of the mattress but would also affect the adjacent foam core. This interactivity in adjustability contributes greatly to the versatility of such a mattress combination.
The basic configuration of this invention, which comes in a broad variety of combinations between foam and spring coil cores and compartments, takes the form of a mattress, as one example of among a large number of support apparatuses, with at least three chambers each containing a valve communicably extending to the outside air. The valves contribute greatly to the versatility of the invention as will be explained further.
The first hermetically sealed chamber is an overall outer enclosure of the total mattress combination and will trap and compress the other two chambers if evacuated of air. A second chamber contains an assembly of coil springs, while a third chamber contains a core of self-inflating polyurethane foam. As mentioned above, the first layer encompasses the second and third layers tightly. If the chamber of self-inflating foam is allowed to inflate, it compresses the coil chamber trapped above or below it. By compressing the coils either directly by evacuating air with a vacuum from the coil chamber, or by compressing the coil chamber with the rising force of the self-inflating foam chamber, the coil portion of the mattress becomes firmer. On the other hand, if some air was evacuated from the foam chamber the coil portion would relax and feel softer.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 0 shows a traditional mattress with different foam zones and coil spring core;
FIGS. 1A and 1B shows air foam, and coil foam mattresses with weights placed upon their surface;
FIG. 2 shows one airtight chamber, two cores and a single valve;
FIG. 3 shows one airtight chamber, three cores with a single valve;
FIG. 4 shows two airtight chambers, two cores and two valves;
FIG. 5 shows three airtight chambers, three cores and three valves;
FIG. 6 shows three airtight chambers, two cores and three valves;
FIG. 7 shows subdivided chambers with a valve each;
FIG. 8 shows a 4-chamber mattress in a cut-away view;
FIG. 9 shows a coil foam mattress in the present invention with weights placed on the surface;
FIG. 10 shows a coil foam mattress in the present invention when weights are removed from the surface with the valve closed;
FIGS. 11 a and 11 b shows the same combination mattress in different states of self-inflation with one or more valves and one or more air permeable distancing elements;
DETAILED DESCRIPTION OF THE INVENTION
FIG. 0 shows a traditional mattress with a coil spring core and many diverse foam zones ( 01 ). The foam layers ( 01 ) typically have different density and IFD ratings to accommodate the weight of various parts of the body, such as the head, shoulders, middle body, and feet. The coil core ( 02 ) supports the above layers of foam and is surrounded by a quilted fabric or ticking ( 03 ) which is traditionally not airtight and serves as outer decoration as well as holds the parts of the mattress together as one whole mattress. Additionally (not shown), the whole mattress is typically surrounded by a quilted cover, for added comfort and aesthetics.
The disadvantages of said mattress is that it is often very expensive, and yet offers one fixed comfort level that can not be selectively modulated by the user. Yet other mattress inventions have interchangeable foam compartments to achieve different comfort levels, however said multi-foam compartment mattresses become cumbersome due to a multitude of foam compartments that must be stored when not in use.
FIG. 1A shows a typical prior art foam-layer-plus-air-chamber mattress in which air bladders ( 1 ) can be pressurized by an air pump ( 2 ). The weights (W) represent a person reclining on top of the foam layer ( 3 ). The weights impress their mass on the mattress in the way a reclining person would, accumulating towards the area of least lateral support, that is, in the center. This results in a hammock effect, which is uncomfortable for a person resting on the mattress. Moreover, when air is let out of the bladder(s), the entire apparatus collapses and does no longer support the reclining body, the hammock effect being present all the way down through partial deflation. In this arrangement the air chamber is modulated below the foam layer without any interactive effect on the foam. In case of loss of pressure, the air chamber wobbles and sways, rendering the structure unstable and even more uncomfortable.
FIG. 1B shows the same configuration as FIG. 1A, but in a combination of a traditional mattress chamber ( 6 ) with coil springs ( 7 ), and a layer of foam ( 3 ) on top for additional comfort. The weights (W) represent a person reclining on the mattress and create the hammock effect in the middle, because their force is greater than both underlying layers of air and coil springs can support without deformation. Deform they must, otherwise they would have to be rock hard and uncomfortable, defeating the basic purpose of a mattress. Both types of base layers will spring back immediately as soon as the weights are removed or only partially displaced, exerting a high upward pressure. This characteristic is undesirable in a mattress, too, because each movement of weight, such as found in a typical person's sleeping pattern, shifts the hammock effect around on the mattress.
In contrast to the above, this invention modulates the density and the spring-back-force (IFD) of self-inflating, open-cell, flexible polyurethane foam in combination with traditional coil spring chambers, thus doing away with these problems. Any weight distribution on top of such a foam & coil spring mattress, such as from the head, abdomen or the legs, affects the deflection of the foam layer surface only locally, and upward recovery (spring-back) is a slow process of re-directed airflow through the cell structure of the foam layer. The underlying coil spring layer is not subjected to concentrated pressure from the weights above it. Consequently, no hammock effect will be evidenced.
Depending on the volume of air in the foam layer, there can even be a state where no recovery takes place; where no upward pressure is exerted, and still a high level of comfort is sustained. This is based on the underlying principle inherent in the invention that, when air is removed progressively from a hermetically sealed foam core, the foam's density increases. At the same instance, its Indentation Force Deflection (IFD or spring-back force) is progressively decreased, making the foam core softer. This process of modulation spans from full inflation to practically zero. In the extreme case, when too much air is removed, the foam hardens, defeating the purpose of a mattress, e.g. to provide comfort.
The aim of the description of this invention is threefold: to show that modulation of air volume within the foam cells defeats the undesirable hammock effect, that it provides a sleeper with new, up to now unknown variety in choosing his level of comfort, and how traditional coil spring mattress chambers can be adjusted interactively for additional comfort, all this being achieved at the same time.
FIG. 2 shows one airtight chamber with two cores inside. Chamber (A) is the main chamber constituting the overall mattress. The lower section (B) is a self-inflating foam core (SF 1 ), above which is placed a coil spring section (C) with a number of coil springs ( 21 ), normally placed in individual fabric sleeves (not shown). Above and below the coil spring section protective layers ( 23 ) are provided to prevent the ends of the coil springs from protruding into a person lying on top of the chamber (A) and into the foam core (B) below.
A valve, or a plurality of valves ( 22 ), installed in the wall ( 20 ) of the main chamber (A), serves to exhaust air from the mattress. When air is exhausted through the valve, the foam core (SF 1 ) will be compressed uniformly and the coil springs in the coil spring section will also be compressed. As a result, both density and IFD values of the two sections will change. The surface of the coil spring section will harden while, inversely, the surface of the foam core section will soften. This mattress may be used either with the foam or the coil spring section facing upwards.
FIG. 3 shows a combination mattress with one overall airtight chamber (A), in which are placed two self-inflating foam cores (SF 1 and SF 2 ) in the bottom ( 33 ) and the top ( 34 ) positions, while a coil spring core ( 31 ), having protective layers ( 35 ), is sandwiched in between. In the outer wall of chamber (A) a valve ( 32 ) has been provided through which air can be exhausted. When this occurs, the two foam cores ( 33 and 34 ) and the coil spring core springs ( 31 ) are compressed. Under compression, the surfaces of the foam cores will soften as a result of decreasing IFD, while the coil spring core, in contrast, will increase in hardness because the coil springs are tensioned and want to return to their initial relaxed state.
FIG. 4 shows a mattress combination with two chambers: an overall chamber (A) with wall ( 40 ), and a second chamber (B) inside. (B) is completely self-contained and envelopes a self-inflating foam core (SF 1 ). The upper part of chamber (A) contains a coil spring core ( 47 ) with a number of coil springs ( 48 ). Protective layers ( 43 ) are placed each above and below the coil springs. Two valves ( 42 and 44 ) are provided, whereby upper valve ( 42 ) serves to exhaust air from the overall chamber (A), resulting in the compression of the upper coil spring core which will harden. Lower valve ( 44 ) serves to exhaust air from chamber (B) exclusively and independently from chamber (A), if so selected. Valve ( 44 ) leads to the interior of chamber (B) by penetrating both wall ( 40 ) of the overall chamber and wall ( 46 ) of chamber (B). This valve has an air permeable distancing element ( 45 ) attached its interior end to prevent valve-clogging by foam or cover material.
This mattress combination can be used on both sides. If so desired, the coil spring core can be used to lay on because of a desire of reclining on a harder surface, or the foam core side can be used because of a softer surface. When air is evacuated from the foam core (SF 1 ) in chamber (B), both chambers will be rendered softer because of the falling IFD value in chamber (B), but also because the coil spring core ( 47 ) will relax further due to the shrinking volume in chamber (B).
FIG. 5 shows a mattress combination with three chambers. The first (A) has an overall and sealed cover ( 50 ). Inside (A) are two chambers (B and C), each having a self-inflating polyurethane core (SF 1 and SF 2 ). Sandwiched between these is a traditional coil spring core ( 51 ) protected by foam layers ( 53 ) at both ends of the springs. (A) has a valve ( 52 ) for the purpose of evacuating air from that chamber, which will result in compressing the coil spring core, increasing its firmness. The upper and lower foam surfaces, being enveloped in separate chambers, remain unaffected. Chambers (B and C) also have independent valves ( 54 and 56 ), passing through both chamber walls into the interior of their respective foam core chamber, and each valve has an air permeable distancing element ( 55 and 57 ) attached. Through them air can be evacuated either from both chambers (B and C) simultaneously or independently, producing a large variety of different hardness or softness combinations. The sandwiched coil spring layer will be interactively modulated, since compression of either or both chambers (B) and (C) will result in a further extension of the springs.
FIG. 6 shows a three chamber (A, B and C) combination mattress. (A) is the overall chamber enveloping the other two (B and C) and has sealed wall ( 60 ). The lower chamber (B) is filled with a self-inflating polyurethane foam core (SF 1 ), enveloped in its own hermetically sealed cover. Inside the upper chamber (C) is a traditional coil spring core ( 61 ) and it also is hermetically sealed by its own cover ( 68 ). The coil spring core ( 61 ) has a protective foam layer ( 63 ) placed each above and below the springs. The overall chamber (A) has a valve ( 66 ) placed therein and through its own wall ( 60 ), fitted with an air permeable distancing element ( 67 ) on the interior, which prevents the cover ( 68 ) of chamber (C) from being drawn into the valve when the air is being evacuated from this chamber. Chamber (C) also has its own valve ( 62 ) which passes through both walls ( 60 ) of chamber (A) and ( 68 ) of (C).
Chamber (B) also has its own valve ( 64 ) passing through wall ( 60 ) of chamber (A) and wall ( 69 ) of chamber (B). Valve ( 64 ) is equally fitted with an air permeable distancing element to prevent the foam and covering from being drawn into the valve when air is evacuated from the foam core (SF 1 ), and it serves, in the opposite case, to distances the foam and cover from the valve when the foam core is allowed to self-inflate. The versatility of this mattress combination resides in the fact that all three valves can be operated selectively to increase or decrease the respective softness and hardness of the various cores or to decompress the whole mattress for storage or transport.
When the air is evacuated from chamber (C), the coil springs ( 61 ) will be compressed, offering a higher degree of firmness. On the other hand, when the air is being evacuated from chamber (B), the self-inflating foam core (SF 1 ) will soften but also allow chamber (C) to expand, offering a different level of softness/firmness combinations interactively. When air is being evacuated from (A), both chambers (B) and (C) will be compressed by the outer cover ( 60 ) and expel air, provided the respective chamber valves are open, resulting in the coil springs being harder to compress while the foam core will soften. The mattress can be used on either side if so desired.
FIG. 7 shows a mattress combination with 5 chambers which are hermetically sealed from each other. Overall chamber (A) with side wall ( 70 ) encloses four other chambers (B, C 1 , C 2 and C 3 ). Chamber (B) envelopes a traditional coil spring core ( 71 ) within its own sealed wall. Below it are placed three smaller self-inflating foam (SF) sections (C 1 , C 2 and C 3 ), each enclosed in their own outer wall envelopes. Arrow ( 75 ) indicates how the various cores and sections are associated with each other. The overall cover of chamber (A) has its own valve ( 72 ), combined with an air permeable distancing element ( 72 a ). Chamber (B) has its own valve ( 73 ) which passes through wall ( 70 ) of the outer chamber and through its own wall. The three smaller sections (C 1 , C 2 and C 3 ) below are filled with self-inflating foam and have their own valves ( 74 a , 74 b and 74 c ) and air permeable distancing elements (one is shown at 74 d ). Each valve of (C 1 , C 2 and C 3 ) pass though wall ( 70 ) of chamber (A) and through their own wall so that air can be evacuated from each chamber in a selective manner. The selectively modulable foam core chambers control various areas of hardness and softness of the coil spring layer, corresponding to upper, middle and lower body, thus greatly enhancing the versatility of the mattress.
FIG. 8 shows a mattress combination in a cut-away view, consisting of four chambers. An outer chamber with wall ( 80 ) fully encloses and hermetically seals three inner chambers (A, B, and C). (B) is the lower chamber with its own wall ( 82 ), enclosing a self-inflating foam core (SF 1 ). So is upper chamber (C) with wall ( 81 ), enveloping self-inflating foam core (SF 2 ). The fourth chamber (A) with its own wall ( 89 ) envelops a traditional coil spring core, and it is sandwiched between chambers (B) and (C). The coil spring core has protective layers ( 84 ) placed one above and one below the spring ends.
All four chambers are fitted with valves to selectively evacuate air. Valve ( 85 ) in cover ( 80 ) is fitted with an air permeable distancing element ( 85 a ) to avoid being blocked by wall ( 89 ) of chamber (A) when air is evacuated. ( 85 ) is by purpose placed in a position that, when air is evacuated from its chamber, the other three chambers are compressed, provided their respective valves are open. The lower chamber (B) with wall ( 82 ), has valve ( 88 ) with anti-blockage distancing element ( 88 a ) passing into its interior through the outer wall ( 80 ) of the overall cover and its own ( 82 ). The upper chamber (C) with sealed cover ( 81 ) completely envelopes the self-inflating foam core (SF 2 ). It has valve ( 86 ) with anti-clogging, air permeable, distancing element ( 86 a ), leading from its interior through its own wall ( 81 ) and through outer wall ( 80 ), so that only air from this chamber can be evacuated.
Chamber (A), which contains a traditional coil spring core, is sandwiched between (B) and (C). It has its own wall ( 89 ), completely enclosing the coil spring layer, so that air can only be withdrawn from it through valve ( 87 ). In order to so, this valve passes through its own wall ( 89 ) and outer wall ( 80 ). All four valves can selectively be activated to modulate the air volume in any one of the four chambers, providing new levels of versatility and comfort. This mattress may also be compressed for transport or storage.
FIG. 9 shows one configuration of the present invention with weights (W) simulating body parts sinking into the outer cover ( 91 ) and into the foam core ( 92 ) surface (FS 1 ). The coil spring core ( 93 ) is supporting the foam, but if some air is withdrawn through valve ( 94 ) and through distancing element ( 95 ), the foam surface will become softer and contour the weights more so. In contrast, the coil section will also compress and become firmer giving the mattress extra support.
FIG. 10 shows the same configuration as in FIG. 9 but with one weight removed (W1), the valve ( 104 ) is closed, and the foam core ( 102 ) and surface (FS 1 ) exhibit the imprint of the users body, as the foam core ( 102 ) recovers slowly upwards.
On the other hand the coil core ( 103 ) when air is removed from outer chamber ( 101 ) through valve ( 104 ) and distancing element ( 105 ) will be compressed and offer more upward support.
It is also possible to evacuate additional air from this mattress structure, and observe the imprint of the user's body remain on surface (SF 1 ), hence exhibiting no upward recovery.
FIG. 11 a , shows a foam coil combination mattress in its compressed and deflated state with one or more valves ( 110 ) ( 111 ) fitted onto the chamber wall and one or more air permeable distancing elements to prevent clogging. Valve ( 110 ) is larger than valve ( 111 ) and may be used for rapid inflation whereas valve ( 111 ) may be used to modulate the mattress combination as well as to inflate it.
FIG. 11 b , shows the same foam coil combination mattress in its inflated state with one or more inflation valves ( 110 ) ( 111 ) and one or more air permeable distancing elements ( 112 shown only) to prevent clogging.
While the description of the patent dwells at length on different applications in mattresses, other applications are not excluded, such as seats of all sorts, cushioning in all forms as well as any other application requiring a support apparatus for the enhancement of comfort and versatility. | The invention modulates the air-volume in both mattress-type foam and traditional coil spring cores interactively, obtaining a wide variety of levels of density and indentation force deflection (IFD or spring-back force). Foam core modulation is used to soften or harden the upper surface of the combined two elements to form enhanced-comfort support surfaces. The combinations include multiple chambers of which at least one is filled with self-inflating foam. In most configurations of the present invention, the chambers are completely sealed and are not air communicable with each other. Each chamber is fitted with a valve used to selectively withdraw air from it—but never to pressurize it by adding air forcibly. The combinations of core layers include traditional coil spring cores that may or may not be completely enclosed in their own enclosure. When air is extracted from a self-inflating foam core, its surface softens uniformly, density increases while its IFD value drops. When air is extracted from a layer containing traditional coil springs, however, the surface hardens and the IFD value increases, because the compressed coils want to spring back to their original relaxed position. The invention takes advantage of the unique interactive behavior of self-inflating foam and coil spring constructions to create multiple levels of comfort for one or more users of the same device. It is intended for all types and forms of support apparatuses, such as mattresses, seats and cushions. | 0 |
FIELD OF THE INVENTION
This invention relates to a process for the suppression of 3,3,3-trifluoropropyne during the manufacture of fluorocarbons, including fluoroolefins, and hydrochlorofluoroolefins. More particularly, this invention is directed to a process to suppress the formation of 3,3,3-trifluoropropyne during processes for the manufacture of HCFO-1233zd(E), HCFO-1233zd(Z), HFO-1234ze(E), and/or HFO-1234ze(Z).
BACKGROUND OF THE INVENTION
This invention especially relates to improvements in the production of HCFO-1233zd(E), HCFO-1233zd(Z), HFO-1234ze(E), and HFO-1234ze (Z). As used herein, the designations 1233zd and 1234ze will be used when either the E or Z isomers, or a combination thereof, is being referred to.
These compounds have zero or low ozone depletion potential as well as low global warming potential such that they are useful and desirable as replacements for existing materials used in refrigeration, foam blowing, solvents, monomers and other applications where other fluorocarbons are currently utilized.
Methods to produce 1233zd are known in the art. See for example US Patent Publication Nos. 2012-0172636; 2012-0271069; and 2012-0271070, which describe both 1233zd and 1234ze production processes. These documents are hereby incorporated herein by reference.
A preferred embodiment for the manufacture of 1233zd is as follows:
HCC-240fa+3HF→1233zd+4HCl
which takes place in a liquid or vapor phase reaction in the absence or presence of a catalyst with large excess of HF.
Methods to produce 1234ze have also been disclosed. See for example U.S. Pat. Nos. 7,485,760 and 7,638,660 where the manufacture of 1234ze is disclosed as follows:
HFC-245fa→1234ze+HF
which takes place in the liquid or vapor phase in the presence or absence of a dehydrofluorination catalyst. These patents are hereby incorporated herein by reference.
In the above processes to produce 1233zd and/or 1234ze, the crude product is usually a mixture of both the Z and E isomers (also known as the cis and trans isomers respectively). Typical processes employ one or more purification methods, such as distillation, extraction, decantation and absorption for purifying and recovering the desired fluorolefin product. Since the reaction products include the acids HCl and HF depending on the process, there is a need to remove these acid components during the product purification and recovery process. Although the bulk removal of the acids is done by one or more purification techniques such as distillation, extraction, and/or decantation; one additional unit operation that is often used for the removal of residual acidity is absorption via strong caustic solutions, such as KOH, NaOH, or the like, at a pH of about 11 or higher.
Methods to produce 3,3,3-trifluoropropyne are also known in the art. See for example U.S. Pat. No. 7,964,759, which is hereby incorporated herein by reference. Disclosed in this patent is a method to produce 3,3,3-trifluoropropyne by contacting (Z)-1-halogeno-3,3,3-trifluoropropene with a high concentration of an organic or inorganic strong base (pH>10). Both 1233zd and 1234ze are 1-halogeno-3,3,3-trifluoropropenes; 1233zd is 1-chloro-3,3,3-trifluoropropene and 1234ze is 1-fluoro-3,3,3-tetrafluoropropene.
As stated above, 3,3,3-trifluoropropyne can be formed when compounds such as 1233zd and 1234ze are allowed to react with strong bases. In processes where the desired product is one of those listed above, trifluoropropyne is usually considered to be an undesired impurity due to both potential toxicity and flammability concerns and accordingly, this compound is preferably removed if it is formed. The need for the removal of trifluoropropyne necessarily increases capital investment as well as operational costs associated with production of one or more of the above compounds. Therefore, it would be much more desirable to not form trifluoropropyne in the first place. Hence, there is a need for means by which the formation of trifluoropropyne can be avoided.
This invention provides a solution to this problem.
SUMMARY OF THE INVENTION
As shown above, 3,3,3-trifluoropropyne can be formed when crude products of 1233zd and/or 1234ze are allowed to react with a strong caustic solution. Since it is known that reaction with a strong base solution can promote the formation of trifluoropropyne, a process that does permit such a reaction, should either eliminate or reduce the formation of trifluoropropyne.
The method disclosed here is different from traditional fluorocarbon/fluoroolefin processes where unrecoverable amounts of HF and/or HCl in the crude product containing one or more of 245fa, 1234ze, 1233zd, or other intermediates in the manufacture of said compounds, is typically treated with water to remove the bulk of the acid followed by absorption of residual HF and/or HCl in a circulating caustic scrubber system (containing aqueous solution of NaOH, KOH, etc.) and finally drying the water-saturated deacidified crude product with molecular sieves and/or concentrated sulfuric acid.
In one embodiment, the crude product containing unrecoverable amounts of HF (and/or very minor amounts of HCl) is treated with water in a first HF absorber with once through water (or circulating weak HF solution) to remove the bulk of the acid. This stream would then be treated in a second absorber with once-through water to remove further amounts of acid. The essentially acid free stream which may contain trace amounts of HF would then be optionally cooled to selectively condense water to reduce the amount of moisture followed by drying/HF absorption in a circulating H 2 SO 4 absorption system. Concentrated sulfuric acid provides a very effective means of drying fluorocarbons/fluoroolefins and, in addition, has a high affinity for HF. In addition, the sulfuric acid that is used for drying and trace HF absorption can be regenerated by means known in the art and reused in the process.
In this embodiment, the need to use a caustic scrubber is eliminated, thereby reducing the cost associated with supplying caustic to the process and the disposal of spent caustic (an aqueous mixture of caustic plus halide salts). In addition, there is a cost avoidance advantage since the prior art need to remove trifluoropropyne is eliminated.
In another embodiment, the crude product containing unrecoverable amounts of HF (and/or very minor amounts of HCl) is treated with water in a first HF absorber with once through water (or circulating weak HF solution) to remove the bulk of the acid. This stream would then be treated in a second absorber with circulating weak caustic solution between pH 7 and 10 (inclusive) to remove further amounts of acid. The acid free stream would then be optionally cooled to selectively condense water to reduce the amount of moisture followed by drying in a circulating H 2 SO 4 absorption system. Concentrated sulfuric acid provides a very effective means of drying fluorocarbons/fluoroolefins. In addition, the sulfuric acid that is used for drying can be regenerated by means known in the art and reused in the process.
In another embodiment, in the production of HCFO-1233zd and/or production of HFO-1234ze the crude mixture containing both isomers of HCFO-1233zd (E and Z isomers) and/or HFO-1234ze (E and Z isomers) is first separated via distillation or other means known in the art such as extraction to recover a highly purified E isomer and a stream that is substantially Z isomer. Note, this stream may contain some E isomer but the highly purified E isomer stream should not contain more than ppm amounts of Z isomer.
Distillation is a particularly suitable method for the separation of these isomers due to boiling point differences between the E and Z isomer. For example, the boiling point of (E)-1233zd is about 19° C. while the boiling point of (Z)-1233zd is about 38° C. and the boiling point of (E)-1234ze is about −19° C. while the boiling point of (Z)-1234ze is about +9° C. The stream containing the E isomer (also known as trans isomer) could then be subjected to either the methods disclosed above, i.e., HF absorption followed by a substantially caustic-free solution which includes water and/or a weak caustic solution (pH 10 or less); or treated in the conventional manner using HF absorption followed by brief exposure to a caustic solution of any practical strength, eg., less than 4% NaOH solution.
It should be appreciated by those persons having ordinary skill in the art(s) to which the present invention relates that any of the features described herein in respect of any particular aspect and/or embodiment of the present invention can be combined with one or more of any of the other features of any other aspects and/or embodiments of the present invention described herein, with modifications as appropriate to ensure compatibility of the combinations. Such combinations are considered to be part of the present invention contemplated by this disclosure.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention as claimed. Other embodiments will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein.
BRIEF DESCRIPTION OF THE DRAWINGS
Various non-limiting schemes are shown to illustrate the invention.
FIG. 1 shows a general scheme in the vapor phase for recovering a product with no trifluoropropyne formation.
FIG. 2 shows a liquid phase scheme for deacidification with water followed by phase separation of the organic layer from the aqueous HF layer. The organic layer is then dried by passing it through a tower filled with a desiccant. The desiccant, when properly chosen, will both remove moisture and trace amounts of HF that may remain in the organic layer.
FIG. 3 shows a liquid phase scheme for deacidification with water followed by phase separation of the organic layer from the aqueous HF layer. The organic layer is then contacted with concentrated sulfuric acid to absorb moisture and trace HF.
FIG. 4 shows a liquid phase scheme for deacidification with water followed by phase separation of the organic layer from the aqueous HF layer. The organic layer is then vaporized and contacted with concentrated sulfuric acid to absorb moisture and trace HF.
FIG. 5 shows a process for the manufacture of 1233zd with one of the embodiments of the invention herein described.
DETAILED DESCRIPTION OF THE INVENTION
A description of one embodiment of the invention follows using a continuous 1233zd process as the example for illustration with vapor phase deacidification. This embodiment is shown in FIG. 5 .
Step (1)—produce 1233zd from 240fa and excess HF by the reaction:
240fa+3HF→1233zd+4HCl
Step (2)—recover HCl and recycle intermediates and unreacted starting materials including 240fa and HF. Treat the crude 1233zd (in the vapor state) which contains HF in a water absorber using multiple stages or multiple absorbers to remove the bulk of the HF. Optionally cool the resulting vapor stream such that a portion of the water is condensed but the crude 1233zd is not condensed.
Step (3)—feed the cooled crude 1233zd (in vapor state) into a sulfuric scrubber which is circulating a concentrated sulfuric acid solution to remove both the water and any residual HF. The resulting stream which is essentially free of moisture, HF and 3,3,3-trifluoropropyne may be subjected to distillation steps to further purify the 1233zd.
The above process may also be used in a process to produce 1234ze from 245fa with no trifluoropropyne formation.
Alternative Embodiments
Referring to FIG. 2 , a liquid phase deacidification process may also be used wherein liquid crude may be contacted with water in batch mode or in continuous mode in a single or multiple stages ( FIG. 1 shows a single stage). After each stage, the organic material would be phase separated from the aqueous phase.
In another alternative embodiment, again referring to FIG. 2 , continuous extraction may be used for this step. The resulting crude material which is saturated with water and trace HF may then be treated with a desiccant such as silica gel, molecular sieves or alumina which is also effective for removal of HF.
Referring to FIG. 3 , the liquid crude organic may be contacted with concentrated sulfuric acid followed by phase separation (or in an extraction column).
Referring to FIG. 4 , in yet another alternative method, the liquid crude organic may first be vaporized and fed to a circulating sulfuric scrubber as described in step 5 above.
EXAMPLE 1
1233zd is produced via the methods described in the specification of US Patent Publication No. 2012-0172636, which is hereby incorporated herein by reference. The crude product contains a maximum of about 50 ppm 3,3,3-trifluoropropyne.
The crude product exiting the reactor is subjected to HCl recovery and HF recovery to recover a stream with the following composition:
Component
wt %
1233zd (E)
85.4%
1233zd (Z)
4.0%
Other organic
7.3%
impurities
HCl
0.1%
HF
3.2%
3,3,3-trifluropropyne
<50 ppm
The temperature of the feed stream is approximately 46° C. and the pressure is approximately 10 psig.
The above stream is fed to an HF Absorber which has a supply of once-through fresh water feed at ambient temperature (approximately 25° to 30° C.). The HF Absorber is packed with random packing and has sufficient theoretical stages for absorbing at least 99% of the incoming HF. The amount of water is adjusted to produce a nominal 5% solution of aqueous HF as well as supply sufficient wetting of the packing. The stream exiting the HF absorber, which is saturated with water, is cooled to in order to condense some portion of the water. The resulting stream is continuously fed to a sulfuric acid dryer to remove the remaining moisture and trace HF. The sulfuric acid dryer consists of a pump tank which is initially filled with 99+ wt % H 2 SO 4 connected to a packed tower. A pump is used to circulate the H 2 SO 4 from the pump tank to the top of the packed tower while the process stream flows upwards.
The stream exiting the top of the sulfuric acid dryer is analyzed and found to contain no additional 3,3,3-trifluoropropyne.
EXAMPLE 2
99.9% pure 1233zd(E) was passed through a scrubber (dimensions of the scrubber column: 6 inch diameter, 10 foot height) circulating dilute NaOH solution at pH 10. The feed rate of 1233zd(E) was maintained at 1-2 lbs/hr. The product exiting the scrubber was passed through a Drierite (CaSO 4 ) drier and sampled. No 3,3,3-trifluoropropyne was observed in the collected samples.
EXAMPLE 3
Example 2 was repeated except the pH of circulating solution was about 8. Again, as in Example 2, no 3,3,3-trifluoropropyne was observed in the collected after scrubber and drier samples.
COMPARATIVE EXAMPLE 1
1233zd was produced via the methods described in the specification of US Patent Publication No. 2012-0172636, the disclosure of which is hereby incorporated herein by reference. The crude product contains a maximum of about 50 ppm 3,3,3-trifluoropropyne.
The crude product exiting the reactor had the following composition:
Component
wt %
1233zd (E)
32.2%
1233zd (Z)
1.5%
Other organic
2.8%
impurities
HCl
39.9%
HF
23.6%
3,3,3-trifluropropyne
<40 ppm
The organic composition in the above is the same as in Example 1. What differs is the amount of HF and HCl because the reaction product was not subjected to HCl and HF recovery. The wt. percent of the composition of the stream exiting the reactor represented in the above Table is based on about 4.4 moles of organics (average molecular weight about 140 g/mole), about 18.5 moles of HCl, and about 20 moles of HF.
The stream exiting the reactor was passed through a continuous caustic scrubber column. A 10% KOH solution was continuously circulated through the column at about 50° to 65° C. to remove excess of HF and HCl by-product. Acid free crude product that exited the scrubber column was then dried using Drierite (CaSO 4 ). The crude product exiting the drier was analyzed and the concentration of 3,3,3-trifluoropropyne was found to be from 0.4 wt % to 0.7 wt %.
COMPARATIVE EXAMPLE 2
1233zd is produced via the methods described in the specification of US Patent Publication No. 2012-0172636, the disclosure of which is hereby incorporated herein by reference. The crude product contains a maximum of about 50 ppm 3,3,3-trifluoropropyne.
The crude product exiting the reactor is subjected to HCl recovery and HF recovery to recover a stream with the following composition:
Component
wt %
1233zd (E)
85.4%
1233zd (Z)
4.0%
Other organic
7.3%
impurities
HCl
0.1%
HF
3.2%
3,3,3-trifluropropyne
<40 ppm
The temperature of the feed stream is approximately 46° C. and the pressure is approximately 10 psig.
The above stream is fed to a circulating caustic scrubber which has an initial concentration of 4 wt % NaOH. The stream exiting the circulating caustic scrubber, which is saturated with water, is cooled to in order to condense some portion of the water. The resulting stream is continuously fed to a sulfuric acid dryer to remove the remaining moisture. The sulfuric acid dryer consists of a pump tank which is initially filled with 99+ wt % H 2 SO 4 connected to a packed tower. A pump is used to circulate the H 2 SO 4 from the pump tank to the top of the packed tower while the process stream flows upwards. The stream exiting the top of the sulfuric acid dryer is analyzed and found to contain from about 800 to 2000 ppm 3,3,3-trifluoropropyne.
As used herein, the singular forms “a”, “an” and “the” include plural unless the context clearly dictates otherwise. Moreover, when an amount, concentration, or other value or parameter is given as either a range, preferred range, or a list of upper preferable values and lower preferable values, this is to be understood as specifically disclosing all ranges formed from any pair of any upper range limit or preferred value and any lower range limit or preferred value, regardless of whether ranges are separately disclosed. Where a range of numerical values is recited herein, unless otherwise stated, the range is intended to include the endpoints thereof, and all integers and fractions within the range. It is not intended that the scope of the invention be limited to the specific values recited when defining a range.
It should be understood that the foregoing description is only illustrative of the present invention. Various alternatives and modifications can be devised by those skilled in the art without departing from the invention. Accordingly, the present invention is intended to embrace all such alternatives, modifications and variances that fall within the scope of the appended claims. | This invention relates to a process for the suppression of 3,3,3-trifluoropropyne during the manufacture of fluorocarbons, fluoroolefins, hydrochlorofluoroolefins. More particularly, this invention is directed to a process to suppress the formation of 3,3,3-trifluoropropyne during processes for the manufacture of HCFO-1233zd(E), HCFO-1233zd(Z), HFO-1234ze(E), and/or HFO-1234ze(Z). | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to circuits for the generation of step digital signals from binary signals of a very high bit rate.
2. Description of the Prior Art
The optimum use of the capacity of a transmission channel requires adaption of the signal to be transmitted to the signal/noise ratio in the transmission channel and to the band width of the channel. If a coaxial cable is employed as the transmission medium, then the path attenuation is approximately proportional to the square root of the signal frequency. Thus, with increasing transmission band width, the signal/noise ratio decreases quite quickly. The optimum exploitation of a digital signal is possible when the signal is transmitted not in binary form, but rather in the form of a signal with a plurality of amplitude steps, a socalled multi-step signal. As a rule, the number of steps selected for such signals is chosen so that the channel capacity becomes a maximum as the product of the resultant signal/noise ratio and the band width.
Circuits known in the art for the generation of such multi-step signals from binary inputs generally employ the technique of weighted addition, making use with very high bit rate inputs, in the range of at least a few hundred Mbit/s difficult.
Circuits known in the art employing the technique of weighted addition of binary signals encounter special difficulties with binary signal inputs in this range. At such a bit rate, exact weighting becomes difficult and the elimination of feedback so as not to affect the addition is also a problem. Circuits useable with lower bit rates can, therefore, not be readily adapted to use with bit rates in the hundred Mbit/s range.
SUMMARY OF THE INVENTION
A circuit for the generation of digital signals from a high bit binary input with a high degree of accuracy generates 2 2 -step digital signals from n-binary input signals. Such generation is inventively achieved by use of first and second multi-emitter transistors each having n emitter connections. The base connections of the two multi-emitter resistors are connected to a reference potential through a common resistor. The collector connections of each of the multi-emitter transistors are also connected to the reference potential, however, such connections are separately made through respective resistors. The collector connection of the first multi-emitter transistor is connected to an output, and the emitter connections of both multi-emitter transistors are respectively connected both with an operating voltage through a current source, as well as with the output connection of one of n emitter followers connected to the signal inputs. The emitters of the second multi-emitter transistor are also respectively connected to n emitter followers each connected with a signal input. The signal input to the n emitter followers connected to the second multi-emitter transistor is the inverse of the signal connected to the n emitter followers connected with the first multi-emitter transistor.
Each emitter connection of the multi-emitter transistors is respectively connected to a current source which provides a current which is 2 n-1 times an initial current value, where n is the respective number associated with each emitter of the multi-emitter transistors.
A second embodiment of the invention dispenses with transistor current sources and utilizes a series of high ohmic resistors as current sources having resistance values which are stepped in powers of 2.
It is accordingly an object of the present invention to provide a circuit of the type described which combines a very low feedback of input signals with a weighting having minimal imprecision which is useable with binary inputs in any range, including the range of several hundred Mbit/s.
It is another object of the present invention to provide a circuit of the type described which is composed only of transistors and resistors, thereby facilitating production using integrated circuit technology.
Another object of the present invention is to provide a circuit of the type described which is adaptable for use with other logic circuitry in which the most positive potential of the binary input signal is allocated to the logical one state.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a circuit for the generation of 2 n -step digital signals from n binary input signals constructed in accordance with the principles of the present invention.
FIG. 2 is an embodiment of the circuit of FIG. 1 for the generation a four-step digital signal from two binary input signals, utilizing resistors for current sources.
FIG. 3 is a graphic representation of possible inputs for the circuit of FIG. 2, and the corresponding output.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
A circuit for the generation of 2 n -step digital signals from n-binary signals is illustrated in FIG. 1. The circuit contains a first multi-emitter transistor T1 and a second multi-emitter transistor T2. The base connections of T1 and T2 are connected, and are connected to a reference voltage V r through a common resistor R1. The collector of transistor T1 is connected to the reference voltage V r through a resistor R2, and the collector of the transistor T2 is connected to the reference voltage V r through a resistor R3.
Each of the multi-emitter transistors T1 and T2 has n emitters. The first emitter connection for transistor T1 is designated 11, and the last emitter connection for transistor T1 is designated n1. The first emitter connection for the transistor T2 is designated 12, and the last emitter connection for that transistor is designated n2.
Each of the n emitters of both transistors T1 and T2 are connected to an operating voltage -UB through respective current sources. Emitters 11 and 12 are connected to the voltage -UB through current sources supplying a current I s . Each subsequent emitter of both the transistors T1 and T2 is connected to the operating voltage -UB through a current source supplying current of a magnitude 2 n-1 I s . This much of the circuit of FIG. 1 represents a base-coupled differential amplifer with current sources.
In addition, each of the emitter connections of both the transistors T1 and T2 are connected to the emitters of preconnected emitter followers, one follower for each emitter of the transistors T1 and T2.
As shown in FIG. 1, the emitter follower associated with the emitter 11 of the transistor T1 is designated T3, and has an input signal E1 supplied to the base of the transistor T3, and a collector connected to the reference voltage V r . The emitter n1 of the transistor T1 is connected to an emitter follower T5 which has an input En supplied to its base, and which also has a collector connected to the reference voltage V r .
Similarly, the emitter 12 of the transistor T2 is connected to an emitter follower T4, which has an input E1 supplied to its base. The input E1 is the inverse of the input E1. The collector of the emitter follower T4 is also connected to the reference voltage V r . The emitter n2 of the transistor T2 is connected to an emitter follower T6, which has an input En supplied to its base, and a collector connected to the reference voltage V r .
A weighting of the input signals stepped according to powers of 2 is thus produced by means of the current sources I s through 2 n-1 I s connected to each emitter. Thus, the first input signal is weighted with 2 0 I s current, or simply I s , and the n th input signal is weighted with the 2 n-1 I s current. The weighted emitter currents of the two multi-emitter transistors appear at the respective collector connections, reduced by the base current, which in this case is negligible. An output is provided at A from the collector of T1.
A second embodiment of the circuit of FIG. 1 is shown in FIG. 2, utilizing only two binary input signals to form a four-stage output signal which can be utilized as the transmission signal for input to a coaxial cable path. The circuit contains two multi-emitter transistors T11 and T12 connected together in the manner of a base-coupled differential amplifier. The common base connection is connected to a reference voltage V r through a resistor R11, and the respective collectors of transistors T11 and T12 are connected to the reference voltage V r through resistors R12 and R13.
Four emitter followers are pre-connected to the emitter connections of the two multi-emitter transistors T11 and T12. The emitter follower T13 has a base input E1, and a collector connected to the reference voltage V r , and the emitter follower T15 has a base input E2, and also has a collector connected to the reference voltage V r .
The emitter follower T14, connected to the emitter of the transistor T12 has a base input E1 and a collector connected to the reference voltage V r . An emitter follower T16 has a base input E2 and a collector connected to the reference voltage V r . As in FIG. 1, the inputs E1 and E2 are respective inverses of the signals E1 and E2.
In place of the current sources as shown in FIG. 1 which are connected to the emitters of the multi-emitter transistors, the embodiment of FIG. 2 utilizes resistor pairs which are correspondingly dimensioned, designated R14 and R15, and R16 and R17. As an example, the resistors R14 and R15 may have resistance values of 200 ohms, and the resistors R16 and R17 may have resistance values of 100 ohms so that the corresponding emitter currents of I and 2I result. The only requirement is that the resistor values for R16 and R17 be one-half of the values for R14 and R15.
For matching to a coaxial cable connected to an output A, the resistors R12 and R13 may be 75 ohms, and resistor R11 may be 8.7 kohm.
Operation of the circuit of FIG. 2 will be described utilizing the inputs E1 and E2 as graphically shown in FIG. 3. Inputs E1 and E2 are not shown in FIG. 3, however, it will be understood that those inputs are simply respective inverses of E1 and E2. It is assumed that the more positive potential in the binary input signals corresponds to the logical one state. The four-step transmission signal can thus assume the values 0, 1, 2 and 3, with the more positive potential allocated to the higher value. As shown in the lower portion of FIG. 3 with the output A plotted on the ordinate and time plotted on the abscissa. For the inputs shown in FIG. 3, operation of the circuit of FIG. 2 is such as to provide an output of 0 Volt for the value 3, and the values 2, 1 and 0 are represented by more negative potentials.
In describing the operation of the circuit of FIG. 2, let it be first assumed that both input signals E1 and E2 are in a logical zero state. Thus, both emitters of the multi-emitter transistor T11 are at a comparatively negative potential, so that both emitters of that transistor are conducting. Because the inputs E1 and E2 to emitter followers T14 and T16 are the inverse of signals E1 and E2, both emitters of the multi-emitter transistor T12 are non-conducting.
The currents thus added at the collector of the multi-emitter transistor T11 represent the maximum current through this resistor, so that lowest potential, corresponding to the value logical zero, is generated at the collector resistance R12.
If the input signal level E1 now changes to a logical one value, then the smaller of the two emitter currents of the multi-emitter transistor T11 is blocked. A more positive potential which corresponds to the value logical one then arises at the collector of this transistor. Moreover, an emitter of the multi-emitter transistor T12 is now also conductive, since E1 is at a value of logical zero. Charges in the base zone of the transistor T11 allocated to the current I are directly transmitted to the base zone of the transistor T12 upon this change-over process, so that there follows a very quick change-over of the current from one emitter of the transistor T11 to the corresponding emitter of the transistor T12. This quick change-over of the emitter currents is made possible by the fact that saturation of the transistors T12 and T11 is avoided.
If, after a change-over of the input signals, the first input signal E1 is at the value logical zero and the second input signal E2 is at the value logical one, then the larger emitter current of the transistor T11 is transmitted to the transistor T12. The potential at the collector at the transistor T11, in contrast to the preceding case, now becomes more positive and the value logical two occurs at the output.
If both input signals are at the value logical one, then the transistor T11 is completely non-conducting and the potential at the collector connection of this transistor now has its most positive value corresponding to an output signal of a value logical three.
For the compensation of varying amplification properties which may result if the multi-emitter transistors have not been specially selected, it is possible to reduce or increase the emitter resistors serving as current sources as may be required. It is also possible to tap the inverse output signal from the collector connection of the second multi-emitter transistor, T2 or T12, for driving further symmetrical differential amplifiers.
Although modifications and changes may be suggested by those skilled in the art, it is the intention of the inventor to embody within the patent warranted hereon all changes and modifications as reasonably and properly come within the scope of the inventor's contribution to the art. | This invention is a circuit for the generation of 2 n -step digital signals from n-binary signals which are respectively supplied to the input of emitter followers which are connected with a first multi-emitter transistor, whereas inverse binary signals are respectively supplied to the input of another set of emitter followers which are connected to a second multi-emitter transistor. The emitter connections of both multi-emitter transistors are also respectively connected through stepped current sources to an operating potential. The base connections of the multi-emitter transistors are connected to a reference potential through a common resistor. The collector connections of the multi-emitter transistors are connected to load resistors and serve as output connections. The circuit is particularly suited as a binary multi-stage converter for employment in PCM systems of a very high bit rate. | 7 |
CROSS-REFERENCE TO RELATED APPLICATION
This application claims the benefit of U.S. Provisional Patent Application Ser. No. 60/504,718 filed Sep. 22, 2003, which is hereby incorporated herein by reference in its entirety for all purposes.
TECHNICAL FIELD
The present invention relates generally to sterile covers or drapes for surgical microscopes that act as a sterile barrier between the microscope and a sterile operative field.
BACKGROUND OF THE INVENTION
Surgeons in operating rooms around the world perform simple and complex surgical procedures with the use of surgical microscopes. Many of these procedures require the use of ultra small micro instruments, devices, and medical supplies. In addition, surgeons conducting these procedures are operating on extremely delicate and microscopic patient anatomy. Many of these operations could not be performed without the use of magnification—or microsurgery. As surgery typically must be conducted in a “sterile field,” and because the surgical microscopes are complex instruments that would be difficult to sterilize effectively for each procedure, microsurgery typically requires that the microscope be covered or “draped” with a sterile, pliable drape. This drape serves as sterile barrier between the microscope and the patient, and protects the sterile field by allowing a surgeon who is wearing sterile surgical gloves and gowns to position the microscope over the patient without contaminating himself or the patient and sterile field. The drape also protects the surgical microscope against contamination via the transfer of bacteria, viruses, and other potentially infectious microbes from a patient to the external surfaces of the microscope. The typical surgical microscope is a costly instrument with a useful life of many years and is routinely used to conduct surgery on thousands of patients, thus making protection against contamination to the patient or patient to the microscope important.
The general shape or pattern of a typical surgical microscope drape is that of a rectangular or otherwise configured flexible sheet of material with extremities designed to fit over the optics of a variety of surgical microscope designs. As the rectangular shape is held up vertically, the top short side of the rectangle is open, the long sides of the rectangle are enclosed, and the bottom short side is enclosed with a fitting for an objective lens housing and transparent non-magnifying lens cover. Prior to sterilization, the drape is systematically folded in such a manner as to allow a person dressed in sterile gloves and gown to pull the open end of the drape over the surgical microscope. The lens cover is then fitted onto the objective lens or front lens of the microscope. Generally, the objective lens points down toward the sterile field and is the component on the microscope that is closest to the patient. Because of the close proximity of the objective lens to the patient and the sterile field, it is the component most likely to act as a conductor and/or transmitter of contamination and/or infection.
The main components of a surgical microscope include the microscope body, which houses the optics; the floor stand, ceiling, or wall mount from which the optics are suspended; and the light source. As the light source is activated, illumination is directed through the objective lens to illuminate the desired subject at a distance that is determined by the focal length (e.g., f=300 mm) or working distance of the objective lens or variable lens system of the microscope body. An image of the illuminated subject is reflected back through the objective lens and is then projected to the eyes of the microscope user via an optical pathway in a system of prisms, mirrors, and lenses in the microscope body, binoculars, and eyepieces.
However, as illuminating light passes through the objective lens, it is not uncommon for some of the light to be reflected by the drape's lens cover, creating glare. This glare may result in the creation of chromatic and spherical aberrations for the user or may block the field-of-view entirely. There have been various attempts at solutions that would resolve this problem but none are completely effective.
An attempted solution pursued by some surgical microscope users is to remove the sterile lens cover that covers the objective lens from the drape. However, this attempted solution allows a non-sterile lens to be close to the sterile field or a patient's open incision. Contamination of a surgeon's instruments is likely if any instrument inadvertently touches the exposed non-sterile objective lens of the microscope. In addition, high-speed drills are often utilized in microsurgery that cause the uncontrolled displacement of bodily fluids or bone chips up towards the unprotected objective lens of the microscope. The clinical and health risks of this attempted solution are evident.
Another attempted solution has been to create a sterile microscope drape with a “dome-shaped” objective lens cover. The purpose of the dome is to reduce refracted light. However, the properties of curvature in this type of design compromise the magnifying performance of the microscope—performance for which microscope manufacturers have strived mightily to achieve and end-users have paid handsomely to acquire. In addition, certain sterilization processes through which some drapes are subjected have been known to leave condensation on the inside of a convex lens as the drape cools down after sterilization. Regardless of whether the dome is convex or concave in nature, neither design completely eliminates chromatic or spherical aberrations or undesirable glare. The result is that users of dome drapes must force their eyes to accommodate aberrations caused by the design. This can expedite and increase eyestrain and fatigue and may even cause headaches in some users. Aside from the optical shortcomings of dome covers, end users of this design continue to complain about unwanted glare or continue to compromise aseptic technique by removing the sterile dome-shaped objective lens cover.
Yet another attempted solution offered by a surgical microscope manufacturer involves removing the sterile lens cover from the drape and installing a sterile slanted lens cover. The slanted lens has proven to be very effective at completely eliminating the unwanted glare described heretofore. However, this methodology produces other undesirable issues: (1) the slanted lens must be sterilized every time it is used. This redundant process is expensive and inconvenient when personnel labor and sterilization costs are calculated, (2) the slanted lens itself is proprietary and is not inexpensive, (3) given the rigors of the operating room environment, a reasonable likelihood exists that the lens may become lost or broken, (4) there is a possibility that the person installing the sterile slanted lens prior to each procedure may become contaminated when interfacing with the non-sterile microscope body.
And finally, an attempted solution has emerged which utilizes a sterile microscope drape that includes a slanted lens cover. The housing of the slanted lens cover is inserted onto the bottom of the microscope objective lens during the microscope draping process and is held in place by friction. However, due to the lens angle necessary to eliminate unwanted glare, the drape of the objective lens housing is excessively tall and presents additional challenges for compact packaging. In addition, sterile microscope drapes currently in use worldwide typically do not utilize a tall objective lens housing but rather a low-profile housing. So the height of this tall slanted lens cover housing reduces the working distance (the distance from the surgical site to the bottom of the objective lens) available to the surgeon. As predetermined and precise working distances are important to surgeons, this proposed solution can be cumbersome and generally is not practical for many types of modern microsurgery. In addition, the requirement for a specialized drape of this sort can present availability and cost problems not present when standard drapes are used.
Accordingly, it can be seen that needs exist for improvements to surgical drapery and/or microscopes to eliminate or at least significantly reduce the glare experienced by microscope users without compromising microscope optical performance, sterility, or surgeon technique. It is to the provision of such a solution that the present invention is primarily directed.
SUMMARY OF THE INVENTION
The present invention includes an adapter device that semi-permanently attaches to a surgical microscope for the purpose of allowing any standard low profile microscope drape (flat lens or dome-shaped lens) to be utilized without the occurrence of unwanted glare. This device preferably covers the outside of the microscope's objective lens as opposed to being attached to the bottom of the lens. It can be attached to the outside of the objective lens either by set screws that grasp the outside of the objective lens casing, via the ultra fine recessed threads that already exist above the objective lens on the inside of the microscope bodies of some microscope manufacturers, by a clamp that slides over the outside ring of the objective lens and is tightened with tension inducing or clamping screws, or by an insert and twist design that also exists inside the microscope bodies of some manufacturers. The adapter device holds a standard low-profile drape objective lens cover housing in an angled or slanted orientation relative to the scopes objective lens, and thereby eliminates unwanted glare without the cumbersome tall housing associated with drape products having a built-in slanted lens cover. As a multitude of flat lens cover drape products are on the market today, availability and cost concerns are minimized. And the optical integrity of the microscope magnification, clarity, depth-of-focus, working distance and resolution are not significantly compromised by the invention, while glare is eliminated or at least reduced. Furthermore, the invention allows optimal optical performance without compromising aseptic or individual surgeon technique.
In one aspect, the invention is a device for use with a surgical microscope and a sterile drape for performing surgery on a patient, the surgical microscope having an objective lens and the drape having a cover lens. The device comprises a first part for attaching to the surgical microscope, a second part for attaching to the sterile drape, and a body between the first part and the second part, wherein the body is configured to dispose the drape cover lens in general alignment with and at an angle relative to the microscope objective lens to eliminate or reduce glare on the objective lens without significantly reducing available workspace between the cover lens and the patient.
In another aspect, the invention is a system for creating a sterile barrier for a surgical microscope for performing surgery on a patient, the microscope having an objective lens. The system comprises, a sterile drape having a cover sheet with an aperture, a peripheral frame in the aperture, and a cover lens in the frame. Additionally, the system comprises an adapter having a first part for attaching to the surgical microscope, a second part for attaching to the sterile drape, and a body between the first part and the second part, wherein the body is configured to dispose the drape cover lens in general alignment with and at an angle relative to the microscope objective lens to eliminate or reduce glare on the objective lens without significantly reducing available workspace between the cover lens and the patient.
In another aspect, the invention is a combination of a surgical microscope having an objective lens and an adapter attached to the surgical microscope adjacent to the objective lens. The adapter has an angularly offset body in which a drape mounted onto the adapter is held with a lens cover portion of the drape oriented at an acute angle relative to the objective lens of the microscope.
In still another aspect, the invention is a method of reducing or eliminating the glare in the surgical microscope, in which a sterile drape is attached to the microscope with an angularly-offset adapter that holds a lens cover portion of the drape at an acute angle relative to an objective lens portion of the microscope.
And in another aspect, the invention is an adapter for reducing glare in a surgical microscope, in which a first coupling for a removable attachment to the surgical microscope is adjacent an objective lens portion thereof. The invention also has a second coupling for removable engagement with a sterile drape having a lens cover portion. The adapter has an angularly-offset body in which the first coupling and the second coupling are oriented at an angle of between about fifteen to about twenty-two degrees relative to one another.
These and other aspects, features and advantages of the invention will be understood with reference to the drawing figures and detailed description herein, and will be realized by means of the various elements and combinations particularly pointed out in the appended claims. It is to be understood that both the foregoing general description and the following brief description of the drawings and detailed description of the invention are exemplary and explanatory of exemplary embodiments of the invention, and are not restrictive of the invention as claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an exploded elevational view of a portion of a surgical microscope, a portion of a sterile microscope drape, and an adapter according to a first exemplary embodiment of the present invention.
FIG. 2 is a front elevational view of the adapter of FIG. 1 .
FIG. 3 is a cross sectional view of the adapter taken at line A—A of FIG. 2 .
FIG. 4 is a rear perspective view of the adapter of FIG. 1 .
FIG. 5 is a front perspective view of the adapter of FIG. 1 .
FIG. 6 is a plan view of the adapter of FIG. 1 .
FIG. 7 is a left elevation view of the adapter of FIG. 1 .
FIG. 8 is a perspective view of the adapter taken at line B—B of FIG. 7 .
FIG. 9 is a left elevation view of an adapter according to a second exemplary embodiment of the present invention.
FIG. 10 is a plan view of the adapter of FIG. 9 .
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
The present invention may be understood more readily by reference to the following detailed description of the invention taken in connection with the accompanying drawing figures, which form a part of this disclosure. It is to be understood that this invention is not limited to the specific devices, methods, conditions or parameters described and/or shown herein, and that the terminology used herein is for the purpose of describing particular embodiments by way of example only and is not intended to be limiting of the claimed invention. Also, as used in the specification including the appended claims, the singular forms “a,” “an,” and “the” include the plural, and reference to a particular numerical value includes at least that particular value, unless the context clearly dictates otherwise. Ranges may be expressed herein as from “about” or “approximately” one particular value and/or to “about” or “approximately” another particular value. When such a range is expressed, another embodiment includes from the one particular value and/or to the other particular value. Similarly, when values are expressed as approximations, by use of the antecedent “about,” it will be understood that the particular value forms another embodiment.
Referring now to the drawing figures, FIGS. 1–8 show an adapter device 10 according to a first exemplary embodiment of the present invention. FIG. 1 depicts the adapter 10 used in conjunction with a surgical microscope 12 and a sterile drape 14 for performing surgery on objects. Conventional surgical microscopes 12 have a body 16 with an objective lens 18 in a lens casing 20 . Typical surgical microscopes 12 with which the adapter 10 may be used include the M500+ series microscopes by LEICA MICROSCOPY SYSTEMS, LTD. of Switzerland, the Opmi Sensera and Opmi Pentera microscopes by CARL ZEISS, INC., as well as many other scopes made by various manufacturers. Conventional drapes 14 have a cover sheet 22 with an aperture, a peripheral frame 24 secured in the aperture, and a non-magnifying transparent lens cover 26 mounted in the frame. Typical drapes 14 with which the adapter 10 of the present invention can be used include CLEAR IMAGE drapes by BUYMD, INC. of Atlanta, Ga. (additional information online at buymd dot net), as well as many other drapes sold by various other sources.
The adapter 10 comprises a first end 28 with a first fitting for attaching to the surgical microscope 12 . For example, the fitting may be provided by an internally threaded flange 30 ( FIG. 4 ) for mating with threads on the casing 20 of the surgical microscope 12 . In alternative embodiments, the first fitting includes set screws that grasp the outside of the objective lens casing, an insert-and-twist design, a clamp design, and/or another screw-on design with threaded mating components. It will be understood that the invention is intended to include various other first fitting designs that permit semi-permanent attachment to conventional surgical microscopes so that the adapter can be removed for replacement or cleaning but is secured firmly in place on the microscope for repeated use with a number of drapes that are attached and detached without compromising the secureness of the attachment of the first fitting.
The adapter 10 further comprises a second end 32 with a second fitting for attaching to the sterile drape 14 . For example, the fitting may be provided by a snap-tight fitting 34 having an external ridge and/or notch for mating with an internal ridge and/or notch in the cover lens frame 24 of the drape 14 . In alternative embodiments, the second fitting includes an insert-and-twist design, a clamp design, a screw-on design, another snap-tight fitting, and/or another friction fitting. In other alternative embodiments, the adapter second fitting and the drape lens frame are keyed for use together. For example, the adapter second end may have a tab and the drape lens frame may have a notch that receives the tab (or vice versa). In this manner, the manufacturer and the practitioner can ensure that the intended drape is used with a given model of microscope, to avoid compatibility and/or performance problems, or to prevent the use of inferior grades of drapes with the adapter. It will be understood that the invention is intended to include other second fitting designs that permit quick attachment to and detachment from conventional drapes so that a drape can be easily and securely installed on the adapter for use and then easily be removed from the adapter after use, so that another drape can be installed for the next procedure.
Furthermore, the adapter 10 comprises a body portion 36 between the first end 28 and the second end 32 . As seen in FIG. 3 , the body 36 is configured to orient the drape cover lens 26 in general alignment with and at an acute angle 38 relative to the microscope objective lens 18 , to eliminate or reduce glare on the objective lens without significantly reducing available working distance between the lens cover and the subject on which surgery is being performed. Preferably, the angle 38 between second end 32 and the first end 28 is between about 15 degrees to about 22 degrees, and more preferably about 18.5 degrees. Alternatively, the adapter 10 may be provided with an angle 38 that is greater or smaller, depending on the particular microscope, drape, user, and/or surgical procedure to be performed.
The adapter 10 can optionally also include a flat section or recess 40 defined in the body 36 as seen in FIG. 4 . The recess 40 facilitates removing the drape 14 from the adapter 10 by providing a spot for the user to access and grasp or press against the frame 24 of the drape. Preferably, the recess 40 is generally flat or concave and positioned on the thicker side of the body 36 , thereby permitting good access to the frame 24 . In this way, the user can position a thumb or other finger in the recess 40 and against frame 24 to easily “pop” the frame off of the adapter.
Referring now to FIGS. 9–10 , there is shown an adapter device 110 according to a second exemplary embodiment of the present invention. In this embodiment, the first end 128 has a first fitting provided by a clamp 132 that slides over the outside casing of the objective lens of a microscope, and can then be tightened with tension-inducing or clamping screws 130 , a wing-nut, thumb-screw, or other coupling. In further alternative embodiments, the invention comprises a surgical microscope having an adapter permanently or removably mounted adjacent its objective lens, the adapter having an angularly offset body, such that a drape installed on the adapter is held with its lens cover oriented at an acute angle relative to the objective lens.
In use, the adapter of the present invention is installed on the microscope by engaging the first fitting onto the microscope in a semi-permanent or permanent manner. A drape 14 is mounted onto the second fitting of the adapter. After a surgical procedure is performed, the drape is removed by detaching the drape from the second fitting, and is disposed of. A fresh drape is installed for each procedure, whereas the adapter preferably remains in place on the microscope.
Accordingly, it can be seen that the present invention provides a number of benefits over known surgical drapery and/or microscopes. In particular, the adapters of the present invention eliminate or at least significantly reduce the glare experienced by microscope users. In addition, these adapters accomplish this benefit without compromising microscope optical performance or surgeon technique.
While the invention has been described with reference to preferred and example embodiments, it will be understood by those skilled in the art that a variety of modifications, additions and deletions are within the scope of the invention, as defined by the following claims. | An adapter that attaches to a surgical microscope for holding the lens cover of a sterile drape at an angle relative to the scope's objective lens, so as to eliminate the reflection (glare) of illumination off the drape lens cover as light is directed through the surgical microscope to the field of view at the patient surgical site. | 0 |
BACKGROUND OF THE INVENTION
The invention relates to a method for priming a substrate by contacting the substrate with a primer fed from a primer source and depositing the primer on the substrate. The invention also relates to a process for the coating of a substrate by contacting the substrate with a primer fed from a primer source, depositing the primer on the substrate, and coating the primed substrate with a coating substance.
There are several methods of improving the adhesion between a substrate and its coating. These methods can be surface treatment, mechanical roughening, removing weak boundary layers, minimising stresses, using adhesion promoters, using suitable acid-base interactions, as well as providing favourable thermodynamics and using wetting. Typical treatment techniques include the use of chemicals such as primers and solvents, the use of heat and flame, mechanical methods, plasma, corona treatment and radiation. Each technique can have several effects that improve adhesion.
An important method of improving the adhesion between a substrate and its coating is priming. Priming means the treatment of a substrate with a primer. A primer means a prefinishing coat applied to surfaces that are to be painted or otherwise finished. See McGraw-Hill Dictionary of Scientific and Technical Terms, 6 th Ed., p. 1668 and 1669.
Typical primers are adhesive organic substances which are soluble in water and/or an organic solvent and are used for treating the substrate surface in order to improve its adhesion or bonding to the coating. In the following table, typical primers and their adhesion and performance characteristics are given.
TABLE 1
Properties of typical primers
Adhesion Characteristics
Performance Characteristic
Plastic
Heat
Moisture
Chemical
Type of primer
Paper
Metal
film
Resistance
Resistance
Resistance
Shellac
Poor
Excellent
Poor
Poor
Poor
Poor
Organic Titanate
Good
Good
Good
Fair
Fair
Fair
Polyurethane
Very good
Excellent
Excellent
Excellent
Excellent
Excellent
Polyethyleneimine
Very good
Good
Excellent
Excellent
Poor
Poor
Ethylene Acrylic
Excellent
Excellent
Fair
Fair
Excellent
Good
Acid
Polyvinylidene
Excellent
Fair
Excellent
Good
Very good
Fair
Chloride
Traditional priming takes place by conventional solution application techniques. The application of a primer promotes adhesion between the substrate and the coating by increasing the free energy (wettability) of the surfaces, inducing chemical reaction between them, and removing bond weakening impurities from them.
However, traditional priming has the drawback that it is difficult to achieve the correct coating weight suitable for the specific primer to be used. Uniform deposition is important for all primers. This is especially the case with uneven surfaces, the less available sites of which are poorly reached by conventional priming techniques.
SUMMARY OF THE INVENTION
These drawbacks have now been overcome by a new method for priming a substrate by contacting the substrate with a primer fed from a primer source and depositing the primer on the substrate. The claimed method is essentially characterized in that the deposition is carried out electrostatically. By deposition is meant the application of any material to a substrate. By electrostatically is meant something pertaining to electricity at rest, such as an electric charge on an object. See McGraw-Hill, Dictionary of Scientific and Technical Terms, 6.sup.th Ed., p. 707.
Electrostatic coating methods are known per se. However, the inventors found that these methods are especially suitable for priming purposes. By means of electrostatic coating, the correct coating weight suitable for any specific kind of primer can easily be achieved. Additionally, less available sites on uneven substrate surfaces are conveniently reached by the electrostatic priming techniques. Thus, a larger part of the substrate surface will possess improved primer-induced adhesion.
Electrostatic coating methods can be divided to three methods: electrostatic spraying and electrospinning, typically from solution under DC field, as well as dry coating from powders using AC fields.
In the spraying process, a high voltage electric field which is applied to the surface of a liquid causes the emission of fine charged droplets. The process is governed by mass, charge and momentum conservation. Therefore, there are several parameters, which influence the process. The most important parameters are the physical properties of the liquid, the flow rate of the liquid, the applied voltage, the used geometry of the system, and the dielectric strength of the ambient medium. The essential physical properties of the liquid are its electrical conductivity, surface tension and viscosity. An electrospray apparatus is typically formed of a capillary, pressure nozzle, rotating nozzle, or atomizer, which feed the coating liquid, and a plate collector which carries the substrate to be coated. An electrical potential difference is connected between the capillary and the plate.
The potential difference between the plate and the end of the capillary supplying the coating liquid is several thousands volts, typically dozens of kilovolts. The emitted droplets are charged and they may be neutralized if necessary by different methods. Their size varies, depending on the conditions used. The most suitable electrospraying conditions for priming are discussed in more detail below.
Electrospinning, just as electrospraying, uses a high-voltage electric field. Unlike electrospraying which forms solidified droplets, solid fibers are formed from a polymer melt or solution, which is delivered through a millimeter-scale nozzle. The resulting fibers are collected on a grounded or oppositely charged plate. With electrospinning, fibers can be produced from single polymers as well as polymer blends.
Electrospinning can be used to produce ultra-fine continuous fibers, the diameters of which range from nanometers to a few micrometers. The small diameter provides small pore size, high porosity and high surface area, and a high length to diameter ratio. The resulting products are usually in the non-woven fabric form. This small size and non-woven form makes electrospun fibers useful in variety of applications.
In a spinning process various parameters affect the resulting fibers obtained. These parameters can be categorized into three main types, which are solution, process and ambient parameters. Solution properties include concentration, viscosity, surface tension, conductivity, and molecular weight, molecular-weight distribution and architecture of the polymer. Process parameters are the electric field, the nozzle-to-collector distance, and the feed rate. Ambient properties include temperature, humidity and air velocity in the spinning chamber. The most suitable electrospinning conditions for priming are discussed in more detail below.
Dry coating is quite similar to the electrospraying and electrospinning processes, with the exception that the raw material is in powder form. One of the latest inventions is to coat paper with this method. Paper coating by dry coating method is an alternative method for the traditional pigment coating. This dry surface treatment (DST) of paper and paperboard combines the coating and calandering processes. In the DST process, the electrically charged powder particles are sprayed onto the surface of the paper or paperboard. The particles form a layer on the surface of the paper and attach to the paper by electrostatic forces. The final fixing which is made in a nip between heated rolls, provides adhesion and makes of the surface smooth.
In the following, the most important technical features of the invention are disclosed. The claimed process relates to the electrostatic priming of a substrate. Preferably the substrate to be primed is a solid material, such as wood, paper, textile, metal, plastic film, or a composite material. A preferred type of substrate is cellulose or wood containing <300 g/m 2 of non-coated or coated garde produced by means of normal wet paper processes. Most preferably, the solid material is paper. By paper is meant any felted or matted sheet containing as an essential part cellulose fibers.
The electrostatic deposition used in the claimed priming is according to one preferred embodiment electrospraying. In the electrospraying, the primer is preferably initially in the form of liquid droplets dispersed in the gas phase. The droplets may be either droplets of molten primer or, preferably, droplets of a solution of the primer material in a solvent. Typically, the average diameter of the liquid droplets is between 0.02 and 20 μm, preferably 0.05-2 μm.
According to another preferred embodiment of the invention, the claimed priming by electrostatic deposition is electrospinning. In the electrospinning, at least a part of the primer is in the form of fibers dispersed in the gas phase. The fibers may be formed either from molten primer or, preferably, droplets of a primer solution in a solvent. When forming the primer fibers by electrospinning, the average diameter of the fibers is preferably between 0.05 and 5.0 μm, most preferably between 0.1 and 0.5 μm.
The claimed electrostatic priming may also be a mixture of electrospraying and electrospinning, where both solid droplets and solid fibers are formed on the substrate.
When using electrostatic deposition (spraying, spinning, or both) from solution, the primer material content of the solution is preferably between 5 and 50% by weight, most preferably between 20 and 45% by weight. The solution is preferably between 40 and 400 cP, most preferably between 50 and 200 cP. The solvent is selected according to the primer applied, considering also that its volatility must be low enough for good productivity and its conductivity must be suitable for the electrostatic process. Preferred solvents are water and water/alcohol systems.
As was said above in connection with the general description of the invention, the primer material may be a native polymer, a polyalcohol, an organometal compound, and/or a synthetic polymer. Typically, the primer material is a synthetic polymer (homo- or copolymer). According to one advantageous embodiment of the claimed invention, the synthetic polymer is an acrylic copolymer, which most preferably is in the form of an aqueous emulsion. Then the deposited material thickness is typically 0.002-0.05 g/m 2 , preferably 0.006-0.02, and most preferably about 0.01 g/m 2 . According to another advantageous embodiment of the invention, the primer is diethanol aminoethane (DEAE), preferably in aqueous medium. Then, the preferred thickness of the deposited material is 0.02-0.5 g/m 2 , more preferably 0.06-0.2, and most preferably about 0.1 g/m 2 .
Most preferably, the primer solution also contains an additive to modify the morphology of the primer particles on the substrate. A preferred additive is a polymer soluble in the solvent and compatible with the primer, which has a sufficiently high molecular weight to stabilize the process. Preferably, the polymeric additive has to be suitable for the electrostatic process as well. Examples of polymers suitable as additives in the claimed electrostatic processes are among others polyvinyl alcohol, polyethylene oxide, and acrylic resins.
The electrostatic primering of the instant invention is preferably carried out by means of an apparatus suitable for either electrospraying or electrospinning. It consists of a fume chamber with minimised interference, in which a construction comprising a metal plate for supporting the substrate and a feed section are arranged. A voltage source is coupled to the metal plate and the feed section. The electrostatic force expressed as the voltage divided by the distance between the substrate and the primer source raised to the second power is according to one embodiment between 0.02 and 4.0 V/mm 2 , preferably between 0.2 and 0.5 V/mm 2 . The electrostatic voltage is preferably between 10 and 50 kV, more preferably between 20 and 40 kV, and the distance between the primer source and the substrate is preferably between 100 and 1000 mm, more preferably between 200 and 500 mm.
In addition to the above described method for priming a substrate electrostatically, the invention also relates to a process for coating a substrate by contacting the substrate with a primer fed from a primer source, depositing the primer on the substrate, and coating the primed substrate with a coating substance. Said deposition of the primer on the substrate is carried out electrostatically.
The claimed coating process thus comprises said electrostatic priming followed immediately or later by a coating process. For the priming step, the same specifications apply as above, so, there is no reason to repeat them here. However, when moving on from priming to coating, the primed substrate is preferably flame or, most preferably, corona treated before it is coated with the coating substance.
Typically, the coating substance is a thermoplastic resin. As the most advantageous substrate was paper, a preferred combination is the coating of paper with said thermoplastic resin. The best thermoplastic resin is a polyolefin resin such as an ethylene polymer (homo- or copolymer).
DESCRIPTION OF THE FIGURES
The Figures which will be referred to are:
FIG. 1 which shows an electrospinning apparatus according to one embodiment of the invention.
FIG. 2 which shows the feed section of the electrospinnig apparatus according to FIG. 1 .
FIG. 3 which shows the seed section and the collector plate of the electrospinning apparatus according to FIG. 1 .
FIG. 4 which shows a SEM of paper coated with P1 with a magnification of 3500×, left with the coating weight 0.1 g/m 2 , right with the coating weight 0.01 g/m 2 .
FIG. 5 which shows a SEM of paper coated with P2 with a magnification of 750×, left: with coating weight 0.1 g/m 2 , right: with coating weight 0.01 g/m 2 .
FIG. 6 which shows a SEM of paper coated with P3 with a magnification of 750×, left with the coating weight 0.1 g/m 2 , right with the coating weight 0.01 g/m 2 .
FIG. 7 which shows a SEM of paper coated with P5 with the magnification 1500×, left with the coating weight 0.1 g/m 2 , right with the coating weight 0.01 g/m 2 .
FIG. 8 shows a SEM of paper coated with P6 with the magnification 1500×, left with the coating weight 0.1 g/m 2 , right with the coating weight 0.01 g/m 2 .
FIG. 9 shows a SEM of paper coated with P7 with the magnification 3500×, left with the coating weight 0.1 g/m 2 , right with the coating weight 0.01 g/m 2 .
FIG. 10 shows a SEM of paper coated with P11 with the magnification 3500×, left with the coating weight 0.1 g/m 2 , right with the coating weight 0.01 g/m 2 .
FIG. 11 shows a SEM of paper coated with P12 with the magnification 1500×, left with the coating weight 0.1 g/m 2 , right with the coating weight 0.01 g/m 2 .
FIG. 12 shows a SEM of paper coated with P13 with the magnification 1500×, left with the coating weight 0.1 g/m 2 , right with the coating weight 0.01 g/m 2 .
FIG. 13 shows the PE-film coating after a peel test, P1-P13 with corona treatment.
FIG. 14 shows the paperboard with P3 after the peel test. Left without corona treatment and right with corona treatment.
FIG. 15 shows the paperboard with P5 after the peel test. At left without corona treatment and at right with corona treatment.
FIG. 16 shows the paperboard with P6 after the peel test and with corona treatment. The magnification was 1500×.
FIG. 17 shows the paperboard with P7 after the peel test and without corona treatment. The magnification was 1500×.
FIG. 18 shows SEM pictures after the peel test and without corona treatment; at left paperboard with P11, magnification 3500×; in the middle paperboard with P12, magnification 1500×; and at right paperboard with P13, magnification 1500×.
FIG. 19 shows the PE-film coating after the peel test without corona treatment, P1-P13.
FIG. 20 shows the critical surface energies of primers (P1-P13) and paperboard (K).
FIG. 21 shows the critical surface energies of primed paperboard.
FIG. 22 shows adhesion measurement results.
FIG. 23 shows the adhesion with primers (P1-P13).
FIG. 24 shows surface energy values (geometric mean) and adhesion of primers.
FIG. 25 shows surface energy (geometric mean) and adhesion, where the priming weight was 0.01 g/m 2 .
FIG. 26 shows surface energy (geometric mean) and adhesion, where the priming weight was 0.1 g/m 2 .
FIG. 27 shows the particle size distribution of primer layers.
DETAILED DESCRIPTION
In the following, the invention is exemplified by a few examples, the procedures of which are described more closely below.
In this experimental work, priming was made with an electrospinning apparatus as illustrated in FIG. 1 . The apparatus includes a fume chamber, the walls of which, except the front side wall, are constructed of metal plate, to minimise the external and internal electrical interference. The inner wall surfaces are covered with glass fiber composite. The used power supply unit is a high-voltage supply of type BP 50 Simco. The power supply can produce both positive and negative 0-50 kV voltage.
The apparatus also includes a feed section having a spinneret and a needle. The needle is attached to the spinneret which is made of glass with luer (mikä on luer?) junction and the power supply is connected to the metallic junction of the needle. The feed section is illustrated in FIG. 2 .
As a counter-electrode to the feed section a square copper plate is arranged, the size of which is 400 mm×400 mm×1 mm. This collector plate, which supports the substrate, is hung on a plastic stand. The collector plate and the feed section is illustrated in FIG. 3 . To the front of the collector plate is attached the substrate to be coated. The substrate can be, for example, a metal folio, a paper, or a non-woven textile. In the experiments carried out, the substrate was paper of quality CTM ion-coated 225 g/m 2 wood free board of chemical pulp.
Suitable primers were selected by a preliminary test. Then, these primers, called P1-P13, were tested for solution viscosity (Brookfield DV-II+), morphology (JEOL SEM T-100), surface energy (PISARA-equipment), and adhesion (Alwetron peel test). The effect of a corona treatment of the primed paper substrate on the adhesion was also carried out.
13 primers, i.e. P1-P13, were tested. The symbols P1-P13 mean:
P1→Carboxyl methyl cellulose
P2→Alkyl ketene dimer
P3→Polyethylene amine
P4→Polyvinyl amine
P5→Polyvinyl alcohol
P6→Emulgated acrylic copolymer
P7→Ethylene copolymer
P11→Polyvinyl alcohol modified with ethylene groups
P12→Diethanol aminoethane (DEAE)
P13→MSA/C 20 -C 24 -olefin
B→C 20 -C 24 olefin
C→ethylene copolymer
E→Polyvinyl amine
G→polyvinyl acetone
H→Dicthand aminoethene (DEAE)
I→carbonyl methyl cellulose
The results were as follows.
Results and Discussion
The Primer's Suitablility to Electrospraying or -Spinning
The proper solution contents of primers and process parameters were found by experimentation. Several solution contents of each primer were tested. All primers were sprayed or spun through a 5 cm long needle, the size of which was 18 G.
Primers P5, P6 and P11 were especially suitable without using morphology modifying additives in the spraying/spinning solution. Primers P1, P2, P3, P7, P12, and P13 were also especially suitable, but they needed additives. Without additives they formed large droplets, and the coated areas were very small. With additives, coated area enlarged significantly and droplet size diminished.
The Productivity of the Electrospraying or -Spinning
The productivities for each primer are presented in Table 2. In the table are presented also other properties, which are used for calculating the rate of application, namely the specific weight of the solution, the primer content of the solution, and the primer consumption. Also the needed priming times for dry coating weights 0.1 g/m 2 and 0.01 g/m 2 are presented in the table.
TABLE 2
Productivities and other properties of each primer
Specific
Primer
Weight of the
content of
Consumption
Needed priming time
solution
solution
of solution
Area
Productivity
For
For
Primer
[g/ml]
[%]
[s/1 ml]
[m 2 ]
[g/m 2 s]
0.01 g/m 2
0.1 g/m 2
P1
1.028
11.70
5040
0.0491
0.00049
21 s
205 s
P2
0.915
31.67
6252
0.0491
0.00094
11 s
106 s
P3
1.035
22.35
2768
0.0314
0.00266
4 s
28 s
P5
0.973
15.00
3300
0.0491
0.00090
11 s
111 s
P6
1.037
45.20
1410
0.0962
0.00346
3 s
29 s
P7
1.041
22.33
2040
0.1200
0.00095
11 s
107 s
P11
1.018
7.50
1800
0.0452
0.00094
11 s
107 s
P12
0.982
25.00
1920
0.0855
0.00149
7 s
67 s
P13
1.011
22.39
4562
0.0360
0.00138
7 s
72 s
During the consumption test, it was easy to see which ones of the primers are suitable for continuing priming and which ones are not, unless some changes are made to the solution or process. Primers P2, P3, P6, and P13 are not suitable for continuous priming, because they gel on the end of the needle. Instead, primers P1, P5, P7, P11, and P12 are suitable for continuous priming.
The needed priming times are only estimated. In productivity measurement, it was assumed that all of the primer is transferred from the needle to the collector plate. However, in practise some particles fly over the plate and some large droplets may not fly so far. During the consumption measurement, the process was at first faster and then became slower because the solution level and pressure in the needle were reduced with time. Thus the consumption values are average values. Coating areas are defined by eye, so these are also approximate values.
The Viscosity of the Primer Solutions and the Morphology of the Primed Paperboards
The viscosities of the used primer solutions were the Brookfield viscosity. The morphologies of the deposited primer particles were measured by analysing SEM pictures. The SEM-pictures presented in this chapter, were taken randomly. In addition to the viscosity and the morphology, this chapter shows further process parameters such as the voltage and the working distance between the substrate and the feeding capillary.
In the following, each sample is treated separately.
Primer P1
The viscosity of the solution was 370 cP. Although the viscosity was high, primer P1 did not form fibers, but droplets. The droplet size was 0.1-0.3 μm, the voltage and working distance were ±35 kV and 350 mm, respectively, and the diameter of the coated area was 25 cm. A SEM of the layer of P1 is presented in FIG. 4 .
Primer P2
The viscosity of the solution was 170 cP. Again, although the viscosity was sufficiently high, the primer did not form fibers, but droplets. The droplet size was 0.5-6 μM, the voltage and working distance were ±30 kV and 450 mm, respectively, and the diameter of the coated area was 25 cm. A SEM of the layer of P2 is presented in FIG. 5 .
Primer P3
The viscosity of the solution was 215 cP. Also here, although the viscosity was sufficiently high, the primer formed droplets instead of fibers. The droplets were very large and also the size distribution was wide. The size of the droplets was 1,2-17 μm, the voltage and the working distance were ±50 kV and 350 mm, respectively, and the diameter of the coated area was 20 cm. A SEM of the layer of P3 is presented in FIG. 6 .
Primer P5
Viscosity of solution was 193 cP. Again, although the viscosity was sufficiently high, primers did not form fibers, but droplets. Droplet size was 0.2-1.5 μm, voltage and working distance were ±40 kV and 400 mm, and diameter of coated area was 25 cm. Layer of P5 is presented in FIG. 7 .
Primer P6
The viscosity of the solution was quite low: 90 cP, therefore it formed droplets. The droplet size was 0.2-5 μm, the voltage and working distance were ±30 kV and 300 mm, respectively, and the diameter of the coated area was 35 cm. Layer of P6 is see in FIG. 8 .
Primer P7
The viscosity of the solution was 60 cP. Although the viscosity was low, the primer formed also fibers besides droplets. The fiber forming is probably caused by use of additives. The fiber diameter was approximately 0.1 μm and the droplet size was 0.5-6 μm, and the voltage and working distance were ±30 kV and 400 mm, respectively. The primer coated area was very large. The primer coated the whole area of the collector plate. Layer of P7 is presented in FIG. 9 .
Primer P11
Thy viscosity of the solution was 110 cP. Primer 11 formed only thin fibers, including some pearls. The fibre diameter was 0.4-0.1 μm and the pearl size was 0.8-1.4 μM. The voltage and working distance were ±40 kV and 400 mm, respectively, and the diameter of the coated area was 24 cm. The layer of P11 is presented in FIG. 11 .
Primer P12
The viscosity of the solution was 60 cP. Although the viscosity was low, the primer formed also fibers besides droplets. The fiber formation is probably caused by the use of additives. The droplet size was 0.5-3 μm and the fibre diameter was 0.1-0.4 μm. The voltage and working distance were ±20 kV and 300 mm, respectively, and the direction of the electric field was from minus potential to plus potential. The diameter of the coated area was 33 cm. Layer of P12 is presented in FIG. 12 .
Primer P13
The viscosity of the solution was 310 cP. Although the viscosity was sufficiently high, the primer formed droplets instead of fibers. The droplet size was 0.2-2.5 μm, the voltage and working distance were ±30 kV and 250 mm, respectively, and the diameter of the coated area was 18 cm. A layer of P13 is presented in FIG. 13 .
The Surface Energy
The critical surface energies of the primers are presented in FIG. 20 . Their surface energies are compared to the surface energy of the paperboard. Surface energy values of all primers are smaller than surface energy of the paperboard. In FIG. 20 sample K means paperboard and P1-P13 primers, which was used in preliminary tests.
The critical surface energies of primed paperboard are presented in FIG. 21 . The critical surface energy values of the primed paperboard are smaller than the surface energy value of the paperboard itself. The surface energy values by geometric mean are presented in Appendix 1.
The surface energy determination was done with three liquids, which is the minimum count.
Adhesion of Primers and Priming Methods
The adhesion was measured by priming paper conventionally (primers B-I) and according to the invention (primers P1-P13), extrusion coating with LDPE, and finally measuring the adhesion force between the LDPE and the paper. The primers B-I which were primed to the paperboard by conventional spreading, are chemically similar to primers P1-P13, respectively. When priming by spreading, the obtained priming weight is higher compared to the electrostatic method (>>0.1 g/m 2 ).
Adhesion measurement results of primers B-I primed by spreading are presented in FIG. 22 . Primers B-I applied by spreading do not significantly improve adhesion. Only primer H improves adhesion, if extrusion coating is made without corona treatment.
In FIG. 23 is presented the adhesion of samples, whose priming weights are 0.1 g/m 2 and 0.01 g/m 2 . Priming is done with the electrostatic coating method. Primers P1-P13 need corona treatment for improving adhesion. When corona treatment is not used, the adhesion is zero with almost every primer. Primers P1, P6, P11, and P13 especially with coating weight 0.01 g/m 2 , and P12 especially with coating weight 0.1 g/m 2 improve the adhesion significantly. Also primer P7 with coating weight 0.01 g/m 2 and primer P2 with coating weight 0.1 g/m 2 are good adhesion promoters.
The reference in both FIGS. 22 and 23 is PE coated paperboard with corona treatment, and without the use of primer.
Each primer has a unique coating weight, which gives a maximal adhesion.
The primers were attached to the paperboard and the PE-film, when corona treatment was used with the extrusion coating. This fact is illustrated in FIG. 14 . The picture is taken after peel test on an iodine dyed surface of the PE-film. Only primers P3 and P6 with priming weight 0.1 g/m 2 have attached to the PE-film only partly.
When corona treatment is not used in extrusion coating, primers do not promote adhesion, because they do not attach to the PE-film. FIG. 15 shows the PE-film after the peel test. Some of the chemical pulp is attached to the surface of the PE, but mainly it is not attached to the PE without corona treatment.
In the following figures SEM-pictures after the peel test are presented. These SEM-pictures have been taken from the paperboard side. Thus, the pictures show the morphology changes after extrusion coating, when they are compared to the SEM-pictures, which have been taken just after the priming.
The morphology of P3 does not change if corona treatment was not used with extrusion coating. When corona treatment was used, the primer was spread on the surface of the paperboard. In FIG. 16 , the picture to the right has been taken at a point, which is not attached to the PE-film. The points where the paperboard primed with P3 is attached to the PE-film looks like the FIG. 14 .
The paperboard with primer P5 has also been attached partly to the PE-film. The picture to the right in FIG. 17 was taken at a point, where the paperboard is not attached to the PE. The morphology of the primer P5 does not significantly change during extrusion coating despite the use of corona treatment.
The morphology of primed P6 changed during extrusion coating if corona treatment was used. P6 spreads on the surface of the paperboard. FIG. 18 has been taken at a point, where there is no attachment to the PE. Probably the priming weight 0.1 g/m 2 is too much, because the paperboard with P6 is not attached properly to PE.
The morphology of P7 changes in extrusion coating significantly. The fiber is attached to the surface of the paperboard, spreads a bit, and probably absorbed ( FIG. 19 ). Instead the morphology of P8 is not significantly changed in extrusion coating ( FIG. 20 ).
The morphology of P11, P12, and P13 has changed significantly during the extrusion process ( FIG. 21 ). All of these primers are attached to the surface of the paperboard, primers have spread and probably absorbed to the surface of the paperboard.
Morphology changes during extrusion process depend on primers. Only connecting issue with primers, which is proved already in peel tests, is that corona treatment in extrusion process improves adhesion significantly.
CONCLUSIONS
This work proves that electrostatic coating methods are suitable for priming.
Improvement in adhesion is achieved compared to conventional priming by spreading. Lower priming weights give even better adhesion than higher priming weights. However, primers should preferably be corona treated in extrusion coating when coating paper with polyethylene. Adhesion results shows that every primer have a specific priming weight, which gives a maximal adhesion.
The correlation between the surface energy values and the adhesion is presented in FIGS. 24-26 . From these figures can be seen that low polarity improves adhesion.
In FIG. 27 is presented the particle size distribution of each primer layer. On the basis of the above, particle sizes affects adhesion. Thus, primer P12 has excellent adhesion properties, because it has a low proportional polarity and small particle size. Probably the effect of particle size is based on the fact that smaller particles form more adhesive spots per area onto the surface of the paperboard.
In addition to primer polarity and particle size, adhesion properties change also with different priming weights. Some primers improve adhesion better with priming weight 0.01 g/m 2 than with priming weight 0.1 g/m 2 , and others improve adhesion better with priming weight 0.1 g/m 2 .
APPENDIX 1
Surface energy values by geometric mean of paperboard,
primers P1-P14, and primed paperboards
Dispersion
Polarity
Surface
component
component
Proportional
energy
[mJ/m 2 ]
[mJ/m 2 ]
polarity
[mJ/m 2 ]
Paperboard
21.26
0.02
0.001
21.28
P1
20.96
31.41
0.600
52.37
P2
22.03
22.72
0.508
44.75
P3
22.49
21.73
0.491
44.22
P4
22.8
20.35
0.472
43.14
P5
22.99
29.35
0.561
52.34
P6
25.37
8.36
0.248
33.73
P7
26.56
6.65
0.200
33.21
P8
28.27
8.64
0.234
36.92
P9
23.27
21.78
0.483
45.05
P10
24.39
9.38
0.278
33.77
P11
24.52
25.75
0.512
50.27
P12
25.27
8.74
0.257
34.01
P13
18.53
13.87
0.428
32.4
P14
19.81
21.35
0.519
41.16
Primed 0.01 g/m 2
P1
21
2.08
0.090
23.08
P2
20.96
1.97
0.086
22.93
P3
23.17
0.33
0.014
23.49
P5
22
0.96
0.042
22.96
P6
21.84
1.19
0.052
23.03
P7
20.78
1.5
0.067
22.27
P11
23.14
0.69
0.029
23.83
P12
22.83
0.09
0.004
22.93
P13
22.64
0.61
0.026
23.25
Primed 0.1 g/m 2
P1
23.75
0.45
0.019
24.2
P2
22.62
0.1
0.004
22.73
P3
23.45
0.02
0.001
23.47
P5
21.37
1.02
0.046
22.39
P6
21.66
0.5
0.023
22.17
P7
23.99
0.39
0.016
24.38
P8
21.34
1.71
0.074
23.06
P11
23.71
0.23
0.010
23.94
P12
22.89
0
0.000
22.9
P13
19.92
0.17
0.008
20.09 | The invention relates to a method for priming a substrate by contacting the substrate with a primer fed from a primer source and depositing the primer on the substrate. Compared to other priming methods, the claimed priming gives better results because the deposition is carried out electrostatically. | 3 |
REFERENCE TO RELATED APPLICATIONS
This application is related to applicant's earlier applications Ser. No. 255,477, filed Apr. 20, 1981 and now abandoned, and Ser. No. 342,450, filed Jan. 25, 1982, which was passed to issue Sept. 9, 1983.
BACKGROUND AND SUMMARY OF THE INVENTION
This invention relates to balancing systems for making repetitive balance corrections on rotary elements of machines that undergo variations of balance during normal operation and where an imbalance is corrected by remote control while such elements are rotating. More particularly the present invention relates to improvements in the control of such balancing systems.
The above identified two patent applications disclose a new and improved unbalance compensator which is unencumbered by limitations of prior unbalance compensators. The new and improved unbalanced compensator comprises a plurality of balancing chambers arranged circumferentially around the body of the compensator in a symmetrical fashion. Balancing mass is transferred between opposite chambers by creating a temperature differential between fluids contained in the respective chambers. The temperature differential gives rise to a higher vapor pressure in a warmer chamber creating vapor flow through a transfer tube to an opposite cooler chamber where the transferred vapor condenses. The port ends of each transfer tube are located in their respective chambers in such a manner as to prevent liquid fluid from entering and passing through the tube into an opposite chamber whether the compensator is rotating or stopped at any particular angular position. Thus the liquid fluid is essentially restricted to the chambers while only vapor is allowed to move between chambers. The creation of a temperature difference between fluids in opposing chambers may be by either a heating means, a cooling means, or a combination of both.
The above identified two patent applications disclose various types of controls for controlling the heating and cooling chambers for the purpose of performing balance corrections. One form of control employs a heating coil for each chamber. The heating coils are selectively energized. One mode of selective energization is by transmitting power to a selected heating coil through a corresponding slip ring and brush, each heating coil being connected to a corresponding slip ring and brush. In another form of control the slip rings and brushes are replaced by stationary and rotating coils (power and signal coil pair) which are coupled via transformer coupling. Electrical power is transmitted across an air gap via power coils and the appropriate heating coil is selected by means of a signal coupled across the air gap between signal coils. Appropriate electronics are used to encode the signal for transmission and to decode the signal at reception so that the correct heating coil is energized for correcting imbalance. Vibration indicative of imbalance is monitored by a vibration pick-up provided as input information to the electronic control. Phase information as to the angular position of imbalance is also provided as an input to the electronic control by means of a shaft position encoder. The electronic control acts upon this input data to energize the appropriate heating element for creating the required balance mass transfer to correct the imbalance.
The present invention is directed to a new and improved arrangement for the control of an unbalance compensator. One advantage of the present invention is that the electronic control circuitry does not have to be mounted on the rotating mass yet the transmission of electrical power to the heating coils can be accomplished via transformer type action. By removing any electronics from the rotating mass a number of advantages accrue. One advantage is that the separate packaging of the electronics in a module unique to the rotating balance mass can be eliminated. This saves on manufacturing complexities and service considerations. Another advantage is that the electronics can be removed from potential exposure to elevated temperatures. A certain amount of temperature rise may be due to the heat generated by the heating coils for the chambers. If the ambient temperature is also extremely high, the combined effect could give rise to the possibility of spurious operation and/or malfunction of the electronics due its thermal sensitivity. While a package may be designed with insulation and safeguards to protect it against this possibility, removal of the electronics from the rotating mass provides a very desirable alternative in many instances.
A further feature of the invention is that the compensator may be made more compact. Hence it can be used in applications where it might otherwise be impossible or, where extensive modification or rework would be required to a machine to be balanced. Furthermore, manufacturing and assembly considerations for the unbalance compensator are simplified.
In one embodiment the unbalance compensator of the present invention may comprise individual primary and secondary coils for each chamber heating coil. In one species of this embodiment the primary coils may be of a uniform diameter and arranged axially adjacent each other. The secondary coils are of a uniform diameter slightly larger than that of the primary coils and are also disposed axially adjacent each other with each being in axial alignment with the corresponding primary coil. The invention allows the appropriate heating coil to be energized with efficiency and without any significant loss occurring due to leakage to other coils.
In another embodiment of the invention the primary and secondary coils may be constructed as sets of concentric rings concentric with the axis of rotation. Each primary coil confronts the corresponding secondary coil. This arrangement is compact in the axial direction allowing the overall axial dimension of the compensator to be reduced. This is important in accommodating the application of the unbalance compensator to certain types of balance mass requirements.
In still another embodiment of the invention power and signal are transmitted as a composite waveform through electromechanical connections at opposite ends of the rotating mass. These electromechanical connections comprise circular ball stud elements at the axis of rotation at the opposite ends of the rotating mass. Each ball stud is seated in a conically tapered seat formed at one end of a bushing which is resiliently biased against the ball stud. One electromechanical connection is to one side of the line voltage and the other is to the opposite side of the line voltage. One ball stud is part of a module which is mounted concentric with the axis of the unbalance compensator and is of a smaller diameter than the overall diameter of the unbalance compensator. This module contains electronic circuitry and solid state relays. The composite waveform applied via the two electromechanical connections is monitored by the electronic circuitry. The electronic circuitry decodes the signal information to select an appropriate solid state relay. The selection of a solid state relay causes the electrical power component of the composite waveform to be applied to the appropriate heating coil. This embodiment eliminates the use of slip rings and brushes, and it does not require the use of transformer coupled coils on the rotating and non-rotating portions.
The foregoing features, advantages and benefits of the invention, along with additional ones, will be seen in the ensuing description and claims which should be considered in conjunction with the accompanying drawings. The drawings disclose a preferred embodiment of the invention according to the best mode contemplated at the present time in carrying out the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an axial view, semi-schematic in nature, illustrating an unbalance compensator embodying principles of the present invention and with portions removed.
FIG. 2 is a sectional view on an enlarged scale taken substantially in the direction of arrows 2--2 in FIG. 1 and illustrating further detail of the unbalance compensator.
FIG. 3 is a fragmentary view taken in the direction of arrows 3--3 in FIG. 2.
FIG. 4 is a view similar to FIG. 2 illustrating another embodiment.
FIG. 5 is an electrical schematic diagram illustrating the electronic control which is associated with the unbalance compensator shown in the preceding drawing figures.
FIG. 6 is an electrical schematic diagram of a portion of the control showing further detail.
FIG. 7 is a view, semi-schematic in nature, illustrating a still further embodiment of the invention.
FIG. 8 is an enlarged view taken in circle 8 of FIG. 7 illustrating further detail.
FIG. 9 is an electrical schematic diagram illustrating a portion of the electrical control which is used in conjunction with the embodiment of FIGS. 7 and 8.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 illustrates in one embodiment of unbalance compensator 200 of the present invention. The unbalance compensator 200 comprises a main circular body 202 via which the unbalance compensator mounts on a rotary mass to be balanced. The axis of rotation is identified by the numeral 203. Mounted on body 202 are four uniformly arranged balance chambers 204, 206, 208, and 210. Opposite balance chambers are communicated by transfer tubes; transfer tube 212 for chambers 204, 208, and transfer tube 214 for chambers 206 and 210. Thus the arrangement defines two separate sealed systems, orthogonally related, one system being the chambers 204, 208 and transfer tube 212 and the other being the chambers 206, 210 and the transfer tube 214. Each sealed system contains balance mass fluid.
Associated with each chamber is a heater element. The heater elements are identified as 216 for chamber 204, as 218 for chamber 206, as 220 for chamber 208 and as 222 for chamber 210. Each heater element is a heating coil wrapped around the corresponding chamber so that when energizing current flows through the heating coil heat is transferred to the balance mass fluid within the corresponding chamber. By selective energization of the heater elements, this creates a temperature differential between opposite chambers with the balance mass fluid vaporizing and the vapor transferring via the transfer tube to the opposite cooler chamber where it condenses. By controlled selective energizing of the heater elements the balance mass may be distributed in such a manner as to provide balance for the entire rotating mass so as to correct for any detected imbalances. This much of the unbalance compensator 200 is identical to the corresponding unbalance compensator disclosed in the above two prior patent applications.
FIG. 2 illustrates further detail of the unbalance compensator 200. Electric power for energization of the respective heater elements is provided via sets of electromagnetic coils. These coils are arranged concentric with the axis 203. They are arranged as a series of primary coils 224 and a series of secondary coils 226. There are four coils in each series and each individual coil is identified by the corresponding base reference numeral, 224 or 226, followed by a unique literal suffix. Thus a pair of coils 224a, 226a constitute a set of coupled coils for one of the heating; coils 224b, 226b, another set forth another of the heatings coils; etc. For example, the set 224a, 226a, may be for coil 216; the set 224b, 226b, for the coil 218; the set 224c, 226c, for the coil 220; and the set 224d, 226d for the coil 222. Each set of coils has the two coils confronting each other. The series of coils 226 are mounted on the body of the unbalance compensator for rotation with the rotating mass. The series of coils 224 is stationarily mounted, for example on the associated machine frame or other suitable structure.
It will be observed that the individual coils of each series are mounted in a corresponding annular frame of U-shaped cross section, 227 and 228 respectively, with the adjacent coils in each frame being separated by annular walls. Specifically, the construction of the frame and the separating walls is of electrical steel to provide for a particular concentration of the electromagnetic flux which is created when a coil is energized with electric current. At this point it should be mentioned that in the preferred mode of operation which will be described in detail hereinafter only one of the coils in the series 224 is energized at a given time. The flux concentration characteristic of the material forming the frame and walls is such that it provides a much closer coupling with the corresponding confronting secondary coil. In other words there is reduced leakage, or spill over, into adjacent coils which are not intended to be energized. Thus improved efficiency is obtained with this construction.
The coils of each series 224, 226 are fabricated as separate individual coils. Preferably each coil is fabricated from bondable magnet wire which is wound in a form corresponding to the shape of the particular position in the frame into which it is to be disposed. The coiled bondable magnet wire is heated in an oven so that the individual turns of wire bond together to form a unitary coil. The particular number of turns and the gage of the wire will be a function of the current, frequency and power requirements involved and these may be arrived at through conventional engineering computations.
Through the improved coupling which is obtained with the present invention a higher frequency of alternating current for energizing the heater coil may be used. This results in a still greater efficiency for it means that less copper need be used in the fabrication of the coils. Furthermore by having the coils as concentric rings confronting each other at the stationary and rotary portions, it means that the compensator may be made more compact in the axial direction. This can be a very important consideration in certain applications of the invention. For example it may mean that the invention can be applied to a given machine without the need to perform an extensive rework of the machine to accommodate the mounting of the unbalance compensator. It has been found that operating frequencies as high as 1200 Hertz can be used with great effectiveness.
Thus from the foregoing description it can be perceived that the application of energizing current to coil 224a will be effective via transformer coupling with coil 226a to energize winding 216 and similarly for energization of each remaining stationary coil with respect to its associated heating coil.
FIG. 4 illustrates another embodiment 230 of the invention. This embodiment 230 is the same as embodiment 200 except for the particular disposition of the two series of coils 224, 226. In the embodiment 230 the stationary coils 224 are arranged as a series of axially adjacent coils of uniform diameter concentric with the axis 203. The series of coils 226 is arranged as a series of individual coils axially spaced adjacent and each of a slightly larger diameter than the corresponding stationary coil. The frames for the coils are of the same electrical steel and the individual coils are preferrably fabricated in exactly the same manner.
In the embodiments of FIGS. 2 and 4, each individual coil may be viewed as disposed in its own annular receptacle of U-shaped cross section with immediately adjacent receptacles of each series sharing a common leg. Each confronting receptacle pair has the legs of the confronting U's spaced closely forming the air gap across which the magnetic flux is concentrated. Hence, a very close coupling is obtained for each pair of coils. The particular details of fabrication of the coil and receptacle structures are not especially critical and various embodiments are envisioned. A particularly convenient way to fabricate the frame for mounting the coils, in the case of the FIG. 4 embodiment is to make the end walls and the separating walls of identical metal rings. These and the coils are assembled onto a metal tube. As a coil is assembled onto the tube, it is followed by the insertion of one of these rings onto the tube. This sequence is continued for the entire assembly with the rings being secured to the tube in any suitable manner. In the case of the FIG. 2 embodiment, it would be possible to form each U-shaped receptacle as a separate annular element of U-shaped cross section and then joining these together at the common legs. Still another way might be to form or draw the frame into a shape which would provide the individual coil receptacles. These are given merely by way of examples and should not be construed as imposing limitations on the scope of the invention.
FIG. 5 illustrates an example by an electronic control 270 which is well suited for use with the unbalance compensator. Briefly, the control 270 receives input signals relating to rotation of the spindle mounted mass to be balanced and acts upon these signals to develop control signals causing application of electric power to the proper heating coils of the chambers so that the proper balance mass vapor transfer necessary to maintain precise balance occurs. The circuitry may be contained within a control unit which is located in association with the machine on which the unbalance compensator is used. None of the circuitry is mounted on the rotary mass.
One input 278 is connected to receive a vibration signal from a vibration transducer 279 which is suitably mounted on the machine to sense vibration caused by imbalance. Further inputs 280, 282 receive rotary spindle position signals. These signals are derived from a position sensor 281 which is mounted on the machine in association with the rotating spindle shaft. The purpose of position sensor 281 is to provide signals which are indicative of the instantaneous rotational position of the spindle. The sensor 281, in conjunction with a portion of the control circuit, constitute what is commonly known as a shaft position encoder. The shaft position encoder includes a signal conditioning circuit 284, a frequency divider circuit 286, and a frequency counter circuit 288.
Let it be assumed that the signal channel connected to input terminal 280 receives a waveform consisting of 16 pulses per revolution of the spindle shaft. Hence, the pulses are spaced apart at intervals corresponding to 221/2 degrees of spindle rotation. A signal conditioning circuit 284 conditions the pulse waveform into a rectangular pulse train 290. The pulse train 290 consists of individual rectangular pulses each spaced apart 221/2 degrees of spindle shaft rotation. A frequency divider circuit 286 divides the frequency of the pulse train 290 by four so that a pulse train 292 is produced in which the individual rectangular pulses are spaced apart 90° of spindle shaft rotation. The frequency divided pulse train 292 is supplied to the count input of a frequency counter circuit 288. A reset input of frequency counter 288 is connected to receive a shaft position signal supplied by sensor 281 to terminal 282. This latter signal is a pulse given one per revolution of the spindle shaft. Hence, the frequency counter 288 is reset every 360 degrees of rotation of the spindle shaft.
The frequency counter circuit has outputs 294, 296, 298, and 300. Each of these inputs is successively energized in response to pulses of the pulse train 292. If it is considered that the reset pulse occurs at the 0° position of the spindle shaft, then the signal at output 294 provides a pulse during the first 90° of rotation of the spindle shaft from the 0° position. Similarly, it will be perceived that the remaining outputs 296, 298, 300 provide successive output pulse signals during the second 90°, the third 90°, and the fourth 90° respectively of spindle shaft rotation. In this way signals appearing at the outputs 294, 296, 298 and 300 of the frequency counter circuit are effective to indicate in which quadrant of rotation the spindle shaft is at any particular instant of time.
The four output signals from frequency counter circuit 288 are supplied to corresponding inputs of a sample and hold circuit 302. The sample and hold circuit 302 also receives a further input at a terminal 304. Therefore, before circuit 302 is described in detail, it is appropriate to consider how the signal which is supplied to terminal 304 is developed.
The terminal 278 is connected to receive the vibration signal from the vibration transducer. The vibration transducer may comprise an inductance coil containing a spring-mounted magnetic mass. As vibrations are sensed, the magnetic mass oscillates in relation to the coil in such a manner that the coil provides a sinusoidal output signal whose frequency corresponds exactly to the rotational frequency of the spindle shaft and whose peak amplitude is indicative of the magnitude of vibrations. The phase of the transducer output signal is related however to the circumferential location of imbalance.
The circuit includes a preamplifier stage 306 which receives and amplifies the input signal from the vibration transducer. This amplified vibration transducer signal is then supplied to a tunable narrow band filter circuit 308. The narrow band filter circuit 308 has a tunable center frequency controlled by a tuning circuit 310. The tuning circuit receives the pulse waveform 290 and provides an output signal which is related to the frequency of the pulse waveform 290. This output signal is supplied to the narrow band filter circuit 308 to adjust the center frequency. Because the frequency of waveform 290 is indicative of spindle shaft speed, the center frequency of the narrow band filter is thereby automatically set to the spindle shaft speed. In this way, the narrow band filter circuit is continuously tuned to whatever the instantaneous spindle shaft speed happens to be. Because vibrations of interest are at the spindle shaft speed, the amplified vibration signal is passed through the filter circuit 308 to amplifier stage 312.
The amplifier stage 312 is wide band so as to provide amplification over the full range of possible vibration frequencies corresponding to variations in spindle shaft speed. The output signal of amplifier stage 312 may be considered therefore as the unbalance signal indicated by the waveform 314. The unbalance signal will be of a generally sinusoidal character having a frequency corresponding to the instantaneous rotational frequency of the spindle shaft and having a peak amplitude corresponding to the magnitude of vibrations. The information of interest insofar as the present embodiment is concerned is the phase of the zero crossing of the signal from one polarity to the other polarity, for example, from positive to negative. The phase of the vibration signal, as noted above, corresponds to the angular position of shaft imbalance. Hence, the zero crossing can be used to provide an indication of the angular position of the imbalance.
The signal 314 is therefore supplied as an input to a zero crossing detector circuit 316. The zero crossing detector looks for zero crossings of the signal from one selected polarity to the opposite polarity, and whenever that occurs, the zero crossing detector provides an output pulse signal such as the pulse 318 indicated in the drawing figure. Hence, the pulse 318 will be given once per revolution of the spindle shaft and its phase will indicate the angular location of the imbalance in the rotating mechanism.
The sample and hold circuit 302 can now be considered in detail. It comprises four output terminals 320, 322, 324, and 326 each of which corresponds to one of the inputs received from frequency counter 288. The sample and hold circuit 302 may be considered as comprising four individual sample and hold circuits each of which is associated with a corresponding input received from circuit 288 and a corresponding output 320, 322, 324, 326. The zero crossing detector pulse signal 318 is supplied to each of the four individual sample and hold circuits. The operation of circuit 302 is such that when the zero crossing pulse 318 is given, that input line which is receiving the quadrant signal from frequency counter 288 will cause the corresponding output 320, 322, 324, 326 to be energized. The individual sample and hold circuits maintain this status until the next occurrence of the zero crossing pulse 318. Hence, so long as the zero crossing pulse 318 continues to be given during a particular quadrant of rotation, then the corresponding output 320, 322, 324, 326 remains activated. Whenever the phase of the zero crossing pulse 318 changes to a new quadrant then the output 320, 322, 324 and 326 corresponding to that new quadrant is activated. A visual display 328 is connected to the outputs 320, 322, 324 and 326 to provide a visual display of which quadrant signal is being given. As will be seen, this display is useful in set-up of the system at initial installation as well as during operation.
Each of the four outputs 320, 322, 324, 326 of sample and hold circuit 302 is connected to the input of a corresponding relay circuit 342, 344, 346, 348. Each relay circuit is in turn coupled to one of the primary coils 224. The relay circuits 342, 344, 346, 348 are identical, and hence the detail of only one is shown in the drawing figure.
Therefore, considering detail of the the relay circuit 348, one can see that it comprises a solid state relay 348a which is connected to receive the corresponding electronic signal from sample and hold circuit 302 and in turn drive a mechanical relay 348b in accordance with the sample and hold signal. The electromechanical relay 348b is a double pole type. When the signal from the sample and hold circuit is such that the corresponding coil 244a is not to be energized the relay assumes a position whereby the terminal of the coil 224a connected to the relay is grounded. Because the opposite terminal of the coil 224a is also grounded, the coil is effectively short circuited. Whenever the signal from the sample and hold circuit calls for coil 224a to be energized, then the mechanical relay 348b is operated by the solid state relay 348a to a position whereby the terminal of the coil connected to the relay is coupled through to an AC power source. This causes the coil 224a to receive energizing current via the relay 348b and hence the coil 224a is energized.
The overall operation will now be apparent. At any given time, three of the four primary coils are shorted out while one of them is energized. It has been found by shorting the non-energized coils that a very significant improvement in the coupling efficiency of the energized primary coil to its secondary coil is obtained. This allows the power to be transferred across the airgap most efficiently. For example, wattages of 500 to 600 watts can be readily transferred with relatively modest coils and current levels. Furthermore, the use of high frequency alternating current (much higher than the typically available 60 Hertz live voltage) also provides an increased efficiency coupling. The reason is that inductive reactance increases with frequency thereby reducing current flows and concomitant ohmic losses in the coils. The invention therefore provides a very useful and efficient arrangement for the control of the unbalance compensator.
FIG. 6 illustrates an example of a high frequency power generator circuit 400 which can supply the high frequency energizing current for the coils 224. The circuit comprises a transformer section 402 having an input connected across a standard 60-cycle AC line. Coupled to the secondary portions of transformer 402 are rectifying stages 404 and 406, respectively. Rectifying stage 404 develops at the point indicated by the numeral 408, a positive DC level relative to ground. Rectifying stage 406 develops at the point 410 a comparable negative DC level relative to ground. The remainder of circuit 400 comprises what may be considered a chopper-type circuit which chops the respective positive and negative DC levels to develop an alternating current waveform for application to the coils 224. Unlike a conventional chopper, however, the present chopper utilizes power MOSFET devices 412 and 414, respectively. Operation of the power MOSFET devices at the desired chopping frequency is controlled by a frequency generator circuit 416 which has one set of three terminals operatively connected to the drain, source, and gate terminals of power MOSFET 412 and another set connected to the drain, source, and gate terminals of power MOSFET 414. The frequency generator circuit 416 provides signals at the desired chopping frequency to operate the power MOSFET devices in alternation so that the respective positive and negative DC levels at 408 and 410 are alternately applied to the selected one of the coils 224 which is being energized. The circuit is particularly advantageous in that it can be fabricated at a cost which is considerably less than the cost of conventional chopper circuits, and it can provide the necessary power requirements at the higher frequencies.
FIGS. 7 and 8 illustrate a still further embodiment of compensator 350. This embodiment does not require the use of primary and secondary coils for transmitting energy across an airgap between the stationary and rotating portions. Instead, it utilizes electromechanical type contact arrangements 352, 354, respectively, at opposite ends of the rotating mass.
FIG. 7 illustrates a machine 356 such as a grinding machine on which the unbalance compensator is mounted. The machine 356 by itself has a rotating spindle and typically the machine components such as the spindle shaft are electrically floating. Therefore a ground connection for the unbalance compensator is provided at the right hand end of the machine as viewed in FIG. 7 by the provision of the electromechanical contact arrangement 354. The other side of the line voltage is supplied to the unbalance compensator via the electromechanical contact arrangement 352. Mounting of the compensator to the machine provides for a grounding of certain components of the unbalance compensator to the shaft via the contact arrangement 354.
The contact arrangements 352, 354 are substantially identical and details can be seen from consideration of a detailed view of the contact arrangement 352 shown in FIG. 8. The contact arrangement comprises a ball stud 358 coaxial with the axis of rotation and forming a part of the unbalance compensator. An insulator block 360 is stationarily mounted with respect to the machine adjacent the left hand end. A conductive cantilever spring 362 supports a conductive bushing 364 from the insulator block 360 in substantial alignment with the ball stud 358. The bushing is of a generally tubular shape and the right hand end includes a conical seat 366 within which the spherical contoured head of the ball stud seats. A forceful engagement is obtained by the resilient spring force of the cantilever 362. The arrangement functions in the following manner. As the machine 356 operates, the unbalance compensator including the ball stud 358 rotates. Bushing 364 is urged into contact with the head of the ball stud thereby providing electrical continuity for current flow from the line to the unbalance compensator. A similar continuity for ground current flow is provided by the contact 354.
As can also be seen in FIG. 8, there are certain components within the unbalance compensator which provide for operation of the proper chamber heater element. A small circular cap 368 at the left hand end of the unbalance compensator to which the ball stud 358 is affixed houses these components, or modules. Wires from the ball stud connect to respective modules. These modules are identified by the reference numerals 370, 372, 374, 376 and each is associated with a respective one of the chamber heating coils. There is also a suitable connection of the line side to another module 378. The wire which leads from each module, 370, 372, 374, 376 to a respective one of the heating coils carries current to that heating coil when the module is activated. After passing through the heating coil the current returns via a ground wire suitably connected to the rotating spindle of the machine and via the contact 354 to ground. Thus, the ball stud 358 is electrically isolated from the ball stud of the arrangement 354. The module 378 contains electronic circuitry for controlling which one of the modules 370, 372, 374, 376 is activated. The circuitry which it contains is shown in FIG. 9.
FIG. 9 illustrates a portion of the control circuit which is used with the embodiment of FIGS. 7 and 8. This circuit portion is designated by the reference numeral 500, and comprises a transformer 502 which receives the AC line voltage, such as a 60 Hertz AC voltage. This AC voltage constitutes the power component of the composite waveform which is to be developed. The signal portion of the composite waveform is provided by a circuit stage 504 comprising an SCR 506 whose gate terminal is connected to receive a pulse input from a pulse generator circuit 530. The manner in which the pulse output of pulse generator circuit 530 is developed will be explained first.
Associated with pulse generator circuit 530 are a phase quadrature circuit 532 and a logic circuit 534. The logic circuit 534 comprises four individual AND logic gates 536, 538, 540, 542. The phase quadrature circuit receives the AC line signal and develops at its four outputs pulse waveforms in which the pulses are successively phased at 90° intervals. Thus each output signal of the phase quadrature circuit 532 is uniquely related to a particular 90° segment of the AC voltage.
Each AND logic gate comprises a pair of inputs one of which is connected to a corresponding one of the outputs of the phase quadrature circuit and the other of which is connected to a particular one of the outputs of sample and hold circuit 302. Thus the circuit portion 500 shown in FIG. 9 represents only a portion of the entire control, the remainder of the control being that portion of the circuit shown above the broken line 535 in FIG. 5.
The outputs of the four AND logic gates are connected in common to the input of the pulse generator circuit 530. With this arrangement the occurrence of the zero crossing detector pulse 318 will cause a particular one of the sample and hold output lines to produce an activated output indicative of the occurrence of the zero containing detector pulse. This will be coincident with a particular one of the output signals from the phase quadrature circuit and hence the corresponding AND logic gate will produce an output to the pulse generator. The pulse generator in turn produces an output pulse for switching SCR 506 into conduction. It can therefore be understood that SCR 506 is switched into conduction in accordance with the phase of the zero crossing detector pulse 118.
The circuit stage 504 includes a number of resistors, capacitors and a diode which are connected with the SCR 506 and with the secondary of transformer 502 in the manner shown in FIG. 9.
Assuming that no pulse input is being received from pulse generator 550, the stage 504 is in a condition where SCR 506 is not conductive. This means that the capacitor 508 is uncharged. The other two capacitors 510, 512 are, however, charged. Hence, the waveform appearing at point 514 relative to ground is simply a value which corresponds to the AC line voltage. When a pulse input from the pulse generator is received, SCR 506 is suddenly switched into conduction. The result is to suddenly pull the voltage at 514 through capacitor 508 to ground thereby effectively introducing a grounding spike 518 onto the waveform. The charge on capacitors 510 and 512 dumps through the resistors associated therewith and through the SCR. The circuit however quickly recovers due to the charging of capacitor 508 and hence the spike disappears with the normal sinusoidal line waveform thereafter continuing. During recovery, the capacitor 508 discharges through the three resistors and diode of circuit 504, and capacitors 510 and 512 are recharged. This results in SCR 506 being turned off. The circuit 504 remains in this condition until the next pulse input from the pulse generator.
The module 378 contains a phase quadrature circuit 550, a highpass filter and amplifier circuit 552 and four flip-flops 554, 556, 558 and 560. These are connected as illustrated in FIG. 9. Phase quadrature circuit 550 develops four respective 90° pulse waveforms each corresponding to a corresponding one of the quadrants of the 360° of the sinusoidal power waveform. Each phase quadrature signal is supplied to one input of a corresponding flip-flop circuit. The highpass filter and amplifier circuit 552 filters the sinusoidal power component from the composite signal to only pass the grounding spike pulses to the flip-flops. Depending upon which one of the quadrants of the sinusoidal waveform contains the grounding spike pulse, a corresponding one of the flip-flops will be activated. That flip-flop which is activated in turn operates the corresponding relay module 370, 372, 374, 376 to in turn energize the corresponding heating coil. If the phase of the grounding spike changes from one quadrant to another, then a different one of the heating coils is energized. It can be seen therefore that this arrangement does not require the use of the transformer-coupled coils to transmit power from a primary coil to a secondary coil.
The quadrant display readout 328 is particularly useful at the time of initial installation of the unbalance compensator on a machine. Because the control is of a closed-loop nature, it must be ensured that the feedback is of a negative, or non-regenerative, character so that the desired control takes place. Such assurance can be obtained by a procedure involving placement of deliberate imbalance at a particular angular location in relation to the defined quadrants, say for example at the common junction of quadrants three and four. If the control is properly phased, then the display on readout 128 changes back and forth between the numbers three and four. If such is not the case, then a different condition is observed on the readout display. Proper phasing is obtained by adjusting the phase of the once per revolution pulse at terminal 282. In the present embodiment the means for generation of this once per revolution pulse comprises a pin which is circumferentially positionable on the rotary shaft at 221/2 angular increments in association with the pick-up connected to terminal 282. Hence this pin may be repositioned to the appropriate one of the 16 different angular positions so that the desired response is observed on the display readout. Depending upon the particular readout display it may be necessary to perform one or several repositionings of the marker pin on the shaft before the final position is ascertained.
The invention has been shown in the foregoing description to constitute an improved unbalanced compensator control. While a preferred embodiment has been disclosed, it will be appreciated that other embodiments are contemplated within the scope of the invention. | An improved unbalance compensator control in which the distribution of balance mass fluid is controlled by selective activation of thermal devices creating thermal differentials and ensuing balance mass fluid re-distribution for balance correction, and in which electrical power for the thermal devices is transmitted across an air gap separating stationary and rotating portions by means of the selective energizing of primary coils each of which has a corresponding confronting secondary coil associated therewith. Different geometries of coils are disclosed. In another embodiment a composite waveform containing power and signal components is conducted to the rotating portion by electro-mechanical contact arrangements at opposite axial ends of the machine on which the unbalance compensator is mounted. | 6 |
CROSS-REFERENCE TO RELATED APPLICATION
This application claims priority to European Patent Application No. 11160509.3, filed Mar. 30, 2011, which is incorporated herein by reference.
FIELD
The disclosure relates to modernizing an elevator installation
BACKGROUND
Elevator installations for conveying persons and goods have been known for a long time and are customary. Since elevator installations are relatively long-term capital-cost items with service lives of 20 years and more it can happen that with time these no longer satisfy changing demands. In certain circumstances modernization of the installation may be required. By the term “modernization” there is to be understood in the following not just exchange of technologically aged components. Modernization can also mean rebuilding or redesigning existing installations and thus adapting these to new needs. Through modernization, elevator installations can, for example, be operated more safely, more efficiently, more comfortably for users and/or more favorably for operators.
In elevator installations of older modes of construction the stories are selected by pressing touch buttons of an input device arranged in an elevator cage. Increasing popularity is enjoyed by elevator installations with story terminals which are arranged on stories and by way of which destination calls can be input from outside the cage, whereby the installations can be operated more efficiently.
SUMMARY
At least some of the disclosed embodiments include a method for modernization of elevator installations. In the modernization a story terminal for input of the destination story is installed on at least one story of the building. This story terminal is so coupled (directly or indirectly) to the control device connected with the input device of the cage side that at least in the standard mode after input of the destination story call detected by means of the story terminal the cage automatically travels to the selected destination story, wherein at the same time a story selection in the cage is no longer possible by use of the input device. With the afore-mentioned indirect coupling it is possible in the modernization to integrate in a control system, which includes the control device, a further control device. Through the addition of the story terminal to the existing installation and the electronic coupling of the story terminal the at least one elevator can be operated by an advantageous destination call control. Due to the fact that in the standard mode after story selection with use of the story terminal is excluded or blocked by way of the input device at least under certain preconditions, unplanned stops of the cage can be prevented and thus the elevator installation operated more efficiently. The input device at the cage side remains in place and can be further used.
The input device having activatable indicating means for representation of selected stories is further adapted in such a manner in the modernization of the control device that the indicating means after input of the story call by way of the story terminal are activated. The mentioned indicating means can in that case be, for example, letters, numbers, drawings or figures illustrated on a touchscreen surface. Activated indicating means can, for example, be lit up more brightly or in another color. The user thus sees in the cage which story he or she has selected beforehand at the story terminal and to which destination the elevator will now convey him or her.
The already existing input device can comprise a touchscreen surface with input buttons possibly of capacitive design, wherein prior to the modernization they react to button contacts and thus enable input of the desired story by the user. In the modernization the control device can be adapted in such a manner that at least in a standard mode the touchscreen function, which reacts to contact, of the input buttons for story selection is deactivated. Apart from the capacitive system, resistive, inductive or other contact-sensitive systems are also conceivable.
In some embodiments the control device can in the modernization be so set by, for example, adaptation of the control program, that the buttons at least associated with the story selection, or the region of the touchscreen surface associated with the story selection, of the input device serves after the modernization substantially only for information purposes.
The input device can have, apart from buttons for story selection, further special input buttons. These special input buttons can be provided for, for example, issue of an alarm in emergency situations, emergency opening or possibly for ensuring a longer time of opening for disembarking of handicapped users. The system containing the story terminal, the input device and the control device can be adapted in such a manner in the modernization that after the modernization the mentioned special input buttons are operable in an operating mode in which the special input buttons—by contrast to the input buttons for the story selection—remain activatable.
If the input device comprises a card reader and/or a handicapped person's button it can be advantageous if in the modernization the control device is adapted in such a manner that after reading of an authorized card or in the case of button pressure on or button contact with the handicapped person's button the deactivated input buttons are freed for renewed input for an activation. In this manner an efficient and nevertheless flexible mode of operation for the elevator can be ensured after the modernization.
Further embodiments comprise the use of an input device of the cage side, which possibly comprises a touchscreen surface with input buttons, possibly of capacitive design, wherein the input device is distinguished by the fact that it can be used unchanged in an elevator installation before and after modernization. Before modernization, the user has to input the desired story by way of input buttons rather than input means. After the modernization the input device serves with respect to the input means concerning stories only for information purposes. After the story selection, i.e. after input of the destination story call detected by means of the story terminal, a story selection in the cage is no longer possible by users of the input device.
Further embodiments relate to a computer program product for operating and modernization of the afore-described installation.
BRIEF DESCRIPTION OF THE DRAWINGS
Further individual features of the disclosed embodiments are evident from the following description of an exemplifying embodiment and from the drawings, in which:
FIG. 1 shows a simplified illustration of an existing installation or an installation to be modernized;
FIG. 2 shows the elevator installation after modernization; and
FIG. 3 shows a further variant of the elevator installation after the modernization.
DETAILED DESCRIPTION
FIG. 1 shows an elevator installation, which is denoted overall by 1 , with an elevator 2 , which has a cage movable in a vertical shaft. Depending on the size of the building and the building purpose the elevator installation can also comprise several elevators arranged adjacent to one another, which can be designed to be the same as or similar to that in FIG. 1 . Also not illustrated are the further stories disposed above and below with respect to the story plane F.
A cage 3 of the elevator installation is, for example, fastened to several support cables 13 and movable upwardly and downwardly by way of known drive means. The following modernization method still to be described in more detail is, however, also suitable for other elevator types. In particular, instead of support cables also other support means such as individual or multiple support belts of different materials and compositions such as synthetic materials, metals or other materials can come into question. The modernization method would also be conceivable for hydraulically operated elevators.
A line by way of which the drive means (not illustrated) are activatable is indicated by 10 . The elevator installation according to FIG. 1 contains on each story of the building an input device 7 which is mounted on a vertical wall and disposed near the elevator shaft and by way of which a user can call the cage to his or her story. Input devices of that kind at the story side are also located in the stories lying above and below. An input device, which is denoted by 4 , is arranged at an inner side of a cage wall of the elevator cage 3 . The input device 4 has input buttons 5 by way of which the user can input his or her destination story. Apart from these destination story input buttons 5 the input device 4 has further buttons 11 for special purposes. These buttons 11 serve for, for example, issue of an alarm, emergency opening or as a so-called handicapped person's button. The story terminal 8 has, for example, a touchscreen surface on which the input buttons 9 and 11 are arranged.
The control device denoted by 6 is electronically connected by way of conductors, which are indicated by lines, with the input device 4 at the cage side, the cage call input device 2 and by way of the conductor 10 with the drive for the elevator 2 . The device at the cage side comprises a touchscreen surface, the input buttons 5 and 11 of which are designed as capacitive touch-sensitive buttons. The input device 4 is designed in such a manner that, for example, at the time of or after selection of a story the corresponding button after contact by the user lights up. The control device 6 comprises memory means (not illustrated) on which data and a computer program for operating the elevator installation 1 are stored. The control device 6 has an interface 16 by way of which communication with the control system can be produced and further data can be supplied to the memory means of the control device 6 .
The demands imposed on an elevator installation can change in the course of time. Starting from the existing installation according to FIG. 1 the elevator installation can be modified in such a manner by the disclosed modernization methods that the elevator installation can thereafter be operated more efficiently. In the modernization, story terminals are installed on the stories of the building, which terminals are connected with the control device 6 by way of data lines 18 ( FIG. 2 ). The story terminals 8 can, as evident from the exemplifying embodiment according to FIG. 2 , be designed as column-like column bodies protruding relative to the floor of the story plane F. The story terminal 8 has, by way of example, an inclined surface on which input buttons 9 for each story are arranged. Indicating means 14 for allocation of the elevator to the user are arranged on a horizontal surface. Other shapes and modes of construction for story terminals are obviously also conceivable. As evident from FIG. 2 , in the course of the modernization the input devices located on the stories near the shaft are removed (see FIG. 1 : input device 7 ). However, further embodiments can leave the installed input device ( 7 ; FIG. 1 ) in place and merely deactivate the corresponding buttons of the mentioned input device by adaptation of control system. Alternative story terminals could comprise touchscreens fastened to building inner walls. For example, at each story a flat story terminal could replace the simple cage call input device or be arranged in place thereof on the wall.
In the modernization, a technician produces a connection with the control system by way of the interface 16 and in that case introduces a new computer program product or an update for the existing computer program product into the system, whereby after the modernization the elevator installation can be operated in the previously described mode and manner. The computer program product or the update thereof is stored in an electronic data processing unit. This data processing unit can be a component of the control device 6 . However, it would also be conceivable to arrange the data processing unit at the input device 4 at the cage side.
A technician can now perform the upgrade of the elevator installation and reconfigure the control in simple mode and manner by a laptop 17 or another apparatus. A corresponding data packet for the update or the reconfiguration of the control can be filed on a memory element (for example a memory card). Moreover, it would also be conceivable to design, by means of portable wireless transmitters or by way of a near-field radio connection, for prevention of improper interventions in the control system. The coupling can be effected by way of data cable or also in wire-free manner. The interface can then also be designed in such a manner that a technician can access and intervene on or in the control system from a remote location in that he or she, for example, executes a so-called ‘remote’ by way of the Ethernet. In this manner, the modernization can be performed very rapidly. Through the reuse of the existing touchscreen of the input device 4 it can be ensured that—with the exception of the story terminal to be installed—no high investment costs in the elevator installation are needed.
After modernization has been carried out, the mode of operation of the elevator installation 1 in the standard mode is as follows: After the user has selected the destination story, which is designed by him or her, on the story terminal 8 with use of the buttons 9 an elevator is allocated to him or her by the display 14 ( FIG. 2 ). In the cage 3 of the elevator 2 allocated to him or her the touchscreen surface of the input device 4 shows the story previously selected by him or her. This can be effected, for example, by lighting up the input button provided with a number for a story. An input button lit up in that manner is indicated in FIG. 2 by 5 ′. A card reader 12 is disposed below the touchscreen surface of the input device 4 . The card reader can also be integrated in the input device 4 .
Other locations for the card reader are also conceivable. Thus, the card reader could comprise, for example, a sensor or a receiver arranged behind the same glass pane for the touchscreen surface of the input device 4 . The story terminals do not necessarily have to comprise touchscreen surfaces; tactile pushbuttons or other input variants, for example, also come into question. The story selection can additionally or alternatively be effected for input via the buttons 9 also through an identification of the user. For this purpose the story terminal 8 can comprise a card reader 15 or other identification unit. After identification of an authorized user, for example by means of an ID card, the control system recognizes to which destination story the user would like to travel.
In at least some embodiments, the region, which is associated with the story selection, of the touchscreen surface of the input device with the input buttons 5 serves, after the modernization, only for information purposes. The input device 4 receives, triggered by the story selection at the story terminal 8 , an activation signal from the control device. Thereafter, the indicating means associated with the selected story are activated for representation of the story. Indicating means activated in that manner can comprise lighting up. Insofar as the remaining indicating means at least in the operating phase permanently light up, it can be advantageous if the activated indicating means lights up more brightly and/or in another color. The indicating means can be designed as components separate from the input buttons. The indicating means can be designed as an integrated component of the input buttons. A button indicating a story in this manner by lighting up is indicated in FIG. 2 by way of example as a button denoted by 5 ′. In addition, after the modernization, usual specific input buttons can remain activatable. The buttons serving for special purposes such as issue of an alarm, emergency opening or the like are denoted in FIGS. 1 and 2 by 11 .
The modernized control system, however, also permits departures from the standard mode for specific cases: Thus, the control system can optionally be adapted in such a manner that after reading of an authorized card and/or in the case of button pressure on or button contact with a handicapped person's button 11 the deactivated input buttons 5 are freed for renewed input for activation.
Depending on how the hardware of the original control device was designed, it can be necessary in the modernization to undertake control engineering adaptations of the control system so as to enable the new functionality. In cases of that kind, as evident from FIG. 3 , an additional control device 19 or a further control module is integrated in the control system. As far as the newly added control device 19 , the elevator installation 1 corresponds with the installation of FIG. 2 . In FIG. 3 the control device 19 is, by way of example, constructed as a separate subassembly disposed in operative connection with the first control device 6 . The control device 19 can already be pre-configured, whereby the elevator installation is quickly ready for reuse. Moreover, it is also conceivable to configure the control or if required also undertake an update or a reconfiguration of the control software by way of means (not illustrated here) such as, for example, a laptop connected by way of an appropriate interface, by way of a near-field radio connection or by way of an Ethernet remote.
Having illustrated and described the principles of the disclosed technologies, it will be apparent to those skilled in the art that the disclosed embodiments can be modified in arrangement and detail without departing from such principles. In view of the many possible embodiments to which the principles of the disclosed technologies can be applied, it should be recognized that the illustrated embodiments are only examples of the technologies and should not be taken as limiting the scope of the invention. Rather, the scope of the invention is defined by the following claims and their equivalents. We therefore claim as our invention all that comes within the scope and spirit of these claims. | A method for modernizing an elevator installation includes installing story terminals for input of a destination story on the stories of the building, which terminals are so coupled with an elevator control device connected with an input device in the elevator cage that, at least in a standard mode, after input of the destination story call detected by means of the story terminal, the cage automatically travels to the selected destination story, and in that case a story selection in the cage by use of the input device is no longer possible. The indicating means for representing selected stories of the input device are so incorporated in the control system that the indicating means, after input of a story call by way of the story terminal, are activated. | 1 |
RELATED APPLICATIONS
[0001] The present application is a continuation application to U.S. patent application Ser. No. 10/807,151, filed Mar. 24, 2004, which claims priority from the Japanese patent applications JP2003-084085 filed on Mar. 26, 2003 and JP2004-015117 filed on Jan. 23, 2004, the contents of those are hereby incorporated by reference into this application.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to a technique for managing progress information and history information, which makes it possible to provide progress information and history information according to a service request.
[0003] In the conventional Web service (an apparatus, a system, or a program, which provides services by use of one Web as an I/F), information is exchanged between systems by use of an interface that has been determined in advance between two specific services. Even when handling notification of progress and history information, a specific interface is defined in advance between the services.
[0004] The technique including Web services is disclosed in “Java WebServices” by David A. Cbappell and others (publishing company: O'Reilly & Associates, Inc., 2002.3, pp. 3-9).
SUMMARY OF THE INVENTION
[0005] Heretofore, if a plurality of Web services are interfaced with one another to realize a series of functions, how to handle progress and history information to be exchanged among the Web services needs to be determined as an interface among specific Web services. Therefore, the following problem arises: in the event of a system in which a plurality of Web services are interfaced with one another, in order to manage progress and history information, a requester of progress and history information is required to issue a request in consideration of interfaces of all related Web services; accordingly, if the number of related Web services increases, processing becomes complicated in response to the number of combinations of the related Web services.
[0006] In addition, if Web services are interfaced with one another in multiple stages, i.e., if a Web service which directly receives a request sends a request to an unspecific Web service, interfaces of all related Web services cannot be taken into consideration, and there is also a case in which a progress request cannot be issued from a Web service other than a direct requester. In this case, progress and history information which can be obtained is limited to information which can be returned by the Web service that directly receives the request.
[0007] In object of the present invention is to provide a service processing method capable of dynamically controlling the obtaining of history information and progress information, and an apparatus thereof.
[0008] According to the present invention, the above-mentioned problems are solved by the following steps: without individually determining an interface of progress and history information among specific systems, prescribing an information format used to exchange progress and history information among a plurality of systems; then issuing a request for progress and history information together with an individual API request; and when a state changes in each Web service, transmitting required information in the common format.
BRIEF DESCRIPTION OF THE DRAWING
[0009] FIG. 1A is a diagram illustrating an example of a service request adopted when an online order system is built by combining a plurality of Web services together;
[0010] FIG. 1B is a diagram illustrating an example of service progress notification adopted when an online order system is built by combining a plurality of Web services together;
[0011] FIG. 2 is a diagram detailing a configuration of request data transmitted from each Web service;
[0012] FIG. 3 is a diagram illustrating how systems of an A Company, a B Company, and a C Company are configured;
[0013] FIG. 4 is a diagram detailing order specification data transmitted from an A Company Web service to a B Company Web service;
[0014] FIG. 5 is a diagram detailing data of an order of basic configuration equipment, which is transmitted from the B Company Web service to a C Company Web service;
[0015] FIG. 6 is a diagram detailing data of an order of basic configuration equipment, which is transmitted from the B Company Web service to the C Company Web service;
[0016] FIG. 7 is a diagram illustrating a process flow of the B Company Web service;
[0017] FIG. 8 is a diagram detailing contents of progress information notification data of the B Company Web service;
[0018] FIG. 9 is a diagram illustrating how a format of progress information request data is defined;
[0019] FIG. 10 is a diagram illustrating how a format of progress information notification data is defined;
[0020] FIG. 11 is a table for managing progress information request data that is transmitted to the B Company Web service;
[0021] FIG. 12 is a table used for managing progress notification information of the B Company Web service; and
[0022] FIG. 13 is a table used for managing progress notification information of the A Company Web service.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0023] FIGS. 1A and 1B are diagrams each illustrating an example in which a plurality of Web services are combined to build an online order system.
[0024] Reference numeral 101 in FIG. 1A denotes an A Company Web service used for an order system which places an order of custom-ordered system equipment from an A Company. Reference numeral 102 in FIG. 1A denotes a B Company Web service. With respect to the custom ordered system, the order of which is received from the A Company, the B Company Web service transmits an order of the basic configuration equipment to a C Company Web service 103 shown in FIG. 1A , and also transmits an order of an optional device to a D Company Web service 104 shown in FIG. 1A .
[0025] Moreover, the Company D Web service 104 transmits an order of a component of the optional device to an E Company Web service 105 shown in FIG. 1A , and transmits an order of another component of the optional device to a F Company Web service 106 shown in FIG. 1A .
[0026] Reference numeral 107 in FIG. 1A denotes transmit data of the order of the custom-ordered system equipment, which is transmitted from the A Company Web service 101 to the B Company Web service 102 . Reference numeral 108 in FIG. 1A denotes transmit data of the order of the basic configuration equipment, which is transmitted from the B Company Web service to the C Company Web service. Reference numeral 109 in FIG. 1A denotes transmit data of the order of the optional device, which is transmitted from the B Company Web service to the D Company Web service. Reference numeral 110 in FIG. 1A denotes transmit data of the order of the optional device, which is transmitted from the D Company Web service to the E Company Web service. Reference numeral 111 in FIG. 1A denotes transmit data of the order of the optional device, which is transmitted from the D Company Web service to the F Company Web service.
[0027] As for a request for the order of the custom-ordered system equipment 107 coming from the A Company Web service, a message 801 in FIG. 1B includes progress information notification data of the B Company Web service which is transmitted from the B Company Web service to the A Company Web service.
[0028] Messages 901 and 902 are progress information notification data of the C Company Web service. When a state of the C Company Web service changes, the messages 901 and 902 are transmitted as data having a format similar to that of the progress information notification data 901 of the B Company Web service.
[0029] The progress information notification data 901 of the C Company Web service is progress information notification data corresponding to progress information request data (for the A Company Web service) 502 transmitted through the B Company Web service. The progress information notification data 902 of the C Company Web service is progress information notification data corresponding to progress information request data (for the B Company Web service) 503 .
[0030] In a similar manner, messages 903 and 904 are progress information notification data of the D Company Web service. When a state of the D Company Web service changes, the messages 903 and 904 are transmitted as data having a format similar to that of the progress information notification data 801 of the B Company Web service.
[0031] The progress information notification data 903 of the D Company Web service is progress information notification data corresponding to progress information request data (for the A Company Web service) 502 transmitted through the B Company Web service. The progress information notification data 904 of the D Company Web service is progress data corresponding to progress information request data (for the B Company Web service) 503 .
[0032] FIG. 2 is a diagram illustrating a part of the processing shown in FIGS. 1A and 1B , in which the C Company Web service 103 and the D Company Web service 104 are called from the A Company Web service 101 through the B Company Web service 102 . In addition to it, FIG. 2 illustrates details of the request data.
[0033] The order of custom-ordered system equipment 107 is order data transmitted from the A Company Web service 101 to the B Company Web service. The order of custom-ordered system equipment 107 includes order specification data of the custom-ordered system equipment shown in a message 401 in FIG. 4 , and progress information request data 402 used in a Web service history and progress management method. In this embodiment, information included in both of the messages 401 and 402 is described on the basis of the XML format as an example. The present invention is not limited to the XML.
[0034] In a similar manner, the order of basic configuration equipment 108 shown in FIG. 2 is order data from the B Company Web service to the C Company Web service. The order of basic configuration equipment 108 includes order specification data 501 of the basic configuration equipment in FIG. 5 , progress information request data (for the A Company Web service) 502 , and progress information request data (for the B Company Web service) 503 . The order of optional device 109 shown in FIG. 2 is order data from the B Company Web service to the D Company Web service. The order of optional device 109 includes order specification data 601 of the optional device in FIG. 6 , progress information request data (for the A Company Web service) 502 , and progress information request data (for the B Company Web service) 503 .
[0035] FIG. 3 is a diagram illustrating how systems of an A Company, a B Company, and a C Company, which are shown in FIG. 1 , are configured.
[0036] To be more specific, FIG. 3 illustrates in detail how the A Company Web service 101 , the B Company Web service 102 , and the C Company Web service 103 are configured. The A Company Web service 101 has an order specification input unit 201 for inputting specifications of the custom-ordered system, an order and request transmission unit 202 , and an order information storing area 203 for storing transmitted order data. In addition, the A Company Web service 101 also has a progress and history notification receiving unit 204 for receiving progress and history information from the other systems, a progress and history information storing area 205 for storing the information, and a progress and history display unit 206 for displaying a stored history.
[0037] The B Company Web service 102 has the following: an order and request receiving unit 207 for receiving order data transmitted from the A Company, and the like; a component order transmission unit 208 for transmitting an order request for a component to the C Company Web service and the D Company Web service; and an order information storing area 209 for storing order data. In addition, the B Company Web service 102 has a progress and history notification receiving unit 210 for receiving progress and history information; a progress and history notification storing area 211 for storing the received progress and history information; a progress and history notification transmission unit 212 for transmitting progress and history information; and a progress and history display unit 213 for displaying progress and history information.
[0038] The C Company Web service 103 has an order and request receiving unit 214 for receiving order data transmitted from the B Company, and the like, and an order information storing area 215 for storing order data. In addition, the C Company Web service 103 has the following: a progress and history information transmission unit 216 for transmitting progress and history information; a progress and history information storing area 217 for storing the progress and history information; and a progress and history display unit 218 for displaying progress and history information. These Web services 101 through 103 are realized by use of information processing devices. The processing units 201 through 206 , 207 , 208 , 210 through 213 , 214 , 216 , 218 are functions achieved by the execution of programs. The information 203 , 205 , 209 , 211 , 215 , 217 are stored in storage devices including a memory and a magnetic disk.
[0039] The order specification data 401 shown in FIG. 4 is order specification data used to specify the order for the custom-ordered system equipment, which is transmitted from the A Company Web service to the B Company Web service. The order specification data 401 is specified when using each function of the Web services. Contents of the order specification data 401 correspond to contents of each Web service. The order specification data of the custom-ordered system equipment includes a system type, the number of orders, the delivery date, an additional optional device, and another additional optional device which are specified to be “general-purpose system 2 type”, “3”, “May 21, 2002”, “memory expansion”, and “NIC expansion” respectively. This data is required for each service to perform services. A format for specifying the data is determined on the basis of contents of each service. The order specification data 401 shown in FIG. 4 is one example of how the format is determined.
[0040] The progress information request data 402 is information that is used to pass history request information many times among the plurality of Web services, and thereby to manage history and progress information of the plurality of systems. Reference numeral 1001 in FIG. 9 shows definitions of a format of the progress information request data 402 . Information 403 through 407 in FIG. 4 corresponds to progress information request data, a destination of progress information notification, a requester ID, a degree of details of return information, a hierarchical level respectively, all of which are defined in the definition of progress information request data 1001 . Each of the above-mentioned items will be described in detail by use of an example as below.
[0041] The progress information request data 402 shows details of the progress information request data. With the object of indicating that the progress information request data 402 is an information group used to notify the A Company Web service of progress information, information 403 specifies “progress information request”. The information 403 defines a progress information request that includes information 404 through 407 used to notify the progress information.
[0042] Information 404 is a destination of progress information notification. Information indicating a destination which is notified of progress information is set. In this embodiment, information used to receive progress information of the A Company Web service is set by use of an URL.
[0043] In this embodiment, the A Company Web service sets the data as the progress information request in the progress information request data 402 . However, the following method can also be used: apart from the A Company Web service, providing another Web service that manages progress information and history information; and as a destination of progress information notification of the information 404 , instead of specifying information used to receive progress information of the A Company Web service, specifying a progress-information use URL of the Web service for managing progress information and history information, which has been provided apart from the A Company Web service.
[0044] Information 405 is a requester ID. What is specified is data obtained by numbering a requester with the object of managing order data of the A Company Web service. If this requester ID is specified in the progress information notification data when transmitting the progress information notification data from the B Company Web service to the A Company Web service, the A Company Web service can identify an order corresponding to this progress information notification. In this embodiment, “000A012” is specified as the requester ID. However, if a requester ID can be used to identify order data which is a request from the A Company Web service and to identify progress information notification data which is transmitted from each of the other Web services in association with the order data, other formats may also be used as a character string and a numerical value.
[0045] Information 406 is data indicating a degree of details of return information. This is information that indicates a unit of transmission of progress information management, of which the A Company is notified. In this embodiment, “maximum” is specified. This indicates that as progress information of business logic in the B Company Web service that has received this new request data, progress information is returned in the maximum resolvable unit. When the degree of details of return information is “maximum”, progress information is requested as detailed as possible; for example, if a business process of each service includes a plurality of operation steps, progress information of each operation step is requested.
[0046] For example, the business process includes operation steps of “receive processing”, “inspection”, “confirmation of delivery date”, and “ordering”, progress information is notified on an operation step basis. As the degree of details of return information, “debug”, “maximum”, “input/output”, “minimum”, “error”, and the like, including the above-mentioned example, can also be specified as a unit of progress information to be notified. In this example, in the event of the “debug”, the amount of progress information notification data is largest; and in the event of the “error”, the amount of progress information notification data is smallest.
[0047] The degree of details of return information is a value indicating a unit expected by the A Company Web service that requests the progress information notification data. On the basis of the degree of details of return information, each service returns the progress information notification data in a unit that can be achieved by the service at the time of returning the progress information notification data. The “debug” is specified with the object of notifying further detailed progress information at a stage of handling each operation step to be notified in the event of “maximum”. The “debug” is used for a test, or the like. In this case, detailed progress information required for the test is defined beforehand. The “input/output” indicates that progress notification information about input/output from/to a service other than this service is required; for example, a case where a request is received from another service, a case where a request is further issued to another service, or the like. Moreover, the “minimum” indicates that progress notification information is required at a minimum level which is considered by each service as a required minimum level. The “error” indicates that progress notification information is requested only when a problem which does not occur in usual operation occurs.
[0048] The degree of details of return information indicates a target unit of progress information. However, it is also possible to specify a classification, and a filter condition, of requested progress information so that only progress information relating to a specific classification is obtained; for example, only “start” and “completed” for a processing step such as a request to another Web system are obtained.
[0049] The hierarchical level, which is the information 407 in FIG. 4 , is used to specify a notification range of progress information if a series of processing involves a plurality of Web services. The hierarchical level is specified as a numerical value equivalent to the number of stages that is counted from a first Web service. For example, when counting from a Web service that requests a service, a first destination Web service is a first stage. If the first destination Web service calls another Web service, said another Web service is a second stage. In other words, if progress up to two stages from the A Company Web service needs to be kept track of, for example, a hierarchical level of “2” is transmitted to the B Company Web service. The B Company Web service transmits a hierarchical level of “1” to the C Company Web service. Because the C Company Web service receives “1” as the hierarchical level, the C Company Web service judges that it is not necessary to transmit a progress information request to a Web service, a level of which is lower than the C Company Web service.
[0050] In the example of the information 407 shown in FIG. 4 , “2” is specified. This shows that a range within which the A Company Web service is notified of progress information is two stages. With reference to FIG. 2 , the B Company Web service 102 , which is the first stage, and the C Company Web service 103 and the D Company Web service 104 , which are the second stage, are requested to transmit progress information to the A Company Web service.
[0051] By setting the progress information request data 402 shown in FIG. 4 , and then by issuing a request from the A Company Web service to the B Company Web service together with the order specification data 401 , it is possible to notify progress information by use of data format, which is common to a plurality of Web services, without individually creating an interface of progress information among individual Web services to create processing that is specific to the individual Web services.
[0052] FIG. 5 illustrates contents of data to be transmitted as the order of basic configuration equipment 108 from the B Company Web service to the C Company Web service. The data includes the following: order specification data 501 of the basic configuration equipment, which shows contents of the order for basic configuration equipment; progress information request data (for the A Company Web service) used to request notification of progress information to the A Company Web service 502 ; and progress information request data (for the B Company Web service) 503 used to request notification of progress information to the B Company Web service.
[0053] The order specification data 501 in FIG. 5 is data relating to the order for basic configuration equipment. In this embodiment, a system type, the number of orders, the delivery date are specified to be “general-purpose system 2 type”, “3”, “Apr. 4, 2002” respectively. The system type and the number of orders have the same values as those in the order specification data 401 of the custom-ordered system equipment in FIG. 4 . As for the delivery date, after the basic configuration equipment and the optional device are delivered, on the basis of the values of the order specification data 401 of the custom-ordered system equipment in FIG. 4 , a value obtained by subtracting a period of time required for assembling is specified.
[0054] The progress information request data (for the A Company Web service) 502 shown in FIG. 5 is information used to return progress information to the A Company Web service. The progress information request data 502 is generated on the basis of the progress information request data 402 from the A Company Web service. Information ranging from a destination of progress information notification 404 to a degree of details of return information 406 is similar to progress request data 402 from the A Company Web service in FIG. 4 . Because the progress information request data 502 is passed through the B Company Web service, “1” is specified as the hierarchical level 505 as a result of decrementing its value by one.
[0055] The progress information request data (for the B Company Web service) 503 shown in FIG. 5 is transmit data used to request transmission of progress information to the B Company Web service. The progress information request data 503 has a format similar to those of the progress information request data 402 and the progress information request data 502 . Information 507 shown in FIG. 5 is a destination of progress information notification, which specifies an URL indicating a destination of progress and history notification information of the B Company Web service. Information 508 is an ID for identifying a specific order, which is set by the B Company Web service. In this embodiment, a degree of details of return information 509 is specified to be “maximum”; and a hierarchical level 510 is specified to be “2”.
[0056] FIG. 6 illustrates contents of data to be transmitted as the order of the optional device 109 from the B Company Web service to the D Company Web service. The data includes the following: order specification data 601 of the optional device, which shows contents of the order for the optional device; progress information request data (for the A Company Web service) used to request notification of progress information to the A Company Web service 502 ; and progress information request data (for the B Company Web service) 503 used to request notification of progress information to the B Company Web service.
[0057] The order specification data 601 of the optional device shows contents of an order for the optional devices that are included in the order specification data 401 of the custom-ordered system equipment in FIG. 4 . This order for the optional devices needs to be placed with the C Company Web service. Device types of the order specification data 601 are determined on the basis of the additional optional devices in the order specification data 401 of the custom-ordered system equipment. In this example, “memory” and “NIC” are specified. In addition, the number of orders is specified to be “3”, which is the same as that of the order specification data 401 of the custom-ordered system equipment. As for the delivery date, after the basic configuration equipment and the optional device are delivered, on the basis of the values of the order specification data 401 of the custom-ordered system equipment in FIG. 4 , a value obtained by subtracting a period of time required for assembling is specified.
[0058] In this embodiment, contents of the progress information request data (for the A Company Web service) 502 and the progress information request data (for the B Company Web service) 503 , which are shown in FIG. 6 , are the same as those of the progress information request data 502 and 503 included in the data of the order for the basic configuration equipment which is transmitted from the B Company Web service to the C Company Web service.
[0059] In the order specification data 601 of the optional device, a device type, the number of orders, and the delivery date are specified twice as the order specification data of the optional device.
[0060] FIG. 8 is a diagram illustrating contents of the progress information notification data 801 of the B Company Web service, which is transmitted to the A Company Web service when a state of the B Company Web service changes. Reference numeral 1002 of FIG. 10 denotes definitions in the format of the progress information notification data 801 of the B Company Web service. Reference numerals 803 through 811 shown in FIG. 8 , which are defined in the definitions of progress information notification data 1002 , denote respectively the following items: a requester of status check, a target service, a requester ID, progress information notification including a current status, a service ID that is a detailed item of the current status, a service name, the date and time, target processing, and a state. Each of the above-mentioned items will be described in detail by use of examples as below.
[0061] Reference numeral 802 in FIG. 8 denotes progress information notification, which includes information from the requester of status check 803 to the current status 806 .
[0062] The requester of status check 803 indicates a requester that has requested the progress information. The contents of the requester of status check 803 become the same as those of the destination of progress information notification 404 in the progress information request data 402 .
[0063] The target service 804 indicates a target of the progress information which is specified by the progress information notification data 801 . In this case, an URL indicating the B Company Web service is specified.
[0064] Reference numeral 805 denotes a requester ID. Contents specified as the requester ID 805 are the same as those of the requester ID 405 in the progress information request data 402 . This information enables a requester of progress information to identify an order corresponding to the progress information.
[0065] The current status 806 shows a status after a change instate in the B Company Web service. The current status 806 includes information from the service ID 807 to the state 811 .
[0066] The service ID 807 is an ID used to identify a target in the B Company Web service. When a request for the newest progress state is transmitted from the A Company Web service to the B Company Web service in arbitrary timing except at the time of receiving, or when history information is requested, the progress information notification data 801 can be used to specify a target.
[0067] The service name 808 is a service name of the B Company Web service. When progress information collected from a plurality of Web services is displayed in the A Company Web service, using this name makes it possible to indicate how the Web services correspond to the progress information.
[0068] The date and time 809 indicates the date and time when a state has changed.
[0069] If a business process in the B Company Web service includes a plurality of operation steps, the target processing 810 indicates a name of an operation step, a state of which has changed.
[0070] The state 811 indicates a current state of the target processing 810 after the state has changed. The state 811 is provided with one of values each indicating a state. The values include “completed”, “being executed”, “being stopped”, “waiting for receiving”, “not executed”, “forcedly stopped”, “external request is stopped”, “abnormally ended”, “execution is omitted”, or the like.
[0071] The progress information service 812 indicates a Web service to which an inquiry is sent. The progress information service 812 is used, for example, when it is necessary to send an inquiry about the newest progress information to the B Company Web service.
[0072] FIG. 11 illustrates a table for managing progress information request data that is transmitted to the B Company Web service.
[0073] A destination of progress information notification 1101 , a requester ID 1102 , a degree of details of return information 1103 , and a hierarchical level 1104 are items that correspond to the items 404 , 405 , 406 , 407 of the progress information request data 402 of the A Company Web service. The service ID 1105 is data that is obtained as a result of unique numbering in a service. When a state of a transaction is changed, the service ID 1105 is used to identify a destination of progress information notification.
[0074] FIG. 12 illustrates a table for managing progress notification information of the B Company Web service. The service ID 1201 has the same value as that of the service ID 1105 . The service ID 1201 is data that is obtained as a result of unique numbering in a service. A transaction name 1202 , target processing 1203 , a person in charge 1204 are information used for management in the B Company Web service. A progress information service 1205 , a target service ID 1206 , a target service name 1207 , the target update time 1208 , target processing 1209 , and a target state 1210 are areas for storing progress information notified by the other Web services.
[0075] FIG. 13 illustrates a table for managing progress notification information of the A Company Web service. Contents of items 1301 through 1310 are similar to those of the items 1201 through 1210 in the progress notification information of the A Company Web service.
[0076] FIG. 7 is a flowchart illustrating a series of processing from the time when the B Company Web service has received an order of the custom-ordered system equipment 107 from the A Company Web service 101 until the B Company Web service returns progress data to the A Company Web service.
[0077] As soon as the B Company Web service receives an order of custom-ordered system equipment 107 by use of the order and request receiving unit 207 (step 701 ), the B Company Web service checks contents of order data, and then creates, as component order data, the order specification data 501 of the basic configuration equipment, which is transmitted to the C Company Web service, and the order specification data 601 of an optional device, which is transmitted to the D Company Web service (step 702 ).
[0078] Next, a unique ID is created as an ID corresponding to the order of the custom-ordered system equipment 107 . Then, the order data is stored in the order information storing area 209 shown in FIG. 3 (step 703 ). In addition, contents of the progress information request data 402 are stored in a progress information request management table 1100 (for the B Company Web service) in the progress and history information storing area 211 shown in FIG. 3 (step 704 ).
[0079] In the progress information request data 402 requesting progress information to be transmitted to the A Company Web service, the hierarchical level indicates two stages. Therefore, the progress information request data 502 is created. In this case, the progress information request data 502 shows a request for progress information to be transmitted to the A Company Web service from the C Company Web service and the D Company Web service, with which the B Company Web service has placed the orders for components. At this time, the hierarchical level 505 is specified to be “1” as a result of decrementing by one. At the same time, the progress information request data 503 which requests progress information to be transmitted to the B Company Web service is created. For the purpose of managing the association of the progress information notification data from the C Company Web service with that from the D Company Web service, the progress information request management table 1100 of the B Company Web service stores information including the service ID 1201 , the transaction name 1202 of a transaction managed in the B Company system, the target processing 1203 , and the person in charge 1204 (step 705 ). The service ID 1201 is the ID created in the step 703 .
[0080] The order data created in the step 702 combined with the progress information request data created in the step 705 is transmitted to the C Company Web service 103 as data of the order of the basic configuration equipment 108 to be transmitted to the C Company Web service, and to the D Company Web service 104 as data of the order of optional device 109 to be transmitted to the D Company Web service (step 706 ).
[0081] On the completion of the step 706 , a state of component order transmission processing of the B Company Web service is changed to “completed”. Because the state is changed, the B Company Web service searches for a destination of progress information notification using as a key the service ID 1105 of the progress information request management table of the B Company Web service. After that, on the basis of the progress information request data 402 from the A Company Web service, the B Company Web service creates the progress information notification data 801 shown in FIG. 8 , which indicates a progress state in the B Company Web service (step 707 ), and then transmits the progress information notification data 801 to the A Company Web service (step 708 ).
[0082] In addition, as for the C Company Web service, when a state is changed (for example, when the basic configuration equipment which is the ordered product is dispatched), on the basis of the progress information request data 502 from the B Company Web service, by means of processing similar to the processing steps 707 and 708 in the B Company Web service, the C Company Web service creates the progress information notification data 901 of the C Company Web service, and then transmits the progress information notification data 901 to the B Company Web service (step 709 ).
[0083] The B Company Web service, which has received the progress information notification data 902 of the C Company Web service, stores information of the progress information notification data 902 of the C Company Web service in the progress notification information management table 1200 of the B Company Web service. At the same time, the B Company Web service searches the progress information request management table 1100 of the B Company Web service for the service ID 1105 , and thereby identifies a destination of progress information notification. Then, as is the case with the step 707 , the B Company Web service creates the progress information notification data shown in FIG. 8 , which shows a change in progress status in the B Company Web service (step 717 ). In the progress information notification data which is created in the step 717 , the date and time 809 , the target processing 810 , and the state 811 , of the progress information notification data 801 , which has been transmitted from the B Company Web service to the A Company Web service in advance, are changed according to the progress information notification data 902 of the C Company Web service. Their values, therefore, are replaced with “Aug. 8, 2002 8:00:00”, “receipt of delivery notification of basic configuration equipment”, and “completed” respectively.
[0084] The progress information notification data of the B Company Web service, which has been created in the step 717 , is transmitted to a destination indicated by the destination of progress information notification 1101 in the progress information request management table 1100 of the B Company Web service (step 718 ).
[0085] In the A Company Web service, the progress information notification data which is notified in the steps 708 and 709 , and the progress information notification data which is notified from the C Company Web service, are stored in a progress notification information management table 1300 of the A Company Web service shown in FIG. 13 .
[0086] When a person in charge of the A Company checks progress, contents of the progress notification information management table 1300 of the A Company Web service are referred to.
[0087] As described above, by setting progress information request data in the format as shown in the progress information request data 402 in FIG. 4 , and then by transmitting the set progress information request data together with information used to realize functions of a Web service, it is possible to notify progress information by use of a data format, which is common to a plurality of Web services, without individually creating an interface of progress information among individual Web services to create processing that is specific to the individual Web services. Transmitting a progress information request together with a service request for realizing the functions of a Web service makes it possible to individually choose an interface of progress information among Web services.
[0088] According to the present invention, it becomes possible to dynamically control the obtaining of history information and progress information. | The present invention provides service processing used in a computer system comprising a plurality of computers, each of which receives a message and executes a Web service on the basis of the message and then outputs a message generated from the result of the execution. The computer system realizes a Web service by transmitting and receiving the message among the computers. A message including first information about the execution of the service, and second information about notification of progress information in the service, is received. The service is executed according to the first information, and then the second information is analyzed. After that, on the basis of the execution result of the service, a message is generated according to the second information, and the message is then transmitted to the computer that is identified by a destination of progress information notification included in the second information. | 6 |
FIELD OF THE INVENTION
[0001] The invention relates to a yarn braking device.
BACKGROUND OF THE INVENTION
[0002] In a known yarn braking device (EP 0 534 263 A) a mechanical spring constitutes both the axial force generator and the radial centering device. The spring may be an annular radially oriented diaphragm, a radial spiral spring, a conical spiral spring, a cylindrical bellows, or, as shown in FIG. 1 of EP 0 652 312 A, a star-shaped spring arrangement consisting of helical tension springs each of which is hooked into the holder and into the support ring body, respectively. A general problem of mechanical springs is a development of the force which is not uniform in circumferential direction, the susceptibility to aggressive substances, and a tendency to collect lint. A further problem is that the mechanical spring at the same time has to centre in radial direction and has to transmit the axial force on the braking body. This dual function means a compromise between the development of the resilient axial force and of the radial centering force and might be critical in cases of extreme braking effects, i.e. if the same reliable centering of the frustocone coat braking body is necessary in case of an extremely weak braking effect or in case of an extremely strong braking effect. The adjustment range of the braking effect is limited by the nature of the mechanical spring, meaning that the mechanical spring has to be substituted by another as soon as a significant variation of the braking effect is needed. Basically, the braking effect is adjusted by the axial position of the holder in relation to the withdrawal end in order to load the spring more or less. In the case of a very weak braking effect due to the low spring load the centering and automatic return of the dislocated braking body into the centered position may fail, while in the case of an extremely strong adjustment of the braking effect the centering may be too rigid due to the high spring load. An optimal and constant centering effect and the capability of the braking body to automatically return after occurrence of a needed lateral displacement into a perfectly centered position on the withdrawal end of the braking body is, however, a decisive prerequisite for a correct braking function, since the large diameter end region of the frustocone coat braking body only then is able to produce a uniform braking effect along the circumference of the withdrawal end when the small diameter end of the frustocone coat braking body remains perfectly centered. Already small misalignments results in permanent fluctuations of the braking effect and in undesirable variations of the yarn tension. The yarn which rotates during withdrawal from the storage body in the yarn braking device like the hand of a clock in most cases is deflected in the support ring body and then applies a rotating, outwardly directed force on the braking body which force is varying, e.g. in case of a passing knot, and which has to be taken up and compensated permanently by the centering device. For that reason a properly operating centering device has a significant functional importance for this kind of a yarn braking device.
[0003] It is known from DE 195 31 579 A in a small diameter circular disc brake, which the yarn is only passing laterally, to press the braking discs against each other by axially repelling permanent magnet rings. However, due to the only linearly passing yarn the functional requirements for centering are low since the discs are centered mechanically and are inclined in relation to each other during operation.
[0004] Furthermore, it is known for controlled yarn braking devices (DE 198 39 272 A, EP 0 652 312 A, U.S. Pat. No. 5,778,943 A), the braking effect of which either can be modulated or can be switched off completely, to provide a magnetic axial force generator for a basic braking effect or passive position in combination with a mechanical spring arrangement. The axial force generator comprises at least one coil which is supplied with current. In the deenergised condition the axial force generator does not generate any force.
[0005] It is an object of the invention to provide a non-controlled yarn braking device of the kind mentioned in the beginning which is structurally simple and reliable, allows a broad adjustment range of the braking effect and which has good performance even in case of extremely weakly and extremely strongly adjusted braking effects.
[0006] This object is achieved according to one embodiment by providing a yarn braking device for a yarn feeding device, the yarn braking device having an axially stiff, radially deformable braking body with the shape of a frustocone coat, the large diameter end of the braking body being set coaxially over a rounded withdrawal end of a drum-shaped storage body and being pressed resiliently against the withdrawal end from the small diameter end by an axial force defining the braking effect between the braking body and the withdrawal end. An axial force generator acting in the axial direction and a center device acting in the radial direction are also provided, respectively, between a stationary holder and the braking body. The axial force generator is formed by at least one pair of permanent magnets, the permanent magnets of which are aligned axially to each other by the centering device with an intermediate gap, and the centering device includes an axial sliding guiding system which is separated structurally and functionally from the pair of permanent magnets.
[0007] Pursuant to an additional embodiment of the invention, a yarn braking device for a yarn feeding device is provided, the yarn braking device having an axially stiff, radially deformable braking body with the shape of a frustocone coat, the large diameter end of the braking body being set coaxially over a rounded withdrawal end of a drum-shaped storage body and being pressed resiliently against the withdrawal end from the small diameter end by an axial force defining the braking effect between the braking body and the withdrawal end. An axial force generator acting in the axial direction and a centering device acting in a radial direction are also provided, respectively, between a stationary holder and the braking body. The axial force generator and the centering device at the same time are formed by at least one pair of permanent magnets, of which one inner permanent magnet is supported against the holder while the other outer permanent magnet of the pair is supported against the braking body, and the permanent magnets of the pair are aligned to each other via an intermediate gap and such that the direction of the action of the magnet force is inclined obliquely towards the axis of the yarn braking device. Further, the permanent magnets of the pair are generating both axial force components and also radial force components, respectively.
[0008] In accordance with the first embodiment, the pair of the permanent magnets operates without contact and with a function which is not liable to aging, to aggressive substances, to misalignments, does not tend to develop the force irregularly, and which assures a wide adjustment range for the braking effect. The pair of permanent magnets exclusively has to generate the resilient axial force which determines the braking effect while the needed centering of the frustocone coat braking body is carried out at the small diameter end section by the sliding guiding system. The produced centering effect is the same for all adjustments of the braking effect. Both functions, i.e. the generation of the axial resilient force and the axial guidance may by optimised respectively per se since these functions do not interfere with each other during the operation of the yarn braking device. The problem of lint collection and the negative influence of collected lint are eliminated. The structural construction of the yarn braking device is simple and results in high reliability as there are no liable mechanical spring components.
[0009] In the solution according to the second embodiment, the pair of permanent magnets at the same time forms the axial force generator and the centering device, i.e., the small diameter end of the braking body is supported without contact by magnet forces only, and at the same time is axially actuated against the storage body and is radially actuated from all sides in the direction towards the axis of the yarn braking device by radial force components of the magnet effect, and is centered accordingly. Since there is no mechanical contact the yarn braking device is characterised by a prompt and precise response behaviour. The at least one pair of permanent magnets in the yarn braking device forms, so to speak, a virtual or magnetic spring. The respective inner permanent magnet could be provided directly in the braking body or could be integrated even into the material of the braking body, respectively.
[0010] As it is decisive for the desired braking function that the precisely adjustable axial resilient force permanently actuates the always correctly centered frustocone coat braking body against the withdrawal end, the permanent magnets in the pair of permanent magnets could be provided such that they either repel or attract each other, and such that the available mounting space is optimally used.
[0011] In case of single pairs of permanent magnets at least three regularly distributed pairs should be provided.
[0012] Very uniform development of the force can be achieved by ring-shaped permanent magnets which co-act essentially on the same diameters or even on different diameters.
[0013] Alternatively, e.g. for weight reasons, more than three permanent magnet pairs each consisting of single permanent magnets could be distributed in circumferential direction. In this case either a provided axial sliding guiding system will form an anti-rotation mechanism for the permanent magnets within the pairs in order to always align the permanent magnets to each other, or the single permanent magnets could be designed such or/and arranged such that they automatically generate an anti-rotation effect by the magnetic co-action.
[0014] The support ring body of a specific embodiment in which the centering device simultaneously constitutes the anti-rotation mechanism, is held in an outer ring carrying at least three axial guiding pins which are distributed in circumferential direction. The support ring body carries either a ring-shaped permanent magnet or several single permanent magnets, respectively. The holder is formed with a ring section which is equipped with guiding sleeves for the guiding pins and which either is provided with a ring-shaped permanent magnet or with single permanent magnets in a multiple arrangement. Alternatively, the guiding pins also may be anchored in the ring section of the holder, while the guiding sleeves then will be provided in the outer ring. The guiding pins should penetrate the guiding sleeves with a weak slide fit.
[0015] In a further expedient embodiment the outer ring is formed at the inner side with a conical seat for the small diameter end of the braking body. The support ring body is a snap ring which is snapped into the outer ring in order to position the braking body in the seat. This is advantageous in terms of assembly and allows, if needed, a prompt and comfortable replacement of the braking body.
[0016] In a further expedient embodiment the support ring body is secured at a small diameter ring edge of a generally conical cage the large diameter end region of which either is equipped with a ring-shaped permanent magnet or with several single permanent magnets, respectively, and which surrounds the braking body with radial distance. The cage is loosely inserted into a support ring which either includes the other ring-shaped permanent magnet or several single permanent magnets, respectively, and which is provided with axial holder feet which are distributed in circumferential direction. The inner sides of the holder feet define axial sliding guiding surfaces for a counter guiding surface at the outer periphery of the large diameter end region. In the case of ring-shaped permanent magnets an anti-rotation mechanism is not needed. To the contrary, an anti-rotation mechanism may be expedient in case of single permanent magnet pairs, e.g. between the cage and the support ring or between the sliding guiding surfaces and the counter guiding surface. The counter guiding surface may be concavely rounded in an axial section of the cage such that an axially shiftable universal joint or ball joint is formed between the counter guiding surface and the axial guiding surfaces of the holder feet. The universal joint or ball joint, respectively, allows the operation movements of the radially deformable braking body without interference and properly centers the small diameter end of the braking body.
[0017] With a view to a comfortable assembly the holder feet are snap holders having an integrated predetermined bending elasticity for a snap fixation at the ring section of the holder. The cage and the holder feet offer sufficient intermediate spaces such that lint does not collect there, or such that access is provided at any time for cleaning purposes or for an inspection.
[0018] With a view to easy assembly the support ring body should be formed with an outside seat for the small diameter end section of the braking body. The seat is bounded on one side by a shoulder such that the support ring body can be snapped into the ring edge of the cage in order to position the braking body. The seat could be formed partially or in its entirety in the ring edge of the cage.
[0019] In a particularly expedient embodiment which operates without a mechanical axial sliding guiding system each outer single or the ring-shaped permanent magnet is arranged in relation to the axis on a larger diameter than each inner single permanent magnet or the inner ring-shaped permanent magnet. The permanent magnets of the pair or of the pairs, e.g. respectively repelling permanent magnets, co-operate such that forces are generated which are directed obliquely to the axis and such that radial force components of the forces can be used for the centering while the axial force components are used to generate the resilient axial force. The trick of arranging the outer permanent magnet or the outer permanent magnets, respectively, on a larger diameter than the inner permanent magnet or the inner permanent magnets, respectively, results in the effect that the inner permanent magnet in case of a displacement outwardly away from the axis will be exposed to an increasing counter oriented radial force component and then is pressed back with force again in the direction towards the axis. That means that the respective maximum centering radial force component only is generated then when the inner permanent magnet tends to displace outwardly. In this fashions the inner permanent magnet or the inner permanent magnets, respectively, are captured in the magnetic fields of the outer permanent magnets or the outer permanent magnet, respectively, provided that the braking body is contacting the withdrawal rim of the storage body under axial force. The small diameter end of the braking body remains properly centered even in case of forces which act radially outwardly and originate e.g. from the deflection of the yarn at the support ring body or from the passage of a knot.
[0020] In a preferred embodiment the repelling surfaces of the repelling permanent magnets of the pair which repelling surfaces face each other, are inclined obliquely with respect to the axis, even, preferably, are formed conically, and are at least substantially parallel to each other. The radial and the axial force components are generated already by this design of the permanent magnets.
[0021] In an expedient embodiment having two ring-shaped permanent magnets the permanent magnets may be conical rings having a rectangular or trapezoidal cross-section. Already by this form of the permanent magnets the direction of the magnetic action is inclined obliquely towards the axis of the yarn braking device and uniformly along the circumference such that the multiple effect of radial force components and of axial force components is achieved. The radial force components act counter to an outward displacement of the small diameter end and increase the stronger the more the small diameter end is displaced outwardly.
[0022] In an expedient embodiment having single permanent magnets in several pairs distributed along the circumference the outer single permanent magnets are offset in circumferential direction relative to the inner single permanent magnets such that each outer single permanent magnet is directed into the gap between adjacent inner single permanent magnets or vice versa. Since then each inner single permanent magnet at the same time is actuated by the magnetic forces of two outer single permanent magnets from different directions the co-acting permanent magnets automatically constitute a contact free magnetic anti-rotation protection mechanism. Also in this case the inner single permanent magnets ought to be arranged on a smaller diameter than the outer single permanent magnets in order to achieve the necessary centering and return functions.
[0023] In an expedient embodiment the support ring body carries the single inner permanent magnets or the ring-shaped inner permanent magnet, respectively. A conical support cage which grips over the small diameter end of the braking body and which is secured, preferably detachably, at the holder carries the single permanent magnets or the ring-shaped outer permanent magnet, respectively, on a carrying ring. This solution is of advantage with a view to easy manufacturing and easy assembly.
[0024] In a further expedient embodiment a cylindrical extension of the frustocone coat is formed at the small diameter end of the braking body. This measure avoids local overloads at the small diameter end when actuated by the axial force and allows a simple assembly e.g. by only tucking the braking body loosely into the support ring body.
[0025] In a further expedient embodiment an essentially cylindrical extension is provided at the support ring body. The cylindrical extension extends through the carrying ring of the support cage without contacting the carrying ring. This measure stiffens the support ring body and allows to limit the displacement of the braking body in an emergency case under extreme sideward displacement. During normal operation of the yarn braking device, however, there will not be any contact between the extension and the carrying ring.
[0026] It is important for the above-mentioned reasons that an intermediate distance is generated in the direction of the magnet action between the support ring body and the carrying ring of the support cage, the intermediate distance being at least as large as the size of the air gap between the permanent magnets.
[0027] An advantageous handling is achieved when the cylindrical extension of the support ring body at the end protruding beyond the carrying ring of the support cage is equipped with an outwardly directed catching projection, e.g. a ring flange the outer diameter of which is slightly larger than the inner diameter of the carrying ring. During assembly the support ring body first is put against resistance into the carrying ring. During the normal operation of the yarn braking device, i.e., as soon as the braking body abuts at the storage body, the catching projection does not engage at the carrying ring. However, during assembly or during transport, the engagement of the catching projection at the carrying ring assures that the support ring body and the braking body cannot fall out of the carrying ring.
[0028] The magnitude of the axial force of the axial force generator is adjusted by the axial position of the holder in relation to the withdrawal end of the storage body. In order to allow to change the adjusted magnitude of the axial force generated between the permanent magnets precisely and remotely controlled and without manual engagement at the adjustment device of the holder, in an expedient embodiment at least one coil is functionally associated to one of the permanent magnets of the axial force generator in order to allow to generate an auxiliary magnet force which is superimposed on the axial force by selectively supplying current to the coil. The auxiliary magnet force increases or reduces the axial force to a desired extent. So to speak, one of the permanent magnets provided anyway for the suspension of the braking body is used as an armature of a selectively controlled electromagnet. Since the permanent magnets generate a relatively strong axial force a coil and/or a moderate current may be sufficient, which are not particularly strong, to adjust in some cases only a weak increase or decrease of the axial force. The axial effect of the coil or of several coils can be amplified by correspondingly placed iron, preferably soft iron. This embodiment is particularly expedient for a knitting machine, in particular a circular knitting machine at which frequently many yarn feeding devices are installed and where during operation fluctuations in the quality of the knitted fabric may occur which promptly could be compensated for by a change of the braking effect or the knitting yarn tension, respectively. By means of the coils in the yarn braking devices then the axial forces can be changed independently from the value of the respective axial force in one group of or in all yarn feeding devices, respectively, such that by this measure and substantially at the same time the tensions in the knitting yarns are raised or lowered by essentially the same amount.
[0029] In a further embodiment the coil is arranged stationarily outside of the braking body and in association to the permanent magnet of the axial force generator which permanent magnet is supported at the braking body. In this case the permanent magnet provided anyway in the axial force generator is used without additional measures for this additional function.
[0030] In a further embodiment the coil is supported at the braking body and is functionally associated to the permanent magnet which is provided stationarily outside the braking body. The coil is lightweight such that the mass of the braking body remains low. The permanent magnet provided outside the braking body anyway is part of the axial force generator and can be used for this additional function without additional structural measures.
[0031] In a yarn braking device the braking body of which is arranged via a support ring body in a support cage the coil expediently is provided in the support cage or at the support ring body, respectively. Thanks to this placement the coil is located optimally close to the permanent magnet.
DESCRIPTION OF THE DRAWINGS
[0032] Embodiments of the invention will be explained with the help of the drawings. In the drawings is:
[0033] FIG. 1 is a side view, in partial section, of a yarn braking device,
[0034] FIG. 2 is a sectional view in the section plane II-II in FIG. 1 ,
[0035] FIG. 3 is a sectional view in the section plane III-III in FIG. 2 ,
[0036] FIG. 4 is a perspective view of the yarn braking device of FIGS. 1 to 3 ,
[0037] FIG. 5 is a part of an axial sectional view of another embodiment of the yarn braking device,
[0038] FIG. 6 is a side view of a detail of the yarn braking device of FIG. 5 ,
[0039] FIG. 7 is a side view of a further detail of a yarn braking device of FIG. 5 ,
[0040] FIG. 8 is an axial section of a further embodiment of a yarn braking device,
[0041] FIG. 9 is a detail of FIG. 8 in enlarged scale and in an axial section,
[0042] FIG. 10 is a detail variant, in a section similar to FIG. 9 ,
[0043] FIG. 11 is an axial section of a detail indicated in FIG. 8 by a circle,
[0044] FIG. 12 is a perspective explosion illustration of the main components of the yarn braking device of FIG. 8 ,
[0045] FIG. 13 is another perspective view of a component of FIG. 12 ,
[0046] FIG. 14 is a schematic axial section of a further embodiment of a yarn braking device,
[0047] FIG. 15 is an axial section of a further embodiment of a yarn braking device,
[0048] FIG. 16 is a detail variant similar to FIGS. 9 and 10 , and
[0049] FIG. 17 schematically shows a detail variant of a further embodiment of a yarn braking device.
DETAILED DESCRIPTION
[0050] A first embodiment of a non-controlled yarn braking device B, shown in FIG. 4 in a perspective view, is explained with the help of FIGS. 1 to 4 . The yarn braking device B is mounted in a yarn feeding device F ( FIG. 1 ) comprising a drum-shaped stationary storage body 1 having a rounded withdrawal end 2 and an axis X which is also the axis of the yarn braking device B. A braking body K with the form of a frustocone coat 3 (having a straight line as a generatrice) is provided in the yarn braking device B. The braking body K is put with the large diameter end 4 over the withdrawal end 2 and is pressed against the withdrawal end 2 by an axially resilient force. The axially resilient force defines the braking effect for the yarn in the contact region between the inner side of the frustocone coat 3 and the withdrawal end 2 . During the withdrawal and the run through the yarn braking device the withdrawn yarn is circulating like the hand of a clock. The braking body K e.g. is made from plastic material with or without enforcement, from metal or from a mesh fabric or lattice fabric. In some cases an inner circumferentially continuous braking coating made of wear resistant material may be provided in the braking zone although the inner surface of the braking body K as well may be directly used for braking the yarn. The yarn braking body K is axially relatively stiff but radially easily deformable such that it embraces the withdrawal end 2 and is able to form a wave following the yarn which consequently revolves along the withdrawal rim. The deformability of the braking body K also allows to let knots pass through the braking zone.
[0051] A small diameter end 5 of the braking body K is secured in this embodiment at a support ring body 8 . The support ring body 8 has at the inner side a low friction and wear resistant surface for the contact with the yarn which is deflected in this location. The support ring body 8 is formed as a snap ring and is snapped into the inner side of an outer ring 7 . The outer ring 7 (or the support ring body 8 ) has a conical seat 6 for the small diameter end 5 of the yarn braking body K. The yarn braking body K is replaceably positioned loosely by the snapping effect between the support ring body 8 and the outer ring 7 .
[0052] In the yarn feeding device, which is not shown in detail, a holder 10 is supported stationarily with axial distance from the outer ring 7 . The holder can be adjusted parallel to the axis X. The holder has a ring section 11 forming a passing opening for the withdrawn yarn. A centering device C is provided between the holder 10 and the support ring body 8 which centering device C centers the small diameter end 5 of the yarn braking body on the axis X. In this embodiment, the centering device C, at the same time, constitutes an anti-rotation protection mechanism limiting or suppressing the relative rotation between the outer ring 7 and the holder 10 . Furthermore, an axial force generator P is provided ( FIG. 3 ) between the outer ring 7 and the holder 10 . The axial force generator P resiliently produces the axial force between the holder 10 and the yarn braking body K which axial force is decisive for the braking effect.
[0053] The centering device C in FIGS. 1 to 4 consists of several axial guiding pins 9 which are distributed in circumferential direction and, in this case, are anchored in the outer ring 7 . The guiding pins 9 are inserted with a weak slide fit into guiding sleeves 12 which are provided in the ring section 11 of the holder 10 . Expediently, a very small radial clearance is provided between the guiding pins 9 and the guiding sleeves 12 . The positions of the guiding pins 9 and the guiding sleeves 12 could be inverted as well.
[0054] The axial force generator P is constituted in this embodiment by repelling permanent magnets 13 , 14 which are aligned with each other pairwise and in axial direction. Single permanent magnets 13 are contained in pockets 16 of the outer ring, while pockets 15 at the ring section 11 which pockets 15 are axially aligned with the pockets 16 also contain single permanent magnets 14 .
[0055] The adjustment of the axial force between the permanent magnets 13 , 14 pressing the braking body K against the withdrawal end 2 is carried out by the axial positioning of the holder 10 relative to the withdrawal end 2 .
[0056] In the shown embodiment three guiding pins 9 are provided with equal distances (120°). The guiding pins 9 are structurally and functionally separated from the permanent magnet pairs. Furthermore, twelve regularly distributed (30°) permanent magnet pairs 13 , 14 are provided. The number of guiding pins 9 and/or of permanent magnet pairs as well may be selected differently.
[0057] Although this is not shown in FIGS. 1 to 4 , two ring-shaped, one-piece permanent magnets could be provided instead of several single permanent magnet pairs 13 , 14 . The ring-shaped permanent magnets could be made e.g. from a mass which is bonded by plastic material and which can be magnetised. In a further, not shown, modification of the embodiment of FIGS. 1 to 4 permanent magnet pairs could be used the permanent magnet of which pairs are attracting each other. This could be realised e.g. by placing a ring like the outer ring 7 on ends of the guiding pins 9 which ends extended beyond the holder 10 and by mounting other attracting permanent magnets at the ring. For example, neodymium permanent magnets or ferrite permanent magnets are particularly suitable.
[0058] A detail variant of the yarn braking device is indicated in dotted lines in FIG. 1 . A coil 39 which selectively can be supplied with current is magnetically and functionally associated to the permanent magnets 13 which transmit the axial force of the axial force generator P to the braking body K at the outer side such that with current supplied to the coil 39 an auxiliary magnet force 41 can be generated which has essentially the same or the opposite direction of action like the axial force by which auxiliary magnet force 41 the value of the axial force can be increased or decreased. The coil 39 e.g. is placed at a carrier 40 provided at the ring section 11 .
[0059] In the yarn braking device B in FIGS. 5 to 7 an anti-rotation protection mechanism is dispensed with in comparison to the embodiment of FIGS. 1 to 4 . The holder 10 is positioned with its ring section 11 ′ very close to the withdrawal end 2 of the storage body 1 at the yarn feeding device (not shown). By this arrangement mounting space is saved at the other side of support ring body 8 which is provided in some cases.
[0060] In this embodiment the braking body K is positioned with the small diameter end 5 in a conical seat 6 which is formed in this case in the support ring 49 . The seat is bounded by a shoulder 8 a . A generally conical cage 18 is supported on the shoulder 8 a via a ring edge 17 . The ring edge 17 is snapped into the seat 6 in order to secure the small diameter end 5 of the braking body K. The cage 18 is formed with a cone angle which is larger than the cone angle of the braking body K. Furthermore, the cage 18 is provided with several spokes emanating from the ring edge 17 and leading to a ring-shaped large diameter end region 20 . So to speak, the braking body K is sunk into the cage 18 at least with a part of its longitudinal extension.
[0061] The large diameter end region 20 of the cage 18 contains a ring-shaped permanent magnet 13 ′ which is aligned axially by the centering device on a further ring-shaped permanent magnet 14 ′. The ring-shaped permanent magnet 14 ′ is held in a support ring 21 . The support ring 21 has axial and regularly distributed holder feet 22 at the outer side extending in the direction of the large diameter end 4 of the braking body. The holder feet 22 are formed as snap holders with integrated predetermined bending elasticity and are snapped into the ring section 11 ′ of the holder 10 . Axial guiding surfaces 23 for co-action with a counter guiding surface 24 at the outer periphery of the large diameter end region 24 , e.g. formed with a circumferentially continuous extension, are provided at the inner walls of the holder feet 22 . The guiding surfaces 23 , 24 constitute the centering device C. The counter guiding surface 24 e.g. is convexly rounded as shown in order to create the function of an axially movable universal joint or ball joint, respectively, for centering the braking body K.
[0062] In a not shown modified embodiment of FIGS. 5 to 7 instead of the two ring-shaped permanent magnets 13 ′, 14 ′ several single permanent magnet pairs could be provided similar to FIG. 2 . In this case it is expedient to also integrate an anti-rotation protection mechanism into the centering device C, e.g. by means of a circumferential form fit co-action between the guiding surfaces 24 , 23 .
[0063] In the embodiment in FIGS. 5 to 7 respective repelling permanent magnets are provided. In a not shown modification instead respectively attracting permanent magnets could be used, e.g. by securing one permanent magnet ring at the upper end of the holder feet 22 which attracts the other ring-shaped permanent magnet which then is provided in the large diameter end region 20 . The cage 18 is loosely inserted with the braking body K into the structure defined by the holder feet 22 and the support ring 21 . A replacement of the braking body K is possible after detaching the holder feet 22 from the ring section 11 ′. In this case either the braking body K is changed together with the cage 18 as one unit, or only the braking body K is replaced after detaching the support ring body 8 from the ring edge 17 , respectively.
[0064] The spokes 19 ( FIG. 6 ) of the cage 18 allow permanent visual inspection or cleaning of the inner components, because the holder feet 22 form large dimensioned intermediate spaces. Except the permanent magnets all components of the yarn braking device could be plastic form parts. This is true also for the embodiment of FIGS. 1 to 4 .
[0065] A detail variant of the yarn braking device B is indicated by dotted lines in FIG. 5 . At least one coil 39 is provided in the holder feet 22 such that it co-acts magnetically with the permanent magnet 13 ′ when current is supplied. The coil 39 superimposes an auxiliary magnet force to the axial force generated between the permanent magnets 13 ′, 14 ′. The auxiliary magnet force either has the same or the opposite direction of action as the axial force. The coil 39 in FIG. 5 is arranged such that it generates an auxiliary magnet force 41 which increases the axial force when the coil 39 is under current.
[0066] In the embodiments of FIGS. 8 to 17 the axial force generator P and the centering device C at the same time are formed free of contact by the permanent magnet pairs. The permanent magnets (either two rings or several pairs of single permanent magnets distributed in circumferential direction) co-operate with a magnet effect which is directed obliquely to the axis X. Preferably, respectively repelling permanent magnets are used, although (not shown) respectively attracting permanent magnets could be used if arranged accordingly.
[0067] The axial section in FIG. 8 shows the operative position of the yarn braking device B with the yarn braking body K axially resiliently pressed against the withdrawal rim 2 of the storage body 1 . The support ring body 8 is provided in the small diameter end of the yarn braking body K. The support ring body 8 optimally may be formed with a cylindrical extension. The support ring body 8 carries at the outer side the ring-shaped permanent magnet 13 ′ to which a ring-shaped permanent magnet 14 ′ is aligned essentially axially. The ring-shaped permanent magnet 14 ′ is held in a support cage. As will be explained with the help of FIGS. 9 , 10 and 16 , in this case the repelling permanent magnets 13 ′, 14 ′ are arranged such, and/or are constructed such, that the magnet effect is directed obliquely to the axis X of the yarn braking device B and such that by the magnet effect inwardly directed radial force components and axial force components in the direction towards the storage body are generated. The permanent magnet 13 ′ could be directly provided at the braking body K or could be integrated in the material of the braking body K, respectively (e.g. made from magnetplast).
[0068] The support cage 26 shown in FIG. 9 only partially (with intermediate spaces between the spokes 27 ) has a circumferential continuous carrying ring 37 at the smaller end. The ring-shaped permanent magnet 14 ′ formed as a conical ring of trapezoidal cross-section is positioned inside the carrying ring 37 such that a flat or conical repelling surface (the broader base of the trapezoid) is inclined relative to the axis with an angle which e.g. amounts to about 45°. The ring-shaped permanent magnet 13 ′, also being a conical ring having trapezoidal cross-section and a flat or conical repelling surface at the broader base of the trapezoid is aligned essentially axially to the ring-shaped permanent magnet 14 ′. The permanent magnet 13 ′ is secured in the support ring body 8 the cylindrical extension 29 of which extends without contact through the carrying ring 37 . An air gap is formed between the repelling surfaces of the permanent magnets 13 ′, 14 ′. The radial distance between the extension 29 and the carrying ring 37 is essentially as large as the width of the air gap. A catching projection 38 is formed at the free end of the extension 29 , e.g. a hook-shaped outer flange, the outer diameter of which is slightly larger than the inner diameter of the carrying ring 37 . The support ring body 8 consists of elastic material, e.g. plastic material. The elasticity of the material allows to introduce the catching projection 38 into the carrying ring 37 by overcoming a certain resistance. However, the support ring body 8 only can be pulled out from the carrying ring 37 with significant force and such that it cannot fall out later by itself from the carrying ring 37 or the support cage 26 , respectively.
[0069] The braking body K is equipped at the small diameter end 5 with a cylindrical extension 5 ′ which is connected to the small diameter end 5 via an inwardly rounded shoulder such that a rounded yarn deflection shoulder 5 ″ is formed which is lined with the material of the braking body K. Furthermore, a seat 30 for the yarn braking body K is formed in the support ring body 8 . The yarn braking body K either is only inserted loosely into the support ring body 8 such that in case of a needed replacement of the braking body K the support ring body 8 can be re-used, or in some cases may be bonded, e.g. glued to the support ring body 8 .
[0070] Due to the essentially parallel repelling surfaces of both permanent magnets 13 , 14 which both are inclined obliquely the repelling force acts obliquely to the right side and downwards to the axis X such that the axial force for pressing the braking body K against the withdrawal rim 2 and at the same time the radial force components for centering the small diameter end 5 of the braking body K are generated by the magnet effect and such that no mechanical contact occurs between the support ring body 8 and the carrying ring 37 .
[0071] Dotted lines in FIG. 9 indicate that two coils 39 , which may be supplied with current selectively, are situated in the small diameter end of the support cage 26 such that they are functionally associated to the permanent magnet 13 ′ and that they generate an auxiliary magnet force at the permanent magnet 13 ′ when supplied with current. As an alternative, to the contrary, the coil 39 ′ as well could be placed at the braking body K or the support ring body 8 , respectively, and could be functionally associated to the stationary permanent magnet 14 ′, in order to generate the necessary auxiliary magnet force.
[0072] As the yarn braking device B does not need a mechanical centering device or axial guiding device, respectively, when the permanent magnets 13 ′, 14 ′ as well constitute the centering device C, the support ring body 8 in the embodiment of FIG. 10 is formed without a cylindrical extension 29 as shown in FIG. 9 . With this measure the moving masses are reduced. The support ring body 8 may form the shoulder region 5 ″ for deflecting the yarn. The braking body K is inserted with the small diameter end 5 directly into the seat 30 of the support ring body 8 , in some cases only loosely, or in other cases bonded thereto. Both permanent magnets 13 ′, 14 ′ are co-operating in this case on the same diameter d on which, so to speak, the magnetic force centers of both permanent magnets 14 ′, 13 ′ are situated.
[0073] FIG. 11 illustrates the detachable fixation of the support cage 26 in a ring body 11 of the not shown holder 10 . The ring body 11 has a flange 32 with insertion openings 33 for latching tongues 35 of the support cage 26 . The latching tongues 35 are hooked in easily detachable fashion behind a shoulder.
[0074] The exploded illustration in FIG. 12 shows the arrangement of the main components of the yarn braking device e.g. of FIGS. 8 and 9 with the support cage 26 having the spokes 27 , the latching tongues or latching hooks 25 and the carrying ring 37 , the support ring body 8 having the extension 29 and finally the braking body K having the cylindrical extension 5 ′ shown in FIG. 9 . The inner ring-shaped permanent magnet 13 ′ is fixed at a shoulder region of the support ring body 8 , e.g. by gluing or by a snap fit.
[0075] FIG. 13 illustrates the positioning of the outer ring-shaped permanent magnet 13 ′ on the inner side of the carrying ring 37 of the support cage 26 . The permanent magnet 14 ′ as well either is glued in or is snapped in. Since the support ring body 8 and the support cage 26 may be injection moulded parts of plastic material the permanent magnets 13 ′, 14 ′ even may be embedded and positioned during by the injection moulding process. The coil 39 (in some cases even several coils) may be placed inside the support cage 26 .
[0076] FIG. 16 shows a modified detail variant of the yarn braking device of FIGS. 8 , 9 and 10 . The outer ring-shaped permanent magnet 14 ′ has a larger diameter d 2 and the inner ring-shaped permanent magnet 13 ′ has a smaller diameter d 1 . The further design corresponds with the design as explained with the help of FIGS. 9 and 10 . The permanent magnets 13 ′, 14 ′ repel each other. Since the outer permanent magnet 14 ′ is acting on the diameter d 2 which is larger than d 1 , the radial component of the repelling force increases when the small diameter end 5 of the braking body K in FIG. 16 e.g. tends to become displaced upwardly such that an expanded radial range exists within which the inner permanent magnet 13 ′ is forced back and centered by the outer permanent magnet 14 ′. This returning force action is the stronger the more the inner permanent magnet 13 ′ is displaced upwardly.
[0077] In the embodiment of the yarn braking device B shown in FIG. 14 two ring-shaped permanent magnets 13 ′, 14 ′ (repelling permanent magnets) are provided in the form of conical rings having a rectangular cross-section. The permanent magnets 13 ′, 14 ′ at the same time constitute the axial force generator P and the centering device C.
[0078] The embodiment in FIG. 15 contains two ring-shaped (conical ring) permanent magnets 13 ′, 14 ′ having rectangular cross-sections (respectively repelling permanent magnets). The outer permanent magnet 14 ′ is provided on a larger diameter d 2 while the inner permanent magnet 13 ′ is provided on a smaller diameter d 1 , in order to achieve, as explained for FIG. 16 , a larger radial range within which the inner permanent magnet 13 ′ in case of a displacement is returned into the centered position by the increasing force from the outer permanent magnet 14 ′.
[0079] The principle of the magnet effect which acts obliquely to the axis X of the yarn braking device cannot only be realised with ring-shaped permanent magnets, but also can be achieved as shown in FIG. 17 even with single permanent magnets 13 , 14 which e.g. may be cylindrical discs or cuboid-shaped blocks, respectively. The permanent magnets 13 , 14 respectively are distributed pairwise around the circumference of the yarn braking device. The inner single permanent magnets 13 are connected e.g. to the carrying ring 37 or to another holding means. The permanent magnets 13 , 14 are aligned to each other such that the magnet effect is directed obliquely, e.g. towards a point of intersection 36 to the axis X in order to generate the axial force and at the same time the radial force components. The permanent magnets 14 expediently are arranged at a larger diameter d 2 than the inner permanent magnets 13 . In order to prevent the permanent magnets 13 , 14 being rotated in relation to each other about the axis X the permanent magnets 13 , 14 are offset in circumferential direction such that they face the respective gaps between two adjacent other permanent magnets. That is, each permanent magnet 13 at the same time is actuated magnetically and obliquely with forces from two outer permanent magnets 14 . A gap between the outer permanent magnets 14 e.g. is indicated with reference numeral 34 . The inner single permanent magnet 13 is aligned to this gap 34 . The directions of the actions between the outer and the inner permanent magnets 13 , 14 need not be directed to the same point of intersection 36 on the axis X, but the directions of the actions of the outer repelling permanent magnets 14 as well could intersect the axis X further to the left side than at the point of intersection 36 . Thanks to this arrangement the co-acting permanent magnets 13 , 14 constitute the axial force generator P and the centering device, in particular, without any mechanical contact, and as soon as the braking body K is pressed against the storage body 1 . The permanent magnets 13 could be provided directly at the braking body K or could even be integrated into the material of the braking body K, respectively.
[0080] The coil or the coils 39 , 39 ′ expediently are connected to a current control device and a current adjusting device. In order to improve the action of the coil iron material, in particular soft iron could be placed in the vicinity of the coil. In case that a circular knitting machine having many such yarn feeding devices which are equipped with such yarn braking devices B, all coils 39 , 39 ′ expediently could be controlled by a central current control device and current adjustment device in order to change the axial forces in the yarn braking devices of those yarn feeding devices jointly and independent from the value of the respective pre-adjusted axial force by an e.g. equal amount. In this fashion a trend to a deterioration of the quality of the knitted fabric, caused by a drift or fluctuation of the knitting yarn tension can be compensated for comfortably. | The invention relates to a yarn tensioning device (B) comprising a braking body (K) embodied in the form of a truncated conical jacket ( 3 ) which is coaxially positioned on the rounded discharge end ( 2 ) of a storage body ( 1 ) and is pushed to a small diameter end ( 5 ) by the elastic axial force defining a braking effect between the braking body and the discharge end ( 2 ), an axial force generator (P) disposed between a fixed holding element ( 10 ) and the braking body and a centering device (C) provided with a radial working direction and disposed between the holding element ( 10 ) and the braking body, wherein said axial force generator (P) consists of at least one pair of axially superimposed permanent magnets, an intermediate slit is arranged between said permanent magnets and the centering device (C) which is embodied in the form of a axial slide guideway ( 9, 12, 24, 23 ) which is structurally and functionally separated from the permanent magnet pair or contactlessly formed thereby. | 3 |
FIELD OF THE INVENTION
[0001] The present invention relates to linear compressors, and in particular linear compressors of the type suitable for use in a vapour compression refrigeration system.
BACKGROUND TO THE INVENTION
[0002] Linear compressors of a type for use in a vapour compression refrigeration system are the subject of many documents in the prior art. One such document is our co-pending PCT patent application PCT/NZ2004/000108. That specification describes a variety of developments relating to such compressors, many of which have particular application to the linear compressors. The present invention relates to further improvements to compressor embodiments such as are described in that patent application which provides a general exemplification of a compressor to which the present invention may be applied. However the present may also be applied beyond the scope of the particular embodiments of a linear compressor disclosed in that application. Persons skilled in the art will appreciate the general application of the ideas herein to other embodiments of linear compressors such as are found in the prior art.
SUMMARY OF THE INVENTION
[0003] It is an object of the present invention to provide improvements relating to linear compressors or to at least provide the industry with a useful choice.
[0004] In a first aspect the invention may broadly be said to consist in a linear compressor comprising:
[0005] a cylinder part including a cylinder bore,
[0006] a piston disposed in said bore and slidable therein,
[0007] a main spring connecting directly or indirectly said cylinder part to said piston,
[0008] a connecting member connecting between said main spring and said piston,
[0009] a stator having an air gap, said connecting member passing through said air gap, and
[0010] one or more substantially flat blocks of permanent magnet material secured to said connecting member with the large faces of said blocks facing the stator, said permanent magnet material magnetised to define at least one armature pole; and wherein said main spring comprises a combination of a plurality of individual spring elements acting in parallel.
[0011] In a further aspect the invention may broadly be said to consist in a linear compressor comprising:
[0012] a cylinder part including a cylinder bore,
[0013] a piston disposed in said bore and slidable therein,
[0014] a main spring connecting directly or indirectly said cylinder part to said piston,
[0015] a connecting member connecting between said main spring and said piston,
[0016] a stator having an air gap, said connecting member passing through said air gap, and
[0017] at least one armature pole located along said connecting member,
[0018] wherein said connecting member is supported only by said piston at one end and by said main spring away from said one end, and said main spring comprises a combination of individual spring elements acting in parallel.
[0019] In a still further aspect the invention may broadly be said to consist in a linear compressor comprising:
[0020] a cylinder part including a cylinder bore,
[0021] a piston disposed in said bore and slidable therein,
[0022] a main spring connecting directly or indirectly said cylinder part to said piston, and
[0023] a connecting member connecting between said main spring and said piston, with a compliant element in said connecting member transmitting side and axial loads but allowing rotation about axes transverse to the axis of reciprocation of said piston in said bore;
[0024] wherein said main spring comprises a combination of a plurality of individual spring elements acting in parallel.
[0025] In relation to the invention as set forth in any of the above paragraphs said main spring may for example comprise a combination of coil springs, a combination of coil springs and planar springs or a combination of planar springs. Coil springs may be formed from suitable high fatigue wire or springs machined from thin walled cylinder stock. Preferably the combination includes at least one planar spring element contributing higher lateral stiffness. Most preferably the combination includes at least one planar spring and at least one coil spring.
[0026] In a still further aspect the invention may broadly be said to consist in a linear compressor comprising:
[0027] a cylinder part including a cylinder bore,
[0028] a piston disposed in said bore and slidable therein,
[0029] a main spring connecting directly or indirectly said cylinder part to said piston,
[0030] a connecting member connecting between said main spring and said piston and connecting said main spring to said piston,
[0031] a stator having an air gap, said connecting member passing through said air gap,
[0032] one or more substantially flat blocks of permanent magnet material secured to said connecting member with the large faces of said blocks facing the stator, said permanent magnet material magnetised to define at least one armature pole, and
[0033] a lateral support acting between said cylinder part and said connecting member, at a location intermediate said permanent magnet material and said piston, said lateral support allowing axial movement of said connecting rod, but transferring side loads to said cylinder part.
[0034] In relation to the invention as set forth in the above paragraph said main spring may comprise a single spring element or a combination of a plurality of spring elements acting in parallel. Preferably the main spring also provides lateral support acting between said cylinder part and said connecting member, at a location such that said armature pole or poles are between said main spring location and said lateral support located so that the armature of said motor is supported at one end by said main spring and at the other end by said lateral support.
[0035] According to a further aspect of the invention, said lateral support comprises one or more planar springs, for example cut from sheet material or formed from spring wire bent into a spring line within a plane. Alternatively said radial support may comprise one or more sliding bearings acting on the connecting member.
[0036] According to a further aspect of the invention, in the region of the connecting member between the lateral support and the piston the connecting member is laterally flexible or includes one (or preferably two) flexible portion, so as to effectively transmit axial forces but to have lateral and angular compliance of the piston relative to the axis and line of reciprocation of the connecting member.
[0037] The cylinder part may include provision for aerostatic gas bearings receiving compressed gases and supplying these through a plurality of spaced bearing ports spaced along and around the cylinder bore to support the piston in operation. However the armature radially (or laterally) supported at both ends and compliancy in the connecting member between the lateral support and the piston the inventors expect that the benefits of the gas bearings and reduced friction may be exceeded by the consumption of compressed gas in the gas bearings.
[0038] To those skilled in the art to which the invention relates, many changes in construction and widely differing embodiments and applications of the invention will suggest themselves without departing from the scope of the invention as defined in the appended claims. The disclosures and the descriptions herein are purely illustrative and are not intended to be in any sense limiting.
BRIEF DESCRIPTION OF THE DRAWINGS
[0039] FIG. 1 is a plan elevation in cross-section of a linear compressor according to a first embodiment. The first embodiment has a main spring comprising a combination of a flat spring and a coil spring. The flat motor armature is radially supported at one end by the main spring and at the other end by the piston. FIG. 1 is a cross-section taken through line DD of FIG. 2 .
[0040] FIG. 2 is a side elevation in cross-section of the embodiment of FIG. 1 , taken through line CC of FIG. 1 .
[0041] FIG. 3 is a plan elevation in cross-section of a linear compressor according to a second embodiment. The second embodiment has a main spring comprising a stack of flat springs. The flat motor armature is radially supported at one end by the main spring and at the other end by another flat spring. There is a compliant connection to the piston. FIG. 3 is a cross-section taken through line EE of FIG. 4 .
[0042] FIG. 4 is a side elevation in cross-section of the embodiment of FIG. 2 , taken through line BB of FIG. 3 .
[0043] FIG. 5 is a plan elevation in cross-section of a linear compressor according to a third embodiment. The third embodiment has a main spring comprising a combination of a flat spring and a coil spring. The flat motor armature is radially supported at one end by the main spring and at the other end in a sliding bearing. There is a compliant connection to the piston.
[0044] FIG. 5 is a cross-section taken through line FF of FIG. 6 .
[0045] FIG. 6 is a side elevation in cross-section of the embodiment of FIG. 5 , taken through line AA of FIG. 5 .
DETAILED DESCRIPTION
[0046] Referring to FIGS. 1 to 6 the compressor for a vapour compression refrigeration system includes a linear compressor 1 supported inside a housing 2 . Typically the housing 2 is hermetically sealed and includes a gases inlet port 3 and a compressed gases outlet port 4 . Uncompressed gases flow within the interior of the housing surrounding the compressor 1 . These uncompressed gases are drawn into the compressor during intake stroke, compressed between the piston crown 14 and valve plate 5 on the compression stroke and expelled through discharge valve 6 into a compressed gases manifold 7 . Compressed gases exit the manifold 7 to the outlet port 4 in the shell through a flexible tube 8 . To reduce the stiffness effect of discharge tube 8 , the tube is preferably arranged as a loop or spiral transverse to the reciprocating axis of the compressor. Intake to the compression space may be through the piston (with an aperture and valve in the crown) or through the head, divided to include suction and discharge manifolds and valves. The illustrated compressors have suction through the head, with suction manifold 13 and suction valve 29 .
[0047] The illustrated linear compressor 1 has, broadly speaking, a cylinder part and a piston part connected by a main spring. The cylinder part includes cylinder housing 10 , cylinder head 11 , valve plate 5 and a cylinder 12 . The cylinder part also includes stator parts 15 for a linear electric motor. An end portion 18 of the cylinder part, distal from the head 11 , mounts the main spring relative to the cylinder part. In the embodiment illustrated in FIGS. 1 and 2 and the embodiment illustrated in FIGS. 5 and 6 , the main spring is formed as a combination of coil spring 19 and flat spring 20 . In the embodiment illustrated in FIGS. 3 and 4 the main spring comprises a stack of a plurality of planar springs 16 .
[0048] The piston part includes a hollow piston 22 with sidewall 24 and crown 14 . A rod 26 connects between the crown 14 and a supporting body 30 for linear motor armature 17 . The linear motor armature 17 comprises a body of permanent magnet material (such as ferrite or neodymium) magnetised to provide one or more poles directed transverse to the axis of reciprocation of the piston within the cylinder liner. An end portion 32 of armature support 30 , distal from the piston 22 , is connected with the main spring.
[0049] In the embodiment of FIGS. 1 and 2 the rod 26 has a flexible portion 28 , located at approximately the centre of the hollow piston 22 . In the embodiment of FIGS. 3 and 4 and the embodiment of FIGS. 5 and 6 the rod 21 is narrow over its whole length.
[0050] The linear compressor 1 is mounted within the shell 2 on a plurality of suspension springs to isolate it from the shell. In use the large outer body of the linear compressor, the cylinder part, will oscillate along the axis of reciprocation of the piston part within the cylinder part. In the preferred compressor the piston part is purposely kept very light compared to the cylinder part so that the oscillation of the cylinder part is small compared with the relative reciprocation between the piston part and cylinder part. In the illustrated form the linear compressor is mounted on a set of four suspension springs 31 generally positioned around the periphery. Alternate suspension spring arrangements are illustrated in PCT/NZ2004/000108. The ends of each suspension spring fit over elastomeric snubbers connected with the linear compressor 1 at one end of each spring and connected with the compressor shell 2 at the other end of each spring.
[0051] Referring to the compressor embodiment of FIGS. 1 and 2 , this illustrates a variation of a compressor of a type disclosed in our earlier patent application, PCT/NZ2000/000201. In that application we disclosed a compressor including a linear motor with a substantially flat permanent magnet armature operating in an air gap of a stator carried by the cylinder part. The flat armature was positioned part way along a connecting member extending from the piston, to one side of the stator, to the main spring, on the other side of the stator. The connecting member, and therefore the side forces exerted by the linear electric motor, were laterally supported at one end by the piston within the cylinder and at the other end by the lateral stiffness of the main spring.
[0052] In that earlier PCT application we disclosed a main spring of substantially singular construction involving a double helical loop of heavy gauge high fatigue strength steel wire. This main spring provides sufficient lateral stiffness and appropriate axial stiffness in a single essentially unitary element, but is not a stock item and is complex to manufacture.
[0053] In one aspect the present invention is a variation of main spring involving a plurality of separate spring elements working in combination. For example in the embodiment of FIGS. 1 and 2 and the embodiment of FIGS. 5 and 6 the main spring comprises a combination of a coil spring 19 and a planar spring 20 . The planar spring 20 provides the lateral stiffness, while the coil spring 19 may add any desired additional axial stiffness. The planar spring 20 may be of any conventional form, for example cut from a spring steel sheet, or may be of a form such as illustrated in our earlier patent application, PCT/NZ2000/000202.
[0054] Another embodiment is disclosed with reference to FIGS. 3 and 4 in which the main spring comprises the combined stack of four planar springs 16 all operating together. In this case each of the planar springs offers both lateral stiffness and axial stiffness. Planar springs are generally very stiff laterally compared with their axial stiffness and an embodiment as illustrated in FIGS. 3 and 4 will probably exhibit unnecessarily high lateral stiffness to obtain a suitable axial stiffness, although it would be appreciated that the desired axial stiffness will depend on the desired running speed for the compressor.
[0055] The embodiments of FIGS. 3 and 4 and FIGS. 5 and 6 illustrate a further aspect of the present invention. In the compressor embodiment of FIGS. 1 and 2 and in the aforementioned patent application PCT/NZ2000/000201, the piston rod, carrying the armature 17 , is supported against lateral loading by the main spring at one end and through the piston at the other end. This is desirable for its compactness and simplicity however it does result in increased side loading of the piston within the cylinder bore. This extra side loading can be managed and examples of how to manage it are given in our patent applications, including in relation to the embodiment of FIGS. 1 and 2 herein.
[0056] However the embodiments of FIGS. 3 and 4 and 5 and 6 herein provide an alternative approach to dealing with the lateral forces resulting from the flat permanent magnet linear motor, where the motor is located on the member connecting between the main spring and the piston.
[0057] According to this aspect of the invention a radial or lateral support is provided to act between the cylinder part 1 and the connecting member at a location between the armature magnets and the piston. The support transmits the side loads from the connecting member directly to the cylinder part 10 .
[0058] In the embodiment of FIGS. 3 and 4 the radial support comprises a planar spring 40 connected at its outer edge 41 to said cylinder part 10 and at its hub 43 to an end 45 of the armature supporting body 30 . The planar spring 40 offers substantial lateral stiffness and the armature supporting body 30 is substantially rigid. Accordingly the lateral loads from the flat permanent magnetic linear electric motor, which can be substantial, are supported at one end by flat spring 40 and at the other by the main spring, which includes further planar springs 16 . The planar spring 40 may be mounted within an annular ring portion 42 of cylinder part 10 .
[0059] In an alternative embodiment illustrated in FIGS. 5 and 6 the lateral support is provided by an axial sliding bearing. The end portion 50 of armature support member 30 is formed to provide a substantially cylinder shaft of constant diameter. This shaft portion passes through a sliding bearing 52 forming part of the cylinder part 10 . The sliding bearing 52 may for example comprise a bush of a suitable low friction hardwearing material. The bush may for example be a spherical bush of PTFE plastic material (or similar) retained within a suitable internally spherical housing. This arrangement will also allow for certain misalignment of the armature support member 30 relative to the cylinder part 10 .
[0060] It is preferred in either case to retain reasonable gas flow in the vicinity of the armature. Accordingly an open frame construction, such as illustrated in FIGS. 4 and 5 , is used to support the lateral support (e.g. planar spring or sliding bearing) relative to the cylinder part 10 . Alternatively a plurality of windows or apertures, such as openings 56 in FIGS. 5 and 6 may be provided which communicate both with the region of the cylinder part housing the linear electric motor and with the region of the cylinder part housing the cylinder and piston. This gases flow capability into the inside of the cylinder part 10 is also useful to reduce any gas pressure effects on the back face of the piston 22 and to provide gas flow paths to the back face of piston 22 in embodiments where suction gases flow is provided through the crown of the piston rather than through the compressor head.
[0061] In the embodiments of FIGS. 3 to 6 where the armature supporting member 30 is fully supported against lateral loading, a preferred connection between the armature supporting member 30 and the piston 22 has considerable lateral compliancy while retaining axial stiffness. A suitable linkage would include a narrow metal rod embedded at one end in the end of the armature supporting member 30 and at the other end in the piston crown 14 . The thin rod 21 should have sufficient compliancy to allow the orientation of piston 22 to adapt to any misalignment between the armature support member 30 and the cylinder 12 , and sufficient axial stiffness that it will not buckle as the linear motor and springs drive the piston toward the cylinder head during the compression stroke of the compressor in operation.
[0062] While a compressor according to these embodiments, where the flat permanent magnetic armature is fully supported, may still provide for aerostatic gas bearings to operate between the cylinder 12 and piston 22 it is expected that the side loads from the piston 22 to the cylinder 12 will be very low. With modern hardware and coatings the arrangement may operate effectively and with sufficient longevity without either oil lubrication or aerostatic bearings. | A linear compressor ( 1 ) includes a cylinder ( 21 ) with a piston ( 22 ) connected through a main spring ( 19 ) and a planar spring ( 20 ). One or more flat blocks of permanent magnet material ( 17 ) with large faces of the blocks facing a stator ( 15 ) and defining armature poles are secured to a connecting rod ( 30 ). A lateral support ( 52 ) acts between the cylind ( 21 ) and the connecting rod ( 30 ) at a location midway between the permanent magnet material and the piston ( 22 ) allowing axial movement of the connecting rod ( 30 ) but transferring side loads to the cylinder ( 21 ). | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. application Ser. No. 09/901,836, filed Jul. 10, 2001, now U.S. Pat. No. ______, which is a continuation of application Ser. No. 09/000,133 filed Feb. 24, 1998, now U.S. Pat. No. 6,261,554, issued Jul. 17, 2001, which was a national filing under 35 U.S.C. §371 of PCT International Application PCT/NL96/00302 filed on Jul. 25, 1996, which itself claims priority from European Patent Application 95202040.2, filed Jul. 25, 1995, the contents of each of which are incorporated herein by this reference.
TECHNICAL FIELD
[0002] The present invention relates to the field of biotechnology, and to providing cells with additional genetic information through recombinant DNA techniques. It especially relates to methods and means of providing specific groups of cells with additional genetic information, in particular in the context of gene therapy.
BACKGROUND OF THE INVENTION
[0003] Gene therapy is a relatively recently developed concept having a very broad range of applications, ranging from supplementing deficiencies in a mammal's set of proteins, usually resulting from genetic disorders, to the treatment of cancer, (auto-)immune diseases or (viral) infections, usually by eliminating or suppressing the responsible set of cells or organisms.
[0004] One of the main problems in gene therapy is delivering the genetic material to the target cells and not to other cells. Another problem in gene therapy is that certain cell types are extremely refractory to current gene transfer techniques.
[0005] The present invention relates generally to gene delivery vehicles and their use in gene therapy and, more particularly, to recombinant viruses which can be targeted to susceptible target cells.
[0006] Retroviruses are RNA viruses which efficiently integrate their genetic information into the genomic DNA of infected cells via a reverse-transcribed DNA intermediate. This property of their life-cycle and the fact that parts of their genetic material can be replaced by foreign DNA sequences make retroviruses one of the most promising vectors for the delivery of genes in human gene therapy procedures, most notably for gene therapies which rely on gene transfer into dividing tissues. Most retroviral vector systems are based on mouse retroviruses and consist of two components, i.e., (i) the recombinant retroviral vector carrying the foreign sequences of interest, and (ii) so-called packaging cells expressing the structural viral proteins of which the encoding sequences are lacking in the retroviral vector. Expression of (i) in (ii) results in the production of recombinant retroviral particles capable of transducing susceptible target cells.
[0007] The infectivity and host cell range of the retrovirus particle is conferred by an envelope glycoprotein which specifically binds to a receptor molecule on the target cell membrane. The envelope glycoprotein of all known retroviruses consists of two associated peptides, which are derived by proteolytic cleavage from the same precursor protein encoded by the retroviral env gene (Dickson et al. in Weiss et al. (ed.) Molecular biology of tumor viruses (1984), Cold Spring Harbor Press, pp. 513-648). The amino terminal peptide encompasses the specific binding site for its receptor on the target cell membrane, thus determining the virus host range (Hunter and Swanstrom, Curr. Top. Microbiol. Immunol. 157(1990):187). The carboxy terminal peptide, which contains trans-membrane anchor sequences, is assumed to account for the selective uptake of the envelope glycoprotein in the virus particle and to mediate fusion between the virus membrane and—depending on the type of virus—the plasma membrane or intracellular vesicle membrane of the target cell.
[0008] Several envelope glycoprotein variants with different infection spectra for mammalian cells have been identified. All known env variants have a rather broad infection spectrum in common. Here lies one of the major shortcomings of current recombinant retrovirus technology. In numerous gene therapy applications, targeted delivery of genes into defined cells would be desired, most notably in the case of in vitro gene transfer into cell types present with low abundance in cell mixtures and in approaches for in vivo gene transfer into cells in a living mammalian body. Conventional gene transfer techniques have the disadvantage in such applications of low efficiency of gene transfer to desired target cells, because the gene transfer vehicles are taken up by other cells as well. In addition, the cell mixture or living mammalian body may contain cells to which gene transfer is absolutely undesired. E.g., genes providing protection against chemotherapeutic drugs should not be transferred into malignant cells. Therefore, increasing attention is focused on devising procedures to limit the retrovirus infection spectrum. By employing particular env variants the transduction spectrum can be limited to some extent, but true specificity for most target cells of interest can not be obtained this way. On the other hand, on the surface of some specific cell types, the expression of receptors for retroviral entry is extremely low. An important example of a cell type with low retrovirus receptor expression is the pluripotent stem cell of the hematopoietic system (Orlic et al., Blood 86 suppl 1 (1995):628a). A preferred strategy to accomplish targeted delivery is to direct the retrovirus particle to cell membrane molecules differing from the natural envelope glycoprotein receptor, the molecule being specifically expressed on the membrane of the desired target cell. Present ideas about how this could be done include:
1. direct chemical coupling of a ligand for a target cell molecule to the viral envelope glycoprotein (Neda et al, J. Biol. Chem. 266(1991):14143), 2. bridging the viral envelope glycoprotein to a molecule on the target cell through a complex of two antibodies, one directed against the viral envelope glycoprotein and the other against the molecule on the target cell (Goud et al., Virology 163(1988):251; Roux et al., Proc. Natl. Acad. Sci. USA 86(1989):9079; Etienne-Julan et al., J. Gen. Virol. 73(1992):3251), 3. bridging the viral envelope glycoprotein to a molecule on the target cell through a complex of an antibody directed against the viral envelope glycoprotein and a peptide ligand for the molecule on the target cell (Etienne-Julan et al.), 4. replacing the specific binding site of the viral envelope glycoprotein for its receptor by a peptide ligand for a target cell surface molecule, 5. co-expression on the virus membrane of the natural viral envelope glycoprotein and a ligand for a target cell surface molecule (Young et al., Science 250(1990):1421), and 6. co-expression on the virus membrane of the natural viral envelope glycoprotein and an altered viral envelope glycoprotein in which the specific binding site for its receptor has been replaced by a peptide ligand for a target cell surface molecule (Young et al.; Russell et al., Nucl. Acid Res. 5(1993):1081; Chu et al., Gene Ther. 1(1994):292; Kasahara et al., Science 266(1994):1373; Chu and Dornburg, J. Virol. 69(1995):2659).
[0015] Monoclonal antibodies or fragments thereof exhibiting high specificity and affinity for the target cell specific molecule are amongst the preferred ligands for targeted delivery. Approach nos. 2 and 3 mentioned above rely on antibodies and promising tools for use in the approach nos. 4 and 6 are chimaeric molecules between viral envelope glycoproteins and single-chain antibody fragments of the variable antigen-binding domain of immunoglobulins (scFv) (Russell et al., Nucl. Acid Res. 5(1993):1081; Chu et al., Gene Ther. 1(1994):292; Chu and Dornburg). A chimaeric molecule of such an scFv fragment and a different membrane anchoring protein than the viral envelope glycoprotein could be used for approach no. 5.
[0016] An important limitation of all these previous approaches is that a new virus with a specific targeting ligand (chemically or genetically modified envelope glycoprotein, or co-expressed ligand) or a new specific dual-antibody complex has to be made for each target cell type.
[0017] Adenovirus capsids are regular icosahedrons composed of 252 sub units, of which 240 are so-called hexons and 12 are so-called pentons. The pentons are located at the vertices of the icosahedron. They contain a penton base on the surface of the capsid which is composed of five molecules of a 85 kD polypeptide. A fiber composed of a homotrimer of 62 kD polypeptides projects from the penton base outward. The fiber protein is responsible for attachment of the adenovirus to its receptor (reviewed by Horwitz, in: Virology, 2nd edition (Fields et al, ed), Raven Press, New York, 1990, pp. 1679-1721). By exchanging fiber protein domains from two adenoviruses of different serotype, Stevenson et al. (J. Virol. 69(1995):2850) have shown that the receptor specificity is determined by the head domain of the fiber protein.
[0018] The adeno-associated virus (AAV) capsid is comprised of three viral proteins (VP): VP-1, VP-2, and VP-3. These proteins have molecular masses of 87 kD, 73 kD, and 62 kD, respectively. In mature virions VP-1, VP-2 and VP-3 are found at relative abundance of approximately 1:1:10. In vitro, the three proteins assemble spontaneously into virion-like structures. It appears, therefore, that capsid formation in infected cells proceeds independent of viral DNA synthesis (reviewed by Kotin, Hum. Gene Ther. 5(1994):793). It has been shown possible to insert sequences into the genes encoding the capsid proteins, resulting in the exposure of His-residues on the surface of intact AAV capsids. Consequently, these altered AAV virions were able to bind to a nickel-column (unpublished results from the group of Dr. R. Samulski, Univ. of North Carolina, Chapel Hill, N.C.).
BRIEF SUMMARY OF THE INVENTION
[0019] The present invention makes use of the possibility of inserting sequences in the capsid genes. The present invention thus provides a gene delivery vehicle for delivering genetic material to a target cell. The vehicle includes an expressible recombinant nucleic acid molecule encoding a gene product of interest, a capsid or an envelope derived from a virus, and a member of a specific binding pair, the counterpart of which is not directly associated with the surface of the target cell.
[0020] This gene delivery vehicle itself is preferably incapable of specifically binding to a target cell, meaning that it is no longer an infectious virus particle. Instead of having its regular infectivity, it is provided with a member of a specific binding pair, either as a part of its envelope or as a part of its capsid. This gene delivery vehicle in itself cannot be targeted to a target cell, but it is a novel and inventive intermediate in the process of preparing a targeting gene delivery vehicle, which together with a targeting component is capable of delivering a gene to target cells only, or at least of delivering genes to the target cells in a far greater amount than to non-target cells (or other targets, such as infectious organisms), or of delivering a gene to cells previously difficult to transduce as a result of low viral receptor expression. The invention thus also provides a targeting component which is a conjugate for use in targeting a gene delivery vehicle as disclosed above to a target cell, which conjugate comprises the counterpart of the member of a specific binding pair (which member is present on or in the gene delivery vehicle, which counterpart is coupled to a targeting moiety being capable of binding to a target molecule associated with the surface of a target cell.
[0021] Thus, the conjugate has dual specificity. On the one side, the counterpart recognizes the member of a specific binding pair present on or in the gene delivery vehicle and, on the other side, it recognizes a target molecule associated with the surface of the target cell. When such a conjugate is coupled to a gene delivery vehicle, a targeting gene delivery vehicle is obtained. Thus, the invention also provides a targeting gene delivery vehicle comprising a gene delivery vehicle as disclosed hereinabove, coupled to a conjugate as also described above.
[0022] The main advantage of the gene delivery vehicles according to the invention is that they have a recognizable moiety, which is independent from the target cell the genes have to be delivered to. This means that they can be targeted to many different target cells by using different conjugates which all recognize the vehicle (a constant part of the conjugate) and which recognize a number of different targets associated with target cells on the other side. Thus the gene of interest can be delivered to many different cells without having to prepare a new vehicle.
[0023] A similar approach has been disclosed and is described above as approach no. 3. In this approach, however, the vehicle has not been provided with an additional member of a specific binding pair, but a viral antigen (the envelope glycoprotein) itself is the member of a specific binding pair being recognized by an antibody. Apart from the drawback of having to make a new specific dual-antibody complex for every delivery system, an even more important drawback is that all antigens have to be bound to an antibody because, otherwise, the vehicle will retain its capability of infecting its regular host cells, whereas for the gene delivery vehicles according to the invention these glycoproteins are preferably (if not necessarily) not present or altered to impair their normal function.
[0024] In the following, it will become clear that preferred embodiments of the invention are so called “kits” (kits of parts) which provide a gene delivery vehicle as one part and at least one targeting moiety as another part.
[0025] Another part of the invention therefore is a kit of parts for delivering genetic material to a target cell, comprising a gene delivery vehicle according to the invention and at least one conjugate of the counterpart member of the specific binding pair coupled to a targeting moiety, the targeting moiety being capable of binding to a target molecule associated with the surface of a target cell.
[0026] The embodiments given above are the general formats of the invention. Thus, it is clear that the gene delivery vehicle itself, as well as the conjugate, the delivery vehicle coupled to the conjugate, and the kit comprising both the conjugate and delivery vehicle, all can be adjusted to the specific embodiments which are recited for the kits only. Thus, the specific conjugates without the delivery vehicle and the specific vehicles without the conjugates, as well as the specific targeting vehicles are part of this invention as well. For example, where a kit of parts is disclosed comprising as a member an immunoglobulin binding protein and as its counterpart an immunoglobulin, this means that the conjugate comprising the immunoglobulin is part of the invention, as is the gene delivery vehicle comprising the immunoglobulin binding protein. The definitions in the claims are themselves clearly understood in the art.
[0027] Specific binding pairs, for instance, are considered to be any two molecules which have a high affinity specific interaction between the two members (herein often referred to as the member and its counterpart). These may be antibody (fragments or derivatives) and the corresponding antigen, receptors and their ligands (in this case especially proteinaceous ligands), well known binding pairs such as avidin/biotin or streptavidin/biotin, peptide structures that can specifically interact in solution and the like. In many instances, members of these binding pairs will not be normally present in the envelope or the capsid of a virus and will thus also not be normally present on the gene delivery vehicles according to the invention. For that purpose, they may have to be modified in a suitable manner, for instance chemically, or they may need to be present as fusion molecules or hybrid molecules linked to a component which ensures their presence in or on the capsid or envelope. As long as they still have the same function (in kind, not in amount) as the original member of the binding pair (i.e., they still bind the counterpart) they should be considered as being a derivative or equivalent of the original member of the binding pair and are thus part of the present invention. The same goes for the counterpart of the member of the specific binding pair and also for the targeting moiety, which is the other side of the conjugate.
[0028] Herein, a number of possibilities of providing a capsid or an envelope with the function of a member of a specific binding pair are given, exemplified for the preferred vehicles, but skilled artisans will be able to transfer these teachings to other vehicles and/or other members of specific binding pairs, as well as other methods of providing these members on envelopes and/or capsids without departing from the present invention.
[0029] A conjugate is defined for the purposes of the present invention as any molecule which has at least two different specific recognition sites which are somehow linked. This means that it does not necessarily include chemical coupling or fusion proteins, although these are conjugates according to the invention, but that it also includes molecules which normally have this double specific recognition, such as, for instance, antibodies which recognize an antigen specifically and of which the constant region is specifically recognized by, for instance, Fc receptors.
[0030] A nucleic acid encoding a gene of interest should be interpreted as not only encoding proteins, but also antisense nucleic acids and other useful nucleic acids, although these are not usually considered to be genes. When the nucleic acids do encode proteins there are many known genes of interest in the field, particularly in the field of gene therapy. All these genes can be delivered to target cells using the methods and means of the present invention. Of particular interest are suicide genes, such as Herpes Simplex Virus Thymidine Kinase and others disclosed in PCT International Patent Application No. WO 93/07281, the contents of which are incorporated by this reference.
[0031] The target cells to which the genes of interest can be delivered are basically any target cells that have a target molecule associated with their surface with which it is possible to distinguish them from other cells using a targeting moiety. The ability to distinguish may lie in the abundance of a certain target molecule on a certain subset of cells. Furthermore, it is not necessary for the application of the invention that the nature of the target molecule is known. Targeting moieties can be selected from combinatorial peptide libraries on the basis of differential binding to molecules expressed on the surface of different cell types. Useful combinatorial peptide libraries for the invention include those in which a large variety of peptides is displayed on the surface of filamentous bacteriophages (e.g., Scott and Smith, Science 249(1990):386). Screening for individual library members that interact with desired target cells allows the isolation of the nucleotide sequences encoding suitable peptide structures to be used as a targeting moiety in the invention. For this purpose, libraries displaying scFv variants are particularly useful. Moreover, methods that increase the combinatorial diversity of the libraries make the number of targeting moieties that can be generated for application in the invention almost limitless. The methods include PCR-based random mutagenesis techniques (Stemmer, Proc. Natl. Acad. Sci. USA 91(1994):10747; Crameri and Stemmer, Biotechniques 18(1995):194). Thus, it is understood from the above that the invention discloses methods for specific gene delivery into any target cell that can be phenotypically distinguished from other cells, also when the nature of this distinction has not been revealed. Important target cells are tumor cells, cells of the hematopoietic system, hepatocytes, endothelial cells, lung cells, cells of the central nervous system, muscle cells and cells of the gastro-intestinal tract. Usual target molecules are receptors, surface antigens and the like.
[0032] As indicated above, the invention also includes a kit of parts wherein the member of a specific binding pair is an immunoglobulin binding moiety and its counterpart is an immunoglobulin or a derivative or a fragment thereof.
[0033] Preferably, the immunoglobulin binding moiety is capable of binding to a constant region of an immunoglobulin. A much preferred immunoglobulin binding moiety is protein A, protein G, or an Fc receptor. One of the most commonly used immunoglobulin-binding proteins is Staphylococcus aureus protein A. This 42 kD polypeptide exhibits strong binding to the Fc region of many IgG molecules, including human IgG1, IgG2 and IgG4 and mouse IgG2a and IgG2b, without interfering with the antigen binding site (Surolia et al., Trends Biochem. Sci. 7(1981):74; Lindmark et al, J. Immunol. Meth. 62(1983):1). A wider range of mammalian immunoglobulins is bound by protein G, which is isolated from a group C Streptococcus species. It has strong binding capacity for all human and mouse IgG subclasses (Bjork and Kronvall, J. Immunol. 133(1984):969; Sjöbring et al., J. Biol. Chem. 266(1991):399). Protein A and G do not intrinsically bind to mammalian cell surfaces or virus membranes or capsids. Expression of (parts of) these molecules on the surface of gene delivery vehicles will therefore require the generation of hybrid molecules. A hybrid between streptavidin and two of the IgG binding domains of protein A has been made and bound to one IgG molecule per hybrid (Sano and Cantor, Bio/Technol. 9(1991):1378).
[0034] The mammalian receptors for the Fc domain of immunoglobulins (FcR), however, are trans-membrane molecules (reviewed by Van de Winkel and Capel, Immunol. Today 14(1993):215). These receptors provide a feedback between the humoral and cellular immune responses. Their interaction with immunoglobulins triggers immune functions such as phagocytosis, cytotoxicity, cytokine release and enhancement of antigen presentation. FcR are members of the immunoglobulin superfamily and in humans three classes of receptors for the Fc domain of IgG (FcgR) are recognized (hFcgRI, hFcgRII, and hFcgRIII). hFcgRI is unique in its capacity to bind with high affinity to monomeric IgG (Ka=10 8 −10 9 M 1 ). Its binding is strong to human IgG3, IgG1, and IgG4 (with decreasing affinity), and to mouse IgG2a and IgG3, whereas human IgG2 and mouse IgG1 and IgG2b are bound much weaker. hFcgRI is constitutively expressed on monocytes and macrophages and its expression can be induced on neutrophils and eosinophils. Three highly homologous genes for hPcgRI have been identified. Of these, hFcgRIA encodes a trans-membrane molecule, hFcgRIa (a-chain), consisting of three extracellular immunoglobulin-like domains (one of which is not found among other members of the hFcgR-family), a 21 amino acid trans-membrane region, and a charged cytoplasmic tail of 61 amino acids. On the membrane of some cell types, the hFcgRIa a-chain is found associated with a disulfide-linked homodimer of g-chains, which are also components of other members of the FcR family (Scholl and Geha, Proc. Natl. Acad. Sci. USA 90(1993):8847). There exists some controversy whether the presence of g-chains is absolutely essential for membrane expression and ligand binding of the hFcgRIa a-chain (Takai et al, Cell 76(1994):519). The signal transduction after immunoglobulin binding to the a-chain into the interior of the cell is mediated by the g-chains; the cytoplasmic domain of the a-chain does not seem to play a role in signal transduction (Indik et al, Exp. Hematol. 22(1994):599).
[0035] Because the constant regions of immunoglobulins differ between species, anti-immunoglobulin antibodies can be generated by cross-species immunization. For several species, antibodies have been raised which show specificity to individual immunoglobulin chains or even subclasses. Molecular cloning of the sequences encoding these antibodies offers the possibility to construct scFv, which comprise the variable regions of the heavy and light chains of the immunoglobulin molecule linked by a flexible peptide bridge. Such scFv have been shown to be as potent in antigen binding as are immunoglobulin Fab fragments (Bird et al, Science 242(1988):423). Hybrid molecules between scFv and virus envelope molecules have been made and expressed on the surface of mammalian cells and were shown to be capable of antigen binding and targeted gene delivery (Chu et al, Gene Ther. 1(1994):292; Chu and Dornburg, J. Viral. 69(1995):2659).
[0036] When the gene delivery vehicle is provided with an immunoglobulin binding moiety, only a suitable antibody (or a derivative or a fragment (retaining the binding site for the immunoglobulin binding protein)) is needed as the entire conjugate. Thus, when an antibody is available which can distinguish a target cell from other cells, the gene delivery vehicle is ready to be used to target the gene of interest to the cell using the antibody. Thus, for any cell which can be distinguished from other cells using antibodies, a targeted gene delivery system is provided.
[0037] The same is true for another embodiment of the present invention in which the member of a specific binding pair is biotin and its counterpart is avidin or streptavidin, or in which the member of a specific binding pair is avidin or streptavidin and its counterpart is biotin. In this embodiment, the delivery vehicle is provided with the one member of the (strept)avidin/biotin couple and, thus, the conjugate comprises the other member.
[0038] Thus, any targeting moiety that can be biotinylated or can be coupled to (strept)avidin is now usable with the gene delivery vehicle according to the present invention. This makes the number of targeting moieties that can be applied almost limitless. Any molecule associated with the surface of a target cell for which a specific binding partner is known or can be produced is in principle useful as a target for the presently invented gene delivery system, if in presence or abundance it differs from one subset of cells to another. Antibodies, of course, are a good example of suitable targeting moieties of this last embodiment, as they were for the embodiment before that. Thus, a preferred embodiment of the present invention encompasses a kit of parts wherein the targeting moiety is an antibody or a fragment or a derivative thereof, recognizing the target molecule associated with the surface of the target cell.
[0039] Another group of suitable targeting moieties are ligands wherein the target molecule is a receptor (for which the targeting moiety is a ligand) associated with the surface of the cell.
[0040] For many cell type-specific antigens, protein ligands have been identified which bind with high specificity and/or affinity, e.g. cytokines binding to their cellular receptors. Most proteins can be labeled with the water-soluble vitamin biotin using simple procedures. Most biotinylations are performed using succinimide esters of biotin. Binding to the protein proceeds through free amino groups, normally of lysyl residues. Biotinylated molecules are bound with exceptionally high affinity (Ka=10 14 −10 15 M −1 ) by both avidin and streptavidin (Wilchek and Bayer, Immunol. Today 5(1984):39). Avidin is a 68 kD glycoprotein isolated from egg white and streptavidin is a 60 kD protein from Streptomyces avidinii . Both molecules are homotetramers; each subunit contains a single biotin binding-site. The high affinity of their binding makes the biotin-avidin or biotin- streptavidin interactions essentially irreversible. A functional streptavidin gene has been cloned (Sano and Cantor, Proc. Natl. Acad. Sci. USA 87(1990):142) and a streptavidin mutant has been generated (Sano and Cantor, Proc. Natl. Acad. Sci. USA 92(1995):3180) with reduced biotin-binding affinity (approx. Ka=10 8 M −1 ) providing specific and tight, yet reversible, biotin-binding. As for Protein A and G, avidin and streptavidin do not intrinsically bind to mammalian cell surfaces or virus membranes or capsids. Expression of (parts of) these molecules on the surface of gene delivery vehicles will therefore also require the generation of hybrid molecules. Hybrids of streptavidin and heterologous proteins have been made which retained full biotin binding capacity (Sano and Cantor, Bio/Technol. 9(1991):1378; Sano et al., Proc. Natl. Acad. Sci. USA 89(1992):1534).
[0041] In yet another embodiment of the invention, the member of the specific binding pair and its counterpart are both peptides forming three-dimensional structures that can interact in solution. Peptides useful in this aspect of the invention include, but are not restricted to, dimerization motifs that are identified within proteins known to form dimers, such as the yeast transcription factor GCN4, the mammalian transcription factor C/EBP, and the nuclear transforming oncogene products fos, jun, and myc. Alternatively, synthetic peptides can be used that are designed on the basis of the knowledge of inter and intra protein interactions. The paradigm of peptide motifs known to dimerize is the coiled-coil structure, a subset of which is the so called leucine zipper (Landschultz et al., Science 240(1988):1759; O'Shea et al., Science 243(1989):538; O'Shea et al., Science 254(1991):539). Several proteins containing a leucine zipper motif can not only form homodimers but also heterodimers (Hai et al., Genes & Dev. 3 (1989):2083; Roman et al., Genes & Dev. 4(1990):1404). The leucine zipper dimerization region itself contains all of the structural information determining the dimerization specificity (Agre et al., Science 246(1989):922; Kouzarides and Ziff, Nature 340(1989):568; O'Shea et al., Science 245(1989):646). For the design of the member of the specific binding pair and its counterpart in the present invention, it is preferred that the peptides used preferentially, if not exclusively, form heterodimers and not homodimers. Vinson et al (Genes & Dev. 7(1993):1047) have proposed and verified a rule for the rational design of leucine zipper motifs at preferentially formed heterodimers. Therefore, it is preferred that the peptides used in this aspect of the invention are designed according to this so called “i+5 salt bridge” rule. Expression of a dimerizing peptide motif on the surface of the delivery vehicle, as well as conjugation of its dimerizing counterpart to the targeting moiety, will require the generation of hybrid molecules. Many different hybrid proteins with functional leucine zipper domains have already been produced, including dimeric antibodies based on scFv (Pack and Plüickthun, Biochemistry 31(1992):1579), dimeric antibodies based on monoclonal Fab' fragments (Kostelny et al., J. Immunol. 148(1992):1547), and a set of heterodimerizing proteins with leucine zippers, one linked to phagemid pIII coat protein and the other linked to the products from a cDNA library, that can be used for the production of a combinatorial phagemid cDNA library (Crameri and Suter, Gene 137(1994):69).
[0042] When the gene delivery vehicle is provided with a peptide structure capable of dimerization with a counterpart in solution, it can be used in combination with any targeting moiety that can be coupled to the counterpart. Using standard techniques known in the art, expression constructs can be made for insertion of foreign sequences resulting in the translation of fusion proteins containing a leucine zipper terminal domain. The coupling may either be direct or via an intervening linker sequence separating the individual folding domains of the targeting moiety and counterpart. Linker sequences known in the art that provide the peptide main chain with conformational freedom, thereby separating individual folding domains, are usually rich in glycine residues. Examples of linker peptide sequences useful in the invention include, but are not restricted to (Gl 4 -Ser) 3 (Batra et al., J. Biol. Chem., 265(1990):15198) and (Gly 4 -Thr) 3 (Bird et al., Science 242(1988):423). It is thus understood from the above that also in this aspect of the invention the number of targeting moieties that can be applied is almost limitless.
[0043] As stated above, it is possible to target the gene delivery vehicles to many different cells using different conjugates (antibodies, biotinylated targeting moieties or targeting moieties conjugated to a peptide structure that can interact in solution). It is thus preferred to provide a kit of parts according to the invention comprising a multitude of different conjugates, comprising the same counterpart member but a number of different targeting moieties.
[0044] Although, as stated above, the skilled artisan will be able to apply the teaching of the present invention to other viruses than those exemplified herein, the exemplified viruses are preferred embodiments, because of the experience with the viruses in gene therapy concepts. Retroviruses are especially suitable for gene transfer into replicating cells. Foreign genes introduced by retroviruses become stable components of the genome of the target cell and its progeny. Adenoviruses, on the other hand, efficiently introduce foreign genetic material into non-dividing target cells. Adeno-associated virus is the only currently known non-pathogenic DNA-virus. It could provide an alternative for both retroviruses and adenoviruses in certain gene transfer applications. Thus, it is preferred that the gene delivery vehicle is derived from an adenovirus, an adeno associated virus or a retrovirus.
BRIEF DESCRIPTION OF THE DRAWINGS
[0045] FIG. 1 depicts the specific binding of biotinylated G-CSF to mouse fibroblasts expressing DG-CSFR on their membrane. FACS histograms of biotinylated G-CSF binding (log scale) are given. Solid lines represent measurement after incubation in biotinylated G-CSF, PE-Streptavidin, biotinylated goat-anti-Streptavidin, and PE-Streptavidin. Broken lines represent results of control incubations without biotinylated G-CSF. The percentage of cells showing specific binding of biotinylated G-CSF is shown in the upper right corner of each panel. Panel A: unmanipulated mouse fibroblasts, panel B: mouse fibroblasts transduced with LNCX-GRDcyt virus and selected with G418, panel C: mouse fibroblasts transduced with LNCX-GRDcyt virus, selected with G418, FACS sorted for GRDcyt expression and cloned by limiting dilution.
[0046] FIG. 2 depicts the levels of hFcgRIa expression on the membrane of PA317 cells during in vitro culture for up to eight weeks. Unmanipulated PA317 cells and two mixed populations of transfected PA317 cells which were FACS sorted for hFcgRIa expression (PAFcR sorted-315 and PAFcR sorted-216) were stained with the anti-FcgRI MoAb 22 or with an irrelevant anti-KLH isotype control. The ratios between the median signal intensities after staining with MoAb 22 over the control are given.
[0047] FIG. 3 depicts the structure of the two hybrid hFcgRIa/Mo-MuLV env molecules and their parental hFcgRIa and Mo-MuLV env proteins. The Mo-MuLV env peptides gp70 and p15E which are formed by proteolytic cleavage are shown separately and their physical connection on the precursor peptide is delineated by a broken line. Numbers above different segments indicate number of amino acids. Asterisks indicate position of Cys-residues. Arrows represent primers used for PCR amplification. Areas in FcRenv-15 and FcRenv-70 indicated with striped boxes underneath were made by PCR amplification. Positions of relevant restriction enzyme cleavage sites are indicated. Mo-MuLV env sequences are shown in grey, hFcgRIa sequences in white. Black boxes represent non-coding Mo-MuLV sequences. S, signal peptide; Pro, proline-rich hinge-like region; TM, trans-membrane spanning domain; C, cytoplasmic domain; EC1, EC2, EC3, extracellular domains 1, 2, and 3, each forming one immunoglobulin-like loop.
[0048] FIG. 4 shows in vitro immunoglobulin binding by hybrid hFcgRIa/Mo-MuLV env molecules FcRenv-15 and FcRenv-70. Positive and negative protein controls are wild type hFcgRIa (wt-FcR) and irrelevant firefly luciferase proteins, respectively. After in vitro coupled transcription and translation of the DNA sequences encoding these proteins, or a control reaction without DNA template (no DNA) in the presence of 3 H-labelled leucine, the formed proteins were precipitated with Sepharose beads loaded with IgG2a antibodies. The total reaction product (T), precipitated material (P) and precipitation supernatant (S) were separated through 10% SDS-polyacrylamide gel. The signal in the gel was amplified and exposed to an X-ray film. Extended exposures are indicated with a—above the bands. The molecular weights (MW) of a marker protein mixture are indicated at the right side of the gel.
DETAILED DESCRIPTION OF THE INVENTION
[0049] The present invention provides a method to universally exploit a recombinant virus preparation for the targeted delivery of genetic material to many different cell types. To this end, the invention describes methods for the production of recombinant viruses carrying on their surface molecules (members of a specific binding pair) which can specifically interact with a set of secondary molecules (conjugates comprising the counterparts of the members of a specific binding pair). The secondary molecules possess the ligand specificity for target cell-specific antigens. The indirect binding of the recombinant virus to the target cell via a single secondary molecule, which allows redirection of the same recombinant virus preparation to different target cells depending on the added secondary molecule, is a very important aspect of the invention. Useful secondary molecules to be employed in the invention include immunoglobulins or fragments thereof, chemically modified natural protein ligands for target cell antigens, fragments thereof, or recombinant derivatives thereof, and immunoglobulins, fragments thereof, recombinant derivatives thereof, natural protein ligands for target cell antigens, fragments thereof, or recombinant derivatives thereof that are coupled to a peptide motif that can interact with a specific counterpart in suspension. Biotinylation is the paradigm for the chemical modifications which could be employed. Typically, the specificity of the secondary molecules for the target cell antigen is high and, preferably, the affinity of the secondary molecules for the target cell antigen is high. Example 1 describes the specific interaction between a cytokine receptor molecule expressed on a mammalian cell surface and a biotinylated cytokine ligand. The invention is not restricted in the range of target cell antigens which could be employed to mediate targeted gene delivery. In principle, any target cell antigen for which a specific secondary molecule is available or can be made available is eligible for application of the invention. It is recognized, however, that not every target cell-specific molecule might serve as an internalization site for viruses bound to it. Furthermore, the efficiency of gene delivery may depend on the composition of the molecular bridge between the virus and the target cell-specific molecule (Etienne-Julan et al., J. Gen. Virol. 73(1992):3251). Hence, attempts to target gene delivery vehicles to specific cell types relying on methods in which a specific target cell ligand is expressed on the surface of the virus particle, either as a wild-type molecule or as a hybrid with a heterologous protein, can be extremely costly and time-consuming since certain chosen approaches may be destined to fail. The procedures disclosed in this invention, however, allow for comprehensive screening of useful target molecules by employing many different secondary molecules added to the same gene delivery vehicle preparation. Therefore, application of the invention will tremendously increase the chances for successful targeted gene delivery and allow optimization of the procedures at relatively low costs. In addition, standardization and validation of the gene delivery preparations will be simplified as compared to strategies using antibody-antibody or antibody-ligand complexes or methods relying on direct chemical modification of the virus envelope or capsid.
[0050] The binding of the secondary molecules to the recombinant viruses is mediated by substances which are exposed on the virus surface and have specific binding capacity for the secondary molecules. Preferably, the substances bind to the secondary molecules with high affinity. The substances are selected from or contain regions from proteins including, but not restricted to, Protein A, Protein G, FcR, anti-immunoglobulin scFv, avidin, streptavidin, proteins containing structural peptide domains that can specifically interact with a peptide domain counterpart, and recombinant derivatives from the above. Their exposure on the surface of recombinant viruses is envisaged in several ways, which are listed below:
[0051] A. For Recombinant Viruses with an Envelope:
[0052] Recombinant retroviruses are described in the invention as the paradigm for recombinant enveloped viruses. The invention is, however, not restricted to retroviruses. The invention also applies to other enveloped viruses, such as e.g. rhabdoviruses or herpes viruses.
1. If the binding substance is itself a trans-membrane molecule, e.g. FcR, the complete wild-type binding substance can be expressed on the surface of the retrovirus producing cell line. Alternatively, retrovirus packaging constructs can be expressed in cells naturally expressing the binding substance. Whether these approaches will result in inclusion of the binding substance in the retrovirus particle depends, at least in part, on the nature of the substance. During the assembly of murine retroviruses at the cell surface, cellular membrane molecules are merely excluded from the virus particle, although exceptions have been observed (Závada, J. Gen. Virol. 63(1982):15; Calafat et al., J. Gen. Virol. 64(1983):1241). In addition, exclusion of the binding substance from the virus membrane may be overcome by expressing it at very high density on the membrane of the retrovirus producing cell line (Suomalainen and Garoff, J. Virol. 68(1994):4879). 2. In the application of method no. 1, it is preferred that the trans-membrane binding substance lacks sequences which might elicit intracellular processes in the retrovirus producing cell line or intraviral processes in the virus particle. Such could perhaps occur upon binding of the secondary targeting molecule. Therefore, the binding substance can also be a modified derivative of the wild-type molecule. Modifications include any mutation preventing signal processing through the binding substance. The use of such truncated binding substances is furthermore preferred as to prevent interactions with cellular proteins in the retrovirus producing cell line. It has been suggested that interactions with cytoplasmic proteins might be partially responsible for the exclusion of host cell surface proteins from retrovirus particles (Young et al., Science 250(1990):1421). 3. Since the fusion process between an infective retrovirus particle and a target cell is assumed to be mediated by an as yet undefined region in the carboxy terminal envelope peptide, it can be envisaged that target cell binding according to method no. 1 or 2 might be insufficient to obtain internalization of the gene delivery vehicle into the target cell. Therefore, it may be necessary to co-express the trans-membrane binding substances on the retrovirus surface with wild-type retroviral envelope molecules or segments thereof, which provide the retrovirus with fusion capability. Examples 2 and 3 describe the co-expression of hFcgRIa and wild-type retroviral envelope molecules on the surface of recombinant retrovirus producing cell lines and functional IgG Fc-binding by the exposed hFcgRIa molecules. It is preferred that the co-expressed envelope molecule is incapable of recognizing receptor molecules on cells present in the mixture of cells or in the living animal body subjected to the gene delivery preparation. This can be achieved by employing truncated envelope molecules lacking their receptor recognition site or wild-type envelope molecules from a retrovirus species with a tropism restricted to cells not present in the mixture of cells or in the living animal body subjected to the gene delivery preparation. 4. Hybrid molecules can be made containing (segments of) a binding substance and (segments of) a heterologous protein which anchors the hybrid molecule in the membrane of the retrovirus producing cell line. This method also applies to binding substances which are not themselves trans-membrane proteins. Molecules serving as a membrane anchor can be derived from natural trans-membrane proteins including but not restricted to cytokine or hormone receptors, cell adhesion or interaction molecules, complement receptors, and immunoglobulin receptors. Alternatively, the hybrid molecule could comprise a membrane attachment region from a glycosylphosphatidylinositol-anchored protein. The invention is not restricted to a defined junction site between the heterologous molecules. 5. In the application of method no. 4, it is preferred that the membrane anchor molecule lacks sequences which might elicit intracellular processes in the retrovirus producing cell line or intraviral processes in the virus particle, or interact with cellular proteins in the retrovirus producing cell line. It is, therefore, preferred that sequences conferring the above be deleted from the hybrid binding substance. 6. Because the retroviral envelope molecule is selectively incorporated in retroviral particles and is assumed to mediate fusion between the virus and the target cell, it is preferred over methods nos. 4 and 5 to construct hybrid molecules containing the retroviral envelope peptide sequences responsible for the above processes and the peptide sequences from the binding substance responsible for binding to the secondary target molecule. Also this method applies to binding substances which are not themselves trans-membrane proteins. The invention is not restricted to a defined junction site between the heterologous molecules. Example 4 describes the construction of two such hybrid binding substances and Example 5 shows that the hybrid binding substances retain functional binding capacity for secondary target molecules. 7. Hybrid molecules can be made containing (segments of) a binding substance and (segments of) a heterologous protein which specifically interacts with extracellular regions of membrane molecules on the retrovirus producing cell surface. Preferably, the hybrid molecule interacts with membrane molecules which are specifically incorporated into retrovirus particles. Typically, these membrane molecules are (segments of) retroviral envelope proteins. This method also applies to binding substances which are not themselves trans-membrane proteins. 8. The expression of viral membrane proteins on the cell surface requires correct folding and assembly in the endoplasmic reticulum (ER) of the virus producing cell line (reviewed by Doms et al., Virology 193(1993):545). Retroviral envelope molecules assemble into dimers, trimers, or tetramers, depending on the retrovirus species. Incorrect oligomerization may prevent proper transport to the Golgi apparatus, leading to degradation of the molecule. It can be anticipated that this would be the faith of some hybrid substances produced according to methods nos. 4 to 7. This could possibly be prevented by co-expressing the hybrid substance with wild-type envelope molecules or segments thereof. The formation of hetero-oligomers might ensure correct processing in the ER. The preferred requirements for co-expressed envelope molecules described under no. 3 also apply here.
[0061] The principles of methods A 1-8 also apply to pseudotyped viruses in which the envelope glycoproteins from one virus species are carried on the membrane of a heterologous virus species. Such phenotypic mixing of envelope glycoproteins occurs between a variety of different virus families (reviewed by Závada, J. gen. Virol. 63(1982):15). The invention also applies to enveloped viruses with hybrid envelope proteins, comprising fragments of related or even unrelated viruses. It has, e.g., been shown possible to generate infectious recombinant retroviruses carrying hybrid influenza hemaglutinin/retrovirus envelope proteins (Dong et al., J. Virol. 66(1992):7374).
[0062] B. For Viruses with a Capsid:
[0063] The invention is described for, but not restricted to, recombinant adenoviruses and adeno-associated viruses. Hybrid molecules can be made containing (segments of) a binding substance and (segments of) virus capsid proteins. For adenoviruses, it is preferred to locate the binding substance in the head domain of the fiber protein. This domain carries the receptor recognition site and it has been shown possible to change the adenovirus receptor specificity by manipulating this segment (Stevenson et al., J. Virol. 69(1995):2850). For certain hybrid molecules, it may be necessary to co-express the hybrid molecule with wild-type fiber protein to ensure proper fiber trimerization and association with the penton base complex. Alternatively, other capsid proteins of adenovirus may be used to incorporate the binding substance. E.g., Curiel et al. (Hum. Gene Ther. 3(1992):147) have generated a chimeric serotype 5 adenovirus that contains a Mycoplasma pneumoniae P1 protein epitope as part of the hexon protein.
[0064] It is furthermore preferred that the natural adenovirus receptor binding sequences be deleted from the hybrid molecule. Hybrid AAV capsid proteins with altered binding specificity are preferably made using (segments of) VP3, since the AAV capsid mainly comprises of this molecule. Alternatively, VP1 or VP2 could be used. The AAV viral proteins allow insertions which are exposed on the capsid surface (unpublished results from the group of Dr. R. Samulski, Univ. of North Carolina, Chapel Hill, N.C.). For certain hybrid molecules, it will be necessary to co-express the hybrid molecule with wild-type capsid protein. The invention is not restricted to specific junction sites between the heterologous proteins.
[0065] Since many virus capsids self-assemble independent of the presence of viral DNA, empty pseudocapsids can be generated in vitro. Assembly of empty AAV-like particles does not even require all three capsid proteins (Ruffing et al., J. Virol. 66(1992):6922). Thus, there is significant freedom to design novel pseudocapsids. Empty virus-like particles can be used to package and transfer exogenous non-viral DNA. This has been shown for Polyoma Virus pseudocapsids (Forstová et al., Hum. Gene Ther. 6(1995):297). Furthermore, exogenous non-viral DNA can be chemically coupled onto the exterior of virus capsids (Curiel et al., Hum. Gene Ther. 3(1992):147; Cotten et al., Proc. Natl. Acad. Sci. USA 89(1992):6099). The invention emphatically also applies to the latter two approaches and their combination, i.e., chemical coupling of exogenous DNA to the outer surface of empty capsids.
EXAMPLES
Example 1
[0000] Specific Binding of Biotinylated G-CSF to G-CSFR Molecules Expressed on the Surface of Mouse Fibroblasts.
[0066] To express receptors for granulocyte-colony stimulating factor (G-CSF) on the cell membrane of murine fibroblasts, PA317 cells (Miller and Buttimore, Mol. Cell. Biol. 6(1986):2895) were transduced with ecotropic LNCX/GRDcyt virus. The construct pLNCX/GRDcyt (generated in the laboratory of Dr. I. Touw, Erasmus University, Rotterdam, NL) was made by inserting the cDNA sequence for a mutant G-CSF receptor (DG-CSFR) into pLNCX (Miller and Rosman, BioTechniques 7(1989):980). DG-CSFR differs from the wild-type molecule by an almost complete deletion of the intracellular domain, rendering the receptor incapable of signal-transduction. The extracellular and trans-membrane domains of DG-CSFR are of wild-type structure. DG-CSFR exhibits, therefore, normal binding capacity for its cytokine ligand. Transduced PA317 cells were isolated by selecting for resistance to 1 mg/ml G418 (Geneticin; Gibco, Paisley, UK), conferred by expression of the neo r gene in LNCX/GRDcyt. Resistant PA317 cells were incubated with biotinylated G-CSF. Bound G-CSF was visualized on a Fluorescence Activated Cell Sorter (FACS) after incubation with PE-conjugated Streptavidin (Molecular Probes, Eugene, Oreg.), biotinylated goat-anti-Streptavidin antibodies (Vector Laboratories, Burlingame, Calif.), and a second incubation with PE-Streptavidin. As can be seen in FIG. 1 , untransduced PA317 cells did not bind any biotinylated G-CSF, whereas approximately 27% of the transduced cells bound G-CSF. After FACS sorting of positive cells and cloning by limiting dilution, a clone was isolated which strongly bound biotinylated G-CSF ( FIG. 1C ). This example shows that a biotinylated cytokine specifically binds to its natural receptor expressed on the membrane of a mammalian cell line.
Example 2
[0000] Generation of Recombinant Retrovirus Packaging Cell Lines Expressing hFcgRIa Proteins on Their Cell Membrane.
[0067] For expression of functional hFcgRIa on the surface of retrovirus packaging cell lines, the construct pRc/CMV-hFcgRIa was used. This construct was generated by inserting a 1.3 kb HindIII-NotI fragment including the full-length p135 hFcgRIa-cDNA sequence (Allen and Seed, Science 243(1989):378; GenBank accession number M21090) from clone CDM into the polylinker of pRc/CMV. Twenty microgram pRc/CMV-hFcgRIa was transfected onto the ecotropic packaging cell line GP+E-86 (Markowitz et al., J. Virol. 62(1988):1120) and onto the amphotropic packaging cell line PA317, according to the method described by Chen and Okayama (Mol. Cell. Biol. 7(1987):2745). Transfectants were selected for resistance to 1 mg/ml G418, conferred by expression of the SV40pr-neo r -p(A) cassette on the pRc/CMV-hFcgRIa construct. Pools of resistant cells were analyzed for hFcgRIa expression on a FACS, after staining with the anti-FcgRI monoclonal antibody (MoAb) 22 (Guyre et al., J. Immunol. 143 (1989):1650) and FITC-conjugated goat-anti-mouse IgG antibodies (GaM-FITC; Becton Dickinson Immunocytometry Systems, San Jose, Calif. [BDIS]). Table 1 shows that only few G418-resistant GP+E-86 cells (E86FcR) and G418-resistant PA317 cells (PAFcR) were found to express FcgRI on their surface. FcgRI-expressing cells were sorted using the FACS and expanded. After two weeks of culture, the sorted populations were analyzed for FcgRI-expression as before. As can be seen in Table 1, the sorting procedure resulted in significantly enriched FcgRI-expressing E86FcR and PAFcR cell populations.
TABLE 1 FcgRI Expression on pRc/CMV-hFcgRIa Transfected and FACS Sorted Ecotropic and Amphotropic Recombinant Retrovirus Packaging Cell Lines. FcRI Positive Average FcgRI Packaging Cells Cells (%) 1 Expression 2 GP + E-86 0.1 N.D. PA317 0.2 0.98 E86FcR 0.9 3 N.D. EB6FcR sorted 16.4 1.16 PAFcR 7.6 3 N.D. PAFcR sorted- 10.5 1.43 315 4 PAFcR sorted- 20.5 2.37 216 4 1 Percentage cells exhibiting FITC fluorescence following incubation with MoAb 22 and GaM-FITC. Controls incubated with GaM-FITC only were set to ≦0.1%. 2 Relative median FITC fluorescence after incubation with MoAb 22 and GaM-FITC as compared to incubation with irrelevant anti-KLH isotype control MoAb (BDIS) and GaM-FITC. 3 Average of two independent measurements. 4 PAFcR cells were subjected to two independent sorting experiments. N.D., not done.
[0068] To study whether hFcgRIa remained stably expressed on the packaging cell surface in the absence of g-chain coexpression, two sorted cell populations expressing different levels of hFcgRIa, as deduced from their median FITC-signals after staining with MoAb 22 as compared to staining with irrelevant isotype controls, were cultured for up to eight weeks in culture medium containing G418. Regular reanalysis showed rather stable median fluorescence signals (approx. 1.5 and 2.3 for the two sorted populations, as compared to 1.0 for untransfected PA317 cells; FIG. 2 ) throughout the observation period.
[0069] Immunophenotypic analysis of wild-type hFcgRIa revealed three distinct epitopes, one of which comprises the Fc-binding domain (Guyre et al., J. Immunol. 143(1989):1650). One of the sorted cell populations was analyzed using the directly FITC-stained MoAbs 22 and 32.2 (Medarex, Annandale, N.J.), which each define one of the two non-Fc-binding epitopes. Table 2 shows that both MoAbs recognized the hFcgRIa molecule exposed on the cell surface. The increase in fluorescence which was observed when both MoAbs were combined demonstrate that they bind to distinct epitopes on the packaging cell surface. Pre-incubation of the cells with irrelevant unstained mouse immunoglobulins of IgG1 or IgG2a isotype (BDIS) did not influence the binding of MoAbs 22 and 32.2 (not shown). These results demonstrate that hFcgRIa of correct immunophenotypic structure was expressed on the cell surface of a retrovirus packaging cell line.
TABLE 2 Immunophenotype Analysis of Amphotropic Packaging Cells Expressing hFcgRIa. % Positive Mean Fluorescence FITC-labeled MoAb Cells Intensity (a.u.) anti-KLH (irrelevant) 0.9 1 15.0 anti-hFcgRIa MoAb 22 13.0 64.6 anti-hFcgRIa MoAb 8.1 46.3 32.2 anti-hFcgRIa MoAbs 22 + 32.2 21.1 105.8 PAFcR sorted-216 cells were incubated with the indicated FITC-labeled MoAbs and analyzed on a FACS. 1 The threshold for a positive score was set at ≧99% negative cells on the anti-KLH-FITC stained sample.
[0070] Ecotropic and amphotropic hFcgRIa-expressing populations were cloned by limiting dilution. Twelve individual E86FcR and eleven individual PAFcR clones were expanded and analyzed for hFcgRIa-expression. The two clones expressing the highest level of hFcgRIa from each population were used to investigate whether hFcgRIa-expression on the cell surface of packaging cells influences the retrovirus production. To this end, cell-free supernatant was harvested from these four clones, as well as from the parental packaging cell lines under standard conditions (72 h at 32° C. in 10 ml alpha-modified DMEM with 10% BCS per 80 cm 2 confluent cell monolayer). The supernatants were analyzed for reverse transcriptase activity (Goff et al., J. Virol. 38(1981):339), in a two-fold dilution titration. Comparison of the radiation intensity of incorporated 32 P-dTTPs by exposure to X-ray film revealed that expression of hFcgRIa did not influence the shedding of virus particles into the culture medium more than a factor 2.3 (Table 3).
TABLE 3 Retrovirus Particle Production by Packaging Cell Lines Expressing hFcgRIa. Packaging Cell Retrovirus Line FcgRI Expression 1 Production 2 PA317 1.2 (1) PAFcR-2 2.3 2.0 PAFcR-8 2.7 2.0 GP + E-86 not done 1.8 E86FcR-3 2.8 0.8 E86FcR-14 2.6 1.3 1 Relative median fluorescence signal after staining with FITC-labeled MoAbs 22 + 32.2 as compared to anti-KLH-FITC. 2 The RT-activity in the culture supernatant is given relative to the RT-activity shed by PA317 cells.
Example 3
[0000] Immunoglobulin Binding by hFcgRIa Proteins Expressed on the Cell Membrane of Recombinant Retrovirus Packaging Cell Lines.
[0071] To test whether hFcgRIa expressed on the surface of retrovirus packaging cells is capable of specific immunoglobulin-Fc binding, PAFcR sorted-315 cells were incubated with irrelevant mouse immunoglobulins of IgG1 or IgG2a isotype. FcgRI molecules should bind IgG2a molecules with high affinity and IgG1 molecules with low affinity. As can be seen in table 4, approximately one third of the sorted cells were expressing low amounts of hFcgRIa, as indicated by MoAb22-staining with low relative median signal. All hFcgRIa molecules on PAFcR cells also bound mouse IgG2a (similar percentage positive cells and signal intensity), whereas mouse IgG1 was hardly bound. On human primary monocytes, which were used as a positive control, hFcgRIa molecules were strongly expressed and specifically bound mouse IgG2a immunoglobulins. The capacity of hFcgRIa molecules on monocytes to bind immunoglobulins, however, was lower than measured on pRc/CMV-hFcgRIa transfected packaging cells (55% of MoAb22-positive monocytes bound IgG2a, with a much lower signal intensity). In conclusion, all hFcgRIa molecules characterized by MoAb22-binding expressed on the surface of PAFcR cells exhibit a correct structure for specific high affinity binding of immunoglobulins.
TABLE 4 Immunoglobulin-Fc Binding by FcgRI Expressed on PA317 Cells. PAFcR sorted- Human Monocytes PA317 315 Primary Rel. Rel. Rel. MoAb % Pos. Med 1 % Pos. Med. % Pos. Med. none 0.8 (1) 0.9 (1) 0.8 (1) irr-IgG1 0.7 1.84 0.6 0.96 6.2 1.15 irr-IgG2a 35.1 3.69 0.4 0.95 30.6 1.61 MOAb22 64.2 8.82 0.5 0.94 33.0 1.65 Human primary monocytes, PA317 cells, or a pool of pRc/CMVhFcgRIa transfected PA317 cells partially expressing hFcgRIa (PAFcR sorted-315) were first incubated with MoAb22 (IgG1 isotype), anti-KLH IgG1, anti-KLH IgG2a, or PBS/1% BSA (“none”), followed by an incubation with GaM-FITC. The percentage of positive cells and the median fluorescence intensities were determined on a FACS. 1 Relative median fluorescence intensity of cells incubated with indicated primary MoAb and GaM-FITC as compared to cells incubated with GaM-FITC alone.
Example 4
[0000] Construction of Hybrid hFcgRIa/Mo-MuLV Envelope Genes.
[0072] For the construction of hybrid molecules with immunoglobulin-binding properties of hFcgRIa and virus-incorporation and membrane-fusion properties of envelope glycoprotein, pRc/CMV-hFcgRIa (see above) was used in combination with Mo-MuLV env sequences (Shinnick et al., Nature 293(1981):543). Two different hybrid hFcgRIa/Mo-MuLV-env constructs were made ( FIG. 3 ). In both constructs, 3′ hFcgRIa sequences in the pRc/CMV-hFcgRIa construct were replaced by 3′ MO-MuLV env sequences. Both constructs contain p135 sequences from the leader sequence to the HinP1I-site at position 849-852. This fragment comprises the three extracellular domains of hFcgRIa, excluding the 61 carboxy terminal nucleotides. In hybrid construct pRc/CMVFcRenv-15, the p135-fragment is coupled to p15E env sequences encoded by a fragment starting from the HpaI-site at position 7195-7200 of Mo-MuLV until position 7823 in the IR sequence of the 3′LTR. To this end, the HpaI-site was converted into a HinP1I-site by PCR, and a NotI-site was introduced in the 3′LTR by PCR. An internal SpeI-PvuII fragment (nt 7487-7747) was exchanged for cloned sequences. The correct sequence of the hFcgRIa/Mo-MuLV-env junction and of all sequences generated by PCR was confirmed by sequencing. Hybrid gene FcRenv-15 encodes an in-frame fusion protein comprising the extracellular domains of hFcgRIa until an Arg-residue 12 amino acids downstream from the 3′ Cys-residue forming the third immunoglobulin-like extracellular loop and all but the five most 5′ p15E amino acids. To generate hybrid construct pRc/CMV-FcRenv-70, the HinP1I-site from the 5′ p135-fragment was made blunt-end and was ligated to a BamHI (position 6537-6542)-PvuII (position 7745-7750) fragment of Mo-MuLV, after the BamHI-site was made blunt-end, and the 3′ PvuII-NotI PCR-fragment from pRc/CMV-FcRenv-15. Ligation of the blunt-end HinP1I and BamHI-sites restored the BamHI-site. The correct structure of the hFcgRIa/Mo-MuLV-env junction was confirmed by sequencing. Hybrid gene FcRenv-70 comprises the same hFcgRIa-fragment as described for pRc/CMV-FcRenv- 15 coupled to the Mo-MuLV env sequences starting from an Ile-residue at the BamHI-site in the amino terminal domain of gp70 and including the complete proline-rich hinge-like region and carboxy terminal domain of gp70 and the complete p15E peptide.
[0073] On Jul. 24, 1996, the applicants deposited with the European Collection of Cell Cultures (ECACC), Salisbury, Wiltshire, U.K., the plasmid pRc/CMV-FcRenv-15, given ECACC accession number P96072515, and plasmid pRc/CMV-FcRenv-70, given ECACC accession number P96072514. These deposits were made under the provisions of the Budapest Treaty on the International Recognition of the Deposit of Microorganisms for the purposes of patent procedure and the regulations thereunder.
Example 5
[0000] Hybrid hFcgRIa/Mo-MuLV Envelope Genes FcRenv-15 and FcRenv-70 Encode Proteins of Correct Molecular Weight that have Immunoglobulin Binding Capacity.
[0074] To test whether the fusion genes FcRenv-15 and FcRenv-70 encode functional hybrid molecules with immunoglobulin binding properties, the pRc/CMV-FcRenv-15 and pRc/CMV-FcRenv-70 constructs (Example 4) were used as templates for coupled in vitro transcription and translation. Transcription was initiated at the T7 promoter upstream of the gene insertion in the pRc/CpC vector. One microgram pRc/CMV-FcRenv- 15 or pRc/CMV-FcRenv-70 DNA was added to a 25 microliter leucine-free T7 TnT coupled reticulocyte lysate reaction mixture (Promega, Madison, Wis.) with 20 units RNasin ribonuclease inhibitor (Promega) and 20 microCi 3 H-leucine (Amersham, Buckinghamshire, UK). The reaction was allowed to proceed for 120 minutes at 30° according to the guidelines provided by the manufacturer. Control reactions were performed without DNA template, with an irrelevant control DNA template (firefly luciferase control DNA provided with the T7 TnT coupled reticulocyte lysate system), and with positive control pRc/CMV-hFcgRIa encoding wild-type hFcgRIa. To 5 microliter of the reaction mixture, 20 microliter SDS-PAGE loading buffer (to a final concentration of 62.5 mM Tris pH 6.8, 10% glycerol, 2% beta-mercaptoethanol, 0.5% SDS, 0.0025% bromo phenol blue) was added. The remaining 20 microliter was diluted with 180 microliters of precipitation buffer (10 mM Tris-HC1 pH 7.5, 150 mM NaCl, 5 mM EDTA, 1% Triton-100 with protease inhibitors PMSF at 0.1 mM, aprotinin at 10 microgram/ml, pepstatin at 5 microgram/ml, trypsin inhibitor at 10 microgram/ml, and leupeptin at 10 microgram/ml). Next, 10 microliter KLH-aKLH-IgG2a-Sepharose slurry was added and mixed by tilted rotation for 90 minutes at room temperature. The slurry was prepared according to the following procedure. First, 16.4 mg Keyhole Limpet Hemocyanin (KLH; Sigma, St. Louis, Mo.) was coupled at 1.8 mg/ml to 1 gram CNBr-activated Sepharose 4B (Pharmacia Biotech, Uppsala, SE) according to the manufacturers' instructions. The KLH-Sepharose product was stored in PBS with 0.002% sodium azide at 4° C. Next, KLH-Sepharose was mixed 1:1 with 50 microgram/ml anti-KLH-IgG2a monoclonal antibody (Beckton-Dickinson Immunocytometry Systems, San Jose, Calif.) and incubated for 30 minutes at room temperature. Finally, the KLH-aKLH-IgG2a-Sepharose beads were washed two times in 20 volumes PBS. This procedure should result in Sepharose beads coated with immunoglobulins of the IgG2a isotype that have their Fc domain projecting outwards. After incubation of the in vitro transcribed and translated reaction product with KLH-aKLH-IgG2a-Sepharose, the KLH-aKLH-IgG2a-Sepharose beads were spun down and the precipitation supernatant was removed. To 5 microliter precipitation supernatant 20 microliter SDS-PAGE loading buffer was added as above. The pelleted KLH-aKLH-IgG2a-Sepharose beads were washed 6-times in 1 ml precipitation buffer. After a final spin, 25 microliter SDS-PAGE loading buffer was added to the pellet. The above described procedure resulted in three different samples of each coupled in vitro transcription-translation reaction, i.e., the total reaction product, the immunoglobulin bound precipitated product, and the remaining material in the precipitation supernatant. Ten microliters of these samples were heated at 85° C. for 2 minutes and subsequently separated by SDS-PAGE through a 10% gel according to standard procedures (Laemmli, Nature 227(1970):680). After separation, the proteins in the gel were fixed in water/isopropanol/acetic acid (65%/25%/10% vol.) for 30 minutes at room temperature and thereafter incubated for 15 minutes at room temperature in AMPLIFY (Amersham) for fluorographic enhancement of the signal. Finally, the gel was dried for 90 minutes at 80° C. under vacuum and exposed to X-ray film with an enhancing screen. FIG. 5 shows the result of this experiment. As can be seen, the constructs with genes encoding wild-type hFcgRIa or hFcgRIa/Mo-MuLV envelope fusion molecules all expressed proteins exhibiting a migration pattern corresponding to their predicted molecular weights, i.e., 42.5 kD for hFcgRIa, 52 kD for FcRenv-15, and 75.6 kD for FcRenv-70. The latter gene furthermore encodes a smaller protein product. This molecule perhaps represents the approximately 60 kD proteolytically processed protein after release of the p15E peptide. As can furthermore be seen in FIG. 5 , all these protein products were precipitated by KLH-aKLH-IgG2a-Sepharose beads, in contrast to the irrelevant control protein luciferase, demonstrating that the immunoglobulin binding property of wild-type hFcgRIa is retained after fusion of the three extracellular domains of hFcgRIa to Mo-MuLV envelope sequences. | A method for producing viral gene delivery vehicles which can be transferred to pre-selected cell types by using targeting conjugates. The gene delivery vehicles comprise: 1) the gene of interest; and 2) a viral capsid or envelope carrying a member of a specific binding pair, the counterpart of which is not directly associated with the surface of the target cell. These vehicles can be rendered unable to bind to their natural cell receptor. The targeting conjugates include the counterpart member of the specific binding pair, linked to a targeting moiety which is a cell-type specific ligand (or fragments thereof). The number of the specific binding pair present on the viral vehicles can be, for example, an immunoglobulin binding moiety (e.g., capable of binding to a Fc fragment, protein A, protein G, FcR or an anti-Ig antibody), or biotin, avidin or streptavidin. The virus' outer membrane or capsid may contain a substance which mediates entrance of the gene delivery vehicle into the target cell. Due to the specificity of the ligand, the binding pair's high affinity, and the gene delivery vehicle's inability to be targeted when used alone, the universality of the method for gene delivery, together with its high cell type selectively can be achieved by using various targeting conjugates. | 0 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a Divisional of U.S. Ser. No. 11/774,707, filed Jul. 9, 2007, entitled IMPROVED METHOD AND APPARATUS FOR USING FOAM PANELS AS FORMS FOR MAKING CONCRETE WALLS, and is incorporated by reference herein in its entirety.
FIELD OF TECHNOLOGY
[0002] The present invention relates generally to ties for concrete wall forming systems of a type using foam panels; and more particularly to a special tie utilized to secure adjacent panel sections together.
BACKGROUND
[0003] While wall forming systems have been in use for many years, the last two decades has seen considerable development in this industry in the use of expanded polystyrene panels as forms for poured concrete walls. After the concrete has hardened, the panels may be left in place on the walls to serve as permanent insulation, or they may be stripped off to reveal the exposed concrete.
[0004] Upon introduction of this new wall forming system, it was found that it was unnecessary to use small “building blocks” to create the form panels to build a form system for receiving poured concrete. Rather, larger and larger panels are now being utilized to create the concrete forms. Developments in this field include U.S. Pat. Nos. 4,765,109 and 4,916,879 to Boeshart, which show how to make right angle corners and “T” intersections, which patents are incorporated herein by reference in their entirety.
[0005] Adjacent sections of foam panels have pre-formed mating tongue and groove connections that hold them together on the main portions of the foam panel sections. But sometimes these tongue and groove portions need to be trimmed off to make a foam panel form that is shorter than the length of a standard foam panel length. When this occurs it is necessary to find another way to hold adjacent foam panels together during the time that the concrete is being poured and cured. Solving this problem in the industry has been difficult and labor intensive, with many proposed solutions being not sufficiently reliable. Accordingly there remains a need for solving this difficult problem.
SUMMARY
[0006] The present invention relates to a foam panel concrete form using concrete reinforcement rods which extend on each side of a joint in the foam panel concrete form and into complementary shaped openings in ties which hold two adjacent panels in a spaced and parallel relationship. The concrete reinforcement rod can slide into the openings in adjacent ties with little resistance in a first rotary position of the concrete reinforcement rod. When the concrete reinforcement rod is rotated to a second rotational position within the openings, the reinforcement rod is in a tight frictional fit in the openings for helping to hold adjacent ties and the adjacent foam panels in a fixed relationship with respect to each other during a time when concrete is poured between the foam panels, thereby also serving to re-enforce the concrete after the concrete has cured.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 is a perspective view of a preferred embodiment of the present invention providing a concrete form constructed of foam panels;
[0008] FIG. 2 is a perspective view of the preferred embodiment of FIG. 1 of the present invention showing ties formed in the foam panels to hold adjacent foam panels in a spaced parallel relationship and concrete reinforcement rods placed on and in the ties to hold the form sections together and to reinforce the concrete after it has cured, with some reinforcement rods being shown in dashed lines to indicate where they can be placed;
[0009] FIG. 3 is a top view of the structure shown in FIG. 2 ;
[0010] FIG. 4 is a side view of that portion of a tie in FIG. 3 that is exposed between the two foam panels;
[0011] FIG. 5 is a side elevational view of the foam panel structure shown in FIG. 4 , but showing the foam panels in dashed lines and the ties in solid lines;
[0012] FIG. 6 is a side elevational view of one of the corner tie structures shown in the lower right portion of FIG. 7 ;
[0013] FIG. 7 is a top plan view of one of the corner structures of the present invention;
[0014] FIG. 8 is a side elevational view of one of the sections of a tie used in the lower left and upper right portion of FIG. 7 ;
[0015] FIG. 9 is a perspective view showing how a fastener is used to connect the structure of FIG. 8 to the structure of FIGS. 10 and 11 ;
[0016] FIG. 10 is a side elevational view of one of the sections of a tie used in the lower left and upper right portion of FIG. 7 ;
[0017] FIG. 11 is a side elevational view of one of the sections of a tie used in the lower left and upper right portion of FIG. 7 , this section just being longer than the one shown in FIG. 10 , but otherwise identical;
[0018] FIG. 12 is a perspective view of the preferred embodiment of FIG. 1 of the present invention showing ties formed in the foam panels to hold adjacent foam panels in a spaced parallel relationship and concrete reinforcement rods placed on and one tie only being illustrated to hold the form sections together and to reinforce the concrete after it has cured, it being understood that other reinforcement rods would be placed in the other aligned holes shown that are of a similar shape;
[0019] FIG. 13 is a perspective view showing how a reinforcement rod is in position to be inserted into an opening in one of the ties;
[0020] FIG. 14 is a perspective view like FIG. 13 but showing how a reinforcement rod has been inserted into an opening in one of the ties in the direction of an arrow;
[0021] FIG. 15 is a perspective view like FIG. 14 but showing how a reinforcement rod has been rotated in the direction of an arrow in the opening in one of the ties to frictionally lock the reinforcement rod against the sliding movement along the line of the arrow in FIG. 14 ;
[0022] FIG. 16 is a perspective view of adjoining foam panels showing the tongue and groove relationship used to lock adjacent panels together by moving them relatively up or down as shown by the arrow in FIG. 16 ;
[0023] FIG. 17 is a perspective view of abutting foam panel forms wherein the tongue and groove portions are not present, for example because one of the forms needs to be shorter than a standard length of form, and also showing the use of a glue gun to seal the abutting edges together as well as reinforcement rods which are installed after the abutting edges are glued together;
[0024] FIG. 18 is a top view of a T-joint of the present invention where one concrete wall to be formed will join with another concrete wall;
[0025] FIG. 19 is a perspective view of a top portion of the structure of FIG. 18 ;
[0026] FIG. 20 is a top view of a corner section of the present invention where one concrete wall to be formed will join with another concrete wall;
[0027] FIG. 21 is a perspective view of the corner section of FIG. 20 , portions of which are also shown in FIGS. 6-11 ;
[0028] FIG. 22 is a perspective view showing how the ties can be held together for shipping purposes in a very compact fashion;
[0029] FIG. 23 is a perspective view of a foam panel concrete form which has been pre-assembled and showing in dashed lines places where “jack-o-lantern” type holes can be cut the foam wall to insert reinforcement rods there through;
[0030] FIG. 24 is a perspective view of a foam panel showing “jack-o-lantern lid” shaped holes being cut in the foam wall to insert reinforcement rods there through; and
[0031] FIG. 25 is a perspective view of a foam panel showing how a piece of “jack-o-lantern lid” shaped piece of foam is reinserted in the one of the holes after the insert reinforcement rods have been installed, and showing how the a piece of “jack-o-lantern lid” shaped piece of foam is pinned with nails or the like to hold it in place while concrete is being poured into the form.
DETAILED DESCRIPTION OF THE INVENTION
[0032] Referring now to the drawings wherein like reference numerals designate identical or corresponding parts throughout the several views, FIG. 1 shows a perspective view of a preferred embodiment 10 of the present invention. Foam panels 22 have a tongue portion 22 t on one edge and a groove portion 22 g on the other edge thereof for mating with one another. The top of each panel 22 has a projection portion 22 p . FIG. 12 shows the bottom of the structure of FIG. 2 and shows recessed portion 22 r of panels 22 and FIG. 16 shows how the tongue portion 22 t fits into the groove portion 22 g of adjacent panels 22 .
[0033] FIG. 5 is an end view for example, from the front of FIG. 2 , but showing the foam panels 22 in dashed lines and ties 11 in solid lines. These ties 11 are made of a solid plastic material which are preferably made of the same material as the ties in the two patents referred to above which are incorporated herein by reference. Each side of the tie 11 has a portion 12 which is molded inside of the panel 22 , but of course could be the type that slips down into a groove in panels 22 if desired. Portions 13 have an opening 16 thereof which can be seen in greater detail in FIGS. 13-15 , which will be discussed later. A portion 14 of the tie 11 extends between the portions 13 and has a plurality of extension tabs 14 t thereon to allow an ultimate user to put a reinforcement rod 21 between adjacent tabs 14 t , for example as shown in the right-most reinforcement rod 21 shown in solid lines in FIG. 2 . This allows the concrete to be formed between the foam walls 22 and when it cures the reinforcement rod 21 will be in a proper position to hold the concrete even if it cracks.
[0034] Hinge portions 19 allow the concrete forms to pivot to a position wherein the portions 14 and 13 of the tie will be more or less parallel to the interior walls of the foam panels 22 . When the form is desired to be used on the job site, it can be folded out to the position shown in FIGS. 2 , 3 and 12 , for example.
[0035] Referring now to FIG. 7 , it is noted that a corner portion is shown. In this top view, portions 112 of the corner structure are virtually identical to the portions 12 of the ties 11 of FIG. 5 . Essentially, the center section 14 , including tabs 14 t , have been cut off to make the structure shown in FIGS. 6 and 7 . Additionally, a fastener 121 is used and is shown in detail in FIG. 9 . This fastener 121 has tabs 121 t and 121 b thereon which fit into the opening 116 and through the top part 116 t of opening 116 and through the bottom 116 b of opening 116 . Once the portion 121 a , 121 b and 121 c extend through portions 113 , then the handle portion 121 h of the fastener 121 is turned so that the tabs 121 b and 121 t are not aligned with the portion of the opening 116 b and 116 t to thereby lock the portions 113 together as shown in FIG. 7 . FIG. 6 also shows the structure at the lower right portion of FIG. 7 before it has been bent into the position shown in FIG. 7 .
[0036] The other braced portion in the corner of FIG. 7 uses portions 112 , 113 , hinge 119 , etc., similar to that shown in FIGS. 8 and 9 , but instead of locking the portions 113 together, a “bow tie” shaped portion 211 is used as shown in FIGS. 10 and 7 . This bow tie 211 has openings 216 therein with a top portion 216 t and a bottom portion 216 b so that the fastener 121 shown in FIG. 9 can be used in the same way to first extend it through opening 116 of the tabs 113 and also through the openings 216 in bow tie 211 to secure the bow tie 211 in place as shown in FIG. 7 . FIG. 11 merely shows a longer bow tie 311 with end sections 313 and openings 316 .
[0037] Referring now to FIGS. 2 and 12 which show the top and bottom, respectively, of a form comprised of two foam panels 22 being held in spaced relationship by a plurality of ties 11 which are formed therein and extend between the two forms 22 , it is important to note that sometimes these forms 10 need to be trimmed to be shorter than the standard length because the concrete wall needs to be shorter than a multiple of the length of such standard forms 10 . When this occurs, the tongue portion 22 t and groove portion 22 g , for example as shown in FIGS. 12 and 16 , are trimmed off so that they are like shown in FIG. 17 . A glue gun with hot glue is applied to these planar edges as shown in FIG. 17 and the adjacent flat edges of foam panels 22 are glued together as indicated by the arrow shown in FIG. 17 . Once that has been done, there needs to be something more than merely glue to hold this joint when concrete is introduced. Simply stated, the glue is not always sufficient to prevent the joint from coming apart when the heavy concrete and the pressure exerted on the walls 22 occurs due to the pouring of the concrete. Consequently, once the adhesive or glued joint is formed, then the reinforcement rod 21 is inserted in the step-by-step fashion shown in FIGS. 13-15 .
[0038] Looking at FIG. 13 for example, the reinforcement rod 21 in the orientation shown, can be slid through the opening 16 in the direction of the arrow. It is noted that when this is done, the top portion 21 t of the reinforcement rod 21 extends through the top portion 16 t of the opening 16 in portion 13 of the tie 11 . Similarly, the lower portion 21 b of the reinforcement rod 21 extends through the lower portion 16 b of the opening 16 . It will be appreciated that the rod can easily pass into and through the opening 16 in this fashion as shown sequentially from FIG. 13 to FIG. 14 in the direction of the arrow. After the reinforcement rod 21 has been passed through all of the openings at the joint shown in FIG. 17 with the joint glued together, then the reinforcement rod 21 is rotated 90° as shown in FIG. 15 . This would typically be done by grasping the reinforcement rod 21 with pliers or a vice grip type of tool because there is a considerable amount of friction involved in rotating the tie 21 . Once the tie 21 is so rotated to the position shown in FIG. 15 , this will hold the joint 17 together where it has been glued. In fact, it may not be necessary to apply the adhesive between the joint. For each of the openings 16 in the ties, for example as shown in FIGS. 2 , 12 and 17 , a tie 21 will be inserted in the manner shown sequentially in FIGS. 13-15 . While it may not be necessary that every one of these openings 16 has a tie 21 therein, the more ties that are installed, the stronger the joint will be.
[0039] Referring now to FIGS. 18 and 19 , a form is shown in a configuration to pour one wall which is perpendicular to and joined with another wall. A bracing structure comprised of inner-connected elements 401 , 402 , 403 , 404 , 405 , 406 , 407 , 408 , 409 , 410 and 411 hold one course or level of foam of concrete foam walls 22 together so that additional courses of such elements can be placed above those that are shown in FIGS. 18 and 19 to form a taller concrete form. Of course this can be done as many times as necessary to form a concrete form as tall as desired.
[0040] More importantly to the invention at hand, it is noted that the ties 11 are in place so that a reinforcement rod 21 can be utilized to further hold the joint of the form together by extending the tie 21 through openings 16 sequentially as shown in FIGS. 13-15 . It is also noted that FIGS. 18 and 19 show an additional tie 21 which extends between two adjacent tabs 14 t and 90° to the reinforcement rod 21 which has previously been installed as noted above. This additional reinforcement rod 21 will further hold the concrete joint together after the concrete has cured. More reinforcement rods 21 can be used between the tabs 14 t , and of course, none of these reinforcement rods actually need to be bent down on the end like the ones shown in FIG. 19 .
[0041] Referring now to FIGS. 20 and 21 , it is noted that a corner section like FIG. 7 is shown with a structure 600 thereon which is similar to the devices shown in U.S. Pat. Nos. 4,765,109 and 4,916,879 to Boeshart, which show how to make right angle corners and which patents are incorporated herein by reference in their entirety. Portions 601 and 602 slip over the extreme outside of the corner and are connected together by braces 603 , 604 and 605 . Brace 603 extends to member 606 and 607 via members 608 and 609 .
[0042] Member 610 is attached at one end to member 603 and at the other end to member 611 . Member 612 connects members 610 and 613 together. Similarly, member 620 is attached at one end to member 603 and at the other end to member 621 . Member 622 connects members 620 and 623 together.
[0043] Member 630 is attached at one end to member 631 and at the other end to member 635 . Member 632 connects members 631 and 633 together. And on the other side, similarly, Member 630 is attached at one end to member 631 and at the other end to member 645 . Member 642 connects members 641 and 643 together. Member 646 connects member 641 to member 603 and member 647 connects member 631 to member 603 . This structure 600 allows for one course of foam panels 22 to be held in place at a corner and further allows an additional course to be added to the top of the structure 600 shown in FIGS. 20 and 21 , and held in place by overlapping members 601 , 602 , 606 , 607 , 612 , 613 , 621 , 623 , 631 , 633 , 641 and 643 .
[0044] Referring now to FIG. 22 , it is noted that a wooden dowel 421 can be utilized to extend through a plurality of ties 11 for the purpose of holding them together for shipping purposes. This dowel 421 is essentially the same or slightly less of a diameter as the opening 16 . A hard rubber locking block 450 is frictionally held on the end of the dowel 421 for holding the end of the dowel 421 . A hole in the rubber locking block 450 has a diameter than is slightly smaller than the diameter of the dowel, so that rubber locking block 450 can be pushed onto the end of the dowel 421 in the FIG. 22 configuration to hold all of the ties 11 together for shipping purposes.
[0045] Referring now to FIGS. 23-25 , it is noted that forms 500 and 501 are essentially identical except that it is necessary, due to the specifications of the wall that the form 501 be shorter in length than the form 500 . When this is necessary, it needs to be trimmed off, for example as shown in FIG. 17 on the abutting edges at the joint 502 . In FIG. 17 , as the courses are added one on top of another, it is very easy to reach over the top and insert the reinforcement rods 21 into the opening 16 sequentially as shown in FIGS. 13-15 . When the concrete form made of foam 500 and 501 are already formed having several courses high, then it becomes necessary to insert the reinforcement rod 21 in a different fashion. One such desired way to insert these rods is to cut an opening 503 as shown in dashed lines in FIG. 23 . This is done in the manner shown in FIG. 24 and it is cut with a saw 504 , for example in the manner that someone would cut a top out of a pumpkin when making a jack-o-lantern so that the inside of the opening 503 i is larger than the portion of the opening 503 o outside. By cutting the opening in this fashion, the plug 505 will be wedged back into the opening 503 when the concrete is poured and this will prevent it from popping out of the opening 503 if the hole 503 had straight walls instead of tapered walls.
[0046] Once the opening 503 has been cut and the plug 505 pushed inside the wall, a person would reach through the opening 503 and insert a concrete reinforcement rod 21 through the openings 16 in the exact same manner as shown sequentially in FIGS. 13-15 . It can be seen that this can be done at different levels as shown in FIG. 23 . After the concrete reinforcement rod 21 has been installed, then the plug 505 is pulled back and reinserted into the opening 503 and nails 506 are used to hold the plug 505 in place. Of course when the concrete is poured between the walls of forms 500 and 501 , the force of the poured plastic or liquid concrete pushes outwardly on the foam walls of the forms 500 and 501 . The plug 505 will be wedged against the inside of the opening 503 and will remain in place in the position shown in FIG. 25 .
[0047] Obviously many modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically described. | A foam panel concrete form is provided for using concrete reinforcement rods which extend on each side of a joint in the foam panel concrete form and into complementary shaped openings in ties which hold two adjacent panels in a spaced and parallel relationship. The concrete reinforcement rod can pass into the openings in adjacent ties with little resistance in a first rotary position of the concrete reinforcement rod. When the concrete reinforcement rod is rotated to a second rotational position within the openings the reinforcement rod is in a tight frictional fit in the openings for helping to hold adjacent ties and the adjacent foam panels in a fixed relationship with respect to each other during a time when concrete is poured between the foam panels, thereby also serving to re-enforce the concrete after the concrete has cured. | 4 |
BACKGROUND OF THE INVENTION
[0001] The present invention relates to the cleaning of shaker screens often used in petroleum extraction and mining operations, particularly to a device for the automatic cleaning of said shaker screens that allows the screens to be cleaned more efficiently and safely than with current “manual” cleaning methods.
[0002] Large screens known in the petroleum and mining businesses as shaker screens are used to filter out rocks and debris that accumulate during drilling or mining. In order for the screens to keep filtering properly, the screens must be cleaned to remove the accumulated debris. That cleaning is usually done manually, in present petroleum and mining operations, by personnel who manually use high-pressure hoses to wash the debris off of the screens. Alternatively, the shaker screens can be removed from the drilling or mining apparatus and cleaned in a separate device that is essentially a large dishwasher. The present invention is an improvement over both manual cleaning and the “dishwasher” type of screen cleaners, in that it enables automatic cleaning of the shaker screens, while active drilling or mining operations are going on, and that is both safer and more efficient. Further improvements of the present invention over manual cleaning are that it uses less fluid pressure on the screens, resulting in less damage to the shaker screens, that the present invention's downward spray system reduces the spray of potentially hazardous cleaning fluids, and does not require a worker to leave his or her current job task in order to clean the screens.
SUMMARY OF THE INVENTION
[0003] The automatic shaker screen cleaner of this invention is designed to complete the task of cleaning screens, such as on an oil rig shaker or in a mining operation, while active extraction operations are going on. In a preferred embodiment, the operator can use preset functions to set the on and “off” time of the unit as well as how many cleaning passes the spray transport will complete during the on time; when the unit is “on”, the electric motor powers all of the systems and the spray transport moves the spray nozzle bar back and forth along the shaker screens, cleaning the drilling debris from the screens based on the timing functions preset by the operators, and the unit will continue to run automatically throughout the drilling process, turning on and off based on operator set up, cleaning the screens without the need for human intervention.
[0004] A principal objective of this invention is enabling automatic cleaning of shaker screens while oil drilling or mining extraction are in progress, so that the screens do not to be cleaned manually (which requires extra worker time and can be less safe for workers than automatic cleaning) and the extraction process does not need to be halted for screen removal and cleaning.
[0005] Another objective of this invention is to minimize damage to the screens when cleaning. A further objective is to reduce the spray of potentially hazardous cleaning fluids and to minimize waste of cleaning fluids.
[0006] These and other advantages of this invention appear in the following detailed description and the accompanying drawings of the preferred embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1A is an overview of the main enclosure showing all the major systems and parts from a top view. FIG. 1B is an overview of the main enclosure showing all the major systems and parts from a side view.
[0008] FIGS. 2A , 2 B, 2 C, and 2 D are diagrams showing the standard sprayer transport, support beam, and universal mounting bracket.
[0009] FIGS. 3A , 3 B, 3 C, and 3 D are diagrams showing the low profile sprayer transport, support beam, and universal mounting bracket.
[0010] FIG. 4 is a diagram showing the main enclosure with hoses attached to the remote sprayer transport, which is in turn mounted on a test tank, simulating a shaker screen in the manufacturing environment
[0011] FIG. 5 is a diagram showing a top view of the components inside the main enclosure.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0012] As used herein with the various illustrated embodiments described below, the following terms include, but are not limited to, the following meanings.
[0013] The term “shaker screen” means the existing equipment on the drilling site that the invention is meant to clean.
[0014] The term “enclosure” means the ¼″ thick aluminum case that holds the various systems necessary for operation of the device.
[0015] The term “sprayer transport” means the apparatus remote from the enclosure that cleans the shaker screens.
[0016] The term “cleaning solution” means any solution used by the device to clean the shaker screen, typically water or diesel solvent.
[0017] The term “pump system” means the components of the device necessary to pump cleaning solution to the sprayer transport.
[0018] The term “hydraulic system” means the components of the device necessary to move the sprayer transport along the length of the shaker screen.
[0019] The term “pressurized air system” means the components of the device necessary to remove the cleaning solution from the hoses.
[0020] The term “electronic controls” means the components of the device necessary to control and monitor all the systems of the invention.
[0021] The term “power connection” means the components of the device necessary to provide the electrical power required to operate the invention.
[0022] In a preferred embodiment of the invention, the entire structure is powered by a single electric motor ( 1 ), with power of 480 volt AC or equivalent to a total of at least 8 horsepower. This motor powers the Pump System, the Hydraulic System ( 3 ), and the Pressurized Air System ( 4 ). One advantage of a single motor is to be assured that if the motor should fail, then all systems will cease to operate. This feature requires maintenance to be performed before operation can resume, thus avoiding a potential hazard that might arise from any of the systems of the device operating independently.
[0023] Preferably, the Pump System consists of a 13 gallon per minute pump, such as ( 5 ), and the hoses needed to connect the pump to the sprayer transport. The pump is preferably capable of producing between 300 and 1500 psi of pressure, at a rate that would feed the required number of spray tips, while pumping the cleaning solution to the sprayer transport ( 6 ). The pump is driven by the electric motor using a twin drive belt system to insure stability during operation.
[0024] The Hydraulic System ( 3 ) consists of a reservoir tank ( 7 ) to hold the hydraulic fluid, a hydraulic pump ( 13 ) to move the fluid through the system, a flow control valve ( 8 ) to control the pressure of the fluid as it moves through the system, a directional valve ( 9 ) to reverse the flow of the fluid, a filter, and a hydraulic motor ( 10 ) mounted to the sprayer transport ( 6 ). The hydraulic system ( 3 ) operates at a pressure (200-400 psi in a preferred embodiment) required to achieve the power necessary to move the sprayer transport ( 6 ), while the flow control valve ( 8 ) will control the speed at which the spray transport moves across the shaker screen. The directional valve ( 9 ) will change the direction of hydraulic fluid flow as necessary to change the direction of movement of the sprayer transport ( 6 ).
[0025] The Pressurized Air System ( 4 ) consists of an air compressor pump ( 14 ), an air compressor tank ( 15 ), an unloader valve ( 16 ), and a one way check valve ( 17 ). The air compressor pump ( 14 ) is driven by the electric motor ( 1 ) using a single belt configuration. The pressurized air system ( 4 ) builds pressure in the tank to approximately 150 psi. When pressure in the system begins to reach 150 psi, the unloader valve ( 16 ) will release pressure in the system into the atmosphere in order to maintain a constant safe pressure in the system. When the pressure in the pump system falls below 150 psi, signifying that cleaning fluid is no longer being pumped, the check valve ( 17 ) will open, allowing the pressurized air to blow out the fluid lines as necessary in order to prevent freezing in the lines during cold weather operation.
[0026] The sprayer transport ( 6 ) consists of an I-beam transport bar ( 18 ), a universal mounting bracket ( 19 ), a transport assembly ( 20 ), a spray bar ( 21 ), and a transport cover ( 22 ). The I-beam transport bar ( 18 ) is installed using the universal mounting bracket across the entire length of the shaker screen. The sprayer transport ( 6 ) is then installed on the transport bar ( 18 ) via a spring loaded tensioner that holds the assembly to the transport bar and provides the necessary tension for the transport assembly ( 20 ) to move across the bar. The spray bar ( 21 ) preferably consists of five or seven 0.2 gallon per minute nozzles as required by each shaker screen model. The sprayer angle may preferably be 15 to 60 degrees as required by each shaker screen model.
[0027] In a preferred embodiment, the sprayer transport mechanism has two possible configurations, one being the standard model that will operate on all shaker screen models without covers and a low profile model that can operate on shaker screen models with covers or on stacked shaker screen models that have limited headroom between the upper and lower shaker screens. This configuration will employ a C-channel transport bar. However, the sprayer transport mechanism has many possible configurations, including that the spray transport could be chain driven, or belt driven, or could work on a slide that moves via pressure created from the spray pump.
[0028] The sprayer transport preferably connects remotely to the enclosure via two hoses, each 100 feet in length, and one 100 foot cleaning fluid hose. Each enclosure can operate up to three sprayer transports, thus allowing a single shaker screen cleaner to clean up to three shaker screens. The hose could alternatively be of other convenient lengths and could power any number of sprayer transports, given an adequate pump and motor combination, up to a pressure that is not so high as to damage the spray screens themselves.
[0029] The preferable cleaning fluid pressure for 1-3 spray bars in the preferred embodiment is between 200-800 psi.
[0030] The electronic controls ( 11 ), in a preferred embodiment, consist of an explosion proof (Class 1 Division 2, Zone 1 ATEX) housing for the electronics, a starter switch for the motor, timer circuitry, and supporting electronics. Starting may be effected by a manual switch or automatically via a programmable logic controller (PLC) controlled starter; both are included in the electrical controls in a preferred embodiment. The timer circuitry controls at what interval the shaker screen is cleaned, the duration of the cleaning cycle during this interval, and also for the sprayer transport as it travels the length of the shaker screen. These parameters can be programmed into the PLC controlled starter mechanism or can be set using discreet components as required per customer request. The supporting electronics consist of a step down transformer, fuses, and associated wiring necessary for operation.
[0031] The power connection ( 12 ) preferably consists of approximately 100 feet of SO 10/4 electrical cable, explosion proof Class 1 Zone 1 plugs attached to each end of the cable, and an explosion proof (Class 1 Zone 1) receptacle mounting on the enclosure. The power connection is suitable for hazardous area duty and can deliver the 480 volts AC @ 30 amps to the enclosure necessary for proper and safe operation of the invention.
[0032] Preferably, the components are corrosion-resistant, and are not intended, separately or as assembled, to be submersed.
[0033] The various components are preferably designed to work in hazardous conditions, including but not limited to oil rig drilling sites, mining operations, extreme cold, and extreme heat. All electrical devices that make or break electrical connections are preferably either housed in the explosion proof control housing or the components themselves are rated as explosion proof from the manufacturer.
[0034] The power cable will preferably be connected to local power at the work site and to the device of the invention. The cable is preferably constructed using 2 types of connecters, one being the standard APC connection common in oil and mining operations, the other being a CPH connection that mates with the receptacle on the invention device. This is to insure the proper cable is used to power the device of this invention. It is possible to have the device enclosure preferably up to 100 feet from the power source as necessary.
[0035] The sprayer transport and the transport bar will be installed on the shaker screen and connected to the enclosure via the proper hoses and power cord (including 2 hydraulic hoses and the cleaning solution hose in a preferred embodiment). It is possible to have the enclosure up to 100 feet or more from the shaker screen as necessary.
[0036] Once the device is powered on and in the auto position, the starter switch will preferably start the electric motor and all systems will be operational as the motor comes up to full speed. The device will then begin the operation of cleaning the shaker screen at the interval programmed on the PLC, or via the discreet timers as the customer requires. A typical cleaning cycle preferably would run the sprayer transport back and forth 1-4 times along the transport bar, taking approximately 11-30 seconds for each length of the transport bar to clean the shaker screens. The device preferably would then shut down for 5-30 minutes, and the process would be repeated during the drilling or mining operation.
[0037] When the device is powered up, in the preferred embodiment, the following will take place simultaneously:
The hydraulic system will begin to pump fluid through the hydraulic hoses at a flow rate necessary to support an interval of approximately 11-30 seconds for the sprayer transport to traverse the transport bar. When the timer controlling the sprayer transport has run for approximately 11-30 seconds per direction, then the sprayer transport will reverse direction. The pump system will begin to pump cleaning solution to the spray bars located on the sprayer transport. Each spray bar will preferably contain 5 or 7 nozzles, and will provide a downward spray of approximately 200-800 psi as the sprayer transport moves across the shaker screen, cleaning debris from the shaker screen.
[0040] The pressurized air system will begin to fill the air tank to an appropriate pressure to purge the lines, approximately 150 psi in a preferred embodiment, and hold that pressure in the system until the cleaning cycle has ended.
[0041] When the cleaning cycle has ended, the device will preferably shut off, and when the pressure in the pump system falls below approximately 150 psi, the check valve will open and the pressurized air system will blow air through the cleaning solution hoses in order to evacuate all the fluid, thereby eliminating the possibility of cleaning fluid freezing in the hoses.
[0042] It will be apparent to those skilled in the art that various modifications and changes to the structures, dimensions, and features described herein may be made without departing from the spirit of the invention and the scope of the appended claims. | The Automatic Shaker Screen Cleaner of this invention enables the efficient cleaning of the large shaker screens that are often used in petroleum extraction and mining operations. This Automatic Shaker Screen Cleaner includes a pump system to deliver water or solvent fluid to clean the shaker screens; a motor system to move the cleaning apparatus back and forth to facilitate the cleaning of the shaker screens; a pressurized air system to clean the hoses when the device is not in use, as well as the electronic controls and power connections required to safely operate the Cleaner. | 1 |
BACKGROUND OF THE INVENTION
1. Technical Field
The present invention relates to methods of manufacturing fluid-dynamic-pressure bearing units employed as bearing devices in applications such as spindle motors for hard-disk drives, and to motors employing such fluid-dynamic-pressure bearing units.
2. Description of the Related Art
As bearings for motors in which high rotational precision is demanded—as is the case with spindle motors employed in disk drives that drive recording disks such as hard disks, and with motors for driving the polygonal mirrors of laser printers—in order to support the shaft and sleeve letting one rotate relative to the other, fluid-dynamic-pressure bearing units that employ the fluid pressure of a lubricant such as oil intervening in between the two have variously been proposed to date.
One example of a motor that employs such fluid-dynamic-pressure bearing units is illustrated in FIG. 1 . This conventional dynamic-pressure-bearing employing motor is configured with a pair of radial bearings 4 , 4 in between the outer circumferential surface of a shaft 2 that forms a single component with a rotor 1 , and the inner circumferential surface of a sleeve 3 through which the shaft 2 is inserted and in which it is free to rotate. In between the upper surface of a discoid thrust plate 5 that projects radially outward from the outer circumferential surface of one of the end portions of the shaft 1 , and the flat surface of a step recessed into the sleeve 3 , as well as in between the undersurface of the thrust plate 5 and a thrust bush 6 that closes off one of the openings in the sleeve 3 , the motor is also configured with a pair of respective thrust bearings 7 , 7 .
Consecutive micro-gaps between the shaft 2 together with the thrust plate 5 and the sleeve 3 together with the thrust bush 6 form bearing clearances, and oil 9 as a lubricating fluid is retained continuously without interruption within these bearing clearances. (This sort of oil-retaining structure will be denoted a “full-fill structure” hereinafter.)
Herringbone grooves 41 , 41 and 71 , 71 composed of linked pairs of spiral striations are formed in the radial bearings 4 , 4 and the thrust bearings 7 , 7 . In response to the rotor 1 rotating, maximum dynamic pressure is generated in the center portion of the bearings, which is where the spiral-striation joints are located. Loads acting on the rotor 1 are borne by this dynamic pressure.
In a motor of this sort, a taper seal section 8 is formed alongside a portion of the sleeve 3 at its upper end, located on the motor end axially opposite the thrust bearings 7 , 7 , wherein the surface tension of the oil and the atmospheric pressure balance to constitute a boundary surface. This means that the oil internal pressure within the taper seal section 8 is maintained at a pressure that is essentially equal to atmospheric pressure.
One method that has been proposed as a way of charging bearings, configured as described above, with the oil 9 as retained in between the shaft 2 with the thrust plate 5 and the sleeve 3 with the thrust bush 6 is as follows. A vacuum chamber stocked with oil is pumped down to a vacuum level, wherein a stirring device is operated to agitate and degas the oil. Then a vacuum chamber in which the bearing unit is retained is pumped down to a vacuum level, following which the oil is supplied to the vacuum chamber that retains the bearing unit, so as to put an appropriate amount of oil under a reduced-pressure environment into the bearing-unit opening, including the taper seal section 8 for the bearings. Subsequently the environment within the vacuum chamber that retains the bearing unit is brought back to atmospheric pressure, thereby exploiting the pressure difference so as to charge the bearing clearances in the fluid-dynamic-pressure bearing unit with the oil.
With oil-charging methods of the sort just described, however, air that has dissolved into the oil in the course of the oil-charging procedure, or at the stage in which after assembly as a fluid-dynamic-pressure bearing is complete the bearing is incorporated into a motor and put to work, sometimes is manifested as air bubbles.
This is thought to originate in air, slight though it may be, remaining dissolved within the oil even after having undergone the degassing process, because even with the vacuum chamber being pumped down to a vacuum level, artificially creating a perfect vacuum state is impossible. Air bubbles becoming manifest during the oil-charging procedure can hinder the smooth supply of oil from the vacuum chamber that stores oil to the vacuum chamber that holds the bearing unit, or, at the stage in which the oil has arrived inside the vacuum chamber that holds the bearing unit, can foam the oil such that the oil spouts out and sticks to the bearing unit and the vacuum-chamber interior, making it necessary to wipe the oil off, and such consequences cause a drop-off in productivity.
Moreover, if the motor is run with air bubbles within the oil mixed in as they are, eventually either of two of the following problems will arise. One affects the endurance and reliability of the motor and is a problem of the air bubbles expanding in volume-due, for example, to a rise in temperature-and causing the oil to leak out to the bearing-unit exterior. The other affects the rotational precision of the motor and is a problem of incidents of vibration or a problem of deterioration from NRRO (non-repeatable runout), due to the air bubbles coming into contact with the dynamic-pressure-generating grooves provided in the bearings.
Additional problems with the bearing oil-charging method discussed above involve a stirring propeller within the oil stored inside the vacuum chamber. Via a drive train including a shaft the propeller is linked to a drive source disposed on the exterior of the vacuum chamber. If the portion of the vacuum chamber through which the shaft passes is not hermetically sealed, then when the propeller is rotated to agitate and degas the oil, leaking of oil and dissolving of air into the oil will occur. The occurrence of such problems creates management difficulties. Furthermore, in that simply stirring the oil by the rotation of the propeller alone entails an extremely lengthy degassing operation in order to purge the oil completely of the air dissolved into it, a further concern is the consequent loss in productivity in the manufacture of fluid-dynamic-pressure bearing units.
One further concern in the manufacture of fluid-dynamic-pressure bearing units is that despite the oil having undergone a degassing process as described above, in rare instances air bubbles will be generated within the oil in installing the bearing unit into a motor and putting it to work. In such instances, given that it is unclear whether the generated air bubbles remain from or were mixed in during the oil-charging procedure, or became freshly mixed-in within the oil from the motor being driven, it is difficult to single out whether the cause is an operational shortcoming in the oil-charging procedure, or is a structural defect in, or a machining-operational shortcoming in the production of, the fluid-dynamic-pressure bearing units themselves. The consequence is that inspecting/testing to determine the cause and then finding the most appropriate way to eliminate the in-mixing of air into the oil requires an inordinate amount of time.
BRIEF SUMMARY OF THE INVENTION
An object of the present invention is to obviate problems originating in air bubbles being generated within oil charged into the bearing clearances in fluid-dynamic-pressure bearing units, before such problems occur. More specifically, an object of the invention is to make available a method of manufacturing fluid-dynamic-pressure bearing units, and a motor utilizing the fluid-dynamic-pressure bearing units, in which preventing the generation of air bubbles in the course of an oil-charging operation equivalent to a step following the degassing operation is made possible, and in which specifying the causative source of air bubbles in instances in which the generation of air bubbles is detected is made possible.
With a method according to the present invention of manufacturing a fluid-dynamic-pressure bearing, in an implementation in which a degassing process done by vacuum-degassing and stirring-degassing is carried out, a drive source for rotating a stirrer is arranged on the exterior of the vacuum chamber and the stirrer is indirectly rotated, whereby a special configuration for maintaining a hermetic seal on the vacuum chamber is rendered unnecessary. This enables the configuration of the apparatus to be simplified and facilitates management of the hermetic sealing quality.
What is more, by having the reduced-pressure level of the interior of the vacuum chamber storing the oil that has undergone a degassing process—of the oil tank and associated components, which are a vacuum chamber located upstream in terms of the oil-charging procedure—be greater (in other words, in a higher vacuum condition) than the reduced-pressure level within the vacuum chamber for oil-charging, which is located downstream, in terms of the procedure, from the oil-storing vacuum chamber, then even should the charging operation be carried out with oil in which a trace amount of air is still dissolved, the air bubbles will not foam during the procedure and become manifest. These aspects of the invention thus enable the oil-charging procedure to be carried out smoothly.
It should be understood that a method for indirectly rotating the stirrer through a drive source is realizable by a drive technique based on so-called magnetic coupling.
In a further aspect of the present invention, by preparatorily heating the oil when vacuum-degassing and stirring-degassing are carried out, the viscosity of the oil is lowered so that the degassing is expedited, which enables the oil-degassing process to be carried out more efficiently and reliably. An additional benefit is that heating the oil enables volatile impurities contained in the oil to be removed.
Should air have gotten mixed into the oil in an oil-charged fluid-dynamic-pressure bearing unit once it has been incorporated into a motor, then if repeated starting and stopping of the motor gives rise to an elevation of the oil boundary surface within the bearing clearances, or if, while the starting/stopping of the motor is repeatedly carried out, the extent to which the oil boundary surface is elevated increases, either way it will be clear that the basis of the in-mixing of air into the oil lies in the rotation of the motor; in other words, it will be evident that the in-mixing of air continues to occur inasmuch as there is a problem with the structure or processing of the fluid-dynamic-pressure bearing unit. In such instances, simultaneously implementing a plurality of degassing techniques so that the oil-degassing process is carried out with maximal reliability, and meanwhile maintaining the reduced-pressure level of the oil-storing vacuum chamber relative to the reduced-pressure level of the oil-charging vacuum chamber at the relationship described above will at least make it clear that air remnant in or mixed into the oil is not due to some deficiency in the oil-charging operation that includes the degassing process step. Thus, inasmuch as the potential factors giving rise to the problem are narrowed down to a defect in either the structure or processing of the fluid-dynamic-pressure bearing unit, singling out the causative source is facilitated, enabling prompt testing to establish appropriate measures to address the problem, and enabling the implementation of those measures.
From the following detailed description in conjunction with the accompanying drawings, the foregoing and other objects, features, aspects and advantages of the present invention will become readily apparent to those skilled in the art.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
FIG. 1 is a configurational diagram of a motor that includes a fluid-dynamic-pressure bearing; and
FIG. 2 is a conceptional diagram of an oil-charging apparatus that corresponds to an embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
The object of obviating problems originating in air bubbles being generated within oil charged into the bearing clearances in fluid-dynamic-pressure bearing units, before such problems occur, was realized without increasing operational man-hours needed or complicating the operational steps. The invention also accomplished the other object, which is to make it possible to single out the causative source of air bubbles in instances in which the generation of air bubbles is detected, without increasing man-hours needed or complicating the steps in the process.
Below, reference is made to the appended drawings to discuss a method of manufacturing fluid-dynamic-pressure bearing units according to the present invention. A fluid-dynamic-pressure bearing unit 10 has the same configuration as the fluid-dynamic-pressure bearing shown in FIG. 1 and therefore, the configuration thereof is not elaborated upon to avoid repetitive description.
In a method according to the present embodiment of manufacturing a fluid-dynamic-pressure bearing unit, first, a heater H is turned on to heat oil L that is stored inside a first vacuum chamber 100 , which is an oil tank; the oil is heated to a temperature within a range of about 80° C. to about 100° C., preferably to be about 90° C., and a valve B 1 is released to operate a vacuum pump P 1 to discharge the air inside the first vacuum chamber 100 and pump the chamber down to a predetermined level of vacuum PL 1 . Upon confirming that the temperature of the oil L has reached about 90° C. and that the reduced-pressure level inside the first vacuum chamber 100 has reached the vacuum level PL 1 , a motor M, which is fitted to the first vacuum chamber 100 with the heater H interposed therebetween, is run at a rotational speed of about 600 rpm. The motor M has a rotor (not shown) on which a magnet is mounted, so that a stirrer S, immersed in the oil and made of a magnetic material, also starts to rotate attendant upon rotation of the motor M to stir the oil L. At that time, the vacuum level PL 1 inside the first vacuum chamber 100 is about 100 Pa or lower, and preferably about 30 Pa; the oil L is maintained in that condition for about 30 minutes, and preferably for about 2 hours, so as to be degassed by vacuum and stirring.
Heating the oil L sufficiently when in this way performing the degassing process on the oil L using both vacuum-degassing and stirring-degassing reduces the viscosity of the oil L, making it possible to eliminate the air that has been dissolved into the oil L more efficiently and reliably than by conventional degassing processes using only vacuum-degassing and conventional degassing processes using both vacuum-degassing and stirring-degassing. Moreover, heating the oil L makes it possible to remove volatile impurities contained in the oil L. Additionally, the fact that the stirrer S for carrying out stirring-degassing is rotated by magnetic induction, or so-called magnet coupling, with the motor M, makes it easier to maintain the airtightness of the first vacuum chamber 100 , in comparison with the conventional case in which oil stirring-degassing is carried out by rotating a propeller, coupled via a drive train including a shaft to a drive source disposed on the exterior of the vacuum chamber, within the oil stored inside the vacuum chamber. The stirrer S may be virgate, spherical, annular, or discoid; the stirrer S is formed of a ferromagnetic material such as martensitic or ferritic stainless steel, the surface of which is coated with a soft material such as rubber, or a synthetic resin in which a magnetic material has been blended.
Upon completing the degassing process on the oil L, a fluid-dynamic-pressure bearing unit 10 that has not yet been charged with oil is brought into a second vacuum chamber 106 , which is an oil-charging vessel, through an opening, which is not shown in the figure, and installed in a predetermined position; after closing the opening, a valve B 2 is released and a vacuum pump P 2 is operated to discharge the air inside the second vacuum chamber 106 and inside the bearing clearances of the fluid-dynamic-pressure bearing unit 10 . Then, when a reduced-pressure level PL 2 that has been set in advance is reached, charging of the oil L is launched. It is also possible to pump down the second vacuum chamber 106 by using the vacuum pump P 1 that is used to pump down the first vacuum chamber 100 .
To charge the oil L, first, an oil fill port 108 and a movable piece 110 are translated and rotated so as to be positioned directly above the taper seal section 8 of the fluid-dynamic-pressure bearing unit 10 . Thereafter, the already-degassed oil L stored inside the first vacuum chamber 100 is supplied through a feed line 112 ; for that purpose, a needle valve 114 (for example, a BP-107D made by Ace Giken Co., Ltd.) is operated in order to feed a predetermined amount V 1 of oil into the oil fill port 108 . Next, the oil L supplied from the first vacuum chamber 100 to the needle valve 114 is dripped from the oil fill port 108 into the taper seal section 8 of the fluid-dynamic-pressure bearing unit 10 ; then, outside air that has been made dust-free by means of a filter or the like is allowed to enter by opening a valve B 3 for a predetermined duration, and the air pressure inside the second vacuum chamber 106 is raised from the reduced-pressure level PL 2 . At this time, the interior of the bearing clearances of the fluid-dynamic-pressure bearing unit 10 is in a hermetically-sealed state because of the oil L dripped onto the taper seal section 8 and remains at the reduced-pressure level PL 2 ; thus, a difference in pressure arises between the interior of the bearing clearances and the raised internal pressure of the second vacuum chamber 106 , causing the dripped oil L to be forced into the bearing clearances.
Next, by translating and rotating the movable part 118 , a camera 116 is shifted to a position that permits the interior of the taper seal section 8 to be observed, so that the amount of oil L charged into the bearing clearances through the above-described process can be monitored. Based on the result of the observation, a determination may be made as to whether the amount of oil L charged into the fluid-dynamic-pressure bearing unit 10 is in excess or is insufficient; if the amount of the oil L charged into the bearing unit is insufficient, the requisite amount of oil to be added is determined. Then, again releasing the valve B 2 as needed, the vacuum pump P 2 is operated to discharge the air inside the second vacuum chamber 106 to pump it down to the reduced-pressure level PL 2 . Upon completing the re-pumping down, the necessary oil L is charged into the bearing clearances again in the same manner as the above-described charging process for the amount of oil V 1 . It should be noted that if the oil that has been charged into the bearing clearances is more than the predetermined oil charge amount, the excess portion of the oil is collected by aspirating the excess portion while using the camera 116 to confirm the boundary surface position of the oil L within the taper seal section 8 .
The fluid-dynamic-pressure bearing unit 10 , for which charging with the predetermined amount of oil L has thus been completed, is transferred out of the second vacuum chamber 106 .
In the above-described operation of charging the oil L into the bearing clearances, it is crucial that, at the point when the pump-down is completed, the internal pressure of the first vacuum chamber 100 be lower than the internal pressure of the second vacuum chamber 106 , that is, that the situation be such that reduced-pressure level PL 1 >reduced-pressure level PL 2 .
In supplying the oil L from the first vacuum chamber 100 to the second vacuum chamber 106 , if the relationship between the reduced-pressure levels PL 1 and PL 2 of the respective vacuum chambers 100 and 106 is “reduced-pressure level PL 1 <reduced-pressure level PL 2 ,” that is, if the internal pressure of the first vacuum chamber 100 is higher than the internal pressure of the second vacuum chamber 106 , the pressure difference will cause air remaining to some extent within the oil L to foam due to cavitation and eventually, to spout out from the oil fill port 108 into the second vacuum chamber 106 . Consequently, in an implementation in which the fluid-dynamic-pressure bearing unit 10 is applied as a bearing device to a motor employed under the clean environment of a disk drive or similar device, with the oil L stuck to the surfaces after having spouted out, the oil will contaminate that type of clean environment. Such contamination makes it necessary to wipe off the interior of the second vacuum chamber 106 and the surfaces of the fluid-dynamic-pressure bearing unit 10 . Moreover, if this sort of foaming phenomenon has occurred in the interior of the feed line 112 , the oil L in the interior of the feed line 112 will become partitioned by the foam; if the oil L is thus partitioned, it cannot be supplied smoothly to the oil fill port 108 end of the feed line 112 . Any of these problems will be a factor that will greatly degrade the productivity of the fluid-dynamic-pressure bearing unit 10 .
In contrast, by arranging for the relationship between the reduced-pressure levels PL 1 and PL 2 of the first vacuum chamber 100 and the second vacuum chamber 106 to be, as noted above, “reduced-pressure level PL 1 >reduced-pressure level PL 2 ,” the oil L, while undergoing the oil-charging operation, will be sent to the vacuum chamber in which the pressure, in turn, is higher (and in which the vacuum level is lower), which fully prevents the occurrence of the foaming phenomenon. In order to establish the foregoing pressure relationship, it is desirable that the internal pressure of the second vacuum chamber 106 , in which charging of the oil into the bearing clearances in the fluid-dynamic-pressure bearing unit 10 is carried out, be pumped down to 1000 Pa or less, and preferably to the approximately 100 Pa level.
Next, the fluid-dynamic-pressure bearing unit 10 , for which the operation for charging the bearing with the oil L has been completed as illustrated in FIG. 1 , is put into a motor, and with the fluid-dynamic-pressure bearing unit 10 being incorporated into the motor, by repeatedly starting and stopping the motor and then observing the presence/absence of movement of the boundary surface on the oil within the bearing clearances, and observing the frequency with which such movement occurs, the presence/absence of occurrences of foaming within the oil and the cause of any such occurrences are thereby checked.
Thus, in the fluid-dynamic-pressure bearing unit 10 that has been charged with the oil L, with the bearing unit 10 incorporated into the motor, should air have gotten mixed into the oil L, then if repeated starting and stopping of the motor gives rise to an elevation of the oil L boundary surface within the taper seal section 8 , or if, while the starting/stopping of the motor is repeatedly carried out, the extent to which the oil boundary surface is elevated increases, either way it will be clear that the basis of the in-mixing of air into the oil lies in the rotation of the motor; in other words, it will be evident that the in-mixing of air continues to occur inasmuch as there is a problem with the structure or processing of the fluid-dynamic-pressure bearing unit. In such instances, simultaneously implementing a plurality of degassing techniques so that the process of degassing the oil L is carried out with maximal reliability, and at the same time maintaining the relationship between the reduced-pressure levels PL 1 and PL 2 of the first and second vacuum chambers 100 and 106 at the relationship stated above, will at least make clear that air mixed into the oil L is not due to some deficiency in the oil-charging operation that includes the degassing process step. Thus, inasmuch as the potential factors giving rise to the problem are narrowed down to a defect in either the structure of, or the machining or assembling of, the fluid-dynamic-pressure bearing unit 10 , singling out the causative source is facilitated, enabling prompt testing to establish appropriate measures to address the problem, and enabling the implementation of those measures.
Although in the foregoing discussion, embodiments of a method of manufacturing a fluid-dynamic-pressure bearing in accordance with the present invention have been described, the present invention is not limited to these embodiments, and without deviating from the scope of the invention, various changes or modifications are possible; the invention is applicable to a variety of fluid-dynamic-pressure bearing configurations.
For example, a configuration was described in which the first vacuum chamber 100 , where the process of degassing the oil L is carried out, and the second vacuum chamber 106 , which is for oil injection, are directly linked by means of the feed line 112 , but another option is to interpose a special reservoir for storing oil between the first vacuum chamber 100 and the second vacuum chamber 106 . With that option, when actually charging the oil L into the bearing clearances within the fluid-dynamic-pressure bearing unit 10 , by having the relationship between the reduced-pressure level in the oil reservoir and the reduced-pressure level PL 2 in the second vacuum chamber 106 be “reduced-pressure level in oil reservoir>reduced-pressure level PL 2 in the second vacuum chamber 106 ,” the foaming phenomenon will not occur. | Fluid-dynamic-pressure bearing manufacturing method for more efficient and fail-safe degassing of bearing oil. Method makes it possible to prevent the generation of air bubbles in the course of an oil-charging operation that amounts to a step following degassing, and to single out the causative source of air bubbles when their generation has been detected. At the same time oil that is under a reduced-pressure environment within an oil-storing vacuum chamber is vacuum-degassed, immersed within the oil a stirrer for agitating and degassing the oil is rotated by indirect drive means, and the oil after having been degassed is supplied to a vacuum chamber where a fluid-dynamic-pressure bearing unit is retained—which has been pumped down to a pressure below the pressure within the oil-storing vacuum chamber—and is charged into the bearing clearances by raising the internal pressure of the bearing-retaining vacuum chamber. | 5 |
FIELD OF THE INVENTION
[0001] The present invention relates to inhibitors of cysteine proteases, especially to inhibitors of the cysteine protease legumain. This invention relates further to pharmaceutical compositions containing one or more inhibitors of the legumain activity. The pharmaceutical compositions, comprising one or more legumain inhibitors according to the present invention are useful for the treatment of legumain mediated diseases in a patient or subject, such as immune or autoimmune diseases.
BACKGROUND OF INVENTION
[0002] Legumain was discovered in 1993 in plants, where the enzyme is present in legumes and in seeds of other plants. Then legumain was cloned, isolated and characterized from different species, e.g. from mouse, and from pig kidney. Human legumain was characterized after over-expression in a murine cell line.
[0003] The catalytic dyad is found in the motif His-Gly-spacer-Ala-Cys, and was confirmed by si-directed mutagenesis. Due to the presence of the same motif in caspases, clostripain, gingipain and separase these proteases where classified as Clan CD. Legumain is inhibited by iodoacetamid, maleimides, and ovocystatin, but is unaffected by E64.
[0004] Mammalian legumain is a lysosomal enzyme being highly specific for post-asparagine cleavage. It has been shown that the cleavage is inhibited by the glycosylation of the P1-asparagine residue. Furthermore, it is involved in the processing of antigens for the class II MHC presentation.
[0005] Different isoforms of legumain were purified from a plant source (seeds of kidney bean, Phaseolus vulgaris ) and a mammal (kidney of pig, Sus scropha ).
[0000] Autoimmune Reactions
[0006] Sometimes the immune system malfunctions, misinterprets the body's tissues as foreign, and attacks them, resulting in an autoimmune reaction. Autoimmune reactions can be triggered in several ways:
[0007] A substance in the body that is normally strictly contained in a specific area (and thus is hidden from the immune system) is released into the general circulation. For example, the fluid in the eyeball is normally contained within the eyeball's chambers. If a blow to the eye releases this fluid into the bloodstream, the immune system may react against it. A normal body substance is altered. For example, viruses, drugs, sunlight, or radiation may change a protein's structure in a way that makes it seem foreign. The immune system responds to a foreign substance that is similar in appearance to a natural body substance and inadvertently targets the body substance as well as the foreign substance. Something malfunctions in the cells that control antibody production. For example, cancerous B lymphocytes may produce abnormal antibodies that attack red blood cells. The results of an autoimmune reaction vary. Fever is common. Various tissues may be destroyed, such as blood vessels, cartilage, and skin. Virtually any organ can be attacked by the immune system, including the kidneys, lungs, heart, and brain. The resulting inflammation and tissue damage can cause kidney failure, breathing problems, abnormal heart function, pain, deformity, delirium, and death.
[0008] A large number of disorders almost certainly have an autoimmune cause, including lupus (systemic lupus erythematosus), myasthenia gravis, Graves' disease, Hashimoto's thyroiditis, pemphigus, rheumatoid arthritis, scleroderma, Sjögren's syndrome, pernicious anemia, multiple sclerosis and type I diabetes.
[0009] Immune diseases include but are not limited to conditions involving T-cells and/or macrophages such as acute and delayed hypersensitivity, graft rejection and graft-versus-host disease.
REFERENCE LIST
[0000]
Carpino, L. A.; Giza, C. A.; Carpino, B. A. O-Acylhydroxylamines. I. Synthesis of O-Benzoylhydroxylamine. J. Am. Chem. Soc. 1959, 81, 955-957.
Fehrentz, J. A.; Castro, A. An Efficient Synthesis of Optically Active—(t-Butoxycarbonylamino)-aldehydes from—Amino Acids. Synthesis 2000, 8, 676-678.
Niedrich, H. Chem. Ber. 1969, 102, 1557-1569.
Shahak, I.; Almog, J. Synthesis 1969, 170-172.
Yasuma, T.; Oi, S.; Choh, N.; Nomura, T.; Furuyama, N.; Nishimura, A.; Fujisawa, Y.; Sohda, T. J. Med. Chem. 1998, 41, 4301-4308.
SUMMARY OF THE INVENTION
[0015] The invention relates to inhibitors of cysteine proteases having the general formulas I or II below:
wherein:
[0016] As stands for any amino acid, or mimetics thereof and where Y stands for any acyl-residue including urethanes and peptides, preferably peptides having 2 to 10 amino acids, or any alkyl residue. Examples of amino acids which can be used in the present invention are L and D-amino acids, N-methyl-amino-acids; allo- and threo-forms of Ile and Thr, which can, e.g. be α-, β- or ω-amino acids, whereof α-amino acids are preferred.
[0017] Examples of amino acids are:
[0018] aspartic acid (Asp), glutamic acid (Glu), arginine (Arg), lysine (Lys), histidine (His), glycine (Gly), serine (Ser) and cysteine (Cys), threonine (Thr), asparagine (Asn), glutamine (Gln), tyrosine (Tyr), alanine (Ala), proline (Pro), valine (Val), isoleucine (Ile), leucine (Leu), methionine (Met), phenylalanine (Phe), tryptophan (Trp), hydroxyproline (Hyp), beta-alanine (beta-Ala), 2-amino octanoic acid (Aoa), azetidine-(2)-carboxylic acid (Ace), pipecolic acid (Pip), 3-amino propionic, 4-amino butyric and so forth, alpha-aminoisobutyric acid (Aib), sarcosine (Sar), ornithine (Orn), citrulline (Cit), homoarginine (Har), t-butylalanine (t-butyl-Ala), t-butylglycine (t-butyl-Gly), N-methylisoleucine (N-Melle), phenylglycine (Phg), cyclohexylalanine (Cha), norleucine (Nle), cysteic acid (Cya) and methionine sulfoxide (MSO), Acetyl-Lys, modified amino acids such as phosphoryl-serine (Ser(P)), benzyl-serine (Ser(Bzl)) and phosphoryl-tyrosine (Tyr(P)), 2-aminobutyric acid (Abu), aminoethyicysteine (AECys), carboxymethylcysteine (Cmc), dehydroalanine (Dha), dehydroamino-2-butyric acid (Dhb), carbbxyglutaminic acid (Gla), homoserine (Hse), hydroxylysine (Hyl), cis-hydroxyproline (cisHyp), trans-hydroxyproline (transHyp), isovaline (Iva), pyroglutamic acid (Pyr), norvaline (Nva), 2-aminobenzoic acid (2-Abz), 3-aminobenzoic acid (3-Abz), 4-aminobenzoic acid (4-Abz), 4-(aminomethyl)benzoic acid (Amb), 4-(aminomethyl)cyclohexanecarboxylic acid (4-Amc), Penicillamine (Pen), 2-Amino-4-cyanobutyric acid (Cba), cycloalkane-carboxylic aicds.
[0019] Examples of ω-amino acids are e.g.: 5-Ara (aminoraleric acid), 6-Ahx (aminohexanoic acid), 8-Aoc (aminooctanoic aicd), 9-Anc (aminovanoic aicd), 10-Adc (aminodecanoic acid), 11-Aun (aminoundecanoic acid), 12-Ado (aminododecanoic acid).
[0020] Further amino acids are: indanylglycine (Igl), indoline-2-carboxylic acid (Idc), octahydroindole-2-carboxylic acid (Oic), diaminopropionic acid (Dpr), diaminobutyric acid (Dbu), naphtylalanine (1-Nal), (2-Nal), 4-aminophenylalanin (Phe(4-NH 2 )), 4-benzoylphenylalanine (Bpa), diphenylalanine (Dip), 4-bromophenylalanine (Phe(4-Br)), 2-chlorophenylalanine (Phe(2-Cl)), 3-chlorophenylalanine (Phe(3-Cl)), 4-chlorophenylalanine (Phe(4-Cl)), 3,4-chlorophenylalanine (Phe (3,4-Cl 2 )), 3-fluorophenylalanine (Phe(3-F)), 4-fluorophenylalanine (Phe(4-F)), 3,4-fluorophenylalanine (Phe(3,4-F 2 )), pentafluorophenylalanine (Phe(F 5 )), 4-guanidinophenylalanine (Phe(4-guanidino)), homophenylalanine (hPhe), 3-jodophenylalanine (Phe(3-J)), 4 jodophenylalanine (Phe(4-J)), 4-methylphenylalanine (Phe(4-Me)), 4-nitrophenylalanine (Phe-4-NO 2 )), biphenylalanine (Bip), 4-phosphonomehtylphenylalanine (Pmp), cyclohexyglycine (Ghg), 3-pyridinylalanine (3-Pal), 4-pyridinylalanine (4-Pal), 3,4-dehydroproline (A-Pro), 4-ketoproline (Pro(4-keto)), thioproline (Thz), isonipecotic acid (Inp), 1,2,3,4,-tetrahydroisoquinolin-3-carboxylic acid (Tic), propargylglycine (Pra), 6-hydroxynorleucine (NU(6-OH)), homotyrosine (hTyr), 3-jodotyrosine (Tyr(3-J)), 3,5-dijodotyrosine (Tyr(3,5-J 2 )), d-methyl-tyrosine (Tyr(Me)), 3-NO 2 -tyrosine (Tyr(3-NO 2 )), phosphotyrosine (Tyr(PO 3 H 2 )), alkylglycine, 1-aminoindane-1-carboxy acid, 2-aminoindane-2-carboxy acid (Aic), 4-amino-methylpyrrol-2-carboxylic acid (Py), 4-amino-pyrrolidine-2-carboxylic acid (Abpc), 2-aminotetraline-2-carboxylic acid (Atc), diaminoacetic acid (Gly(NH 2 )), diaminobutyric acid (Dab), 1,3-dihydro-2H-isoinole-carboxylic acid (Disc), homocylcohexylalanin (hCha), homophenylalanin (hPHe oder Hof), trans-3-phenyl-azetidine-2-carboxylic acid, 4-phenyl-pyrrolidine-2-carboxylic acid, 5-phenyl-pyrrolidine-2-carboxylic acid, 3-pyridylalanine (3-Pya), 4-pyridylalanine (4-Pya), styrylalanine, tetrahydroisoquinoline-1-carboxylic acid (Tiq), 1,2,3,4-tetrahydronorharmane-3-carboxylic acid (Tpi), β-(2-thienyl)-alanine (Tha).
[0021] As can also stand for other amino acids than those encoded in the genetic code.
[0022] Proteinogenic amino acids are defined as natural protein-derived α-amino acids. Non-proteinogenic amino acids are defined as all other amino acids, which are not building blocks of common natural proteins.
Z stands for:
—CO—CH 2 —W where W can be H, an optionally substituted alkyl, alkenyl, alkynyl, carbocyclic, aryl, heteroaryl, heterocyclic, N 2 , halogen, O-alkyl, O-alkenyl, O-alkynyl, O-carbocyclic, O-aryl, O-heteroaryl, O-heterocyclic, O-acyl, S-alkyl, S-alkenyl, S-alkynyl, S-carbocyclic, S-aryl, S-heteroaryl, S-heterocyclic, S-acyl, C(O)-alkyl, C(O)-alkenyl, C(O)-alkynyl, C(O)-carbocyclic, C(O)-aryl, C(O)-heteroaryl, or C(O)-heterocyclic residue, or N + (RR′R″), where R, R′ and R″ are independently from each other an optionally substituted acyl, alkyl, alkenyl, alkynyl, carbocyclic, aryl, heteroaryl, or heterocyclic residue, or —CO—NHO-Q where Q can be an optionally substituted acyl, alkenyl, alkynyl, aroyl, carbocyclic, heteroaryl, heterocyclic, aryl, or alkyl residue, or —CR 1 ═CR 2 -EWG where R 1 and R 2 are independently from each other H, an optionally substituted alkyl, alkenyl, alkynyl, carbocyclic, heteroaryl, heterocyclic, or aryl residue, and are in cis or trans position to each other; and where EWG represents any electron-withdrawing group including
OR 4 , where R 4 can be H, an optionally substituted alkyl, alkenyl, alkynyl, carbocyclic, heteroaryl, heterocyclic or aryl residue, or C(O)O—R 5 where R 5 can be H, an optionally substituted alkyl, alkenyl, alkynyl, carbocyclic, heteroaryl, heterocyclic, acyl, aryl, or a substituted residue thereof, or CH 2 O—R 6 where R 6 can be H, an optionally substituted alkyl, alkenyl, alkynyl, carbocyclic, heteroaryl, heterocyclic, acyl or aryl residue, or CN, or SO 2 R 7 where R 7 can be H, an optionally substituted alkyl, alkenyl, alkynyl, carbocyclic, heteroaryl, heterocyclic, acyl or aryl residue, or PO 2 OR 8 where R 8 can be H, an optionally substituted alkyl, alkenyl, alkynyl, carbocyclic, heteroaryl, heterocyclic, acyl or aryl residue.
[0034] Throughout the description and the claims the expression “acyl” can denote a C 1-20 acyl residue, preferably a C 1-8 acyl residue and especially preferred a C 1-4 acyl residue, “carbocyclic” or cycloalkyl can denote a C 3-12 carbocyclic residue, preferably a C 4 , C 5 or C 6 carbocyclic residue. “Heteroaryl” is defined as an aryl residue, wherein 1 to 4, preferably 1, 2 or 3 ring atoms are replaced by heteroatoms like N, S or O. “Heterocyclic” is defined as a cycloalkyl residue, wherein 1, 2 or 3 ring atoms are replaced by heteroatoms like N, S or O. The expression “alkyl” can denote a C 1-50 alkyl group, preferably a C 6-30 alkyl group, especially a C 8-12 alkyl group; an alkyl group may also be a methyl, ethyl, propyl, isopropyl or butyl group. The expression “aryl” is defined as an aromatic residue, preferably substituted or optionally unsubstituted phenyl, benzyl, naphthyl, biphenyl or anthracene groups, which preferably have at least 8 C ring atoms; the expression “alkenyl” can denote a C 2-10 alkenyl group, preferably a C 2-6 alkenyl group, which has the double bond or the double bonds at any desired location and may be substituted or unsubstituted; the expression “alkynyl” can denote a C 2-10 alkynyl group, preferably a C 2-6 alkynyl group, which has the triple bond or the triple bonds at any desired location and may be substituted or unsubstituted; the expression “alkoxy” can denote a C 1-50 alkyl-oxygen group; the expression “alkenyloxy” can denote a C 2-10 alkenyl-oxygen group; the expression “alkynyloxy” can denote a C 2-10 alkynyl-oxygen group; the expression “carbocyclicoxy” can denote a C 3-12 carbocyclic-oxygen group; the expression “heteroaryloxy” can denote an aryl-oxygen group, wherein 1 to 4, preferably 1, 2 or 3 ring atoms are replaced by heteroatoms like N, S or O; the expression “heterocyclicoxy” can denote cycloalkyl-oxygen group, wherein 1, 2 or 3 ring atoms are replaced by heteroatoms like N, S or O; the expression “substituted” can denote any desired substitution by one or more, preferably one or two, alkyl, alkenyl, alkynyl, mono- or multi-valent acyl, alkoxy, alkoxyacyl, alkenyloxy, alkynyloxy, carbocyclicoxy, heteroaryloxy, heterocyclicoxy, alkoxyalkyl groups, any monoether or polyether containing identical or different alkyl, aryl, alkenyl, alkynyl, carbocyclic, heteroaryl, heterocyclic residues, or any monothioether or polythioether containing identical or different alkyl, aryl, alkenyl, alkynyl, carbocyclic, heteroaryl, heterocyclic residues; the afore-mentioned substituents may in turn have one or more (but preferably zero) alkyl, alkenyl, alkynyl, mono- or multi-valent acyl, alkoxyacyl or alkoxyalkyl groups as side groups which are preferably not substituted themselves. Organic amines, amides, alcohols or acids, each having from 8 to 50 C atoms, preferably from 10 to 20 C atoms, can have the formulae (alkyl) 2 N— or alkyl-NH—, —CO—N(alkyl) 2 or —CO—NH(alkyl), -alkyl-OH or -alkyl-COOH.
[0035] The expression urethanes can denote a compound of the formula R″′NH—CO—OR″″, wherein R″′ and R″″ are independently from each other optionally substituted alkyl, alkenyl, alkynyl, carbocyclic, heteroaryl, heterocyclic or aryl residues.
[0036] Peptide mimetics per se are known to a person skilled in the art. They are preferably defined as compounds which have a secondary structure like a peptide and optionally further structural characteristics; their mode of action is largely similar or identical to the mode of action of the native peptide; however, their activity (e.g. as an antagonist or inhibitor) can be modified as compared with the native peptide, especially vis à vis receptors or enzymes. Moreover, they can imitate the effect of the native peptide (agonist). Examples of peptide mimetics are scaffold mimetics, non-peptidic mimetics, peptoides, peptide nucleic acids, oligopyrrolinones, vinylogpeptides and oligocarbamates. For the definitions of these peptide mimetics see Lexikon der Chemie, Spektrum Akademischer Verlag Heidelberg, Berlin, 1999.
[0037] The aim for using these mimetic structurs is increasing the activity, increasing the selectivity to decrease side effects, protect the compound (drug) against enzymatical degradation for prolongation of the effect.
[0038] Further peptide mimetics are defined in J. Gante, Angew. Chemie, 1994, 106, 1780-1802; V. J. Hruby et al., Biopolymers, 1997, 219-266; D. Nöteberg et al., 2000, 43, 1705-1713.
[0039] The present invention further includes within its scope prodrugs of the compounds of this invention. In general, such prodrugs will be functional derivatives of the compounds which are readily convertible in vivo into the desired therapeutically active compound. Thus, in these cases, the use of the present invention shall encompass the treatment of the various disorders described with prodrug versions of one or more of the claimed compounds, but which converts to the above specified compound in vivo after administration to the subject. Conventional procedures for the selection and preparation of suitable prodrug derivatives are described, for example, in “Design of Prodrugs”, ed. H. Bundgaard, Elsevier, 1985.
[0040] Where the compounds according to this invention have at least one chiral center, they may accordingly exist as enantiomers. Where the compounds possess two or more chiral centers, they may additionally exist as diastereomers. It is to be understood that all such isomers and mixtures thereof are encompassed within the scope of the present invention. Furthermore, some of the crystalline forms of the compounds may exist as polymorphs and as such are intended to be included in the present invention. In addition, some of the compounds may form solvates with water (i.e. hydrates) or common organic solvents, and such solvates are also intended to be encompassed within the scope of this invention.
[0041] These compounds are inhibitors of the cysteine protease legumain. These inhibitors may be used in pharmaceutical compositions. The pharmaceutical compositions, comprising one or more legumain inhibitors according to the present invention are useful for the treatment of legumain mediated diseases in a patient or subject.
DETAILED DESCRIPTION OF THE INVENTION
[0000] Biological Evaluation
[0042] The compounds were tested as inhibitors of legumain and checked for their cross-reactivity against two more cysteine proteases namely papain and cathepsin B. The activities are given in tables 1-3 for selected compounds of formulas 1-3.
[0043] No inhibition of papain and cathepsin B was observed at concentrations below 0.1 mM. The α,β-unsaturated compounds of the sulfone and phosphonates showed poor inhibition.
TABLE 1 Activities of the prepared compounds 5-13 Formula 1 Compd no. R 9 EWG k obs /[l] (M −1 s −1 ) 5 H CO 2 CH 3 543 6 H CO 2 CH 2 CH 3 456 7 H CO 2 CH 2 CH═CH 2 776 8 H CO 2 H 4 9 CH 3 CO 2 CH 3 2 10 CH 3 CO 2 CH 2 CH 3 2 11 CH 3 CO 2 H <1 12 H SO 2 CH 3 30 13 H P(O)(OC 2 H 5 ) 2 <1
[0044]
TABLE 2
Activity of the prepared compound 20
Formula 2
Compd no.
K i
20
3.1 ± 0.2 × 10 −6 M
[0045] TABLE 3 Activities of the prepared compounds 18, 22 and 24 Formula 3 Compd no. Z k obs /[l] (M −1 s −1 ) 18 COCH 2 Cl 139088 22 COCH 2 Br 84000 24 COCH 2 OC(O)C 6 H 5 13
Synthesis
[0046] The inhibitors 5-13 were prepared as described in Scheme 1. The tripeptide was prepared starting from Z-Ala-Ala-OH (obtained from Bachem) via Z-Ala-Ala-OSu 1, followed by the coupling reaction with H-Asn(Trt)-OH (obtained from Bachem). The tripeptide-derivated Michael acceptors of the present invention were prepared generally as described in the following procedures. The tripeptide was converted into the aldehyde by reduction of the corresponding Weinreb amide with lithium aluminium hydride. The crude compound was transformed to the desired Michael acceptor compounds by the Wittig reaction with the corresponding phosphorane (Method A) or the Horner-Emmons reaction of the corresponding phophate ester with sodium bis(trimethylsilyl)amide or sodium hydride (Methods B, C). The trityl protecting group was removed by TFA in the presence of triisopropylsilane to give the inhibitors in good yields (Method D). The crude compounds were purified by preparative HPLC to give the desired inhibitors (Examples 1-9, compound 5-13).
[0047] The inhibitors 18, 22 and 24 were prepared as described in Scheme 2. The compound tert.-Butyl 2-(hydrazino)acetic acid was prepared from 80% hydrazine hydrate and t-butylbromoacetate according to the procedure of Niedrich, 1969. The hydrazine was coupled with Z-Ala-Ala-OSu 1 (prepared as described in Experimentals, Starting Material) to obtain the compound 14. Treatment of the t-butyl ester with TFA in dichloromethane provided the compound 15, which was converted into the compound 16 via coupling reaction with HATU, HOAt and triphenylmethylamine. Acylation with chloroacetyl chloride or bromoacetyl bromide gave the corresponding chloroacetyl and bromoacetyl derivative 17 and 21. The trityl protecting group was removed by TFA in the presence of triisopropylsilane to give the inhibitor 2-[2-(Cbz-L-Ala-L-Ala)-1-chloroacetyl)hydrazino]acetamide 18 and 22 (Method D). Treatment of 21 with benzoic acid in the presence of potassium fluoride was followed by treatment with trifluoroacetic acid (Method D) generated the benzoyloxymethylketone 24. The asparagine analogues were recognised by the protease resulting in potent inhibition. The second-order rate constant for the inactivation of legumain by the chloromethylketone (18), 139088 M −1 s −1 is approximately 200 fold higher than that of the Michael acceptor inhibitors (Table 3). Whereas the bromomethylketone (22) is another potent inhibitor, the benzoyloxymethylketone (24) displays only moderate inhibition. Neither papain nor cathepsin B is inhibited by these inhibitors.
[0048] Furthermore we describe the preparation of another inhibitor 20 (Scheme 3) based on the N-peptidyl-O-acyl hydroxylamines Xaa-CO—NHO—CO—.
Experimental
[0049] NMR spectra were performed on Varian Unity 500, Varain Gemini 200 and Bruker AM 400 spectrometers. The following abbreviations are used: s, singlet; d, doublet; t, triplet; q, quartet; br., broad. Melting points were measured on a Leica Galen III melting point apparatus. ESI-MS: Mass spectra were taken with an MDS Sciex API 365 mass spectrometer equipped with an Ionspray™ interface (MDS Sciex; Thorn Hill, ON, Canada). The instrument settings, data acquisition and processing were controlled by the Applied Biosystems (Foster City, Calif., USA) Analyst™ software for Windows NT™. 50-100 scans were performed by the positive ionization Q1 scan mode to accumulate the peaks. Sample solutions were diluted with 50% methanol in 0.5% formic acid to reach concentrations about 10 μg/ml. Each sample solution was introduced directly by a microsyringe (1 ml) through an infusion pump (Havard Apperatus 22; Havard Instruments; Holliston, Mass., USA) and fused silica capillary tubing at a rate of 20 μl/min. Thin layer chromatography (TLC) was done with Macherey Nagel Polygram® SIL G/UV 245 . Visualisation was accomplished by means of UV ligth at 254 nm, followed by dyeing with potassium permanganate or ninhydrin. Solvents were distilled prior to use. Petroleum ether with a boiling range of 35-65° C. was used. THF was distilled from sodium diphenyl ketyl immediately before use. All commercially available reagents were used without further purification. Reactions sensitive to air were carried out under an atmosphere of argon. The pH-7 buffer solution used in the workup procedures was prepared by dissolving potassium dihydrogen phosphate (85.0 g) and sodium hydroxide (14.5 g) in water (1 l). The compound dimethyl methylsulfonomethanephosphonate used for the preparation of inhibitor 8 was prepared according to the procedure of Shahak & Almog, 1969. For the purification a preparative HPLC [acetonitrile-water, gradient: 5-95%, flow rate: 6 ml min −1 , column: Nucleosil 7μ C18 100A, 250×21.2 mm (phenomenex), pump: L-6250 Merck-Hitachi] was used.
[0000] General Methods
[0050] Method A (Wittig Reaction):
[0051] To a stirred solution of Z-Ala-Ala-Asn(Trt)-H (0.4 g, 0.63 mmol) in dry THF (10 ml) was added 1.1 equiv. of the corresponding phosphorane, obtained from Aldrich, Inc. The solution was stirred for four days. The solvent was removed under reduced pressure and the obtained residue was purified by flash chromatography to give the desired compounds.
[0052] Method B (Horner-Emmons Reaction, Base: Sodium bis(trimethylsilyl)amide):
[0053] Sodium bis(trimethylsilyl)amide (1.84 ml, 0.756 mmol, prepared from hexamethyidisilazane (427 μl, 2.05 mmol) and sodium amide (80 mg, 2.05 mmol)) in absolute toluol (5 ml) was added to a solution of the corresponding phophate ester (1.2 equiv., 0.756 mmol, obtained from Aldrich, Inc.) in dry THF (4 ml) at 0° C. and stirred for 30 minutes at that temperature. A solution of Z-Ala-Ala-Asn(Trt)-H (0.4 g, 0.63 mmol) in dry THF (1 ml) was added. The mixture was stirred for 1.5 h, during which time it was allowed to warm to room temperature. After cooling with an ice-bath 0.5 N HCl (5 ml) was added and the organic material was extracted five times with ethyl acetate. The combined organic layers were dried over Na 2 SO 4 and concentrated under reduced pressure. The compound was purified by flash chromatography.
[0054] Method C (Horner-Emmons Reaction, Base: Sodium Hydride):
[0055] To a stirred suspension of sodium hydride (18.0 mg, 0.756 mmol, 95%, obtained from Aldrich, Inc.) in THF (4 ml) was added of the corresponding phophate ester (1.2 equiv., 0.756 mmol, obtained from Aldrich, Inc.) at 0° C. The mixture was stirred for 30 minutes at this temperature and a solution of Z-Ala-Ala-Asn(Trt)-H (0.40 g, 0.63 mmol) in dry THF (1 ml) was added. After stirring for 2.5 h at room temperature the mixture was cooled to 0° C. with an ice-bath and quenched with 0.5 N HCl (5 ml). The organic material was extracted five times with ethyl acetate. The combined organic layers were dried over Na 2 SO 4 and concentrated under reduced pressure. The compound was purified by flash chromatography.
[0056] Method D (Deprotecting the Trityl Protecting):
[0057] The trityl protecting group was removed as follows. Triisopropylsilane (277 μl, 1.35 mmol) and trifluoroacetic acid (7.5 ml) were added to a stirred solution of the protected compound (0.27 mmol) in CH 2 Cl 2 (10 ml). This solution was stirred for 30 minutes at room temperature before it was diluted with toluol. The solvents were removed under reduced pressure and the obtained residue was triturated with Et 2 O, and the resulted white solid was purified by preparative HPLC.
[0058] Method E (Saponification):
[0059] The isolated crude product (0.41 mmol) was dissolved in EtOH (3 ml) and 1 M NaOH was added (2.3 equiv. 0.943 mmol). After stirring for 3 h at room temperature the pH of the mixture was adjusted to 2-3 with 1N HCl. The organic material was extracted five times with ethyl acetate. The combined organic layers were dried over Na 2 SO 4 and concentrated under reduced pressure.
[0060] Method F (Esterification):
[0061] The isolated crude compound (0.36 mmol) was dissolved in THF (5 ml) and a immediately before use prepared solution of diazomethane in ether was added until formation of gas ended. After 10 minutes 0.1 N HCl was added (5 ml) and the solvent was removed under reduced pressure. The organic material was extracted five times with ethyl acetate. The combined organic layers were dried over Na 2 SO 4 and concentrated under reduced pressure.
[0000] Starting Material
Synthesis of Z-Ala-Ala-OSu (1)
[0062] The active ester Z-Ala-Ala-OSu (1) was prepared according to a procedure described in Bodansky, M., Bodansky, A., The Practice of Peptide Synthesis 2 nd Edition, Springer-Verlag. To a stirred solution of Z-Ala-Ala-OH (4.0 g, 13.6 mmol, obtained from Bachem) in 25 ml dry THF N-hydroxysuccinimide (1.56 g, 13.6 mmol) was added at 0° C. and the mixture was stirred for 10 minutes. A solution of dicyclohexylcarbodiimide (2.81 g, 13.6 mmol) in 3 ml dry THF was added. The mixture was stirred for 14 h, during which time it was allowed to warm to room temperature. The separated N,N′-dicyclohexylurea was removed by filtration and the solvent was evaporated in vacuo. The residue was twice recrystallized from isopropanol to give the active ester as a white solid (4.47 g, 84%) of m.p. 140° C.—TLC (MeOH/CHCl 3 , 1:50): R f =0.5.— 1 H NMR (400 MHz, DMSO-d 6 ): δ=1.20 (d, 3 H, J=7.0 Hz, CH 3 ), 1.44 (d, 3 H, J=7.4 Hz, CH 3 ), 2.79 (s, 4 H, 2×CH 2 ), 4.04-4.10 (m, 1 H, CH), 4.63-4.69 (m, 1 H, CH), 4.96-5.04 (m, 2 H, CH 2 ), 7.28-7.38 (m, 5 H, aryl-H), 7.45 (d, 1 H, J=7.8 Hz, NH), 8.58 (d, 1 H, J=7.0 Hz, NH).—MS (EI) m/z (%): 392 [M+H + ], 414 [M+Na + ], 430 [M+K + ].
Synthesis of Z-Ala-Ala-Asn(Trt)-OH (2)
[0063] The tripeptide Z-Ala-Ala-Asn(Trt)-OH (2) was prepared according to the following procedure: To a stirred solution of H-Asn(Trt)-OH (4.97 g, 13.28 mmol, obtained from Bachem) in dry DMF (25 ml) a solution of Z-Ala-Ala-OSu (5.2 g, 13.28 mmol) in dry DMF (20 ml) was added and stirred for 14 h at room temperature. The solvent was evaporated in vacuo by using an oil pump. The obtained crude compound was dissolved in ethyl acetate (100 ml), washed with 1 N HCl (2×30 ml) and water (30 ml). The organic layer was dried over Na 2 SO 4 , filtered and concentrated under reduced pressure to give the tripeptide as a white solid (7.95 g, 92%) of m.p. 196° C. The peptide was used without further purification.— 1 H NMR (500 MHz, DMSO-d 6 ): δ=1.18 (d, 3 H, J=7.1 Hz, CH 3 ), 1.22 (d, 3 H, J=7.0 Hz, CH 3 ), 2.62-2.88 (m, 2 H, CHCH 2 ), 4.06-4.12 (m, 1 H, CH), 4.31-4.37 (m, 1 H, CH), 4.46-4.50 (m, 1 H, CH), 4.98-5.04 (m, 2 H, CH 2 O), 7.15-7.35 (m, 20 H, aryl-H).—MS (EI) m/z (%): 651 [M+H + ], 673 [M+Na + ], 689 [M+K + ].
Synthesis of Z-Ala-Ala-Asn(Trt)-N(OCH 3 )CH 3 (3)
[0064] The Weinreb amide Z-Ala-Ala-Asn(Trt)-N(OCH 3 )CH 3 (3) was prepared according to the method of Yasuma, 1998: To a stirred solution of Z-Ala-Ala-Asn(Trt)-OH (0.5 g, 0.77 mmol), N,O-dimethylhydroxylamine hydrochloride (79 mg, 0.81 mmol), and triethylamine (114 μl, 0.82 mmol) in dry DMF (3 ml) were added diisopropylcarbodiimide (131 μl, 0.85 mmol) and HOBt (115 mg, 0.85 mmol) at 0° C., and the whole was stirred for 16 h during which time it was allowed to warm to room temperature. The mixture was concentrated under reduced pressure. The obtained crude compound was dissolved in CH 2 Cl 2 (25 ml) and washed with aqueous citric acid, water, aqueous NaHCO 3 , brine (5 ml per washing step). The organic layer was dried over Na 2 SO 4 , filtered and concentrated under reduced pressure to give the Weinreb amide as a white solid (0.49 g, 92%). The Weinreb amide was used without further purification.—TLC (MeOH/CHCl 3 , 1:30): R f =0.49.— 1 H NMR (400 MHz, CDCl 3 ): δ=1.26 (d, 3 H, J=7.0 Hz, CH 3 ), 1.29 (d, 3 H, J=7.0 Hz, CH 3 ), 2.64-2.76 (m, 2 H, CHCH 2 ), 2.86 (s, 3 H, NCH 3 ), 3.66 (s, 3 H, OCH 3 ), 3.76-3.83 (m, 1 H, CH), 4.07-4.13 (m, 1 H, CH), 4.33-4.40 (m, 1 H, CH), 5.02-5.09 (m, 2 H, CH 2 O), 7.13-7.34 (m, 20 H, aryl-H).—MS (EI) m/z (%): 694 [M+H + ], 716 [M+Na + ], 732 [M+K + ].
Synthesis of Z-Ala-Ala-Asn(Trt)-H (4)
[0065] The aldehyde Z-Ala-Ala-Asn(Trt)-H (4) was prepared according to the method of Fehrentz and Castro, 2000: To a stirred solution of Z-Ala-Ala-Asn(Trt)-N(OCH 3 )CH 3 (1.50 g, 2.16 mmol) in absolute THF (20 ml) was added dropwise lithium aluminium hydride (1.0 M, 2.7 ml, 2.7 mmol) at 0° C. After 15 minutes the mixture was hydrolyzed with aqueous citric acid (10 ml) and after brought to room temperature the solvent was evaporated in vacuo. The mixture was diluted with pH-7 buffer solution (15 ml). The organic material was extracted (5×30 ml) with ethyl acetate. The organic layer was dried over Na 2 SO 4 , filtered and concentrated under reduced pressure to give the aldehyde as a white solid (1.25 g, 91%), which was used without further purification.—TLC (MeOH/CHCl 3 , 1:9): R f =0.64.— 1 H NMR (400 MHz, CDCl 3 ): δ=1.33 (d, 3 H, J=7.0 Hz, CH 3 ), 1.37 (d, 3 H, J=7.2 Hz, CH 3 ), 2.56-2.72 (m, 2 H, CHCH 2 ), 4.08-4.13 (m, 1 H, CH), 4.28-4.34 (m, 1 H, CH), 4.54-4.63 (m, 1 H, CH), 5.04-5.09 (m, 2 H, CH 2 O), 7.24-7.32 (m, 20 H, aryl-H), 9.49 (s, 1 H, aldehyde).—MS (EI) m/z (%): 635 [M+H + ], 657 [M+Na + ], 732 [M+K + ].
Synthesis of tert.-Butyl 2-[2-(Cbz-L-Ala-L-Ala)-hydrazino]acetic acid (14)
[0066] Compound 14 was prepared as follows: To a stirred solution of Z-Ala-Ala-OSu (7.98 g, 20.4 mmol) in dry THF (50 ml) a solution of tert.-Butyl 2-(hydrazino)acetic acid (2.98 g, 20.4 mmol) in dry THF (20 ml) was added and stirred for 14 h at room temperature. The solvent was evaporated in vacuo. The obtained crude compound was triturated with water and filtered. The resulted solid was washed two times with a small amount of water, dried over P 4 O 10 and used without further purification (5.6 g, 65%).—TLC (MeOH/CHCl 3 , 1:9): R f =0.53.— 1 H NMR (400 MHz, CDCl 3 ): δ=1.35 (d, 3 H, J=7.0 Hz, CH 3 ), 1.36 (d, 3 H, J=7.1 Hz, CH 3 ), 1.44 (s, 9 H, t-Bu), 3.73 (s, br., 2 H, NHCH 2 ), 4.20-4.32 (m, 1 H, CH), 4.42-4.50 (m, 1 H, CH), 5.06-5.13 (m, 2 H, CH 2 O), 5.39 (s, br., 1 H, NH), 5.58 (s, br., 1 H, NH), 7.02 (s, br., 1 H, NH), 7.28-7.38 (m, 5 H, aryl-H).—MS (EI) m/z (%): 423 [M+H + ], 445 [M+Na + ], 461 [M+K + ].
Synthesis of 2-[2-(Cbz-L-Ala-L-Ala)-hydrazino]acetic acid (15)
[0067] Compound 15 was prepared as follows: tert.-Butyl 2-[2-(Cbz-L-Ala-L-Ala)-hydrazino]acetic acid (2.5 g, 5.9 mmol) was dissolved in a mixture of trifluoroacetic acid (40 ml), CH 2 Cl 2 (40 ml) and methyl phenyl sulphide (2 ml). This solution was stirred for 2 h at room temperature before it was diluted with toluol. The solvents were removed under reduced pressure and the obtained residue was triturated with Et 2 O and filtered. The resulted solid was washed three times with Et 2 O and dried to give the desired compound as a white solid (1.57 g, 73%), which was used without further purification.—TLC (MeOH/CHCl 3 , 1:9): R f =0.15.— 1 H NMR (200 MHz, DMSO-d 6 ): δ=1.15 (d, 3 H, J=7.0 Hz, CH 3 ), 1.17 (d, 3 H, J=7.0 Hz, CH 3 ), 3.40 (s, 2 H, NHCH 2 ), 3.97-4.11 (m, 1 H, CH), 4.17-4.27 (m, 1 H, CH), 4.94-5.07 (m, 2 H, CH 2 O), 7.26-7.39 (m, 5 H, aryl-H), 7.92 (d, 1 H, J=7.3 Hz, NH), 9.35 (s, br., 1 H, NH).—MS (EI) m/z (%): 367 [M+H + ], 389 [M+Na + ], 405 [M+K + ].
Synthesis of 2-[2-(Cbz-L-Ala-L-Ala)-hydrazino]triphenylmethylacetamide (16)
[0068] Compound 16 was prepared as follows: 2-[2-(Cbz-L-Ala-L-Ala)-hydrazino]acetic acid (0.30 g, 0.82 mmol) was dissolved in dry DMF (5 ml) and cooled to 0° C. with an ice-bath. To this stirred solution were added HATU (0.31 mg, 0.82 mmol), HOAt (0.11 mg, 0.82 mmol), triphenylmethylamine (0.32 g, 0.82 mmol) and N-ethyldiisopropylamine (0.28 ml, 1.64 mmol) and the whole mixture was stirred for 16 h during which time it was allowed to warm to room temperature. The solvent was evaporated in vacuo by using an oil pump. The obtained crude compound was dissolved in ethyl acetate (25 ml), washed with 1 N HCl, water, aqueous NaHCO 3 , and brine (5 ml per washing step). The organic layer was dried over Na 2 SO 4 , filtered and concentrated under reduced pressure. The obtained residue was purified by flash chromatography to give the desired compound as a solid (40 mg, 8%).—TLC (MeOH/CHCl 3 , 1:9): R f =0.15.— 1 H NMR (500 MHz, DMSO-d 6 ): δ=1.15 (d, 3 H, J=7.1 Hz, CH 3 ), 1.16 (d, 3 H, J=7.1 Hz, CH 3 ), 3.42 (s, 2 H, NHCH 2 ), 4.02-4.08 (m, 1 H, CH), 4.19-4.25 (m, 1 H, CH), 4.96-5.03 (m, 2 H, CH 2 O), 7.17-7.42 (m, 20 H, aryl-H), 7.96 (d, 1 H, J=7.3 Hz, NH), 9.68 (s, br., 1 H, NH).—MS (EI) m/z (%): 608 [M+H + ], 630 [M+Na + ], 646 [M+K + ].
Synthesis of 2-[2-(Cbz-L-Ala-L-Ala)-1-(chloroacetyl)hydrazino]triphenylmethylacetamide (17)
[0069] Compound 17 was prepared as follows: To a stirred solution of compound 16 (40 mg, 66 μmol) in dry THF (1.5 ml) at 0° C. was added triethylamine (14 μl, 100 μmol) and chloroacetyl chloride (5.3 μl, 66 μmol). After stirring the mixture for 15 minutes the solvent was removed under reduced pressure. The obtained crude compound was purified by flash chromatography to give the product as a white solid (37 mg, 82%).—TLC (MeOH/CHCl 3 , 1:9): R f =0.26.—MS (EI) m/z (%): 684 [M+H + , 35 Cl], 686 [M+H + , 37 Cl], 706 [M+Na + , 35 Cl], 708 [M+Na + , 37 Cl], 722 [M+K + , 35 Cl], 724 [M+K + , 37 Cl].
Synthesis of Z-Ala-Ala-Asn-OH (19)
[0070] The tripeptide Z-Ala-Ala-Asn-OH (19) was prepared according to the procedure of Method D and was purified by flash chromatography to give the product as a white solid in 88% yield.—TLC (MeOH/CHCl 3 , 1:9): R f =0.10.— 1 H NMR (500 MHz, DMSO-d 6 ): δ=1.18 (d, 3 H, J=7.1 Hz, CH 3 ), 1.20 (d, 3 H, J=7.2 Hz, CH 3 ), 2.45-2.52 (m, 2 H, CHCH 2 ), 4.02-4.09 (m, 1 H, CH), 4.26-4.31 (m, 1 H, CH), 4.47-4.51 (m, 1 H, CH), 4.97-5.04 (m, 2 H, CH 2 O), 6.87 (s, br., 1 H, NH), 7.30-7.37 (m, 5 H, aryl-H), 7.92 (d, 1 H, J=7.3 Hz, NH), 7.98 (d, 1 H, J=7.9 Hz, NH).—MS (EI) m/z (%): 409 [M+H + ], 431 [M+Na + ], 447 [M+K + ].
Synthesis of 2-[2-(Cbz-L-Ala-L-Ala)-1-(bromoacetyl)hydrazino]triphenylmethylacetamide (21)
[0071] Compound 21 was prepared as follows: To a stirred solution of 16 (57 mg, 94 μmol, 1.0 equiv) in dry THF (3 ml) at 0° C. was added triethylamine (20.0 μl, 140 μmol, 1.5 equiv) and bromoacetyl bromide (8.2 μmol, 94 μmol, 1.0 equiv). After stirring the mixture for 15 min, the solvent was removed under reduced pressure. The obtained crude compound was purified by flash chromatography, generating the product (55 mg, 80%) as a white solid of m.p. 93-100° C.—TLC (MeOH/CHCl 3 , 1:9): R f =0.68.— 1 H NMR (400 MHz, DMSO-d 6 ): δ=1.16 (d, 3 H, J=7.0 Hz, CH 3 ), 1.23 (d, 3 H, J=7.4 Hz, CH 3 ), 4.04-4.10 (m, 1 H, CH), 4.13-4.18 (m, 1 H, CH), 4.25 [s, 2 H, C(O)CH 2 Br], 4.29 (s, 2 H, NHCH 2 ), 4.94-5.03 (m, 2 H, CH 2 O), 7.15-7.34 (m, 20 H, aryl-H), 7.43 (d, 1 H, J=7.4 Hz, NH), 8.17 (d, 1 H, J=8.6 Hz, NH), 8.92 (s, 1 H, NH), 10.71 (s, br., 1 H, NH).—MS (EI) m/z (%): 728 [M+H + , 79 Br], 730 [M+H + , 81 Br], 750 [M+Na + , 79 Br], 752 [M+Na + , 81 Br], 766 [M+K + , 79 Br], 768 [M+K + , 81 Br].
Synthesis of 2-[2-(Cbz-L-Ala-L-Ala)-1-(benzoyloxyacetyl)hydrazino]triphenylmethyl-acetamide (23)
[0072] Compound 23 was prepared as follows: Dry KF (15 mg, 257 μmol, 2.5 equiv) was added to a stirred solution of 21 (75 mg, 103 μmol, 1.0 equiv) in dry DMF (4 ml) at room temperature. After stirring the mixture for 3 min, benzoic acid was added (15 mg, 123 μmol, 1.2 equiv) and the whole mixture was stirred for 16 h. The solvent was evaporated under vacuum by using an oil pump. The obtained crude compound (80 mg, 100% crude yield) was used without further purification.—TLC (MeOH/CHCl 3 , 1:9): R f =0.44.—MS (EI) m/z (%): 770 [M+H + ], 792 [M+Na + ], 808 [M+K + ].
[0000] Pharmaceutical Compositions
[0073] Additionally, the present invention includes the use of such a compound for the preparation of a medicament for the treatment of a condition mediated by modulation of the legumain activity in a subject. The compound may be administered to a patient by any conventional route of administration, including, but not limited to, intravenous, oral, subcutaneous, intramuscular, intradermal and parenteral.
[0074] The present invention also provides pharmaceutical compositions comprising one or more compounds of this invention in association with a pharmaceutically active carrier.
[0075] To prepare the pharmaceutical compositions of this invention, one or more active compounds or salts thereof of the invention as the active ingredient, is intimately admixed with a pharmaceutical carrier according to conventional pharmaceutical compounding techniques, which carrier may take a wide variety of forms depending of the form of preparation desired for administration, e.g., oral or parenteral such as intramuscular. In preparing the compositions in oral dosage form, any of the usual pharmaceutical media may be employed. Thus, for liquid oral preparations, such as for example, suspensions, elixirs and solutions, suitable carriers and additives include water, glycols, oils, alcohols, flavoring agents, preservatives, coloring agents and the like; for solid oral preparations such as, for example, powders, capsules, gelcaps and tablets, suitable carriers and additives include starches, sugars, diluents, granulating agents, lubricants, binders, disintegrating agents and the like. Because of their ease in administration, tablets and capsules represent the most advantageous oral dosage unit form, in which case solid pharmaceutical carriers are obviously employed. If desired, tablets may be sugar coated or enteric coated by standard techniques. For parenterals, the carrier will usually comprise sterile water, through other ingredients, for example, for purposes such as aiding solubility or for preservation, may be included.
[0076] Injectable suspensions may also prepared, in which case appropriate liquid carriers, suspending agents and the like may be employed. The pharmaceutical compositions herein will contain, per dosage unit, e.g., tablet, capsule, powder, injection, teaspoonful and the like, an amount of the active ingredient necessary to deliver an effective dose as described above. The pharmaceutical compositions herein will contain, per unit dosage unit, e.g., tablet, capsule, powder, injection, suppository, teaspoonful and the like, of from about 0.03 mg to 100 mg/kg (preferred 0.1-30 mg/kg) and may be given at a dosage of from about 0.1-300 mg/kg/day (preferred 1-50 mg/kg/day). The dosages, however, may be varied depending upon the requirement of the patients, the severity of the condition being treated and the compound being employed. The use of either daily administration or post-periodic dosing may be employed.
[0077] Preferably these compositions are in unit dosage forms from such as tablets, pills, capsules, powders, granules, sterile parenteral solutions or suspensions, metered aerosol or liquid sprays, drops, ampoules, autoinjector devices or suppositories; for oral parenteral, intranasal, sublingual or rectal administration, or for administration by inhalation or insufflation. Alternatively, the composition may be presented in a form suitable for once-weekly or once-monthly administration; for example, an insoluble salt of the active compound, such as the decanoate salt, may be adapted to provide a depot preparation for intramuscular injection. For preparing solid compositions such as tablets, the principal active ingredient is mixed with a pharmaceutical carrier, e.g. conventional tableting ingredients such as corn starch, lactose, sucrose, sorbitol, talc, stearic acid, magnesium stearate, dicalcium phosphate or gums, and other pharmaceutical diluents, e.g. water, to form a solid preformulation composition containing a homogeneous mixture of a compound of the present invention, or a pharmaceutically acceptable salt thereof. When referring to these preformulation compositions as homogeneous, it is meant that the active ingredient is dispersed evenly throughout the composition so that the composition may be readily subdivided into equally effective dosage forms such as tablets, pills and capsules. This solid preformulation composition is then subdivided into unit dosage forms of the type described above containing from 0.01 to about 500 mg of the active ingredient of the present invention.
[0078] The tablets or pills of the novel composition can be coated or otherwise compounded to provide a dosage form affording the advantage of prolonged action. For example, the tablet or pill can comprise an inner dosage and an outer dosage component, the latter being in the form of an envelope over the former. The two components can be separated by an enteric layer which serves to resist disintegration in the stomach and permits the inner component to pass intact into the duodenum or to be delayed in release. A variety of material can be used for such enteric layers or coatings, such materials including a number of polymeric acids with such materials as shellac, cetyl alcohol and cellulose acetate.
[0079] This liquid forms in which the novel compositions of the present invention may be incorporated for administration orally or by injection include, aqueous solutions, suitably flavored syrups, aqueous or oil suspensions, and flavored emulsions with edible oils such as cottonseed oil, sesame oil, coconut oil or peanut oil, as well as elixirs and similar pharmaceutical vehicles. Suitable dispersing or suspending agents for aqueous suspensions, include synthetic and natural gums such as tragacanth, acacia, alginate, dextran, sodium carboxymethylcellulose, methylcellulose, polyvinylpyrrolidone or gelatin.
[0080] Where the processes for the preparation of the compounds according to the invention give rise to mixture of stereoisomers, these isomers may be separated by conventional techniques such as preparative chromatography. The compounds may be prepared in racemic form, or individual enantiomers may be prepared either by enantiospecific synthesis or by resolution. The compounds may, for example, be resolved into their components enantiomers by standard techniques, such as the formation of diastereomeric pairs by salt formation with an optically active acid, such as (−)-di-p-toluoyl-d-tartaric acid and/or (+)-di-p-toluoyl-l-tartaric acid followed by fractional crystallization and regeneration of the free base. The compounds may also resolved by formation of diastereomeric esters or amides, followed by chromatographic separation and removal of the chiral auxiliary. Alternatively, the compounds may be resolved using a chiral HPLC column.
[0081] During any of the processes for preparation of the compounds of the present invention, it may be necessary and/or desirable to protect sensitive or reactive groups on any of the molecules concerned. This may be achieved by means of conventional protecting groups, such as those described in Protective Groups in Organic Chemistry , ed. J. F. W. McOmie, Plenum Press, 1973; and T. W. Greene & P. G. M. Wuts, Protective Groups in Organic Synthesis , John Wiley & Sons, 1991. The protecting groups may be removed at a convenient subsequent stage using methods known from the art.
[0082] The method of treating conditions modulated by legumain described in the present invention may also be carried out using a pharmaceutical composition comprising any of the compounds as defined herein and a pharmaceutically acceptable carrier. The pharmaceutical composition may contain between about 0.01 mg and 500 mg, preferably about 5 to 50 mg, of the compound, and may be constituted into any form suitable for the mode of administration selected. Carriers include necessary and inert pharmaceutical excipients, including, but not limited to, binders, suspending agents, lubricants, flavorants, sweeteners, preservatives, dyes, and coatings. Compositions suitable for oral administration include solid forms, such as pills, tablets, caplets, capsules (each including immediate release, timed release and sustained release formulations), granules, and powders, and liquid forms, such as solutions, syrups, elixirs, emulsions, and suspensions. Forms useful for parenteral administration include sterile solutions, emulsions and suspensions.
[0083] Advantageously, compounds of the present invention may be administered in a single daily dose, or the total daily dosage may be administered in divided doses of two, three or four times daily. Furthermore, compounds for the present invention can be administered in intranasal form via topical use of suitable intranasal vehicles, or via transdermal skin patches well known to those of ordinary skill in that art. To be administered in the form of transdermal delivery system, the dosage administration will, of course, be continuous rather than intermittent throughout the dosage regimen.
[0084] For instance, for oral administration in the form of a tablet or capsule, the active drug component can be combined with an oral, non-toxic pharmaceutically acceptable inert carrier such as ethanol, glycerol, water and the like. Moreover, when desired or necessary, suitable binders; lubricants, disintegrating agents and coloring agents can also be incorporated into the mixture. Suitable binders include, without limitation, starch, gelatin, natural sugars such as glucose or betalactose, corn sweeteners, natural and synthetic gums such as acacia, tragacanth or sodium oleate, sodium stearate, magnesium stearate, sodium benzoate, sodium acetate, sodium chloride and the like. Disintegrators include, without limitation, starch, methyl cellulose, agar, bentonite, xanthan gum and the like.
[0085] The liquid forms in suitable flavored suspending or dispersing agents such as the synthetic and natural gums, for example, tragacanth, acacia, methyl-cellulose and the like. For parenteral administration, sterile suspensions and solutions are desired. Isotonic, preparations which generally contain suitable preservatives are employed when intravenous administration is desired.
[0086] The compound of the present invention can also be administered in the form of liposome delivery systems, such as small unilamellar vesicles, large unilamellar vesicles, and multilamellar vesicles. Liposomes can be formed from a variety of phospholipids, such as cholesterol, stearylamine or phosphatidylcholines.
[0087] Compounds of the present invention may also be delivered by the use of monoclonal antibodies as individual carriers to which the compound molecules are coupled. The compounds of the present invention may also be coupled with soluble polymers as targetable drug carriers. Such polymers can include polyvinylpyrrolidone, pyran copolymer, polyhydroxypropylmethacrylamidephenol, olyhydroxyethylaspartamidephenol, or polyethyleneoxidepolyllysine substituted with palmitoyl residue. Furthermore, the compounds of the present invention may be coupled to a class of biodegradable polymers useful in achieving controlled release of a drug, for example, polyactic acid, polyepsilon caprolactone, polyhydroxy butyeric acid, polyorthoesters, polyacetals, polydihydropyrans, polycyanoacrylates and cross-linked or amphipathic block copolymers of hydrogels.
[0088] Compounds of this invention may be administered in any of the foregoing compositions and according to dosage regimens established in the art whenever treatment of the addressed disorders is required.
[0089] The daily dosage of the products may be varied over a wide range from 0.01 to 1.000 mg per adult human per day. For oral administration, the compositions are preferably provided in the form of tablets containing, 0.01, 0.05, 0.1, 0.5, 1.0, 2.5, 5.0, 10.0, 15.0, 25.0, 50.0, 100, 150, 200, 250 and 500 milligrams of the active ingredient for the symptomatic adjustment of the dosage to the patient to be treated. An effective amount of the drug is ordinarily supplied at a dosage level of from about 0.1 mg/kg to about 300 mg/kg of body weight per day. Preferably, the range is from about 1 to about 50 mg/kg of body weight per day. The compounds may be administered on a regimen of 1 to 4 times per day.
[0090] Optimal dosages to be administered may be readily determined by those skilled in the art, and will vary with the particular compound used, the mode of administration, the strength of the preparation, the mode of administration, and the advancement of disease condition. In addition, factors associated with the particular patient being treated, including patient age, weight, diet and time of administration, will result in the need to adjust dosages.
[0091] The compounds or compositions of the present invention may be taken before a meal, while taking a meal or after a meal.
[0092] When taken before a meal, the compounds or compositions of the present invention can be taken 1 hour, preferably 30 or even 15 or 5 minutes before eating.
[0093] When taken while eating, the compounds or compositions of the present invention can be mixed into the meal or taken in a separate dosage form as described above.
[0094] When taken after a meal, the compounds and compositions of the present invention can be taken 5, 15, or 30 minutes or even 1 hour after finishing a meal.
EXAMPLES
Example 1
Synthesis of Methyl (S)-(E)-4-[Cbz-L-Ala-L-Ala]amino-6-amino-6-oxo-2-hexenoate (5)
[0095] This compound was prepared starting from the aldehyde using the Horner-Emmons reaction (Method B) with sodium bis(trimethylsilyl)amide and trimethyl phophonoacatate followed by deprotecting the trityl protecting (Method D). The crude compound was purified by preparative HPLC to give the product as a white solid (43%) of m.p. 242° C.—TLC (MeOH/CHCl 3 , 1:9): R f =0.34.— 1 H NMR (400 MHz, DMSO-d 6 ): δ=1.20 (d, 3 H, J=7.1 Hz, CH 3 ), 1.22 (d, 3 H, J=7.1 Hz, CH 3 ), 2.38 (d, 2 H, J=6.8 Hz, CHCH 2 ), 3.64 (s, 3 H, OCH 3 ), 4.01-4.14 (m, 1 H, CH), 4.16-4.25 (m, 1 H, CH), 4.73-4.75 (m, 1 H, CH), 4.96-5.05 (m, 2 H, CH 2 O), 5.80 (d, 1 H, J=15.8 Hz, COCH═CH), 6.82 (dd, 1 H, J=15.8 Hz, J=4.8 Hz, COCH═CH), 6.94 (s, br., 1 H, NH), 7.30-7.34 (m, 5 H, aryl-H), 7.46 (d, 1 H, J=7.2 Hz, NH), 8.01 (d, 1 H, J=7.4 Hz, NH), 8.08 (d, 1 H, J=8.0 Hz, NH).— 13 C NMR (100 MHz, DMSO-d 6 ): δ=17.89, 18.12 (CH 3 ), 46.64, 48.26, 50.03 (CH), 51.34 (OCH 3 ), 65.37 (CH 2 C 6 H 5 ), 119.70 (COCH═CH), 127.79, 127.85, 128.41, 137.12 (aryl-C), 148.45 (COCH═CH), 155.91, 166.14, 171.31, 171.63, 172.46 (C═O).—MS (EI) m/z (%): 449 [M+H + ], 471 [M+Na + ], 487 [M+K + ].
Example 2
Synthesis of Ethyl (S)-(E)-4-[Cbz-L-Ala-L-Ala]amino-6-amino-6-oxo-2-hexenoate (6)
[0096] This compound was prepared starting from the aldehyde using the Horner-Emmons reaction (Method B) with sodium bis(trimethylsilyl)amide and triethyl phophonoacatate followed by deprotecting the trityl protecting (Method D). The crude compound was purified by preparative HPLC to give the product as a white solid (56%) of m.p. 194-196° C.—TLC (MeOH/CHCl 3 , 1:9): R f =0.38.— 1 H NMR (400 MHz, CD 3 OD): δ=1.25 (t, 3 H, J=7.1 Hz, CH 3 ), 1.35 (d, 3 H, J=7.1 Hz, CH 3 ), 1.38 (d, 3 H, J=7.1 Hz, CH 3 ), 2.55 (d, 2 H, J=6.7 Hz, CHCH 2 ), 4.08-4.14 (m, 1 H, CH), 4.16 (q, 2 H, J=7.1 Hz, CH 2 CH 3 ), 4.30-4.36 (m, 1 H, CH), 4.86-4.88 (m, 1H, CH), 5.06-5.12 (m, 2 H, CH 2 O), 5.94 (d, 1 H, J=15.7 Hz, COCH═CH), 6.89 (dd, 1 H, J=15.7 Hz, J=5.1 Hz, COCH═CH), 7.27-7.37 (m, 5 H, aryl-H).—MS (EI) m/z (%): 463 [M+H + ], 485 [M+Na + ], 501 [M+K + ].
Example 3
Synthesis of Allyl (S)-(E)-4-[Cbz-L-Ala-L-Ala]amino-6-amino-6-oxo-2-hexenoate (7)
[0097] This compound was prepared starting from the aldehyde using the Wittig reaction (Method A) with allyl (triphenylphophoranylidene)acetate and deprotecting the trityl protecting (Method D). The crude compound was purified by preparative HPLC to give the product as a white solid (62%) of m.p. 182-184° C.—TLC (MeOH/CHCl 3 , 1:9): R f =0.41.— 1 H NMR (400 MHz, DMSO-d 6 ): δ=1.21 (t, 3 H, J=7.0 Hz, CH 3 ), 1.22 (d, 3 H, J=7.0 Hz, CH 3 ), 2.55 (d, 2 H, J=6.8 Hz, CHCH 2 ), 4.01-4.06 (m, 1 H, CH), 4.20-4.26 (m, 1 H, CH), 4.59 (d, 2 H, J=5.3 Hz, CH 2 CH═CH 2 ), 4.73-4.76 (m, 1 H, CH), 4.98-5.05 (m, 2 H, CH 2 O), 5.19-5.32 (m, 2 H, CH 2 CH═CH 2 ), 5.82 (d, 1 H, J=15.7 Hz, COCH═CH), 5.88-5.97 (m, 1 H, CH 2 CH═CH 2 ), 6.86 (dd, 1 H, J=15.7 Hz, J=4.7 Hz, COCH═CH), 6.95 (s, br., 1 H, NH), 7.30-7.42 (m, 5 H, aryl-H), 7.46 (d, 1 H, J=7.4 Hz, NH), 8.01 (d, 1 H, J=7.2 Hz, NH), 8.09 (d, 1 H, J=8.2 Hz, NH).—MS (EI) m/z (%): 475 [M+H + ], 492 [M+NH 4 + ], 497 [M+Na + ], 513 [M+K + ].
Example 4
Synthesis of (S)-(E)-4-[Cbz-L-Ala-L-Ala]amino-6-amino-6-oxo-2-hexenoic acid (8)
[0098] This compound was prepared starting from the aldehyde using the Horner-Emmons reaction (Method B) with sodium bis(trimethylsilyl)amide and triethyl phophonoacatate. The saponification was carried out as described in Method E. The trityl protecting group was removed by TFA in the presence of triisopropylsilane (Method D). The crude compound was purified by preparative HPLC to give the product as a white solid (37%) of m.p. 205-208° C.—TLC (MeOH/CHCl 3 , 1:9): R f =0.19.— 1 H NMR (400 MHz, CD 3 OD): δ=1.34 (t, 3 H, J=6.8 Hz, CH 3 ), 1.37 (d, 3 H, J=6.8 Hz, CH 3 ), 2.55 (d, 2 H, J=6.8 Hz, CHCH 2 ), 4.10-4.14 (m, 1 H, CH), 4.31-4.36 (m, 1 H, CH), 4.84-4.88 (m, 1 H, CH), 5.04-5.11 (m, 2 H, CH 2 O), 5.92 (d, 1 H, J=15.7 Hz, COCH═CH), 6.88 (dd, 1 H, J=15.7 Hz, J=5.1 Hz, COCH═CH), 7.28-7.35 (m, 5 H, aryl-H).—MS (EI) m/z (%): 435 [M+H + ], 457 [M+Na + ], 473 [M+K + ].
Example 5
Synthesis of Methyl (S)-(E)-4-[Cbz-L-Ala-L-Ala]amino-6-amino-2-methyl-6-oxo-2-hexenoate (9)
[0099] This compound was prepared starting from the aldehyde using Wittig reaction (Method A) with (carbethoxyethylidene)triphenylphophorane. The saponification was carried out as described in Method E and the carbonic acid was esterificated as described in Method F. The trityl protecting group was removed by TFA in the presence of triisopropylsilane (Method D). The crude compound was purified by preparative HPLC to give the product as a white solid (65%) of m.p. 188-191° C.—TLC (MeOH/CHCl 3 , 1:9): R f =0.54.— 1 H NMR (400 MHz, CD 3 OD): δ=1.33 (t, 3 H, J=7.1 Hz, CH 3 ), 1.34 (d, 3 H, J=7.1 Hz, CH 3 ), 1.91 (d, 3 H, J=1.4 Hz, COCCH 3 ═CH) 2.43-2.57 (m, 2 H, CHCH 2 ), 4.06-4.10 (m, 1 H, CH), 4.27-4.29 (m, 1 H, CH), 5.01-5.06 (m, 1 H, CH), 5.07-5.15 (m, 2 H, CH 2 O), 6.61 (dd, 1 H, J=9.0 Hz, J=1.4 Hz, COCCH 3 ═CH), 7.29-7.38 (m, 5 H, aryl-H).—MS (EI) m/z (%): 463 [M+H + ], 485 [M+Na + ], 501 [M+K + ].
Example 6
Synthesis of Ethyl (S)-(E)-4-[Cbz-L-Ala-L-Ala]amino-6-amino-2-methyl-6-oxo-2-hexenoate (10)
[0100] This compound was prepared starting from the aldehyde using Wittig reaction (Method A) with (carbethoxyethylidene)triphenylphophorane. The isolated crude product was deprotected by TFA in the presence of triisopropylsilane (Method D). The crude compound was purified by preparative HPLC to give the product as a white solid (64%) of m.p. 200-204° C.—TLC (MeOH/CHCl 3 , 1:9): R f =0.33.— 1 H NMR (400 MHz, DMSO-d 6 ): δ=1.15-1.21 (m, 9 H, 3×CH 3 ), 1.80 (d, 3 H, J=1.2 Hz, COCCH 3 ═CH), 2.31-2.35 (m, 2 H, CHCH 2 ), 4.02-4.08 (m, 1 H, CH), 4.10 (q, 2 H, CH 2 CH 3 ), 4.15-4.21 (m, 1 H, CH), 4.83-4.87 (m, 1 H, CH), 4.97-5.05 (m, 2 H, CH 2 O), 6.46 (dd, 1 H, J=9.0 Hz, J=1.4 Hz, COCCH 3 ═CH), 6.86 (s, 1 H, NH), 7.30-7.35 (m, 5 H, aryl-H), 7.44 (d, 1 H, J=7.2 Hz, NH), 7.93 (d, 1 H, J=7.4 Hz, NH), 8.05 (d, 1 H, J=7.4 Hz, NH).—MS (EI) m/z (%): 477 [M+H + ], 499 [M+Na + ], 515 [M+K + ].
Example 7
Synthesis of (S)-(E)-4-[Cbz-L-Ala-L-Ala]amino-6-amino-2-methyl-6-oxo-2-hexenoic acid (11)
[0101] This compound was prepared starting from the aldehyde using Wittig reaction (Method A) with (carbethoxyethylidene)triphenylphophorane. The saponification was carried out as described in Method E. The trityl protecting group was removed by TFA in the presence of triisopropylsilane (Method D). The crude compound was purified by preparative HPLC to give the product as a white solid (32%) of m.p. 185-189° C.—TLC (MeOH/CHCl 3 , 1:9): R f =0.08.— 1 H NMR (400 MHz, CD 3 OD): δ=1.33 (t, 3 H, J=7.1 Hz, CH 3 ), 1.34 (d, 3 H, J=7.1 Hz, CH 3 ), 1.89 (d, 3 H, J=1.2 Hz, COCCH 3 ═CH), 2.42-2.58 (m, 2 H, CHCH 2 ), 4.07-4.10 (m, 1 H, CH), 4.28-4.31 (m, 1 H, CH), 5.00-5.06 (m, 1 H, CH), 5.12-5.16 (m, 2 H, CH 2 O), 6.63 (dd, 1 H, J=9.0 Hz, J=1.2 Hz, COCCH 3 ═CH), 7.26-7.38 (m, 5 H, aryl-H).—MS (EI) m/z (%): 449 [M+H + ], 471 [M+Na + ], 487 [M+K + ].
Example 8
Synthesis of Methyl [(S)-(E)-3-[Cbz-L-Ala-L-Ala]amino-5-amino-5-oxo-1-petene]-sulfonate (12)
[0102] This compound was prepared starting from the aldehyde using the Horner-Emmons reaction (Method C) with sodium hydride and dimethyl methylsulfonomethanephosphonate 14 followed by deprotecting the trityl protecting (Method D). The crude compound was purified by preparative HPLC to give the product as a white solid (71%) of m.p. 193-195° C.—TLC (MeOH/CHCl 3 , 1:9): R f =0.13.— 1 H NMR (400 MHz, CD 3 OD): δ=1.34 (t,3H, J=7.2 Hz, CH 3 ), 1.38 (d, 3 H, J=7.2 Hz, CH 3 ), 2.58-2.61 (m, 2 H, CHCH 2 ), 2.92 (s, 3 H, SO 2 CH 3 ), 4.09-4.16 (m, 1 H, CH), 4.24-4.34 (m, 1 H, CH), 5.04-5.17 (m, 3 H, CH, CH 2 O), 6.68 (d, 1 H, J=15.2 Hz, COCH═CH), 6.85 (dd, 1 H, J=15.2 Hz, J=4.3 Hz, COCH═CH), 7.27-7.35 (m, 5 H, aryl-H).—MS (EI) m/z (%): 469 [M+H + ], 491 [M+Na + ], 507 [M+K + ].
Example 9
Synthesis of Diethyl [(S)-(E)-3-[Cbz-L-Ala-L-Ala]amino-5-amino-5-oxo-1-petenylphosphate (13)
[0103] This compound was prepared starting from the aldehyde using the Horner-Emmons reaction (Method C) with sodium hydride and tetraethyl methylendiphosphonate followed by deprotecting the trityl protecting (Method D). The crude compound was purified by preparative HPLC to give the product as a white solid (60%) of m.p. 95-97° C.—TLC (MeOH/CHCl 3 , 1:9): R f =0.32.— 1 H NMR (400 MHz, CD 3 OD): δ=1.26-1.38 (m, 12 H, 2×CH 2 CH 3 , 2×CHCH 3 ), 2.51-2.61 (m, 2 H, CHCH 2 ), 3.98-4.15 (m, 5 H, CH, 2×CH 2 CH 3 ), 4.28-4.34 (m, 1 H, CH), 5.04-5.15 (m, 3 H, CH, CH 2 O), 5.91 (dd, 1 H, J=35.4 Hz, J=17.4 Hz, COCH═CH), 6.85 (ddd, 1 H, J=21.9 Hz, J=17.6 Hz, J=4.5 Hz, COCH═CH), 7.28-7.37 (m, 5 H, aryl-H).—MS (EI) m/z (%): 527 [M+H + ], 549 [M+Na + ], 565 [M+K + ].
Example 10
Synthesis of 2-[2-(Cbz-L-Ala-L-Ala)-1-(chloroacetyl)hydrazino]acetamide (18)
[0104] The compound 18 was prepared starting from compound 17 (0.054 mmol) by deprotecting the trityl protecting (Method D). The crude compound was purified by preparative HPLC to give the product as a white solid (14 mg, 56%).—TLC (MeOH/CHCl 3 , 1:9): R f =0.20.— 1 H NMR (500 MHz, DMSO-d 6 ): δ=1.18 (d, 3 H, J=6.8 Hz, CH 3 ), 1.23 (d, 3 H, J=6.8 Hz, CH 3 ), 4.02-4.08 (m, 1 H, CH), 4.15-4.23 (m, 1 H, CH), 4.40 (s, br., 2 H, NHCH 2 ), 4.96-5.03 (m, 2 H, CH 2 O), 7.20 (s, 1 H, NH), 7.28-7.37 (m, 5 H, aryl-H), 7.47 (d, 1 H, J=7.3 Hz, NH), 8.22 (s, br., 1 H, NH), 10.58 (s, br, 1 H, NH).—MS (EI) m/z (%): 442 [M+H + ], 35 Cl], 444 [M+H + , 37 Cl], 464 [M+Na + , 35 Cl], 466 [M+Na + , 37 Cl], 480 [M+K + , 35 Cl], 482 [M+K + , 37 Cl].
Example 11
Synthesis of [Cbz-L-Ala-L-Ala-L-Asn]-O-benzoylhydroxamate (20)
[0105] To a solution of O-Benzoylhydroxylamine hydrochloride (85 mg, 0.49 mmol, prepared as described in the procedure of Carpino et al., 1959) in water (5 ml) was added at room temperature a 1 M solution of sodium bicarbonate until the effervescence ended. The organic material was extracted three times with CH 2 Cl 2 (10 ml per extraction). The combined organic layers were dried over Na 2 SO 4 and concentrated under reduced pressure to give O-Benzoylhydroxylamine (49 mg, 73%). In a second flask Z-Ala-Ala-Asn-OH (19) (130 mg, 0.318 mmol) was dissolved in a mixture of dry THF (5 ml) and dry DMF (3 ml). To this stirred solution were added isobutyl chloroformate (41 μl, 0.318 mmol) and NMM (35 μl, 0.318 mmol) at −15° C. After stirring for 15 minutes O-Benzoylhydroxylamine in dry THF (2 ml) was added and the mixture was stirred 14 h, during which time it was allowed to warm to room temperature. The solvent was evaporated in vacuo and the obtained residue was washed with cold KHSO 4 (5% in water, 5 ml). The precipitate was dissolved in ethyl acetate (10 ml), washed with water (3×5 ml) and dried over Na 2 SO 4 . After filtration the solvent was evaporated under reduced pressure. The crude compound was purified by preparative HPLC to give the product as an oil (77 mg, 46%).—TLC (MeOH/CHCl 3 , 1:9): R f =0.31.— 1 H NMR (500 MHz, DMSO-d 6 ): δ=1.19 (d, 3 H, J=6.9 Hz, CH 3 ), 1.21 (d, 3 H, J=7.0 Hz, CH 3 ), 2.78-2.96 (m, 2 H, CHCH 2 ), 4.04-4.08 (m, 1 H, CH), 4.25-4.34 (m, 1 H, CH), 4.48-4.55 (m, 1 H, CH), 4.97-5.04 (m, 2 H, CH 2 O), 7.26-7.42 (m, 10 H, aryl-H), 7.93 (d, 2 H, J=8.2 Hz, NH).—MS (EI) m/z (%): 528 [M+H + ], 550 [M+Na + ], 566 [M+K + ].
Example 12
Synthesis of 2-[2-(Cbz-L-Ala-L-Ala)-1-(bromoacetyl)hydrazino]acetamide (22)
[0106] Compound 22 was prepared starting from 21 (55 mg, 76 μmol) by the cleavage of the trityl protecting group. The crude compound was purified by preparative HPLC, generating the product (20 mg, 54%) as a white solid.—TLC (MeOH/CHCl 3 , 1:50): R f =0.22.— 1 H NMR (500 MHz, DMSO-d 6 ): δ=1.18 (d, 3 H, J=7.0 Hz, CH 3 ), 1.24 (d, 3 H, J=7.0 Hz, CH 3 ), 4.00-4.10 (m, 1 H, CH), 4.08-4.12 (m, 1 H, CH), 4.26 [s, br., 2 H, C(O)CH 2 Br], 4.38 (s, br., 2 H, NHCH 2 ), 4.96-5.03 (m, 2 H, CH 2 O), 7.16 (s, 1 H, NH), 7.29-7.37 (m, 5 H, aryl-H), 7.43 (d, 1 H, J=7.3 Hz, NH), 8.18 (d, J=7.3 Hz, 1 H, NH), 10.59 (s, br., 1 H, NH).—MS (EI) m/z (%): 486 [M+H + , 79 Br], 488 [M+H + , 81 Br], 508 [M+Na + , 79 Br], 510 [M+Na + , 81 Br], 524 [M+K + , 79 Br], 526 [M+K + , 81 Br].
Example 13
Synthesis of 2-[2-(Cbz-L-Ala-L-Ala)-1-(benzoyloxyacetyl)hydrazino]acetamide (24)
[0107] Compound 24 was prepared starting from 23 (80 mg, 103 μmol) by the cleavage of the trityl protecting group. The crude compound was purified by preparative HPLC, generating the product as a white solid (8.7 mg, 16%).—TLC (MeOH/CHCl 3 , 1:9): R f =0.24.— 1 H NMR (400 MHz, DMSO-d6): δ=1.20 (d, 3 H, J=7.1 Hz, CH 3 ), 1.27 (d, 3 H, J=7.1 Hz, CH 3 ), 4.04-4.10 (m, 1 H, CH), 4.21-4.26 (m, 1 H, CH), 4.38 (s, br., 2 H, NHCH 2 ), 4.78 [s, br., 2 H, C(O)CH 2 O], 4.95-5.03 (m, 2 H, CH 2 O), 7.18 (s, 1 H, NH), 7.28-7.36 (m, 4 H, aryl-H), 7.43 (d, 1 H, J=7.6 Hz, NH), 7.50-7.56 (m, 3 H, aryl-H), 7.65-7.70 (m, 1 H, aryl-H), 7.97-7.99 (m, 2 H, aryl-H), 8.22 (s, br., 1 H, NH), 10.60 (s, br., 1 H, NH).—MS (EI) m/z (%): 528 [M+H + ], 545 [M+NH 4 + ], 550 [M+Na + ], 566 [M+K + ].
Example 13
Biological Evaluation
[0108] Fluorogenic Assay:
[0109] The legumain activity was determined in a fluorogenic continuos rate assay using the substrate Z-Ala-Ala-Asn-AMC on a Kontron spectrofluorometer SFM25 (exitation 380; emission 460) equipped with a four cell changer and controlled by an IBM-compatible personal computer. The obtained data were analyzed with the software FLUCOL (38) . The assay were done at 37° C. or 30° C., using a sodium citrate buffer (39.5 mM citric acid/121 mM Na 2 HPO 4 ) containing 1 mM dithiothreitol and 1 mM EDTA. Additionally, 0.1% (w/v) Chaps or 0.015% (w/v) Brij 35 was added.
[0110] The inhibition progress curves were analyzed using non-linear curve fitting software Prism Graph Pad to compute the k obs values. Approximate second-order inactivation constants (k obs /[I]) were calculated for all compounds.
Example 14
Determination of k j -Values
[0111] 100 μl inhibitor stock solution were mixed with 100 μl buffer (HEPES pH 7.6) and 50 μl substrate Z-Ala-Ala-Asn-AMC and preincubated at 30° C. Reaction was started by addition of 20 μl enzyme solution. Formation of the product AMC was measured on a Kontron spectrofluorometer SFM25 (exitation 380; emission 460) and slopes were calculated. Legumain activity was measured at final substrate concentrations of 0.05, 0.1, 0.2, and 0.4 mM and further 7 inhibitor concentrations covering the IC 50 concentration. Calculations were performed using the GraFit 4.0.13 (Erithacus) Software. | Presented are compounds represented by the following general formulas (I) and (II), for inhibiting cysteine protease legumain for modulating associated disease states in subjects. | 0 |
CROSS-REFERENCE
This application is a continuation-in-part of my copending application Ser. No. 918,515 filed June 23, 1978, which in turn was a continuation-in-part of my earlier filed application Ser. No. 780,670 filed Mar. 23, 1977, now abandoned, which in turn was a continuation-in-part of my earlier application Ser. No. 761,414 filed Jan. 27, 1977, now abandoned.
BACKGROUND OF THE INVENTION
Sand used in foundry casting operations is a matter of some expense in the foundry process, particularly in the usual case where additives are included in the sand to make it more adaptable for the intended purpose. For this reason, it is desirable to reuse the sand in subsequent casting operations, and most desirable to prepare the sand for reuse without losing or destroying the relatively expensive additional materials which are included in the sand.
When sand is removed from the flask or mold in which the casting has been poured, it is quite hot and if merely piled on the floor and left to cool, a great deal of floor space would be required inasmuch as the middle of the pile would cool very slowly.
If sand is cooled by subjecting it to a blast or flow of cool air, cooling can be effected but a great deal of the fine additive material will be carried off in the airstream. This results in a requirement for a large bag room, i.e., an enclosure containing a large bag through which the air may pass but which tends to block passage of the fine particles. This is not only expensive, it also results in the loss of the fine additive materials from the foundry sand mix.
SUMMARY OF THE INVENTION
Foundry sand coming directly from a metal pouring operation is very hot, in fact so hot as to normally assure that no moisture is present in the sand. After the sand has been separated from the mold or flask and the casting itself, it still is quite hot and it is desirable that the sand be cooled without loss of fine additives so that it can be reused in a relatively short time. It is also preferable that a continuous method of cooling sand, preparing it for reuse, be provided. The apparatus and method of the present invention fulfill the foregoing requirements by providing an arrangement wherein the Btu content of the hot foundry sand to be cooled is measured and water is added at a specified ratio depending upon the Btu. The moistened sand is then introduced into a container which is vibrated in order to coat each particle of sand with water, the container is then evacuated to cause the moisture to evaporate with the resultant cooling effect, and subsequently the cooled sand is withdrawn from the container. Two such containers are provided together with automatic controls so that while the pressure in one container is being reduced to cause evaporation, the other container is being supplied with moistened sand. Preferably, only half of the sand in a container is removed after the evaporation process, and the container is then refilled and the vibrating and evacuation step is repeated. Thus, each particle of sand is treated twice in the container, i.e., twice subjected to vacuum and evaporation, with the interval between the first and second cycle serving to insure that heat in the interior of each grain of sand may penetrate to the exterior of the grain and thus assure complete cooling.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an elevational view of the apparatus embodying the invention; and
FIG. 2 is a vertical section along line 2--2 of FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to FIG. 1 of the drawings, the sand cooling apparatus 10 includes a first treatment container 11 and a second treatment container 12. The containers are supported on a base frame 13 by isolation springs 14. Above the containers is a hopper 15 having a flop valve 16 movable by a solenoid 17 from the position shown wherein sand is directed into the container 11 to the opposite position illustrated in dotted lines wherein sand from the hopper will be directed into the container 12. The container 11 is provided with an entry chute 18 opening into the top of the container 11 and a similar chute 19 is provided for the container 12. Each of the chutes 18 and 19 is equipped with a valve such as is shown at 20, with the valves being operated by solenoids 21 and 22 and being effective when actuated to close off the containers 10 and 11 from the atmosphere.
Outlets 23 and 24 are provided at the bottoms of containers 11 and 12 and solenoids 25 and 26 control valves in each of the outlets so as to permit sand to exit from the container onto the upper surface 27 of a belt conveyor. The return flight of the conveyor is indicated at 28.
Associated with the container 11 is a vacuum chamber 29 connected to the container 11 by conduit 30. A vacuum pump 31 is connected by pipe 32 to the vacuum chamber 29 and a solenoid operated valve 33 is arranged to open and close the conduit 30, i.e., to permit or prohibit communication between the vacuum chamber 29 and the container 11.
A second vacuum chamber 34 is connected by means of conduit 35 to the second container 12. Associated with the second vacuum chamber is a vacuum pump 36 connected thereto by pipe 37 and a solenoid operated valve 38 operates in similar fashion to the valve 33.
The vacuum system is arranged to reduce the pressure in the container to cause evaporation of the water coating the grains of sand to effect the cooling. If sand at 150° F. is acceptable, the vacuum system arrangement should release the pressure in the container to about 5 psi absolute or slightly less. If cooler sand is desired, the pressure can be made to go as low as 3 psi absolute or even lower.
Referring now to FIG. 2 of the drawings, there is shown a means for conveying the hot foundry sand to the apparatus previously described. Thus, a belt conveyor 40 is provided with an upper flight 41 on which the hot sand 42 is conveyed toward the hopper 15. The conveyor has a return flight 43. The sand on the upper flight 41 falls into the open top 44 of the hopper 15, and is directed into either the container 11 or 12 by the operation of the flop valve 16.
Closely adjacent the hopper 15 and associated with the belt conveyor 40 is a temperature sensor 45 for sensing the temperature of the sand. A pivoted paddle arrangement 46 is also associated with the container 40 for detecting the depth of the sand on the upper flight 41. The outputs of the temperature sensor 45 and depth sensor 46 are transmitted by leads 47 and 48 respectively to a first control mechanism 49. The control mechanism 49 is arranged to operate a solenoid control valve 50 which controls the rate of flow of water through a pipe 51 into the opening 44 of the hopper 15.
The first control device 49 is arranged to control the flow of water into the hopper 15 at a rate determined by the Btu content of the sand 42. The control device 49 computes the Btu content in response to both the temperature and depth of the sand and regulates the flow of water so as to provide one pound of water for every 1100 Btu's in the sand 42.
Water and sand are introduced into the containers (container 11 shown in FIG. 2) for subsequent treatment. Each of the containers 11 and 12 is equipped with spiral flights 52 running along the interior surface thereof for purposes hereinafter to be described.
Referring again to FIG. 1, means are provided for vibrating each of the containers 11 and 12. As previously pointed out, the containers are supported on isolation springs 14 and thus are mounted for vibratory movement in a general vertical direction. To effect vibration of the container 11 there is mounted thereon a pair of electric motors 53 and 54 on opposite sides of the container with the motors having double-ended shafts, each end carrying eccentrics 55. The axes of the motor shafts are inclined to the vertical as indicated by lines 56 and 57.
Similar motors 58 and 59 are mounted on opposite sides of the container 12 with the motors 58 and 59 carrying double-ended shafts on the ends of which are mounted eccentric weights 60. Like the motors on container 11, the axes of the motor shafts on container 12 are inclined to the vertical as indicated by lines 61 and 62.
Load sensors 63 and 64 are mounted on the interior of two of the isolation springs 14, one load sensor being associated with the container 11 and the second with the container 12, with the load sensors being operable to determine the load of sand and water in each of the containers, again for a purpose to be hereinafter described.
A second control device 65 is connected by the leads shown to the load sensors 63 and 64, the outlet valve solenoids 25 and 26 to the top closing valve solenoids 21 and 22, and to the solenoid valves 33 and 38 effecting communication between the vacuum chambers and the containers.
In carrying out the method of the present invention with the apparatus described, the sand and water mixture is introduced into the top 44 of hopper 15 and directed by the flop valve into the container 11. On start-up, the container is filled with the water/sand mixture and the fact of its being filled will be sensed by the load sensor 63 and the control mechanism 65 so as to move the flop valve to a position directing sand and water into the container 12. The control mechanism 65 will then operate the solenoid 21 and close off the top of the container 11 and subsequently to open the solenoid valve 33 to place the interior of the container 11 into communication with the vacuum chamber 29. With the motors 53 and 54 operating, the container 11 will be vibrated vertically in a generally spiral direction, i.e., not directly up and down but with a slight rotation. The vibrational path followed by the container 11 will closely parallel the inclination of the flights 52 with the net result that the water and sand are thoroughly mixed to insure the coating of each grain of sand with a film of water. Vibration of the container is continuous throughout the process.
After initial start-up, and assuming both containers 11 and 12 to be filled with the sand and water mixture, control device 65 actuates solenoid 25 to open the outlet 23 from the container 11 and at the same time operates solenoid 21 to open the top of that container. Solenoid 17 is also operated to move the flop valve to the position shown to direct the sand/water mix into the container 11. In the preferred arrangement, after about one minute approximately one-half of the sand in the container 11 has exited through the outlet 23 and an equal amount has entered through the chute 18. While this is occurring, container 12 is sealed off from the atmosphere and placed into communication with the vacuum chamber 34 by operation of the solenoid valve 38. Preferably, the rate of discharge from the outlet 23 is slightly greater than the rate at which fresh sand/water mixture is introduced into the container. After one minute, control 65 closes the outlet 23 by actuating the solenoid 25. The sand/water mix will continue to flow into the container until the load sensor 63 senses that the container is filled at which time a signal will be delivered to the control 65 which, through actuation of solenoid 21, will operate the valve closing off the top of the container from communication with the atmosphere and actuate the flop valve so as to deliver sand and water mixture to the container 12. The latter container, shortly before the actuation of the flop valve, has been closed off from the vacuum chamber 34 by actuation of the solenoid valve 38 and the solenoid 26 is actuated to open the outlet and discharge the cooled sand. The solenoid 22 is also actuated to open the top of the container 12 so that the sand/water mix may flow therein. In the meantime, with closing off the container 11 by closing of the outlet and inlet, solenoid valve 33 is actuated to place that container in communication with the vacuum chamber 29.
From the foregoing it can be seen that the cooling process is a continuous one with each grain of sand being subjected twice to vacuum treatment. Cooled sand is exiting from one container while fresh hot sand is being introduced, with the timing cycle being such that about one minute (which is the time I prefer) is required to empty half of the contents of the container and to add an equal amount. While one container is being partially (i.e. one-half) emptied of twice-treated sand and refilled with fresh sand for treatment, the other container is subjected to vacuum to effect the cooling.
Even though the containers are vibrated, there will still exist a division between the half of the sand that remained in the container during the emptying operation, and the newly added sand to refill the container. In other words, the sand at the bottom of the container will be that which was introduced in the preceding cycle, not the current cycle, thus assuring the double treatment of each particle.
Thus it can be seen from the foregoing that there is provided a method and apparatus which cools foundry sand by evaporation. Each grain of sand is thoroughly coated with a film of water and then subjected to two vacuum treatments causing the moisture coating the sand to evaporate with the attendant cooling effect, simultaneously permitting the interior heat of each grain of sand to pass to the exterior surface for dissipation with the evaporation. While one container is being emptied of half its load, the other container is being subjected to vacuum, and thus a continuous supply of sand may be treated by being directed into either one container or the other, with the filling operation in one container being carried on while the vacuum treatment is occurring in the other container. | The invention discloses a method and apparatus for cooling hot foundry sand. The method includes the step of adding water to the hot sand with the quantity of water being related to the Btu content of the sand, vibrating the sand/water mix in a closed container, evacuating the container to evaporate the water and cool the sand, and then removing the cooled sand from the container. Apparatus for carrying out the foregoing steps is also disclosed. | 1 |
BACKGROUND AND SUMMARY OF THE INVENTION
This invention relates to variable capacity roller- and vane-type pumps. The rollers and vanes in such pumps operate as piston elements.
According to this invention there is provided a variable capacity pump incorporating inlet and outlet ports and comprising a rotary carrier having slots at its periphery, piston elements mounted in the slots for radial movement, a cam ring encircling the carrier the radially inner surface of which is engaged by the piston elements to pump working fluid from the inlet port to the outlet port of the pump, a casing within which the cam ring is mounted for guided movement to adjust the position of the cam ring relative to the axis of rotation of the carrier and hence the output of the pump, resilient means urging the cam ring into a position in which the quantity of fluid delivered is a maximum and means defining between the casing and the cam ring a chamber communicating with said outlet port, the fluid pressure in said chamber acting on the cam ring in opposition to the spring, and means whereby a damping force is applied to movement of the cam ring which damping force varies in dependence upon the instantaneous position of the cam ring.
Preferably, the damping force increases with movement of the cam ring to increase the output of the pump.
In one arrangement according to the invention a passage communicating with said outlet port opens to said chamber through a venting port which is obstructed to a variable extent by the cam ring in its guided movement, thereby to provide said means for applying a variable damping force.
In alternative arrangements the means for applying the damping force is independent of the supply of pressure fluid from said outlet port. In one such arrangement said means comprises a tapered recess opening to the chamber and a tapered piston connected to the cam ring and disposed in the recess so that said guided movement of the cam ring causes the radial clearance between the piston and the wall of the recess to vary and impose a variable restriction on the flow of the fluid into and out of the recess.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will now be described in more detail with reference to the accompanying drawings in which:
FIG. 1 illustrates one embodiment of the invention;
FIG. 1A illustrates a modification of the arrangement of FIG. 1;
FIG. 2 is a partial end elevation on the line 2--2 of FIG. 1;
FIG. 3 illustrates a second embodiment of the invention;
FIG. 4 illustrates another aspect of the invention; and
FIG. 5 illustrates a detail of FIG. 4.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIGS. 1 and 2, a pump is shown which operates to maintain a constant-pressure output by control of the position or throw of a cam ring 10 encircling a carrier 11 which is mounted on a shaft 12 rotating about a fixed axis. The carrier has peripheral slots in which rollers 13 are slidably mounted. The rollers 13 are urged outward by centrifugal force into rolling contact with the internal surface of the cam ring and, in the illustrated construction, by pressure fluid derived from the pump output and supplied to the inner ends of the slots from galleries 14 in an end plate 15 of an external casing comprising an annular member 16 flanked by end plates 15, 17. Arcuate inlet and outlet ports 24, 27 are formed in the end plate 15. The cam ring 10 can pivot about a roller 18 which is engaged in part-cylindrical recesses in the casing and in the cam ring. A roller 19 is disposed between a part-cylindrical internal surface 20 on the casing and a part-cylindrical external surface 21 of the cam ring, these surfaces being centred on the axis of the pivot roller 18. A spring 23 seated against a tangentially facing internal surface 22 of the casing acts against a radially-outwardly extending lug 20a on the cam ring and urges the cam ring into a position of maximum throw relative to the carrier.
The pivot roller 18 and roller 19 are identical to the rollers 13 on the carrier and have their axial ends similarly in sealing abutment with the two end plates 15, 17 of the pump casing. Rollers 18 and 19 both also form seals between the cam ring and the casing so as to form therewith two sealed chambers 25, 28. Chamber 28 is permanently vented by being in communication with the inlet duct of the pump. Chamber 25 communicates with the delivery or outlet port 27 of the pump through a port 26. The delivery pressure of the pump thus acts against the force of the spring and tends to reduce the throw of the cam ring and hence the output of the pump. The arrangement thus acts to maintain a constant delivery pressure regardless of the pump speed.
The ends of rollers 18 and 19 may if desired be engaged in recesses in the end plates 15 and 17. Roller 18 may be replaced by a semi-cylindrical projection on the cam ring.
The torque acting on the cam ring 10 due to the fluid pressure in the pumping chambers varies in dependence upon the instantaneous positions of the rollers 13. The variations in the torque tend to cause oscillation of the cam ring which, in the illustrated construction, is damped by limiting the dimensions of the port 26 through which fluid flows into and out of the chamber 25. In order to allow the cam ring to move rapidly when either the speed changes or the output pressure changes, the damping effect should be low. At low pump speeds the throw of the cam ring will generally have a high value but the frequency of the oscillating torque is low and the damping effect is required to be high, so that the effective area of the orifice 26 is required to be low. At high pump speeds, the frequency of the oscillating torque is high and the throw of the cam ring will have a low value and the damping effect is required to be so low so that to obtain the same damping effect the area of the port is increased. In the construction illustrated in FIGS. 1 and 2, the effect is achieved by having the orifice 26 in the form of a slot in the end plate of the pump which slot tapers in width in the radially outward direction. Thus, as the throw of the cam ring increases, the effective area of communication between the outlet port 27 and the chamber 25 decreases as the cam ring blanks off an increasing proportion of the area of the slot, providing the required increasing damping effect and vice versa. The shape of the slot can be designed to produce the required damping characteristic.
The arrangement is equally suitable where vanes are employed in place of rollers 13.
By varying the damping effect in this manner, the maximum response time of the cam movement to counteract variations of external pressure or change in the pump speed can be minimised.
The friction force of the rollers or vanes on the cam ring depends upon the number of rollers or vanes and, therefore, the fewer used, the more efficient the pump. However, the fewer the number of rollers or vanes, the greater the fluctuation in the torque on the cam ring. The variable damping enables fewer rollers or vanes to be used for the same response time of the system.
In a modified arrangement shown in FIG. 1A, a port 26a provides unrestricted communication between chamber 25 and the outlet port 27 of the pump and the variable damping is achieved by employing a restriction 32 in the communication 33 between the inlet port 24 and chamber 28 operating in a similar manner to the port 26 in the arrangement of FIG. 1, the effective area of restriction 32 being determined by the position of the cam ring.
In an alternative arrangement shown in FIG. 3, the port 26 has a constant area, being radially outward of the cam ring, and the variable damping is obtained by forming a frusto-conical recess 30 in the radially outer wall of the chamber and engaging in the recess a frusto-conical piston 31 connected to the cam ring 10. The permitted rate of flow of working fluid past the piston is reduced as the throw increases, so providing an increasing damping effect.
It will be clear that other forms of variable damping device can be employed to act on the movement of the cam ring.
In another aspect of the invention, the rate of spring 23 is matched to the increase in the external pressure in chamber 25 so as effectively to compensate for the spring rate to a substantial extent. The force giving rise to this external torque acts in a direction perpendicular to a straight line joining the circumferential line joining the ends of chamber 25 adjacent the rollers 18 and 19 and acts generally through the centre of the cam surface and very generally parallel to the line of action of spring 23. Thus, the spring rate multiplied by the spring deflection in movement of the cam ring from its minimum to its maximum output position multiplied by the perpendiular distance of the line of action of spring 23 from the axis of roller 18 is equated to the resultant external force on the cam ring due to the required rise in pressure in the chamber 25 in movement of the cam ring from its minimum to its maximum output position multiplied by the perpendicular distance of the line of action of this resultant from the axis of pivot roller 18, divided by the cosine of the angle between the lines of action of the spring force and said resultant. From this equation the required spring stiffness can be obtained.
Referring now to FIG. 4, the forces acting on the cam ring will be considered. The cam ring is shown in its position of zero output, i.e. mid-way between the points X and Y where the cam ring makes contact with the carrier in the two extreme positions of the cam ring. At this position of zero output the centre of the carrier is a distance Ecm. above a line extending through the axis of pivot roller 18 and normal to a line XY.
Suppose that the cam ring rotates through an angle θ to cause the delivery pressure to rise to P Kg/cm 2 at a speed of ω r.p.m.
Then the throw of the cam ring will become E-B sin θ where B is the distance of the centre of the cam ring from its fulcrum 35, i.e. the axis of the pivot roller 18 and the length of the spring 21 will become H-A sin θ where H is the original compressed length of the spring and A is the distance between the axis of pivot roller 18 and the centre-line of the spring.
The following forces are then acting on the cam ring:
1. A force on the outside of the cam ring due to pressure P acting over an effective area of D×W, this force acting at an effective distance D/ 2 from the fulcrum point (where D is the distance from the fulcrum 35 to the sealing point of roller 19 with the cam ring and W is the axial length of the cam). This force gives rise to an anti-clockwise torque on the cam ring of ##EQU1##
2. A force on the inside of the cam ring due to the pressure P acting over an effective area of C×W (where) C is the distance XY and W is the axial length of the cam ring such as to produce an anti-clockwise torque on the cam ring of C×W×P×(E-B sin θ).
3. A force on the inside of the cam ring due to the frictional drag of the rollers pressing against the cam ring. This force is dependent on both the pressure of the system and the centrifugal force of the rollers outward, which varies with speed, and gives rise to a clockwise torque on the cam ring which can be represented as K 1 P+K 2 ω 2
4. A force due to the spring, which will be dependent on the compression of the spring (G-(H-A sin θ)S (where G is the uncompressed length of the spring and S is the spring stiffness in kg/cm). This will give rise to a clockwise torque on the cam ring of [G-(H-A sin θ]S×A.
Under equilibrium conditions the sum of the torques will be zero, i.e. ##EQU2## The effect of the centrifugal force (K 2 ω 2 ) on the rollers is small and can be ignored, i.e.
GAS-HAS-SA.sup.2 Sin θ=1/2PD.sup.2 W+PCWE-PCWB Sin θ-K.sub.1 P
Since GAS, HAS, 1/2D 2 W, CWE and K 1 are constant, then if ##EQU3## the pressure will remain constant for varying values of θ, i.e. if a spring of stiffness ##EQU4## is used in a pump required to operate at a constant pressure P, the spring rate will be compensated for by other variables operating in the pump. | A variable-capacity roller- or vane-type pump has a cam ring which is movable to vary the delivery of the pump and means is provided for applying to the movement of the cam ring a damping force which varies in dependence upon the instantaneous position of the cam ring. | 5 |
Background of the Invention
[0001] There are a number of vascular malformations, defects, or injuries that commonly occur along the lining of the intestine and other parts of the gastrointestinal tract. Some of the more common types include angiodysplasias or telangiectasias (esophageal, gastric, duodenal, jejunal, ileal, colonic, rectal; Helmrich et al., Southern Medical Journal 83:1450-1453 (1990)), watermelon stomach (Gretz and Achem, Am. J Gastroentero. 93:890-895 (1998); Binmoeller and Lieberman, Gastrointest Endosc 37:192-193 1991);, gastric antral vascular ectasias, and radiation injury (radiation proctitis, esophagitis, gastritis, enteritis). A typical characteristic of these types of disorders is undesired bleeding (Lewis, Gastroenterology Clinics of North America 23:67-91; and Jaspersen et al., Gastrointest Endosc 40:40-44 (1994)). Indeed, gastrointestinal bleeding accounts for at least 2% of all hospital admissions each year (Levy, N. Engl. J Med 290:1158 (1974)).
[0002] Conventional treatment of the foregoing disorders includes thermal treatment (Jensen et al. Gastointest Endosc 45:20-25 (1997); Askin and Lewis, Gastrointest Endosc 43:580-583 (1996), Argon Plasma coagulation ( Wahab et al., Endoscopy 29 : 176 - 181 ( 1997 ), and/or laser treatment (Taylor et aL, Gastrointest Endosc 52:353:357 (2000)). However, these conventional methods are not without their drawbacks. The medical equipment is relatively costly and can be cumbersome to use. Furthermore, they present the potential risks of perforation (Pierzchajilo, Colonoscopy, 22:451-470 (1995); Bedford et al., Am J Gastroenterol., 87:244-247 (1987)), or in the case of thermal treatment, heart disrythmias or even colonic explosions (Monahan et al, Gastrointest Endosc 38:40-43 (1992); Vellar et al., Br. J Surg. 73:157-158 (1986); Donato and Memeo, Dis Colon Rectum 36:291-292 (1993); Shinagawa et aL, Br. J Surg. 72:306 (1985)). Argon plasma coagulation has been shown to cause inflammatory polyps (Schmeck-Lindenau and Heine, Endoscopy 30:93-94 (1998).
[0003] U.S. Pat. Nos. 6,187,346 and 6,165,492 to Neuwirth et al. disclose chemical cauterization devices and methods used for treatment of lesions occuring in the uterus. The system taught in these patents involves filling the uterus with a caustic agent, such as silver nitrate, and then neutralizing the cauterizing agent with a sodium chloride solution. However, the methods taught in U.S. Pat. Nos. 6,187,346 and 6,165,492 are not applicable to situations where filling a cavity, such as the uterine cavity, is not possible. Furthermore, these patents do not teach devices that control delivery of a caustic agent as to allow for focal treatment of a confined area of tissue.
[0004] In view of the problems associated with traditional treatments, there is a need in the art for a cautery method that overcomes these problems, and provides an easy to use, inexpensive system for cauterization. While gastroenterologists encounter a number of chronic bleeding disorders, other medical disciplines, such as otorhinolaryngology, pulmonology, gynecology, urology, general surgery, thoracic surgery, and orthopedic surgery, may encounter deformations, defects, and/or injuries that result in undesired bleeding as well. Ideally, the new cautery method would be readily adaptable for use in medical procedures in the GI tract but also other organ systems.
SUMMARY OF THE INVENTION
[0005] The subject invention is directed to a novel cautery system which provides localized cauterization and is easily adaptable for implementation in a number of surgical and non-surgical procedures. Specifically exemplified is a cautery system that delivers a liquid caustic agent to a site of need, wherein the liquid caustic agent is administered through the use of a catheter or other similar device. According to one aspect, the subject invention pertains to a catheter that has a regulating tip at one end, wherein the regulating tip has an impeder, such as, e.g., a sponge, fritted glass or other porous material disposed therein. As the tip contacts, or is placed proximate to, a site of need, a controlled amount of the caustic amount is released. Alternatively, the regulating tip has other configurations to allow for the controlled delivery of the caustic agent, such as the provision of a barrier having one or more small holes. The regulating tip enables controlled, focal delivery of the caustic agent whereby contact with non-target areas is avoided.
[0006] At the other end of the catheter, opposite to the regulating tip, the catheter is connected to a container for storing and supplying the caustic agent. A preferred container is a syringe comprising a plunger, barrel and a connecting end. More preferably, the catheter is equipped with an attachment means such as a female or male luer-lok end, which readily attaches to a syringe comprising the caustic agent.
[0007] According to a further aspect, the subject invention pertains to a method of delivering a caustic agent utilizing the cautery device of the subject invention. The subject method can be used to treat various malformations, defects, and injuries.
[0008] In yet another aspect, the subject invention pertains to a kit comprising a syringe, a catheter and a volume of a caustic agent.
[0009] These and other advantageous aspects of the subject invention will be described in further detail below.
DESCRIPTION OF THE DRAWINGS
[0010] [0010]FIG. 1 shows an embodiment of the subject invention that comprises a catheter connected to a syringe containing a caustic agent.
[0011] [0011]FIG. 2 shows a magnified view of the tip of the catheter shown in FIG. 1.
[0012] [0012]FIG. 3 shows a number of alternate configurations of the regulating tip of the subject invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0013] As discussed above, the subject invention is directed to medical devices useful as a cautery, and specifically for delivering a caustic agent to a site of need. Turning to the drawings, FIG. 1 shows an embodiment of the subject cautery device 100 that comprises a flexible catheter 110 . The catheter 110 has a first end 113 (out of which a caustic agent is delivered), a flexible, elongated portion 115 , and second end 117 that has a female luer-lock 119 connector disposed thereon for attaching to a male luer-lock end 123 of a syringe 121 . During typical use of the cautery device 100 , the syringe 121 is provided with an amount of a caustic agent and attached to the female luer-lock connector 119 . The first end 113 and elongated portion 115 of the catheter 110 are guided through an endoscope and positioned proximate to site of need. By applying pressure to the plunger 125 of the syringe 121 , the caustic agent travels through the catheter 110 and is ejected out at the first end 113 and onto the site of need in a controlled manner.
[0014] Shown in FIG. 2 is close-up depiction of the first end 113 of the catheter 110 up from the break line AA. FIG. 2 illustrates the placement of a permeable material 130 (fritted glass, sponge, etc.) in the first end 113 , which governs the delivery of the caustic agent out of the catheter 110 . The provision of the liquid permeable material 130 prevents uncontrolled spilling and flow of the caustic agent out of the first end 113 , thereby limiting contact of the caustic agent with surrounding tissues. The permeable material 130 is preferably a sponge, fritted glass, or a semi-permeable membrane. Those skilled in the art, in view of the teachings herein, will readily appreciate that various materials can be used to make the permeable material.
[0015] [0015]FIG. 3 shows alternative embodiments of the first end of the catheter which allows for controlled delivery of the caustic agent. FIG. 3A shows an embodiment which comprises a roll-on ball 310 attached to the first end 113 B for applying caustic agent to the site of need. FIG. 3B shows an embodiment which comprises a closed first end 113 C with a plurality of perforations 315 out of which caustic agent is ejected. FIG. 3 C shows an embodiment which has a permeable membrane 320 rigidly attached to the first end 113 D.
[0016] A number of conventional materials commonly used in the medical industry can be used to make the catheter 110 . Examples of such materials include, but are not limited to, polyvinyl chloride, polyethylene, polypropylene, polyethylene terephthalate, polyurethane, polytetrafluoroethylene, fluoroethylenepropylene, or nylon, or combinations thereof. Examples of suitable materials are disclosed, e.g., in U.S. Pat. Nos. 6,165,166; 4,707,389, 3,561,493. The structural properties of the subject cautery device and catheter will be dictated by the intended use. For example, use of the subject cautery device with a flexible endoscope will require that the catheter is also flexible. Those skilled in the art will readily recognize appropriate materials for making such catheters to meet this requirement, as well as in the case where there is a need for a more rigid catheter.
[0017] The subject cautery device has a number of applications, in a number of different medical disciplines. With respect to gastroenterology, the subject invention may be useful to treat, for example, vascular malformations, watermelon stomach, gastric antral vascular ectasias, radiation injury, benign neoplasms, post-polypectomy bleeding, post-endoscopic ampullary sphincterotomy bleeding, ulcers, Dieulafoy's lesions, malignant neoplasms, Barrett's esophagus with or without dysplasia, varices, bleeding Mallory-Weiss tears, bleeding from portal hypertensive gastropathy, fistulae, or bleeding from colitis.
[0018] Examples of caustic agents appropriate for use with the teachings herein include, but are not limited to, silver nitrate, zinc chloride, copper sulfate, phenol, acids, alkali, iodine, potassium permanganate, or combinations thereof. Furthermore, depending on the intended use, the viscosity and strength or concentration of the selected caustic agent is routinely adjusted. Where deeper penetration of the caustic agent is preferred, a more concentrated solution of the caustic agent should be used. Other characteristics such as speed and severity of cautery are adjusted as well, depending on the desired use and may be achieved by altering viscosity.
[0019] The activity of the caustic agent is readily controlled by using silver compounds such as silver nitrate and silver thiocyanate or other compounds which can release silver ions. The silver ions react with the sulfides, proteins, and chlorides in cells. Since the sulfides and chlorides are vital to cell metabolism, the reaction results in necrosis of the cells. Another potentially useful agent is iodine which is radiopaque like silver. Compositions containing iodine react with the target tissue as the result of the release of elemental free Iodine and the reaction can be stopped by forming a stable compound, for example, sodium iodide. In an especially preferred embodiment, silver nitrate and DEXTRAN 70® are utilized together because they are easy to work with, are controllable, and are recognized by the medical profession and government regulatory agencies as acceptable agents for human use. DEXTRAN 40®. and 70® can be used intravenously and intramuscularly and in several organ systems such as the genital tract. Silver Nitrate is used on the skin, upper respiratory tract, lower genital tract, and other locations. The silver ion has a loose but stable binding with the dextran carrier but is pulled off by the consumption of the ion at the tissue sites by binding to anions and protein. The carrier may be made of dextrans or glucose or other sugars used in intravenous solutions but preferably in concentrations sufficient to form gels or pastes. The compositions prepared in accordance with this invention have a viscosity that is suitable for their intended purpose at temperatures between about 20° C. and about 37° C., however, the viscosity may be adjusted as specific applications dictate. Alginates, aloe, carboxymethylcellulose, silicones and oxidized cellulose may also be used to form pastes and gels but the dextrans and sugars are the preferred choices because of their acceptance by the medical profession and regulatory agencies.
[0020] The speed and severity of the chemical necrosis may be regulated by the percentage of the silver nitrate in the paste. By increasing the percentage of the silver nitrate in the paste the possibility for a deeper burn is increased. It is possible, by procedures well known to those skilled in the art, to determine the appropriate concentration of silver nitrate to achieve the desired depth of cauterization for specific applications. The practitioner may readily formulate a paste that is essentially self regulating. For example, a weak silver nitrate paste may be formulated that will expend itself after necrosing to a depth of only half the maximum safely allowable depth, thereby reducing the danger of necrosing too deeply. Preferably, the composition comprises 1-50%, by weight, of caustic agent. More preferred, the caustic agent comprises 10-40%, by weight of the composition. Alternatively, the practitioner may easily terminate the treatment by introducing a normal saline solution, e.g., NaCl, which will deactivate the silver nitrate by forming silver chloride. An advantage of the silver nitrate is that the deactivating agent for the silver ion is the chloride ion found in several solutions used regularly in medicine, e.g., intravenously and intramuscularly, such as normal saline or Ringer's solution. The silver nitrate deactivation is the essentially stoichiometric formation of an insoluble non-caustic precipitate.
[0021] The viscosity of the caustic composition may be adjusted so that it does not flow uncontrollably from the site of need. The caustic composition should flow easily, i.e, without excessive pressure, through a catheter having an inside diameter of about 2 mm. Preferably, the caustic composition should be thick enough that it does not run, i.e, it stays in the vicinity of the point of application. In a preferred embodiment, a caustic composition having a consistency ranging from toothpaste to pancake syrup is utilized as specific applications dictate. Thixotropic caustic compositions utilizing, e.g., mineral clays or the like, may be especially useful in some applications. While modifying the viscosity of the cauterizing compound can alter the flow properties and therefore aid in the control of delivery, the subject cautery device allows for controlled delivery of a cauterizing agent having a broad range of viscosities as result of its regulating tip.
[0022] Preferably, about 10 gms of DEXTRAN 70® is mixed with about 10 ml of water containing varying concentrations of silver nitrate, which flows slowly and smoothly under pressure through a 2 mm catheter 30 cm to 260 cm long attached to a 10 ml syringe. However, the concentrations may be varied as specific applications dictate to meet the conditions of delivery and the organ or structure to be treated. The low viscosity or “watery” compositions comprise about 5 gms of DEXTRAN 70® and about 10 ml water and the high viscosity or “thick paste” compositions are comprised of about 10 gms to about 15 gms or higher of DEXTRAN 70® and about 10 ml water.
[0023] The teachings of all patents and publications cited throughout this specification are incorporated by reference in their entirety to the extent not inconsistent with the teachings herein.
[0024] It should be understood that the examples and embodiments described herein are for illustrative purposes only and that various modifications or changes in light thereof will be suggested to persons skilled in the art and are to be included within the spirit and purview of this application and the scope of the appended claims. | Disclosed herein are novel cautery devices, and methods and kits implementing the same. The disclosed devices are especially useful for localized delivery of a liquid caustic agent to treat various defects, malformations and injuries resulting in bleeding. The disclosed devices have uses in a number of medical disciplines, and specific examples are provided pertaining to treatment of defects, malformations, and injuries, or bleeding due to medical procedures, in and along the gastrointestinal tract. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of U.S. patent application Ser. No. 09/333,814, filed Jun. 15, 1999 now U.S. Pat. No. 6,115,314 which is a divisional of U.S. application Ser. No. 08/997,498 filed Dec. 23, 1997, and issued as U.S. Pat. No. 5,923,604.
TECHNICAL FIELD
This invention relates to synchronous memory devices, and more particularly, to a method and apparatus for more quickly processing addresses applied to synchronous memory devices.
BACKGROUND OF THE INVENTION
Memory devices are in widespread use in computers, particularly personal computers. The system memory of such computers is generally provided by dynamic random access memories (“DRAMs”). DRAMs were initially asynchronous in which commands and addresses were received and processed by DRAMs at a rate that was not determined by a periodic signal. However, in an attempt to reduce memory access times and facilitate pipelining of memory accesses. synchronous DRAMs (“SDRAMs”) were developed.
In a SDRAM, memory accesses are synchronized to an external clock that is applied to the DRAM so that one memory access, i.e., a read or write, occurs each period of the clock. An example of a conventional SDRAM 40 is shown in FIG. 1 . The SDRAM 40 has as its central memory element a memory array 42 that is segmented into two banks 44 , 46 . The SDRAM 40 operates under control of a control logic 48 that receives a system clock signal CLK, a clock-enable signal CKE, and several command signals that control reading from and writing to the SDRAM 40 . Among the command signals are a chip-select signal CS*, a write-enable signal WE*, a column address strobe signal CAS*, and a row address strobe signal RAS*. (The asterisk next to the command signals CS, WE, CAS, and RAS indicate that these signals are active low signals, i.e., the command signals CS*, WE*, CAS*, and RAS* go to a low logic level when active).
In addition to the command signals, the SDRAM 40 also receives addresses from an address bus 52 , and receives or outputs data on a data bus 60 . The received addresses are either bank/row addresses or column addresses. An address on the address bus 52 is designated as a row addresses by a row address strobe RAS* signal transitioning active low when the address is present on the address bus. An address on the address bus 52 is designated as a column addresses by a column address strobe CAS* signal transitioning active low when the address is present on the address bus. As explained below, column addresses can also be generated internally. In any case, addresses from the address bus 52 are clocked into the SDRAM 40 through an address register or address latch 62 . If an address is a row address, the address is coupled to the array 42 through a row address path 64 . The row address path 64 includes a row address multiplexer 66 that receives the external row address from the address latch 62 and receives an internal row address from a refresh circuit 67 . The row address multiplexer 66 provides the row addresses to either of two row address latches 70 depending upon the logic state of the bank address BA. The row address latches 70 latch the row addresses and provide the row addresses to respective row decoders 72 . The row decoders 72 take the 11-bit address from the row address latch 70 and activate a selected one of 2,048 row address lines 73 . The row address lines 73 are conventional lines for selecting row addresses of locations in the memory array 42 . As noted above, the following discussion assumes that the row address has been selected and that the selected row is activated.
After a row address has been received and latched by RAS* going low, a column address may be latched responsive to a column address strobe signal CAS* going active low. If the address received at the address latch 62 is a column address, it is transmitted to the I/O interface 54 and the memory array 42 through a column address path 76 . The column address path includes a column address counter/latch 78 that receives an initial column address from the address latch or buffer 62 and thereafter increments the address once each cycle of the CLK signal. The column address from the column address counter/latch 78 is thus an internally generated column address, as mentioned above.
The internal column address from the column address counter/latch 78 and an external column address from the address latch or buffer 62 are each applied to a multiplexer 79 . The multiplexer 79 selects one of these column addresses based on the nature of the current memory access. If the current memory access is one of several identical memory accesses (i.e., a READ or a WRITE) to successive columns of a row, known as a “burst” memory access, the multiplexer 79 selects the internal address from the column address counter/latch 78 unless a new command is received. If, during a burst memory access, e.g., a burst READ, a new command, e.g., a burst WRITE, is received, the multiplexer 79 selects an external column address from the address latch or buffer 62 .
In operation, the SDRAM 40 assumes a number of states before and during a memory transfer. Initially, the SDRAM 40 is in an idle state prior to the start of a memory transfer. When data are to be read from or written to the memory device, a row address is applied to the address bus 52 and an active low RAS* signal is applied to the command decoder in the control logic 48 . Thus, in the idle state, the only address used by the SDRAM 40 is an external row address. There is therefore never any need to use an internal address in the idle state. The transition of the RAS* signal to an active low state transitions the SDRAM 40 from the idle state to the row active state.
During the row active state, the memory cells in a selected row of the array 42 that corresponds to the row address are coupled to respective digit lines. As is well understood in the art, there are a set of complementary digit lines for each column of the memory arrays 42 . Once the SDRAM 40 has transitioned to the row active state, the SDRAM 40 can transition to the column command state responsive to the RAS* signal transitioning high and the CAS* signal transitioning active low. In the column command state, the SDRAM 40 can receive and process a column address and a column command, such as a READ or a WRITE command. Thus, once the SDRAM 40 transitions from the row active state to the column command state, the SDRAM 40 can process a column address that, as explained above, can be either an external column address applied to the address bus 52 or an internal column address generated by the column address counter latch. When a memory command is received that is not for a burst memory access, the multiplexer 79 selects an external column address from the address latch or buffer 62 . In a burst memory transfer, the column address counter/latch 78 increments the initial column address once each cycle of the CLK signal to generate a number of sequential column addresses corresponding to the length of the burst.
After data are read from or written to the SDRAM 40 , the RAS* signal transitions inactive high to transition the SDRAM 40 back to the idle state during which precharging of the array 42 occurs before the start of another memory access.
As explained further below, the time required to determine whether an internal column address or an external column address should be selected by the multiplexer 79 can significantly slow the rate at which memory accesses can occur. The inventive method and apparatus is adapted to allow this determination to be made at an earlier time so that memory accesses can occur at a faster rate.
After the multiplexer has selected either an internal address or an external address, the multiplexer 79 couples the selected column address to a pre-decoder 102 and a latch 82 . The pre-decoder 102 partially decodes the column address and passes it to a column decoder 84 to complete the decoding. The decoder 84 then selects the column to which data are to be read from or written to.
The input data path 56 transmits data from the data bus 60 to the I/O interface 54 . The output data path 58 transmits data from the I/O interface 54 to the data bus 60 .
During a memory access, the control logic 48 decodes the command signals according to a predetermined protocol to identify the row active state and the column command state for execution by the SDRAM 40 . The row active command then transitions the SDRAM 40 to the row active state as shown in FIG. 2 . Note that the RAS* signal is active low and the CAS* signal is inactive high in the row active state. As mentioned above, in the row active state, the only address that can be processed by the SDRAM 40 is a row address received on the address bus 52 . Thus, in the row active state, there is never a need to process an external column address.
FIGS. 3 and 4 show clock and command signals and their states for write commands and read commands, respectively. Note that, in these commands, the RAS* signal is inactive high and the CAS* signal is active low. The read and write commands differ only in the state of the write-enable signal WE*. The write-enable signal WE* is an active low signal such that, if the write-enable signal WE* is low, the data transfer operation will be a write, as shown in FIG. 3 . If the write-enable signal WE* is high, the data transfer operation will be a read, as shown in FIG. 4 . In the remaining figures, these combination of command signals corresponding to the read and write commands will be shown as simply a “read” command or a “write” command in the interests of brevity and clarity.
With reference to FIG. 5, a no operation (“NOP”) command is the same as the read command shown in FIG. 4 except that CAS* is inactive high rather than active low. The NOP command is used during a burst memory transfer, as explained below. As also mentioned above, an internal address is used for a burst memory transfer while an external column address is used in other memory transfers.
As is conventional to SDRAM operation, the row address is received and stored, and the selected row is activated prior, prior to either a column command or the column address being applied to the address bus 52 (FIG. 1) and the column address strobe signal CAS* going low.
As indicated by the arrow 50 in FIGS. 2-5, the leading edge of each pulse of the clock signal CLK establishes the time at which the states of the signals are determined. The clocking of the control logic 48 by the clock signal CLK is enabled by the clock-enable signal CKE, which is high for reading and writing. Also, reading and writing from the SDRAM 40 is enabled only when the SDRAM 40 is selected, as indicated by the chip-select signal CS*.
The control logic 48 decodes the above-described command signals CKE, CLK, CS*, WE*, CAS*, and RAS* to determine whether the SDRAM 40 is to be placed in either the idle, row active, or column command states. The control logic 48 then controls reading from or writing to the memory array 42 by controlling an I/O interface 54 and input and output data paths 56 , 58 . The I/O interface 54 is any conventional I/O interface known in the art, and includes typical I/O interface elements, such as sense amplifiers, mask logic, precharge and equilibration circuitry, and input and output gating.
The control logic 48 causes the multiplexer 79 (FIG. 1) to couple either an external column address from the address latch or buffer 62 or an internal column address from the column address counter/latch 78 based on the nature of the command signals applied to the control logic 48 . As explained above, if the row address strobe signal RAS* is inactive high, the SDRAM 40 is in the idle state in which none of the rows of the memory array 40 is yet active. Under these circumstances, the SDRAM 40 cannot be in a burst transfer mode in which the column address counter/latch 78 generates an internal counter address. Thus, the control logic 48 prevents the multiplexer 79 from coupling an internal column address from the column address counter/latch 78 to the pre-decoder 102 before a row has been activated, and the row address strobe signal RAS* transitions low. However, when the row address strobe signal RAS* has transitioned active low and a row has been activated, then a memory access can either be an access to a column corresponding to a column address or a burst memory access. In the case of a memory access to a column corresponding to a column address, the multiplexer 79 must couple the external address from the address latch or bar for 62 to the pre-decoder 102 . In the case of a burst memory access, the multiplexer 79 must couple an internal column address from the column address counter/latch 78 to the pre-decoder 102 . In the event the row address strobe signal RAS* is high, the control logic 48 generates an appropriate signal for controlling the multiplexer 79 based on the nature of some of the remaining commands that are applied to the control logic 48 , as explained below.
The operation of the SDRAM 40 for a burst of four read starting at a first column address followed by a burst of four read starting at a second column address is illustrated FIG. 6 . At time to the CLK signal goes high to clock a READ command into the control logic 48 . At the same time, a column address is applied to the address bus 52 of the SDRAM 40 . Although not shown in FIG. 6, the column address strobe signal CAS* goes low at to to clock the column address into the column address counter/latch 78 (FIG. 1 ). The control logic then decodes the READ command to determine that the multiplexer 79 should couple the external address from the address latch or buffer 62 to the pre decoder 102 . The column decoder 84 then causes data to be read from the memory cell in the column corresponding to the column address that intersects the active row corresponding to the last row address.
On the leading-edge of the next clock cycle at t 1 , a NOP command is clocked into to the SDRAM 40 . The column address counter/latch 78 responds to the CLK signal by incrementing, thereby applying a column address to the multiplexer 79 that is one column greater than the previous column address. However, the control logic 48 has not yet determined whether the multiplexer 79 should respond to the internal column address from the column address counter/latch 78 or the external address from the address latch or buffer 62 . Therefore, subsequent to t 1 , the control logic 48 decodes the NOP command and, on that basis, determines that a burst memory access is in process and that the internal column address should be used. The multiplexer 79 then couples the internal column address to the pre-decoder 102 .
In the same manner as described above, the column address counter/latch 78 generates incrementally increasing internal addresses at t 2 and t 3 . In each case, the control logic 48 decodes the NOP command and causes the multiplexer 79 to couple the internal column address from the column address counter/latch 78 to the pre-decoder 102 .
At the leading-edge of the CLK signal at t 4 , a new column command, i.e., a READ from a memory cell at a different column address, is applied to the control logic 48 . Shortly after t 4 , the control logic 48 has decoded the READ command to determine that the multiplexer 79 should couple the external column address from the address latch or buffer 62 to the pre-decoder 102 . Thereafter, the SDRAM 40 responds to the next three NOP commands as a burst of four READ command, as described above.
One problem with the operation of the SDRAM 40 illustrated in FIG. 6 is the time delay needed to determine whether the multiplexer 79 should couple an external column address from the address latch or buffer 62 to the pre-decoder 102 or an internal column address from the column address counter/latch 78 to the pre-decoder 102 . As explained above, the control logic 48 does not begin to make this determination until the column command, i.e., a READ, WRITE, or a NOP command is clocked into the control logic 48 at the leading edge of the CLK signal. After the command has been decoded, the control logic 48 must apply a corresponding signal to the multiplexer 79 , and the multiplexer 79 must then couple either the internal column address or the external column address to the pre-decoder 102 . The amount time required to perform these functions can be considerable. If these functions are not performed quickly enough, the control logic 48 may not control the multiplexer 79 until after the falling edge of the CLK signal when an invalid column address may be present at the address bus 52 or invalid data may be present at the data bus 60 , in the case of a write operation. In fact, the primary technique for preventing this problem from occurring is to limit the frequency of the CLK signal so that the multiplexer 79 can couple either the internal column address or the extra column address to the pre-decoder 102 prior to the trailing edge of the CLK signal. However, limiting the frequency of the CLK signal limits the speed at which data can be read from or written to the SDRAM 40 .
One reason why conventional SDRAMs 40 cannot operate at optimum speed is the relatively long time required to decode the commands. As shown in FIGS. 2-5, the control logic 48 must decode four command signals (i.e., CS*, RAS*, CAS*, and WE*) to determine the state of the SDRAM 40 and the nature of any column command (i.e., a READ or a WRITE command). The time required for conventional decoder circuits to decode command signals increases markedly with the number of signals that must be decoded. Since the control logic 48 must decode four command signals to determine whether an internal column address or an external column address should be used, decoding the command signals limits the operating speed of conventional SDRAMs. There is therefore a need to be able to increase the rate at which command signals can be decoded to select either an internal or external column address.
SUMMARY OF THE INVENTION
A method and apparatus for coupling either an external address terminal or an internal address terminal to a column address decoder in a synchronous memory device. The decoder decodes, only column command signals to determine whether the command signals corresponds to a column command or a bust command. If the column command signals correspond to a column command, the external address terminal is coupled to the address decoder. If the column command signals do not correspond to a column command, the internal address terminal is coupled to the address decoder. The column command signals are preferably decoded prior to a transition of a clock signal that initiates a memory access. Decoding the column command signals is preferably enabled only if the memory device is in a column command state after a row of the memory device has been activated. If a row has not been activated, the external address terminal is coupled to the row address decoder without the need to check other command signals. The column address decoder is coupled to either the external address terminal or the internal address terminal by a multiplexer responsive to a multiplexer control signal. The multiplexer control signal is generated by a column command signal decoder that decodes only the column command signals, preferably prior to the transition of the clock signal that initiates a memory access.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram of a prior art synchronous dynamic random access memory (“SDRAM”) that can advantageously use one embodiment of an address selection circuit in accordance with the invention.
FIG. 2 is a timing diagram showing the combination of command signals that correspond to a ROW ACTIVATE command in the SDRAM of FIG. 1 .
FIG. 3 is a timing diagram showing the combination of command signals that correspond to a WRITE command in the SDRAM of FIG. 1 .
FIG. 4 is a timing diagram showing the combination of command signals that correspond to a READ command in the SDRAM of FIG. 1 .
FIG. 5 is a timing diagram showing the combination of command signals that correspond to a no operation (“NOP”) command in the SDRAM of FIG. 1 .
FIG. 6 is a timing diagram showing the combination of command signals that correspond to a pair of burst READ memory accesses in the SDRAM of FIG. 1 .
FIG. 7 is a logic diagram of one embodiment of a column address selection circuit in accordance with the present invention.
FIG. 8 is a timing diagram showing various signals present in the column address selection circuit of FIG. 7 .
FIG. 9 is a block diagram of a computer system using the SDRAM of FIG. 1 containing the column address selection circuit of FIG. 7 .
DETAILED DESCRIPTION OF THE INVENTION
An address selection circuit 200 in accordance with one embodiment of the invention is illustrated in FIG. 7 . The operation of the address selection circuit 200 will be explained with reference to the timing diagram of FIG. 8 .
The address selection circuit 200 may be part of the control logic 48 (FIG. 1 ), and it generates an address selection signal IB_BO and its complement IB_BO* to control the coupling of an internal column address or an external column address to the I/O interface 54 for Bank 0 . (In the SDRAM of FIG. 1, the column decoder 512 includes multiplexers that couple the output of the column decoder 84 to either the I/O interface 54 for Bank 0 or the I/O interface 54 for Bank 1 ). Similarly, the address selection circuit 200 generates an address selection signal IB_B 1 and its complement IB_B 1 * to control the coupling of an internal column address or an external column address to the I/O interface 54 for Bank 1 . When the IB_B 0 signal is high (and its complement IB_BO* is, of course, low), an external column address from the address latch or buffer 62 is coupled from the column decoder 84 to the I/O interface 54 for Bank 0 . When the IB_B 0 signal is low, an internal column address from the column address counter/latch 78 is coupled from the column decoder 84 to the I/O interface 54 for Bank 0 . Similarly, when the IB_B 1 signal is high, an external column address from the address latch or buffer 62 is coupled to the I/O interface 54 for Bank 1 , and when the IB_B 1 signal is low, an internal column address from the column address counter/latch 78 is coupled to the I/O interface 54 for Bank 1 . Thus, a high IB signal selects an external column address and a low IB signal selects and internal column address.
The address selection circuit 200 receives a latched row address strobe signal RAS 0 *, RAS 1 * for each memory bank 42 as well as a chip select signal CS*, and a column address strobe signal CAS*. As is a well known in the art, other circuitry in the control logic 48 generates the latched RASO* and RAS 1 * signals as well as a latched column address strobe signal CASL*. The RAS 0 * and RAS 1 * signals are generated by conventional circuitry (not shown) that latches the RAS* signal applied to the SDRAM 40 on the rising edge of the CLK signal. The output of the latch then sets an S-R flip-flop that then outputs active low RAS 0 * and RAS 1 * signals, depending on the bank selected by the bank address. The S-R flip-flop is reset at the start of the row active state by conventional means. Thus, once RAS 0 * and RAS 1 * transition low, they remain low for the entire period of the column command state. The latched column address strobe signal CASL* is also generated by conventional circuitry (not shown) elsewhere in the SDRAM 40 . Basically, CASL* is generated by setting a latch when CAS* and CS* are both active low. The clock signal CLK, chip select signal CS*, column address strobe signal CAS*, and latched column address strobe signal CASL* are shown in FIG. 8 .
The address selection circuit 200 contains basically three sections. A first section 202 controls the address selection signals IB_B 0 and IB_B 0 * for the first memory bank based on the state of the first row address strobe signal RAS 0 *, a third section 204 similarly controls the address selection signals IB_B 1 and IB_B 1 * for the second memory bank based on the state of the second row address strobe signal RAS 1 *. A second section 206 controls the address selection signals for both memory banks 42 based on the state of the column commands, i.e. the chip select signal CS* and the column address strobe-signal CAS*.
The first section 202 includes a NOR gate 210 that receives the CLK signal and the first row address strobe signal RAS 0 * through an inverter 214 . The output of the NOR gate 210 is applied to a flip-flop 215 formed by a pair of NOR gates 216 , 218 . The NOR gate 218 also receives the complement of RAS 0 * from the output of the inverter 214 . As mentioned above, if RAS 0 * is low, the SDRAM 40 is in the row activate state in which the multiplexer 79 will never use and internal address. Therefore, when RAS 0 * is a low, the high at the output of the inverter 214 sets the flip-flop 215 , thereby causing the NOR gate 218 to output a low. The low at the output of the NOR gate 218 is applied to a NAND gate 230 which then outputs a high. The high at the output of the NAND gate 230 is coupled through a pair of inverters 232 , 234 to generate a high IB_B 0 signal and a low IB_B 0 * signal that, as explained above, selects an external address.
If the row address strobe signal RAS 0 * is inactive high, the SDRAM 40 may respond to a column address, which may be either an internal column address or an external column address. If RAS 0 * is high, the inverter 214 outputs a low that causes the NOR gate 210 to output a high on the subsequent leading edge of the CLK signal. The NOR gate 210 then reset the flip-flop 215 to cause the NOR gate 218 to output a high that enables the NAND gate 230 . The output of the NAND gate 230 is then controlled according to the nature of the column command signals to select either an internal column address or an external column address.
The third section 204 operates in the same manner as the first section 202 to provide address selection signals IB_B 1 and IB_B 1 * for the Bank 1 42 of the SDRAM 40 based on the state of the second row address strobe signal RAS 1 *. An explanation of the structure and operation of the third section 204 will thus be omitted in the interest of brevity.
With further reference to FIG. 7, the active low chip select signal CS* and the active low column address strobe signal CAS*, and the clock signal CLK are applied through respective inverters 240 , 242 , 244 to a NAND gate 246 . Referring to FIG. 8, when the SDRAM 40 is being accessed, the chip select signal CS* will be active low. Thus, when the column address strobe signal CAS* goes low at t 0 , the output of the NAND gate 246 will go low since the clock signal CLK is low at time t 0 . As explained above, a low column address strobe signal CAS* is indicative of a column command such, as a READ command or a WRITE command. As further explained above, the multiplexer must couple an external address to the pre-decoder 102 in the event of a column command. Thus, when a column command is decoded by the NAND gate 246 , the output of the NAND gate 246 will go low. The low at the output of the NAND gate 246 forces the output of the NAND gate 230 high, thereby making the address selection signals IB_B 0 high and IB_B 0 * low to couple an external address to the pre-decoder 102 . Thus, as shown in FIG. 8, the address selection signal IB_B 0 , 1 goes high at t 0 .
The output of the NAND gate 246 is also applied to a NAND gate 250 . The output of the NAND gate 250 is coupled through a pair of inverters 252 , 254 to generate address selection signals IB_B 1 and IB_B 1 * for the memory Bank 1 . The signals are generated in the same manner as the address selection signals for Bank 0 , as explained above.
When the clock signal CLK goes high at t 1 , the low at the output of the inverter 2244 causes the output of the NAND gate 246 to go high. As a result, the address selection signals IB_B 0 , 1 would go low if it were controlled entirely by the output of the NAND gate 246 . However, the address selection signals IB_B 0 , 1 are also controlled by the output of a NAND gate 260 . The NAND gate 260 receives the CLK signal as well as the complement of the active low latched column address strobe signal CASL* through an inverter 264 . As shown in FIG. 8, CASL* goes low and CLK goes high at time t 1 . As a result, the output of the NAND gate 260 goes low at time t 1 . The low at the output of the NAND gate 260 maintains the respective outputs of the NAND gates 230 , 250 high, thus maintaining the address selection signals IB_B 0 , 1 high.
When the CLK signal goes low at time t 2 , the output of the NAND gate 260 goes high, but the output of the NAND gate 246 goes low to maintain the address selection signals IB_B 0 , 1 high. Thus, the multiplexer continues to select an external column address. However, a conventional SDRAM like the SDRAM 40 shown in FIG. 1 only responds to column commands when CLK is high. Therefore, the state of IB_B 0 , 1 when CLK is low is not significant since the column address is not used at that time.
With further reference to FIG. 8, at time t 3 , CAS* goes high to change the column command from a READ command to a NOP command. As explained above with reference to FIG. 6, a NOP command causes a burst memory access to occur on each rising edge of the CLK signal. During a burst memory access, the multiplexer must select an internal column address generated by the column address counter/latch 78 (FIG. 1 ). When CAS* goes high at t 3 , the output of the NAND gate 246 goes high since CLK is low at time t 3 . Since the output of the NAND gate 260 is also high at that time because the CLK signal is low, the respective outputs of the NAND gates 230 , 250 go low, thereby making the address selection signals IB_B 0 , 1 low. As a result, the internal column address from the column address counter/latch 78 is selected. At time t 4 , the high CAS* signal is latched on the leading edge of the CLK signal to transition CASL* high. The high CASL* signal maintains the output of the NAND gate 260 high after t 4 when the CLK signal goes high. As a result, the internal column address continues to be selected by the multiplexer as a burst READ occurs on each leading edge of the CLK signal.
The primary advantage of the preferred embodiment of the address selection circuit shown in FIG. 7 is the earlier time at which the address selection signals IB_B 0 , 1 are generated as compared to prior art techniques. As explained above, using prior art circuitry, the address selection signals are not generated until command signals are latched into the control logic 48 on each rising edge of the CLK signal. Thus, using the prior art approach, the low CAS* signal after time to would not be latched into the control logic 48 until time t 1 . Decoding of the command signals would thereafter occur and the address selection signals IB_B 0 , 1 would therefore not be generated until sometime after time t 1 . In contrast, the address selection circuit 200 illustrated FIG. 7 is able to generate the address selection signals IB_B 0 , 1 at a somewhat earlier time at t 0 because it decodes the command signals CS* and CAS* prior to the rising age of the CLK signal. The output of the NAND gate 246 thus sets up the address selection signals IB_B 0 , 1 , and the NAND gate 260 thereafter maintains the address selection signals in that condition.
In a similar manner, prior art circuitry would not decode the NOP command generated at time t 3 until the subsequent rising edge of the CLK signal at time t 4 . As a result, the prior art circuitry could not generate address selection signals IB_B 0 , 1 to select an internal column address until sometime after time t 4 . However, by decoding the NOP command starting at time t 3 , the address selection circuit 200 is able to generate the address selection signals IB_B 0 , 1 at a somewhat earlier time. Consequently, when a memory access is initiated on the rising edge of the CLK signal, the pre-decoder 102 (FIG. 1) is already connected to the proper source of the column address. The SDRAM 40 using the address selection circuit 200 may thus be able to operate at a higher clock frequency, thus allowing the SDRAM 40 to read and write data at a faster rate.
The address selection circuit shown in FIG. 7 also has the advantage of being able to generate the address selection signals IB_B 0 , 1 at an earlier time because it requires that only two command signals be decoded. More specifically, the address selection signals IB_B 0 , 1 are generated responsive to decoding only CAS* and CS*. As explained above, the conventional approach to generating the address selection signals IB_B 0 , 1 requires that four command signals be decoded. As further explained above, decoding four command signals requires significantly more time than is required to decode only two command signals. Thus, the address selection circuit of FIG. 7 is able to provide the address selection signals IB_B 0 , 1 at an earlier time than is possible with the conventional approach for two reasons. First, by decoding command signals prior to the rising edge of the clock signal CLK that is used to initiate a memory access. Second, by decoding only two command signals to generate the address selection signals IB_B 0 , 1 .
The SDRAM 40 can be used in a computer system, as shown in FIG. 9 . With reference to FIG. 9, the computer system 300 includes a processor 302 having a processor bus 304 coupled through a memory controller 305 to the SDRAM 40 . The computer system 300 also includes one or more input devices 310 , such as a keypad or a mouse, coupled to the processor 302 through a bus bridge 312 and an expansion bus 314 , such as an Industry Standard Architecture (“ISA”) bus or a Peripheral Component Interconnect (“PCI”) bus. The input devices 310 allow an operator or an electronic device to input data to the computer system 300 . One or more output devices 320 are coupled to the processor 302 to display or otherwise output data generated by the processor 302 . The output devices 320 are coupled to the processor 302 through the expansion bus 314 , bus bridge 312 and processor bus 304 . Examples of output devices 320 include printers and video display units. One or more data storage devices 322 are coupled to the processor 302 through the processor bus 304 , bus bridge 312 , and expansion bus 314 to store data in or retrieve data from storage media (not shown). Examples of storage devices 322 and storage media include fixed disk drives floppy disk drives, tape cassettes and compact-disk read-only memory drives. The computer system 300 also includes a number of other components and signal lines that have been omitted from FIG. 9 in the interests of brevity.
In operation, the processor 302 communicates with the SDRAM 40 via the memory controller 305 . The memory controller 305 sends the SDRAM 40 control and address signals. Data is coupled between the processor 302 and the SDRAM 40 through the memory controller 305 , although the data may be coupled directly to the data bus portion of the processor bus 304 . The memory controller 305 applies write data from the processor 302 to the SDRAM 40 , and it applies read data from the SDRAM 40 to the processor 302 .
From the foregoing it will be appreciated that, although specific embodiments of the invention have been described herein for purposes of illustration, various modifications may be made without deviating from the spirit and scope of the invention. Accordingly, the invention is not limited except as by the appended claims. | A method and apparatus are disclosed for selecting either an external column address or an internal column address in a synchronous memory device. The external or internal address is selected by decoding command signals applied to the memory device. If the command signals correspond to a read or a write memory access, an external column address is selected. If the command signals correspond to a burst read or write memory access, an internal column address is selected. Significantly, the command signals are decoded prior to the transition of a clock signal that initiates a memory access so that a column address decoder is already connected to the proper column address source prior to the start of a memory access. | 6 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to display apparatus and display method for performing displaying of an image using picture elements or “pixels” as disposed in a matrix fashion. In particular, the invention relates to a liquid crystal display device and EL display device of the active matrix type.
[0003] 2. Description of the Related Art
[0004] Recently, the technology has been rapidly developed for fabrication of semiconductor devices with a semiconductor thin film being formed on a glass substrate of low cost, such as for example thin-film transistors (TFTs). The reason for this is that the needs for liquid crystal display devices of the active matrix type are increasing more and more.
[0005] The active-matrix type liquid crystal display device is such that TFTs are disposed respectively in several tens or several millions of pixel regions that are disposed in a matrix manner, which TFTs have their switching functions to control electrical charge carriers exiting from or entering to a respective one of pixel electrodes.
[0006] [0006]FIG. 1 shows a configuration of a liquid crystal display device of the active matrix type in the prior art. A shift register and buffer circuitry are typically called the “peripheral driver circuit” in general; in the recent years, this is integrally formed on the same substrate together with an active matrix circuit.
[0007] Disposed in the active matrix circuit are thin-film transistors which utilize amorphous silicon as formed on a glass substrate used.
[0008] A configuration has also been known wherein quartz is utilized as the substrate while employing a polycrystalline silicon film for fabrication of such thin-film transistors. In this case both the peripheral driver circuit and active matrix circuit will be constituted from those thin-film transistors formed on the quartz substrate.
[0009] In addition, a thin-film transistor fabrication technology is also known which makes use of a crystalline silicon film on a glass substrate by utilizing laser anneal techniques or the like. Use of this technology may enable integration of the active matrix circuit and its associated peripheral driver circuit on the glass substrate.
[0010] In the configuration shown in FIG. 1A, an image signal being supplied to an image signal line is selected at a timing as indicated by FIG. 1B in response to a signal from a shift register circuit (horizontal scanning shift register) of a source line side driver circuit. And, certain image signal will be supplied to a corresponding source signal line.
[0011] The image signal which was supplied to the source signal line is then selected by the thin-film transistor of a pixel to be written into a specified pixel electrode.
[0012] The pixel thin-film transistor is operable in response to a selection signal that is supplied via a gate signal line from a shift register (vertical scanning shift register) of a gate line side driver circuit not shown herein.
[0013] The above operation will be recurrently carried out with the setting of appropriate timings determinable depending on a signal from the shift register of the source line side driver circuit and a signal from the shift register of the gate line side driver circuit to thereby sequentially write information into respective pixels of the matrix shape.
[0014] After completion of writing of image information corresponding to a single screen, image information is then written for the next screen. In this way, displaying of images will be performed in a sequential order. Generally, such writing of this one-screen information is repeated for thirty times or alternatively sixty times per second.
SUMMARY OF THE INVENTION
[0015] In recent years, as the information amount increases rapidly, an attempt has been made to attain an increase in display capacity as well as an increase in precision of display image resolution. Here, some major examples of the display resolution standards as generally employable in computers will be indicated along with pixel numbers and standard titles.
Pixel Number (Width × Height) Name of Standard 640 × 400 EGA 640 × 480 VGA 800 × 600 SVGA 1024 × 768 XGA 1280 × 1024 SXGA
[0016] Today, even in the field of personal computers, software program packages have become widely available which perform a plurality of display operations different in nature from one another on the display screen; accordingly, a shift has been made to those display devices which are higher in display resolution than VGA and SVGA standards to accommodate the XGA and SXGA standards.
[0017] Furthermore, the prescribed liquid crystal display devices of high display resolution have also been employed for use in displaying television broadcast signals other than displaying of data signals in such personal computers.
[0018] As is well known, the currently available television signals may generally be classified into several groups which are based on the NTSC scheme, PAL scheme, and SECAM scheme. The NTSC television scheme has the degree of image resolution which is 525 in scanning-line number (effective scan line number is approximately 480). The PAL and SECAM schemes are 625 in scan line number (effective scan line number is 576).
[0019] In cases where an image based on television signals of the NTSC scheme or PAL scheme or alternatively SECAM scheme is to be visually indicated on a liquid crystal display device that accommodates the SVGA or XGA or SXGA standard stated supra, it will be required that an image non-display section (image-absent area on the screen) be provided due to a difference in resolution among them.
[0020] Now refer to FIGS. 2A and 2B. FIGS. 2A and 2B are schematical diagrams of liquid crystal display devices of the peripheral driver circuit integration type that are designed to accommodate the XGA standard. In FIG. 2A, reference numeral 201 is a source side driver circuit. 202 is a gate line side driver circuit. 203 is a TFT active matrix circuit section. In FIG. 2B numeral 207 is a sourceside driver circuit. 208 is a gate line side driver circuit. 209 is a TFT active matrix circuit section.
[0021] In the case of displaying an image based on a television signal of the PAL scheme on the liquid crystal display device accommodating the XGA standard, an image display section 204 and image non-display sections 205 and 206 are required as shown in FIG. 2A.
[0022] Alternatively, in the case of displaying an image based on a television signal of the NTSC system on the liquid crystal display device accommodating the XGA standard, a display section 210 and its surrounding image non-display section 211 are required as shown in FIG. 2B.
[0023] It will be desirable that the image non-display sections 205 , 206 and 211 be designed to display the complete black color in order to maximally enhance a visual difference from the image display sections 204 and 210 .
[0024] In the related art an attempt has been made to let the image non-display sections be colored in block in the way described above. However, the related art approach was difficult in achievement of such completely black-colored display in the image non-display sections. As a result, a decrease in quality has taken place.
[0025] As another method for displaying an image represented by a television signal on a liquid crystal display device that accommodates the XGA standard, a method is known which is for inputting the television signal to the driver circuit of the liquid crystal display device after acquiring or “downloading” to an associative personal computer and then converting and processing to a specific signal that corresponds in format to the XGA standard. In this case a separate device or circuit should additionally be required for conversion and processing of the television signal. Further, signal attenuation or degradation can occur due to the fact that the television signal must pass through such extra device or circuit, which would result in a decrease in image quality.
[0026] In accordance with one preferred practicing form of the present invention, a display device is provided which at least includes a plurality of TFTs, a signal generation means for generating a signal for use in determining the operation timing of said plurality of TFTs, a write control means for controlling outputting of said signal for determination of the operation timing, a means for outputting an externally supplied image signal to said TFTs on the basis of said signal for determination of the operation timing, and a display means for displaying an image based on said image signal, wherein said image signal is such that one is selected from among a plurality of image standards, wherein said display means has an image display section and an image non-display section for execution of displaying operations in a plurality of image standards, and wherein said write control means is operable to control the ratio of said image display section to said image non-display section of said display means. This may attain the foregoing objective.
[0027] Said image non-display section may be designed to display the color black.
[0028] It may also be arranged in a way such that said signal generation means is a shift register circuit while the operation of said shift register circuit is kept unchanged even when said image standard is changed.
[0029] Said image standard may be one selected from the group consisting of a television signal and a data signal from a computer.
[0030] In accordance with another practicing form of the present invention a display device is provided which at least comprises: an active matrix substrate which at least has a source line side driver circuit at least including a shift register circuit and a source line side write control circuit plus a switching circuit, a gate line side driver circuit at least including a shift register circuit and gate line side write control circuit, at least one TFT as disposed at a location in close proximity to an intersection between said source line and said gate line; an opposite substrate that oppose said active matrix substrate; and a display medium which is held between said active matrix substrate and said opposite substrate having its optical response as controlled by a voltage applied thereto, wherein said switching circuit is controlled by a signal from said source line side write control circuit while allowing an image signal as selected from among a plurality of image standards to be output to said source line and also causing a signal from said gate side write control circuit to be output onto a gate line. This may also attain the objective stated supra.
[0031] In the display device said display section for displaying said image signal may include an image display section and an image non-display section.
[0032] Said image non-display section may be designed to display the color black.
[0033] Said image standard may be either one of a television signal and a data signal from a computer.
[0034] Said display medium with its optical response as controllable by said voltage application may be either one of a liquid crystal device and an electro-luminescence device.
BRIEF DESCRIPTION OF THE DRAWINGS
[0035] [0035]FIGS. 1A and 1B are schematical diagrams of prior art liquid crystal display device of the active matrix type.
[0036] [0036]FIGS. 2A and 2B are diagrams for explanation of image non-display sections when displaying an image based on a television signal on a display device that accommodates the XGA video standard.
[0037] [0037]FIG. 3 is a schematical diagram of an active-matrix type liquid crystal display device in accordance with the present invention.
[0038] [0038]FIG. 4 is a diagram showing a configuration of a source line side driver circuit of the active-matrix type liquid crystal display device embodying the present invention.
[0039] [0039]FIG. 5 is a diagram showing a configuration of a gate line side driver circuit of the active-matrix liquid crystal display device embodying the invention.
[0040] [0040]FIG. 6 is a timing chart of the source line side driver circuit of the liquid crystal display device of this invention.
[0041] [0041]FIG. 7 is a timing chart of the gate line side driver circuit of the liquid crystal display device of this invention.
[0042] [0042]FIGS. 8A to 8 D are diagrams showing some major process steps in the manufacture of the active-matrix type liquid crystal display device of this invention.
[0043] [0043]FIGS. 9A to 9 C are diagrams showing some major process steps in the manufacture of the active-matrix liquid crystal display device of this invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0044] In this part of a detailed description of embodiment, an explanation will be given of a liquid crystal display device which may accommodate the XGA video-display standard. The liquid crystal display device in accordance with this embodiment of the invention is capable of executing display operations of images of a television signal (NTSC signal) Note that in this embodiment, the standards of television signals and data signals from computers will be called the “image standards”.
[0045] First refer to FIG. 3. FIG. 3 is a schematical circuit diagram of the liquid crystal display device embodying the invention. A source side driver circuit 301 has a shift register circuit 302 , a write control circuit 303 , and a switching circuit 304 . Also, a gate line side driver circuit 305 has a shift register circuit 306 and a write control circuit 307 .
[0046] A display section 308 has a TFT active matrix circuit with an array of 1024×768 pixels. The 1024×768 pixel active-matrix circuit is added with certain symbols such as (0,0), (1,0) and the like. In this embodiment these pixels will be called by such symbols (0,0), (1,0) and so on.
[0047] The source side driver circuit 301 is operable to supply a signal or signals to source lines s 0 to s 1023 of those TFTs that constitute the display section 308 . Also, the gate line side driver circuit 305 supplies signals to gate lines g 0 -g 767 of TFTs constituting the display section 308 .
[0048] Each pixel of the display section 308 is such that a liquid crystal layer is disposed as a display medium between an electrode connected to the drain electrode of a TFT and an electrode opposing the former—say, opposite electrode.
[0049] A VIDEO signal is input from the outside to the switching circuit 304 .
[0050] See FIG. 4, which shows one exemplary circuit configuration of the source side driver circuit in this embodiment. The shift register circuit 302 is configured from a plurality of flip-flop circuits. The reference character “SP” adhered to a signal as input to the shift register circuit is an abbreviation of “start pulse”—inputting this start pulse signal permits the operation of the shift register to get started at a specified timing. In addition, the reference character “CLK” representative of a signal being input to the shift register circuit is an abbreviation of a “clock signal,” which is to be input to the shift register at an appropriate timing. This shift register circuit 302 has a function of supplying a signal or signals for use in determining the operation timing to circuitry which corresponds to a source signal line. In this embodiment, output signals x 0 to x 1023 of the shift register circuit 302 are input to the write control circuit 303 .
[0051] As shown in FIG. 4, the write control circuit 303 consists essentially of a plurality of AND circuits. Input to the write control circuit 303 are the output signals x 0 -x 1023 of shift register circuit 302 along with an “EN” signal. In response to this EN signal, the output signals x 0 -x 1023 of the shift register are supplied to the switching circuit 304 so that the signal for determination of the operation timing is selectively supplied to a circuit corresponding to the source signal line.
[0052] The switching circuit 304 is constituted from a plurality of switching elements, to which the external VIDEO signal and an output of the write control circuit 303 are input. When the output of write control circuit 303 is at the high level “Hi,” the VIDEO signal is supplied to the source lines s 0 to s 1023 .
[0053] Turning now to FIG. 5, this diagram shows one exemplary circuitry of the gate line side driver circuit as used in this embodiment. The shift register circuit 306 includes plural flip-flop circuits. In FIG. 5 also, the reference character “SP” refers to a start pulse whereas “CLK” stands for the clock signal. In this embodiment also, output signals y 0 to y 767 of the shift register are input to the write control circuit 307 .
[0054] As shown in FIG. 5, the write control circuit 307 is made up from a plurality of AND circuits. Input to the write control circuit 307 are the output signals y 0 -y 767 of shift register circuit 306 along with the EN signal. In the gate line side driver circuit also, the shift-register output signals y 0 -y 767 are selectively supplied to the gate lines go to g 767 in response to receipt of the EN signal.
[0055] The liquid crystal display device of the present invention makes use of a normally-black display mode in which black-colored display is done when no voltages are applied to the liquid crystal layer. Hence, those TFTs of the display section 308 which are selected upon receiving of the signals of source lines s 0 -s 1023 and signals of gate lines g 0 -g 767 are turn on forming an image.
[0056] It should be noted that the illustrative configuration of the source side driver circuit and gate line side driver circuit of this embodiment is one preferred embodiment only. In the source side or gate side peripheral circuitry, a memory circuit and buffer circuit as well as another switching circuit or the like may be disposed when required. Note also that other circuits may be disposed as needed.
[0057] In this embodiment, in cases where all of the pixels (0,0) to (1023, 767) are to be subjected to displaying, the EN signal which is input to the write control circuits 303 and 307 is kept at the “Hi” level without regard to the timing thereof. With such an arrangement the output signals x 0 -x 1023 of shift register circuit 302 are sequentially input to the switching circuit 304 whereas the output signals y 0 -y 767 of shift register circuit 306 are sequentially input to the gate lines g 0 -g 767 . In the source side driver circuit the VIDEO signal is output in response to receipt of the output signals x 0 -x 1023 being input to the switching circuit 304 , and is in turn input to the source lines s 0 -s 1023 in a sequential way.
[0058] Those TFTs of the display section 308 which are selected by the signals as supplied to the source lines s 0 -s 1023 and gate lines g 0 -g 767 are then rendered operative forming an image.
[0059] Next, consider the case where one certain pixel or certain pixel region alone is the object to be displayed. By way of example, one exemplary case will be explained of displaying an image represented by a television signal (NTSC signal) on the liquid crystal display device of this embodiment. In this embodiment, assume that the aspect ratio when displaying images using such NTSC signal is “16:9.”
[0060] The liquid crystal display device of this embodiment is 1024×768 in pixel number and thus accommodates the XGA standard. Therefore, where an image of an NTSC signal (effective scan-line number is 480) is displayed on the liquid crystal display device of this embodiment, one or more image non-display regions should be required. In this case it is desirable that such image non-display regions be displayed in pure black. An explanation will be given of a display method for displaying the image non-display region or regions in black while also displaying an image of NTSC signal.
[0061] Where an NTSC-signal image is to be displayed on the liquid crystal display device of this embodiment (XGA standard), such image is displayed at those selected pixels (85, 144) to (938, 623). The remaining pixels are forced to display no images thereat and are driven to visually indicate a pure black background in the so-called “black display” mode.
[0062] [0062]FIGS. 6 and 7 show timing charts in this case. With regard to certain source lines and gate lines of such “free-from-the-display” pixels, i.e. lines s 0 -s 84 , s 939 -s 1023 , g 0 -g 143 and g 624 -g 767 , the EN signal being input to the write control circuits 303 and 307 is controlled so that the output signals potentially drop down at the low level “Lo.”
[0063] It may be apparent from viewing FIG. 6 that the EN signal being input to the write control circuit 303 rises in potential up to the “Hi” level only upon occurrence of coincidence in timing with those signals x 85 -x 938 from the shift register; at this time, the high signal “Hi” is output to the switching circuit 304 . Upon inputting of this “Hi” signal the switching circuit operates to sequentially output the VIDEO signal to the source lines s 85 -s 938 .
[0064] Turning now to FIG. 7, the EN signal as input to the write control circuit 307 is at the “Hi” level only upon occurrence of coincidence in timing with those signals y 144 -y 623 from the shift register, thus sequentially outputting the signal to the gate lines g 144 -g 623 .
[0065] Executing the above operation may cause signals to output only to the selected source lines s 85 -s 938 and gate lines g 144 -g 623 , which in turn makes it possible to let any desired pixels turn on thus enabling the NTSC signal image to be displayed thereon. Further, since no signals are output to the remaining pixels that are not operatively related to such image displaying, it becomes possible to attain complete black display therefor.
[0066] A fabrication process of the liquid crystal display device of this embodiment will be explained below. It is noted that while the liquid crystal display device of this embodiment is designed to be of the reflection type, the principles of the present invention may also be applied to those liquid crystal display devices of the pass-through or transmission type.
[0067] See FIG. 8A. First of all, an undercoat film (not shown) is formed on the surface of a substrate 801 . The substrate 801 may be a glass substrate, or alternatively an optically transparent substrate such as for example a quartz substrate or any equivalents thereto.
[0068] Then, active layers 803 - 805 are formed each of which is made of a crystalline silicon film. Note here that the active layers 803 and 804 will be later used to constitute a TFT of driver circuitry whereas the active layer 405 constitutes a TFT of pixel matrix circuitry at a later stage of fabrication.
[0069] The aforesaid crystalline silicon film may be directly formed by low-pressure thermal CVD techniques or alternatively be formed by crystallization of an amorphous silicon film. In this embodiment an amorphous silicon film of typically 10 to 75 nm thick (preferably, 15 to 45 nm) is crystallized by use of the technique which has been disclosed in the Published Unexamined Japanese Patent Application No. 7-130652. The active layers 803 - 805 are those which were formed in a way such that a crystalline silicon film as obtained by the technique disclosed in the above Japanese Application document was then patterned into several “island” portions.
[0070] After formation of the active layers 803 - 805 , a silicon oxide film is formed to a predetermined thickness of 120 nm, as a gate insulation film 806 . This gate insulation film 806 may be a silicon oxide-nitride SiO x N y or silicon nitride or alternatively a multi-layered film consisting essentially of these materials laminated.
[0071] Next, a metallic film which is not depicted but is mainly made of aluminum is formed and then subject to a patterning process thus forming an original form or “master mold” of a later-defined gate electrode and gate lead pattern. At this step the fabrication technique taught by PUJPA No. 7-135318. Use of such technique of this Japanese Application document results in formation of porous anode-oxidized or “anodized” oxide films 807 - 809 and dense anodized films 810 - 812 plus gate electrodes 813 - 815 shown in FIG. 8B as well as gate lead lines (not shown). Note that the gate electrodes and gate leads will be referred to as the “first lead lines” hereinafter.
[0072] It is to be noted that the material of the gate electrodes or gate leads may not exclusively be limited to the one essentially comprised of aluminum and may be replaced with any other anodizable materials such as for example tantalum, molybdenum, tungsten and the like. Additionally, the gate electrodes may alternatively be made of a crystalline silicon film with one specified conductivity type added thereto.
[0073] Next, the gate insulating film 806 is etched by dry etching techniques with the gate electrode 813 - 815 and porous anodized oxide films 807 - 809 being as a mask therefor, thereby forming gate insulating films 816 - 818 . And thereafter, the porous anodic oxide films 807 - 809 are removed away. In this way the resulting structure is such that the gate oxide films 816 - 818 are exposed at the end portions thereof (FIG. 8C).
[0074] Next, impurity ions are doped through two separate process steps for adding thereto the N-conductivity type. In this embodiment the first impurity doping process is carried out upon application of a high acceleration voltage to thereby form more than one n − region. At this time the impurity ions might be doped into not only the exposed active layer surfaces but also certain part underlying the end portions of the exposed gate oxide films due to the fact that the acceleration voltage applied is high in potential. Further, the second impurity doping process is then performed upon application of a relatively low acceleration voltage thus defining one or more n + regions. When this is done, since the acceleration voltage used is low in potential, the gate oxide films function as a mask.
[0075] Through the foregoing process steps, there are formed a source region 819 , drain region 820 , lightly-doped impurity region 821 and channel formation region 822 which are those impurity regions of an N-channel type TFT constituting a CMOS circuit of the driver circuit. Also defined are a source region 823 , drain region 824 , lightly-doped impurity region 825 and channel formation region 826 of an N-channel type TFT which are those impurity regions for constituting a pixel TFT (FIG. 8C).
[0076] It must be noted that in the state shown in FIG. 8C, a P-channel type TFT constituting the CMOS circuit is the same in structure as the N-channel type TFT.
[0077] Next, a resist mask 827 is provided overlying the N-channel type TFT; then, an impurity ion doping process is executed for adding thereto the P type conductivity. This process is also subdivided into two separate steps as in the prior impurity dope process stated above, to thereby form a source region 828 , drain region 829 , lightly-doped impurity region 830 and channel formation region 831 of a P-channel type TFT which also constitutes the CMOS circuit (FIG. 8D).
[0078] After obtaining the structure shown in FIG. 8D, thermal processing is done by furnace anneal, laser anneal or lamp anneal techniques for activation of the impurity ions as doped into the active layers. At this time, it may also be possible to cure any possible damages of the active layers as a result of such doping of impurity ions thereinto.
[0079] Next, refer to FIG. 9. After completion of the fundamental or basic part of the TFT through the prescribed process steps, a silicon oxide film is formed to a thickness of 0.3 to 1 μm, as a first interlayer dielectric layer 832 ; then, source lead lines 833 - 835 and drain lead lines 836 , 837 are formed through contact holes (these leads will be referred to as the “second lead lines” hereinafter). The first interlayer dielectric film 832 may alternatively be made of an organic resin film.
[0080] Next, a second dielectric layer 838 is formed to a thickness of 0.5 to 3 μm. In this embodiment the second interlayer dielectric film 838 was made of polyimide. Note here that the second interlayer dielectric film 838 may alternatively be made of acryl, polyamide, polyimide-amide, or any equivalent thereof.
[0081] Next, a black mask 839 is formed on the second interlayer dielectric film 838 to a thickness of 100 nm, which mask is comprised of a chosen film that has light-shield or opacity. In this embodiment the black mask 839 consists of a titanium film; alternatively, the same may be made of a resin film containing therein black pigments.
[0082] After formation of the black mask 839 a third interlayer dielectric film 840 is then formed to a thickness of 0.1 to 0.3 μm. In this embodiment the third interlayer dielectric film was comprised of a silicon oxide film; however, the film may alternatively be made of either a silicon nitride film or organic resin film, or still alternatively, a multilayered lamination structure of these films.
[0083] And, contact holes are formed in the second interlayer dielectric film 838 and the third interlayer dielectric film 840 to thereby form a pixel electrode 841 . At this time an auxiliary capacitance may be formed in a certain region in which the black mask 839 and pixel electrode 841 overlap each other. In this embodiment the pixel electrode 841 is made of a chosen material as essentially comprised of aluminum.
[0084] It should be noted that the pixel electrode 841 is made of one of high-reflectivity materials. In this embodiment the aluminum-based material was employed; however, titanium, an alloy of aluminum and silicon, and alloy of aluminum and titanium, or an alloy of aluminum and scandium or the like may be used alternatively. Or still alternatively, the pixel electrode 841 may be formed to have a lamination structure of such plural materials.
[0085] Next, thermal processing is carried out in the atmosphere containing hydrogen therein thus forcing any residual unpaired coupling hands of the active layers to terminate with hydrogen. Doing this hydrogenization processing may result in a noticeable increase in characteristic of TFTs fabricated.
[0086] Thereafter, a dielectric film is formed on the upper part of the resultant structure; then perform CMP (Chemical Mechanical Polish) processing. In this embodiment a polyimide film was employed as this dielectric film. It is preferable that the organic resin film for use as the aforesaid dielectric film is made of polyamide, polyimide-amide, acryl or the like.
[0087] As a result of the above-mentioned CMP process step, dielectric films 842 , 843 are formed as shown in FIG. 9B. Very importantly, the dielectric films 842 , 843 and pixel electrode 841 are planarized on the upper part thereof.
[0088] In the way described above, an active matrix substrate including the pixel matrix circuit and driver circuitry of the liquid crystal display device of the reflection type is thus fabricated.
[0089] Next, an orientation film 844 is formed on the upper surfaces of the uppermost layers (pixel electrode 841 and dielectric films 842 , 843 ) of the resulting active matrix substrate. Also, an opposite substrate is prepared on which an opposing electrode 845 and an orientation film 846 are formed. Note that a color filter may be provided to the opposite substrate 847 where necessary.
[0090] And, a seal material (not shown) is printed on the side of the opposite substrate, whist spacers (not shown) are distributed on the side of the active matrix substrate for lamination of the two substrates together. Furthermore, a liquid crystal material is injected into the inside space defined between the two substrates; then, a seal material (not shown) is used to seal the same. In this way a liquid crystal layer 848 is stably sealed between the opposite substrate and the active matrix substrate.
[0091] After executing the foregoing process steps the intended active-matrix liquid crystal display device is completed as shown in FIG. 9C. It is noted that as shown in FIG. 9C, incident light undergoes reflection onto the pixel electrode 441 permitting an image to be displayed.
[0092] According to the liquid crystal display device of this embodiment, it is possible by appropriately controlling the EN signal as input to the write control circuits to limit the area for use in displaying images while at the same time enabling any remaining pixels that do not relate to such image-displaying operation to be set in the complete or “pure” black display mode.
[0093] As a consequence, according to the liquid crystal display device and its associated display method of this embodiment, it becomes possible to successfully display television signals (NTSC signals) on the screen of the liquid crystal display device which accommodates the XGA video standard.
[0094] It should be noted that although in the illustrative embodiment the AND circuits were used to attain the circuitry for constituting the write control circuits, any other circuits are employable as far as these are capable of controlling an input signal from the shift register upon receiving of an input signal as externally supplied thereto.
[0095] It should also be noted that while in this embodiment the case has been described where images based on the NTSC signal are to be displayed on the liquid crystal display device which accommodates the XGA standard, the display method of the present invention may also be applicable to several cases where images represented by television signals such as NTSC signals and PAL signals are displayed on those liquid crystal display devices accommodating the SVGA and SXGA standards and moreover any other video standards.
[0096] Further, while any specific detailed description was not presented relative to this embodiment, in the case of displaying color images, a color filter may be provided. In particular, where the display method of the present invention is adapted for use with those liquid crystal display device of the projection type, a set of three similar liquid crystal display devices each corresponding to the embodiment device stated supra are employed while causing them to display red, blue and green video images which are then projected onto an associated screen for optical superimposition thereof to thereby attain a superior color image displaying scheme.
[0097] Furthermore, although in this embodiment one specific case of using the liquid crystal as its display medium has been explained, the display method for the display device in accordance with the present invention may also be applicable to those liquid crystal display devices of what is called the “polymer distribution” type having a mixture layer of liquid crystal and polymer in combination. Alternatively, the display method for the display device of this invention may be applied to any types of display devices as equipped with any kinds of display media of the type which may be modulated in optical characteristic in response to a voltage applied thereto. One example is a display device with an electro-luminescence element as its display medium.
[0098] It should further be noted that in the liquid crystal display device of this embodiment, it is possible by controlling the EN signal to switch between the display of signals from personal computers and the display of television signals. This signal switching may be done by users as needed. Or alternatively, the display device may be designed such that a setup is made, when shipping using dip switches, causing the display device to display specific images based on preselected types of signals. Even in this case, display devices of the same type may be manufactured since no alterations are required to such display devices.
[0099] According to the displaying method for use with the liquid crystal display device of the present invention, it is possible for a display device accommodating different video standards to display images based on television signals. | A display device for displaying images based on signals of different standards is disclosed.
In a display device of the active matrix type, write control circuits as provided in a source side driver circuit and a gate line side driver circuit are operable to selectively supply output signals of shift registers to a source line and a gate line. Whereby, it becomes possible to render the non-display section of an image clearer or visually distinguishable, which in turn leads to capability of successful execution of images with excellent quality. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates generally to digital communication systems. More particularly, this invention relates to a method and apparatus for echo cancellation in full duplex asymmetric communication systems.
2. Description of the Related Art
Communication systems are very common in today's society. These systems have evolved from devices that provide simple half-duplex data transmissions to sophisticated full-duplex systems providing voice, data, and video transmission and reception. Half-duplex communication commonly refers to the communication of information between a transmitter and a receiver in one direction at a time. On the other hand, full-duplex communication commonly refers to the communication of information between the transmitter and receiver in both directions at the same time, i.e., simultaneously. However, with sophistication comes added complexity which often necessitates corrective measures. One complexity that is associated with fill-duplex systems is a phenomenon known as “echo”. The production of echo in a full-duplex system is often attributed to leakage of at least a portion of a transmitted signal into an unintended receiver, such as a receiver portion of a transceiver or a co-located receiver.
FIG. 1 shows a functional block diagram of an exemplary modem system. At a near-end of the system 100 a is a transmitter 110 a and a receiver 120 a . The transmitter 110 a and receiver 120 a are isolated or separated from each other by a hybrid 150 a . As is well known in the art, a hybrid may be defined as a circuit that routes signals from one source (e.g., the transmitter 110 a ) to a desired output port, while preventing the signals from passage to an unintended destination (e.g., the receiver 120 a ). The transmitter 110 a includes a digital modulator 112 a that modulates information signals onto a carrier signal in preparation for transmission over a communication medium 170 . The communication medium 170 may be a wired (e.g., telephone lines) and/or a wireless (e.g., airwaves) medium. The transmitter 110 a further includes a digital-to-analog converter (DAC) 114 a , which converts digital signals received from the digital modulator 112 a into analog signals prior to transmission over the medium 170 . The digital signal stream has a sampling rate of “fs”. Similarly, the receiver 120 a includes an analog-to-digital converter (ADC) 124 a , which converts analog signals received from the communication medium 170 into digital signals. The receiver 120 a further includes a digital demodulator 122 a that demodulates the digital signals from the carrier signal for further processing at an ultimate destination (not shown in this figure), e.g., a computer, television, or other application device.
The far-end portion of the system 100 b comprises a mirrored-structure of the near-end portion of the system 100 a . More particularly, the system 100 b further comprises a transmitter 110 b and a receiver 120 b . The transmitter 110 b and receiver 120 b are isolated or separated from each other by a hybrid 150 b . The transmitter 110 b includes a digital modulator 112 b that modulates information signals onto a carrier signal for transmission over a communication medium 170 . The transmitter 110 b further includes a digital-to-analog converter (DAC) 114 b , which converts digital signals received from the digital modulator 112 b into analog signals prior to transmission over the medium 170 . Similarly, the receiver 120 b includes an analog-to-digital converter (ADC) 124 b , which converts analog signals received from the communication medium 170 into digital signals. The receiver 120 b further includes a digital demodulator 122 a that demodulates the digital signals from the carrier signal for further processing at an ultimate destination (not shown in this figure), e.g., a computer.
In practice, at least a portion of signals transmitted from the near-end transmitter 110 a leak through the hybrid 150 a into the near-end receiver 120 a . This leakage contaminates the near-end receiver 120 a in the form of an echo by mixing with or superimposing signals received from the far-end transmitter 110 b . Thus, this superimposition causes interference by the echo signal with the intended information signals. The same is true for the far-end transceiver.
To circumvent such echo in full duplex systems, one of two methods may be applied. The first method is frequency division multiplexing (FDM), which may be defined as a multiplexing technique that uses different frequencies to combine multiple streams of signals for transmission over a communications medium. More particularly, forward and reverse streams of signals travelling in opposite directions occupy different portions of the frequency spectrum, with the effect that they can be easily separated in frequency at the receivers through a variety of signal processing techniques. FDM is not bandwidth efficient because it does not make full use of available bandwidth. The second method is echo cancellation, which allows forward and reverse signals to occupy overlapping frequency bands. A copy of the echo signal is reconstructed and subsequently subtracted at the affected receiver. Current echo cancellation techniques have been burdened in many applications by too much computational power and inferior speed performance rendering them undesirable.
Therefore, there is a need in the communications technology for a method and system that reduces computational requirement of echo cancellation. The method and system should be adaptable using common efficient and stable techniques without adding implementation hindrances.
SUMMARY OF THE INVENTION
The invention provides a method of canceling echo signals in a communication system. The communication system comprises a receiver that receives the echo signals at a first data rate, and a transmitter that is configured to transmit signals at a second data rate. In one embodiment, the method comprises increasing the data rate of the transmitted signals from the second data rate to a higher data rate. The method further comprises estimating echo signal components based at least in part on the higher data rate signals. The method further comprises matching the data rate of the estimated echo signal with the first data rate of the receiver. In another embodiment, the method comprises filtering the transmitted signals to substantially remove frequency components above a cut-off frequency that is equivalent to at least one-half of the predetermined data rate. The method further comprises reducing the data rate of the filtered signals from the predetermined data rate to a lower data rate. The method further comprises estimating echo signal components based at least in part on the filtered signals.
The invention further provides a system for canceling echo signals received by a receiver that is configured to operate at a first data rate. The echo signals originate from a transmitter that is configured to transmit signals at a second data rate. In one embodiment, the system comprises a filter that is configured to substantially remove from the transmitted signals frequency components above a cut-off frequency that is equivalent to at least one-half of the first data rate. The system further comprises a decimator that is configured to reduce the data rate of the filtered signals from the second data rate to a lower data rate. The system further comprises an echo canceler that is configured to estimate echo signal components based at least in part on the filtered signals at the lower data rate. In another embodiment, the system comprises a first upsampler that is configured to increase the data rate of the transmitted signals from the second data rate to a higher data rate. The system further comprises an echo canceler that is configured to estimate an echo signal based at least in part on the upsampled signals. The system further comprises a second upsampler that is configured to match the data rate of the estimated echo signal with the first data rate of the receiver.
In yet another embodiment, the system comprises means for filtering the transmitted signals to substantially remove frequency components above a cut-off frequency that is equivalent to at least one-half of the predetermined data rate. The system further comprises means for reducing the data rate of the filtered signals from the predetermined data rate to a lower data rate. The system further comprises means for estimating echo signal components based at least in part on the filtered signals. In yet another embodiment, the system further comprises means for increasing the data rate of the transmitted signals from the second data rate to a higher data rate. The system further comprises means for estimating echo signal components based at least in part on the higher data rate signals. The system further comprises means for matching the data rate of the estimated echo signal with the first data rate of the receiver.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other aspects, features, and advantages of the invention will be better understood by referring to the following detailed description, which should be read in conjunction with the accompanying drawings, in which:
FIG. 1 is a functional block diagram of an exemplary modem system.
FIG. 2 is a functional block diagram of a near-end modem system in accordance with the invention.
FIG. 3 is a functional block diagram of a far-end modem system in accordance with the invention.
DETAILED DESCRIPTION OF THE INVENTION
The following description is not to be taken in a limiting sense, but is made merely for the purpose of describing the general principles of the invention. The scope of the invention should be determined with reference to the claims.
FIG. 2 shows a functional block diagram of one embodiment of a near-end modem system 200 in accordance with the invention. The near-end system is sometimes referred to as a remote-terminal (RT) system, whereas a far-end system (see FIG. 3 ) is sometimes referred to as a central office (CO) system. In this embodiment, the RT system 200 comprises an asymmetric digital subscriber loop (ADSL) system which conforms to ADSL standard promulgated by the American National Standard Institute (ANSI) in T1.413-1998, which is incorporated in its entirety by reference. The communication channel from the RT system 200 to the CO system is commonly referred to as an “upstream” channel, and that from the CO system to the RT system 200 is commonly referred to as a “downstream” channel.
As shown in FIG. 2 , the RT system 200 comprises a transmitter 210 that is configured to transmit signals over a communication medium 270 via a hybrid 250 . The RT system 200 further comprises a receiver 220 that is configured to receive signals over the communication medium 270 via the hybrid 250 . The RT system 200 further comprises an echo canceler (EC) subsystem 230 that is configured to cancel or minimize echo signals. As shown in FIG. 2 , the echo path is represented pictorially by an echo channel 252 , and it is understood that such pictorial representation is intended to describe the general direction of echo flow and, thus, is not intended to describe the physical path of echo signals. Each of these subsystems is described in detail below.
The transmitter 210 comprises a digital modulator 212 that receives and modulates a digital information signal onto a carrier signal. The output of the digital modulator 212 is a modulated discrete-time sequence signal having a data or sampling rate of fs/K, where fs is the downstream transmission data or sampling rate and K is a constant integer. The modulated discrete-time sequence signal is fed into an up-sampler 216 to be upsampled by a factor K. Upsampling by a factor K of a discrete-time sequence signal may be accomplished mathematically by inserting K-1 sequence points with zero amplitude between each of the samples or sequence points of the modulated sequence, and increasing the sampling rate by a factor of K. Upsampling is basically the reverse process of downsampling.
In an ADSL system, the downstream sampling rate of transmitted signals is K times greater than that of the upstream sampling rate, where K=8. More particularly, the sampling rate of the downstream channel is typically about fs=2.208 MHz. The sampling rate of the upstream channel is typically about fs/8=276 kHz. Since, both the upstream and downstream channels are band-limited, the echo channel 252 is also band-limited. As will be appreciated and understood by those of ordinary skill in the art, a continuous-time signal may be sampled into a discrete-time sequence without a loss of information when the sampling rate (i.e., Nyquist frequency or sampling rate) is at least two times the highest frequency component of the original continuous-time signal. In this embodiment, it is desirable to sample signals of the echo channel 252 at a minimum rate possible (i.e., fs/K), so that the corresponding EC subsystem 230 uses a smaller number of tap weights than that of higher sampling rates. Ideally, the number of tap weights of the EC subsystem 230 is substantially equal to the number of discrete samples of the impulse response h(t) of the echo channel 252 . For a fixed duration of the impulse response h(t), the number of tape weights required by the EC subsystem 230 depends on the sampling rate. Thus, it is desirable to drive the EC subsystem 230 by an input signal having the least sampling rate possible.
As noted above, the sampling rate of the modulated signal (i.e., output of the digital modulator 212 ) is fs/K. Thus, the echo channel of such an ADSL system is band-limited to a frequency band that is one-half (½) of the sampling rate (i.e., fs/K) of the upstream channel. Accordingly, in one embodiment, the echo channel 252 is band-limited to fs/2K (e.g., 2.208 MHz/16=138 kHz), since a bandwidth of 138 kHz is sufficient for signals of the transmitter 210 . However, in practice the echo channel 252 may still have appreciable or significant energy in frequency bands that are greater than fs/2K. The presence of frequency components above fs/2K may hamper or reduce the accuracy of performance of the EC subsystem 230 that operates at a sampling rate of fs/K. Thus, it is desirable to introduce an additional band limiting filter (e.g., low pass filter) 218 into the echo path at the RT system 210 . Accordingly, the RT system 210 further comprises a band limiting filter 218 that is configured to attenuate echo signals having frequency components above fs(J/2K), where J is a positive integer less than K and K/J is also an integer. In one embodiment, it is desirable to select J=2, which yields an EC subsystem that is usually less than 100 taps long in ADSL implementation. The transmitter 210 further comprises a digital-to-analog converter (DAC) 214 which receives output signals from the band limiting filter 218 to convert digital signals to analog form for transmission. The DAC 214 feeds converted analog signals into a transmit filter 244 , which filters undesired frequencies from analog signals before transmission via the hybrid 250 to the communication medium 270 .
The receiver 220 comprises an anti-aliasing filter 248 that receives signals via the hybrid 250 from the communication medium 270 . The anti-aliasing filter 248 feeds its output signals, which are in analog form, into an analog-to-digital converter (ADC) 224 . The ADC 224 converts analog signals into a digital or discrete-time sequence at a sampling rate fs. The ADC 224 feeds its digitized sequence into a subtractor 246 and into the EC subsystem 230 for further processing.
The EC subsystem 230 comprises an echo canceler (EC) finite impulse response (FIR) filter 234 in the time-domain. In one embodiment, the EC FIR filter 234 may comprise a transversal filter. To provide an input signal having a sampling rate of fs(J/K) into the EC FIR filter 234 , the output signal of the digital modulator 212 is fed into an upsampler 232 that is configured to upsample the modulated signal by a factor J from its original sampling rate fs/K. The upsampler 232 outputs the upsampled signal with a sampling rate of fs(J/K). After proper training (see description below), the EC FIR filter 234 is configured to reconstruct from the upsampled signal a signal that is substantially identical to the echo signal, i.e., output signals of the ADC 224 having a sampling rate of fs, after being decimated by a factor K/J. Decimation by a factor of K/J may be accomplished mathematically by extracting every K/Jth sample from the digital sequence.
Pursuant to the ANSI standard, a predetermined period of time is dedicated to properly train the EC FIR filter 234 at the RT system 200 and CO system 300 . During such period, only one modem system (e.g., RT system 200 ) transmits signals while the other modem system (e.g., CO system 300 ) remains silent. Thus, any signals received by the transmitting system represent mainly echo signals. In this embodiment, the EC FIR filter 234 feeds the reconstructed echo signal into a subtractor 236 , which subtracts the reconstructed echo signal from the actual echo signal received from the decimator 238 . The subtractor 236 may generate an “error” signal which is fed back into the EC FIR filter 234 to dynamically adapt the EC FIR filter 234 to changing echo conditions. The dynamic adaptation of the EC FIR filter 234 may be necessary because of possible changes in impedance characteristics of the communication medium and variation in echo conditions from one installation to another. With a sampling rate of fs(J/K), the error signal may be used to update the EC FIR filter 234 using any variant of the family of least means square (LMS) adaptive algorithms. The adaptation may be used during the training period of the EC FIR filter 234 , or during full-duplex operation to track and compensate for any variations in echo channel characteristics.
Since echo signals have a limited bandwidth of fs(J/2K), the reconstructed echo signal of the EC FIR filter 234 may be interpolated by a factor of K/J to accurately represent the echo signals of the echo channel 252 at each sample point. Such interpolation may be carried out using multi-rate signal processing techniques. More particularly, interpolation by K/J may be accomplished by first upsampling the reconstructed echo signal by a factor of K/J using the upsampler 240 . In the frequency domain, upsampling causes the frequency band to shrink by a factor of K/J in frequency, and the shank frequency band is replicated (K/J-1) times in the frequency domain. Interpolation is accomplished by passing the upsampled signal through an interpolation (low pass) filter 242 that is configured to remove the replicated (K/J-1) frequency bands produced by the upsampler 240 . The output of the interpolation filter 242 is fed into a subtractor 246 , which subtracts the output of the interpolation filter 242 from output signals of the ADC 224 at a common sampling rate fs to cancel the echo signals. During full-duplex operation, the output of the subtractor 246 is fed into the digital demodulator 222 for demodulation in accordance with the implemented demodulation scheme.
FIG. 3 is a functional block diagram of the CO modem system 300 in accordance with the invention. As will be apparent from the following description, the CO system 300 is similar to the RT system 200 . More particularly, the transmit portion of the CO system 300 comprises a digital modulator 312 connected to a DAC 314 and a transmit filter 344 . The structure and operation of each of these transmitter components is substantially similar to its respective component in the transmitter 210 (FIG. 2 ). The receiver portion of the CO system 300 comprises an anti-aliasing filter 348 connected to an ADC 314 , which is configured to convert analog signals received from the RT system 200 over the communication medium 270 into digital form, i.e., discrete-time sequence. The ADC 314 forwards the discrete-time sequence to a band limiting (low pass) filter 318 to band limit received echo signals to fs(J/2K). The output of the band limiting filter 318 is fed into a decimator 316 to decimate the discrete-time sequence by a factor of K, thereby yielding an output discrete-time sequence having a data or sampling rate of fs/K. The output of the decimator 316 is fed into a subtractor 346 for further processing, as described below.
As described in connection with the RT system 200 , the CO system 300 also comprises an EC subsystem that is configured to cancel echo signals at the CO system 300 . As shown in FIG. 3 , the echo path is represented by an echo channel 352 . Because of the band limiting filter 318 and other band limiting effects inherent in ADSL systems, the echo channel 352 is practically band limited to fs(J/2K). Only the frequency portion of the transmit signal (from the digital modulator 312 ) that coincides with the bandwidth of the echo channel is expected to appear as echo at the receiver of the CO system 300 . Thus, frequency components of the transmit signal in the frequency band of 0-fs(J/2K) Hz are sufficient to reconstruct the echo signal by the EC subsystem. Accordingly, the EC subsystem comprises a decimation filter 342 that is configured to filter out frequency components outside fs(J/2K) of the transmit signal received from the digital modulator 312 . As will be understood by one of ordinary skill in the art, the normalized upper cut-off frequency in designing the decimation filter 342 is π/(K/J). The output of the decimation filter 342 is a discrete-time sequence having a sampling rate of fs that is fed into a decimator 340 . The decimator 340 decimates the filtered discrete-time sequence by a factor of K/J to produce a discrete-time sequence having a sampling rate of fs(J/K).
The output sequence of the decimator 340 is fed into an EC FIR filter 334 that is configured to reconstruct an echo signal based on the transmit signal of the digital modulator 312 . To compress the sampling rate from fs(J/K) down to fs/K, it is desirable to perform a decimation by a factor of J on the echo signal that is reconstructed by the EC 334 . Accordingly, the output of the EC FIR filter 334 is fed into a decimator 332 to decimate the reconstructed echo signal by a factor of J and provide a discrete-time sequence having a sampling rate of fs/K. The output of the decimator 332 , which represents the final reconstructed echo signal, is fed into the subtractor 346 , which removes the reconstructed echo signal from the output sequence of the decimator 316 , thereby canceling the echo signal produced by the echo channel 352 .
As discussed in connection with the EC FIR filter 234 , the output of the subtractor 346 may be used to produce an error signal to be fed back into the EC FIR filter 334 for adaptation. The error signal is used in an adaptation algorithm, such as one of the LMS-type algorithms known in the art. Since the error signal comprises a discrete-time sequence at a sampling rate of fs/K, the adaptive update in the LMS algorithm is carried out at the same rate of fs/K.
In light of the above description, it will be apparent to those of ordinary skill in the art to implement some or all of the components of the RT system 200 and CO system 300 using conventional software programming, dedicated hardware circuitry, or a combination of both. For example, the EC subsystems may be implemented using a programmable device, such as a microprocessor or an application specific integrated circuit (ASIC), that is programmed with instructions that performs the above-described functions.
In view of the foregoing, it will be appreciated that the invention overcomes the long-standing need for a method and system for efficiently canceling echo in modem systems, such as ADSL systems. The invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiment is to be considered in all respects only illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather by the foregoing description. All changes that fall within the meaning and range of equivalency of the claims are to be embraced within their scope. | A method and system for canceling echo signals originating from a transmitter at a predetermined data rate. The echo signals are received by a receiver at a different data rate. The echo system is configured to manipulate data rates of transmitted signals, and reconstruct echo signals for consideration by the receiver. In view of the band-limited nature of these echo signals, the invention intelligently reduces the computational complexity of reconstructing and canceling echo signals. | 7 |
PRIORITY
[0001] This application claims the benefit of priority to European application no. 02447219.3, filed Nov. 13, 2002, United Kingdom patent application no. 0228573.2, filed Dec. 9, 2002, and PCT application no. PCT/GB2003/004940, filed Nov. 13, 2003.
FIELD OF THE INVENTION
[0002] This invention relates to a commutator, to circuits containing such a commutator and to methods of energy conversion. Particularly, but not exclusively, the invention relates generally to nuclear energy conversion, electrolytic circuits, and cells and more specifically to porous flow through electrodes.
BACKGROUND
[0003] Many different types of electrolytic circuit and cells have been in use for many years and are currently in use for various applications from corrosion protection and material production which utilize electrolysis to batteries which are in everyday use which convert energy released from chemical reactions to electrical energy. Electrolysis cells utilizing porous flow through electrodes have been in use, for example, for the continuous analysis of liquid streams. All these techniques in this field in use so far make use of one or more of the following elements:
electrodes that provide an interface between an electrical circuit and an electrolyte normally with DC voltages being applied to them or DC voltages being generated between electrodes an electrolyte, that is a solution containing a number of ionic species a method of providing a steady continuous flow of electrolyte through or past an electrode or means of utilizing the flow of the electrolyte through or past an electrode—this commonly involves the use of porous flow through electrodes
[0007] With this combination of elements it has only proved possible to utilize energy released by chemical reactions or to control chemical reactions using electrical energy and all the prior art is concerned with these two processes. Cells have been proposed that make use of other elements for the purpose of conversion of nuclear fusion energy including types of porous electrodes used for “crowding of ions”. However the extra elements are exotic and expensive, none of the cells convert directly to electrical energy and none of the cells are in common use.
SUMMARY OF THE INVENTION
[0008] According to a first aspect of the invention there is provided a commutator comprising at least a first and a second plate arranged to move relative to one another, one of the plates comprising at least one input port arranged to allow a fluid to enter the commutator and one of the plates comprising at least one output port arranged to allow a fluid to exit the commutator, and at least one of the plates comprising at least one connector, which is capable of connecting the at least one input port to the at least one output port, wherein the plates are arranged such that as the plates move relative to one another the connector periodically connects the input port to the output port.
[0009] An advantage of such an arrangement is that it can periodically connect the input port to the output port while simultaneously allowing fluid to pass through the commutator. By arranging the connector in an appropriate manner it is possible to control the flow of fluid through the commutator in a desired manner.
[0010] Conveniently, the plates are arranged such that they rotate relative to one another. Alternatively, or additionally, the plates may translate relative to one another.
[0011] The input port and the output port may be provided in the first plate and the connector may be provided in the second plate.
[0012] Conveniently one of the plates, generally the first plate, is held substantially stationary. Such an arrangement is convenient because it provides a stationary plate to which the input and output ports can be coupled.
[0013] One of the plates, generally the second plate, may be arranged to rotate relative to the other.
[0014] In one embodiment the input port comprises a hole passing through the first plate. Such an arrangement provides a simple arrangement allowing fluid to enter the commutator.
[0015] The connector may comprise a groove in the surface of the second plate, which in the preferred embodiment comprises a portion of a ring.
[0016] The first and second plate may be substantially circular and are preferably arranged to be held concentrically adjacent one another.
[0017] Preferably, the fluid comprises a liquid electrolyte. Such an arrangement in convenient for passing an electric current therethrough.
[0018] Conveniently, the commutator is arranged to allow an electric current to be passed through the fluid passing therethrough.
[0019] Preferably, the commutator comprises a means arranged to produce a signal indicating the relative position of the first and second plates. In the preferred embodiment the means comprises one or more Hall effect sensors and an associated magnet.
[0020] The commutator may be referred to as a liquid commutator.
[0021] According to a second aspect of the invention there is provided an electrolytic system comprising
a container for an electrolyte arranged such that the electrolyte forms an electrical circuit; a commutator arranged to convert an AC electrical signal provided at a pair of input electrodes both immersed in the electrolyte to a DC signal at two points in the same electrolyte; a controller for controlling the movement of the commutator and the waveform of the applied AC voltage such that the movement of the commutator and the voltage have a predetermined relationship; and a set of working electrodes also provided within the electrolyte and arrange to pass a current therebetween.
[0026] The commutator may be the commutator of the first aspect of the invention. Alternatively, the commutator may be any of the other embodiments described herein.
[0027] Preferably, the system comprises a pump, which may be a pump, arranged to pump the electrolyte through the system. An advantage of the pump is that it helps to provide a smooth, controllable flow of electrolyte through the system.
[0028] The container will generally comprise a series of interconnected tubes. Conveniently, the ratio of the length of each tube to the cross sectional area is as large as possible. An advantage of a high ratio is that the electrical resistance provided by the electrolyte in the tube is consequently made as high as possible in order to minimise the initiation energy required to ignite reactions at the working electrodes.
[0029] The controller may be an electric/electronic circuit and in a preferred embodiment comprises at least one Hall effect sensor and an associated magnet means.
[0030] The controller may be arranged to generate a signal which is used to generate an AC voltage which is preferably synchronous with the movement of the commutator. The AC voltage may be applied to the input electrodes. An advantage of the commutator and controller running in this manner is that the effect of the applied AC voltage and the commutator is to produce a DC voltage at the output of the commutator.
[0031] The +ve end of this voltage is referred to, herein, as the “+ve virtual electrode” and the negative end as the “−ve virtual electrode”. This DC voltage is preferably applied across the working electrodes.
[0032] Preferably, any pump provided can be used to produce a steady flow of electrolyte from the +ve virtual electrode to the +ve working electrode and from the −ve virtual electrode to the −ve working electrode.
[0033] Flows from the working electrodes may be combined at the input of the pump.
[0034] The predetermined relationship between the AC voltage and the movement of the commutator may be to be in synchronism.
[0035] In one embodiment the commutator of the second aspect of the invention is that described in the first aspect of the invention.
[0036] The working electrodes may comprise a gas porous membrane. Such a membrane is advantageous because it allows gas generated at the electrode to escape therethrough and it therefore, may prevent the build up of gas at the working electrode.
[0037] Further, the working electrodes may be arranged such that ionic species within the electrolyte can be converted at the working electrodes such that the resulting faradaic current flowing in the electrolyte flows in the same direction as the flow of electrolyte within the container.
[0038] According to a third aspect of the invention there is provided a method of initiating a fusion reaction comprising:
providing a commutator allowing a fluid to pass therethrough; applying an AC voltage to the fluid on the first side of the commutator; providing a controller arranged to control the AC voltage such that it has a predetermined relationship to the movement of the commutator so as to generate a DC voltage in the fluid on a second side of the commutator; and applying the DC voltage to a pair of working electrodes such that an electrochemical reaction is initiated therebetween with said electrochemical reaction establishing a fusion reaction.
[0043] It is thought that an advantage of such a method is that it can be used to initiate and sustain a fusion reaction.
[0044] According to a fourth aspect of the invention there is provided a method of plating a component comprising:
providing a commutator allowing a fluid to pass therethrough; applying an AC voltage to the fluid on the first side of the commutator; providing a controller arranged to control the AC voltage such that it has a predetermined relationship to the movement of the commutator so as to generate a DC voltage on a second side of the commutator; and providing the component to be coated as at least one working electrode; and applying the DC voltage to a pair of such working electrodes such that an electrochemical reaction is initiated therebetween with said electrochemical reaction causing the component to be coated.
[0050] According to a fifth aspect of the invention there is provided a commutator comprising a fluid input port, a fluid output port and a connector arranged to periodically connect the input port and output port.
[0051] According to a sixth aspect of the invention there is provided an electrode comprising an electrode conductor, a gas porous membrane associated with a porous backing such that a space is created that is capable of allowing a fluid to flow therein between the electrode conductor and the gas porous membrane.
[0052] The gas porous membrane may be mounted upon the porous backing.
[0053] The fluid is generally a liquid and in particular may be a liquid electrolyte.
[0054] The electrode may be a referred to as a working electrode herein.
BRIEF DESCRIPTION OF DRAWINGS
[0055] There now follows by way of example only a detailed description of embodiments of the invention with reference to the accompanying drawings of which:
[0056] FIG. 1 shows a diagram representing the complete electrochemical circuit;
[0057] FIG. 2 shows an equivalent circuit in accordance with a preferred embodiment;
[0058] FIG. 3 shows a diagram representing a illustrative construction of working electrodes;
[0059] FIGS. 4 a to 4 e show diagrams representing the construction and operation of a liquid commutator in accordance with a preferred embodiment;
[0060] FIGS. 5 a and 5 b show voltage waveforms associated with a commutator; and
[0061] FIG. 6 shows a circuit suitable for allowing a commutator to provide the desired functionality.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0062] In one embodiment a system is provided which comprises a combined electrolytic/electric circuit being made up of the following elements and which are best seen in FIG. 1 :
an electrically conductive circuit 100 which comprises a plurality of interconnected tubes 102 which provide a container and contain a conductive element which in this embodiment is a liquid electrolyte. The tubes 102 allow the electrolyte to flow between the other elements of the conductive circuit 100 as described hereinafter. a commutator 104 providing a means of mechanically switching the electrolyte circuit in synchronism with an applied AC voltage, which will be described hereinafter. a pair of working electrodes 106 , 108 immersed in electrolyte in a vessel 110 on an output side 112 of the electrically conductive circuit 100 (to the left of the commutator in FIG. 1 ). a pair of input electrodes 114 , 116 immersed in the electrolyte to which the AC voltage is applied on an input side 118 of the electrically conductive circuit 100 (to the right of the commutator in FIG. 1 ).
[0067] A pump 120 (which in this example is a pump) arranged to pump the electrolyte through the commutator 104 towards the working electrodes 106 , 108 . In one embodiment, the pump includes of a pulsating metering pump and a condenser to provide a smooth controlled flow.
[0068] The ratio of the length of each section of tube 102 to the cross sectional area is as large as is conveniently possible to maximise the electrical resistance that the electrolyte presents to the electrode pairs (working electrode pair 106 , 108 and input electrode pair 114 , 116 ).
[0069] FIG. 3 , shows a suitable design for the working electrodes. Each electrode 106 , 108 comprises a conductor 300 , the material of which is able to withstand the conditions at the electrode surface and is unaffected by the electrolyte. A gas porous membrane 302 is provided adjacent the electrode conductor 300 such that a space 304 is provided between the two allowing electrolyte to flow therebetween. A stiff perforated backing 306 is provided on a back surface of the gas porous membrane (on the opposite side thereof to the electrode conductor 300 ) and provides mechanical support for the gas porous membrane 302 .
[0070] The gas porous membrane 302 is used to remove any gases produced by reactions occurring at the electrode surface of the electrode conductor 300 . The rate of gas production may require a near vacuum to be maintained on one side of the gas porous membrane 302 to enable gases to be pumped out. The stiff perforated backing 306 is used to hold the membrane close against the electrode conductor 300 , which is in made from metal in this embodiment.
[0071] Turning to FIGS. 4 a to 4 d which show a suitable design for the commutator 104 which consists of first 400 and a second plate 402 plate held against each other as shown in FIG. 4 a (which shows a side elevation of the arrangement) with one plate 402 rotating (the rotating plate) the other 400 fixed (the fixed plate). The fixed plate 400 has four holes, inlet A 404 and inlet B 406 allowing the electrolyte to flow into the commutator 104 and providing input and outlet A 408 and outlet B 410 allowing the electrolyte to flow out of the commutator 104 and providing an output. Each inlet 404 , 406 is connected, via the electrolyte, to an input electrode 114 , 116 . For example inlet A 404 to the input electrode 114 and inlet B 406 is connected to the input electrode 116 . The arrangement of the holes in the fixed plate 400 and the connections to the input electrodes 404 , 406 are explained hereinafter.
[0072] The rotating plate 402 has a first 412 and a second 414 groove in the surface that is held against the fixed plate 400 . These grooves do not pass entirely through the plate 402 , but are merely depressions therein and provide a connector. These grooves 412 , 414 are filled with electrolyte so that, when one of the grooves 412 , 414 simultaneously covers an inlet 404 , 406 and an outlet 408 , 410 , the inlet 404 , 406 and outlet 408 , 410 are connected via the electrolyte by a low electrical resistance. Otherwise, the inlets 404 , 406 and outlets 408 , 410 are connected via a high resistance film of electrolyte between the plates 400 , 402 . As can be seen from FIG. 4 c a suitable pattern for each of the first 412 and second 414 grooves comprises a roughly 160° portion of a ring co-centric with the centre of the plates 400 , 402 .
[0073] A means is provided to measure the rotational position of the rotating plate 402 and to generate a signal which is used to generate an AC voltage which is synchronous with the movement of the commutator 104 and which is applied to the input electrodes 114 , 116 . In one embodiment, the means that is provided to measure the rotational position of the rotating plate 402 comprises magnets 416 , 418 are placed on the rotating plate 402 and hall-effect devices 420 , 422 are placed on the fixed plate, at a 90° displacement to each other relative to the plates 400 , 402 , in order to detect the position of the rotating plate 402 relative to the fixed plate 400 . In other embodiments the means provided to measure the rotational position of the rotating plate 402 may be other than Hall effect detectors and may for example be any of the following (which is not intended to be an exhaustive list, but is provided for example only): an optical pickup, a stepper motor, a mechanical switch/contact, or the like.
[0074] To explain the operation of the commutator 104 the electrical connections through the commutator 104 are described as the rotating plate 402 moves in relation to the fixed plate 400 . However, the effect of the applied AC voltage and the commutator 104 is to produce a DC voltage at the output of the commutator 104 at virtual electrodes 121 , 122 (as shown in FIG. 1 ).
[0075] FIG. 4 d (which for convenience shows the position of elements with respect to one another even though some elements would be obscured from view) gives the position of the hall-effect detectors 420 , 422 on the fixed plate 400 , the magnets 416 , 418 on the rotating plate 402 and the grooves 412 , 414 at the point in the cycle when the voltage applied to input electrode 114 connected to inlet A 404 is changing from a negative voltage V− to an equal and opposite positive voltage V+ and the voltage applied to input electrode 116 connected to inlet B 406 is changing from V+ to V−.
[0076] An electronic circuit is connected between the hall-effect sensors 420 , 422 and the input electrodes 114 , 116 so that when a signal is output from detector B 422 the voltage applied to input electrode 116 connected to inlet A 404 is switched from V− to V+ and that applied to input electrode 116 connected to inlet B 406 from V+ to V−. For the following (π/2−Δ) radians of rotation of the rotating plate 402 the grooves 412 , 414 are in a position in which inlet A 404 is connected to outlet B 410 through the electrolyte and inlet B 406 is connected to outlet A 408 through the electrolyte. This means that the voltage in the electrolyte at outlet B 410 is approximately V+ and the voltage at outlet A 408 is approximately V− while inlet A 404 and outlet B 410 are connected together and inlet B 406 and outlet A 408 are connected.
[0077] FIG. 4 e (which, again, for convenience shows the position of elements with respect to one another even though some elements would be obscured from view) gives the relative positions when the voltage applied to input electrode 114 connected to inlet A 404 is changing from V+ to V− and the voltage applied to input electrode 116 connected to inlet B 406 is changing from V− to V+.
[0078] When a signal is output from detector A 420 the electronic circuit switches the voltage applied to input electrode 114 connected to inlet A 404 from V+ to V− and that applied to the input electrode 116 connected to inlet B 406 from V− to V+. For the following (π/2−Δ) radians of rotation of the rotating plate 402 the grooves 412 , 414 are in a position in which inlet A 404 is connected to outlet A 408 through the electrolyte and inlet B 406 is connected to outlet B 410 through the electrolyte. This means that the voltage in the electrolyte at outlet B 410 is approximately V+ and the voltage at outlet A 408 is approximately V− while inlet A 404 and outlet A 408 are connected together and inlet B 406 and outlet B 410 are connected. After the rotating plate 402 has rotated a further π/2 radians from this position the grooves 412 , 414 are in the same position as in FIG. 4D and the cycle repeats.
[0079] In one embodiment, the rotating plate 402 is driven by an AC induction motor rotating at just under 3000 rpm. This means that the voltage applied to the input electrodes 114 , 116 takes the form as given in FIG. 5 a (T=5.(1−(Δ/π))ms). It can be seen that the voltages at the inlets 404 , 406 are a square wave approximation to a Sine wave; i.e. a positive square wave of period T, followed by a negative square wave of period T, with a short period (relative to the period of the waves) between the positive and negative square waves.
[0080] The resulting voltages appearing in the electrolyte at outlet A 408 and outlet B 410 are given in FIG. 5 b . It can be seen that the voltage appearing at outlet B 410 comprises a series of positive square waves, and that the voltage appearing at outlet A 408 comprises a series of negative square waves.
[0081] A suitable circuit connected between the hall-effect detectors and the input electrodes is given in FIG. 6 and provides a controller arranged to maintain the applied AC voltage and the position of the plates in a predetermined manner. The output of the Hall effect detector A 420 is input to a first buffer 600 and the output of the Hall effect detector B 422 is input to a second buffer 602 . The output of the first buffer 600 is connected to the Set (S) input 604 of an SR flip flop 606 and the output of the second buffer 602 is connected to the reset (R) input 608 of the SR flip flop 606 . The output 610 of the flip flop 606 is buffered by a third buffer 612 which drives a switch 614 arranged to drive the input electrode A 114 . The NOT output 616 of the flip flop 606 is buffered by a fourth buffer 618 which drives a switch 620 arranged to drive the input electrode B 116 . The switches 614 , 620 may be any suitable electronic switches such as FET's MosFET's, or the like.
[0082] The waveforms of FIG. 5 a are AC waveforms; that is there is no DC content so there will be no electrochemical reactions occurring at the input electrodes. This is providing the frequency is high enough. With the rotating plate of the commutator rotating at 3000 rpm the frequency is ≈100 Hz which is high enough so that no reactions will occur. Elements may be added to the circuit, such as a transformer at the output 406 , 408 , so that it is impossible for any DC voltage to be applied to the input electrodes 114 , 116 . From the waveforms given in FIG. 5 b outlet B 410 is the +ve virtual electrode 121 (connected to the +ve working electrode 108 ) and outlet A 408 is the −ve virtual electrode 122 (connected to the −ve working electrode 106 ). Thus, the DC voltage produced by the commutator 104 is applied across the working electrodes 106 , 108 . It should be noted that this DC voltage is generated within the electrolyte without there being a corresponding electrochemical reaction.
[0083] The pump 120 is used to produce a steady flow of electrolyte from the +ve virtual electrode 121 to the +ve working electrode 108 and from the −ve virtual electrode 122 to the −ve working electrode 106 . These flows are combined at the input of the pump 120 . With an electrical load connected between the working electrodes 106 , 108 the effect of the applied AC voltage and the volume flow of the electrolyte is to produce a constant current source between the working electrodes 106 , 108 .
[0084] The magnitude of the current is only dependent on the volume flow rate and the ion concentration in the electrolyte. It is independent of the magnitude of the applied AC voltage and the magnitude of the electrical load. With this current flowing the limiting voltage between the working electrodes is very high.
[0085] A consideration of the thermodynamics of the electrode/electrolyte interface at the working electrodes 106 , 108 ; that is the conditions when no current is being generated in the external electrical load; indicates that very high partial pressures are present at the interfaces between the working electrodes 106 , 108 and the electrolyte. These pressures are such that it is expected that the solution at these interfaces will change state and will take the form of a plasma. A consideration of the possible electrochemical reactions at the working electrodes (as discussed hereinafter) indicates that energy may be derived from the system without there being a net change in the chemical state of the system. This means that the sources of the energy are nuclear reactions occurring at the working electrode/electrolyte interfaces. These reactions are not fission reactions involving heavy atomic weight elements, since energy is released without these elements being present, they are fusion reactions since only light or medium atomic weight elements are present that may combine in fusion reactions, releasing energy in the process. As well as energy conversion, an apparatus in accordance with a preferred embodiment may be used to coat the surfaces of the working electrodes with material under conditions of very high pressures and room temperature. A system in accordance with one embodiment may be considered as a system for igniting and controlling nuclear fusion reactions either for direct conversion to electrical energy or for the production of materials under conditions of very high pressure and normal temperature.
[0086] The separate commutator 104 and pump 120 constitute one possible embodiment. In another possible embodiment they are combined. The commutator consists of a set of 4 paddles attached to a vibrating beam. For part of the cycle of movement of the paddles the paddles are pressed against a surface providing a break in the conductive path for the electrolyte. If the paddles are positioned at the correct points on the beam the relative phases of movement of the paddles will be such that the cycle of conductive and non-conductive periods will be as for the commutator just described so that if an AC voltage is applied to a pair of input electrodes this AC voltage will be converted to DC at the outlets. The relative phases of movement of the paddles are such that the electrolyte is pumped from the inlets to the outlets.
[0000] The electrochemical reactions are described in terms of general redox reactions; that is, in terms of species O in solution being reduced to species R n− and species R in solution being oxidised to species O n+ . Reference is made to FIGS. 1 and 3 .
[0087] At the +ve working electrode 108 species O is entering the electrode 108 and being converted to R in the reaction O+n.e − →R n− and at the −ve working electrode 106 R is entering the electrode 106 and being converted to O in the reaction R-n.e − →O n+ . The conversion efficiency of the electrodes 106 , 108 may be defined as for a normal porous flow-through electrode as:
R = 1 - C ( out ) C ( in )
C(out) is the concentration of the active species leaving the electrode and C(in) the concentration entering the electrode.
The following argument deriving an estimation of the conversion efficiency and limiting current of the electrode assembly of FIG. 3 is based on that given in (ref. 1.).
Considering a random walk of an ion, an estimate of the average distance moved by an ion in time t is:
x =√{square root over (2· D·t )}
D is the diffusion constant of the ion.
This means that an estimate of the time taken for an ion to diffuse from the restrictor wall to the electrode is:
τ D = d 2 2 · D
d is the dimension given in the FIG. 3 .
The average transit time of an ion across the face of the electrode is
τ t = d · W · b f
f is the volume flow rate of the electrolyte and W and b are the dimensions given in FIG. 3 .
Following the same reasoning as in (Ref. 1) if τ t >t D the conversion efficiency will be high (R≅1). This is equivalent to the condition:
f < 2 · D · W · b d
Under these conditions the limiting current will be:
i Lim ≅C o ·F·n·f
C o is the concentration of the reacting species in the electrolyte being fed to the electrode, F is Faraday's constant and n is the number of charges on the ion.
With a DC voltage being applied to a pair of input electrodes instead of the present input electrode 114 , 116 /commutator 104 combination the current I L into the +ve input electrode 108 this will be producing charge Q I and the reduced species O n+ at the rate of:
I L = ⅆ Q I ⅆ t = n · F · ⅆ O + ⅆ t
The reaction at the electrode will be R-n.e − →O n+ and this charge will be entering the region of the electrolyte I.
Up to the limiting current the current I L flowing out of the +ve working electrode will be producing charge Q o and the oxidised species R n− at the rate of:
I L = - ⅆ Q I ⅆ t = - n · F · ⅆ R n - ⅆ t
O n+ and R n− in the last two equations are molar concentrations of the species.
The increases in the concentrations dR n− and dO n+ produce equal and opposite incremental currents in the region O of the electrolyte so there is no net charge entering this region.
Since, with an AC voltage applied to the input electrode/commutator combination as described herein non of the reduced species O n+ is being produced at the +ve input electrode a net charge Q=R×I L dt will be entering the region O and the current I S is a migration of ions due to a voltage gradient. This charge will be −ve since, as with a normal flow electrolysis electrode, the reaction O+n.e − →R n− is occurring, O is entering the electrode assembly and an increase in R n− is leaving the assembly. Because this charge is moving in the same direction as the volume flow of the electrolyte and the charge is negative it constitutes an electric current in the opposite direction of the volume flow as given in FIG. 3 . This current is in the same direction as the current in the external electrical load.
The value of this current is:
I = R · f V · ∫ I L ⅆ t
V is the volume of the region O.
With the AC voltage being applied and without the volume flow of the electrolyte the current Is will be made up of a flow of R n− being produced at the +ve working electrode and flowing towards the +ve virtual electrode and this current will be adding to the other migration currents caused by the voltage gradient.
From this consideration of the currents in the arrangement the equivalent circuit shown in FIG. 2 may be constructed:
Summing the currents at the +ve working electrode:
( V v - V O ) R I - V O R O + R · f · V O s · V · R L - V O R L = 0
s is the Laplace transform variable replacing the integration and V O and V V are the Laplace transforms of these variables. In the time domain if V V is a unit step function V O is:
V O = V v · R O · R L ( R O · R L + R I · R L + R I · R O ) · exp ( R · f · R O · R I · t V · ( R O · R L + R I · R L + R I · R O ) )
It should be noted that if R O in this equation for the output voltage of the equivalent circuit is infinite and the R I is zero the time taken for the output current to reach the limiting value is minimised. In other words if the resistance between the positive and negative electrode sets (i.e. the resistance between the +ve and −ve working electrode and between the +ve and −ve input electrode) is maximised compared to the resistances between the virtual and working electrodes within the sets the energy required to ignite the reactions at the working electrodes is minimised.
This indicates that the voltage at the working electrodes will rise exponentially until it is limited by a combination of the limiting current and the load resistance. The time taken to reach the limiting current will be:
T = V · ( R O · R L + R I · R L + R I · R O ) R · f · R O · R I · Log n ( I Lim · ( R O · R L + R I · R L + R I · R O ) V v · R O · ) `
Under steady state conditions the circuit looking into the working electrodes is a constant current source with a very high source voltage. The value of the current is not a function of the AC voltage at the input electrodes it is just a function of the volume flow rate of the electrolyte and the concentration of the active species. With no load current V O is stable at:
V O = V V · R O ( R O + R I )
This means that a reaction may be “ignited” at the working electrodes producing a constant current source which may be extinguished either by cutting off the external electrical load or by stopping the volume flow of the electrolyte.
As an example, if the electrolyte is an aqueous solution of sodium hydroxide the reaction at the +ve working electrode will be:
2H 2 O+2 e − →2OH − +H 2
the reaction at the −ve working electrode will be
4OH − −4 e − →2H 2 O+O 2
and the current in region O due to the volume flow will be due to excess OH − ions. Note that because these reactions produce gases and in the arrangement of the working electrodes shown in FIG. 3 it is the porous membrane that is used to extract the gases. This might be useful if the gases produced are a useful or desired product of the reactions. If the object is energy conversion then a more appropriate set of reactions may be the release and absorption of Li+ ions at graphite electrodes as used in the Li ion cell. In this case the porous membrane is not necessary since there are no gases given off and the electrode assembly may be realised by sandwiching an electrically isolating sheet between two graphite electrodes. The solution would be a simple salt of lithium—say LiS—in an organic solvent.
In a normal electrolytic cell the voltage appearing spontaneously, between a pair of electrodes under equilibrium conditions is the difference between the formal half cell potentials, E o , for each of the electrodes. “Equilibrium conditions” here, means that at every electrode/electrolyte interface in the cell there are no “net” reactions occurring of the type O+n.e − →R n− . This means that the reaction is in balance; that is, the reactions in the forward direction O+n.e − →R n− and reverse direction
O+n.e − ←R n− are occurring at an equal and opposite rate and the net reaction is zero. Under these conditions, the equation giving the formal half cell potential at each electrode is the Nernst equation:
E = E O + R · T n · F · Log n ( O R )
and the potential difference between any two electrodes is the difference in these potentials for the two electrodes. O and R in the equation are the relative concentrations of the species O and R taking part in the reaction. In a normal electrolytic cell the ratio of these concentrations is given by the relative numbers of moles of O and R taking part in the reaction and E O is the (Gibbs free energy of the reaction) X n X F so that the potential differences between any two electrodes is defined by the electrochemical reactions that may occur at the electrodes. With the cell described herein, this is not the case. Under equilibrium conditions the voltage appearing between the working electrodes is defined by the applied AC voltage and the relative resistances of the branches in the electrolytic circuit. Assuming that, under equilibrium conditions, only reactions of the type O+n.e − →R n− are occurring at the electrode/electrolyte interface E O in the equation cannot be more than a few volts since it relates to the Gibbs free energy of the reaction. This means that the difference has to be made up in the ratio of the concentrations (O/R). This is so because the difference cannot be made up from an increase in temperature T since this would mean a net power input into the system and under ideal conditions; that is, with very large electrical resistances through the electrolyte and negligible mechanical and electrical losses through the commutator; there is no energy input producing the voltage. Calculating the ratio (O/R) for a modest voltage difference of, say, 30V, gives a value for the ratio of the concentrations which is very large and which indicates that there is no R present in comparison to the amount of O present at the electrode/electrolyte interface. This may be explained if O is a positively charged species because there will be a certain charge distribution on the surfaces of the working electrodes due to the different potentials at the electrodes. Without the volume flow of the electrolyte, when a current flows in the external electrical load, O at the surface of the electrode is converted to R, the concentration of R increases, the concentration of O decreases and the voltage difference between the two working electrodes is determined partly by the Nernst equation, partly by the rates of the reactions at the electrodes and partly the supply of O to the working electrode determined only by the migration of O due to electric fields. The situation is different with a volume flow of electrolyte. The ratio of the concentrations of O and R in the Nernst equation appear in the equation because they are the same as the ratios of the partial pressures of O and R. Without the volume flow the decrease in the partial pressure of O when a current flows in the in external electrical load is determined only by migration of O to the electrode and the conversion of O to R at the electrode so that there are no very high partial pressures present. With the volume flow the supply of O to the working electrode is determined also by the flow. If the rate of supply of O due to the flow and the diffusion are such that for some finite partial pressure of R the ratio of the partial pressures of O and R is very high a nuclear fusion reaction may be ignited involving the charged species O in which case the reaction will be expected to gradually take over the other reactions occurring and the voltages in the Nernst equation and therefore the potential difference between the working electrodes will be proportional to the Gibbs free energy associated with this reaction. Since the power output from this reaction is controlled by the external electrical load RL the rate of the nuclear reaction in terms of the mass of reactants being used up per unit time can be vary small. The materials reacting can be determined by the choice of solute or solvent. For the case of the aqueous solution of sodium hydroxide the reactant at the +ve electrode is expected to be the combination of the sodium nuclei and that at the −ve electrode the combination of oxygen or hydrogen nuclei. With the rate of the nuclear reaction being very low and the choice available of reactants the radiation levels due to the reactions can be very low and the type of radiation can be relatively safe; that is, there need not necessarily be any high energy neutron radiation.
The elements of the electrolytic circuit of this embodiment are such that the apparatus may be built in a very large range of sizes.
While the preferred embodiments have been described in terms of a specific implementation, it should be apparent that the invention can be constructed using other elements for the liquid commutator, the working electrodes, the pump and the container for the electrolyte. The following reference, J. V. Kerkel & A. J. Bard. J. Electroanal. Chem. 54.47.(1974) is hereby incorporated by reference and the skilled person is directed to read this reference to fully understand the discussions herein.
In addition, in methods described herein and/or recited in the claims below, In addition, in methods that may be performed according to preferred embodiments and/or in the claims below, the operations have been described and/or recited in selected typographical sequences. However, the sequences have been selected and so ordered for typographical convenience and are not intended to imply any particular order for performing the operations, unless expressly set forth or those of skill in the art understand a particular ordering to be necessary. | A commutator comprising a first and a second plate arranged to move relative to one another is provided. One of the plates comprises at least one input port arranged to allow a fluid to enter the commutator and one of the plates comprises at least one output port arranged to allow a fluid to exit the commutator. At least one of the plates comprises at least one connector, which is capable of connecting at least one input port to at least one output port. The plates are arranged such that the plates move relative to one another and the connector periodically connects the input port to the output port. | 2 |
CROSS-REFERENCE TO RELATED APPLICATION
This application is a continuation-in-part of copending application Ser. No. 07/064,808, filed June 22, 1987, now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a process for the desulphurization of carbonaceous materials, and more particularly to a process for the desulphurization of petroleum coke having a sulphur content of over about 5% by weight, to provide a final coke product having a sulphur content of less than about 1% by weight. Desulphurization of the coke is accomplished by heating coke particles sequentially in a plurality of individual, spaced fluidized beds that are connected by inclined ducts, so that the petroleum coke particles pass from one fluidized bed to a succeeding bed through the inclined ducts.
2. Description of the Related Art
Heating of petroleum coke particles to desulphurize the particles can be effected in several ways, including the passing of an electric current through a fluidized bed of the particles. Because such particles can conduct electric current, the amount depending upon their electrical resistivity, such a heating technique is the most efficient way to directly heat the particles. Moreover, electrical heating can provide high particle temperatures of over 3000° C., and even as high as the temperature at which graphite sublimates (approximately 3700° C.).
The electrical resistivity of petroleum coke particles varies over a wide range, from thousands of ohm-cm. for undevolatilized petroleum coke having over about 5% sulphur content by weight, to about 1×10 -3 ohm-cm. for graphite that is obtained from petroleum coke. Devolatilized petroleum coke that contains over about 5% sulphur by weight has an electrical resistivity of approximately 10 ohm-cm. Low sulphur petroleum coke having a sulphur content of about 0.3% by weight, which can be obtained by desulphurizing petroleum coke having an initial sulphur content over 5% by weight, has an electrical resistivity of approximately 0.10 ohm-cm. Hence, the electrical resistivity of devolatilized but undesulphurized petroleum coke is on the order of about one hundred times higher than the electrical resistivity of desulphurized petroleum coke having a sulphur content of about 0.3% by weight. Further, desulphurized petroleum coke is partially graphitized.
If a high sulphur petroleum coke is to be continuously desulphurized by means of electrical heating in a single fluidized bed, as is suggested in U.S. Pat. No. 4,160,813, which issued July 10, 1979, to Markel et al., and if the coke particles are to act as an electrical resistance, it is necessary to have an electrical power system capable of providing a wide range of voltages and/or currents. The higher sulphur content particles entering the single fluidized bed have a higher electrical resistance, and when they are added to the partially desulphurized particles in the bed they sharply increase the electrical resistance of the totality of petroleum coke particles in the fluidized bed. Moreover, the electrical power delivered to heat the particles must be sufficient to permit the particles to reach a desulphurization temperature greater than about 1700° C. to obtain a sulphur content less than 0.5% by weight in the fluidized bed.
A disadvantage when using a single fluidized bed for the continuous desulphurization of petroleum coke is that the residence times of the particles can vary considerably, and the sulphur content of the particles at the output of the fluidized bed is therefore less uniform. Additionally, when using a single bed for the continuous treatment of high sulphur petroleum coke, the fluidized bed temperature must be high (greater than about 1800° C.), because the entering particles reach the temperature of the fluidized bed in seconds (in some cases the entering particles are preheated up to 1000° C.), and the resulting desulphurized petroleum coke is adversely affected in that the porosity of the particles increases and the mechanical strength of the particles decreases. Furthermore, even if several zones in a single vessel are separated by partitions, as is suggested in U.S. Pat. No. 2,983,673, which issued May 9, 1961, to Grove, and each separate zone is independently heated, because of heat transfer between the zones it is very difficult to maintain different temperatures in each zone.
SUMMARY OF THE INVENTION
The present invention overcomes the problems noted above by utilizing a plurality of separate fluidized beds that are interconnected in a series, wherein each fluidized bed except the last one, which is a cooling bed, contains particles that lie in a narrow, predetermined range of electrical resistance, and that have a corresponding narrow range of sulphur content, starting with the highest sulfur content particles in the first fluidized bed with particles having decreasing sulfur contents in the subsequent fluidized beds. The temperature of the particles in the first fluidized bed is the lowest of the particle temperatures in the heated beds, and the particle temperatures are maintained at successively higher levels in the other successive fluidized beds. Specifically, the temperature of the particles in the first fluidized bed is maintained at between about 1300° C. and about 1600° C., and the temperature of the particles in the last of the heated fluidized beds is maintained at a temperature greater than about 1900° C. The temperatures of the particles in the other fluidized beds are between that of the first fluidized bed and that of the last of the heated fluidized beds.
Each of the heated fluidized beds is divided by a vertical wall opposite the particulate material inlet, so that the particles of petroleum coke are deflected and must pass under the vertical wall before they pass into the electrical heating zone, which is located downstream of the vertical wall. The reason for avoiding the immediate entrance of the particles to the electrical heating zone is because the particles already within the fluidized bed have a lower sulphur content and a higher temperature than that of the entering particles, and the latter are preferably added on a gradual basis. The vertical wall also prevents the entering particles of petroleum coke from passing directly through a fluidized bed to the next fluidized bed.
In a zone between the particle inlet and the vertical wall in the first fluidized bed, the entering undevolatilized particles reach approximately 1000° C. and as a consequence they are substantially devolatilized.
The fluidization of the petroleum coke particles in each of the fluidized beds, including the cooling bed, is effected by introducing gas upwardly through the bottom of each bed. The gas can be nitrogen, argon, carbon monoxide, hydrogen, reformed natural gas, or mixtures thereof.
The coke particles in the several fluidized beds range in size from about -20 to about +80 mesh, and the fluidized beds are consecutively interconnected by inclined ducts, so that the particles of petroleum coke slide, due to the effects of gravity, from one fluidized bed to the next one.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a diagrammatic view showing one form of apparatus that can be used to carry out the process that is the subject of the present invention.
FIG. 2 is a transverse cross-sectional view through a heated fluidized bed, taken along the line 2--2 of FIG. 1.
FIG. 3 is a longitudinal cross-sectional view through a heated fluidized bed, taken along the line 3--3 of FIG. 2.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The process disclosed herein is described based upon the physical and chemical characteristics of petroleum coke that is obtained from the distillation of Mayan petroleum having a sulphur content of approximately 7% by weight, and it is based on the apparatus illustrated in the drawing figures. However, it will be appreciated by those skilled in the art that the description based upon Mayan petroleum is merely illustrative, and the process can be practiced using coke made from petroleum obtained from other sources.
Referring now to the drawing, and particularly to FIG. 1 thereof, particles of undevolatilized petroleum coke having a size of from about -20 to about +80 mesh and having a sulphur content of approximately 7% by weight flow by gravity from a loading hopper 1 through a flow control valve 2, that controls the feeding rate of the particles of petroleum coke, and through a duct 3 to provide a continuous flow of particles of petroleum coke to a first fluidized bed A. Beds A, B and C, which each have a capacity of about 15 kg of coke particles, are vertically spaced from each other so that the particles progress from the first bed at the highest elevation to each successive bed at a successively lower elevation to permit gravity flow of the particles from one bed to a succeeding bed. For example, the vertical separation between corresponding portions of successive beds can be about 50 cm.
Upon startup of the process, and before undevolatilized coke particles enter bed A from hopper 1, coke particles are added to each of the beds and are fluidized. The initial coke particles in each of the beds are of a particular particle size and sulphur level in order to permit the process to properly start. The particle sizes of the initial particles in each heated bed range from about -20 to about +80 mesh. In bed A the initial particles have a sulphur content of between about 3% and about 4% by weight and they are heated to a temperature of between about 1500° C. and about 1600° C.; in bed B the initial particles have a sulphur content of between about 1.2% and about 1.8% sulphur by weight and they are heated to a temperature of between about 1650° C. and about 1700° C.; and in bed C the initial particles have a sulphur content of between about 0.5% and about 0.9% by weight and they are heated to a temperature of between about 1950° C. and about 2200° C. The heating of the initial particles in each bed is accomplished by passing an electrical current between two electrodes that extend into the fluidized particles in each bed, to heat the particles in the respective heated beds to the initial temperatures specified above, and the heating of the particles is effected within the respective beds in substantially the same manner as is hereinafter described in the context of steady-state operation of the process.
In fluidized bed A the sulphur content of the petroleum coke particles is reduced from about 7% by weight to between about 3% to about 4% by weight by maintaining the temperature in fluidized bed A between about 1500° C. and about 1600° C. in a manner to be hereinafter described. The fluidization of the particles is effected by introducing gaseous nitrogen upwardly into the bottom of the bed A, through conduit 11 (also shown in FIG. 3).
In order to avoid the possibility of particles of undevolatilized petroleum coke passing directly through bed A and immediately into bed B, a vertical wall 4 is placed in bed A just downstream of inlet conduit 3 to deflect the petroleum coke particles downwardly toward the bottom of bed A. In zone 12 (see also FIGS. 2 and 3), between inlet conduit 3 and vertical wall 4, the undevolatilized particles are heated by thermal conduction to a temperature of approximately 1000° C. and they are thereby devolatilized. Vertical wall 4 prevents the petroleum coke particles from passing directly into the electrical heating zone 14, because to get to that zone the particles first have to pass under the lower edge of the vertical wall.
The heating of the particles in zone 14 is carried out by passing an electrical current through those particles of petroleum coke between two graphite electrodes 16, 18 (see FIGS. 2 and 3) that are spaced from each other by a predetermined distance (which can be approximately 7.5 cm for a 15 kg capacity bed) for the control of the electric current and therefore of the electrical power supplied. Preferably, the graphite electrodes have water cooled copper connectors (not shown). The residence time of the coke particles in fluidized bed A is between about 0.5 and 1 hour, and after that time the particles have a sulphur content of from about 3% to about 4% by weight.
Referring once again to FIG. 1, the particles of petroleum coke leave fluidized bed A through conduit 5 to fluidized bed B and they are deflected downwardly by the vertical wall 6 in bed B, as was the case with wall 4 in bed A, to avoid direct passage of the particles from bed B to bed C, and to cause the particles to more gradually enter the electric heating zone 20 in bed B. Thus, to get to the electric heating zone 20, the particles have to pass under vertical wall 6. The temperature in fluidized bed B is maintained between about 1650° C. and about 1700° C., and fluidization of the coke particles is effected by introducing gaseous nitrogen upwardly through conduit 22 that extends through the bottom of bed B. In fluidized bed B, the sulphur content of the coke particles is reduced to between about 1.2% and about 1.8% by weight. As was the case in bed A, heating of the coke particles in bed B is carried out by passing an electric current through the particles of petroleum coke between two graphite electrodes separated by a predetermined distance for the control of the electric current and therefore of the electric power supplied. The graphite electrodes preferably have water cooled copper connectors (not shown) and the use of nitrogen as the fluidizing gas avoids oxidation of the graphite electrodes. The residence time of the particles of petroleum coke in fluidized bed B is between about 0.5 and about 1 hour.
The particles of petroleum coke pass from bed B to bed C through conduit 7 and are diverted by vertical wall 8 in bed C to avoid their direct passage through bed C and into cooling bed D, and also to more gradually introduce the particles into electric heating zone 24, as was the case in beds A and B. In fluidized bed C the sulphur content of the particles is reduced to a level of between about 0.9% and about 0.5% by weight. The temperature in bed C is maintained between about 1950° C. and about 2200° C., and fluidization of the coke particles is effected by introducing gaseous nitrogen upwardly through conduit 26 into the bottom of bed C. The heating of the particles is carried out by passing an electric current through the fluidized particles of petroleum coke in heating zone 24 between two graphite electrodes that are separated by a predetermined distance for the control of the electric current and therefore of the electric power supplied. The graphite electrodes have water cooled copper connectors (not shown), and the use of nitrogen as the fluidizing gas avoids oxidation of the graphite electrodes. The residence time of the particles of petroleum coke in fluidized bed C is between about 0.5 and about 1 hour, and the sulphur content of the particles in bed C is reduced to between about 0.9% to about 0.5% by weight.
The particles pass from bed C through conduit 9 to fluidized bed D, which is not heated and which serves as a cooling bed for fluidizing and cooling the particles with nitrogen gas that is introduced through conduit 28 into the bottom of bed D to provide a particle cooling zone 30. The residence time of the particles of petroleum coke in fluidized bed D is between about 0.25 and about 0.5 hour.
After cooling, the particles of petroleum coke pass through conduit 10 into a hopper (not shown) for storage. The total time for the particles to travel from conduit 3 at the entrance to bed A to conduit 10 at the outlet of bed D is between about 2.5 hours to about 3.5 hours.
Below are the results of tests in the form of two examples of continuous desulphurization of particles of undevolitilized petroleum coke wherein the particle size ranges from about -20 to about +80 mesh, using the process steps and the apparatus as described above. In each example the particles of undevolatilized petroleum coke entering fluidized bed A have an initial sulphur content of about 7% by weight.
EXAMPLE 1
The particles of undevolatilized petroleum coke flowed from a hopper to first heated fluidized bed A at a feed rate of 20 kg/hour and were subjected to the temperature and flow conditions identified in the foregoing discussion. After the coke particles passed through each of heated fluidized beds A, B, and C the output from fluidized bed C was sampled at half-hour time intervals beginning immediately after steady-state conditions had been achieved and the desired temperatures were reached in the respective beds, and the percentage of sulphur by weight in the sampled particles was determined. The results of the sulphur determinations are presented below.
Samples at the outlet of fluidized bed C.
______________________________________Time % Sulfur, by weight______________________________________ 0 hour 0.890.5 hour 0.741.0 hours 0.731.5 hours 0.682.0 hours 0.702.5 hours 0.68______________________________________
At the conclusion of the test, after 2.5 hours had elapsed, the temperature (measured with an optical pyrometer) and the sulphur content of the coke particles in each of the heated fluidized beds were as follows:
______________________________________ Temperature, °C. % Sulphur, by weight______________________________________Bed A 1500 3.93Bed B 1650 1.63Bed C 1950 0.68______________________________________
EXAMPLE 2
The same apparatus and process as in Example 1 was repeated except that the feed rate of the particles of undevolatilized petroleum coke to bed A was 10 kg/hour.
Samples at the outlet of bed C.
______________________________________Time % Sulphur, by weight______________________________________0.0 hour 0.640.5 hour 0.651.0 hour 0.511.5 hours 0.532.0 hours 0.492.5 hours 0.54______________________________________
At the conclusion of the test, after 2.5 hours had elapsed, the temperature (measured with an optical pyrometer) and the sulphur content of the coke particles in each of the heated fluidized beds were as follows:
______________________________________ Temperature, °C. % Sulphur, by weight______________________________________Bed A 1550 3.65Bed B 1700 1.47Bed C 1980 0.54______________________________________
X-ray diffractograms taken of particles of undevolatilized petroleum coke, and of particles of petroleum coke having a sulphur content of 3.65% by weight, of 1.63% by weight, of 0.89% by weight, of 0.51% by weight, and graphite grade electrode, showed that with the decreasing sulphur content, the degree of graphitization of the particles of petroleum coke progressively increased.
Although particular embodiments of the present invention have been illustrated and described, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit of the present invention. It is therefore intended to encompass within the appended claims all such changes and modifications that fall within the scope of the present invention. | A process for the desulphurization of residuals of petroleum distillation in the form of coke particles having an initial sulphur content greater than about 5% by weight. Desulphurization is effected by means of a continuous electrothermal process based on a plurality of sequentially connected fluidized beds into which the coke particles are successively introduced. The necessary heat generation to desulphurize the coke particles is obtained by using the coke particles as an electrical resistance in each fluidized bed by providing a pair of electrodes that extend into the fluidized coke particles and passing an electrical current through the electrodes and through the fluidized coke particles. A last fluidized bed without electrodes is provided for cooling the desulphurized coke particles after the sulphur level has been reduced to less than about 1% by weight. | 2 |
CLAIM FOR PRIORITY
[0001] A claim for priority is made in this application for the provisional application No. 60/352,358 filed on Dec. 14, 2001.
FIELD OF THE INVENTION
[0002] The present invention relates generally to the fields of visual signals and visual safety devices. More particularly, the present invention relates to a visual signaling system for enabling a driver of a vehicle to precisely and safely position the vehicle in a parking space, garage or relative to some other objects.
BACKGROUND OF THE INVENTION
[0003] Parking a vehicle in a confined space can be difficult. When the vehicle is moved into the space, traveling in either forward or backward direction, the potential exists for the driver to incorrectly estimate the confines of the space in relation to the physical dimensions of the vehicle. The consequence of this is the possibility of contact between the vehicle and other property (wall, garage door, another vehicle, etc.) within close vicinity to the vehicle. This contact may result in damage to the vehicle and/or the other property.
[0004] The driver's incorrect estimation is a concern even if the driver is exercising due care. There are several reasons for this. First, it can be difficult to judge the appropriate target position for the vehicle. Factors that are weighed in this judgment include the appropriate amount of space needed for the operation of certain features of the vehicle (car doors, car hoods, car trunks, etc.), the appropriate amount of space needed for the operation of features of property in the vicinity of the vehicle (garage doors, structural doors, etc.), and access to other property (other vehicles, storage, etc.). Second, it is difficult to judge the size of a vehicle while it is being operated. Third, the confined space in which to park the vehicle may be so physically confining that the margin of error for the driver's judgment can be extremely small.
[0005] Property damage due to vehicle parking mistakes is also a risk management problem from the point of view of insurance companies. If a way can be found to minimize such accidents, then insurance claims would decrease. A competitive advantage could be realized by an insurance company if they can manage risk for their own policy holders so as to minimize such accidents.
[0006] One solution to the problem is to employ the assistance of a separate person not positioned within the vehicle to aid the driver in navigating the vehicle into the appropriate position within the confined space. However, in most instances, this is not a practical solution. Other solutions use range finding devices to convey to the driver the amount of distance between the vehicle and other objects. This solution is cost prohibitive and is not pragmatic. The solution to this problem must be one that is exercisable by the driver alone without any assistance from another person and must be affordable to the average driver.
[0007] There have been previous attempts to solve this problem under the above criteria which have employed the use of various devices in order to allow a single driver to appropriately position a vehicle. One example, U.S. Pat. No. 6,199,287 to Rankila, Mar. 13, 2001, discloses a device for positioning a vehicle in a predetermined location. This device is comprised of two spatially separated but conjoined planar surfaces, the first of which is mounted on a wall and the second is extended toward the driver. While this device will assist the driver in positioning the vehicle when the second planar surface is aligned with and obscures a portion of the first planar surface, it has several drawbacks. In its rigid form, the device actually provides another obstruction that could cause damage to a vehicle because the distance required to separate the first and second surfaces must be of more than negligible in order for this device to operate properly (too short of a distance would provide too great of a tolerance in the desired parking position). In its retractable embodiment, the device would require a driver to exit the vehicle in order to reset the device into its operable position before attempting to position the vehicle. This is extremely inconvenient to the driver. Finally this device requires the driver's attention to be focused on the device and not on the pertinent surroundings in the parking space. This lack of attention on the pertinent surroundings could cause more extensive damage than what the device is attempting to correct.
[0008] Another example is U.S. Pat. No. 4,813,758 to Sanders, Mar. 21, 1989, which discloses a device for positioning a car in a garage. This device comprises lateral and longitudinal positioning members. Lateral alignment is achieved when the lateral positioning members are aligned. Longitudinal alignment is achieved when the headlights of the vehicle being operated are reflected, through the use of a mirror, into the driver's eyes. This device also has several drawbacks. First, it can only be used when parking in a forward moving direction since it must be mounted on the wall opposite the entry to the parking space. The device could not be mounted on the garage door to allow for backing into the parking space, by virtue of the obvious fact that the garage door must, necessarily, be in the open position to allow for access to the parking space. Secondly, it requires the driver's strict attention to the device to perceive the lateral alignment of the lateral positioning members, thus distracting the driver from the other pertinent surroundings. Thirdly, the operation of the device requires the device to reflect the vehicle's headlights directly into the driver's eyes, thus creating a hazardous situation. Finally, relying on the driver's headlights for alignment may be difficult during the day if the parking space is exposed to light. Also, using headlights during the day increases the opportunity for drivers to leave their headlights on after exiting the vehicle, thus depleting the battery of the vehicle.
[0009] Yet another example of a car positioning device is U.S. Pat. No. 5,127,357 to Viscovich, Jul. 7, 1992, which utilizes a mirror mounted on a surface in a garage to reflect light to the side rear-view mirror on a vehicle. The invention operates by reflecting the illuminated brake lights into the side rear-view mirror when the vehicle is properly positioned. The shortcomings of this invention involve requiring the driver's attention to be focused on the rear-view mirror, thus distracting the driver from other pertinent surroundings. In addition, the tolerance of proper positioning is inherently large as the mirrors will reflect all incident light and the driver must judge the magnitude or intensity of the reflected light in order to properly position a vehicle. This could lead to imprecise positioning of the vehicle.
[0010] All of the previous attempts do not adequately solve the vehicle positioning problem. Thus, what is needed is a device and method for using that device that 1) helps drivers park their cars more accurately, 2) does not require strict attention to the device, 3) functions properly while a vehicle is traveling in both forward and backward directions, and 4) provides for moderately precise positioning of a vehicle without creating further hazards in the parking space.
OBJECTS OF THE INVENTION
[0011] It is an object of the present invention to provide a way to signal a driver when to stop a vehicle in a parking space without requiring the help of an assistant or expensive technology.
[0012] It is yet another object of the present invention to provide a visual signal device that signals a driver when to stop a vehicle in a parking space without requiring the focused attention of the driver to be on the signal device.
[0013] It is yet another object of the present invention to provide a visual signal device that signals a driver when to stop a vehicle in a parking space that can be utilized while traveling in either forward or backward directions.
[0014] It is yet another object of the present invention to provide a visual signal device combined with a medium for visual advertising.
[0015] It is still yet another object of the present invention to provide a visual signal device that works in poorly-lighted conditions as well as well-lighted conditions.
[0016] It is still yet another object of the present invention to provide an adjustable visual signal device that signals a driver when to stop a vehicle in a parking place when that vehicle is properly positioned.
[0017] It is a further object of the present invention to provide a visual signal device that will not damage a vehicle if that vehicle collides with the device.
[0018] It is a further object of the present invention to provide a system that helps drivers park their vehicles more accurately, which can be mass distributed at an economically reasonable cost.
[0019] The foregoing and other objects will be apparent from the drawings and the description set forth herein.
SUMMARY OF THE INVENTION
[0020] This invention relates to a visual signal device that aids a driver of a vehicle to position that vehicle in a precise location. The signal device allows the driver to use his peripheral vision to properly position the vehicle. The signal device is positioned on a wall or other structure adjacent a parking space, where such wall or other structure has a surface that is at least approximately parallel to the direction of travel of the vehicle. In one embodiment, as a vehicle first travels into the parking space, the proximal side of the device obstructs the distal side of the device and, therefore, only the proximal side is within the driver's field of view. Upon attaining the optimal position within the parking space, the distal side of the device comes within the driver's field of vision, engaging the driver's peripheral vision, and signaling the driver to stop the vehicle. The proximal and distal sides of the device are of colors and/or materials such that the contrast between the proximal and distal sides is readily apparent. In a different embodiment, as the vehicle first travels into the parking space, both the proximal and distal sides are within the driver's field of view. Upon attaining the optimal position within the parking space, the proximal side of the device disappears from the driver's field of view signaling the driver to stop the vehicle. The proximal and distal sides of the device are of such colors and/or materials that again, the contrast between the proximal and distal sides is readily apparent. These proximal and distal sides can be formed by folding the device along designated lines or manipulating the device using multiple layers of signal surfaces
[0021] The invention, when placed in operational configuration, is entirely passive as there are no moving parts. The stop signal is effective simply by the movement of the car relative to the stationary device such that either the distal side suddenly is within the field of view of the driver or the proximal side disappears from the field of view of the driver when the vehicle attains an optimal position within the parking space.
[0022] The invention is uniquely advantageous over the prior art in that it is converted from a shipping configuration to the operational configuration with relative ease. The shipping configuration is such that it can be mass mailed and is no larger nor heavier than an ordinary mailer of conventional size. The invention converts from the shipping configuration to the operational configuration by manipulation of the various surfaces. Some embodiments require at least one folded surface to be releasably attached to the mounting surface surfaces in order to function appropriately while in operational formation. The invention is further advantageous in that the material of the device is of such a quality so that it remains durable when attached to wall in the operational configuration but does not provide any additional obstacles within the parking space nor is capable of causing damage to the vehicle if a driver improperly negotiates the parking space.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] [0023]FIG. 1 illustrates a top plan view of the operational formation of the signal device according to various embodiments of the present invention with a vehicle traveling in a forward direction.
[0024] [0024]FIG. 2 illustrates a top view of the signal device according to a first embodiment of the present invention.
[0025] [0025]FIG. 3 illustrates a top view of the signal device according to a second embodiment of the present invention.
[0026] [0026]FIG. 4 illustrates the use of the device when in operational formation as attached to a opposing surface.
[0027] [0027]FIG. 5 illustrates a top plan view of the operation of a signal device according to various embodiments of the present invention with a vehicle traveling in a backward direction.
[0028] [0028]FIGS. 6A illustrates a lay-out view of a first side of the invention in the unfolded shipping formation.
[0029] [0029]FIG. 6B illustrates a lay-out view of a second side of the invention in the unfolded shipping formation.
[0030] [0030]FIG. 7 illustrates a close up view of the locking mechanism used to convert the invention from shipping formation to operational formation.
[0031] [0031]FIG. 8 illustrates a cross sectional view of the signal device according to a third embodiment of the present invention.
[0032] [0032]FIG. 9 illustrates a close up view of the device of FIG. 8 in the unfolded shipping formation.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0033] [0033]FIG. 1 illustrates one embodiment of the signal device 11 in its operational formation. The signal device 11 comprises a proximal surface 13 , a distal surface 15 , a mounting surface 17 , and a graphic display surface 31 . The mounting surface 17 of the signal device, which is shown in more detail with reference to FIG. 2, is engaged with an opposing surface 18 through the use of any adhesive (not shown) which is known in the art. The signal device 11 is mounted at a height such that it can be viewed by a driver 19 , having a seated position within a vehicle 21 . This height is such that any information contained on the graphic display surface 31 will be prominently displayed within the confined parking space. The use of graphic display surface 31 is further discussed with reference to FIG. 2. Further the signal device 11 is longitudinally mounted such that when the vehicle 21 is positioned appropriately within the confined parking space, the driver 19 is able to recognize a contrast in color and/or material between proximal surface 13 and distal surface 15 .
[0034] With further reference to FIG. 1, driver 19 of vehicle 21 traverses a confined parking space in a forward motion. In first position 23 , the driver 19 only has the ability to see the proximal surface 13 and not the distal surface 15 of signal device 11 . The driver 19 then navigates the vehicle 21 to a second position 25 . Second position 25 represents the precise position in which color and/or material contrast between the proximal surface 13 and the distal surface 15 of the signal device 11 first comes into said driver's field of view, represented by peripheral view line 27 . Upon reaching position 25 , the driver 19 will stop the vehicle 21 , which will be properly positioned in the confined parking space.
[0035] In an alternate embodiment, with further reference to FIG. 1, driver 19 will have the ability to see both proximal surface 13 and distal surface 15 at first position 23 . The driver 19 then navigates the vehicle 21 to second position 25 . Second position 25 , in this embodiment, represents the precise position in which proximal surface 13 is no longer within the field of view of driver 19 . In both embodiments, proximal surface 13 is substantially perpendicular to mounting surface 17 . The two embodiments above differ in the value of the interior angles formed by proximal surface 13 , distal surface 15 , and mounting surface 17 . These angles are discussed in detail with reference to FIG. 2.
[0036] [0036]FIG. 2 illustrates a top view of the signal device in operational formation. Distal surface 15 is obscured from vision by proximal surface 13 of the signal device until a driver (not shown) attains the peripheral view line 27 . FIG. 2 further illustrates mounting surface 17 which can be affixed to a wall or other structure (not shown). This affixation is accomplished thought the use of any adhesive (not shown) which is known in the art. FIG. 2 further illustrates the use of a display surface 31 , which is adjacent distal surface 15 . This display surface is useful as advertisement, solicitation or promotional space. This use of space for advertising aids in maintaining a prominent profile for the company that bears the cost of manufacturing and/or distributing the signal device. Additionally, or as an alternative, the display space is useful to convey any message, for example a public service message or a safety encouragement.
[0037] [0037]FIG. 2 further illustrates the angles formed by surfaces 13 and 15 when in operational formation according to this embodiment. Signal device 11 comprises first, second, and third angles, 33 , 35 , and 37 . The first angle 33 formed by the proximal surface 13 and the mounting surface and is substantially 90°. The second angle 35 formed between proximal surface 13 and distal surface 15 can vary from between 0° and 90°. Finally the third angle 37 formed between the distal surface 15 and the mounting surface 17 can vary from between 0° and 90°. As is shown, FIG. 2, angles 35 and 37 must cumulatively equal approximately 90°. In order for proximal surface 13 to obscure distal surface 15 from being within the field of view of the driver 19 (not shown), according to one embodiment, angle 35 must be relatively small as compared to angle 37 . In this embodiment, the device will function by signaling the driver 19 (not shown) to stop vehicle 21 (not shown) when distal surface first comes into the field of view of driver 19 (not shown). As angle 35 becomes larger, and angle 37 becomes correspondingly smaller, it is more likely that distal surface 15 will be within the field of view of driver 19 (not shown) upon first entering a parking space, thus relating to a different embodiment. In this different embodiment, the device will function by signaling the driver 19 (not shown) to stop the vehicle 21 (not shown) when proximal surface 13 first disappears from the field of view of driver 19 (not shown).
[0038] [0038]FIG. 3 is an illustration of an alternate embodiment of the present invention. As shown in FIG. 3, third angle 37 is substantially 90° and angles 33 and 35 vary from between 0° and 90° and cumulatively equal approximately 90°. In this embodiment, the device will function by signaling the driver 19 (not shown) to stop vehicle 21 (not shown) when distal surface first comes into the field of view of driver 19 (not shown).
[0039] [0039]FIG. 4 is a cut away view of a driver 19 in a vehicle 21 after the vehicle 21 is navigated to second position 25 (not shown) where the distal portion 15 of the signal device 11 is just visible to driver 19 , thus signaling to driver 19 that vehicle 21 has attained an appropriate stopping position.
[0040] [0040]FIG. 5 illustrates the invention of FIG. 1 with the modification that the driver and vehicle are traversing the confined parking space in a backward motion from a first position 23 to a second position 25 . The height of the device will remain constant but the device will be longitudinally mounted in a different location in order to assure proper positioning of the vehicle within the confined parking space. Signal device 11 functions in precisely the same manner according to one embodiment described above in that at the instant the distal surface 15 of the signal device 11 comes within the driver's peripheral view line 27 , the vehicle will be properly positioned within the confined parking space.
[0041] [0041]FIGS. 6A and 6B illustrate the shipping formation of the signal device 11 in its completely unfolded shipping (or storage) configuration. The shipping formation of the signal device includes first and second surfaces, 43 and 45 respectively. First surface 43 includes proximal surface 13 , distal surface 15 as disclosed with reference to FIG. 1, and display surface 31 as disclosed with reference to FIG. 2. First side 43 also includes a tab 47 . Tab 47 is of a shape such that it will engage and become detachably connected to slot 49 when the signal device 11 is in its operational formation. First side 43 additionally includes surfaces 51 , 55 , and 57 . These surfaces can be used for the display of various information, including but not limited the return address for a business reply card, directions of on the use of the signal device, or any promotional advertising and/or logo.
[0042] [0042]FIG. 6A further illustrates that first surface 43 of signal device 11 is perforated along three perforation lines 59 , 61 , and 63 . These perforation lines, as is known in the art, are used to easily separate two previously conjoined portions of the signal device 11 . Therefore, surfaces 51 , 55 and 57 can be separated from the remainder of the signal device before the device is manipulated into its operational formation. FIG. 6A further illustrates fold lines 67 , 69 , and 71 by which a recipient of the signal device in the shipping formation will fold the device. In an alternate embodiment, fold line 71 can be eliminated such that, when in its operational formation, surfaces 15 and 31 will be substantially planar. In this embodiment, surfaces 15 and 31 may be of substantially the same color and/or material. First side 43 can be further configured to contain slots 73 and 75 . Slots 73 and 75 are positioned on surface 31 such that a normally sized business card can fit between the slots. Finally, first side 43 includes mounting surface 17 as disclosed with reference to FIGS. 1 and 2.
[0043] As illustrated in FIG. 6B, second side 45 is the opposite side of first side 43 and therefore maintains the many of the same attributes as first side 43 . Tab 47 , slot 49 , perforation lines 59 , 61 , and 63 , fold lines 67 , 69 , and 71 , and slots 73 and 75 are in the same position as disclosed with reference to first side 43 of the signal device 11 and are therefore not shown. Second side 45 further includes surfaces 81 , 85 , 87 . These surfaces can be used for, but are not limited to, the display of advertising, promotional logos, survey questionnaires, and addresses of recipients of the signal device 11 . Because surfaces 81 , 85 and 87 are simply the reverse side of surfaces 51 , 55 and 57 , they can be separated from the remainder of the device as discussed above with reference to FIG. 6A. If the manufacturer of the device should wish to place a survey questionnaire in the signal device, the questionnaire must be directly opposite the business reply address as disclosed with reference to side 43 in FIG. 6A.
[0044] [0044]FIG. 7 is a detailed view of the portion of the signal device 11 . More particularly, FIG. 7 shows an alternate embodiment of the attaching mechanism of the signal device 11 . Tab 91 is used to engage slot 49 of the signal device 11 instead of tab 47 which is disclosed with reference to FIGS. 6A and 6B. All other features of the invention in this embodiment are identical to those disclosed with reference to FIGS. 6A and 6B.
[0045] [0045]FIG. 8 illustrates still another embodiment of the present invention. With reference to FIG. 8, proximal surface 13 and distal surface 15 are disposed such that they are substantially co-planar with each other and substantially perpendicular with mounting surface 17 . In addition, FIG. 8 illustrates the use of a third surface 93 . Third surface 93 is adjacent distal surface 15 , substantially co-planar with mounting surface 17 , and, thus substantially perpendicular with surfaces 13 and 15 . Third surface 93 can be of the same color of distal surface 15 or can be a third color. In operation, this alternate embodiment will function in such a way that as a driver 19 (not shown) of a vehicle 21 (not shown) enters a parking space, only proximal surface 13 will be visible. Upon attaining an the desired second position 25 , distal surface 15 and third surface 93 will some within the driver's field of view thus signaling to driver 19 (not shown) to stop the vehicle 21 (not shown).
[0046] [0046]FIG. 9 illustrates the embodiment as discussed with reference to FIG. 8 above in the unfolded or storage configuration. Surface 93 is adjacent distal surface 15 and graphic display surface 31 . Line 95 distinguishes between surface 93 and graphic display surface 31 . All other features of the invention in this embodiment are identical to those disclosed with reference to FIGS. 6A and 6B.
[0047] Whereas the drawings and accompanying description have shown and described the preferred embodiments, it should be apparent to those skilled in the art that various changes may be made in the form of the invention without affecting the scope thereof. | The Signal Device for Positioning a Vehicle, according to the present invention relates to utilizing the peripheral vision of a driver of a vehicle in assessing the proper position of a vehicle relative to a confined parking space. The device is comprised of at least two surfaces, the first obscuring the second until the vehicle has attained the desired position within the parking space. Upon attaining this position, the second surface will come within the operator's field of vision thus notifying the operator to stop the vehicle. Alternately, the operator will stop the vehicle when the second surface obscures the first surface. Additionally, this invention includes a method for parking a vehicle in a confined parking space. Finally, this invention describes a method of distributing advertising and/or solicitation through mass mailing techniques, such advertising accompanying the signal device. | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to European application 12194772.5 filed Nov. 29, 2012, the contents of which are hereby incorporated in its entirety.
TECHNICAL FIELD
[0002] The invention relates to temperature measurements in the pressurized flow path of a gas turbine and the use of such a measurement in the control of a gas turbine as well as a gas turbine comprising such a measurement.
BACKGROUND
[0003] Different temperature measurements for Gas turbines are known. Typically these are based on thermo couples or resistance thermometers. However, due to the harsh environment in a gas turbine they need to be capsuled for use in the pressurized flow path and are therefore relatively slow to detect transient changes in temperatures. Further, the hot gas temperatures in gas turbines are often too high for the use of direct measurements.
[0004] Optical pyrometers have also been used as a way to take spot readings (primarily in combustion zones). Optical pyrometers have not been widely used as continuous measurement devices in gas turbines. They do not work well below about 900° C. and would not be useful for monitoring during start-up and at low load. Further, optical access is difficult to the pressurized part of the gas turbine flow path.
[0005] The concept of measuring temperature based on the propagation speed of acoustic waves has been known for a long time. However, engine noise has so far prevented the use such a concept.
SUMMARY
[0006] One aspect of the present disclosure is to provide a method for determining a temperature in a pressurized flow path of a gas turbine using the concept of measuring temperature based on the propagation speed of acoustic waves.
[0007] The speed of sound through a gas depends on its specific heat ratio, the specific gas constant, and absolute temperature as follows:
[0000] c =(□* R spec *T ) 0.5
[0000] where:
c is the speed of sound [m/s], □ is the specific heat ratio [−], T is the absolute temperature [K], R spec =R/M
with:
the universal gas constant R, [8.314 J K −1 mol −1 ], and the molecular mass M [g/mole] of the gas.
[0014] According to a first embodiment a temperature in a pressurized flow path of a gas turbine downstream of a compressor and upstream of a turbine comprises the following steps:
[0015] sending an acoustic signal from an acoustic signal emitting transducer arranged to send an acoustic signal across at least a section of a cross section of the pressurized flow path,
[0016] detecting the acoustic signal with a receiving transducer arranged to receive the acoustic signal after the acoustic signal crossed the section,
[0017] measuring the time needed by the acoustic signal to travel from the acoustic signal emitting transducer to the receiving transducer,
[0018] calculating the speed of the acoustic signal, i.e. the speed of sound in the section passed by the acoustic signal, based on the measured traveling time and distance between acoustic signal emitting transducer and the receiving transducer,
[0019] providing a heat capacity ratio and a specific gas constant of the gas flowing in the pressurized flow path,
[0020] and calculating the temperature of the gas in the section of the pressurized flow path as a function of the speed of sound, the heat capacity ratio and a specific gas constant of the gas flowing in the pressurized flow path.
[0021] In this context “arranged to send an acoustic signal across at least a section of a cross section of the pressurized flow path” for example means that the acoustic signal emitting transducer is installed such that the acoustic signal emitting end of the transducer is directed in the direction of the section which the acoustic signal shall pass. Preferably it is installed flush with the side wall of the flow path to avoid turbulences, which can interfere with the acoustic signal. “Arranged to receive the acoustic” signal typically means that the receiving transducer is installed in line of sight of the emitting transducer or in line of sight of an acoustic wave directly reflected from a wall of the flow path.
[0022] According to one embodiment the combustion pulsation pressure is measured over frequency, and the maximum pulsation pressure is determined. To facilitate detection of the acoustic signal the frequency of the acoustic signal emitting transducer is tuned to a frequency, with a combustion pulsation pressure, which is less than 20% of the maximum pulsation pressure. Preferably, the frequency of the acoustic signal emitting transducer is tuned to a frequency, with a pulsation pressure, which is less than 10% of the maximum pulsation pressure.
[0023] For better accuracy the signal received by the receiving transducer can be filtered for combustor pulsation and/or noise produced by the gas turbine. The combustor pulsations and/or noise can be recorded with the transducers used for determining the acoustic signal. The pulsation and/or noise produced by the gas turbine can also be measured at other locations, which can be at a distance from the acoustic receiving transducer and the measured signal. For better separation of the pulsation signal from the emitted acoustic signal the signal can be transferred to the location of the receiving transducer. For this transfer the distance and traveling time between the remote location and receiving transducer has to be taken into account.
[0024] According to one embodiment the acoustic signal send by the acoustic signal emitting transducer can be pulsed, i.e. it is only send intermittently to create a short acoustic peak. This facilitates distinction of the acoustic signal over the engine noise and pulsations. Preferably a short peak with a steep onset and abrupt end is used. Ideally the emitting transducer emits at maximum amplitude from the first acoustic wave it emits. The traveling time can be determined by the time it takes from emitting the first wave to the time an increase in the sound level at the emitted frequency is recognized by the receiving transducer. In this case a single acoustic wave can be sufficient. The pulse interval, i.e. the time between sending pulsed acoustic signals, can be in the order of several (at least two) times a wave length divided by the speed of sound to the order of seconds. It can for example be in the order of the time required by an acoustic signal to travel from the emitting to the receiving transducer.
[0025] According to a further embodiment the acoustic signal send by the acoustic signal emitting transducer can be modulated, i.e. its frequency is changed continuously or with step-wise jumps. This facilitates distinction of the acoustic signal over the engine noise and pulsations.
[0026] According to a further embodiment the pulsation pressure is measured as a function of the frequency. This can be done over a wide frequency range until a quit frequency is detected and the frequency of the acoustic signal emitting transducer is tuned to such a quiet frequency, which is free of pulsations and/or engine noise.
[0027] To reduce the energy needed for the speed measurement and to avoid unnecessary additional sound generation the pulsation pressure can be measured at the emitting frequency used for the acoustic signal emitting transducer and the acoustic signal pressure emitted by the acoustic signal emitting transducer is controlled to a predetermined multiple of the pulsation pressure at the emitting frequency. For short distances between the emitting and receiving transducer and when applying noise filtering the sound pressure of the acoustic signal can be smaller than the sound pressure of the engine noise. Preferably a sound pressure of less than 1 time down to 0.3 times the engine noise's sound pressure can be used. In this context, typically a distance of one to three times the flow channel height can be considered as a small distance.
[0028] According to another embodiment the pulsation probe used to monitor combustor pulsations is also used as receiving transducer to determine the speed of sound.
[0029] According to a further embodiment the same transducer is used for emitting of the acoustic signal and for receiving the acoustic signal. In this case the transducer receives the signal reflected by a part of the gas turbine. This can for example be an inner wall of the flow path if the transducer is installed at an outer wall. It can also be reflected at an outer wall if the transducer is installed at an inner wall.
[0030] The use of acoustic temperature measurement has been described for measurements in gases. Typically, those measurements were carried out in air or gases with a given composition. However, in gas turbine operation the boundary conditions including the gas composition can change considerably. For example the oxygen content at the downstream end of a sequential combustor (second combustor) of a gas turbine can be close to the oxygen content of ambient air at part load operation (only reduced by one to two percent) and can be reduced to practically zero at base load operation with flue gas recirculation. Neglecting the changes in gas composition can lead to a noticeable measurement error. To avoid such measurement error it is suggested to determine the gas composition of the gas flowing in the pressurized flow path and to determine the heat capacity ratio □ and/or specific gas constant R spec determined based on the gas composition. The temperature measurement is than based on the determined heat capacity ratio □ and/or specific gas constant R spec .
[0031] Measurement of the gas composition in the pressurized gas path of a gas turbine, in particular of the hot gases of a combustion chamber at required temperature measurement locations is difficult to realize. According to one embodiment for determining a temperature it is therefore suggested to determine or measure the gas composition of the compressor inlet gas, the pressurized gas or the exhaust gas. The measured or determined composition is corrected for changes in compositions due to addition of fluids and/or changes in composition due to combustion between the measurement point and the section in which the speed of acoustic signal is determined.
[0032] Added fluids can for example be a fuel added in a burner, a water or steam flow added in a burner for emission control or power augmentation, a water or steam flow added to a compressor plenum for power augmentation, or water added for inlet cooling and/or high fogging (i.e. an overspray of water into the intake gas beyond saturation, also known as wet compression) into the compressor or upstream of the compressor inlet. Further, the influence of flue gas recirculation (if applicable) on the composition of the inlet gases can be considered.
[0033] If the flue gas composition of the exhaust gases are measured the flue gas composition upstream of a flame can be determined correspondingly by subtracting the influence of fluid added between the measurement point of the gas composition and the cross section at which the gas temperature is determined.
[0034] For indirect determination of the gas composition the added fluid flows and the gas flows inside the gas turbine have to be known. These can change considerably for different operating conditions and can be difficult to determine. Further, the measurement of a gas composition is typically slow and requires a large expensive measurement setup. To avoid expensive measurements of the gas composition and related uncertainties a method of estimating the gas composition based on the measured temperature is proposed.
[0035] According to this embodiment the method for determining a temperature further comprises an approximation for the gas composition. The proposed approximation is used to determine the change in gas composition due to combustion in the pressurized flow path. The change in gas composition is proportional to the amount of fuel burnt. Since the temperature increase due to combustion is also proportional to the amount of fuel burnt, the change in composition can be determined as a function of the temperature increase due to combustion. Based on a starting value for the gas composition and on the measured speed of sound in a cross section downstream of the combustion, the hot gas temperature after combustion can be estimated. This temperature combined with a temperature measurement upstream of the combustion can be used to determine the temperature increase. This temperature increase gives a first iteration on the change of gas composition due to combustion. Based on a known (for example for ambient air), measured or estimated gas composition upstream of the combustion chamber and on the determined change in gas composition an iterated gas composition after combustion can be determined. This leads to a better temperature measurement, which again can be used for iteration of the temperature increase and for the gas composition. This iteration can be repeated until a convergence criterion is met. Typically the convergence criterion is predetermined. It can also be a function of an operating parameter, e.g. a percentage of the operating temperature or of the measured gas composition. It can also depend on the operating condition, e.g. a small value for steady state operation and a larger value for transient operation, such as for example load changes or frequency response operation.
[0036] A starting value for the gas composition can for example be a typical base load composition or estimated based on the relative load of the gas turbine.
[0037] According to one embodiment the iteration for approximating the gas composition of the gas flowing in the pressurized flow path comprises the steps of:
[0038] a) measuring the temperature upstream of the flame,
[0039] b) determining the gas composition upstream of the flame,
[0040] c) taking a starting value for the gas composition downstream of the flame,
[0041] d) determining the heat capacity ratio □ and/or specific gas constant R spec for the starting composition,
[0042] e) determining the hot gas temperature T hot after the flame based on the measured propagation speed of the acoustic signal, the heat capacity ratio □ and specific gas constant R spec for the starting composition,
[0043] f) calculating the temperature increase in the combustor in the flame as a temperature difference □T between the hot gas temperature T hot after the flame and the temperature upstream of the flame T 2 ,
[0044] g) determining the change in gas composition during combustion based on the temperature increase in the combustor □T, a fuel composition and calculating the hot gas composition based on the gas composition upstream of the flame and on the change in gas composition during combustion,
[0045] h) determining corrected iterated heat capacity ratio □ i and/or specific gas constant R spec,i ,
[0046] i) recalculating an iterated hot gas temperature T hot,i after the flame based the iterated heat capacity ratio □ i and/or specific gas constant R spec,i , and
[0047] j) continue iterating at step e) until a convergence criterion is met.
[0048] A convergence criterion can be a difference between the latest iterated gas composition or temperature and the value of the previous iteration. Typically, a change in an iterated value which is smaller than 1% of the absolute value is a sufficient convergence criterion.
[0049] Typically, temperature measurements upstream of a combustion chamber such as a compressor exit temperature are available and reliable. For air breathing gas turbines the inlet gas composition is also known.
[0050] For control and supervision of a gas turbine it is useful to not only know the temperature at a specific location but to determine the temperature average and/or to determine a temperature distribution or temperature profile. According to one embodiment a plurality of transducers is used to determine an average temperature in the cross section and/or to determine a temperature profile in the cross section.
[0051] To avoid interference of acoustic signals send from multiple transducers different frequencies can be used for neighboring emitting transducers. According to one embodiment using multiple transducers to measure the acoustic signal pulsed and/or modulated acoustic signals are used. These can be sent with a time shift or according to a predetermined sequence to enable distinction of the signals traveling different paths.
[0052] Besides the method of determining a temperature based on the measured speed of sound in the in part of flow path of the gas turbine downstream of a compressor and upstream of a turbine, the use of this temperature in a method for controlling a gas turbine is an object of the disclosure.
[0053] Further, a gas turbine configured to carry out a method to determine a temperature and is operated using the temperature is an object of the disclosure.
[0054] According to one embodiment such a gas turbine has at least a compressor, a compressor plenum, a burner, a combustion chamber, a turbine, and a processor for the temperature measurement, and comprises at least one acoustic signal emitting transducer and receiving transducer installed in part of flow path of the gas turbine downstream of a compressor and upstream of a turbine, which is pressurized in operation. For the temperature measurement the processor is configured to send a command to the acoustic signal emitting transducer causing it to send a predetermined acoustic signal across at least a section of a cross section of the pressurized flow path. The receiving transducer is arranged to detect the acoustic signal and to send a corresponding signal to the processor. Further, the processor is configured to calculate the speed of sound based on the measured traveling time and a given distance between acoustic signal emitting transducer and the acoustic signal receiving transducer, and to calculate the temperature of the gas in the section of the pressurized flow path as a function of the speed of sound, and a heat capacity ratio □ and a specific gas constant R spec of the gas provided to the processor.
[0055] According to a further embodiment at least one acoustic signal emitting and receiving transducer is installed the compressor plenum to measure the compressor exit temperature. Additionally or alternatively at least one acoustic signal emitting and receiving transducer is installed in the burner. This allows measurement of the inlet temperature to the burner or combustion chamber before combustion takes place. In a gas turbine with sequential combustion this allows measurement of the exhaust temperature of the first turbine. Additionally or alternatively at least one acoustic signal emitting and receiving transducer is installed in the combustion chamber to measure the hot gas temperature.
[0056] Different arrangements of the acoustic transducers are conceivable. According to one embodiment of the gas turbine at least one acoustic signal emitting transducer is installed on an inner wall of the pressurized flow path and at least one receiving transducer is installed on an outer wall of the pressurized flow path. Alternatively or in combination at least one acoustic signal emitting transducer can be installed on an outer wall of the pressurized flow path and at least one receiving transducer can be installed on an inner wall of the pressurized flow path. In another embodiment the at least one acoustic signal emitting transducer and receiving transducer is installed on an outer wall of the pressurized flow path. In yet another embodiment the least one acoustic signal emitting transducer and at least one receiving transducer is installed on an inner wall of the pressurized flow path.
[0057] In a further embodiment of the gas turbine the processor is configured to determine engine noise level and to filter or separate the pulsation and noise from the acoustic signal.
[0058] For filtering or separating the acoustic signal from the pulsation signal the signal of a receiving transducer is transformed into the frequency ranges for example by Fast Fourier Transform (FFT). This transformation gives a spectrum with a number of frequency bands (amplitudes in a small frequency range). The number of bands can for example be in the range of 100 to 1000, up to 2000 or more bands.
[0059] Preferably the band frequencies are maintained very precisely and the signal permeability within the band, or signal blocking outside the band is ideal as desired in accordance with the utilized system performance (for example computer performance). An “acoustic-frequency signal” in the present context is intended to mean a signal that represents the amplitudes of the acoustic signal in dependence on the frequency. From an acoustic-frequency signal of this type it is particularly easy to obtain specified monitoring frequency bands. Additionally, the frequency bands can be selected ideally narrow in accordance with the utilized system performance (computer performance), permitting a targeted and separate monitoring of certain acoustic frequencies without distorting their amplitudes. The invention, in this context, is also based on the realization that interfering engine noise or pulsation frequencies may lie relatively close to acoustic-signal frequencies, so that a comparatively broad conventional monitoring frequency band, due to the nature of the system, also detects noise or pulsation frequencies and accordingly cannot distinguish the acoustic signal from the pulsation frequencies, and a distortion, especially a swelling, of the amplitudes of certain pulsation frequencies occurs as well. The width of the monitoring frequency bands in the case of an acoustic-time signal by means of conventional band pass filters (Tchebychev or the like) cannot be selected arbitrarily small. Due to the technical characteristics of these band filters, the effect of this is more pronounced, the greater the frequencies that need to be filtered out. The monitoring frequency bands in the case of the acoustic-frequency signal, in contrast, can be selected ideally narrow in accordance with the utilized system performance, so that it is especially possible to exclude closely adjacent pulsation frequencies from the signal monitoring process. Additionally, in a preferred embodiment, a dynamic adaptation of the system parameters (especially band pass limits, time constants, etc.) may be performed to various operating conditions of the gas turbine, for example normal operation, startup, unloading, fuel change, etc.
[0060] Accordingly, a processor configured to determine the engine's combustor pulsation i.e. the combustor pulsation pressure and to separate the pulsation signal from the acoustic signal can transform the signal received from a receiving transmitter into bands and is configured to monitor the amplitude in at least one defined frequency band.
[0061] The global minimum of the amplitude in all intervals of the sound spectrum can be determined and the acoustic signal emitting transducer can be tuned to a frequency in this interval.
[0062] To further enhance the measurement quality and reliability a measurement time window can be defined. The beginning of the measurement window can be triggered by when a pulsed acoustic signal is send from the acoustic signal emitting transducer. The measurement window can start with a time delay taking into account a minimum traveling time of the acoustic signal and end at a maximum traveling time of the acoustic signal.
[0063] The proposed combustor transition can be used for new gas turbines as well as for retrofitting existing gas turbines. A method for retrofitting a gas turbine comprises the steps of opening the gas turbine housing, installing at least one acoustic signal emitting transducer and at least one receiving transducer on a wall of the pressurized flow path, and of closing the gas turbine housing.
[0064] The above gas turbine can be a single combustion gas turbine or a sequential combustion gas turbine as known for example from EP0620363 A1 or EP0718470 A2. The disclosed method and use as well as retrofit method can also be applied to a single combustion gas turbine or a sequential combustion gas turbine.
BRIEF DESCRIPTION OF THE DRAWINGS
[0065] The invention, its nature as well as its advantages, shall be described in more detail below with the aid of the accompanying drawings. Referring to the drawings:
[0066] FIG. 1 schematically shows an example of a gas turbine according to the present invention.
[0067] FIG. 2 a schematically shows the cross section II-II of the first combustion chamber of the gas turbine from FIG. 1 with exemplary arrangements of transducers for measurement of a temperature.
[0068] FIG. 2 b schematically shows the cross section II-II of the first combustion chamber of the gas turbine from FIG. 1 with an exemplary arrangement of transducers for measurement of a temperature profile.
[0069] FIG. 2 c schematically shows the cross section II-II of the first combustion chamber of the gas turbine from FIG. 1 with an exemplary arrangement of transducers for measurement of averaged temperatures.
[0070] FIG. 3 schematically shows the cross section III-III of the sequential combustion chamber of the gas turbine from FIG. 1 with an exemplary arrangement of transducers for measurement of a temperature profile.
[0071] FIG. 4 schematically shows an exemplary arrangement of transducers connected to a processor for determining the temperature upstream of the first or second turbine of a gas turbine.
DETAILED DESCRIPTION
[0072] The same or functionally identical elements are provided with the same designations below. The examples do not constitute any restriction of the invention to such arrangements.
[0073] An exemplary arrangement is schematically shown in FIG. 1 . The gas turbine 10 is supplied with compressor inlet gas 11 . In the gas turbine 10 a compressor 12 is followed by a first combustor comprising a first burner 24 and a first combustion chamber 13 . In the first burner 34 fuel 37 is added to the compressed gas and the mixture burns in the first combustion chamber 13 . Hot combustion gases are fed from the first combustion chamber 13 into a first turbine 14 which is followed by a second combustor comprising a sequential burner 25 (also known as second burner) and a sequential combustion chamber 15 (also known as second combustion chamber). Fuel 37 can be added to the gases leaving the first turbine 14 in the sequential burner 35 and the mixture burns in the sequential combustion chamber 15 . Hot combustion gases are fed from the sequential combustion chamber 15 into a second turbine 16 .
[0074] Steam and/or water 38 can be injected into the first and/or sequential burner for emission control and to increase the power output. Water 36 can also be injected into the compressor or upstream of the compressor for inlet cooling and power augmentation.
[0075] In the example shown in FIG. 1 transducers 20 , 21 are arranged in the compressor plenum 26 , and the sequential burner 25 to measure the inlet temperature of the first, respectively the sequential combustion chamber 13 , 15 . To measure the hot gas temperature at vane one 18 of first turbine 14 , respectively at vane one 19 of the second turbine 16 transducers 20 , 21 are arranged in the downstream end region of first and sequential combustion chamber 13 , 15 , respectively. Transducers 20 are arranged on the inner walls towards the machine axis 28 and transducers 21 are arranged on the outer walls towards the casing 17 of the gas turbine.
[0076] Exhaust gas 17 leaves the second turbine 16 . The exhaust gas 17 is typically used in a heat recovery steam generator to generate steam for cogeneration or for a water steam cycle in a combined cycle (not shown).
[0077] Optionally, part of the exhaust gas 17 can be branched off in a flue gas recirculation 34 (typically downstream of heat recovery steam generator) and admixed to the inlet air 35 . Typically the recirculation 34 comprises a recooler for cooling the recirculated flue gas.
[0078] FIG. 2 a schematically shows the cross section II of the first combustion chamber 13 of the gas turbine 10 from FIG. 1 with first exemplary arrangements of transducers 20 , 21 .
[0079] In a first example the acoustic signal emitting transducers and receiving transducers 20 a, 21 a are arranged on the inner wall 22 , respectively outer wall 24 of the first combustion chamber 13 such that they face each other at the same circumferential position. In each case they are arranged downstream of a first burner 24 .
[0080] In a second example the acoustic signal emitting transducer and receiving transducers 20 b, 21 b are arranged on the inner wall 22 , respectively outer wall 24 of the first combustion chamber 13 such that they face each other at the same on circumferential position. In each case they are arranged downstream and between two first burners 24 .
[0081] In a third example the acoustic signal emitting transducer and receiving transducer is combined in one device 20 c, 21 c. The transducer 20 c is arranged on the inner wall 22 , respectively the transducer 21 c on the outer wall 24 of the first combustion chamber 13 . The acoustic signal send by a transducer 20 c, 21 c is reflected by the opposite side wall facing the transducer, and the reflected acoustic signal is detected by the transducer 20 c, 21 c.
[0082] FIG. 2 b shows a cross section of the first combustion chamber 13 of the gas turbine 10 from FIG. 1 with exemplary arrangements of transducers 20 , 21 for measurement of a temperature profile.
[0083] The acoustic signal emitting transducer 20 can for example be arranged circumferentially distributed along the inner wall 22 of the first combustion chamber 13 . The receiving transducers 21 can for example be arranged circumferentially distributed along the outer wall 23 of the first combustion chamber 13 . For each acoustic signal emitting transducer 20 a plurality of receiving transducers 21 i, ii, ii . . . v is arranged along a section of the outer wall 23 facing a corresponding acoustic signal emitting transducer 20 . The average speed of sound between each acoustic signal emitting transducer 20 and corresponding receiving transducers 21 i, ii, ii . . . v can be measured and the corresponding temperature can be derived, thus leading to a temperature distribution. An average temperature can be calculated based on the individual measurements for the section between the emitting transducer 20 and each receiving transducer 21 i, ii, ii . . . v. For temperature averaging the mass flow passing each section can be used.
[0084] The acoustic signal emitting transducer 21 can also be distributed on the outer wall 23 and the receiving transducers 20 on the inner wall 22 . In an alternative embodiment the plurality of transducers 21 i, ii, ii, v can also be acoustic signal emitting transducer 21 and the transducer 20 a receiving transducer.
[0085] If the acoustic signal from more than one acoustic signal emitting transducer 20 , 21 is received by a receiving transducer 20 , 21 a synchronization of the acoustic signal emitting transducers 20 , 21 can be advantageous to easier allocate the received signal to the emitted acoustic signals. Alternatively a sequenced pulsing of the acoustic signal emitting transducers can be carried out.
[0086] In a further alternative different emitting frequencies are used for the plurality of acoustic signal emitting transducers 20 , 21 .
[0087] For any arrangement with a plurality of acoustic signal emitting transducers different frequencies for the different acoustic signal emitting transducers can be used. Also frequency modulations of the acoustic signal emitting transducers can be applied. The modulations of the different acoustic signal emitting transducers can be time shifted to facilitate allocation of the received signals to the emitting transducers.
[0088] FIG. 2 c shows a cross section of the first combustion chamber 13 of the gas turbine 10 from FIG. 1 with exemplary arrangements of transducers 20 , 21 for measurement of averaged temperatures.
[0089] In this example the acoustic signal emitting transducers 21 a are arranged in opposite locations on the outer wall 23 of the annular cross section of the combustion chamber 13 . Between two acoustic signal emitting transducers 21 a a receiving transducer 21 b is arranged on the outer wall 23 . In this example the flow path of the combustion chamber 13 is high enough that in an equidistant alternating arrangement of two acoustic signal emitting transducers 21 a and two receiving transducers 21 b on the outer wall 23 can be arranged such that each receiving transducer is in a line of sight of the neighboring acoustic signal emitting transducers 21 a. The average speed of sound and thereby the average temperature along each line of sight can be determined with this arrangement. The overall average temperature can be estimated by averaging the temperatures determined for all for sections.
[0090] In FIG. 3 the cross section III-III of the sequential combustion chamber of the gas turbine from FIG. 1 is schematically shown. It shows another exemplary arrangement of transducers 20 , 21 for measurement of a temperature distribution. At a location between every other sequential burner 25 a transducer 21 is arranged on the outer wall and staggered relative to the transducers 20 on the inner wall. The transducers 20 are arranged on the inner wall at a location between every other sequential burner 25 . The acoustic signal emitting transducers can be arranged on the outer wall and the receiving transducers on the inner wall or vice versa. The average temperature can be determined for each section between each acoustic signal emitting transducers 20 , 21 and receiving transducer 20 , 21 for each sequential burner 25 leading to a temperature distribution in circumferential direction. The average hot gas temperature can be calculated based on the individual averages downstream of each sequential burner 25 .
[0091] FIG. 4 shows an exemplary arrangement of transducers connected to a processor for determining the temperature upstream of the vane one 18 , 19 of turbine a gas turbine. The processor 30 controls an acoustic signal emitting transducer 20 arranged on the inner wall 22 of the combustion chamber 13 , 15 of the gas turbine. It is controlled to send a pulsed sound 33 . The receiving transducer 20 , 21 detects the sound pressure on the outer wall 23 of the combustion chamber 13 , 15 converts it into an electric or optical signal and transmits the measured value to the processor 30 . The processor 30 filters the signal corresponding to the emitted acoustic signal. Based on the filtered signal corresponding to the emitted acoustic signal the hot gas temperature 32 is determined and used for the gas turbine control. Based on the acoustic sound level 29 a pulsation signal 31 is determined and used for control and protection of the gas turbine.
[0092] The arrangements shown as example for the first combustor in FIGS. 2 a to 2 c can be directly applied to a second combustor, and the example for FIG. 3 can be directly applied to a first combustor.
[0093] In the FIGS. 2 a ) to 2 c ) and FIG. 3 examples with annular combustion chambers are shown. The disclosed method can analogously be applied to gas turbines with can combustors. Transducers in burners as well as in can combustors do not have to be placed on inner, respectively outer walls but can be placed anywhere on the perimeter of the burner or combustion chamber. | The disclosure relates to a method for determining a temperature in a pressurized flow path of a gas turbine comprising the steps of sending an acoustic signal from an acoustic signal emitting transducer across a section of the pressurized flow path, detecting the acoustic signal with a receiving transducer, measuring the time needed by the acoustic signal to travel from the acoustic signal emitting transducer to the receiving transducer, calculating the speed of sound, and calculating the temperature as a function of the speed of sound, the heat capacity ratio (□) and a specific gas constant (R spec ) of the gas flowing in the pressurized flow path.
Besides the method, a gas turbine with a processor and transducers arranged to carry out such a method is disclosed. | 5 |
The invention concerns a method for rapid loading of large sample supports with a very large number of analyte samples for mass spectrometric analysis using the ionization method of matrix-assisted desorption by laser bombardment (MALDI).
The invention consists of using microtiter plates already introduced in biochemistry and molecular genetics for parallel processing of a large number of dissolved samples and a multiple pipette unit for simultaneous transfer of sample solution quantities from all reaction wells on a microtiter plate to the sample support, the sample support having at least the same size. By repeated loading with samples from other microtiter plates, spaced between the samples already applied, a very high density of samples can be achieved. Some of these samples can be reserved for a mass spectrometric determination of the sample positioning on the sample support, and the positions of the other samples can then be interpolated.
PRIOR ART
The ionization of biomolecular or polymer samples using matrix-assisted desorption by means of bombardment with short flashes from a pulsed laser has found wide acceptance in recent years and is used especially for time-of-flight mass spectrometers, but also in quadrupole RF ion traps or in ion cyclotron resonance spectrometers. This method is called "MALDI" (matrix-assisted laser desorption/ionization). This ionization method requires that samples applied to the surface of a sample support must be introduced into the vacuum system of the mass spectrometer. Prior art here is that a relatively large number of samples (about 10 to 100) are introduced together on a support, and the sample support is moved within the vacuum system in such a way that the required sample is situated specifically in the focus of the laser's lens system.
The analyte samples are placed on a sample support in the form of small drops of a solution, the drops drying very quickly and leaving a sample spot suitable for MALDI. Normally a matrix substance is added to the solution for the MALDI process and the sample substances are encased in the crystals when the matrix substance crystallizes while drying. However, other methods have also become known by which the sample substances are applied to a matrix layer which has been applied first and is already dry.
Current methods with visual control by the user via microscopic observation of the sample spots do not allow automation, but due to rapid progress in the MALDI technique, an automation of the sample ionization is emerging. Automation opens up the long demanded possibility for a processing of several tens of thousands of samples per day in mass spectrometer analysis. Parallel processing of large numbers of samples was introduced long ago in other areas of biochemistry and molecular genetics. For this goal, larger sample supports than used nowadays will be required, and a high densities of analyte samples on the sample support are demanded.
In biochemistry and molecular genetics, so-called microtiter plates have become established for parallel processing of many samples. The body size of these plates is 80 by 125 millimeters, with a usable surface of 72 by 108 millimeters. Today there are already commercially available sample processing systems which work with microtiter plates of this size. These originally contained 96 small exchangeable reaction vials in a 9 mm grid on a usable surface of 72 by 108 millimeters. Today, plates of the same size with 384 reaction wells imbedded solidly in plastic in a 4.5 mm grid have become standard. Plates with 864 reaction wells in a 3 mm grid are being discussed.
The parallel processing of high numbers of samples, for example in molecular genetics, consists not only in working with just one such microtiter plate, but rather in parallel working with a large number of such plates. For example, with simultaneous treatment of 120 such plates in a single PCR apparatus (PCR=polymerase chain reaction), more than 46,000 DNA segments could be multiplied a billion times simultaneously within a period of about 3 hours.
As yet, various sample supports with up to 30 millimeters diameter, in other systems up to 50 by 50 millimeters in size, are being used in commercial mass spectrometry. These appear too small for future requirements. Currently investigated trends indicate that tens of thousands of samples will be be analyzed daily if analyses can be automated.
Different types of sample supports can be used for automatic sample analyses. High numbers of smaller sample supports, for example, can be automatically fed to a mass spectrometer as described in U.S. Pat. No. 5,498,545. Such an automatic system is nevertheless complicated and it appears much more practical to locate tens of thousands of samples on a single sample support.
The number of samples on a sample support is mostly limited today by the long time required for loading of the samples on the support and by the perishability of the samples during this period of time. If about 40,000 analysis samples must be applied in sequence to a single sample support, and the application of each sample lasts only two seconds (although the transfer pipette can hardly be properly cleaned during this time), the entire loading process then lasts already more than 22 hours. For many MALDI methods, matrix substances are used which oxidize or hydrolize when exposed for long periods to wet air and thereby lose their effectiveness for the MALDI process. Also the biomolecular samples are often unstable, and sometimes must be stored cooled in solution and cannot be exposed for hours to laboratory air and heat.
Mass spectrometric analyses with parallel treatment of large numbers of samples are needed for genotyping, for determining individual gene mutations and for many other problems.
OBJECTIVE OF THE INVENTION
It is the objective of the invention to find a method with which appropriate sample supports can be loaded relatively quickly and safely with thousands of MALDI analyte samples, processed from initial samples in microtiter plates, so that they are accessible for automatic mass spectrometric analysis procedures.
DESCRIPTION OF THE INVENTION
It is the basic idea of the invention to adapt the sample support in its size and shape to microtiter plates, to preprepare it with a MALDI layer and to transfer all (for example 384) or at least a large subset of analyte samples from one microtiter plate onto the MALDI layer at the same time. Suitable for this transfer is the well-known multiple pipette unit which either has exactly as many pipettes as the microtiter plates has reaction wells, or at least a large subarray of pipettes. The array of micropipettes must possess the same spot spacing as the reaction wells on the microtiter plate, or an integer multiple thereof. When using microtiter plates with 384 analysis samples, preferredly all 384 samples may be transferred at the same time and placed in a sample spot array with 4.5 millimeter spot spacing on the MALDI layer. As an alternative, a multipipette with 96 pipette tips may be used, yielding a sample spot array with 9 millimeter spot spacing, but necessitating four sample transfers from one 384-well microtiter plate.
By cleaning the multipipettes, changing the microtiter plates and repeating this procedure, a second sample spot array with another 384 analysis samples from a second microtiter plate can be applied to the same sample support, whereby this sample spot array is just slightly offset (interlaced) from the first array. By repeating this procedure, 384 sample blocks (or, in the case of a 96-tip multipipette, 96 sample blocks) can be created on a sample support, while each sample point block contains a large number of sample spots each of which comes from a different microtiter plate.
For example, with a block of 5 by 5 sample spots and using a 384-well microtiterplate and a 384-tip pipette, a total of 5×5×384=9,600 samples can be applied while the sample spots can be spaced at a maximum of 0.9 millimeters from one another. The sample spots can each have a diameter of about 0.6 millimeters without problem. It is even possible to apply blocks of 11 by 11 sample spots with 400 micrometers of spacing and 300 micrometers diameter for each sample spot. This produces a total load of 46,464 samples on a single sample support plate. As shown below, even many more analysis samples can be applied.
The sample support can be provided with a lacquer layer of nitrocellulose, for example, as a preparation for the MALDI process, a suitable protonizing matrix component being added to the lacquer. Such coatings have been described in patent applications DE 19 617 011 and DE 19 618 032. This lacquer layer is extremely adsorptive for proteins and DNA. The molecules of the analyte substance are adsorbed very uniformly on the surface and thus allow automation of the MALDI ionization process. The lacquer layer partially decomposes during bombardment with laser light flashes in the focal area of the laser light, thus releasing the biomolecules without causing them to fragmentate. The hot gases from the explosion-like decomposition are cooled by adiabatic expansion in the surrounding vacuum so quickly that the large biomolecules are barely heated up. Ions from the added protonizing matrix component then react in the gas phase with the large biomolecules and cause their ionization. The biomolecules may also however be chemically pretreated so that they already carry a charge in a solid condition and thus are released mainly as ions. The analyte ions are then analyzed in the mass spectrometer, for example (as in the simplest case) for their molecular weight.
The multiple pipette unit contains the pipettes exactly in the spacing of the array of reaction wells on the microtiter plate (or in integer multiples of the distances). The pipettes can therefore reach into the reaction containers with spatial precision and synchronicity and take out the solution there. They can, for example, terminate in small steel capillaries of 200 micrometers in outside diameter which are arranged in conically pointed holders with extreme precision in the grid of the microtiter plates of 4.5 millimeters. With them, very precise sample spots of 200 micrometers diameter are produced on the MALDI layer of the sample support which are arranged exactly in the grid of the microtiter plate. The amount of sample in those spots is by far sufficient for a single mass spectrometric analysis. The pipettes can be designed as a large number of individual microliter syringes with synchronous movement of the plungers.
Much simpler however are passive pipettes which function rather like imprinting stamps. They may consist, for example, of small stainless steel wires of 200 micrometers diameter without an inner capillary aperture, again fitted into conically pointed holders. The very slightly hydrophilic pipette wires take up tiny droplets, very precisely dosed, from the sample solution which hang from the end of the wires, and apply them to the MALDI layer on the sample support using gravitation and capillary forces. The MALDI layer is slightly hydrophobic, therefore the drops do not spread out on the layer and can be dried to a sample spot of about 200 micrometers in diameter.
These passive pipette tips can be coated on the end with appropriate layers, for example with a layer which attracts the sample molecules to the surface and therefore removes them in greater concentrations from the sample solution. If the adsorptivity of this layer is less than that of the MALDI layer on the sample support, the sample molecules can again be preferentially deposited on the MALDI layer.
It is a further idea of the invention that positively or negatively charged analyte molecules in the solution are attracted via electrophoretic migration to the passive pipette wires and can be concentrated there in this way by supplying the pipette wires with an electrical voltage in relation to the microtiter containers. The counterelectrodes may be integrated into the walls of the containers (for example through semiconductive walls), however they may also be introduced separately from the multipipette unit by separate extra electrode tips. The droplets taken then contain considerably more analysis molecules than actually correspond to the concentration of analysis molecules in the solution found in the microtiter wells. Chemical decomposition of the sample molecules on the pipette wires can be avoided by a suitable coating. The sample molecules transported with the droplet onto the MALDI layer can be transferred to the MALDI layer by reversing the electrophoresis voltage.
These multiple pipette systems are moved by an automatic robot system in three axes. They have relatively long routes to cover and must therefore be able to move quite quickly. They must move at least from the microtiter plate to the sample support, from there to a wash and dry station and back again to a new microtiter plate. Due to these requirements, their positioning accuracy is limited, but at a reasonable cost, systems may be built which have a positioning accuracy of about 50 micrometers.
This positioning accuracy of present automated pipette handlers of about 100 micrometers already allows the above mentioned sample blocks of 11 by 11 sample spots with 400 micrometers sample spot grid and 200 micrometers sample spot diameter, however it is then necessary to check the position of the sample spots relative to each other by suitable methods inside the mass spectrometer. To do this, at least two sample blocks with suitable, easily ionizable reference substances are necessary which should be as far apart as possible. With these two sample blocks, the positions of the individual samples in regard to one another can be determined in the mass spectrometer by a thorough scanning procedure. From the positions of the sample points in two sample blocks, the positions of all other sample blocks can be interpolated, even if beside the parallel offset there should be an angular offset.
It is therefore a further idea of the invention to provide at least two sample blocks with suitable samples for the measurement of the positioning of the samples inside the blocks. It would be best if these sample blocks were provided with samples of known substances with high ionization yield in order to ease scanning. For security reasons, it is practical to provide not only two but four blocks for this and to use the blocks in the four comers of a sample support. 380 sample blocks still remain for the analyses of unknown substances.
A further aspect concerns quality control. It has to be secured that the correct sample spot on the carrier plate is being analysed, and the best alignment of the mass spectrometer has to be checked in relatively short time intervals. It is therefore a further reference substance in known concentration and thus have a control for correct mass measurement and correct overall sensitivity of the apparatus. When using the four comer blocks for position calibration, and one sample each from every 11×11 block for mass and sensitivity control, there are still 45,600 analyte samples remaining. The following table provides an overview of the number of utilizable analysis samples relative to the block size, if 384-well microtiter plates and 384-tip multipipettes are used:
______________________________________Samples per block Maximum spacing Number of utilizable(number of microtiter plates) (center to center) analyte samples______________________________________2 × 2 = 4 2,00 mm 1 1403 × 3 = 9 1,50 mm 3 0404 × 4 = 16 1,12 mm 5 7005 × 5 = 25 0,90 mm 9 1206 × 6 = 36 0,75 mm 13 3007 × 7 = 49 0,64 mm 18 2408 × 8 = 64 0,56 mm 23 9409 × 9 = 81 0,50 mm 30 40010 × 10 = 100 0,45 mm 37 62011 × 11 = 121 0,40 mm 45 60012 × 12 = 144 0,37 mm 54 34013 × 13 = 169 0,34 mm 63 84014 × 14 = 196 0,32 mm 74 10015 × 15 = 225 0,30 mm 85 120______________________________________
Naturally, as a deviation from the table, non-square blocks can be used if this appears more favorable, for example positioning accuracy is not the same in the x and y direction.
The values on the table are all consistent with a position inaccuracy of 0.05 millimeters at a sample spot diameter of 0.20 millimeters. Naturally, the spot diameter could be selected much higher for 3×3 samples per block. At an average time of one minute for a loading cycle, the sample support for the samples from 11×11=121 microtiter plates is loaded in about two hours, for 15×15=225 microtiter plates in less than four hours. For a 96-tip multipipette, the loading times have to be multiplied by four.
It can happen that sensitive samples cannot be exposed to the air for long. This can become a problem during lengthy loading times. In this case it is possible to fill the entire loading apparatus with protective gas and then also transport the sample support plates covered in protective gas to the mass spectrometer. In the concurrent patent application DE 19 628 112, a cassette design is presented in which the sample support can be stored, transferred and fed into the mass spectrometer in protective gas.
Of course, the invention may also be applied analogously to other microtiter plates with other grid spacings.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 shows a section of a multiple pipette unit (1) above a section from a microtiter plate (4). The individual pipettes have shafts (2) with conically pointed ends holding the pipette capillaries (3). The pipettes can be introduced into the recessed reaction wells (5) on the microtiter plate (4).
FIG. 2 shows a comer section of the sample support (6) after loading with samples. The sample spots are arranged in array blocks (10) of 5×5 sample spots each. The array blocks have a spacing from each other which corresponds to that of the reaction wells on the microtiter plate. The 25 samples in a sample array block (10) each originate from a different microtiter plate. The sample spots do not form an exactly positioned 5×5 array, since the positioning of the multiple pipette unit was not exactly accurate when applying the samples. The relative positioning within adjacent 5×5 blocks is nevertheless the same, due to the accuracy of the multipipette.
Therefore the position of all sample spots can be determined exactly by a measuring scan of one such block in the mass spectrometer, if only a parallel offset of the spots is to be expected. If an angular offset is also to be expected, two blocks must be measured. The block with the sample spots (7) in the comer of the sample support consists of reference substances which can easily be scanned for such position calibration. The white sample spots (9) are reference substances which allow an overall quality control. The black sample spots (8) are the unknown analysis samples.
Particularly favorable embodiments
The sample supports, according to this invention, conform precisely in their size to the microtiter plates. They can then be introduced and processed in commercially available processing stations for microtiter plates. These stations have become established in biochemistry for parallel processing of many samples; they are commercially available. The body size of these plates is 80 by 125 millimeters, with a usable surface of 72 by 108 millimeters, on which today usually 384 reaction wells (vials) are solidly recessed into the plastic in a 4.5 mm grid.
If microtiter plates with 864 reaction wells in a 3 mm grid are introduced in the future, these may also be used since they are the same size. Then the multipipette units and sample spot array for the sample blocks must be changed. Loading will then be faster since 864 samples each can be transferred at the same time.--If 96-tip multipipettes are used, these can readily handle 864-well microtiter plates, if only the shaft diameter is smaller than the well diameter. Nine sample transfer processes are then needed for each of the microtiter plates.
The invention is based upon the already introduced parallel processing of large numbers of samples in biochemistry and molecular genetics. The handling stations used here for the loading process are also being used for the preparation of the samples to be analyzed.
The sample supports in the size of microtiter plates must be provided with a MALDI layer. This can be done in the biochemical laboratory, however in the future it will preferably be done by industrial prepreparation. The MALDI layer may consist of a lacquer-like layer of nitrocellulose, for example, a suitable protonizing matrix component being added to the lacquer.
This lacquer layer is extraordinarily adsorptive for peptides, proteins and DNA. The molecules of the analysis substances are adsorbed very uniformly on the surface and thus allow automation of the MALDI ionization.
This layer must now be covered with the arrays of samples which were prepared in the microliter plates. Suitable for this are the well-known multiple pipette units. However, whereas to-day's multipipettes have only single rows of pipettes, here multipipettes with twodimensional arrays of pipettes are proposed, the individual pipettes of which are arranged in the grid pattern of the reaction wells of the microtiter plates.
The simplest embodiment of a multiple pipette unit consists of a plate into which pins have been screwed in the grid pattern of the reaction containers on the microtiter plates. In the conically pointed ends of the pins pipette wires have been inserted. The pipette wires project only slightly, about one or two millimeters, from the pin shaft, to prevent maladjustment. The wires are ground off in such a way that their ends are exactly in plane. When they dip into the reaction wells, filled to exactly the same height, on the microtiter plate, they are wetted in the same manner with sample solution, taking equal amounts of sample solution with them when they are lifted out. The diameter of the pipette wires determines the future size of the sample spot on the sample support.
The multiple pipette unit can also carry capillary pipettes, which have a design similar to microliter syringes. Using them, larger amounts of sample solution can be transferred.
The transfer to the sample support must be done very precisely. It can hardly be performed manually. Here the obvious solution is an automatic movement mechanism which can move the multiple pipette unit three-dimensionally with great accuracy. Such movement units can be constructed using linear motors, and they can run through paths of about one meter in length at speeds of about 20 meters per second with a positioning accuracy of 50 micrometers. The movement units may also have a robot hand besides the multiple pipette unit which can bring the microtiter plates from a magazine to a fixed intermediate station.
Using such a movement unit, the loading process of a sample support located in a support station can be performed using the following cycle according to this invention:
The robot hand picks up the first microtiter plate from a magazine, in which there are about 60 microtiter plates, and positions it precisely in the intermediate station. Each of the microtiter plates contains suitable reference samples of known concentration in the four comer wells. Then the multiple pipette unit is introduced into the reaction wells of the microtiter plate, whereby the pipette wires are wetted. The pipette unit is lifted out leaving solution droplets of about 200 micrometers diameter on the pipette wires. The pipette unit is then moved to the MALDI support plate station and after as accurate a positioning as possible, and after the remaining vibrations have ceased, it is lowered to about 50 micrometers above the sample support. The droplets then touch the MALDI layer on the sample support. During the subsequent lifting away of the pipette unit, the larger shares of the droplets remain on the MALDI layer, which then dry under the influence of dry, warm air within about 30 seconds.
The pipette unit is then moved to a washing station where it is cleaned in water which has been acidified with trifluoroacetic acid and in which there are also brushes to rub off residual sample material. The movement unit can move the pipette unit over the fixed brushes in a washing action. The second washing station consists of clean water. Then the pipettes are dried in a stream of warm, dry air.
In the next step, the robot hand returns the microtiter plate to the magazine and takes the next plate. The complete cycle lasts about 60 seconds. The cycle can be repeated as often as necessary until the sample support is completely loaded or the magazine with microtiter plates is empty. This must then be replaced with the next magazine.
The point patterns must be applied slightly offset for each of the microtiter plates, so that the sample array blocks result as shown in FIG. 2. The blocks shown there with 24 analysis samples and a reference sample produce exactly 9,120 analyte samples applied in only 25 minutes on the basis of 380 reaction wells per microtiter plate. This may be enough for many purposes. For this number, replacement of the magazine is unnecessary, and loading can take place completely automatically. Even using a 96-tip multipipette instead of the 384-tip pipette, the loading process takes only about two hours.
If higher numbers of analyses are required, for example for medical screening analyses in searching for dangerous mutations, sample blocks with 11×11=121 sample spots can be applied. Here it is advisable, for increased safety, to apply the samples twice on different positions and again use one reference substance per block. Therefore samples from 60 microtiter plates with analytes and one microtiter plate with reference substance are taken, and again only one magazine is necessary, and the loading can take place again completely automatically without interruption. The loading for this takes about two hours.
Generally, the completely loaded sample supports must be treated further before analysis in a mass spectrometer. It is advisable to wash the sample supports in order to remove all salts and buffer substances from the surface. The molecules from the biochemical analysis substances are generally so firmly adsorbed that they are not removed during a careful washing procedure. It may also be necessary in borderline cases to remove all metal ions from the surface with special chemical or physical agents, because they sometimes tend to form adduct compounds. The carder plate must then be well dried so that not too much water is introduced into the mass spectrometer.
The sample supports are then introduced into the ion source of a suitable mass spectrometer and analyzed there. In the case of 11×11 sample spots, 22,800 samples must then be analyzed, a double measurement being undertaken for every sample. The total of 45,600 analyses can be performed in 25.3 hours if every analysis lasts exactly 2 seconds. Additional time is necessary for the position scanning and for analysis of the reference samples. To perform the analyses in somewhat less than one day, it is therefore practical to achieve analysis times below 2 seconds.
For easily degradable samples it may be necessary to carry out the entire loading process, for example, in an automatic device sealed with large glass panels under protective gas, e.g., nitrogen. Even the transportation of the ready loaded sample support plates to the mass spectrometer can be done under protective gas, using suitable cassettes.
The pipette tips can also be provided with suitable coatings which attract sample molecules for enrichment of the sample molecules. Also an electrophoretic enrichment can be applied. The attracted sample molecules can also be transferred using electrophoretic voltage to the MALDI layer. | A method for rapid loading of large sample supports with a very large number of analyte samples for mass spectrometric analysis using the ionization method of matrix-assisted desorption by laser bombardment (MALDI). The method consists of using microtiter plates already introduced in biochemistry and molecular genetics for parallel processing of a large number of dissolved samples and a multiple pipette unit for simultaneous transfer of sample solution quantities from all reaction wells on a microtiter plate to the sample support, the sample support having at least the same size. By repeated loading with samples from other microtiter plates, spaced between the samples already applied, a very high density of samples can be achieved. Some of these samples can be reserved for a mass spectrometric determination of the sample positioning on the sample support, and the positions of the other samples can then be interpolated. | 1 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to and the benefit of Korean Patent Application No. 10-2012-0003295 filed in the Korean Intellectual Property Office on Jan. 11, 2012, the entire contents of which are incorporated herein by reference.
TECHNICAL FIELD
[0002] The present invention relates to a method for analyzing a structure of lines that form a character and representing a stroke formed in a predetermined order in order to recognize the character formed of various fonts appearing in an outside environment to increase the precision of character recognition.
BACKGROUND ART
[0003] A structural character recognition method according to a related art is usually used for online input. That is, stroke information of a character which is information detected by an electronic pen or touch is continuously and sequentially received and the structural features of the strokes are analyzed and modeled to recognize the information. Even when individuals have various note-taking habits, the structures of the strokes are uniform so that the above structural character recognition method is preferable.
[0004] In contrast, when the characters input from an image are recognized (OCR), a statistic recognition method using a neural network is mainly used. When a font is uniform or limited, the statistic recognition method has high recognition rate and is mainly used for text recognition using a scanner. However, in case of a character included in an external image of a natural environment having no specific font, the statistic recognition method is not suitable for a recognition method because it is hard to train various changes of fonts and thus the high recognition rate may not be expected.
SUMMARY OF THE INVENTION
[0005] The present invention has been made in an effort to provide a method of pre-processing character information included in a natural scene using a structural character recognition method which is mainly used in an on-line recognition method in order to recognize characters configured by various fonts present in the natural scene, detecting the structural feature point including an end point and a divergence point of the pre-processed character information, and then assigning the corresponding structural feature code thereto to generate as a numeral string.
[0006] An exemplary embodiment of the present invention provides a method of sequencing character information, including a pre-processing step in which a pre-processing unit extracts character information from an image to binarize the extracted character information through a predetermined threshold value and thins the binarized character information to be information with a predetermined thickness; a step in which a normalizing unit normalizes the character information pre-processed in the pre-processing step to character information according to a predetermined criteria; and a sequencing step in which a sequencing unit converts the normalized character information into information numeralized using structural features including an end point or a divergence point of the character information.
[0007] The normalizing of the character information includes: a step in which an end point code assigning unit detects an end point of a character stroke having one adjacent point among points configuring the pre-processed character information; and a step in which a character information rotating unit corrects an inclined angle of the character information using the detected end point in accordance with a predetermined direction.
[0008] The step of detecting the end point preferably includes: a step in which the end point code assigning unit assigns an end point code to the end point detected from the character information; and a step in which the end point code assigning unit sets a visiting order of end points according to a predetermined order for end points to which the end point codes are assigned.
[0009] In the step of correcting the inclined angle, a character information rotating unit rotates the character information in a direction where an angle formed by a reference point and predetermined n directions using one of the detected end points as the reference point is minimized.
[0010] Before the step of sequencing using the structural feature, the method further includes a step in which the code assigning unit assigns a chain code that indicates a heading direction of a stroke or a divergence point that indicates the crossing of the strokes to each of points configuring the normalized character information. In the step of sequencing, the sequencing unit sequences the character information to which the code or the point is assigned using the structural feature.
[0011] The chain code or the divergence point is assigned such that the code assigning unit visits each of the points configuring the character information in accordance with a predetermined visiting order to assign the chain code or the divergence point to the detected end points.
[0012] The chain code or the divergence point is assigned such that when no end point is detected in the step of detecting the end point, the code assigning unit visits the points using a point that is positioned relatively at a left-upper most side, among the points included in the character information, as a starting point in accordance with a predetermined visiting order to assign the chain code or the divergence point.
[0013] The points of the character information are visited in accordance with the set or determined visiting order such that the code assigning unit visits continuous points to the starting point using a depth first search method that a point whose relative position is the left-upper most has a priority.
[0014] In the step of assigning the chain code or the divergence point, the code assigning unit assigns a curved point to a visited point when an angle formed by a current heading direction of a stroke and a subsequent heading direction of the stroke is larger than a predetermined threshold value with respect to the visited point in accordance with the visiting order.
[0015] The angle that is compared with the threshold value is a smaller angle of angles formed by the current heading direction of the stroke and the subsequent heading direction of the stroke.
[0016] The sequencing step includes: a structural feature code setting step in which a structural feature code generating unit sets a numeral code corresponding to an end point code, a divergence point or a curved point assigned to the structural feature of the character information; and a numeral string generating step in which a numeral string generating unit generates a structural feature code which is converted into a numeral string by applying a weight to the set structural feature code.
[0017] In the structural feature code generating step, the structural feature code generating unit sets the structural feature as the numeral code in accordance with a predetermined numeralization representation method.
[0018] In the numeral string generating step, the numeral string generating unit sequences the numeral code assigned to the character information in accordance with the visiting order to generate a numeral string.
[0019] The weight is applied in the numeral string generating step such that the numeral string generating unit repeats the numeral codes set for the structural feature of the generated numeral string using a distance between the structural feature positions.
[0020] The method further includes: a modeling step in which a modeling unit generalizes a numeral string for the character information using the numeral string generated in the sequencing step.
[0021] Another exemplary embodiment of the present invention provides an apparatus of sequencing character information, including: a pre-processing unit that extracts character information from an image to binarize the extracted character information through a predetermined threshold value and thins the binarized character information to be information with a predetermined thickness; a normalizing unit that normalizes the character information pre-processed in the pre-processing unit to character information according to a predetermined criteria; a code assigning unit that assigns a chain code that indicates a heading direction of a stroke or a divergence point that indicates the crossing of the strokes to each of points configuring the normalized character information; and a sequencing unit that converts the character information to which the code or the point is assigned into information numeralized using structural features including an end point or a divergence point of the character information.
[0022] The normalizing unit includes: an end point code assigning unit that detects an end point of a character stroke having one adjacent point among points configuring the pre-processed character information to assign an end code; and a character information rotating unit that corrects an inclined angle of the character information in accordance with a predetermined angle using an end point to which the end point code is assigned.
[0023] The sequencing unit includes: a structural feature code generating unit that sets a numeral code corresponding to an end point code, a divergence point, or a curved point that is assigned for the structural feature of the character information; and a numeral string generating unit that applies a weight to the generated structural feature code to generate a structural feature code which is converted into a numeral string.
[0024] The apparatus further includes: a modeling unit that generalizes a numeral string for the character information using the numeral string generated in the sequencing step.
[0025] Yet another exemplary embodiment of the present invention provides a method of recognizing character information, including:
[0026] a step in which a character information inputting unit receives image information including character information; a pre-processing step in which a pre-processing unit extracts character information from the input image information to binarize the extracted character information through a predetermined threshold value and extract and thin a center line of the binarized character information; and a step in which a character information recognizing unit applies a weight to a structural feature point including an end point, a divergence point, and a curved point to convert the character information into numeral string information in accordance with a predetermined algorithm to recognize the pre-processed character information using trained modeling information.
[0027] According to exemplary embodiments of the present invention, an on-line character recognition method according to a related art may be applied to a method of recognizing an off-line character obtained from an image so that characters having various fonts that are present in a natural environment are easily recognized. Further, in order to apply the advantages of structural character recognition regardless of the font to the character information input from the image, the present invention suggests an angle normalization method of input character strings, a structural feature position determining method, and a structural feature numeral string generating method to strongly recognize characters configured by various fonts obtained from a natural scene regardless of an angle or a size of the characters.
[0028] The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0029] FIG. 1 is a flowchart illustrating a method sequencing of character information according to an exemplary embodiment of the present invention.
[0030] FIG. 2 is a flowchart illustrating a normalizing step of character information according to an exemplary embodiment of the present invention.
[0031] FIG. 3A is an exemplary view illustrating a 3 by 3 mask for detecting an end point of character information according to an exemplary embodiment of the present invention.
[0032] FIG. 3B is an exemplary view illustrating an example that an end point code of the character information is assigned according to an exemplary embodiment of the present invention.
[0033] FIG. 3C is an exemplary view illustrating an example that an order according to a predetermined order is assigned to an end point code of the character information according to an exemplary embodiment of the present invention.
[0034] FIG. 4 is an exemplary view illustrating an example of calculating an angle for correcting an angle of character information according to an exemplary embodiment of the present invention.
[0035] FIG. 5 is a flowchart illustrating a method of assigning a code or a point according to an exemplary embodiment of the present invention.
[0036] FIG. 6A is an exemplary view illustrating an eight way code for assigning a chain code according to an exemplary embodiment of the present invention.
[0037] FIG. 6B is an exemplary view illustrating a mask for determining a divergence point according to an exemplary embodiment of the present invention.
[0038] FIG. 6C is an exemplary view illustrating a 5 by 5 mask for determining a curved point according to an exemplary embodiment of the present invention.
[0039] FIGS. 7A and 7B is an exemplary view illustrating a result that a code and a point are assigned to character information according to an exemplary embodiment of the present invention.
[0040] FIG. 8 is an exemplary view illustrating an example that a structural feature code is assigned to a structural feature point of character information according to an exemplary embodiment of the present invention.
[0041] FIG. 9 is a flowchart illustrating of a process of sequencing character information as a structural feature code according to an exemplary embodiment of the present invention.
[0042] FIG. 10 is an exemplary view illustrating a number string generated in a number string generating step of character information according to an exemplary embodiment of the present invention.
[0043] FIG. 11 is an exemplary view illustrating a number string in which a weight is applied to a structural feature code of the number string generated according to an exemplary embodiment of the present invention.
[0044] FIG. 12 is a block diagram illustrating an apparatus of sequencing character information according to an exemplary embodiment of the present invention.
[0045] It should be understood that the appended drawings are not necessarily to scale, presenting a somewhat simplified representation of various features illustrative of the basic principles of the invention. The specific design features of the present invention as disclosed herein, including, for example, specific dimensions, orientations, locations, and shapes will be determined in part by the particular intended application and use environment.
[0046] In the figures, reference numbers refer to the same or equivalent parts of the present invention throughout the several figures of the drawing.
DETAILED DESCRIPTION
[0047] Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. First of all, we should note that in giving reference numerals to elements of each drawing, like reference numerals refer to like elements even though like elements are shown in different drawings. In describing the present invention, well-known functions or constructions will not be described in detail since they may unnecessarily obscure the understanding of the present invention. It should be understood that although exemplary embodiment of the present invention are described hereafter, the spirit of the present invention is not limited thereto and may be changed and modified in various ways by those skilled in the art.
[0048] FIG. 1 is a flowchart illustrating a method of sequencing character information according to an exemplary embodiment of the present invention.
[0049] Referring to FIG. 1 , a method of sequencing character information according to an exemplary embodiment of the present invention includes a pre-processing step S 100 in which a pre-processing unit 110 receives character information included in image information to perform a binarization and thinning process on the character information, a normalizing step S 200 in which a normalizing unit 200 normalizes the pre-processed character information, a step S 300 in which a code assigning unit 300 assigns a point to the normalized character information, and a step S 400 in which a sequencing unit 400 sequences structural features including an end point or a divergence point using a point that is assigned to the normalized character information.
[0050] In the pre-processing step S 100 of the character information, the pre-processing unit 110 receives the character information included in the image information to binarize the character information and thin the binarized information. The binarization of the character information is a process of setting a pixel having a lower value than a threshold value to a black (0) and a pixel having a higher value than a threshold value to a white (255) and preferably represents the image information with contrast of black and white. The binarization according to the present embodiment may include a P-Tile method (simple threshold method), a mode method, average binarization, iterative binarization, and adaptive binarization. According to the P-Tile method, an area percentage point P % in a contrast histogram is set as a threshold value when the area percentage occupied by the object in the image is known. According to the mode method, a contrast point corresponding to a valley between peaks in the histogram that represents a distribution of pixel values according to the contrast value is set as a threshold value of binarization. In the average binarization, an average of all pixels in the image is calculated and set as a threshold value. In the iterative binarization, an approximate threshold value is set as a starting point and then the threshold value is gradually and repeatedly improved. In the adaptive binarization, a histogram for a part of an image rather than a histogram for the entire image is used to calculate a threshold value for the part of an image.
[0051] The character information is thinned such that the information concerning lines included in the binarized character information is converted into lines having a predetermined thickness. More specifically, the thick lines included in the character information are converted into information concerning lines that form one pixel to extract a center line having a thickness that is formed by one pixel.
[0052] The normalizing step S 200 of the pre-processed character information is a step in which the normalizing unit 200 converts the pre-processed character information into information that is normalized in accordance with a predetermined criteria. The normalizing step S 200 will be described in detail with reference to FIG. 2 .
[0053] FIG. 2 is a flowchart illustrating the normalizing step S 200 of character information according to an exemplary embodiment of the present invention. Referring to FIG. 2 , the normalizing method of character information according to the exemplary embodiment includes a step S 210 in which an end point code assigning unit 210 detects an end point of a stroke that configures a character included in the character information and a character information correcting step S 220 in which a character information rotating unit 220 corrects an inclined angle of character information using the detected end point. The end point code detecting step includes a step S 212 in which the end point code assigning unit 210 detects the end point code to assign an end point code and a visiting order setting step S 214 in which the end point code assigning unit 210 to which the end point code is assigned sets an order of visiting the end points.
[0054] The end point code assigning step S 212 is a step in which the end point code assigning unit 210 detects an end point of a stroke included in the character information and assigns an end point code indicating that the detected point is an end point. The detecting of the end point according to the exemplary embodiment will be described with reference to FIG. 3A . The end point is preferably a position having only one adjacent point when eight directions are searched using itself as a reference point in the stroke included in the character information. The end point is preferably detected by scanning all points configuring the strokes included in the character information using 3 by 3 masks shown in FIG. 3A . When one point among points corresponding to eight directions of A with respect to one point E exists, the point is preferably the end point. An end point code that indicates the end point is preferably assigned to the detected end point. FIG. 3B is an exemplary view illustrating an example of the character information to which an end point code is assigned according to an exemplary embodiment of the present invention. FIG. 3B shows that an end point code E is assigned into four end points detected from the character information.
[0055] The step S 214 in which the end point code assigning unit 210 sets the order of visiting the end point of the character information to which the end point code is assigned sets the visiting order in accordance with a predetermined order of the end points in which the end point codes are set. The visiting order in accordance with the predetermined order will be described in detail with reference to FIG. 3C . Referring to FIG. 3C , the entire area of the character information shown in FIG. 3B is divided into four blocks and a left-upper most end point in each of the blocks has preferably a relative priority. The order of the blocks is preferably in the order of a block 1 , a block 2 , a block 3 , and a block 4 . Referring to FIG. 3C , the character information whose end point is detected visits the end points in the order of E 1 , E 2 , E 3 , and E 4 .
[0056] The character information correcting step S 220 includes a step S 222 in which the character information rotating unit 220 calculates a direction angle using one reference point among the end points and a step S 224 in which the character information rotating unit 220 rotates the character information using the calculated direction angle.
[0057] In the step S 222 of calculating the direction angle using the reference point, the character information rotating unit 220 calculates an angle of the reference point with respect to predetermined n directions using one of the end points as the reference point. The angle is preferably determined to minimize the angle formed by the eight directions of the center point of the character information and one reference point of end points. The reference point according to the exemplary embodiment is preferably an end point whose visiting order is the first. The center point is preferably an average position with respect to the positions of all points of the character information. As described in detail referring to FIG. 4 , the predetermined n directions are preferably eight directions where the center point P and a displacement when n is 8 form π/4. The direction angle is preferably calculated so as to be an angle θ of eight directions with respect to the center point p using the end point E 1 whose visiting order is the first as the reference point.
[0058] In the step S 224 of rotating the character information using the calculated direction angle, the character information rotating unit 220 rotates the input character information in a normalized form which is not inclined. The character information is preferably rotated so as to minimize the angle using the angle calculated in the step S 222 of calculating the direction angle. The direction that minimizes the angle is preferably a direction for a minimum angle among θ calculated in the step S 222 of calculating the direction angle. Referring to FIG. 4 , an angle θ formed by the direction 3 and the end point E 1 is a minimum angle and the direction 3 is a direction that minimizes the angle. Therefore, the entire character information is preferably rotated so that the end point E 1 of the character information corresponds to the direction 3 .
[0059] In the step S 300 of assigning the code into the normalized character information, the code assigning unit 300 assigns a chain code that indicates a heading direction of the stroke or a divergence point that indicates that the strokes cross to each other to the points configuring the character information normalized in the step S 200 of normalizing the character information. The heading direction of the stroke is preferably a relative position on a stroke of a subsequent point with respect to a feature point in the stroke included in the character information and points configuring the stroke. As described in detail referring to FIG. 6A , the chain code is preferably a code that represents the feature point of the stroke configuring the character information and the relative position information of a subsequent point on the stroke with numbers. Preferably, the check code represents the relative position of a subsequent point of a specific point C in one to eight directions. What the strokes cross to each other means that the strokes configuring the character information may share at least one point. The crossing of the strokes according to the exemplary embodiment means that the feature point included in the character information is diverged into at least three points. The divergence point is diverged with respect to the feature point. Referring to FIG. 7B , a divergence point B is preferably assigned to a point at which the strokes cross to each other.
[0060] The chain code or the divergence point is preferably assigned to visit each of points configuring the character information in the visiting order set for the detected end point. The visiting order will be described in detail with reference to FIG. 5 .
[0061] FIG. 5 is a flowchart illustrating a method that the code assigning unit 300 assigns a code or a point according to an exemplary embodiment of the present invention.
[0062] Referring to FIG. 5 , a method that the code assigning unit 300 assigns the code or the point according to the exemplary embodiment includes a step S 310 in which the code assigning unit 300 visits a starting point using one of the end points as the starting point, a step S 315 of visiting a subsequent point of the starting point, a step S 320 of checking whether the subsequent point is the end point, a step S 325 of checking the presence of the stored divergence position when the subsequent point is the end point, a step S 330 of returning to the divergence position when the stored divergence position is present, and a step S 315 of visiting a subsequent point which is not visited in the returned divergence position. The method further includes a step S 335 of checking whether the subsequent point is the divergence point when the subsequent point is not the end point, a step S 340 of storing the position of the divergence point when the subsequent point is the divergence point, a step S 345 of assigning the divergence point, a step S 315 of visiting a point subsequent to the divergence point, a step S 350 of assigning a chain code when the subsequent point is not the divergence point, and a step S 315 of visiting a subsequent point. When the stored divergence position is not present in the step S 325 of checking the presence of the stored divergence position, the visiting is completed.
[0063] According to the exemplary embodiment, in the step S 310 of visiting the starting point, the code assigning unit 300 preferably visits an end point whose visiting order is set to be the first in the step S 214 of setting the visiting order of the character information to which the end point is assigned. Referring to FIG. 3C , it is preferable to visit the end point E 1 whose visiting order is set to be the first as the starting point. In case of the character information in which the end point is not present, for example, in case of number 8, the left-upper most part of the character information is set to be an E 1 position.
[0064] In the step S 315 of visiting a point subsequent to the starting point, the code assigning unit 300 visits a subsequent point according to the predetermined visiting order. As the predetermined visiting order, a depth first search method that a point whose relative position is the left-upper most has a priority in accordance with the visiting order of the end point set in the step S 214 of setting the visiting order of the end point is used. According to the depth first search method, after visiting one peak point, a peak point which is next to the above peak point and has not been visited is selected to repeat the above sequences. According to the exemplary embodiment, a point next to the starting point is visited. However, if the starting point is the divergence point, a point whose relative position is the left-upper most is prioritized to be visited. Referring to FIG. 7B , the point whose relative position is the left-upper most is prioritized so as to visit the peak point (a peak point to which a chain code is set to 3) which is located at the left-upper most side among the peak points which have not been visited in the case of the peak point to which the divergence point B is assigned.
[0065] The step S 320 of checking whether the subsequent point is the end point is a step in which the code assigning unit 300 checks whether a point visited as a subsequent point is an end point. If the subsequent point is the end point, presence of the divergence position is confirmed in the step S 325 of checking the presence of the stored divergence position. If the subsequent point is not the end point, in the step of checking whether the subsequent point is the divergence point which will be described below, it is checked whether the subsequent point is the divergence point (S 335 ).
[0066] In the step S 335 of checking whether the subsequent point is the divergence point, if the point visited by the code assigning unit 300 is not the end point, it is checked whether the subsequent point is a divergence point which is diverged into three or more points. If the subsequent point is a divergence point, the code assigning unit 300 stores the divergence position (S 340 ), the divergence point is assigned to the visited point (S 345 ). If the subsequent point is not a divergence point, the code assigning unit 300 assigns a chain code (S 350 ) and then visits a subsequent point (S 315 ).
[0067] When the point visited by the code assigning unit 300 is the divergence point, the step S 340 of storing the divergence position preferably stores the divergence position in order to visit a second prioritized point among the above-mentioned priorities. According to the exemplary embodiment, the divergence position is preferably stored using a stack structure according to the LIFO (last in first out) manner.
[0068] As described above, the step S 345 of assigning the divergence point to the visited point preferably assigns the divergence point B to a point at which the strokes cross in FIG. 7B .
[0069] The step S 350 of assigning a chain code preferably assigns a numeral code of the chain code of FIG. 6A to each of points in FIG. 7A . The step S 350 of assigning a chain code includes a step S 355 of assigning a curved point.
[0070] In the step S 355 of assigning a curved point, the code assigning unit 300 preferably assigns the curved point to the visited point when an angle formed by a current heading direction of the stroke and a subsequent heading direction of the stroke with respect to the visited point is larger than a predetermined threshold value. Referring to FIG. 6C , when the difference between the current heading direction of the stroke and the subsequent heading direction of the stroke is 45 degree larger than a predetermined threshold value with respect to the currently visited point, the curved point is assigned to the visited point using a 5 by 5 sized mask shown in FIG. 6C . The current heading direction is the sixth direction according to the chain code shown in FIG. 6A , but the subsequent heading direction is the first direction. Therefore, since the angle difference between the heading directions is the same as the threshold value, the curved point C is preferably assigned to the visited point.
[0071] A smaller angle between angles formed by the previous heading direction of the stroke and the subsequent heading direction of the stroke is preferably compared with the threshold value. The smaller angle is preferably an angle 1 between an angle 1 and an angle 2 which are formed by the current heading direction and the subsequent heading direction in FIG. 6C .
[0072] In the step S 320 of checking whether the subsequent point is the end point, the code assigning unit 300 checks the presence of the stored divergence position when the subsequently visited point is the end point (S 325 ). In the step S 325 of checking the presence of the stored divergence position, the code assigning unit 300 checks the presence of the divergence position stored in the step S 340 of storing the divergence position. When the divergence position is present, the code assigning unit returns to the divergence position (S 330 ), and then visits a point which has not been visited with respect to the returned divergence position (S 315 ). In the step S 325 of checking the presence of the divergence position, if the stored divergence position is not present, it is determined that all points configuring the character information are visited and then the visiting is completed.
[0073] In the step S 330 of returning to the divergence position, the code assigning unit 300 returns to the divergence position in order to visit a point which has not been visited in the stored divergence position. The step S 315 of visiting the subsequent point visits a point which has not been visited using the divergence position returned in the step S 330 of returning to the divergence position as a new starting point according to the order of priority (S 315 ).
[0074] A step S 400 of sequencing a structural feature including an end point or a divergence point using a point which is assigned to the normalized character information will be described with reference to FIG. 9 .
[0075] FIG. 9 is a flowchart illustrating of a process of sequencing character information as a structural feature code by a sequencing unit 400 according to an exemplary embodiment of the present invention. The step S 400 of sequencing the structural feature according to the exemplary embodiment includes a step S 410 of generating a structural feature code, a step S 420 of generating a structural feature numeral string, a step S 430 of applying a weight for the structural feature to the generated numeral string, and a modeling step S 440 of generalizing the weighted numeral string with respect to the character information.
[0076] The structural feature point is preferably characteristics of a stroke including an end point, a curved point, and a divergence point of the character information. In the step S 410 of generating the structural feature code, the structural feature code generating unit 410 preferably generates a numeral code corresponding to a code or a point assigned to the structural feature point of the character information. The numeral code is preferably generated such that numeral information corresponding to the code or the point of the structural feature point is generated in accordance with a predetermined numeralization representing method. According to the exemplary embodiment, the predetermined numeralization representing method assigns a numeral code “0” to the end point to which the end point code E is set. Further, the divergence points to which the divergence code B is assigned are preferably assigned in accordance with the number of divergence positions, for example, 92 when the number of divergence positions is two, 93 when the number of divergence positions is three, and 94 when the number of divergence positions is four. A chain code value of the current heading direction and a chain code value of the subsequent heading direction are preferably assigned to the curved point. FIG. 8 shows a result that the end point of the character information is set to ‘0’, the divergence point is set to ‘93’, the curved point is set to ‘61’, as the structural feature code.
[0077] In the step S 420 of generating a structural feature numeral string, a numeral string generating unit 420 preferably sequences the numeral code which is assigned to the character information in accordance with the visiting order to generate the numeral string. Referring to FIG. 10 , the step S 420 of generating a structural feature numeral string preferably represents the character information using the numeral code generated in the step S 410 of generating the structural feature code and the chain code assigned in the step S 350 of assigning the chain code with the numeral strings in accordance with the above-mentioned visiting order.
[0078] In the step S 430 of applying a weight for the structural feature to the generated numeral string, the numeral string generating unit 420 preferably repeats the numeral code set for the structural feature point using a distance between the structural feature positions. The numeral string which is formed only by chain codes represents only direction information between adjacent two positions, so that the entire structure of a character is not reflected. The step S 430 of applying a weight for the structural feature to the generated numeral string defines an end point, a divergence point, and a curved point in addition to the chain code and the above points represent an important structure of a character. Therefore, it is preferable to repeatedly assign a numeral code using a weight, which is different from the chain code.
[0079] The weights of the structural feature points are preferably set by repeating the numeral codes of the structural feature points. In the exemplary embodiment, the weights preferably use the distance between the positions of the structural feature points. In other words, if there are eight chain codes between the end points and end point, each of the end points is set to be repeated four times. Alternatively, in the pattern of end point—eight chain codes—curved point—six chain codes—end point, generally, it is represented by five (one+four) end points—eight chain codes—eight (four+one+three) curved points—six chain codes—four (one+three) end points. Here, the number 1 refers to its own structural point. As described in detail with reference to FIG. 11 , the numeral code of the end point E 1 is repeatedly represented 3/2 times more, the numeral code of the end point E 2 is repeatedly represented 1/2 times more, the numeral code of the end point E 3 is repeatedly represented 1/2 times more, and the numeral code of the end point E 4 is repeatedly represented 1/2 times more. The repetition frequency is preferably rounded off. The curved points C are repeated 3/2 and 3/2 times more, respectively, and the divergence points B are repeated 3/2, 1/2, 1/2, and 1/2 times more. The final order string to which a weight is applied according to the exemplary embodiment is shown in FIG. 11 . In FIG. 11 , the bold numbers refer to the repeated numeral code according to the weight.
[0080] In the modeling step S 440 of generalizing the weighted numeral string with respect to the character information, if a numeral string of a character to be recognized is generated, a modeling unit 500 models at least 50 training data for numeral strings of character strings to be trained using a HMM (Hiden Markov Model) method. If a user wants to recognize a number according to the exemplary embodiment, 10 HMM models that are trained 50 times for every number of 0 to 9 are generated and a HMM based recognition device recognizes numbers through a corresponding model from an input character (number) image regardless of the length of the sequence string.
[0081] FIG. 12 is a block diagram illustrating a sequencing apparatus of character information according to an exemplary embodiment of the present invention. Referring to FIG. 12 , the sequencing apparatus 1 of the character information according to the exemplary embodiment includes a pre-processing unit 100 that receives and pre-processes a character image, a normalizing unit 200 that normalizes character information as character information according to a predetermined criteria, a code assigning unit 300 that assigns a chain code that indicates a heading direction of a stroke or a divergence point that indicates the crossing of the stroke to points configuring the character information, a sequencing unit 400 that sequences the character information to which the code or the point is assigned using structural features including an end point or a divergence point, a modeling unit 500 that generalizes a numeral string for the character information using the numeral string generated in the sequencing unit, and a database unit 600 that stores or manages the modeled numeral strings.
[0082] The pre-processing unit 100 , as described above, extracts character information from the image and binarizes the extracted character information through a predetermined threshold value and then extracts and thins a center line of the binarized character information (S 100 ).
[0083] The normalizing unit 200 includes an end code assigning unit 210 that detects an end point of a character stroke having one adjacent point among points configuring the pre-processed character information to assign an end point code and a character information rotating unit 220 that corrects an inclined angle of the character information in accordance with a predetermined angle using an end point to which an end point code is assigned.
[0084] The end point code assigning unit 210 detects the end point of the stroke included in the character information and assigns an end point code that indicates an end point to the detected end point (S 212 ) and sets a visiting order in accordance with a predetermined order of the end points to which the end points are assigned (S 214 ).
[0085] The character information rotating unit 220 calculates an angle formed by a reference point and predetermined n directions using one of end points as the reference point (S 222 ) and rotates the input character information with a non-inclined normalized format (S 224 ).
[0086] The code assigning unit 300 assigns a chain code that indicates a heading direction of a stroke, a divergence point that indicates the crossing of the stroke, or a curved point that indicates that the heading direction of the stroke is changed more than a predetermined threshold angle to each of the points configuring the normalized character information (S 300 ). The code assigning unit 300 assigns a code or a point to a visited point by visiting a subsequent point according to a predetermined visiting order. As the predetermined visiting order, a depth first search method that a point whose relative position is the left-upper most has a priority as described above is used.
[0087] The sequencing unit 400 includes a structural feature code generating unit 410 that generates a structural feature code and a numeral string generating unit 420 that generates a numeral string using the structural feature code and applies a weight for the structural feature to the generated numeral string.
[0088] The structural feature code generating unit 410 generates a numeral code corresponding to a code assigned to the structural feature point of the character information (S 410 ). The structural feature point is preferably characteristics of a stroke including an end point, a curved point, and a divergence point of the character information.
[0089] The numeral string generating unit 420 sequences the numeral code which is assigned to the character information in accordance with the visiting order to generate the numeral string (S 420 ) and defines an end point, a divergence point, and a curved point in addition to the chain code. Since the above points represent an important structure of a character, the numeral string generating unit 420 repeatedly assigns a numeral code using a weight, which is different from the chain code (S 430 ).
[0090] If a numeral string of a character to be recognized is generated, the modeling unit 500 models at least 50 training data for numeral strings of character strings to be trained using a HMM (Hiden Markov Model) method (S 440 ).
[0091] The database unit 600 stores and manages information of models for the character information modeled in the modeling unit 500 . Information on 10 HMM models that are trained 50 times for every number is stored and managed. The HMM based recognition device receives input character (number) image regardless of the length of the numeral string and recognizes the number through a corresponding model from models of the database unit 600 .
[0092] Further, a method that recognizes the pre-processed character information using the modeling information represented by a numeral string by applying a weight to a structural feature point including the end point, the divergence point, and the curved point of character information in accordance with a predetermined algorithm uses a trained modeled information trained by the algorithm according to an exemplary embodiment of the present invention to make the input character image as a numeral string according to the method of sequencing the character information according to the exemplary embodiment to recognize the character through the corresponding model.
[0093] The method of sequencing character information according to the exemplary embodiment of the present invention may be implemented in a computer readable recording medium as a computer readable code. The computer readable recording medium includes all kinds of recording devices in which data readable by a computer system is stored.
[0094] The embodiments according to the present invention may be implemented in the form of program instructions that can be executed by computers, and may be recorded in computer readable media. The computer readable media may include program instructions, a data file, a data structure, or a combination thereof. By way of example, and not limitation, computer readable media may comprise computer storage media and communication media. Computer storage media includes both volatile and nonvolatile, removable and non-removable media implemented in any method or technology for storage of information such as computer readable instructions, data structures, program modules or other data. Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, digital versatile disks (DVD) or other optical disk storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other medium which can be used to store the desired information and which can accessed by computer. Communication media typically embodies computer readable instructions, data structures, program modules or other data in a modulated data signal such as a carrier wave or other transport mechanism and includes any information delivery media. The term “modulated data signal” means a signal that has one or more of its characteristics set or changed in such a manner as to encode information in the signal. By way of example, and not limitation, communication media includes wired media such as a wired network or direct-wired connection, and wireless media such as acoustic, RF, infrared and other wireless media. Combinations of any of the above should also be included within the scope of computer readable media.
[0095] As described above, the exemplary embodiments have been described and illustrated in the drawings and the specification. The exemplary embodiments were chosen and described in order to explain certain principles of the invention and their practical application, to thereby enable others skilled in the art to make and utilize various exemplary embodiments of the present invention, as well as various alternatives and modifications thereof. As is evident from the foregoing description, certain aspects of the present invention are not limited by the particular details of the examples illustrated herein, and it is therefore contemplated that other modifications and applications, or equivalents thereof, will occur to those skilled in the art. Many changes, modifications, variations and other uses and applications of the present construction will, however, become apparent to those skilled in the art after considering the specification and the accompanying drawings. All such changes, modifications, variations and other uses and applications which do not depart from the spirit and scope of the invention are deemed to be covered by the invention which is limited only by the claims which follow. | Disclosed is a method of sequencing character information in order to increase precision of character recognition. The method includes: a pre-processing that extracts character information from an image to binarize the extracted character information through a predetermined threshold and extracts and thins a center line of the binarized character information; normalizing the pre-processed character information to character information according to a predetermined criteria; and sequencing the normalized character information using structural features including an end point or a divergence point of the character information. The present invention suggests an angle normalization method of input character information, a structural feature position determining method, and a structural feature numeral string generating method to strongly recognize characters configured by various fonts obtained from a natural scene regardless of an angle or a size of the characters. | 6 |
BACKGROUND OF THE INVENTION
The present invention relates to downhole fishing and drilling operations, or removing obstructions to a drilling line when such a line becomes lodged or otherwise stuck in a well bore. Consequences of failure to remove the obstruction can be failure of the well to produce at all or in part, also, current methods of removing obstructions can result in failure to loosen the work string, both of which result in having to relocate the drilling operation, which necessarily involves lost time and money.
This problem can be overcome, as it is now, by various devices which exert pressure or mechanical energy on the work string in an attempt to dislodge it. These tools are generally large, complex and expensive, and many are not easily configured to apply varying amounts of force to the work string, which can result in imprecise application of energy to the work string. This, in turn, can break or otherwise damage the work string, resulting in a requisite move of a project, or at the very least, lost time and energy in repairing the work string.
The current invention fills the existing gap in technology by providing a relatively small, simple, adjustable tool which can be easily transported and implemented and be tailored to specific applications.
It is known in the art to apply force to dislodge a work string, however the current devices in this field do not offer the unique combination of the small, simple and configurable characteristics inherent in the configuration presented herein.
OBJECTS OF THE INVENTION
One object of this invention is to provide a configurable device which can apply specific amounts of pressure to a work string.
Another object of the invention is to provide a device that is small and easily transported.
Still another object of the invention is to provide a device that is able to shield an adjustment mechanism with a sleeve.
Other objects and advantages of this invention shall become apparent from the ensuing descriptions of the invention.
SUMMARY OF THE INVENTION
According to the present invention, the invention is a downhole tool for manipulating a work string which is easily configured to deliver a specific amount of force to the work string in a small and simple apparatus.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings illustrate an embodiment of this invention. However, it is to be understood that this embodiment is intended to be neither exhaustive, nor limiting of the invention. They are but examples of some of the forms in which the invention may be practiced.
FIG. 1A shows a side view of the top half of the jarring tool, partially disassembled.
FIG. 1B shows a side view of the bottom half of the jarring tool, partially disassembled.
FIG. 2A shows a cutaway view of the top half of the jarring tool.
FIG. 2B shows a cutaway view of the bottom half of the jarring tool.
FIG. 3 shows a top view of the aligning collar.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
Without any intent to limit the scope of this invention, reference is made to the figures in describing the various embodiments of the invention. Referring to FIGS. 1 through 3 , line downhole jarring tool 100 is pictured.
Jarring tool 100 has a hammer mandrel 101 near the top end of jarring tool 100 which is formed with shaft 113 extending from the bottom end of hammer mandrel 101 . Shaft 113 can be formed such that a portion of shaft 113 has beveled sides, providing a flat surface that permits the shaft to be turned with a wrench, as well as forming a “keyed” relationship with the square opening 122 of retaining mandrel 102 's aligning collar 121 . This “keyed” relationship prevents relational torquing between shaft 113 and retaining mandrel 102 . This arrangement also precludes the need for aligning screws or other components, which detract from the simplicity and effectiveness of a tool.
At the end of shaft 113 , shaft 113 forms a releasable bolt 103 which can be shaped conically as pictured, but could conceivably take various shapes, so long as releasable bolt 103 could be grasped and retained by another device, as explained in further detail below. The conical or “spear” shape of releasable bolt 103 also facilitates the re-entry of releasable bolt 103 into collet 105 , explained in greater detail below.
Retaining mandrel 102 surrounds shaft 113 , and is usually threaded at one end to receive firing mandrel 104 which lies below it on jarring tool 100 . Firing mandrel 104 is generally cylindrical in shape, and having unlatching recess 117 along firing mandrel's 104 inner diameter, which is shaped to accommodate collet 105 as outlined below. Releasable bolt 103 also prevents shaft 113 from disengaging retaining mandrel 102 by virtue of releasable bolt's 103 size being larger than that of the edge 116 of retaining mandrel 102 .
Collet 105 is attached to a kinetic energy shaft 118 toward the top end of jarring tool 100 . Collet 105 can have longitudinal slits 114 around its body, such that the overall diameter of collet 105 can be permitted to increase by radially expanding or separating slits 114 . The top end 115 of collet 105 should also be configured to be of larger diameter than the remainder of collet 105 to create a section that can enter either latching recess 117 or unlatching recess 123 of firing mandrel 104 permitting collet 105 to expand. This will be explained in greater detail below.
Positioned between collet 105 and middle joint 107 is reloading mechanism 106 , generally a spring or spring-type device, which is held in place between collet 105 and middle joint 107 . It is positioned such that pressure is exerted upwardly on collet 105 and downwardly on middle joint 107 .
Kinetic energy store 109 is positioned around kinetic energy shaft 118 , and can be any mechanical kinetic energy store, like a Belleville washer stack or a spring. Kinetic energy store 109 is usually a Belleville washer stack, which is generally an assemblage of concave washers stacked end to end such that resistance and linear energy is built up when the kinetic energy store 109 is compressed.
At the base of kinetic energy shaft 118 is threaded or otherwise attached adjuster collar 110 . This is configured such that as adjuster collar 110 is threaded onto the bottom end of kinetic energy shaft 118 , such that as adjuster collar 110 is turned up the tool, compression is naturally increased on the kinetic energy store 109 , and thus upward resistance is increased.
There is also in some exemplary forms of the invention threaded hole 119 drilled in kinetic energy shaft 118 , generally perpendicular to the lateral axis of jarring tool 100 . This provides for setscrew 120 which, when engaged in threaded hole 119 , prevents adjuster collar 110 from turning about its axis.
Surrounding and encasing kinetic energy shaft 118 and kinetic energy store 109 is bottom mandrel 112 . Integrated in bottom mandrel 112 is adjuster collar guard 108 . Collar guard 108 has opening 111 which is essentially a window used to access adjuster collar 110 . Collar guard 108 is able to be turned about the axis of the tool, such that opening 111 only reveals a small portion of the surface beneath it. When properly actuated, however, opening 111 of collar guard 108 reveals adjuster collar 110 so that it may be accessed, and thus adjusted via various means. If collar guard 108 is then turned further, it effectively conceals adjuster collar 108 , thus preventing contaminants from entering, or from accidental adjustment of the components.
Joining bottom mandrel 112 to firing mandrel 104 is middle joint 107 , which also houses a portion of kinetic energy shaft 118 .
Each of the parts which lie along the central axis, if they are to be used in an application which requires electrical, data or other connections at the base of the tool can have a bore drilled parallel to this axis to permit runs of electrical or other wire through the center of jarring tool 100 . In such an application, parts along the center portion of the tool, such as shaft 113 , releasable bolt 103 , hammer mandrel 101 , collet 105 and kinetic energy shaft 118 have a bore in the center of them, permitting a wire or other ductile compound to be threaded through them, and thus, the entire tool.
In operation, line downhole jarring tool 100 will be attached on its top and bottom ends to the work string. Jarring tool 100 will be likely initially “set,” whereby releasable bolt 103 is inserted into the center of collet 105 . This “setting” procedure is accomplished by moving shaft 113 , and thus bolt 103 , toward the bottom end of jarring tool 100 . Bolt will press against collet 105 , pushing it down whereby the top 115 of collet 105 will enter latching recess 117 , and bolt 103 will enter collet 105 . In this way, bolt 103 becomes mechanically coupled with collet 105 , and is ready for the impact stroke of jarring tool 100 .
Adjuster collar guard 108 will be rotated about the axis of jarring tool 100 so that opening 111 will permit access to setscrew 120 , such that setscrew 120 may be removed, in turn permitting adjuster collar 110 to be threaded up or down, providing a corresponding increase or decrease in the tension stored in kinetic energy store 109 . In an exemplary embodiment, each full turn of adjuster collar 110 will raise or lower the pressure stored in kinetic energy store 109 by one hundred (100) pounds. Setscrew 120 can then be replaced, effectively locking adjuster collar 110 in place. Adjuster collar guard 108 can then be rotated back around to re-conceal setscrew 120 and related parts of adjuster collar 110 . Naturally, the setting need not be one hundred pounds, but is helpful to the operator to be in whole number increments, as to provide easy administration of pressure changes.
When an obstruction is encountered, or the drill string otherwise needs to be loosened, force will be applied to jarring tool 100 , drawing back on the end of jarring tool 100 . When this force is applied to hammer mandrel 101 , shaft 113 is also drawn upward by virtue of its mechanical connection to hammer mandrel 101 . Releasable bolt 103 will similarly be drawn back, and move with it collet 105 and thus kinetic energy shaft 118 .
As the force is applied, kinetic energy will continue to build as a result of the compression of kinetic energy store 109 under the force applied to hammer mandrel 101 . As this force increases, hammer mandrel 101 , shaft 113 , releasable bolt 103 , collet 105 , and kinetic energy shaft 118 all move toward the top end of jarring tool 100 until collet's 105 top end 115 slides into unlatching recess 117 , at which point longitudinal slits 114 expand, and releasable bolt 103 is released.
As a result of this, the full store of kinetic energy in kinetic energy store 109 is exerted up and away, such that releasable bolt 103 travels quickly up within retaining mandrel 102 until it strikes edge 116 of retaining mandrel 102 , delivering the upward stroke, which, by design, helps to loosen the work string.
At this time, the previous force exerted upon tool should be reversed, mechanically or otherwise, such that releasable bolt 103 will be inserted back into collet 105 . As bolt 103 is inserted into collet 105 , collet 105 is pushed back beyond unlatching recess 117 such that slits 114 are compressed, once again holding and retaining releasable bolt 103 within the confines of collet 105 . This cycle is thus repeated to achieve the desired hammering effect to loosen or otherwise manipulate the work string.
Although only a few exemplary embodiments of this invention have been described in detail above, those skilled in the art will readily appreciate that many modifications are possible in the exemplary embodiments without materially departing from the novel teachings and advantages of this invention. Accordingly, all such modifications are intended to be included within the scope of this invention as defined in the following claims. | A downhole jarring apparatus including a shaft and a first mandrel configured to releasably engage, a collar operatively attached to the shaft such that an axial position of the collar relative to the shaft is adjustable by access through an opening in an outer surface of a second mandrel, and an energy store configured to exert a force against the shaft, wherein the force is adjustable in response to the axial position of the collar relative to the shaft. | 4 |
BACKGROUND OF THE INVENTION
[0001] For a variety of reasons there are occasions when tubular structures such as casings and production tubing, for example, positioned downhole in wellbores need to be cut. Some examples are for removal of a damaged section of tubing or to provide a window for diagonal drilling.
[0002] Cutters have been developed that have rotating portions with knives that are pivoted radially outwardly to engage the inner surface of the tubular structure to perform a cut. Such cutters have a multitude of pivoting joints, cams and actuators that interact to rotate the knives between the noncutting and cutting configurations. The complexity of such cutters increases fabrication costs and potential failure modes.
[0003] Accordingly, the art is in need of less complex cutting tools.
BRIEF DESCRIPTION OF THE INVENTION
[0004] Disclosed herein relates to a single piece tubular member. The tubular member having a non-radially displaceable portion and a radially displaceable portion, the radially displaceable portion being movable to a position of similar radial displacement as that of the non-radially displaceable portion and a position of relatively large radial displacement in comparison to the non-radially displaceable portion. The tubular member also having at least one cutting arrangement disposed at the radially displaceable portion.
[0005] Further disclosed herein relates to a cutting tool. The cutting tool having a deformable tubular member having an inside surface and an outside surface and a plurality of lines of weakness thereat. At least one of the lines of weakness being positioned closer to one of the outside surface and the inside surface and at least one other of the plurality of lines of weakness being positioned closer to the other of the outside surface and the inside surface. The cutting tool also having at least one cutting element disposed at a portion of the tubular member most radially displaceable from an undeformed position of the tubular member.
[0006] Further disclosed herein relates to a method of cutting a downhole tubular. The method includes delivering a tubular cutting tool, with a plurality of lines of weakness thereon, to a downhole position within a downhole tubular that is to be cut, rotating the tubular cutting tool, and actuating the tubular cutting tool. The actuating causing a radially deformable portion of the tubular cutting tool to radially deform compared to an unactuated position of the tubular cutting tool. The actuating also causing a cutting element attached to the radially deformable portion to contact a downhole tubular to be cut.
[0007] Further disclosed herein relates to a method for making a cutting tool. The method includes configuring a deformable tubular member with a plurality of lines of weakness, with at least one of the plurality of lines of weakness disposed at each of an inside dimension and an outside dimension of the tubular member. The method also includes locating the plurality of lines of weakness relative to each other to facilitate deforming a portion of the tubular member to a greater radial dimension than the undeformed tubular member, and locating a cutting arrangement on the portion.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] The following descriptions should not be considered limiting in any way. With reference to the accompanying drawings, like elements are numbered alike:
[0009] FIG. 1 depicts a partial cross sectional view of a cutting tool disclosed herein in an unactuated configuration;
[0010] FIG. 2 depicts a partial cross sectional view of the cutting tool of FIG. 1 in an actuated configuration;
[0011] FIG. 3 depicts a partial cross sectional view of the cutting tool of FIG. 2 taken at arrows 3 - 3 ;
[0012] FIG. 4 depicts a partial cross sectional view of another embodiment of a cutting tool disclosed herein in an unactuated configuration;
[0013] FIG. 5 depicts a partial cross sectional view of the cutting tool of FIG. 4 in an actuated configuration; and
[0014] FIG. 6 depicts a partial cross sectional view of the cutting tool of FIG. 5 taken at arrows 6 - 6 .
DETAILED DESCRIPTION OF THE INVENTION
[0015] A detailed description of several embodiments of the disclosed apparatus and method are presented herein by way of exemplification and not limitation with reference to the Figures.
[0016] Referring to FIGS. 1 and 2 , a partial cross sectional view of an embodiment of the cutting tool 10 is illustrated. The cutting tool 10 includes a tubular member 14 that has a radially displaceable portion 18 and a non-radially displaceable portion 20 . As illustrated in FIG. 1 the radially displaceable portion 18 is in an unactuated configuration and as illustrated in FIG. 2 the radially displaceable portion 18 is in an actuated configuration. In the actuated configuration the radially displaceable portion 18 forms two frustoconical sections 22 and 26 . The greatest radial deformation 30 of the tubular member 14 occurs where the two frustoconical sections 22 and 26 meet. Thus, an annular flow area 34 is defined by the greatest radial deformation 30 and an outside surface 38 of the non-radially displaceable portion 20 . At least one axial groove 42 in the outside surface 38 forms a first fluid passage through which fluid can flow between an uphole annular area 44 and a downhole annular area 46 when the radially displaceable portion 18 is in the actuated configuration. A second fluid passage 50 is formed through the center of the tubular member 14 defined by an inside surface 52 of the tubular member 14 .
[0017] The greatest radial deformation 30 contacts an inner surface 60 of a tubular structure 62 that is to be cut by the cutting tool 10 . A cutting arrangement positioned at the greatest radial deformation 30 engages with and cuts through the tubular structure 62 . The cutting arrangement can include a hardened portion of the metal of which the tubular member 14 is made, which can include sharpened portions of the metal, for example. Alternately the cutting arrangement can include an insert of another material into the tubular member 14 . A cutting arrangement insert can be made of such materials as tungsten carbide or diamonds, for example, which can be used separately or in combination.
[0018] The radially displaceable portion 18 is reconfigurable between the unactuated configuration and the actuated configuration. In the unactuated configuration the frustoconical sections 22 and 26 are configured as cylindrical components having roughly the same inside dimension as the tubular member 14 in the uphole annular area 44 and a downhole annular area 46 . Reconfiguration from the unactuated to the actuated configuration is effected, in one embodiment, by the application of an axial compressive load on the tubular member 14 . Conversely, reconfiguration from the actuated to the unactuated configuration is effected by the application of an axial tensile load on the tubular member 14 .
[0019] Reconfigurability of the radially displaceable portion 18 between the actuated configuration and the unactuated configuration is due to the construction thereof. The radially displaceable portion 18 is formed from a section of the tubular member 14 that has three lines of weakness, specifically located both axially of the tubular member 14 and with respect to the inside surface 52 and the outside surface 38 of the tubular member 14 . In one embodiment, a first line of weakness 66 and a second line of weakness 70 are defined in this embodiment by diametrical grooves formed in the outside surface 38 of the tubular member 14 . A third line of weakness 74 is defined in this embodiment by a diametrical groove formed in the inside surface 52 of the tubular member 14 . The three lines of weakness 66 , 70 and 74 each encourage local deformation of the tubular member 14 in a radial direction that tends to cause the groove to close. It will be appreciated that in embodiments where the line of weakness is defined by other than a groove, the radial direction of movement will be the same but since there is no groove, there is no “close of the groove”. Rather, in such an embodiment, the material that defines a line of weakness will flow or otherwise allow radial movement in the direction indicated. The three lines of weakness 66 , 70 and 74 together encourage deformation of the tubular member 14 in a manner that creates a feature such as the radially displaceable portion 18 . The feature is created, then, upon the application of an axially directed mechanical compression of the tubular member 14 such that the radially displaceable portion 18 is actuated as the tubular member 14 is compressed to a shorter overall length. Other mechanisms can alternatively be employed to actuate the tubular member 14 between the unactuated relatively cylindrical configuration and the actuated configuration presenting the frustoconical sections 22 and 26 . For example, the tubular member 14 may be reconfigured to the actuated configuration by diametrically pressurizing the tubular member 14 about the inside surface 52 in the radially displaceable portion 18 .
[0020] Referring to FIG. 3 , a cross sectional view of the cutting tool 10 of FIG. 2 is shown taken at arrows 3 - 3 . The fluid passages between the cutting tool 10 and the inside surface 52 , of the tubular structure 60 , created by the axial grooves 42 , is illustrated. Although the axial grooves 42 are illustrated herein as V-shaped, it should be appreciated that alternate embodiments can have grooves of any shape. It should also be noted that in alternate embodiments the cutting tool 10 could be used to cut through any downhole tubular structure such as a casing 78 for example.
[0021] Referring to FIGS. 4 and 5 , an alternate exemplary embodiment of the cutting tool 110 is illustrated. The cutting tool 110 includes a tubular member 114 and a radially displaceable portion 118 . The radially displaceable portion 118 includes a plurality of extension members 120 attached thereto. As illustrated in FIG. 4 the radially displaceable portion 118 is in an unactuated configuration and as illustrated in FIG. 5 the radially displaceable portion 118 is in all actuated configuration. In the actuated configuration the radially displaceable portion 118 forms two frustoconical sections 122 and 126 . The extension members 120 are fixedly attached to the first frustoconical section 122 at a first portion 128 . A second portion 129 of the extension members 120 is positioned radially outwardly of the second frustoconical section 126 but is not attached to the second frustoconical section 126 . As such when the radially displaceable portion 118 is actuated the extension members 120 remain substantially parallel to the first frustoconical section 122 causing the second portion 129 of the extension members 120 to extend radially outwardly of the outermost portion of the frustoconical members 122 , 126 . As such the greatest radial deformation 130 of the cutting tool 110 occurs at an end 132 of each of the extension members 120 . Control of the relationship of the greatest radial deformation 130 to the radial dimension of the end 132 in the unactuated configuration is completely controllable by setting the lengths of the second portions 129 . An annular flow area 134 is defined by the greatest radial deformation 130 and an outside surface 138 of a non-radially displaceable portion 140 . At least one axial space 142 between adjacent extension members 120 forms a first fluid passage through which fluid can flow between an uphole annular area 144 and a downhole annular area 146 when the centralizer 110 is in the actuated configuration. A second fluid passage 150 is formed through the center of the tubular member 114 defined by the inside surface 162 in the outside surface 138 forms a first fluid passage through which fluid can flow between an uphole annular area 144 and a downhole annular area 146 when the radially displaceable portion 118 is in the actuated configuration. A second fluid passage 150 is formed through the center of the tubular member 114 defined by an inside surface 152 of the tubular member 114 .
[0022] The greatest radial deformation 130 contacts an inner surface 60 of a tubular structure 62 that is to be cut by the cutting tool 110 . A cutting arrangement positioned at the greatest radial deformation 130 of the extension members 120 engages with and cuts through the tubular stricture 62 . The cutting arrangement can include a hardened portion of the metal from which the extension members 120 are made. Alternately the cutting arrangement can include an insert of another material into the extension members 120 . A cutting arrangement insert can be made of such materials as tungsten carbide or diamonds, for example, which can be used separately or in combination.
[0023] The radially displaceable portion 118 is reconfigurable between the unactuated configuration and the actuated configuration. In the unactuated configuration the frustoconical sections 122 and 126 are configured as cylindrical components having roughly the same inside dimension as the tubular member 114 in the uphole annular area 144 and a downhole annular area 146 . Reconfiguration from the unactuated to the actuated configuration is effected, in one embodiment, by the application of an axial compressive load on the tubular member 114 . Conversely, reconfiguration from the actuated to the unactuated configuration is effected by the application of an axial tensile load on the tubular member 114 .
[0024] Reconfigurability of the radially displaceable portion 118 between the actuated configuration and the unactuated configuration is due to the construction thereof. The radially displaceable portion 118 is formed from a section of the tubular member 114 that has three lines of weakness, specifically located both axially of the tubular member 114 and with respect to the inside surface 152 and the outside surface 138 of the tubular member 114 . In one embodiment, a first line of weakness 166 and a second line of weakness 170 are defined in this embodiment by diametrical grooves formed in the outside surface 138 of the tubular member 114 . A third line of weakness 174 is defined in this embodiment by a diametrical groove formed in the inside surface 152 of the tubular member 114 . The three lines of weakness 166 , 170 and 174 each encourage local deformation of the tubular member 114 in a radial direction that tends to cause the groove to close. It will be appreciated that in embodiments where the line of weakness is defined by other than a groove, the radial direction of movement will be the same but since there is no groove, there is no “close of the groove”. Rather, in such an embodiment, the material that defines a line of weakness will flow or otherwise allow radial movement in the direction indicated. The three lines of weakness 166 , 170 and 174 together encourage deformation of the tubular member 114 in a manner that creates a feature such as the radially displaceable portion 118 . The feature is created, then, upon the application of an axially directed mechanical compression of the tubular member 114 such that the radially displaceable portion 118 is actuated as the tubular member 114 is compressed to a shorter overall length. Other mechanisms can alternatively be employed to actuate the tubular member 114 between the unactuated relatively cylindrical configuration and the actuated configuration presenting the frustoconical sections 122 and 126 . For example, the tubular member may be reconfigured to the actuated configuration by diametrically pressurizing the tubular member 114 about the inside surface 152 in the radially displaceable portion 118 .
[0025] Referring to FIG. 6 , a cross sectional view of the cutting tool 110 of FIG. 5 is shown taken at arrows 6 - 6 . The fluid passages between the cutting tool 110 and the inside surface 60 , of the tubular structure 62 , created by the axial spaces 142 between the extension members 120 , is illustrated. Although the extension members 120 depicted herein are rectangular prisms, it should be noted that alternate embodiments could have extension members of any shape. It should also be noted that in alternate embodiments the cutting tool 110 could be used to cut through any downhole tubular structure such as a casing 78 for example.
[0026] While the invention has been described with reference to an exemplary embodiment or embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the claims. | Disclosed herein relates to a single piece tubular member. The tubular member having a non-radially displaceable portion and a radially displaceable portion, the radially displaceable portion being movable to a position of similar radial displacement as that of the non-radially displaceable portion and a position of relatively large radial displacement in comparison to the non-radially displaceable portion. The tubular member also having at least one cutting arrangement disposed at the radially displaceable portion. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to the field of data processing and more particularly to central processing units.
2. Brief Description of the Prior Art
Sparse vectors are multi-operand vectors having zero or near zero operands removed and the remaining operands packed together. An apparatus for processing such vectors by a computer's central processing unit is disclosed in U.S. Pat. No. 3,919,534 to Hutson, et al. Such apparatus forwards operands to the arithmetic logic unit (ALU) from a given sparse vector one at a time. Zero operands are provided to the ALU only when a second sparse vector being input to the ALU for coprocessing has a non-zero operand in that order. An order vector is provided for each sparse vector to indicate by the state of a bit whether the correspondingly ordered sparse vector operand is zero or non-zero.
SUMMARY OF THE INVENTION
The present invention converts sparse vector format into unpacked format and forwards n-operands at a time to an n-wide arithmetic logic unit for tandem processing. In this manner, overall processing speed may be increased up to n times.
Unpacking is performed by inspecting the corresponding order vector n bits at a time. Operands are taken from the head of the sparse vector and positioned for each one-bit in the order vector. Zeros or a preselected operand value are inserted for each zero-bit in the order vector. A one-bit population count is performed on the n-bit segment of the order vector to control the moving of the sparse vector operands forward according to the count.
Selectively substituting all one-bits for the order vector at predetermined points in the logic allows the apparatus to expand a sparse vector into an expanded vector and/or compress a vector into a sparse vector.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a schematic of a circuit to expand a sparse vector for tandem procession by an ALU; and
FIG. 2 shows a schematic of a circuit to compress tandem resultants from an ALU into a sparse vector.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 shows a schematic of the apparatus for unpacking a sparse vector for subsequent processing by an arithmetic logic unit (ALU). Normally, the ALU will coprocess two vectors at a time: adding, subtracting, multiplying or dividing them. The apparatus shown in FIG. 1 unpacks only one such vector. For processing two vectors, the apparatus of FIG. 1 is duplicated.
A typical vector has a number of operands in a specific order such as A 0 , A 1 , A 2 , A 3 . . . , A n . A sparse vector is a vector having certain predetermined operand values deleted. Normally, operands having a value of 0 or near 0 are deleted. The remaining operands are concatenated or packed for more efficient storage in memory and retrieval therefrom. For example, assume operands A 2 , A 3 and A 8 of a given vector have the value of zero. That vector's sparse vector would appear in memory as A 1 , A 4 , A 5 , A 6 , A 7 , A 9 , . . . to A n .
When performing an arithmetic operation with vectors, the corresponding order of operands of each vector must normally be simultaneously input to the ALU for processing. For example, when adding vector A to vector B, the corresponding order operands must be added, e.g., A 1 +B 1 , A 2 +B 2 , A 3 +B 3 , . . . A n +B n .
As the sparse vectors located in memory do not have any inherent alignment information, i.e., the counting of five operands in from the first operand does not indicate operand A 4 , each sparse vector must be provided with a corresponding order vector. An order vector consists essentially of a series of bits, one bit for each operand of a normal unpacked vector. The state of the bit is either zero or one. Zero indicates that the correspondingly ordered operand of the vector is deleted. One indicates that the correspondingly ordered operand of the vector is present. Only those operands corresponding to the one-bits, therefore, will be actually stored in memory.
In the prior art, such as with U.S. Pat. No. 3,919,534 to Hutson, et al., the order vector was inspected essentially one bit at a time. When a one-bit was encountered, the operand first in line was forwarded to the ALU for processing. But when a zero bit was encountered, an operand was not forwarded. With two vectors being simultaneously coprocessed, a one-bit in either order vector caused the forwarding of at least the operand from the sparse vector in which the order vector had a one-bit. If the other order vector had a zero-bit, a zero valued operand was inserted and forwarded instead of the operand at the head of the line.
The apparatus of FIG. 1 modifies this procedure by inspecting a group of eight order bits at a time. (In this regard, eight is an arbitrary number. The actual number of bits inspected can be arbitrarily chosen as may be appreciated by those skilled in the art.) Operands of a preselected value, such as zero are inserted into the operand stream coming from memory according to the occurrence of zeros in the order vector. The resulting expanded or unpacked eight operands are forwarded in parallel to the ALU for simultaneous tandem processing. An ALU such as found in the CDC CYBER 205 has the capability of processing eight operands in tandem.
If every bit of the order vector is a one signifying that eight non-zero operands are to be forwarded to the ALU, an increase in speed of up to eight times is achieved over the prior art method of forwarding one operand at a time to the ALU.
Sparse vector operands are fetched from memory by apparatus not shown and forwarded through interconnected eight-operand registers R1, R2 and R3, respectively, such that operands A 0 through A 7 (assuming in this example that the sparse vector has no zero valued operands) are located in R3, A 8 to A 15 in R2 and A 16 to A 23 in R1.
As the sparse vector operands are being loaded into registers R1 through R3, the sparse vector's corresponding order vector is loaded eight bits at a time into register X0. Each machine cycle, eight more bits are loaded into register X0 until all order vector bits have been loaded. Likewise, each machine cycle the contents of register X0 are copied by interconnected register X2 and also are provided as an input to a one-bit population counter EP1. The results of the population count, which may range from a count of 0 to a count of 8, are loaded into a four bit register X1 during the same machine cycle.
On the third machine cycle, the contents of register X2 are loaded into interconnected register X3. The four-bit count of register X1 is provided as one input to adder A1. The other input to adder A1 is provided by three bits from register SC1, which is initialized to a starting shift count determined by a programmer. A bias of 0 is provided as the fourth bit to this adder input. The three-bit output of adder A1 is loaded into three-bit register SC1 during the machine cycle. Also, a carry bit is loaded into carry register C1. The three-bit limitation on the adder's output provides that any addition having a result higher than the number seven has a carry input to carry register C1. The lower order three bits of a resultant are input to register SC1. Also during this machine cycle, interconnected register SC2 copies the contents of register SC1.
At the end of three machine cycles, register X3 contains the first group of eight bits of the order vector; SC1 has the three bit count of the number of 1 bits in that first group of order-vector bits plus the starting shift count, and register SC2 contains the starting shift count.
On the fourth machine cycle, the eight bits of register X3 are provided as inputs to expansion network E1. Also provided as inputs are eight outputs of shift network 10. The shift network receives fifteen operands: eight from register R3 and seven from R2. It shifts these operands to its eight outputs according to the count in register SC2, which on the fourth machine cycle contains the starting shift count. The expansion network E1 also receives preset data operands, normally a value of zero, from the preset data line. The expansion network arranges the two sets of operand inputs according to the arrangement of order vector bits contained in register X3.
For example, assume the starting shift count is zero and the initial eight bits of the order vector are 10011011, the leftmost list corresponding to A 0 . Register R3 then contains in its lowest ordered cells sparse vector operands as follows:
A.sub.0, A.sub.3, A.sub.4, A.sub.6, A.sub.7
R3.sub.0, R3.sub.1, R3.sub.2, R3.sub.3, R3.sub.4.
The expansion network E1 inspects the lowest order bit from the order vector bits in X3 and, finding it to be a one, places operand A 0 from register R3 on its lowest order output. It inspects the next highest order bit from register X3 and, finding it to be a zero, places a preset data operand (0) on the second lowest order output, and so on, until the expansion network's eight outputs are as follows:
A.sub.0, O, O, A.sub.3, A.sub.4, O, A.sub.6, A.sub.7.
These eight outputs are simultaneously provided as inputs to the ALU for tandem processing.
During the next machine cycle, the fifth, the contents of register SC1, which is the count of the number of one-bits in the first group of eight order-vector bits, is loaded into register SC2. The output of register SC2 causes the shift network 10 to point to R3 cell address 5 for our example in which the number of one-bits in the first group of order-vector bits is five. By "point to", it is meant that the shift network shifts R3 cells 5, 6, and 7, and R2 cells 0, 1, 2, 3 and 4 into its eight outputs.
The second group of eight order bits is copied during this same machine cycle into register X3. Assuming the second group of order vector bits contains the following pattern: 01011101, the operands present in the shift network outputs (in part) will have originated from the fifth order R3 cell to the second order R2 cell as follows:
A.sub.9, A.sub.11, A.sub.12, A.sub.13, A.sub.15
R3.sub.5, R3.sub.6, R3.sub.7, R2.sub.0, R2.sub.1.
The expansion network E1 places these five operands on its outputs according to the pattern of order vector bits in register X3: 01011101. Thus the E1 outputs at the end of the fifth cycle will be O,A 9 ,O,A 11 ,A 12 ,A 13 ,O,A 15 . These eight operands are forwarded in parallel for tandem coprocessing by the ALU.
The contents of SC1 in the previous machine cycle, cycle number four, was the number five reflective of five one-bits present in the first group of order vector bits. In addition to this count being loaded into SC2 for control of shift network 10, it is also fed back as the second input to adder A1, as explained supra. The second group of order-vector bits also had five one-bits. Thus the population counter EP1 will have forwarded a count of five to the first input to adder A1. The addition of these two count-of-five inputs causes the adder to place on its output the number 2 with a carry. The three lower most order bits have a bit-pattern 010 and are forwarded to the register SC1. The carry is forwarded to carry register C1.
During the fifth machine cycle, the presence of a 1 bit in the carry register causes register R3 to copy the contents of register R2, register R2 to copy the contents of register R1 and register R1 to load a new group of eight sparse vector operands.
Assuming the third and fourth groups of order vector bits are all ones, the contents of register R3 and R2, after this move, will appear as follows:
A.sub.13, A.sub.15, A.sub.16 . . . A.sub.29
R3.sub.0, R3.sub.1, R3.sub.2, . . . R2.sub.7.
During this same machine cycle the contents of register SC1, 010, is loaded into register SC2. During the next machine cycle shift network 10 will thus point to R3 2 , the second lowest order cell of register R3, which correctly contains the next sparse vector operand to be processed, A 16 .
The process continues as such until each operand of the sparse vector has been forwarded to the ALU.
With more particularity, if the order vector inputs to expansion network E1 are denoted by Z 0 , Z 1 . . . Z n , the eight operand inputs from shift network 10 denoted by A, A 1 , . . . A n , the expansion network's outputs denoted by O 0 , O 1 , . . . O n , and B=preset data, the following logic equations describe the operation of expansion network E1.
______________________________________ C.sub.00 = A.sub.0.sup.--Z.sub.0 + A.sub.1 Z.sub. 0 C.sub.10 = A.sub.1.sup.--Z.sub.0 + A.sub.2 Z.sub. 0 C.sub.20 = A.sub.2.sup.--Z.sub.0 + A.sub.3 Z.sub. 0 C.sub.30 = A.sub.3.sup.--Z.sub.0 + A.sub.4 Z.sub. 0 C.sub.40 = A.sub.4.sup.--Z.sub.0 + A.sub.5 Z.sub. 0 C.sub.50 = A.sub.5.sup.--Z.sub.0 + A.sub.6 Z.sub. 0 C.sub.60 = A.sub.6.sup.--Z.sub.0 + A.sub.7 Z.sub. 0 C.sub.01 = C.sub.00.sup.--Z.sub.1 + C.sub.10 Z.sub. 1 C.sub.11 = C.sub.10.sup.-- Z.sub.1 + C.sub.20 Z.sub. 1 C.sub.21 = C.sub.20.sup.--Z.sub.1 + C.sub.30 Z.sub. 1 C.sub.31 = C.sub.30.sup.--Z.sub.1 + C.sub.40 Z.sub. 1 C.sub.41 = C.sub.40.sup.--Z.sub.1 + C.sub.50 Z.sub. 1 C.sub.51 = C.sub.50.sup.--Z.sub.1 + C.sub.60 Z.sub. 1 C.sub.02 = C.sub.01.sup.--Z.sub.2 + C.sub.11 Z.sub. 2 C.sub.12 = C.sub.11.sup.--Z.sub.2 + C.sub.21 Z.sub. 2 C.sub.22 = C.sub.21.sup.--Z.sub.2 + C.sub.31 Z.sub. 2 C.sub.32 = C.sub.31.sup.--Z.sub.2 + C.sub.41 Z.sub. 2 C.sub.42 = C.sub.41.sup.--Z.sub.2 + C.sub.51 Z.sub. 2 C.sub.03 = C.sub.02.sup.--Z.sub.3 + C.sub.12 Z.sub. 3 C.sub.13 = C.sub.12.sup.--Z.sub.3 + C.sub.22 Z.sub. 3 C.sub.23 = C.sub.22.sup.--Z.sub.3 + C.sub.32 Z.sub. 3 C.sub.33 = C.sub.32.sup.--Z.sub.3 + C.sub.42 Z.sub. 3 C.sub.04 = C.sub.03.sup.--Z.sub.4 + C.sub.13 Z.sub. 4 C.sub.14 = C.sub.13.sup.--Z.sub.4 + C.sub.23 Z.sub. 4 C.sub.24 = C.sub.23.sup.--Z.sub.4 + C.sub.33 Z.sub. 4 C.sub.05 = C.sub.04.sup.--Z.sub.5 + C.sub.14 Z.sub. 5 C.sub.15 = C.sub.14.sup.--Z.sub.5 + C.sub.24 Z.sub. 5 C.sub.06 = C.sub.05.sup.--Z.sub.6 + C.sub.15 Z.sub. 6 O.sub.0 = B.sup.--Z.sub.0 + A.sub.0 Z.sub. 0 O.sub.1 = B.sup.--Z.sub.1 + C.sub.00 Z.sub. 1 O.sub.2 = B.sup.--Z.sub.2 + C.sub.01 Z.sub. 2 O.sub.3 = B.sup.--Z.sub.3 + C.sub.02 Z.sub. 3 O.sub.4 = B.sup.--Z.sub.4 + C.sub.03 Z.sub. 4 O.sub.5 = B.sup.--Z.sub.5 + C.sub.04 Z.sub. 5 O.sub.6 = B.sup.--Z.sub.6 + C.sub.05 Z.sub. 6 O.sub.7 = B.sup.--Z.sub.7 + C.sub.06 Z.sub. 7______________________________________
It will be recognized by those skilled in the art that the above logic equations may best be implemented bit by bit on the respective operands A and B.
The ALU receives the operands n pairs at a time and performs n arithmetic or logic operations thereon in tandem. After having performed these functions, the ALU outputs n resultants per machine cycle. Some of those resultants may have a value of zero or an invalid result in the case of a divide by zero. It is desirable to store these resultants in memory with the zero or invalid resultants deleted. The apparatus for performing such deletions is illustrated in FIG. 2.
Each machine cycle operands from a first expanded vector are stored in n-operand register R4. Likewise operands from a second expanded vector are stored in n-operand register R24. The ALU loads the operands from these registers, performs n tandem logical or arithmetic operations thereon and stores the n resultants in n-resultant register R5. These n resultants are then compressed into sparse vector format during the next machine cycle by compress network CR1, which will be hereinafter more fully described. The compressed resultants are stored in register R6. The number of resultants stored in R6 depends on the number of valid resultants (zero or invalid resultants deleted) present in the group of n resultants. These resultants are then forwarded to memory via downstream apparatus not shown.
The determination of which resultants are valid and which are zero or invalid is made according to a logical combination of the order vectors for the two sparse vectors, one of which is labeled the X order vector and the other of which is labeled the Y order vector. For example, if the operation to be performed on the two sparse vectors is an add or a subtract operation, the resultant vector will have a valid resultant for a given order whenever one of the input vectors had a valid operand in that order. If order vector X comprises 10000110 and order vector Y comprises 01001010, a resultant order vector Z will appear 11001110, a one corresponding to a valid resultant. This Z order vector is the logical "OR" of the X and Y order vectors. Likewise, if the operation is a multiply or a divide, the resultant order vector Z would appear 00000010, which is the logical "AND" of the X and Y order vector. Similar logical manipulation may be performed on the X and Y order vector to find a resultant order vector for any logical or arithmetic operation performed by the ALU.
In FIG. 2, this logical operation is performed in block SDO, which has as inputs the two operand order vectors X and Y, as well as an indication of the function or op-code to be performed by the ALU. Block SDO receives the two order vectors, eight bits each machine cycle, and stores the results in register X10.
Register X10 through X13 are delay registers which delay the resultant order vector Z the number of machine cycles as the input sparse vector operands need to pass through registers R1, R2, R3 and R4.
The output from register X13 is stored in register X14. But, as the transfer between these two registers occurs during the same period of time the operands are being processed by the ALU, the transfer is delayed by functional unit delay 20 to synchronize the arrival of Z order vector bits in X14 with the arrival of resultants in register R5. The time of the delay depends upon the logical or arithmetic operation being performed by the ALU.
The contents of register X14 are provided as one input to compress network CR1. They are also provided as the input to population counter CP1, which counts the number of one bits therein. This count, representative of the number of valid operands in R5, is forwarded to four-bit register X15. Register X15's output is provided to downstream circuitry to indicate the number of valid sparse vector resultants that are available in register R6 for storage in memory.
The operation of compress network CR1 is illustrated by the following example. Assuming the resultant order vector Z from register R14 comprises the bit pattern 10101101, the resultants present in register R5, r 0 , r 1 , r 2 . . . r 8 will be compressed and stored, left justified, into register R6 as follows: r 0 , r 2 , r 4 , r 5 , r 7 , 0, 0, 0. r 1 , r 3 and r 6 , which correspond to zeroes in the Z order vector, have been deleted.
The logic equations for compress network CR1, where Z 0 through Z 7 represent resultant order vector bits input from register X14, A 0 , A 1 , A 2 , . . . A 7 represent resultants input from register R5 and r 0 , r 1 , r 2 . . . r 7 represent the output of compress network CR1, comprise the following:
______________________________________ C.sub.70 = A.sub.7 Z.sub.7 C.sub.60 = A.sub.6 Z.sub.6 C.sub.50 = A.sub.5 Z.sub.5 C.sub.40 = A.sub.4 Z.sub.4 C.sub.30 = A.sub.3 Z.sub.3 C.sub.20 = A.sub.2 Z.sub.2 C.sub.10 = A.sub.1 Z.sub.1 C.sub.00 = A.sub.0 Z.sub.0 C.sub.71 = C.sub.70 Z.sub.6 C.sub.61 = C.sub.70.sup.--Z.sub.6 + C.sub. 60 C.sub.72 = C.sub.71 Z.sub.5 C.sub.62 = C.sub.71.sup.--Z.sub.5 + C.sub.61 Z.sub. 5 C.sub.52 = C.sub.61.sup.--Z.sub.5 + C.sub. 50 C.sub.73 = C.sub.72 Z.sub.4 C.sub.63 = C.sub.72.sup.--Z.sub.4 + C.sub.62 Z.sub. 4 C.sub.53 = C.sub. 62.sup.--Z.sub.4 + C.sub.52 Z.sub. 4 C.sub.43 = C.sub.52.sup.--Z.sub.4 + C.sub. 40 C.sub.74 = C.sub.73 Z.sub.3 C.sub.64 = C.sub.73.sup.--Z.sub.3 + C.sub.63 Z.sub. 3 C.sub.54 = C.sub.63.sup.--Z.sub.3 + C.sub.53 Z.sub. 3 C.sub.44 = C.sub.53.sup.--Z.sub.3 + C.sub.43 Z.sub. 3 C.sub.34 = C.sub.43.sup.--Z.sub.3 + C.sub. 30 C.sub.75 = C.sub.74 Z.sub.2 C.sub.65 = C.sub.74.sup.--Z.sub.2 + C.sub.64 Z.sub. 2 C.sub.55 = C.sub.64.sup.--Z.sub.2 + C.sub.54 Z.sub. 2 C.sub.45 = C.sub.54.sup.-- Z.sub.2 + C.sub.44 Z.sub. 2 C.sub.35 = C.sub.44.sup.--Z.sub.2 + C.sub.34 Z.sub. 2 C.sub.25 = C.sub.34.sup.--Z.sub.2 + C.sub. 20 C.sub.76 = C.sub.75 Z.sub.1 C.sub.66 = C.sub.75.sup.--Z.sub.1 + C.sub.65 Z.sub. 1 C.sub.56 = C.sub.65.sup.--Z.sub.1 + C.sub.55 Z.sub. 1 C.sub.46 = C.sub.55.sup.--Z.sub.1 + C.sub.45 Z.sub. 1 C.sub.36 = C.sub.45.sup.--Z.sub.1 + C.sub.35 Z.sub. 1 C.sub.26 = C.sub.35.sup.--Z.sub.1 + C.sub.25 Z.sub. 1 C.sub.16 = C.sub.25.sup.--Z.sub.1 + C.sub. 10 r.sub.7 = C.sub.77 = C.sub.76 Z.sub.0 r.sub.6 = C.sub.67 = C.sub.76.sup.--Z.sub.0 + C.sub.66 Z.sub. 0 r.sub.5 = C.sub.57 = C.sub.66.sup.--Z.sub.0 + C.sub.56 Z.sub. 0 r.sub.4 = C.sub.47 = C.sub.56.sup.--Z.sub.0 + C.sub.46 Z.sub. 0 r.sub.3 = C.sub.37 = C.sub.46.sup.--Z.sub.0 + C.sub.36 Z.sub. 0 r.sub.2 = C.sub.27 = C.sub.36.sup.--Z.sub.0 + C.sub.26 Z.sub. 0 r.sub.1 = C.sub.17 = C.sub.26.sup.--Z.sub.0 + C.sub.16 Z.sub. 0 r.sub.0 = C.sub.07 = C.sub.16.sup. --Z.sub.0 + C.sub.______________________________________ 00
The above sets of equations imply the use of two-way OR's. The preferred embodiment actually uses four-way OR's. Those skilled in the art should modify the above equations when implementing the logic with four-way OR's to produce equivalent four-way OR logic.
While not illustrated, those skilled in the art will appreciate that a substitution of one-bits for the Z order vector bits will result in every resultant in register R5 being transferred undisturbed to register R6 and thence to memory. The resultant vector stored in memory under these circumstances would be in the expanded, uncompressed format. These one-bits may conveniently be introduced at register X10. If only one sparse vector is introduced and the ALU op-code is a NO-OP, the net result is that a sparse vector is converted to an expanded vector.
Likewise, if the vector or vectors in memory to be processed by the ALU are already in their expanded format (and maybe not even possessing an order vector), a group of one-bits input to register X 0 of FIG. 1 in lieu of the order vector bits results in no expansion in network EP1. In this manner, an expanded vector or vectors may be processed and compressed. If only one is input and the ALU op-code is a NO-OP, the net result is that the expanded vector is compressed into a sparse vector.
If one bits are substituted at both X0 and X10, one or more expanded vectors may be processed by the disclosed apparatus.
Other similar modifications are likely to occur to those skilled in the art. | Apparatus is disclosed for processing sparse vectors in a tandem or parallel processing environment. Sparce vectors are those vectors stored in memory with their zero-valued operands deleted. They have a corresponding order vector of bits whose state indicates the order of zero and non zero operands in a corresponding expanded vector. The apparatus fetches the order vectors n bits at a time, n corresponding to the number of tandem processors, and counts the number of one bits. This number of operands is then fetched from memory. The apparatus aligns and orders the fetched sparse vector operands, inserts zero operands where appropriate, and forwards the resulting portion of the expanded vector to the tandem processors for processing. | 7 |
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] NOT APPLICABLE
STATEMENT AS TO RIGHTS TO INVENTIONS MADE UNDER FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] NOT APPLICABLE
REFERENCE TO A “SEQUENCE LISTING,” A TABLE, OR A COMPUTER PROGRAM LISTING APPENDIX SUBMITTED ON A COMPACT DISK
[0003] NOT APPLICABLE
BACKGROUND OF THE INVENTION
[0004] 1. Field of the Invention
[0005] The present invention is related generally to the field of orthodontics. More particularly, the present invention is related to methods and systems for dispensing a series of orthodontic appliances in a sequence to a patient.
[0006] Repositioning teeth for aesthetic or other reasons is accomplished conventionally by wearing what are commonly referred to as “braces.” Braces comprise a variety of appliances such as brackets, archwires, ligatures, and O-rings. Attaching the appliances to a patient's teeth is a tedious and time consuming enterprise requiring many meetings with the treating orthodontist. Consequently, conventional orthodontic treatment limits an orthodontist's patient capacity and makes orthodontic treatment quite expensive. Moreover, from the patient's perspective, the use of braces is unsightly, uncomfortable, presents a risk of infection, and makes brushing, flossing, and other dental hygiene procedures difficult.
[0007] As a result, alternative methods and systems for repositioning teeth have been developed. For example, repositioning may be accomplished with a system comprising a series of appliances configured to receive the teeth in a cavity and incrementally reposition individual teeth in a series of at least three successive steps. Most often, the methods and systems reposition teeth in from ten to twenty-five successive steps, although complex cases involving many of the patient's teeth may take forty or more steps. The individual appliances are typically comprised of a polymeric shell having the teeth-receiving cavity formed therein, typically by molding. The successive use of a number of such appliances permits each appliance to be configured to move individual teeth in small increments.
[0008] Typically the systems are planned and all individual appliances are fabricated at the outset of treatment. Thus, the appliances may be provided to the patient as a single package or system. The order in which the appliances are to be used can be marked by sequential numbering directly on the appliances or on tags, pouches or other items which are affixed to or which enclose each appliance so that the patient can place the appliances over his or her teeth in an order and at a frequency prescribed by the orthodontist or other treating professional. Successive appliances will be replaced when the teeth either approach (within a preselected tolerance) or have reached the target end arrangement for that stage of treatment, typically being replaced at an interval in the range from 2 days to 20 days, usually at an interval in the range from 5 days to 10 days.
[0009] In general, it is preferable to simplify procedures for the patient to increase patient compliance and reduce patient errors in carrying out the treatment protocol. Therefore, it is desirable to utilize a packaging or ordering system which will provide appliances to a patient in a manner which is clearly discernable to the patient the order of the appliances. In addition, such packaging or ordering system should be amenable to mid-treatment changes to the treatment protocol, possibly adding or eliminating appliances after the initial set of appliances has been produced and packaged. At least some of these objectives will be met by the methods and systems of the present invention described hereinafter.
[0010] 2. Description of the Background Art
[0011] Tooth positioners for finishing orthodontic treatment are described by Kesling in the Am. J. Orthod. Oral. Surg. 31:297-304 (1945) and 32:285-293 (1946). The use of silicone positioners for the comprehensive orthodontic realignment of a patient's teeth is described in Warunek et al. (1989) J. Clin. Orthod. 23:694-700. Clear plastic retainers for finishing and maintaining tooth positions are commercially available from R AINTREE E ssix , I NC ., New Orleans, La. 70125, and T RU -T AIN P LASTICS , Rochester, Minn. 55902. The manufacture of orthodontic positioners is described in U.S. Pat. Nos. 5,186,623; 5,059,118; 5,055,039; 5,035,613; 4,856,991; 4,798,534; and 4,755,139.
[0012] Other publications describing the fabrication and use of dental positioners include Kleemann and Janssen (1996) J. Clin. Orthodon. 30:673-680; Cureton (1996) J. Clin. Orthodon. 30:390-395; Chiappone (1980) J. Clin. Orthodon. 14:121-133; Shilliday (1971) Am. J. Orthodontics 59:596-599; Wells (1970) Am. J. Orthodontics 58:351-366; and Cottingham (1969) Am. J. Orthodontics 55:23-31.
BRIEF SUMMARY OF THE INVENTION
[0013] The present invention provides systems and methods for providing dental appliances, particularly orthodontic appliances, to a patient wherein the patient is easily able to determine the order or sequence in which the appliances should be worn. Typically the appliances are to be worn in a particular sequence to provide desired treatment, such as a progressive movement of teeth through a variety of arrangements to a final desired arrangement.
[0014] In a first aspect of the present invention, a system of dental appliances is provided comprising a plurality of dental appliances wherein at least some of the plurality include a non-numeric indicia designating an order in which each of the at least some of the plurality are to be worn by a patient to provide dental treatment. Typically, each of the plurality of dental appliances comprise a polymeric shell having cavities shaped to receive and resiliently reposition teeth from one arrangement to a successive arrangement. Exemplary embodiments of such dental appliances are described in U.S. Pat. No. 5,975,893, incorporated herein by reference for all purposes. In some embodiments, each of the polymeric shells has at least one terminal tooth cavity and the indicia comprises a terminal tooth cavity of differing length in each of the polymeric shells. In other embodiments, each of the polymeric shell has a height and the indicia comprises a different height in each of the polymeric shells.
[0015] In still other embodiments, the indicia comprises one or more cutouts so that each polymeric shell has a different cutout pattern. Sometimes the cutout comprises a notch in an edge of the appliance.
[0016] In yet other embodiments, the indicia comprises a color wherein each appliance has different color. The color of the appliances may have the same hue and vary by intensity, for example. The color may comprise a dissolvable dye. Or, the system may further comprise a wrapper removably attachable to each of the appliances, wherein each wrapper has the color.
[0017] In another aspect of the present invention, a system of packaged dental appliances is provided comprising a plurality of packages each containing a dental appliance, wherein the plurality of packages are joined in a continuous chain designating an order in which each of the dental appliances are to be worn by a patient to provide dental treatment. In some instances, the packages are each joined by a perforation wherein the packages can be separated by breaking the perforation. In other instances, the packages are joined by, for example, a heat seal. Further, the system may include a marking on a package at an end of the chain indicating the dental appliance to be worn first. Again, each of the plurality of dental appliances may comprise a polymeric shell having cavities shaped to receive and resiliently reposition teeth from one arrangement to a successive arrangement.
[0018] In a further aspect of the present invention, a system of dental appliances is provided comprising a plurality of dental appliances to be worn by a patient to provide dental treatment, and a framework, wherein each of the plurality of dental appliances are removably attached to a portion of the framework. In some embodiments, each of the plurality of dental appliances comprise a polymeric shell having cavities shaped to receive and resiliently reposition teeth from one arrangement to a successive arrangement. Further, the system may comprise at least one marking on the framework indicating the order in which the appliances are to be worn by a patient.
[0019] In still another aspect of the present invention, method of dispensing dental appliances to a patient is provided. The method including the step of providing a plurality of packages wherein each of the packages includes a polymeric shell having cavities shaped to receive and resiliently reposition teeth from one arrangement to a successive arrangement, the plurality of package including a first package containing a first shell to be worn by the patient to reposition the teeth from the one arrangement to the successive arrangement and a second package containing a second shell to be worn by the patient to reposition the teeth from the successive arrangement to another successive arrangement. The method further including the steps of delivering the first package to the patient at a designated time through a remote delivery system, and delivering the second package to the patient at a later designated time through the remote delivery system. In most embodiments, the remote delivery system comprises a mail delivery system.
[0020] In another aspect of the present invention, a method is provided of dispensing dental appliances to a patient including providing a dispenser including a plurality of dental appliances, wherein each of the appliances comprises a polymeric shell having cavities shaped to receive and resiliently reposition teeth from one arrangement to a successive arrangement, the plurality of appliances including a first shell to be worn by the patient to reposition the teeth from the one arrangement to the successive arrangement and a second shell to be worn by the patient to reposition the teeth from the successive arrangement to another successive arrangement, and removing the first shell from the dispenser wherein removal of the first shell dispenses the second shell.
[0021] In a further aspect of the present invention, a method of dispensing dental appliances to a patient is provided including providing a dispenser including a plurality of dental appliances, wherein each of the appliances comprises a polymeric shell having cavities shaped to receive and resiliently reposition teeth from one arrangement to a successive arrangement, the plurality of appliances including a first shell to be worn by the patient to reposition the teeth from the one arrangement to the successive arrangement and a second shell to be worn by the patient to reposition the teeth from the successive arrangement to another successive arrangement. The method further includes removing the first shell from the dispenser, and actuating an actuator that subsequently dispenses the second shell. In most embodiments, the actuator comprises a lever, knob, or button.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] FIG. 1 is a schematic illustration of a series of appliances dispensed in a chain.
[0023] FIG. 2 illustrates a series of appliances disposed on a framework.
[0024] FIG. 3 illustrates a series of appliances provided to a patient in a dispenser.
[0025] FIGS. 4A-4B illustrate a change in length of a terminal tooth cavity between appliances in a series.
[0026] FIGS. 5A-5B illustrate a change in height between appliances in a series.
[0027] FIGS. 6A-6B illustrate the addition of cutouts in each appliance to indicate an order.
[0028] FIGS. 7A-7C illustrate a change in color to indicate an order.
[0029] FIG. 8 illustrate an embodiment of a method of delivering appliances in a desired order.
[0030] FIG. 9 illustrates an appliance which includes a readable element embedded in the appliance.
[0031] FIG. 10 illustrates a series of packages 12 , each having a label which includes at least one non-numeric indicia.
[0032] FIG. 11 illustrates a package of dental appliances of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0033] It may be appreciated that the orthodontic appliances may be dispensed to the patient in its entirety, in groups or individually. Providing the patient with the entire series at the outset of treatment may be desirable if the treatment plan is relatively short, the patient is particularly compliant, or it is particularly convenient, to name a few. In this case, the series should be ordered so that the patient can easily selected the next appliance in the sequence when needed. Such ordering may be designated through packaging or the appliance itself. In some situations, the patient may receive additional appliances during the treatment protocol for inclusion in the sequence and/or the patient may receive instructions to eliminate some of the original appliances from the treatment protocol. Therefore, such ordering should allow easy incorporation of additional appliances or deletion of appliances.
[0034] Alternatively, the patient may be provided with a subset of the entire series, such as the first ten appliances. In this case, the subset should be ordered so that the patient can easily selected the next appliance in the sequence when needed. Again, such ordering may be designated through packaging or the appliance itself. The patient may receive additional appliances during the use of the subset for inclusion in the sequence and/or the patient may receive instructions to eliminate some of the original appliances from the subset. Alternatively, the next subset of appliances may differ from that which was initial determined at the outset of the treatment protocol. Therefore, such ordering should allow easy incorporation of additional appliances or deletion of appliances within or between subsets.
[0035] Further, the patient may be provided with individual appliances in the order in which they should be used. In this case, the appliances should be ordered so that the patient can easily differentiate the appliance they are receiving from the appliances already received. Again, such ordering may be designated through packaging or the appliance itself. In addition, such ordering should allow the appliances to be stored and distributed to the patient in the correct sequence with minimal attention from the orthodontic practitioner.
[0036] A variety of embodiments of ordering systems and methods will be described. In a first embodiment, a series of appliances are dispensed to the patient in a continuous chain, wherein the appliances are to be used in the sequence of the chain. An example of such a chain is schematically illustrated in FIG. 1 . Here, each appliance 10 is disposed within a package 12 , wherein the packages 12 are joined together in a continuous chain. In this embodiment, each package 12 is separable at a perforation 14 from the remaining packages 12 in the chain. It may be appreciated that the packages may be joined and/or are separable in any suitable manner including with the use of adhesives, heat sealing, ultrasonic welding, linkages or simply indications where to cut, break or separate, to name a few. To indicate the end of the chain in which it begin use, a marking may be located on the package 12 or on the appliance 10 . For example, a colored marking 16 may be located on an end package 12 a , as shown. This would indicate that a first appliance 10 a is enclosed. Once the first appliance 10 a has been removed from the package 12 a and worn for a given amount of time, the patient may then open a next package 12 b in the chain and remove a second appliance 10 b for wearing. This may be repeated throughout the chain.
[0037] In another embodiment, illustrated in FIG. 2 , a series of appliances 10 are disposed on a framework 20 , such as a sprue. Sprues typically secure objects, such as molded objects, before their first use. The appliances 10 are secured to the framework 20 in any suitable manner. The appliances 10 are then removed from the framework 20 according to a the treatment protocol. For example, the first appliance 10 a to be used may be disposed at one end of the framework 20 , the second appliance 10 b disposed next to the first appliance 10 a , the sequence continuing along the framework 20 . Alternatively or in addition, markings may be disposed on the framework 20 or the appliances 10 themselves indicating an ordering of use.
[0038] In another embodiment, illustrated in FIG. 3 , a series of appliances 10 are provided to a patient in a dispenser 30 . The dispenser 30 dispenses the appliances 10 in the order to be used. Each appliance 10 may be individually dispensed, as shown, or each appliance 10 may be contained in a package wherein the packages are individually dispensed. The dispenser 30 may include an actuator 32 , such as a lever, button, switch, etc, so that actuation of the actuator 32 dispenses the appliance 10 or package containing the appliance 10 . Alternatively, removal of an appliance 10 from the dispenser 30 may actuate dispensing of the next appliance 10 . In this way, the patient is systematically dispensed appliances in a predetermined order of use.
[0039] In some situations it may be desired to specifically mark the appliances themselves. Such markings ensure that ordering of the appliances is distinguishable after removal of the appliances from any packaging and during use. For example, a portion of each appliance may be changed to indicate a sequence or order. FIGS. 4A-4B illustrate a change in length of the appliance 10 by changing the length of a terminal tooth cavity 40 . A terminal tooth cavity 40 is one of the last teeth in the appliance. FIG. 4A illustrates a first appliance 10 a wherein a marked terminal tooth cavity 40 a has a given length. FIG. 4B illustrates a second appliance 10 b wherein a marked terminal tooth cavity 40 b has a length which differs from the first appliance 10 a . Here, the marked terminal tooth cavity 40 b has a shorter length. The lengths can continue to differ throughout the sequence of appliances. Alternatively or in addition, the lengths of other terminal teeth may differ.
[0040] FIGS. 5A-5B illustrate a change in the height of each appliance 10 to indicate a sequence or order. The height of the appliance 10 is the distance from the occlusal surfaces 46 to the edges 48 of the appliance 10 . FIG. 5A illustrates a first appliance 10 a having a given height. FIG. 5B illustrates a second appliance 10 b having a height which differs from the first appliance 10 a . Here, the second appliance 10 b has a shorter height. The heights can continue to differ throughout the sequence of appliances indicating an order. It may be appreciate that the overall height of the appliance may differ or the height of specific portions of the appliance may differ through the sequence.
[0041] FIGS. 6A-6B illustrate the addition of notches or cutouts 56 in each appliance 10 to indicate a sequence or order. The cut outs may be of any size, shape, orientation, or number forming any pattern. Further, the cut outs may be located on an edge 48 of the appliance 10 or on any surface, including an occlusal surface 46 . FIG. 6A illustrates a first appliance 10 a having a first cut out 56 a . The first cut out 56 a has a rectangular shape and is located near an edge 48 . FIG. 5B illustrates a second appliance 10 b having a second cut out 56 b so that the cut out pattern of the first appliance 10 a differs from that of the second appliance 10 b . Here, the second cut out 56 b also has a rectangular shape and is located near the edge 48 adjacent to the first cut out 56 a . The cut out patterns can continue to differ throughout the sequence of appliances indicating an order.
[0042] FIGS. 7A-7C illustrate a change in color, such as a hue, gradation of hues, shade, tint or intensity, for each appliance 10 to indicate a sequence or order. For example, the appliances 10 may appear darker or lighter in color through the series, such as ranging from dark red to light pink or vice versa. Or, the sequence may follow the color of the rainbow, such as red, orange, yellow, green, etc. Or, the sequence may follow any other prescribed order of colors. FIG. 7A illustrates a first appliance 10 a having a first color 60 a . FIG. 7B illustrates a second appliance 10 b having a second color 60 b so that the color of the first appliance 10 a differs from that of the second appliance 10 b . The color changes can continue to differ throughout the sequence of appliances indicating an order. It may be appreciated that the appliances 10 a , 10 b may have the color over their entirety, as shown, or the appliances may be colored in some areas and not in others. Or multiple colors may be used on a single appliance, such as in stripes, blocks or various shapes. The color may be embedded in the appliance, such as with the use of a colored plastic rather than the typical clear plastic. Or, the color may be in the form of a dissolvable dye which dissolves in contact with air, such as upon removal from a package, or contact with liquid, such as when rinsed with water or placed in the patient's mouth. Alternatively, as illustrated in FIG. 7C , the color may be present in a peel-away wrapper 62 . The colored wrapper 62 may be attached to the appliance 10 by lamination or other methods. In this example, the wrapper 62 covers the occlusal surfaces 46 of the appliance 10 , however any portion of the appliance 10 may be covered. When the appliance 10 is to be used, the wrapper 62 is peeled away, as shown, and removed. In this way, the appliances may be ordered by color but worn in a transparent state.
[0043] Alternatively or in addition, the patient may be provided with individual appliances in the order in which they should be used. To provide such ordering while allowing the appliances to be stored and distributed to the patient in the correct sequence with minimal attention from the orthodontic practitioner, a method may be used in which the appliances are delivered by mail in a specific sequence. FIG. 8 illustrates an embodiment of such a method. As shown, the appliances 10 are individually packaged so that a first package 80 contains a first appliance, a second package 82 contains a second appliance, a third package 84 contains a third appliance, etc. The packages 80 , 82 , 84 are sent through the mail or any delivery system so that they are delivered to the patient P according to a desired schedule. For example, the first package 80 is delivered to the patient P at day 1, the second package 82 is delivered at day 7, the third package 84 is delivered at day 14, etc. It may be appreciated that the individual packages may alternatively be comprises of series of appliances, such as subsets of the entire series of the treatment plan. In such a case, the patient P is delivered a package of appliances 10 at each interval, wherein each package includes a series of appliances. The series may itself also be ordered by any given system, including any of those mentioned above.
[0044] FIG. 9 illustrates one appliance 10 of a series of appliances wherein the appliance 10 includes a readable element 100 embedded in the appliance 10 . Alternatively, the readable element 100 may be affixed to the appliance 10 or to a package enclosing the appliance. The readable element 100 may comprise a chip, a bar code or other element that is computer readable, including identification by wireless means, including radiofrequency (rf) identification. When a reader 102 passes over the element 100 , the reader 102 translates the information into a word, symbol or other identifying feature. When translated into a word, the word may include, “first”, “second”, “third”, or “last” to name a few. Also, the word may be in any language, including English, Spanish, French, German, Japanese, etc. The word or identifying feature may be auditory, such as a recording or generation of a spoken voice, or visual, such as a print display. Alternatively, the feature may be transmitted by tactile means, such as by vibration.
[0045] FIG. 10 illustrates a series of packages 12 , each package 12 including at least one appliance 10 . Affixed to or incorporated in each package 12 is a label 100 . The label 100 includes at least one non-numeric indicia. For example, a first package 102 shows a label 100 having a series of numbers wherein one number is marked, in this case stamped with a colored dot 103 . This indicates which appliance 10 the first package 102 contains in the treatment sequence. It may be appreciated that the number can be marked with any symbol by any method, including removing the number by erasure, punch-out or notching. It may also be appreciated that other symbols may be used other than numbers, wherein one of the symbols is marked. This is illustrated in a second package 104 which shows such a label 100 . A third package 106 shows a label 100 having a series of symbols, such as shapes, in this case, trianglesl 20 . The symbols themselves or the color, number, or arrangement may indicate which appliance 10 the third package 106 contains in the treatment series. It may be appreciated that such symbols may include stripes, as illustrated on a fourth package 108 which shows such a label 100 . The stripes may be human readable or computer readable, such as a barcode.
[0046] FIG. 11 illustrates an embodiment of a package of dental appliances comprising a package 12 including a plurality of dental appliances 10 positioned in an arrangement within the package 12 which indicates an order of usage. In this embodiment, the arrangement comprises stacking of the appliances.
[0047] Although the foregoing invention has been described in some detail by way of illustration and example, for purposes of clarity of understanding, it will be obvious that various alternatives, modifications and equivalents may be used and the above description should not be taken as limiting in scope of the invention which is defined by the appended claims. | The present invention provides systems and methods for providing dental appliances, particularly orthodontic appliances, to a patient wherein the patient is easily able to determine the order or sequence in which the appliances should be worn. Typically the appliances are to be worn in a particular sequence to provide desired treatment, such as a progressive movement of teeth through a variety of arrangements to a final desired arrangement. | 0 |
TECHNICAL FIELD
This invention relates to a composition comprising a fluoroaliphatic radical-containing agent and a polymer comprising cyclic carboxylic anhydride groups for imparting water and oil repellency to fibrous substrates and other materials treated therewith. In another aspect, this invention relates to a method of using such composition to treat such substrates and materials, and in another aspect it relates to the so-treated substrates and materials.
BACKGROUND
The treatment of fibrous substrates with fluorochemical compositions to impart water and oil repellency is known; see, for example, Banks, Ed., Organofluorine Chemicals and Their Industrial Applications, Ellis Horwood Ltd., Chichester, England, 1979, pp. 226-234. Such fluorochemical compositions include, for example, fluorochemical guanidines (U.S. Pat. No. 4,540,497), compositions of cationic and non-ionic fluorochemicals (U.S. Pat. No. 4,566,981), compositions containing fluorochemical carboxylic acid and epoxidic cationic resin (U.S. Pat. No. 4,426,466), and fluoroaliphatic alcohols (U.S. Pat. No. 4,468,527).
Additives have been employed to assist in the oil and water repellency of fluorochemical treating agents.
U.S. Pat. No. 4,215,205 discloses combinations of fluorochemical vinyl polymer and carbodiimide in compositions said to impart durable water and oil repellency to textiles. Some of the carbodiimides disclosed contain fluoroaliphatic groups.
U.S. Pat. No. 5,132,028 discloses compositions for imparting water and oil repellency to fabrics such as silk, said compositions containing a fluorochemical-type, water and oil repellent agent, a carbodiimide, and at least one component selected from the group consisting of plasticizer, metal alcoholate or ester, zirconium salt, alkylketene dimer, aziridine, and alkenyl succinic anhydride.
U.S. Pat. No. 3,955,027 discloses an improved process and composition for water and oil proofing textiles which comprises treating a textile with a polymeric fluorocarbon finishing agent and at least one reactive polymer extender having acid or anhydride functionality and curing the treated textile at from 80° C. to 170° C. for 0.1 to 60 min. The reactive polymer extenders are low molecular weight polymers having a molecular weight of less than about 8000.
U.S. Pat. No. 4,070,152 discloses compositions comprising a textile treating resin which is a fluorine-containing polymer and a novel copolymer of a maleic-anhydride copolymer and a fatty acid amine and an amino organo polysiloxane. Said compositions are useful for increasing the water and oil repellency of substrates such as textiles, paper, or leather.
WO 93/01348 discloses aqueous treating compositions for providing water and oil repellency, stain resistance and dry soil resistance which comprise
a) 0.3 to 30% by weight of a water soluble or dispensable fluoroaliphatic radical-containing polyoxyalkylene compound;
b) 0.3 to 30% by weight of an anti-soiling agent, and
c) water. The anti-soiling agent may include i.e., styrene-maleic anhydride copolymers and vinyl acetate-maleic anhydride copolymers.
Although water and oil repellent treating agents are readily available, it is well known that they are expensive. Also, the efficiency in water and/or oil repellency is not always satisfactory. Furthermore, when they are employed for the treatment of textiles, they suffer from the disadvantage that they tend to give the treated textile a hard feeling. In order to overcome this problem, silicone softeners are commonly applied. However silicones are usually not compatible with the fluorochemical treating agent, and therefore, the treated substrates typically will show a decrease in water and oil repellency.
DISCLOSURE OF INVENTION
It is an object of the present invention to provide a water and oil repellency imparting composition which is less expensive and which can give higher water and oil repellency with a simple one step treatment technique. A further object of the invention is the provision of a water and oil repellency imparting composition that shows high compatibility with common silicone softeners, so as to give the treated substrate a soft feeling, while maintaining the oil and water repellency.
These objects could be achieved by a water and oil repellency imparting composition comprising:
(a) a fluoroaliphatic radical-containing agent; and
(b) a polymer comprising cyclic carboxylic anhydride groups,
with the proviso that the composition does not contain water if the fluoroaliphatic radical-containing agent is a water soluble or dispersible polyoxyalkylene compound and the polymer comprising cyclic carboxylic anhydride groups is a styrene-maleic anhydride copolymer or a vinyl acetate-maleic anhydride copolymer.
Applicants have found that a polymer comprising cyclic carboxylic anhydride groups when used together with a fluoroaliphatic radical-containing agent significantly increases the water and oil repellency imparting effect of the latter. It was also found that a significantly smaller amount of fluoroaliphatic radical-containing agent is required for imparting oil and water repellency to the treated substrate if a polymer comprising cyclic carboxylic anhydride groups is additionally used, whereas larger amounts are required when the fluoroaliphatic radical-containing agent is used alone. It was further found that the polymer comprising cyclic carboxylic anhydride groups when used together with a fluoroaliphatic radical-containing agent increases the compatibility of the latter with commonly used silicone softeners, hence treated substrates have a soft feeling while at the same time the high oil and water repellency is retained.
Briefly, in one aspect the present invention provides a water and oil repellency imparting composition for fibrous and other substrates, said composition comprising a fluorochemical-type, water and oil repellent agent (such as a fluoroaliphatic radical-containing polyacrylate or polyurethane) and a polymer comprising cyclic carboxylic anhydride groups. The composition can further optionally comprise other additives such as, e.g., a softener and/or a plasticizer. The composition can be applied, e.g., to a fibrous substrate by contacting the substrate with the composition, for example, by immersing it in a bath of the composition or by spraying the composition onto the substrate. The treated substrate is then dried to remove the solvent therefrom.
The composition of this invention imparts desirable water and oil repellency to the substrates treated therewith without adversely affecting other desirable properties of the substrate, such as soft hand (or feeling). The composition of the present invention can be used for providing water and oil repellency to fibrous substrates such as textiles, papers, non-woven articles or leather or to other substrates such as plastics, wood, metals, glass, stone and concrete.
DETAILED DESCRIPTION
An important feature of compositions of the present invention is that any of the known fluoroaliphatic radical-containing agents useful for the treatment of fabrics to obtain repellency of water and oily and aqueous stains can be used. Fluoroaliphatic radical-containing agents include condensation polymers such as polyesters, polyamides or polyepoxides and vinyl polymers such as acrylates, methacrylates or polyvinyl ethers. Such known agents include, for example, those described in U.S. Pat. Nos. 3,546,187; 3,544,537; 3,470,124; 3,445,491; 3,341,497 and U.S. Pat. No. 3,420,697. Further examples of such fluoroaliphatic radical-containing water and oil repellency imparting agents include those formed by the reaction of perfluoroaliphatic thioglycols with diisocyanates to provide perfluoroaliphatic group-bearing polyurethanes. These products are normally applied as aqueous dispersions for fiber treatment. Such reaction products are described, for example, in U.S. Pat. No. 4,054,592. Another group of compounds which can be used are fluoroaliphatic radical-containing N-methylolcondensation products. These compounds are described in U.S. Pat. No. 4,477,498. Further examples include fluoroaliphatic radical-containing polycarbodiimides which can be obtained by, for example, reaction of perfluoroaliphatic sulfonamido alkanols with polyisocyanates in the presence of suitable catalysts.
The fluorochemical component is preferably a copolymer of one or more fluoroaliphatic radical-containing acrylate or methacrylate monomers and one or more fluorine-free (or hydrocarbon) terminally ethylenically-unsaturated comonomers. Classes of the fluorochemical monomer can be represented by the formulas:
R.sub.f R.sup.1 OCOC(R.sup.2)═CH.sub.2
and
R.sub.f SO.sub.2 N(R.sup.3)R.sup.4 OCOC(R.sup.2)═CH.sub.2
where
R f is a fluoroaliphatic radical;
R 1 is an alkylene with, for example, 1 to 10 carbon atoms, e.g. methylene or ethylene, or is --CH 2 CH(OR)CH 2 --, where R is hydrogen or --COCH 3;
R 2 is hydrogen or methyl;
R 3 is hydrogen or an alkyl with, for example, 1 to 10 carbon atoms, e.g. methyl or ethyl; and
R 4 is an alkylene with, for example, 1 to 10 carbon atoms, e.g. methylene or ethylene.
The fluoroaliphatic radical, called Rf for brevity, is a fluorinated, stable, inert, preferably saturated, non-polar, monovalent aliphatic radical. It can be straight chain, branched chain, or cyclic or combinations thereof. It can contain heteroatoms, bonded only to carbon atoms, such as oxygen, divalent or hexavalent sulfur, or nitrogen. R r is preferably a fully-fluorinated radical, but hydrogen or chlorine atoms can be present as substituents if not more than one atom of either is present for every two carbon atoms. The R f radical has at least 3 carbon atoms, preferably 3 to 14 carbon atoms, and preferably contains about 40% to about 78% fluorine by weight, more preferably about 50% to about 78% fluorine by weight. The terminal portion of the Rf radical is a perfluorinated moiety, which will preferably contain at least 7 fluorine atoms, e.g., CF 3 CF 2 CF 2 --, (CF 3 ) 2 CF--, F 5 SCF 2 --. The preferred Rf radicals are fully or substantially fluorinated and are preferably those perfluorinated aliphatic radicals of the formula C n F 2n+1 -- where n is 3 to 14.
Representative examples of fluorochemical monomers are: ##STR1## Preferred co-monomers which can be copolymerized with the above-described fluoroaliphatic radical-containing monomers are not hydrophilic and include those selected from the group consisting of octadecylmethacrylate, 1,4-butanediol diacrylate, laurylmethacrylate, butylacrylate, N-methylolacrylamide, isobutylmethacrylate, vinylchloride and vinylidene chloride.
The relative weight ratio of the fluoroaliphatic monomer(s) to the hydrocarbon co-monomer(s) can vary as is known in the art, and generally the weight ratio of them will be 50-95:50-5.
The polymers comprising cyclic carboxylic anhydride groups which are used together with the fluoroaliphatic radical-containing agent include polymers wherein the cyclic carboxylic anhydride groups are integrated into the polymer chain as well as polymers wherein these groups are present as pendant cyclic carboxylic anhydride groups. The former include copolymers of a compound having a terminal ethylenically unsaturated bond and of a cyclic carboxylic anhydride having an ethylenically unsaturated bond whereas the latter include polymers and copolymers of ethylenically unsaturated compounds carrying the cyclic carboxylic anhydride groups as groups pending at the main polymer chain.
Suitable copolymers of a compound having a terminal ethylenically unsaturated bond and a cyclic carboxylic anhydride having an ethylenically unsaturated bond useful in the composition of this invention are described, for example, in U.S. Pat. No. 4,240,916 and U.S. Pat. No. 4,358,573. The cyclic carboxylic anhydride can be an alkyl or aryl substituted or unsubstituted cyclic carboxylic anhydride wherein the alkyl groups contain preferably up to 6 carbon atoms each and the cyclic group contains preferably 4 to 15 carbon atoms, such as maleic or itaconic anhydride. Preferred is maleic anhydride. The compound having a terminal ethylenically unsaturated bond is preferably a 1-alkene, styrene, α methylstyrene, a (meth)acrylic acid derivative, such as an acrylic or methacrylic acid ester, or a vinylether. Such monomers can be used alone or as mixtures. The cyclic carboxylic anhydride can be used in an amount of about 10-70, preferably about 35-70 mol percent. More preferably 45-60 mol percent of ethylenically unsaturated cyclic anhydride is copolymerized with 40-55 mol percent of at least one C 2 to C 30 aliphatic 1-alkene to produce a copolymer such as, e.g., a maleic anhydride/octadecene copolymer, maleic anhydride/decene copolymer, and maleic anhydride/tetradecene copolymer. It is also preferred to copolymerize 45-60 mol percent of a cyclic carboxylic anhydride with 40-50 mol percent of a vinylether of preferably less than 30 carbon atoms to produce a copolymer such as, e.g. a maleic anhydride/octadecyl vinylether copolymer or maleic anhydride/methylvinylether copolymer. It is further preferred to copolymerize 45-60 mole percent of a cyclic carboxylic anhydride with 40-55 mol percent styrene to produce, e.g. a maleic anhydride/styrene copolymer.
The copolymers of a compound having a terminal ethylenically unsaturated bond and a cyclic carboxylic anhydride having an ethylenically unsaturated bond preferably used in the invention are composed of subunits of the following formula (I): ##STR2## wherein the residues R 1 and R 2 may be both hydrogen or one of them is hydrogen and the other is an aliphatic or aromatic group of not more than 30 carbon atoms which may contain up to 5 heteroatoms, R 3 and R 4 are independently hydrogen or methyl, n is an integer of 50 to 1000 and m is an integer of at least 1, which value depends on the molar ratios of the monomers used.
R 1 or R 2 is preferably hydrogen, an alkyl group, an unsubstituted or C 1 -C 5 alkyl substituted phenyl group, an ether group, or a carboxylic ester group. If R 1 or R 2 is an alkyl group, it contains preferably up to about 28 carbon atoms, more preferably up to 22 carbon atoms. If R 1 or R 2 is an ether group or a carboxylic ester group, it contains preferably not more than 30 carbon atoms.
n is preferably an integer from 50 to 750, and m is preferably at least 1.
The residues R 1 and R 2 need not necessarily all be the same.
The most preferred copolymers are composed of subunits of the following formulae: ##STR3## wherein R 5 is hydrogen or alkyl having up to 30 carbon atoms, R 6 is alkyl with up to 30 carbon atoms and n is as defined above, the dashed line indicates that R 5 and OR 6 may be linked to either of the two carbon atoms while the other carries a second hydrogen atom.
Suitable polymers having pendant cyclic carboxylic anhydride groups include polyolefins and poly(meth)acrylic acid derivatives such as esters having such groups pendant at the main polymer chain. Specific examples are copolymers of octadecylmethacrylate (ODMA) with allylmethacrylate (AMA) grafted with maleic anhydride, or polybutadiene polymers grafted with maleic anhydride.
The ratio of fluoroaliphatic radical-containing agent to polymer comprising cyclic carboxylic anhydride groups is preferably between 1:0.02 and 1:3, more preferably between 1:0.05 and 1:1.5 by weight.
The composition of the present invention may further comprise other additives usually employed in oil and water repellency imparting compositions, such as softeners, e.g., silicone softening agents, and/or plasticizers. The softening agent will increase the soft feeling of the treated substrate. Suitable silicone softening agents include those selected from the group consisting of polydimethylsiloxanes, and polyhydroxymethylsiloxanes. If used, the softening agent is present in an amount between 5% and 300% by weight, preferably between 15% and 200% by weight, based on the fluoroaliphatic radical-containing agent.
Suitable plasticizers include aliphatic or aromatic esters, such as dioctyladipate, dioctylazelate, ditridecyladipate, di(2-ethylhexyl)azelate, di(2-ethylhexyl)maleate, diethylhexylsebacate, butylbenzylphtalate, dioctylphtalate, dibutylphtalate, diisodecylphtalate, ditridecylphtalate, and diisononylphtalate; polyester type plasticizers such as Priplast plasticizers (available from Unichema Chemie GmbH, Emmerich, GERMANY) paraffins and substituted paraffins, such as Chlorparaffins (available from Hus AG, Marl, GERMANY) epoxy type plasticizers, such as Rheoplast plasticizers (available from Ciba-Geigy AG, Basel, SWITZERLAND). If used, the plasticizer is present in an amount of between 10 and 200%, preferably between 20 and 100% by weight of the fluoroaliphatic radical-containing agent.
For application, the water and oil repellency imparting composition can be used in solvent solution, emulsion and aerosol forms. Preferably, the composition is used in solvent solution form.
Suitable solvents are those that are capable of solubilizing the fluoroaliphatic radical-containing agent, the polymer comprising cyclic carboxylic anhydride groups and the optional silicone softener and plasticizer. Suitable solvents include chlorinated hydrocarbons, isoparaffinic hydrocarbons, alcohols, esters, ketones and mixtures thereof. Usually, the solvent solutions will contain 0.1 to 10% or even up to 50% by weight solids.
Water is not used as a solvent for the water and oil repellency imparting composition of the present invention if the fluoroaliphatic radical-containing agent is a water soluble or dispersible polyoxyalkylene compound and the polymer comprising cyclic carboxylic anhydride groups is a styrene-maleic anhydride copolymer or a vinyl acetate-maleic anhydride copolymer. As the presence of water in solutions of the compositions of the invention may cause ring opening of the cyclic anhydride which will impair the performance properties of the cyclic anhydride copolymer, it is generally preferred beyond the above restriction that solutions of the compositions of the invention are substantially water free. This means that solutions of the composition of the present invention preferably do not contain more than 5% by weight, more preferably not more than 1% by weight, and still more preferably not more than 0.5% by weight of water, based on the total weight of the composition. Most preferably the compositions of the invention and their solutions do not contain any water.
The amount of the composition applied to a substrate in accordance with this invention is chosen so that sufficiently high or desirable water and oil repellencies are imparted to the substrate surface, said amount usually being such that 0.01% to 5% by weight, preferably 0.05 to 2% by weight, based on the weight of the substrate, of fluoroaliphatic radical-containing agent and polymer comprising cyclic carboxylic anhydride groups is present on the treated substrate. The amount which is sufficient to impart desired repellency can be determined empirically and can be increased as necessary or desired.
The treatment of fibrous substrates using the water and oil repellency imparting composition of the present invention is carried out by using well-known methods including dipping, spraying, padding, knife coating, and roll coating. Drying of the substrate is done at 120° C. or below, including room temperature, e.g. about 20° C. with optionally heat-treating the textile products in the same manner as in conventional textile processing methods.
The substrates treated by the water and oil repellency imparting composition of this invention are not especially limited and include, e.g., textile fabrics, fibers, nonwovens, leather, paper, plastic, wood, metal, glass, concrete and stone.
Respective data of water and oil repellency shown in the Examples and Comparative Examples are based on the following methods of measurement and evaluation criteria:
Spray Rating
The spray rating (SR) of a treated substrate is a value indicative of the dynamic repellency of the treated substrate to water that impinges on the treated substrate, such as encountered by apparel in a rain storm. The rating is measured by Standard Test Number 22, published in the 1977 Technical Manual and Yearbook of the American Association of Textile Chemists and Colorists (AATCC), and is expressed in terms of the "spray rating" of the tested substrate. The spray rating is obtained by spraying water on the substrate and is measured using a 0 to 100 scale where 100 is the highest possible rating.
Oil Repellency
The oil repellency (OR) of a treated substrate is measured by the American Association of Textile Chemists and Colorists (AATCC) Standard Test Method No. 118-1983, which test is based on the resistance of treated substrate to penetration by oils of varying surface tensions. Treated substrates resistant only to Nujol®, mineral oil (the least penetrating of the test oils) are given a rating of 1, whereas treated substrates resistant to heptane (the most penetrating of the test oils) are given a rating of 8. Other intermediate values are determined by use of other pure oils or mixtures of oils, as shown in the following table.
______________________________________Standard Test LiquidsAATCC Oil RepellencyRating Number Composition______________________________________1 Nujol ®2 Nujol ®/n-hexadecane 65/353 n-Hexadecane4 n-Tetradecane5 n-Dodecane6 n-Decane7 n-Octane8 n-Heptane______________________________________
Abbreviations:
The following abbreviations and trade names are used in the examples:
______________________________________PA-18: 1:1 Copolymer of 1-octadecene with maleic anhydride having a molecular weight of about 30000 to 50000, available from Chevron Chemical Company, Geneve, SWITZERLANDMA: maleic anhydrideODMA: octadecylmethacrylateAMA: allylmethacrylateODVE: octadecyl vinyletherGANTREZ AN119: Copolymers of polymethyl vinyletherGANTREZ AN169: with maleic anhydride; MN = 20000GANTREZ AN179: (GANTREZ AN119), Mn = 67000 (GANTREZ AN169) and Mn = 80000 (GANTREZ AN179), available from GAF chemical Corp., Wayne N.J., U.S.A.SMA 3000A: Styrene-maleic anhydride copolymer, available from Atochem S.A., Paris, FRANCEBaysilan Ol M3 Polydimethylsiloxane,(Bay Ol M3): available from Bayer AG., Leverkusen, GERMANYLithene LX16-10MA: Liquid Polymers of ButadieneLithene chemically modified byN4-5000-10MA: 10 weight % MA (LX16-10MA and N4-Lithene PM25MA: 5000-10MA) or 25 weight % MA (PM- 25-MA), available from Revertex, Harlow, U.K.SH8011: A 50% solution in mineral spirits of polydimethylsiloxane, polyhydroxymethylsiloxane and Zn(BF.sub.4).sub.2 available from Toray Industries Inc., Tokyo, JAPANWacker CT 51L A 25% solution in toluene of a(Wa CT 51L): high molecular weight silicone, available from WackerChemie GmBH, Munich, GERMANYWPU: Wet pick upSOF: Solids on fibreMIBK: Methyl isobutyl ketoneDOZ: Dioctylazelate______________________________________
EXAMPLE
The following examples are intended to be illustrative and should not be construed as limiting the invention in any way. All parts, ratios, percentages, etc. in the examples and the rest of the specification, are by weight unless otherwise noted.
Fluoroaliphatic radical-containing agents
The fluoroaliphatic radical-containing agents used in the examples of the present invention are commercially available from 3M:
FX-3530 is a fluoroaliphatic radical-containing polymethacrylate, sold as a 25% solution of fluoropolymer in ethylacetate/heptane.
FX-3532 is a fluoroaliphatic radical-containing polyurethane, sold as a 40% solution of fluoropolymer in ethylacetate.
FX-3534 is a fluoroaliphatic radical-containing polymethacrylate, sold as a 30%; solution of fluoropolymer in methylethylketone.
______________________________________Commercially available substrates______________________________________Pes/Co Utex: Grey polyester/cotton 65/35, style No. 2681, obtained through Utexbel N.V., Ghent, BELGIUM.100% Cotton: Bleached, mercerized cotton poplin, style No. 407, purchased from Testfabrics, Inc., U.S.A.100% Silk: YIS Colour fastness test substrate.______________________________________
Synthesis of polymers comprising cyclic carboxylic anhydride groups in the polymer main chain.
Several polymers comprising cyclic carboxylic anhydride groups as given in Table 1 have been prepared according to the general method as described below (as cyclic carboxylic anhydride, maleic anhydride was used):
In a three necked flask equipped with a mechanical stirrer, a nitrogen inlet and a condenser were placed a compound having a terminal ethylenically unsaturated bond and maleic anhydride in a solvent at 50% solids (30% in case of the (meth) acrylic esters). The solvent used is listed in Table 1. To this mixture was added 2% by weight of azobisisobutyronitrile (AIBN), based on monomer weight (0.3% in case of the (meth) acrylic esters, plus 0.3% n-octylmercaptan). The reaction mixture was purged with nitrogen and reacted at 72° C. under nitrogen during 16 hours (20 hours in case of the (meth)acrylic esters). In all cases clear viscous solutions were obtained.
TABLE 1______________________________________Preparation of polymers comprisingcyclic carboxylic anhydride groupsin the polymer main chainCompound Mol Ratio MaleicUsed Having a Anhydride/Compoundin Terminal Having a TerminalEx. Ethylenically EthylenicallyNo. Unsaturated Bond Unsaturated Bond Solvent______________________________________33 1-Octadecyl 50:50 Toluenevinylether34 1-Hexadecene 50:50 Toluene35 1-Decene 50:50 Toluene36 1-Tetradecene 50:50 Toluene37 1-Hexene 50:50 MIBKC-13 Octadecyl- 0:100 Ethylacetatemethacrylate71 Octadecyl 45:55 EthylacetatemethacrylateC-14 Butylmethacrylate 0:100 Ethylacetate72 Butylmethacrylate 26:74 Ethylacetate73 Butylmethacrylate 49:51 Ethylacetate______________________________________
Molecular weight analysis of the polymers comprising cyclic carboxylic anhydride groups in the polymer main chain.
The GPC (gel phase chromatography) analysis has been done using a Perkin Elmer Series 400 pump autosampler from Polymer Laboratories. The columns (30 cm-0.46 cm) are packed with PL gel (polystyrene crosslinked with divinylbenzene) with a particle size of 10 micron. The eluent used is THF (tetrahydrofuran). Flow rate: 1 ml/min. The calibration is done with polystyrene standards having molecular weights between 1200 and 2,950,000. The flow rate marker is toluene. The molecular weight is calculated with a PL GPC data station version 3.0. Detection is done with a PE LC25 refractive index detector. The results of the analysis are given in Table 2 below: Mw is the weight average molecular weight; Mp is the peak molecular weight; Mn is the number average molecular weight and p is the polydispersity (Mw/Mn).
TABLE 2______________________________________Molecular weight analysisCopolymer of MaleicAnhydride with Mn Mw Mp p______________________________________1-octadecyl 131 832 145 622vinylether1-Hexadecene 6 017 11 324 9 228 1.91-Decene 5 400 12 427 10 975 2.31-Tetradecene 7 092 11 924 9 890 1.71-Hexene 7 759 14 390 11 227 1.9______________________________________
Synthesis of polymers comprising pendant cyclic carboxylic anhydride groups
(Meth)acrylate polymers comprising pendant cyclic carboxylic anhydride groups have been prepared according to the general method as described below:
In three necked flasks equipped with a mechanical stirrer, a nitrogen inlet and a condenser were placed octadecyl methacrylate and allylmethacrylate in a ratio of 90/10 and 80/20, respectively. The monomers were diluted with butylacetate to 40%. To these mixtures was added 0.75% by weight of initiator azobisisobutyronitrile (AIBN), and 1% chain transfer agent n-octylmercaptan (based on monomer weight). The reaction mixtures were purged with nitrogen and reacted at 72° C. under nitrogen during 16 hours.
In a second step, maleic anhydride was grafted to the methacrylic polymers, according to the following method:
To the allyl (meth)acrylate copolymers prepared as described above, maleic anhydride was added in an amount to provide a 1/1 molar ratio of the maleic anhydride to the allyl(meth)acrylate. Additional 1% AIBN based on the total solids was added and the mixtures were further diluted with butylacetate to 30% solids. The mixtures were purged with nitrogen and further reacted at 72° C. for another 16 hours.
The copolymers ODMA/AMA 90/10 and 80/20, grafted with MA are evaluated in examples 74 and 75, respectively. The copolymers ODMA/AMA 90/10 and 80/20 that were not grafted with MA are used in comparative examples C-16 and C-17 (see also table 13).
Examples 1 to 6 and Comparative Examples C-1 to C-3
In examples 1 to 6, blends were made of FX-3530, FX-3532 or FX-3534 with PA-18 in MIBK in different ratios as given in Table 3. The blends were applied to Pes/Co Utex fabric by solvent padding, at 100% WPU. The fabrics were dried at 70° C. for 30 minutes. Alternatively, the fabrics were additionally ironed at 150° C. for 5 sec. Comparative examples C-1 to C-3 were made without the addition of PA-18. In all cases, the tests were done in a way to give a concentration of the treating solution of 0.3% solids on fibre. The results are given in Table 3.
TABLE 3______________________________________Performance properties of Pes/co Utexsubstrate treated with fluoroaliphaticradical-containing agent-PA-18 mixturesFluoroaliphatic Dried +Ex. Radical-Containing Ratio* Dried IronedNo. Agent (FC) FC/PA-18 OR SR OR SR______________________________________1 FX-3530 90/10 4 100 4 1002 FX-3530 80/20 4 100 4 1003 FX-3532 90/10 4 70 4 704 FX-3532 80/20 4 70 4 705 FX-3534 90/10 4 100 4 1006 FX-3534 80/20 4 100 4 100C-1 FX-3530 100/0 4 70 4 80C-2 FX-3532 100/0 4 50 5 50C-3 FX-3534 100/0 4 90 4 90______________________________________ Note: Ratio *: weight % of solid material
The results of the experiments shown in this table indicate that in all cases an improvement of the spray rating is observed, even when small amounts (10%) of the fluoroaliphatic radical-containing agent are replaced by PA-18. The oil repellency rating remains at the same high level.
Examples 7, 8 and Comparative Example C-4
In example 7, a treatment solution containing FX3530, PA-18 and dioctylazelate plasticizer in MIBK was used. Example 8 was carried out the same way, except that SMA 3000A was used instead of PA-18.
Comparative example C-4 was carried out in the same way but no polymer comprising cyclic carboxylic anhydride groups was used.
The treatment solutions were applied to different substrates by solvent padding, at 100% WPU. The treated fabrics were dried at room temperature, eventually followed by a heat treatment for 15 sec at 150° C. (ironed). This method provided the fabrics with 0.3% SOF FX-3530, 0.06% SOF polymer comprising cyclic carboxylic anhydride groups (except for C4) and 0.15% SOF plasticizer. The results are given in Table 4.
TABLE 4__________________________________________________________________________Performance properties of substratestreated with mixtures of fluoroaliphaticradical-containing agent and polymercomprising cyclic carboxylic anhydride groups.PolymerComprisingCyclic Carboxylic 100% Cotton SilkEx. Anhydride Air Dry Ironed Air Dry IronedNo. Groups OR SR OR SR OR SR OR SR__________________________________________________________________________7 PA-18 4 100 3 100 4 100 4 958 SMA 3000A 4 80 2 80 3 90 4 85C-4 / 3 60 1 70 4 80 4 80__________________________________________________________________________
Again, it is shown that the tested treatment solutions containing a polymer comprising cyclic carboxylic anhydride groups give improved oil and water repellency as compared to the fluorochemical treatment solution without such polymers added. Both SR and OR values indicate that it is not required to give the fabric a heat curing treatment after application.
Example 9 and Comparative Example C-5
The same kind of experiment as outlined for Example 4 was repeated but the treatment solutions were made in perchloroethylene for dry clean applications and no additional plasticizer was used. As substrate, Pes/Co Utex was chosen and the composition was applied by solvent padding to give a total of 0.1% SOF (0.08% SOF FX-3530 and 0.02% SOF PA-18 for example 9 and 0.1% SOF FX-3530 for C-5) after drying, which is a typical add-on for dry clean applications. The treated substrates have been dried at 70° C. for 30 min, eventually followed by ironing at 100° C. for 5 sec. Comparative example C-5 was made without PA-18. The results are given in Table 5.
TABLE 5______________________________________Performance properties of substrates treated withFX-3530 with and without PA-18, respectively. Dried Dried + IronedEx. No. OR SR OR SR______________________________________9 1 80 1 100C-5 0 50(W) 0 50(W)______________________________________ Note: (W): Reverse side is wet
The sample with the PA-18 reaches the minimum requirement for dry clean application, being an oil repellency rating of 1 and a spray rating of 100 after ironing.
Examples 10 to 19 and Comparative Example C-6
In examples 10 to 13, FX-3530 was gradually replaced by PAl8, so as to obtain a constant level of 0.3% solids on fibre after drying. In examples 14 to 19, the level of FX-3530 was kept constant at 0.3% SOF and the amount of PA-18 was gradually increased. Comparative Example C-6 was made without the addition of PA-18. All treatment solutions in MIBK of examples 10 to 19 and Comparative Example C-6 were applied to Pes/Co Utex fabric. After treatment, the fabric was dried at 70° C. for 30 min, eventually followed by heat treatment at 150° C. for 5 sec (ironed). The results of oil and water repellency test are given in Table 6.
TABLE 6______________________________________Performance properties of Pes/Co Utex substratetreated with FX-3530 - PA-18 in different ratios Dried +Ex. Dried IronedNo. % SOF FX-3530 PA-18 OR SR OR SR______________________________________10 0.24 0.06 4 100 4 10011 0.18 0.12 3 100 3 10012 0.12 0.18 2 100 2 10013 0.06 0.24 1 90 1 9014 0.3 0.03 4 100 3 10015 0.3 0.06 4 100 3 10016 0.3 0.12 4 100 3 10017 0.3 0.18 4 100 3 10018 0.3 0.3 4 100 4 10019 0.3 0.6 5 100 4 100C-6 0.3 0 4 80 3 80______________________________________
The results indicate that even a small amount of PA-18 gives a significant improvement of the spray rating. The performance of the treated samples remain high, even when about half of the amount of FX-3530 is replaced by PA-18. The addition of higher amounts (higher than 0.3% SOF) of PA-18 to the fluoroaliphatic radical-containing agent does not increase the performance of the treated samples substantially, but it does not deteriorate the performance either.
Examples 20 to 22 and comparative Examples C-7 to C-9
In the examples 20 to 22 various silicone softening agents were evaluated in combination with the water and oil repellency imparting compositions of the present invention, to improve the softness of the treated fabric. Treatment solutions were applied to the fabrics by solvent padding, to give a concentration of 0.3% SOF of silicone softener, 0.3 SOF of FX-3530, 0.15% SOF Dioctylazelate and 0.06%; SOF of PA-18. Comparative examples C-7 to C-9 were made without addition of PA-18.
All treatment solutions (in MIBK) were applied to the fabric by solvent padding. The treated fabrics are dried at room temperature (examples 20 and 21 and comparative examples C-7 and C-8) or at 70° C. for 30 min (example 22 and comparative example C-9) eventually followed by heat cure at 150° C. for 15 sec (Ironed). The results are given in Table 7.
TABLE 7__________________________________________________________________________Performance properties of substrates treatedwith mixtures of FX-3530, PA-18 and silicone softener 100% Cotton Pes/co UtexEx. Silicone PA-18 Dried Ironed Dried IronedNo. type SOF OR SR OR SR OR SR OR SR__________________________________________________________________________20 SH8011 0.3 6 100 3 100 5 100 3 100C-7 SH8011 0 3 90 3 90 5 100 3 10021 BayOl M3 0.3 2 100 2 100 1 100 2 100C-8 BayOl M2 0 4 70 4 70 4 60 4 6022 Wa CT51L 0.3 5 100 5 100C-9 Wa CT51L 0 5 70 5 70__________________________________________________________________________ Note: the samples containing Wacker CT 51L contain 0.13% SOF dioctylazelate.
In most cases, the addition of PA-18 increases the spray rating of the treated fabric. Except for the Baysilan 01 M3, the oil rating remains about the same.
Examples 23 to 29 and Comparative Example C-10
In examples 23 to 29, different amounts of PA-18 were used in combination with FX-3530 (0.3% SOF), silicone softener SH8011 (0.3% SOF) and Dioctylazelate plasticizer (0.15 SOF). The treatment solutions were applied to 100% cotton by solvent padding (MIBK). The treated substrates were dried at room temperature and conditioned overnight before testing. Comparative example C-10 was made without PA-18. The results of oil repellency and spray rating are given in Table 8.
TABLE 8______________________________________Performance properties of 100%cotton treated with FX-3530/PA-18 PA-18, % of 100% FX-3530 CottonEx. No. PA-18, % SOF Solids OR SR______________________________________23 0.006 2 5 9024 0.015 5 5 9525 0.03 10 5 10026 0.06 20 5 10027 0.15 50 5 10028 0.3 100 5 10029 0.6 200 5 100C-10 0.0 0 4 90______________________________________
The results indicate that even a very small amount of PA-18 causes already an increase in oil repellency. It is also clear that there is no real limit on the addition of PA-18. Preferably a minimum amount of PA-18 of 5% of the FX-3530 solids is used.
Examples 30 to 37 and Comparative Example C-11
In examples 30 to 37 blends were made of FX-3530 with different polymers comprising cyclic carboxylic anhydride groups in MIBK in a ratio of 80/20. The blends were applied to Pes/Co Utex fabric by solvent padding, at 100% WPU. The fabrics were dried at 65° C. for 30 minutes, eventually also ironed at 150° C. for 5 sec. Comparative example C-11 was made without the addition of such a polymer. The test was done in a way to give a concentration of the treating composition of 0.3% solids on fibre. The results of testing are given in Table 9.
TABLE 9______________________________________Performance properties of Pes/Co Utexsubstrate treated with mixtures offluoroaliphatic radical containingagent and a polymer comprising cycliccarboxylic anhydride groups Polymer comprising Dried +Ex. Cyclic Carboxylic Dried IronedNo. Anhydride Groups OR SR OR SR______________________________________30 Gantrez AN119 2 100 2 10031 Gantrez AN169 2 100 2 10032 Gantrez AN179 2 100 2 10033 ODVE/MA 3 90 2 10034 Hexadecene/MA 3 100 3 10035 Decene/MA 2 100 2 10036 Tetradecene/MA 3 100 3 10037 Hexene/MA 3 100 2 100C-11 / 3 80 3 80______________________________________
Although 20% of the fluoroaliphatic radical-containing agent is replaced by a polymer comprising cyclic carboxylic anhydride groups, very little influence is seen on the oil repellency of the treated sample. Moreover, the water repellency is increased.
Examples 38-, to 57
In examples 38 to 57 different plasticizers were evaluated in the water and oil repellency imparting composition of the present invention. In all examples, a solution in MIBK of FX-3530 (0.3% SOF), silicone softener SH8011 (0.3% SOF), PA-18 (0.06% SOF) and plasticizer (0.15% SOF) was used to treat a 100% cotton substrate. The treated substrate was dried at room temperature and conditioned overnight before testing. The results are given in Table 10.
TABLE 10______________________________________Performance properties of 100%cotton substrate treated withfluoroaliphatic radical-containing agent,polymer comprising cyclic carboxylic anhydridegroups, silicone softener and plasticizer. 100% CottonEx. No. Plasticizer Type OR SR______________________________________38 Chlorparaffin 45 G 5 10039 Chlorparaffin 40 N 5 9540 Chlorparaffin 52 G 5 9541 Chlorparaffin 40 G 5 10042 Priplast 3124 6 9543 Priplast 3155 5 9044 Priplast 3114 5 10045 Priplast 3126 5 10046 Priplast 3157 5 10047 Priplast 3159 5 10048 Ditridecyladipate 6 10049 Dioctylazelate 6 10050 Diethylhexylsebacate 6 10051 Diisodecylphtalate 6 10052 Dibutylphtalate 3 10053 Dioctylphtalate 6 10054 Butylbenzylphtalate 6 10055 Ditridecylphtalate 6 10056 Diisononylphtalate 6 10057 Rheoplast 39 6 100______________________________________ Notes: Chlorparaffin: available from Huls Priplast: available from Unichema Rheoplast 39: epoxytype plasticizer from CibaGeigy
The results in this table indicate that the performance of the treated substrate is high, independent of the structure of the added plasticizer.
Examples 58 to 70
In examples 58 to 70 the amount of the plasticizer has been varied. In all cases, solutions in MIBK of FX-3530 (0.3% SOF), PA-18 (0.06% SOF), silicone softener SHBOll (0.3% SOF) and plasticizer (various amounts as given in table 11) were applied to 100% cotton. The plasticizers evaluated were butylbenzylphtalate (BBP) and dioctylazelate (DOZ). The treated substrates were dried at room temperature and conditioned overnight before testing. The results of oil repellency and spray rating are given in Table 11.
TABLE 11______________________________________Performance properties of 100% cottonsubstrate treated with fluoroaliphatic radical-containing agent, polymer comprising cyclic carboxylicanhydride groups, silicone softener and plasticizer PlasticizerEx. Plasticizer % Solids 100% CottonNo. Type SOF of FX-3530 OR SR______________________________________58 / 0 0 1 10059 BBP 0.015 5 1 10060 BBP 0.03 10 1 10061 BBP 0.06 20 2 10062 BBP 0.15 50 4 10063 BBP 0.3 100 5 10064 BBP 0.6 200 5 10065 DOZ 0.015 5 2 10066 DOZ 0.03 10 2 10067 DOZ 0.06 20 3 10068 DOZ 0.15 50 5 10069 DOZ 0.3 100 5 10070 DOZ 0.6 200 4 100______________________________________
The results in this table indicate that it is preferable to add a plasticizer to the treatment solution of the present invention when a silicone softener is also used. The plasticizer can be added in various amounts, but preferably it is added at a minimum of 20% of the fluoroaliphatic radical-containing agent solids.
Examples 71 to 73 and Comparative Examples C-12 to C-14
In examples 71 to 73, FX-3530 was gradually replaced by the copolymers of (meth)acrylic acid esters with maleic anhydride as given in Table 1, so as to obtain a constant level of 0.3% solids on fabric after drying. Comparative Example C-12 was made without the addition of such a copolymer. In Comparative Examples C-13 and C-14 a homopolymer of the (meth)acrylic acid ester was used. All treatment solutions in MIBK of Examples 71 to 73 and Comparative Examples C-12 to C-14 were applied to Pes/Co Utex fabric. After treatment the fabric was dried at 70° C. for 30 min, eventually followed by heat treatment at 150° C. for 5 sec (ironed). The results of oil and water repellency tests are given in Table 12.
TABLE 12______________________________________Performance of Pes/Co Utex fabrictreated with FX-3530 and (meth)acrylicacid ester/maleic anhydride copolymers of(meth)acrylic acid ester homopolymers Dried +Ex. FX-3530 Copolymer Dried IronedNo. Solids Solids OR SR OR SR______________________________________C-12 0.3 4 80 3 80C-13 0.24 0.06 4 80 4 8071 0.24 0.06 4 100 4 100C-14 0.24 0.06 4 80 3 10072 0.24 0.06 4 90 3 9073 0.24 0.06 4 100 3 100______________________________________
Examples 74 to 78 and Comparative Examples C-15 to C-17
In examples 74 to 78 blends were made of FX-3530 (0.3% SOF) with polymers comprising pendant cyclic carboxylic anhydrides (0.06% SOF) as given in table 13. Comparative example C-15 was made without the addition of a polymer comprising pendant cyclic anhydrides. In comparative examples C-16 and C-17, methacrylic acid ester copolymers of ODMA/AMA without grafted MA were used. The blends were applied to Pes/Co Utex fabric by solvent padding (MIBK), at 100% WPU. The fabrics were dried at 60° C. for 30 minutes. Alternatively, the fabrics were additionally ironed at 150° C. for 5 sec. The results of the performance of the treated fabrics are given in table 13.
TABLE 13______________________________________Performance properties of Pes/Co Utexsubstrate treated with fluoroaliphatic radical-containing agent (0.3% SOF) and polymer comprisingpendant cyclic carboxylic anhydride groups (0.06% SOF) Pes/Co UtexPolymer comprising Dried +Ex. pendant cyclic Dried IronedNo. carboxylic anhydride OR SR OR SR______________________________________74 (ODMA/AMA 90/10)/MA 5 90 4 10075 (ODMA/AMA 80/20)/MA 5 100 4 10076 Lithene LX-16-10MA 3 100 3 10077 Lithene N4-5000-10MA 3 100 3 10078 Lithene PM-25MA 3 100 4 100C-15 / 4 70 3 70C-16 ODMA/AMA 90/10 5 70 4 70C-17 ODMA/AMA 80/20 4 70 4 70______________________________________
The results in table 13 indicate that the addition of a polymer comprising pendant cyclic carboxylic anhydride groups to the fluoroaliphatic radical-containing agent gives an overall higher performance of the treated fabric. | The invention relates to a water and oil repellency imparting composition which comprises:
(a) a fluoroaliphatic radical-containing agent; and
(b) a polymer comprising cyclic carboxylic anhydride groups.
Additionally, the composition may comprise:
(c) a softener and/or a plasticizer. The composition provides water and oil repellent properties to fibrous and other substrates treated therewith and it shows high compatibility with the commonly used softeners. | 3 |
BACKGROUND OF THE INVENTION
This invention generally relates to an improved process for preparing derivatives of mercaptophenols. Further, the invention provides for an improved process for preparing hindered phenol sulfides containing a nitrile, carbonyl, sulphone or ester group from the reaction of mercaptophenols with vinyl compounds containing a conjugated nitrile, carbonyl, sulphone or ester group.
The prior art generally teaches the preparation of mercaptophenol derivatives which are extremely useful as stabilizers for various organic and polymeric materials. A number of mercaptophenol derivatives are known to be useful as antioxidants and in pharmaceutical applications. In particular, Japanese Application No. 47-115575 discloses the preparation of mercaptophenol derivatives containing nitrile or carbonyl groups. European Patent Application No. 82810476.0 discloses mercaptophenols containing ester groups with improved stabilizer performance and U.S. Pat. No. 4,311,637 discloses polyphenolic esters of mercaptophenols useful as antioxidants.
The compounds disclosed by the prior art are generally produced by reacting the components in the presence of a proton acceptor. Typically, the proton acceptors are chosen from bases such as lithium salts, alkali metals, alkali and alkaline earth hydroxides, alkaline earth carbonates and tertiary amines. In addition, the reaction is generally carried out in non-polar solvents such as benzene, toluene and xylene or, alternatively without solvent. While such techniques are adequate to react the components, the processes suffer from slow reaction rates and, consequently produce by-products. In particular, the by-product disulfide is formed from the mercaptophenol due to the presence of traces of oxygen. Further, the predominant use of inorganic proton acceptors results in formation of salts which are not easily removed from the final product.
Japanese Patent Application No. 47-115575 discloses the use of non-polar solvents and polar solvents such as acetonitrile, dioxane, and pyridine; however, it requires the use of a suitable base such as alkali metal, alkali hydroxides and ammonium salts. The reaction times varied from 6 to 8 hours and the final product was recrystallized with n-hexane in order to purify the product.
Due to the difficulties and costs caused by slow reaction times and removal of by-products, it would be desirable to improve the process for preparation of mercaptophenol derivatives. Surprisingly, it has been discovered that by employing an amine base catalyst in a polar solvent the reaction between mercaptophenols and vinyl compounds containing nitrile, carbonyl, sulphone or ester groups proceeds rapidly to form the desired product with very little disulfide formation and; therefore, the product is of high purity. Further, the catalyst can be easily removed by co-distillation with the solvent.
SUMMARY OF THE INVENTION
The invention provides for an improved process for preparing derivatives of mercaptophenols containing nitrile, carbonyl, sulphone or ester groups by reacting a mercaptophenol with a vinyl compound containing a conjugated nitrile, carbonyl, sulphone or ester group. The process is characterized by reacting said mercaptophenol and said vinyl compound in a polar solvent with an amine catalyst. The process temperature is not critical and can be from 0° C. to about the reflux temperature of the polar solvent employed. The preferred amine catalyst is a tertiary amine.
Additionally, the process can include the step wherein the amine catalyst is removed by co-distillation with the polar solvent. The preferred polar solvent is acetonitrile and the preferred amine catalyst is triethyl amine.
Some advantages provided by the subject process are rapid formation of the desired product with very little formation of contaminants and ease of catalyst removal. Further, the product has a high degree of purity without additional purification steps.
DETAILED DESCRIPTION OF THE INVENTION
The improvement of the present invention relates to a process which generally comprises reacting mercaptophenols and vinyl compounds containing a nitrile, carbonyl, sulphone or ester groups as is well known in the art. The improvement comprises reacting the components in a polar solvent with an amine based catalyst. The use(s) of the compounds prepared from mercaptophenols and vinyl compounds containing a nitrile, carbonyl, sulphone or ester group is generally well known in the art and is taught in various publications disclosed herein.
Generally, the reaction of mercaptophenols with the vinyl compound can be structurally depicted as follows: ##STR1##
As shown above the R groups are independently a hydrogen, an alkyl group, an alkaryl group or a hydroxyaryl group, R 1 is a nitrile, carbonyl, sulphone or ester group and R 2 is a hydrogen or alkyl group.
With respect to the mercaptophenol compound, the preferred species comprises 2,6-di-t-butyl-4-mercaptophenol. Other suitable mercaptophenols are taught in U.S. Pat. Nos. 4,012,523 and 4,311,637 and European Patent Application No. 82810476.0.
With regard to the various vinyl compounds that can be employed, the acrylate esters such as methyl acrylate, maleic anhydride, 1,6-hexanediol diacrylate and reaction products of hydroxyethyl acrylate and isocyanatoalkyl methacrylate are preferred. The vinyl compounds can also comprise α,β-unsaturated ketones, aldehydes, carboxylic anhydrides, nitriles and sulphones. Other suitable vinyl compounds containing conjugated nitrile, carbonyl, sulphone and ester groups are considered within the scope of this invention. Suitable vinyl compounds are those containing electron withdrawing groups. Vinyl compounds containing a conjugated carbonyl group can include α,β-unsaturated ketones and aldehydes, and α,β-unsaturated carboxylic anhydrides.
More generally, the reaction of mercaptophenols and vinyl compounds containing nitrile, carbonyl, sulphone and ester groups for the preparation of useful mercaptophenol derivatives is disclosed in U.S. Pat. Nos. 4,311,637 and 4,012,523, European Application No. 82810476.0 and Japanese Publication KOKAI No. 49-75551/1974.
The subject invention is characterized by reacting the various mercaptophenol and vinyl compounds taught above, in a polar solvent with an amine catalyst. When the reaction is carried out by the subject invention a product of high purity is rapidly formed with very little by-product, i.e., disulfide formation. Further the product does not contain difficult to remove catalyst or catalyst by-product as the amine catalyst can be removed by co-distillation with the solvent.
Generally, the polar solvents include those solvents which are polar in nature and are non-reactive solvents with the reaction components. Representative polar solvents which can be employed are acetonitrile, isopropanol, methanol, ethanol and the like. Methylene chloride can also be employed; however, it does not perform as well as other polar solvents. Therefore, polar solvents exhibiting polar characteristics greater than or equal to methylene chloride are preferred. The polar characteristic of a solvent can be easily predicted from standard tables of dielectric constants and polarity index. One such preferred polar solvent is acetonitrile.
With respect to the catalyst employed in the improved process, it has been found that the group of non-reactive amine catalysts perform especially well when dispersed in the polar solvent described above. What is meant by "non-reactive amine catalyst" is that the catalyst does not react with other components produced or present in the subject reaction such that the activity of the catalyst is impaired. The use of an amine catalyst is especially preferred due to its ease of removal from the final reaction product by distillation. Further, the amine catalyst is highly soluble in the polar solvent which contributes to its excellent activity and ability to be co-distilled from the final product. Preferably, the amine catalysts are non-reactive tertiary amines, of a base strength similar to triethylamine, trimethylamine and tributylamine. The most preferred amine catalyst is triethylamine.
The improved reaction of the subject invention generally proceeds under commonly employed reaction conditions for the particular reaction component. That is, the reaction can be conducted from about 0° C. to the reflux temperature of the polar solvent or particular reactants employed. Naturally, lower temperatures would detract from the improved reaction rate. More particularly, the reaction rate is dependent on various variables present in the system such as temperature, concentration of reactants and the mutual solubilities of the components.
The following example is provided to demonstrate the improved process of the invention.
EXAMPLE I
Reaction of 2,6-Di-t-butyl-4-mercaptophenol with Tetraethyleneglycol Diacrylate.
A solution of 1.84 g of tetraethyleneglycol diacrylate and 10.0 ml of nitrogen purged acetonitrile was treated with 2.9 g of 2,6-di-t-butyl-4-mercaptophenol and 0.2 ml of triethylamine catalyst. The reaction was carried out at ambient temperature with stirring and was completed in approximately one hour.
The solvent, acetonitrile, was removed under reduced pressure and a product of β-arylmercaptopropionate was collected. The β-arylmercaptopropionate was present as a thick oil with virtually no disulfide contaminant present.
EXAMPLE II
Reaction of 2,6-Di-t-butyl-4-mercaptophenol with Methyl Acrylate
A solution of 5.0 g (21.0 mmol.) of 2,6-di-t-butyl-4-mercaptophenol and 10 ml of acetonitrile was treated at room temperature with 1.81 g (21.0 mmol.) of methyl acrylate and 68 mg (0.67 mmol.) of triethylamine. The reaction mixture was stirred at ambient temperature for 1.5 hours and then the solvent was removed under reduced pressure to yield 6.8 g of the desired product--β-arylmercaptopropionate (m.p. 63°-64.5° C.). The yield was essentially 100 percent and the degree of purity was confirmed by the correspondence of the melting point of the product collected with that reported in the literature (m.p. 63°-64.5° C., lit. 62°-63.5° C.). | An improved process for preparing derivatives of mercaptophenols containing nitrile, carbonyl, sulphone or ester groups characterized by reacting the components in a polar solvent with an amine catalyst. The catalyst can be removed from the product by co-distillation with the solvent to leave a relatively pure product free of contaminant without the need for further purification steps. The preferred amine catalysts are tertiary amines. | 2 |
1. FIELD OF THE INVENTION
[0001] The present invention relates generally to a mobile communication system employing a Broadband Wireless Access (BWA) scheme, and in particular, to an apparatus and method for performing a ranging operation in a BWA mobile communication system.
2. DESCRIPTION OF THE RELATED ART
[0002] In a 4 th generation ( 4 G) communication system which is a next generation communication system, active researches are being conducted on technology for providing users with services guaranteeing various qualities of service (QoSs) at a data rate of about 100 Mbps. The current 3 rd generation (3G) communication system generally supports a data rate of about 384 Kbps in an outdoor channel environment having a relatively poor channel environment, and supports a data rate of a maximum of 2 Mbps even in an indoor channel environment having a relatively good channel environment.
[0003] Meanwhile, a wireless local area network (LAN) system and a wireless metropolitan area network (MAN) system generally support a data rate of 20 Mbps to 50 Mbps. Therefore, in the current 4G communication system, active researches are being carried out on a new communication system securing mobility and QoS for the wireless LAN system and the wireless MAN system supporting a relatively high data rate in order to support high-speed services that the 4G communication system aims to provide.
[0004] Due to its broad service coverage and high data rate, the wireless MAN system is suitable for high-speed communication services. However, because mobility of a user, or a subscriber station (SS), is not taken into consideration, handover caused by fast movement of the subscriber station is also not considered in the system. Therefore, an apparatus and scenario for supporting handover caused by fast movement of the subscriber station is being studied actively.
[0005] FIG. 1 is a diagram illustrating a configuration of an IEEE 802.16e communication system.
[0006] Referring to FIG. 1 , the IEEE 802.16e communication system has a multicell configuration, i.e., has a cell 100 and a cell 150 , and is comprised of a base station (BS) 110 controlling the cell 100 , a base station 140 controlling the cell 150 , and a plurality of subscriber stations 111 , 113 , 130 , 151 and 153 . Transmission/reception between the base stations 110 and 140 and the subscriber stations 111 , 113 , 130 , 151 and 153 is achieved using an OFDM/OFDMA scheme. Among the subscriber stations 111 , 113 , 130 , 151 and 153 , the subscriber station 130 is located in a boundary area, or a handover area, of the cell 100 and the cell 150 . Therefore, it is necessary to support handover for the subscriber station 130 in order to support mobility of the subscriber station 130 .
[0007] The wireless MAN system is a Broadband Wireless Access (BWA) communication system, and a system employing an Orthogonal Frequency Division Multiplexing (OFDM) scheme and an Orthogonal Frequency Division Multiplexing Access (OFDMA) scheme to support a broadband transmission network for a physical channel of the wireless LAN system is called an IEEE 802.16a communication system. The IEEE 802.16a communication system is a broadband wireless access communication system employing OFDM/OFDMA scheme. Because the IEEE 802.16a communication system applies the OFDM/OFDMA scheme to the wireless MAN system, it can support high-speed data transmission by transmitting a physical channel signal using a plurality of sub-carriers.
[0008] Meanwhile, the IEEE 802.16e communication system is a system designed to consider mobility of subscriber stations in the IEEE 802.16a communication system. In conclusion, both the IEEE 802.16a communication system and the IEEE 802.16e communication system are a broadband wireless access communication system using the OFDM/OFDMA scheme.
[0009] A description will now be made of rangings, including Initial Ranging, Maintenance Ranging (or Periodic Ranging), and Bandwidth Request Ranging, all of which are used in the IEEE 802.16a communication system.
[0010] First, the initial ranging will be described.
[0011] The initial ranging is performed to acquire synchronization with a subscriber station by a base station. The initial ranging is performed to adjust a correct offset between the subscriber station and the base station and to control transmission power. That is, the subscriber station receives a DL_MAP message and a UL_MAP message upon power on to acquire synchronization with the base station, and then performs the initial ranging in order to adjust the time offset with the base station and transmission power. Because the IEEE 802.16a communicant system uses the OFDM/OFDMA scheme, sub-channels and ranging codes are required for the ranging procedure, and a base station assigns available ranging codes according to an object, or a type, of the rangings. This will be described in detail herein below.
[0012] The ranging code is generated by segmenting a pseudo-random noise (PN) sequence having a length of, for example, 2 15 −1 bits into predetermined units. Generally, two ranging sub-channels having a length of 53 bits constitute one ranging channel, and a PN code is segmented through a ranging channel having a length of 106 bits to generate ranging codes. Of the formed ranging codes, a maximum of 48 ranging codes RC# 1 to RC# 48 can be assigned to subscriber stations, and as a default value, a minimum of 2 ranging codes per subscriber station are applied to the rangings of the 3 objects, i.e., initial ranging, periodic ranging and bandwidth request ranging. In this way, different ranging codes are assigned to the rangings of the 3 objects. For example, N ranging codes are assigned for the initial ranging (N RCs (Ranging Codes) for initial ranging), M ranging codes are assigned for the periodic ranging (M RCs for maintenance ranging), and L ranging codes are assigned for bandwidth request ranging (L RCs for BW-request ranging). The assigned ranging codes, as described above, are transmitted to subscriber stations through a DL_MAP message, and the subscriber stations perform a ranging procedure by using ranging codes included in the DL_MAP message according to their objects.
[0013] Second, the periodic ranging will be described.
[0014] The periodic ranging represents ranging periodically performed to adjust a channel status with a base station by a subscriber station that adjusted a time offset with the base station and transmission power through the initial ranging. The subscriber station performs the periodic ranging using ranging codes assigned for the periodic ranging.
[0015] Third, the bandwidth request ranging will be described.
[0016] The bandwidth request ranging is ranging used to request bandwidth assignment to actually perform communication with a base station by a subscriber station that adjusted a time offset with the base station and transmission power through the initial ranging.
[0017] Meanwhile, the DL_MAP message is periodically broadcasted from a base station to all subscriber stations. When a subscriber station continuously receives the DL_MAP message, it is said that the subscriber station is synchronized with the base station. That is, subscriber stations receiving the DL_MAP message can receive all messages transmitted over a forward link.
[0018] When a subscriber station fails to access the base station, the base station transmits a UCD message including information indicating an available backoff value to the subscriber station.
[0019] When the ranging is performed, the subscriber station transmits a RNG_REQ message to the base station, and the base station receiving the RNG_REQ message transmits to the subscriber station an RNG_RSP message including information for correcting the above-mentioned frequency, time and transmission power.
[0020] As described above, the IEEE 802.16a communication system considers only a state in which a current subscriber station is fixed, i.e., mobility of the subscriber station is not considered, and a single-cell configuration. However, as described above, the IEEE 802.16e communication system is specified as a system that considers mobility of a subscriber station in the IEEE 802.16a communication system. Therefore, the IEEE 802.16e communication system must consider mobility of a subscriber station in a multicell environment. In order to provide mobility of a subscriber station in a multicell environment, modification of operations of the subscriber station and the base station is necessarily needed. In particular, in order to support mobility of the subscriber station, active research is being conducted on handover of the subscriber station considering the multicell environment.
[0021] In a broadband wireless mobile communication system, a subscriber station receives preambles transmitted from a plurality of base stations. The subscriber station measures CINRs of the received preambles. The subscriber station selects a base station having the highest CINR among the measured CINRs. That is, the subscriber station selects a base station having the best reception condition among a plurality of base stations transmitting preamble channels, thereby detecting its base station. Herein, a base station having the best reception condition, selected by the subscriber station, is called a “serving base station.”
[0022] The serving base station transmits a neighbor base station advertisement (MOB_NBR_ADV) message to the subscriber station.
[0023] The MOB_NBR_ADV message includes a plurality of IEs, such as Management Message Type representing a type of a transmission message, Configuration Change Count representing the number of changes in configuration, N_NEIGHBORS representing the number of neighbor base stations, Neighbor BS-ID representing an identifiers (ID) of each of the neighbor base stations, Physical Frequency representing a physical channel frequency of the neighbor base station, and TLV Encoded Neighbor Information representing other information related to the neighbor base station. In addition, the MOB_NBR_ADV message includes Hysteresis threshold representing a reference CINR based on which a subscriber station can request handover, and MAHO report period information for periodic scanning report.
[0024] A subscriber station receiving the MOB_NBR_ADV message transmits a Scanning Interval Allocation Request (MOB_SCN_REQ) message to the serving base station when the subscriber station desires to scan CINRs of preamble signals transmitted from neighbor base stations. A time at which the subscriber station requests scanning is not directly related to an operation of scanning CINR of the preamble signal, so a detailed description thereof will be omitted.
[0025] The MOB_SCN_REQ message includes a plurality of IEs, such as Management Message Type representing a type of a transmission message, and Scan Duration representing scanning duration for which the subscriber station desires to scan CINRs of preamble signals transmitted from the neighbor base stations. The Scan Duration is formed on a frame basis. The Management Message Type in which the MOB_SCN_REQ message is to be transmitted has not been defined yet (Management Message Type=undefined).
[0026] A serving base station receiving the MOB_SCN_REQ message transmits to the subscriber station a MOB_SCN_RSP message including information to be scanned by the subscriber station.
[0027] The MOB_SCN_RSP message includes a plurality of IEs, such as Management Message Type representing a type of a transmission message, connection ID (CID) of a subscriber station that transmitted the MOB_SCN_REQ message, and Scan Duration.
[0028] The Management Message Type in which the MOB_SCN_RSP message is to be transmitted has not been defined yet (Management Message Type=undefined), and the Scan Duration represents duration for which the subscriber station performs pilot CINR scanning.
[0029] Upon receiving the MOB_SCN_RSP message including scanning information, a subscriber station scans CINRs for neighbor base stations detected through the MOB_NBR_ADV message according to the scanning information parameters.
[0030] In the IEEE 802.16e communication system, in order to support handover, a subscriber station must measure CINRs of preamble signals transmitted from its neighbor base stations and its current base station, i.e., a serving base station, and if CINR of a preamble signal transmitted from the serving base station is lower than CINRs of preamble signals transmitted from the neighbor base stations, the subscriber station sends a handover request to the active base station.
[0031] As described above, in a wireless communication system, information is exchanged between a plurality of subscriber stations and base stations. A communication 30 system allowing a plurality of the subscriber stations to randomly access a base station supports at least one reverse common access channel.
[0032] That is, when the subscriber station intends to access the base station, the subscriber station initializes an access request in a selected reverse common access 35 channel. In this case, the base station acquires access request information from the subscriber station by detection in the reverse common access channel.
[0033] Due to an access environment provided by a reverse common access channel for media sharing, a subscriber station needs to adopt an appropriate random access method for avoiding or reducing collision between access requests from different subscriber stations.
[0034] The random access method is divided into an Additive Links Online Hawaii Area (ALOHA) method for detecting a channel before transmitting packet, and a slot ALOHA method for not performing channel detection before packet transmission.
[0035] Generally, the slot ALOHA technology for not detecting access requests from other subscriber stations before packet transmission cannot avoid collision between access requests from different subscriber stations. In such ALOHA technology, if it is determined that an access request from a subscriber station is collided, the access request from the subscriber station is reinitialized. In the re-initialization process, an access request occurring at a time after a backoff calculated and determined by a backoff algorithm is reinitialized.
[0036] The ALOHA technology is simple in its design because less inter-system control message requests occur in the system, but collision occurs between access requests from subscriber stations. For this reason, the ALOHA technology is applied to a system in an optical traffic environment where collision between access requests scarcely occurs.
[0037] Carrier Sense Multiple Access (CSMA) technology, a different random access method, requires channel detection before packet transmission. The CSMA protocol technology is different from the ALOHA technology in that it needs channel detection before packet transmission. Though the channel detection, the CSMA technology can further reduce collision compared with the ALOHA technology, thereby providing better traffic. However, as the CSMA protocol technology first performs channel detection, message requests increase according thereto, and the increase in message request increases complexity of system design and requires a control technology such as the channel detection, causing an increase in cost.
[0038] The ALOHA protocol, a random protocol well known in the communication network field, was originally studied by several researchers in University of Hawaii to connect multiple wireless packet terminals to each other. The ALOHA and slot ALOHA structure-based technology is suitable for an optical traffic environment, and is simple in design because it needs less system information.
[0039] The ALOHA technology has been popularly used in a wireless communication system. For example, the ALOHA technology has been applied to the IEEE 802.16a communication system which is a broadband wireless access communication system using a frequency between 2 and 11 GHz.
[0040] The IEEE 802.16a technology chiefly aims at providing fixed broadband access technology. The IEEE 802.16a technology provides three operation modes: single carrier, OFDM, and OFDMA modes.
[0041] The single carrier and OFDM operation modes initialize access request in a reverse access channel by a message request from a media access control (MAC) layer of a subscriber station. However, the OFDMA operation mode needs pseudo-random code information for performing access request by the subscriber station.
[0042] According to the IEEE 802.16a technology, when a subscriber station needs to access a network, the subscriber station performs a network entering procedure that should be performed under mutual cooperation between the subscriber station and the base station in the IEEE 802.16a technology. A brief description of the network entering procedure included in the IEEE 802.16a technology will now be made below.
[0043] The subscriber station includes channel assignment information for a reverse channel and a forward channel detected in a forward control channel transmitted from a base station, and performs synchronization with the base station. The subscriber station operates in cooperation with a network that performs an initial ranging procedure. The subscriber station negotiates with a network including such information as system service capacity of the subscriber station, authentication, and a registration step. Further, the subscriber station installs session connection and other operations. The network entering procedure is provided for a subscriber station using a random access method similar to the ALOHA protocol during the initial ranging measurement procedure. Thereafter, when the subscriber station fails to perform correct access request from the base station due to collision, the subscriber station performs a backoff procedure.
[0044] The backoff procedure will be described in detail herein below.
[0045] When backoff occurs due to interruption of access request, a backoff time is calculated by a backoff algorithm previously designated on a backoff domain. For the backoff time calculated in this manner, the subscriber station suffers delay. When the backoff time expires, the subscriber station reinitializes information for entering a network through another access request.
[0046] Assignment information of the backoff domain is periodically provided by a system for subscriber stations within a common control channel. Commonly, various backoff time assignments and backoff algorithms are provided to enable all users to fairly access a system.
[0047] Meanwhile, in a multicell mobile communication system, inevitable mobility of a subscriber station brings about a call discontinuity problem during handover. This provides how to maintain a session when a subscriber station is located in an area where multiple cells overlap each other. Such a problem can be resolved by a hard handover method.
[0048] The hard handover procedure will now be described herein below.
[0049] A subscriber station first disconnects connection pre-connected to a base station for the hard handover time. Thereafter, the subscriber station accesses again the network system and establishes connection with a newly selected base station within a time period for which it is considered that the subscriber station can receive a service from the system. IEEE 802.16e was extended from IEEE 802.16a in order to support mobility of subscriber stations, and the IEEE 802.16e is so designed as to include IEEE 802.16a technology in order to provide fixed connection to the subscriber stations.
[0050] In the IEEE 802.16e, the hard handover method is performed through a method for initializing an access request for selecting a new base station by a subscriber station. In addition, a network entering procedure for maintaining compatibility with IEEE 802.16a is equal to a network entering procedure of IEEE 802.16a. In such a network entering procedure, a subscriber station first acquires channel assignment information for a reverse channel and a forward channel, detected from a forward control channel. Next, the subscriber station enters a corresponding network as it acquires synchronization with a base station.
[0051] The subscriber station operates in cooperation with a connection procedure of a newly selected base station. Here, the connection procedure includes performing partial authentication and subscriber station registration, and re-establishing session connection.
[0052] A description will now be made of a difference between handover in an initial ranging procedure of a subscriber station and handover requested by a network access procedure.
[0053] First, the handover in the network access procedure aims at continuously maintaining a session requesting an access service of a subscriber station, generally determined within a short time period. However, the handover in the initial ranging procedure of a subscriber station aims at making a network the subscriber station first accesses. Accordingly, in some cases, a maximum access delay of the subscriber station is shorter than a handover time for initial ranging of the subscriber station. Therefore, the initial ranging procedure of a subscriber station needs to make a handover time for network access to go in advance of that in the general initial ranging procedure of a subscriber station. However, in terms of a service provided to allow subscriber stations to fairly access a system, aimed by the IEEE 802.16a technology, an access request for averagely performing an access procedure for allowing all subscriber stations to enter the network must be made. In this case, for example, an actual IEEE 802.16a access service method is used in a common access channel disadvantageously. More specifically, a request for faster handover necessary for network access increases an access time for handover, causing the huge amount of collisions between handover access requests and other access requests. As a result, such a request cannot satisfy a fast access request for handover.
[0054] Further, in case of IEEE 802.16a having various access service requests for rapidly entering a network requested by the handover, a possible structure for a network entering procedure adopted by IEEE 802.16a provides an access channel assigned for an access request for handover by the system. However, this method assigns network resource such as bandwidth, causing an unnecessary waste of resource.
[0055] In conclusion, a difference between the network entering procedure requested by handover and the initial ranging procedure requested by handover is as follows.
[0056] First, the network entering procedure requested by handover establishes connection between a subscriber station and a base station before handover occurs. Next, the subscriber station previously includes system information such as appropriate service capability of the system and a system time.
[0057] In order to improve handover efficiency, the network entering procedure requested by handover can disregard or skip several steps predefined in IEEE 802.16a.
[0058] Moreover, in order to simplify a particular network entering step for handover and provide a fast access service requested by handover, it is necessary to provide a method for defining access request information by the system during handover.
SUMMARY OF THE INVENTION
[0059] It is, therefore, an object of the present invention to provide a method for defining a network access request during a handover time and supporting multilevel access service in a system using a common access channel for performing an access request service.
[0060] It is another object of the present invention to provide a method that can be conveniently used by IEEE 802.16e describing a handover request for fast network access using a common access channel.
[0061] It is further another object of the present invention to provide a method for supporting a system providing, on an on-demand basis or periodically, assignment information for each access channel corresponding to a multiple backoff domain and common access channel information of a subscriber station, and supporting multilevel access services using a common access channel, in order to avoid collision between an operation of calculating an access request capable of selecting a backoff domain by a subscriber station according to access type and an operation of determining a time for reinitializing an access request from a corresponding backoff domain, in a system based on ALOHA or slot ALOHA technology.
[0062] It is yet another object of the present invention to provide an access service having at least two levels using the above method.
[0063] The above and other objects are achieved by providing a method for performing a ranging operation by a subscriber station in a mobile communication system using a broadband wireless access scheme, the method comprising the steps of receiving, from a base station, backoff domains having a backoff start point and a backoff end point for each of rangings, determined according to priority levels of the rangings between the base station and subscriber stations; performing a ranging operation with the base station, and selecting a backoff domain corresponding to a priority level of the performed ranging among the received backoff domains if the ranging fails; and re-performing a ranging operation with the base station according to the selected backoff domain.
[0064] The priority level is determined according to a service quality level of data provided to the subscriber stations and whether handover of the subscriber stations is performed.
[0065] The step of re-performing a ranging operation with the base station according to the selected backoff domain comprises the step of re-performing a ranging operation with the base station at a particular time between the back start point and the backoff end point for the selected backoff domain.
[0066] The backoff domains are determined so that a time period occupied by a backoff domain having a highest priority level becomes a shortest time period and a time period occupied by a backoff domain having a high priority level is shorter than a time period occupied by a backoff domain having a low priority level.
[0067] The above and other objects are achieved by providing a method for performing handover for an access service on a common access channel in a mobile communication system using a broadband wireless access scheme, the method comprising the steps of: receiving backoff domains having a backoff start point and a backoff end point for each of subscriber stations, when handover between a base station and the subscriber stations is performed; checking the received backoff domains, and selecting a backoff domain for handover among the backoff domains; and determining a backoff value corresponding to the selected backoff domain, and re-requesting ranging after waiting for the determined backoff value.
[0068] The above and other objects are achieved by providing a method for transmitting backoff values used for rangings between a base station and subscriber stations in a mobile communication system using a broadband wireless access scheme, the method comprising the steps of: determining backoff domains having a backoff start point and a backoff end point according to a priority level of each of the rangings, for each of the rangings; and transmitting the backoff domains determined for each of the rangings to the subscriber stations.
[0069] The step of determining backoff domains according to a priority level of each of the rangings comprises the step of determining the backoff domains so that a time period occupied by a backoff domain having a highest priority level becomes a shortest time period and a time period occupied by a backoff domain having a high priority level is shorter than a time period occupied by a backoff domain having a low priority level.
[0070] The above and other objects are achieved by providing a method for performing a ranging operation in a mobile communication system using a broadband wireless access scheme, the method comprising the steps of: periodically receiving by a subscriber station a broadcasting message and uplink channel information (UL-MAP) from a base station by detecting on a common control channel; randomly selecting an access channel to be accessed through the uplink channel information, and then transmitting a ranging request message for an access in the selected access channel; comparing the number of retransmissions of the request message with a predefined value, if reception of a response message from the base station exceeds a response waiting time; comparing the number of retransmissions with an allowable access processing time if the number of retransmissions is smaller than the predefined value; selecting a backoff domain according to a priority level of a service level if the number of retransmissions does not exceed the allowable access processing time; and selecting a backoff value and calculating a backoff time from the selected backoff domain, and re-transmitting a ranging request message in the access channel if the calculated backoff time has passed.
[0071] The above and other objects are achieved by providing a handover apparatus for providing an access service on a common access channel in a mobile communication system, the apparatus comprising a subscriber station that requests ranging as it enters a network for handover; and a base station that transmits handover information to the subscriber station; wherein when the subscriber station requests ranging as it enters the network for handover, the subscriber station receives backoff start information and backoff end information from the base station and determines a backoff value for handover according to the received backoff start information and backoff end information.
[0072] The subscriber station re-requests ranging to the base station after waiting for the determined backoff value when the ranging fails.
[0073] The above and other objects are achieved by providing an apparatus for performing a ranging operation in a mobile communication system using a broadband wireless access scheme, the apparatus comprising a subscriber station for receiving and selecting, from a base station, backoff domains having a backoff start point and a backoff end point for each of rangings determined according to a priority level. If the subscriber station fails to perform ranging, the subscriber station selects a backoff domain corresponding to a priority level of the ranging among the received backoff domains and re-performs a ranging operation with the base station according to the selected backoff domain.
[0074] The above and other objects are achieved by providing an apparatus for performing an apparatus for transmitting backoff values used for rangings of subscriber stations in a mobile communication system using a broadband wireless access scheme, the apparatus comprising a base station for determining backoff domains having a backoff start point and a backoff end point according to a priority level of each of rangings, for each of the rangings, and transmitting the backoff domains determined for each of the rangings to the subscriber stations.
BRIEF DESCRIPTION OF THE DRAWINGS
[0075] FIG. 1 is a diagram illustrating a configuration of a general IEEE 802.16e communication system;
[0076] FIG. 2 is a diagram illustrating a method for assigning forward and reverse channels according to an embodiment of the present invention;
[0077] FIG. 3 is a diagram illustrating frame control information and a channel mapping method for TDD according to an embodiment of the present invention;
[0078] FIG. 4 is a diagram illustrating frame control information and a channel mapping method for FDD according to an embodiment of the present invention;
[0079] FIG. 5 is a diagram illustrating a multiple backoff domain individually corresponding to each access channel and two mapping formats of a multiple access channel according to an embodiment of the present invention;
[0080] FIG. 6 is a diagram illustrating a format of an access request message used for handover according to an embodiment of the present invention;
[0081] FIG. 7 is a diagram illustrating a procedure for processing ranging when hard handover occurs according to an embodiment of the present invention; and
[0082] FIG. 8 is a diagram illustrating an access request procedure by a subscriber station according to an embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0083] A preferred embodiment of the present invention will now be described in detail with reference to the annexed drawings. In the following description, a detailed description of known functions and configurations incorporated herein has been omitted for conciseness.
[0084] Before a detailed description of the present invention is given, it should be noted that a base station performs broadcasting though a UCD message so that it can adjust a backoff value which is a waiting time until the next re-request, when subscriber stations fail to request ranging. For example, when a subscriber station fails to request ranging during handover, the subscriber station is allowed to select a backoff time of a previous time having a higher priority level, thereby enabling fast handover.
[0085] The present invention provides a method for defining a network access request for handover and providing a multilevel access service in a system using a common access service for performing an access service. This can be conveniently used by IEEE 802.16e technology that supplements a request for a fast network access service required by handover using a common access channel.
[0086] With reference to FIG. 2 , a description will now be made of a method for assigning forward and reverse channels according to an embodiment of the present invention.
[0087] FIG. 2 is a diagram illustrating a method for assigning forward and reverse channels according to an embodiment of the present invention.
[0088] In a wireless communication system such as a broadband wireless access system defined by IEEE 802.16e technology, mutual information between a subscriber station and a base station is transmitted over a multiple logical channel. According to a transmission direction of data information, the logical channel can be divided into a forward channel transmitted from a base station to a subscriber station, and a reverse channel transmitted from a subscriber station to a base station.
[0089] Referring to FIG. 2 , a forward channel between a subscriber station (SS) 12 and a base station (BS) 11 includes a forward pilot channel (F-PCH), a forward common control channel (F-CCH), and a forward traffic channel (F-TrCH).
[0090] The forward pilot channel is used for synchronization between the subscriber station 12 and the base station 11 . The forward common control channel is used for transmitting common control information and a network parameter transmitted from the base station 11 to the subscriber station 12 . The common control information includes channel assignment information for reverse and forward channels. Finally, the forward traffic channel is used for transmitting forward traffic information transmitted from the base station 11 to the subscriber station 12 .
[0091] Next, a reverse channel between the base station 11 and the subscriber station 12 includes a reverse access channel (R_ACH) and a reverse traffic channel (R-TrCH).
[0092] The reverse access channel is used for an access service of the subscriber station 12 , and the reverse traffic channel is used for transmitting reverse traffic information transmitted from the subscriber station 12 to the base station 11 .
[0093] When a subscriber station intends to access a system in a wireless environment, the subscriber station should trace information from a forward pilot channel and complete a synchronization process with a base station on a downlink, which can be performed by capturing. The subscriber station also needs a process of acquiring common control information and a network parameter transmitted over a forward 5 common control channel. The common control information includes channel assignment information for reverse and forward channels as well as parameter information related to each channel, and the subscriber station can initialize an access request in a selected access channel based on the information.
[0094] With reference to FIG. 3 , a description will now be made of frame formats of a downlink transmission signal and an uplink transmission signal in a time domain.
[0095] FIG. 3 is a diagram illustrating frame control information and a channel mapping method according to an embodiment of the present invention. Specifically, FIG. 3A is a diagram illustrating frame control information for a TDD mode and a channel mapping method according to a first embodiment of the present invention, and FIG. 3B is a diagram illustrating frame control information for the TDD mode and a channel mapping method according to a second embodiment of the present invention.
[0096] Referring to FIG. 3 , frame control information 22 for a TDD mode is transmitted from a subscriber station 11 to a subscriber station over a forward control channel including mapping information of a downlink channel and an uplink channel. The downlink channel information, as shown in FIGS. 2A and 2B , reflects an assignment position of a downlink subframe 24 on a downlink channel. The uplink channel information reflects an assignment position of an uplink subframe 26 on an uplink channel.
[0097] Because it takes a certain time in defining assignment information of the uplink frame 26 on an uplink channel from a base station that starts transmitting the uplink information before transmitting the assignment information to the subscriber station, a system is needed in which a transmission time interval of a particular frame is longer than two times the maximum transmission delay of a signal transmitted from the base station to the subscriber station. In FIG. 3A , uplink channel information of a particular frame includes an assignment position of the same frame after a time period on an uplink channel.
[0098] FIG. 4 is a diagram illustrating frame control information and a channel mapping method according to an embodiment of the present invention. Specifically, FIG. 4A is a diagram illustrating frame control information for an FDD mode and a channel mapping method according to a first embodiment of the present invention, and FIG. 4B is a diagram illustrating frame control information for the FDD mode and a channel mapping method according to a second embodiment of the present invention.
[0099] Referring to FIG. 4 , the FDD mode described below has a similar operation to that of the TDD mode of FIG. 4 . That is, frame control information 32 can be transmitted from a base station 11 to a subscriber station 12 over a forward control channel for the FDD mode. The frame control information 32 includes mapping information for a downlink channel and an uplink channel. Further, the downlink channel information reflects an assignment position of a downlink subframe 34 on a downlink channel, and the uplink channel information reflects an assignment position of an uplink subframe 36 on an uplink channel.
[0100] In FIG. 4A , particular uplink channel information includes an assignment position of the same frame after a time period on an uplink channel. In addition, a base 20 station receiving uplink or downlink broadcasting help can transmit parameter information on at least one channel defined for an access request of a subscriber station.
[0101] Meanwhile, it is necessary to invent a system for notifying multiple backoff domain assignment on an access channel to a subscriber station having separation information of a common access channel as well as information on a multiple backoff domain corresponding to each access channel.
[0102] A process of assigning a multiple backoff domain on an access channel will be described below with reference to FIG. 5 .
[0103] FIG. 5 is a diagram illustrating a multiple backoff domain individually corresponding to each access channel and two mapping formats of a multiple access channel according to an embodiment of the present invention. Specifically, FIG. 5A is a diagram illustrating an example of a mapping format of an uplink access channel for providing a multiple backoff domain, and FIG. 5B is a diagram illustrating another example of a mapping format of an uplink access channel for providing a multiple backoff domain.
[0104] As illustrated in FIG. 5 , an uplink reverse access channel (UL-RACH-MAP) 400 represents other combined downlink broadcasting information or a parameter corresponding to an access channel on an uplink channel. A format of the uplink reverse access channel 400 represents positions of M backoff domains and N uplink access channels corresponding to each uplink access channel.
[0105] Referring to FIG. 5A , a parameter corresponding to each uplink access channel includes at least one uplink channel ID and backoff start values and backoff end values of M backoff domains. A parameter corresponding to an uplink (reverse) access channel having an ID# 1 includes not only an uplink channel ID# 1 4102 , but also parameters defining M backoff domains.
[0106] The parameters of the M backoff domains are as follows.
[0107] That is, the parameters include parameters defining a first backoff domain, such as a backoff end value # 1 4106 and a backoff start value # 1 4104 of the first backoff domain, among values for an M th backoff domain, such as a sequential backoff start value #M 4108 and a backoff end value #M 4110 of the M th backoff domain.
[0108] The format of the uplink reverse access channel 400 also needs to represent assignment positions of parameters for other (N−1) uplink channels. An assignment format of parameters for each access channel is similar to that of an access channel having the ID# 1 . For example, an assignment format for N access channels includes different parameter fields 4114 to 4120 of M backoff domains, and an N th access channel's ID (uplink channel D#N) 4112 .
[0109] A brief description will now be made of the handover ranging start value and the handover ranging end value.
[0110] That is, the handover ranging start value and the handover ranging end value include HO_ranging_start representing a start point of backoff using initial ranging, i.e., representing an initial backoff window size for initial ranging performed on a subscriber station during a handover processing time, and HO_ranging_end representing a final backoff window size for initial ranging performed on the subscriber station during the handover processing time. The highest order bits of the HO_ranging_start should not be used, and their value is set to ‘0’. Also, the highest order bits of the HO_ranging_end should not be used, and their value is also set to ‘0’. The backoff value represents a kind of a waiting time value for which subscriber stations should wait when they fail to request ranging. At this moment, the base station transmits to the subscriber station the backoff value which is time information for which the subscriber station should wait for the next ranging when it fails to perform ranging.
[0111] Next, referring to FIG. 5B , parameters corresponding to each uplink channel include not only at least one uplink channel ID but also a backoff start value # 1 of a first backoff domain and a backoff end value of every back-off domain corresponding to each uplink access channel ID.
[0112] Parameters corresponding to the uplink (reverse) access channel having an ID# 1 include not only parameters defining M backoff domains but also an uplink channel ID# 1 4202 .
[0113] The parameters of the M backoff domains are as follows.
[0114] The M backoff domains include parameters that define a first backoff domain having a backoff end value # 1 4206 and a backoff start value # 1 4204 of an individual first backoff domain.
[0115] A start value of a second backoff domain can be obtained from an end value # 1 of a backoff domain for the first backoff domain. Accordingly, end values of respective backoff domains need declaration from a backoff end value # 2 4208 to a backoff end value #M 4210 .
[0116] Meanwhile, in a format of the uplink reverse access channel 400 , an assignment format for parameters of other (N−1) access channels is similar to that of parameters for an access channel having an ID# 1 . For example, N access channels have an uplink channel ID#N of an N th access channel, and include parameter fields 4214 to 4220 for M backoff domains.
[0117] A description will now be made of a backoff algorithm for multilevel access services.
[0118] The multilevel backoff algorithm is used for providing multilevel access services on a common access channel, and the multilevel backoff algorithm includes a backoff algorithm on the ALOHA technology. That is, the multilevel backoff algorithm selects a backoff value on a domain selected by including the backoff algorithm of the ALOHA technology and selects a backoff domain according to an access type. An exponential backoff algorithm is popularly used in the ALOHA technology. Such an algorithm is used in, for example, IEEE 802.16a.
[0119] The multilevel backoff algorithm will be described with reference to a 2-level backoff domain.
[0120] A subscriber station 12 acquires information on a reverse access channel related to assignment information of a 2-level backoff domain on an access channel corresponding to assignment information of the 2-level backoff domain by detection in a forward common control channel. Such a 2-level backoff domain is defined as [0,β] and [β+1,γ] of M having two values of two backoff domains corresponding to a particular access channel, in the format of the uplink reverse access channel 400 . Both of the γ (γ>β) and the β have a positive integer value. Such an access channel provides two types of access services including a common access service and a fast access service. Such two types of access services are provided by two selected domains [0,2 β ] and [2 β +1,2 γ ] that use a binary exponential backoff algorithm. For example, when a subscriber station needs a common access service, a backoff domain time is randomly selected from the second backoff domain [2 β +1,2 γ ]. In addition, when the subscriber station needs a fast access service, a backoff time is randomly selected from the first backoff domain [0,2 β ].
[0121] Values of the γ and the β are selectively determined according to the number of subscriber stations and service execution. That is, the selection of γ and β should satisfy execution requests related to a fast access service, such as a collision rate between access requests and a parameter of an allowable access time. In addition, the selection of γ and β should consider a collision rate between fast access requests and common access requests and parameters for an allowable access time of the common access service. Commonly, it is guaranteed that the fast access service has a shorter access service time than the common access service.
[0122] Meanwhile, the multilevel backoff algorithm proposed in the present invention can be easily extended even when the M is larger than 2. That is, compared with a general exponential backoff algorithm, the multilevel backoff algorithm is advantageous in that it is easy to separate different types of access services and easy to relieve collision of access requests between a 2-level access service provided on a common access channel by separation of a backoff domain and other types of access services. Furthermore, compared with a method for providing a common access channel for another type of an access request, the multilevel backoff algorithm can save network resource and bandwidth. The multilevel backoff algorithm can be easily developed in IEEE 802.16e in order to satisfy requests that provide a fast access for hard handover using a common access channel.
[0123] A description will now be made of a method for defining a network access request for handover on a common access channel and providing a multilevel access service.
[0124] A subscriber station can obtain access information corresponding to each access channel by detecting other uplink broadcasting information and an uplink channel. In using common access channel for accessing a communication system and receiving a service, the subscriber station can initialize an access request to a selected base station on a common access channel. During a period for which a multilevel access service is provided on the common access channel, a communication system needs to cooperate with the subscriber station. Accordingly, the communication system can effectively provide a service corresponding to a request of the subscriber station and define an access request of the subscriber station.
[0125] A method for providing a multilevel access service on a common access channel will now be described together with an example of IEEE 802.16e.
[0126] The multilevel service includes processing a common access request initial value and handover. When the common access request initial value is considered, an access request for handover can be obtained by simplifying a network entering service.
[0127] In the method for providing a multilevel access service on a common access channel, a subscriber station first performs an operation of detecting an uplink broadcasting message.
[0128] That is, in order to provide a multilevel access service on a common access channel, a base station broadcasts, periodically or on an on-demand basis, channel assignment information of cells, including mapping information of a multiple backoff domain on an uplink reverse access channel corresponding to the request of a subscriber station and assignment information of an uplink channel. After completing synchronization with the base station on a downlink, the subscriber station acquires parameter information of an access channel by detecting other downlink broadcasting information or an uplink channel.
[0129] Next, the subscriber station performs transmission request initialization.
[0130] That is, the subscriber station can initialize an access request of a base station selected on a selected uplink access channel. In order to provide handover on a common access channel, compatibility with IEEE 802.16a, and a different type of an access service including an access initial value, the subscriber station adopts the above-stated multilevel backoff algorithm, and determines and calculates a backoff time of a selected backoff domain. Such a method is used for providing a service having at least two levels and easily relieving collision between types of different access requests.
[0131] For handover of a subscriber station on the common access channel, an access request message is required. For a system used in defining such an access request message, an IEEE 802.16a access request message such as RNG-REQ can be continuously used as an original access initial value of the subscriber station in order to provide another access service for another type of an access request, together with an example of an IEEE 802.16e specification. The access request message for handover can be an access request message using previously assigned pseudo-random code information, adding a field for defining a handover request on an initial RNG-REQ access request message, or having a handover request ID.
[0132] The type of the access request message will be described herein below.
[0133] The access request message includes an access request message type of a MAC layer. That is, an access request message for handover is an access request message including a field for defining a handover request, or can add a field for defining a handover request on an initial access request message RNG_REQ. For an OFDM operation mode or a single carrier on IEEE 802.16e, an access request for handover can use a previously assigned access request message. A format of the previously assigned access request message for handover will be described below with reference to FIG. 6 .
[0134] FIG. 6 is a diagram illustrating a format of an access request message used for handover according to an embodiment of the present invention.
[0135] Referring to FIG. 6 , a format of an access request message (REN-REQ-HO) 500 previously assigned for handover is illustrated. The previously assigned access request message includes a handover access request type ID 504 and a used uplink access channel ID 502 . The access request message for handover can be implemented by adding the handover request type ID 504 to an initial RNG-REQ access request message.
[0136] A pseudo-random code-based access request process for handover will be described below.
[0137] In a common access channel, a subscriber station can initialize a network access request message for handover by a pseudo-random code. The initialization process will be described below.
[0138] First, the pseudo-random code is generated.
[0139] Such a pseudo-random code is defined as one of three types of pseudo-random codes previously used by a request of a subscriber station in an OFDM scheme defined in IEEE 802.16a, and the three types include a network service for initial ranging, periodic ranging, and an individual bandwidth.
[0140] The three types of pseudo-random codes are generated from a generator polynomial of Equation (1), and have a long pseudo-random code type output value.
1+X 1 +X 4 +X 7 +X 15 (1)
[0141] A pseudo-random code used in the three types, i.e., initial ranging, periodic ranging and bandwidth request ranging, has an output value of a long pseudo-noise code, but a clock generated at each pseudo-random code has a different value. In case of default, a size of each pseudo-random code is 106 bits.
[0142] In order to simplify a network entering procedure requested by a system managing hard handover, an IEEE 802.16e OFDMA scheme uses a system defining a network access request for hard handover. For such a system, an access request message for hard handover defined by a pseudo-random code can be used. In addition, for compatibility with IEEE 802.16a and convenient system design, an H pseudo-random code is required by an access request for handover. Although generation of the H pseudo-random code has a result value of a long pseudo-random code, selection of a clock can have a different result value from the three types of pseudo-random codes.
[0143] A method for generating H pseudo-random codes requested by an access request for handover will now be described below.
[0144] An output value of a long pseudo-noise code occurring at an output of the generator polynomial of Equation (1), i.e., first N codes, are used for initial ranging, and 0 th to (106*N−1) th clocks are selected.
[0145] Next, M codes are used for periodic ranging, and (106*N) th to (106*(N+M)−1) th clocks are selected.
[0146] Next, L codes are used for bandwidth request ranging, and (106*(N+M)) th to (106*(N+M+L)−1) th clocks are selected.
[0147] Finally, H codes are used for an access request for hard handover, and (106*(N+M+L) th to (106*(N+M+L+H)−1) th clocks are selected.
[0148] The first N codes can be used for an access request for hard handover, the M codes can be used for initial ranging, the L codes can be used for periodic ranging, and the H codes can be used for bandwidth request ranging. In addition, each of the above codes can be arranged in several types.
[0149] A process of assigning the pseudo-random codes will be described herein below.
[0150] In order to make a system for defining an access request for hard handover, the H pseudo-random codes generated by a system can be generally assigned to each cell. Such a method for generating the H pseudo-random codes is equal to the method described above. When a particular subscriber station performs hard handover, pseudo-noise codes assigned by a base station newly selected for a fast access service are randomly used in each cell. Such an assignment method is simple in structure, and mutual messages exchanged between the subscriber station and the system are small in number, but its characteristic is poor in terms of mobility. Thus, this method is not suitable for irregularly distributed subscriber stations.
[0151] A system according to another embodiment of the present invention can dynamically assign H pseudo-random codes of cells at a request of the cells. Each cell sends, periodically or on an on-demand basis, identifiers or different signs on a forward common access channel. By detection on a common access channel, a subscriber station can acquire information on pseudo-noise codes assigned to a cell in a position of a newly selected base station. In this manner, it can be applied even to an environment where distribution of subscriber stations suffers irregular change. For example, a system can assign more pseudo-random codes to the cells having excessive handover traffic. Disadvantageously, however, the system must transmit assignment information of the pseudo-random codes periodically or on an on-demand basis.
[0152] A description will now be made of a MAC layer response message for an access request.
[0153] After correctly receiving an access request from a subscriber station, a base station assigns a unique connection identifier (CID) for the access request from the subscriber station. The base station handles the access request from the subscriber station by a handshake method. After receiving an RNG-REQ-HO or RNG-REQ access request message from the subscriber station, the base station checks a system capable of providing a service for initializing an access request by a subscriber station. When the system check is completed, the base station transmits an RNG-RSP access request response message to the subscriber station. Accordingly, the subscriber station includes information on the unique connection identifier CID set up for the access request.
[0154] A description will now be made of a method for providing a multilevel access service in a common access channel according to an embodiment of the present invention.
[0155] In IEEE 802.16e, when handover occurs, a subscriber station can initialize an access request of a newly selected base station. For compatibility with IEEE 802.16a, an access procedure of the subscriber station can maintain an IEEE 802.16a network entering procedure. An IEEE 802.16e network entering procedure, compared with the IEEE 802.16a network entering procedure, is advantageous in that a network entering procedure of a subscriber station for hard handover can be simply performed with several processes of exchanging information such as time and service capacity of the system.
[0156] The access procedure of a subscriber station for handover will be described herein below.
[0157] In the access procedure of a subscriber station for handover, the subscriber station first performs synchronization with the base station through detecting and tracing in a forward channel. Thereafter, the subscriber station acquires forward and reverse channel assignment information. In this case, the subscriber station operates in cooperation with a base station newly selected to perform access processing. Such an access procedure includes performing partial authentication and registration step of the subscriber station, and reestablishing session connection.
[0158] A ranging procedure including the occurrence of handover will now be described with reference to FIG. 7 .
[0159] FIG. 7 is a diagram illustrating a procedure for processing ranging when hard handover occurs according to an embodiment of the present invention. Specifically, FIG. 7A is a diagram illustrating a ranging procedure when IEEE 802.16e hard handover occurs, and FIG. 7B is a diagram illustrating a ranging procedure when OFDMA hard handover occurs. It can be understood herein that when hard handover occurs, the ranging procedure is easily compatible with an IEEE 802.16a initial ranging procedure.
[0160] Referring to FIG. 7A , at a time t 0 , a base station 11 broadcasts an uplink channel message of a cell on a common access request channel periodically or on ail on-demand basis.
[0161] At a time t 1 , a particular subscriber station on the cell receives the uplink channel message. The uplink channel message includes related parameters representing an uplink reverse access channel as an access channel for M=2 shown in FIG. 4 . In this way, the particular subscriber station selects an access channel.
[0162] At a time t 2 , the particular subscriber station initializes an RNG_REQ or RNG-REQ-HO access request to the base station on the selected access channel.
[0163] At a time t 3 , it is assumed that the base station receives an access request message. However, collisions occurring due to access request messages from other subscriber stations during the time t 3 may cause a loss of the access request messages. If the subscriber station fails to correctly receive an access request response message corresponding to the access request of the particular subscriber station from the base station after waiting for several time periods, it is determined that the access request fails. Then the subscriber station selects a corresponding backoff domain according to an access service type. For example, this selects a first backoff domain for handover and selects a second backoff domain for a common access request, and each subscriber station can calculate a backoff time with a multilevel backoff algorithm for a time t 2 at a time t 4 .
[0164] At the time t 4 , it is assumed that the subscriber station initializes an RNG-REQ or RNG-REQ-HO access request message.
[0165] At a time t 5 , the base station correctly receives the RNG-REQ or RNG-REQ-HO access request message form the subscriber station. The base station assigns an identifier for the access request and sends an access response message.
[0166] At a time t 6 , the response message includes ED information for the subscriber station, including several signs for response.
[0167] At a time t 7 , if the subscriber station has correctly received the RNG-RSP response message from the base station, the subscriber station initializes the RNG-REQ or RNG-REQ-HO access request message.
[0168] At a time t 8 , the base station should be informed that the subscriber station has correctly received transmission-related information from the base station. Accordingly, the subscriber station complies with a subscriber's request and transmits an identifier assigned by the base station.
[0169] At a time t 9 , while the base station receives the RNG-REQ or RNG-REQ-HO access request message from the subscriber station, it is determined whether the subscriber station has correctly received the response and the system continuously performs the next step.
[0170] Referring to FIG. 7B , a ranging procedure supporting occurrence of hard handover for an OFDMA mode in IEEE 802.16, proposed by the present invention, is illustrated. FIG. 8B is different from FIG. 7A in that an access request is completed by pseudo-random codes for ranging. In order to use a system for defining an access request for hard handover on a common access channel and simplify a network entering procedure at occurrence of hard handover, a subscriber station selects a previously assigned pseudo-random code to complete an access request on the common access channel. A cell assignment method and a pseudo-random code generation method are equal to the methods described above.
[0171] A procedure for implementing the ranging process by the subscriber station will be described herein below.
[0172] FIG. 8 is a diagram illustrating an access request procedure by a subscriber station according to an embodiment of the present invention.
[0173] Referring to FIG. 8 , a subscriber station periodically receives a broadcasting message from a base station on a common control channel by detection ( 702 ). If reception of the broadcasting message is not achieved for a time t 1 ( 704 ), the subscriber station detects an error and performs re-initialization ( 706 ). The t 1 means a maximum time required for receiving the broadcasting message.
[0174] Meanwhile, if the subscriber station normally receives a broadcasting message from the base station and receives uplink channel information UL-MAP within the time t 1 ( 708 ), the subscriber station acquires assignment information of an access channel group from the received uplink channel information. The subscriber station randomly selects an access channel from the access channel group and transmits an access request message RNG-REQ-HO or RNG-REQ in the selected access channel ( 712 ). A format of the RNG-REQ-HO has been described with reference to FIG. 5 . After transmitting the access request message, the subscriber station waits for a response message RNG-RSP from the base station ( 714 ).
[0175] If a time for which the subscriber station waits a response message RNG-RSP from the base station exceeds t 2 ( 716 ), the subscriber station compares the number of retransmissions with a predefined value ( 718 ). The t 2 represents a maximum time for which the subscriber station waits a response.
[0176] If the number of retransmissions is larger than the predefined value as a result of the comparison between the time for which the subscriber station waits a response message from the base station and the time t 2 , the subscriber station performs error indication and error processing ( 720 ). If the number of retransmissions is smaller than the predefined value as a result of the comparison, the subscriber station compares the number of retransmissions with an allowable access processing time ( 722 ). If the number of retransmissions exceeds the allowable access processing time, the subscriber station proceeds to step 720 and performs error processing ( 720 ). If the number of retransmissions does not exceed the allowable access processing time, the subscriber station selects a backoff domain according to a priority level of the service ( 724 ).
[0177] The priority level is selected at a start point and an end point of the backoff. For example, when hard handover occurs, the subscriber station selects a backoff domain according to a priority level of the hard handover.
[0178] After step 724 , the subscriber station selects a backoff value from a backoff domain selected by a multilevel backoff algorithm ( 726 ). When the selection of a backoff value is completed, the subscriber station waits for a calculated backoff time ( 728 ). When the backoff time expires, the subscriber station retransmits an RNG-REQ-HO or RNG-REQ message at the access channel described above (730), and then proceeds to step 714 where it waits for a next response message RNG-RSP.
[0179] However, if the subscriber station receives a response message RNG-RSP from the base station for the response message reception waiting time t 2 in step 714 , the subscriber station adjusts local parameters according to the response message RNG-RSP ( 732 ). Subsequently, the subscriber station determines whether the local parameters were correctly adjusted ( 734 ). When the adjusted parameters are not normal, the subscriber station performs error processing ( 740 ). However, when the adjusted parameters are normal, the subscriber station retransmits an access request message RNG-REQ-HO or RNG-REQ on the selected access channel ( 736 ). Thereafter, the subscriber station proceeds to a next step and performs a next process ( 738 ).
[0180] The RNG-REQ or RNG-REQ-HO message includes an identifier of a base station, assigned for the access request, and the access request means a base station where the subscriber station successfully receives related information transmitted by the base station.
[0181] While the invention has been shown and described with reference to a certain preferred embodiment thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.
EFFECTS OF THE INVENTION
[0182] According to the new method for providing multilevel access services in a common access channel, when subscriber stations fail ranging request, a backoff value representing a waiting time until a next re-request can be adjusted. That is, when ranging request fails during handover, a preceding backoff time having a high priority level is selected thereby enabling fast handover.
[0183] In addition, the present invention proposes a structure for defining a network access request for handover by using a common access channel to perform a multiple access request service, thereby reducing collisions occurring in a wireless communication system and saving network resource such as a bandwidth.
[0184] Further, the present invention can provide a fast access service for a subscriber station, being capable of contradicting a request for the fast access service by hard handover and simplifying a network entering procedure requested by a handover process.
[0185] Moreover, a system compatible with IEEE 802.16a technology is simply designed through a method for generating pseudo-random codes using the same polynomial generator, and a method for assigning binary pseudo-random codes is easy to design a system for defining an access request for hard handover. | The present invention relates to a method for performing a ranging operation according to the priority order in a mobile communication system using a BWA (Broadcast Wireless Access) scheme. The method according to the invention for performing a range operation by a subscriber terminal in a mobile communication system using the BWA (Broadcast Wireless Access) scheme comprises steps of: receiving backoff domains having the start and end values of the backoff corresponding to each ranging operation, the backoff domains being determined from a base station according to the priority order of the ranging operations between the base station and subscriber terminals; performing a ranging operation and, if it is determined that the step of performing the ranging operation fails, selecting backoff domains among the received backoff domains according to the priority order of the performed ranging operations; and, re-performing the ranging operation according to the selected backoff domains. | 7 |
[0001] This is a continuation of International Application No. PCT/PT2006/000021, filed Aug. 4, 2006, which claims priority to Portuguese Patent Application No. 103331, filed Aug. 5, 2005, all of which are hereby incorporated by reference.
OBJECT OF THE INVENTION
[0002] The present invention refers to the modified yeast, preferably Saccharomyces cerevisiae , with the introduction of a novel gene corresponding to an active transporter for xylose. It is also object of the present invention the co-transport of xylose/proton by yeasts in the presence of glucose. Another object of the present invention is the use of recombinant yeasts, with the same xylose transporting system, in the fermentation of lignocellulosic hydrolysates.
[0003] The object of the present invention is to provide to the bioethanol fuel industry yeasts capable of assimilating faster xylose in glucose mixtures and to ferment xylose more efficiently and with higher specific productivity.
STATE OF THE ART
[0004] Action programmes worldwide target to the production of biofuels, with relevance to bioethanol, as an alternative and renewable energy. Those measures aim to reduce the dependency on petroleum and to reduce the emission of gases and the resulting climatic changes. At present, crops and other substrates from agricultural origin rich in glucose are used in the industrial production of ethanol by the yeast Saccharomyces cerevisiae . The lignocellulosic materials are the most abundant components of plant biomass. They make up the major forest product and a considerable fraction of waste resulting from agricultural practice. The development of processes for its bioconversion into ethanol is potentially important and strongly stimulated.
[0005] Cellulose in lignocellulosic materials is a polymer exclusively formed by glucose, whilst the hemicelluloses fraction is composed of polymers containing a mixture of hexoses (glucose, galactose and mannose) and of pentoses (xylose, arabinose and ribose). Xylose is the principal pentose present in the hemicelluloses, composing 17% to 31% of its dry weight. About 80% of the total xylose can be recovered as fermentable sugar in the hemicellulosic hydrolysates. The use of lignocellulosic materials for a cost-effective production of ethanol by Saccharomyces requires the total fermentation of xylose. This yeast, however, does not present a natural ability to convert xylose into ethanol. There are other yeasts capable of fermenting xylose, but the hemicellulosic hydrolysates contain several compounds such as organic acids, furans and phenols inhibiting the fermentation process. Therefore S. cerevisiae is the only known microorganism capable of fermenting effectively in this stressful environment (Olsson and Hahn-Hägerdal, “Fermentation of lignocellulosic hydrolysates for ethanol production”, Enzyme Microbial Technol. 18: 312-331, 1996).
[0006] Recombinant strains of S. cerevisiae have been produced in which two genes for xylose catabolism were inserted: xylose reductase (XR), which reduces xylose to xylitol, and xylitol dehydrogenase (XDH), oxidizing xylitol to xylulose. This compound is already naturally metabolized by S. cerevisiae following the pentose phosphate pathway and the glycolytic pathway for ethanol production. The genes for the XR and XDH enzymes were obtained from the yeast Pichis stipitis , which naturally ferments xylose. With these genes, S. cerevisiae metabolizes xylose, but does not produce ethanol in significant concentrations. In this yeast, xylulose is phosphorylated to xylulose-5-phosphate by means of a xylulose kinase (XK). The XK native gene was over-expressed in S. cerevisiae strains containing heterologous XR and XDH. The novel gene combination was object of chromosomal integration for producing strains with a stable phenotype and amenable to cultivation in industrial substrates (W09742307A1). The resulting strains produce significant ethanol concentrations, but with low productivity values.
[0007] Several strategies have been followed for improving the productivity in ethanol production from xylose by recombinant S. cerevisiae strains. Three of these strategies succeeded. One consisted in subjecting the S. cerevisiae recombinants to random mutagenesis, using EMS (ethyl methane sulphonate) as mutagenic agent, and selecting the obtained mutants for a more effective fermentation (US 2003/0157675 A1). Another approach subjected the recombinant strains to a strong selective stress, using continuous culture on chemostat and anaerobiosis, for selection of the most suitable ones for fermenting xylose (W003078643). The third strategy used the xylose catabolic pathway occurring usually in bacteria. In this group of microorganisms, the xylose is transformed directly into xylulose by means of a xylose isomerase (XI). The successive attempts to express XI of bacterial origin in S. cerevisiae had failed. Recently, a XI of fungal origin was isolated and expressed in S. cerevisiae (W003062430).
[0008] This document describes host cells transformed with a nucleic acid sequence encoding a xylose isomerase obtained from a filamentous fungus. This sequence confers to the host cell the ability to improve xylose metabolism. This improvement can also possibly be achieved by the expression of a heterologous pentose transporter. In fact, this document only discloses the isolation and cloning of a gene encoding a xylose isomerase and only considers the improvement in host cells of xylose metabolism by the hypothetical expression of a heterologous pentose transporter.
[0009] However, the productivities obtained in the production of ethanol from xylose, using the best strains available, is still inferior when compared to the ones obtained when the yeast ferments glucose. One possible obstacle for obtaining higher values is found when xylose enters the cell (Hahn-Hägerdal et al, “Metabolic engineering of Saccharomyces cerevisiae for xylose utilization”, Adv Biochem. Eng/Biotechnol. 73: 53-84, 2001; Jeffries and Jin, “Metabolic engineering for improved fermentation of pentose by yeasts”, Appl. Microbiol. Biotechnol. 63: 495-509, 2004).
[0010] Xylose is a weak substrate of the transporters mediating the fast entrance of glucose and other hexoses in S. cerevisiae. HXT transporters present an affinity towards xylose one or two times lower than towards glucose. Consequently, in the presence of glucose, xylose is not assimilated. In the absence of glucose, xylose assimilation and, consequently, the fermentative ability are also reduced. It is conceivable that the expression of transporters with higher affinity towards xylose, namely the ones transporting xylose through active transport mechanisms of the proton symport type, enable a more efficient production of ethanol. The energy consumption for transporting xylose into the cell may be translated, in strains with a xylose/proton symport, into a lower biomass yield, increasing concomitantly the specific productivity for ethanol production.
[0011] Among the yeasts capable of growing naturally in xylose, Candida intermedia PYCC 4715 stands out due to its high specific growth rate. It has been shown that this yeast produces two transport systems for xylose, one of the facilitated diffusion type and the other of the xylose/proton symport type, presenting the latter a higher affinity for xylose and being only produced when the xylose concentration was relatively low (Gárdony et al, “High capacity xylose transport in Candida intermedia PYCC 4715”, FEMS Yeast Res. 3: 45-52, 2003).
[0012] This yeast was considered adequate for isolating the gene of an active xylose transporter (GXS 1) to be expressed in S. cerevisiae . However, it is also mentioned that the three genes responsible for xylose uptake found and isolated so far from natural xylose-utilizing yeasts showed low affinity for xylose. In fact, all the results presented in this document refer not to genes or the corresponding enzymatic activities but to the ability to use xylose and to kinetic characteristics of xylose transport in whole yeast cells.
[0013] Despite the progress, the recombinant yeasts developed until now do not show enough efficiency in ethanol production from xylose. There is a need to improve the state of art for fermenting lignocellulosic materials and to produce bioethanol at the industrial level.
[0014] Document “Leandro, Maria et al.—Molecular characterisation of xylose transport in Candida intermedia . Yeast, vol. 20, n° Suppl. 1 (2003-07), pp. S246” discloses molecular approaches to the characterization of xylose transport in C. intermedia . In this document it is possible to read an explicit expression stating that “so far, no gene encoding such type of (active) transporter has been isolated from fungi”. In fact, this document describes an unsuccessful attempt to isolate the xylose symporter gene.
[0015] Document “Gardony, Mark et al.—Control of xylose consumption by xylose transport in recombinant Saccharomyces cerevisiae . Biotechnology and Bioengineering, vol. 82, n° 7 (2003-06), pp. 818-824″ describes the control exercised by the step of xylose transport over the xylose consumption rate by transformed S. cerevisiae strains expressing heterologous xylose reductase (XR) and xylitol dehydrogenase (XDH), and overexpressing the native xylulokinase (XK) gene. The main result was that the control was higher at low xylose concentrations, which is not in anyway related to isolation and cloning of genes encoding an active xylose/glucose transporter.
[0016] Since the 80's it has been known that yeasts produce active xylose transporters, the respective activities/capacities being regulated by the substrate concentration in the surrounding medium. However, the approaches followed by several groups worldwide to isolate and clone the corresponding gene were unsuccessful, mainly due to the routine experimental protocols followed in similar cases.
[0017] The present invention solves this problem developing a method for isolating this gene (responsible for the expression of an active xylose/glucose transporter) and further to clone it into a host cell thereby demonstrating xylose/glucose-H + symport activity. The step(s) that allowed the invention to achieve this outcome resulted from a combination of skills is yeast physiology, biochemistry and molecular biology, which is uncommon among those skilled in the art of gene cloning and isolation. In general, the higher activity of the symport at low xylose concentrations, described in document “Gárdony et al, “High capacity xylose transport in Candida intermedia PYCC 4715”, FEMS Yeast Res. 3: 45-52, 2003”, leads researchers to isolate the cDNA based on the increase in the respective mRNA and using RT (Reverse Transcriptase)-PCR and degenerate primers. This standard approach proved to be unsuccessful. However, in the present invention this problem is circumvented by comparing plasma membrane proteins obtained in inducing and repressing growth conditions. This innovative step allowed the isolation of the gene and transformation of the host cell. Demonstration of the presence of the xylose/glucose symporter in the transformed host cells required another innovative step, the co-transformation of both the xylose/glucose facilitator and the active transporter, to put in evidence biphasic kinetics of labelled glucose uptake by cells growing in relatively low glucose medium. This could not be achieved using a host cell transformed solely with the active xylose/glucose transporter due to its very low capacity.
SUMMARY OF THE INVENTION
[0018] Therefore, the problem the present invention aims to solve corresponds to offering a process for a more efficient and cost-effective bioethanol production from lignocellulosic materials.
[0019] The solution of this problem is based on the fact that the present inventors were able to identify and isolate a gene encoding an active transporter for xylose/glucose from C. intermedia with a surprisingly high affinity towards xylose in comparison to the transporters that occur naturally in fermentative yeasts. When inserted in a host cell, this gene turns it potentially more effective in consuming and fermenting the xylose present in the mixture of hexoses and pentoses resulting from raw materials of industrial interest for bioethanol production.
[0020] Thus, a first aspect of the invention refers to an isolated DNA fragment encoding an active transporter for xylose/glucose, characterized for comprising:
[0000] a nucleotide sequence SEQ ID No: 1; or
nucleotide sequence with a homology of at least 80% with the fragment from +1138 to +1315 of the SEQ ID No:1,
or its complementary sequences.
[0021] In a second aspect, the invention refers to a cDNA molecule, characterized for comprising:
[0000] a nucleotide sequence SEQ ID No: 1; or
a nucleotide sequence with a homology of at least 80% with the fragment from +1138 to +1315 of the SEQ ID No:1.,
or its complementary sequences.
[0022] In a third aspect, the invention refers to a plasmid, characterized for comprising a DNA fragment according to claim 1 .
[0023] In a fourth aspect, the invention refers to a host cell characterized for being transformed with the plasmid according to claim 3 , in order to allow the host cell to express the mentioned xylose/glucose active transporter.
[0024] In a last aspect, the invention refers to the use of a host cell transformed for ethanol production by means of xylose fermentation from a medium comprising a xylose source.
BRIEF DESCRIPTION OF THE FIGURES
[0025] FIG. 1 : Denaturing polyacrylamide gel electrophoresis (10% T) of 20 μg total proteins of plasma and mitochondrial membranes isolated from C. intermedia cells cultivated in 0.5% xylose (X), 2% glucose (G) and 4% xylose (4×). The gel was stained with Coomassie Blue. M—Sigma Marker (Wide Range), p—plasma membranes; n—mitochondrial membranes.
[0026] FIG. 2 : Amino acid sequence from the N-terminal region of the Gxs1p protein and degenerated primers designed from this region.
[0027] FIG. 3 : Northern Blot analysis of the GXS1 gene expression. Total RNA was isolated from C. intermedia PYCC 4715 cultures in Verduyn medium containing 0.5% xylose (X), 2% glucose (G) or 4% xylose (4×) as single carbon and energy source. Each sample contains 10 μg of total RNA, separated in a denaturating 1.2% agarose gel and subsequently transferred to a nylon membrane (Hybond-N). A 300 bp fragment, amplified by means of CiGXSL1 and CiGXSR3 primers, was used as specific probe for the GXS1 gene. A 172 bp fragment from the actin gene was amplified using the ActCiL1 (5′-AACAGAGAGAAGATGACCCAGA; SEQ ID NO:2) primer and the ActCiR1 (5′-GCAAAGAGAAACCAGCGTAAA; SEQ ID NO:3) primer and genomic DNA from C. intermedia PYCC 4715 as template. The probes were labelled with [α- 32 P]-ATP (Amersham Bioscience) using Prime-a-Gene Labelling System (Promega). Hybridizations and washings were performed as described by Griffioen et al (1996).
[0028] FIG. 4 : Nucleotide sequence of the GXS1 gene (SEQ ID No. 1), from the first (ATG) to the last (TAA) codon. The sequence +1138 until +1315 is shadowed.
[0029] FIG. 5 : Extracellular alkalinisation elicited by the addition of xylose (X) or glucose (G) to an aqueous suspension of cells of the MJY2 strain cultivated in mineral medium with 2% (w/v) of glucose.
[0030] FIG. 6 : Eadie-Hofstee representation of the initial transporter velocities of D-[ 14 C] xylose (♦) in cells of the MJY2 strain, obtained from a culture in mineral medium with 2% (w/v) of glucose, and of D-[ 14 C] glucose (□) in cells of the MJY5 strain, cultivated in mineral medium with 2% (w/v) of glucose and 0.05% of maltose.
DETAILED DESCRIPTION OF THE INVENTION
[0031] According to a preferred embodiment of the present invention, a process to express in S. cerevisiae a xylose active transporter was developed. This process comprises the insertion of heterologous DNA in yeasts, integrating from that point on a gene for a novel xylose transport system of the xylose/glucose-proton symport type.
[0032] Referring to this invention, a process for isolating, cloning and expressing the gene was followed. However, alternative processes may be used by those skilled in the art.
Identification of the Xylose/Glucose-H+ Active Transporter by SDS-PAGE
[0033] The xylose/glucose active transporter from C. intermedia was identified by comparison of the relative abundance of the proteins present in plasma membranes isolated from C. intermedia cells cultivated under inducing and repressing conditions. With this objective, plasma membranes and mitochondrial membranes were isolated from cells cultivated in Verduyn medium (Verduyn et al, 1992) containing, alternatively, 0.5% of xylose, 2% of glucose or 4% of xylose as single carbon and energy source. The cells were collected in the exponential phase of growth (DO 640 =0.8−2.0) and washed twice with ice-cold distilled water and once with buffer A (0.1 M of glycine, 0.3 M of KCI, pH 7.0). Ten to fifteen grams of cells were then resuspended in 15 ml of buffer A containing 0.1 mM PMSF. The isolation of the membranes was performed from this point on as described by Van Leeuwen et al (1991). With aliquots (20 μg) of the obtained samples, a denaturing polyacrylamide gel electrophoresis in the presence of tricine (Tricine SDS-PAGE; Schlaigger, 1994) was performed. The concentrations of acrylamide and bisacrylamide used in the gel were 10%T and 3%C (% T=total concentration of acrylamide+bisacrylamide and % C=percentage of bisacrylamide relatively to the total). The plasma membrane samples presented a band pattern obviously different from the one presented by the corresponding samples of mitochondrial membranes ( FIG. 1 ) indicating that an efficient separation of the two membrane types occurred. Consequently, it has been found that the observed differences between the band patterns from the plasma membrane samples, corresponding to the different carbon sources, are not a consequence of a contamination by mitochondrial proteins.
[0034] The most notable difference between the three plasma membrane samples is indicated by an arrow in FIG. 1 . It corresponds to a protein of about 40 kDa molecular weight that seems to be present only in plasma membranes of cells cultivated in 0.5% of xylose. As the molecular weight of this protein is in the expected range for a sugar transporter, it was considered that the band would probably correspond to the xylose/glucose active transporter, kinetically characterized in C. intermedia.
[0000] Cloning of the cDNA Encoding the Xylose/Glucose Active Transporter
[0035] The membrane protein, identified as described, was isolated from a preparative gel loaded with 250 μg of total membrane protein from C. intermedia cells cultivated in 0.5% of xylose. After electrophoresis, the proteins were transferred to a PVDF membrane (Sequi-blot from BIO-RAD). The electrophoresis and the transference were realized according to instructions provided by the manufacturer. The fraction of the membrane containing the protein of interest was cut-off and used for sequencing of the N-terminal end of the protein (Protein Core Facility, Columbia University, USA). The obtained sequence of 15 amino acids is indicated in FIG. 2 . From this sequence, degenerated primers were designed ( FIG. 2 ). These primers were used to amplify the cDNA through RACE (Rapid Amplification of cDNA Ends) technique, from total RNA of cells cultivated in 0.5% of xylose. For this purpose, a First Choice RLM-RACE kit (Ambion) was used, according to instructions provided by the manufacturer. The RNA was extracted as described by Griffioen et al (1996) and subsequently purified using RNA cleanup protocol (RNeasy kit, Quiagen). This RNA sample was used as template for the 3′ RACE protocol, in combination with the CiGXSL1 (5′-GARGAYAAYMGIATGGTIAARMG-3′; SEQ ID NO:4) and the CiGXSL2 (5′-AARMGITTYGTIAAYGTNGG-3′; SEQ ID NO:5) primers; I=inosine, Y=C/T, R=A/G, M=A/C and N=A/ T/ or C. Since the design of the primers was based on the sequence of the first amino acids of the protein, it was expected that the 3′ RACE reaction would produce the cDNA almost entirely. In fact, with this reaction a product of about 1.7 kb was obtained, which was cloned in the pMOSBlue vector (Amersham Biosciences) and partially sequenced, using an automatic sequencer ALF Express (Amersham Pharmacia Biotech) and Cy5-labelled primers specific for the vector sequences. The protein encoded by this molecule presented the characteristic properties of a sugar transporter. Next, a Northern blot analysis was performed, which showed that the respective mRNA was abundant in cells cultivated in 0.5% of xylose but was not detectable in cells cultivated in 2% of glucose ( FIG. 3 ).
[0036] The 5′ end from the cDNA was obtained through the 5′ RACE technique, using the CiGXSR3 (5′-CGTTAAGGAATGGAGCACAAAG-3′; SEQ ID NO:6) primer. The fragments obtained were cloned and sequenced as described in the prior paragraph, showing that an additional amino acid (initializing methionine) and a leader sequence of 28 or 31 amino acids are encoded, indicating the existence of two active sites of transcription initiation. The novel gene was designated GXS1 (Glucose Xylose Symport 1). The correspondent nucleotide sequence (SEQ ID No. 1) is presented in FIG. 4 .
[0000] Functional Expression in S. cerevisiae
[0037] To confirm that the novel transporter encoded by the GXS1 gene was a transporter for glucose and xylose, several plasmids were engineered allowing the expression of the cDNA in S. cerevisiae . A high copy number vector (pMA91; Kingsman et al, 1990), containing the promoter and terminator regions of the PGK1 gene, was used to clone the cDNA from GXS1 in the following way: the total encoding region of the GXS1 gene was amplified by PCR using the GXS1P1 (5′-ATAGCAGATCTCATATGGGTTTGGAGGACAATAGAATG-3′; SEQ ID NO:7) primer and the GXS1P2 (5′-ATAGCAGATCTTCTAGATTAAACAGAAGCRRCTTCAGAC-3′; SEQ ID NO:8) primer. Both primers have a recognition sequence for BglII at the 5′ end and, additionally, they also have recognition sequences for NdeI and XbaI. The pMA91 plasmid was then digested with BglII and ligated with the fragment containing the encoding region from GXS 1, digested with the same enzyme, originating the pPGK-GXS1 plasmid.
[0038] A different chimeric gene was engineered using the truncated promoter of the HXT7 gene and was cloned in the YEpLac 195 (multi-copy) and YCpLac 111 (single-copy) vectors (Gietz et al, 1988). A DNA fragment comprising the nucleotides −392 to −1 from the HXT7 promoter was amplified by PCR using the HXT7prom1 (5′-AACCTGCAGCTCGTAGGAACAATTTCGG-3′; SEQ ID NO:9) primer and the HXT7prom2 (5′-GGACGGGACATATGCTGATTAAAATTAAAAAAACTT-3′; SEQ ID NO: 10) primer and the YEpkHXT7 plasmid (Krampe et al, 1998) as template. The fragment was subsequently digested with PstI and NdeI, since the primers contain recognition sites for these enzymes, being afterwards ligated to the YEpLac 195 plasmid, digested with PstI and XbaI, originating the pHGXS1 plasmid. Subsequently, a 0.3 kb fragment containing the terminator region of the PGK gene was amplified using the PGK1 term 1 (5′ -ACCGTGTCTAGATAAATTGAATTGAATTGAATCGATAG-3′; SEQ ID NO:11) primer and the PGK1term2 (5′-TAATTAGAGCTCTCGAAAGCTTTAACGAACGCAGAA-3′; SEQ ID NO:12) primer and the pMA91 plasmid as a template. The primers have at its 5′ ends recognition sites for the XbaI and SacI enzymes, respectively. The fragment containing the terminator region of the PGK gene was subsequently digested with these enzymes and ligated between the XbaI and SacI sites of the pHGXS1 plasmid, originating the pHXT7-GXS1 plasmid.
[0039] Finally, the pHXT7-GXS1 plasmid was digested with PstI and SacI generating a fragment containing the total chimeric gene, which was subsequently inserted in the YCplac 111 vector (Gietz et al, 1988), digested with the same enzymes, originating the pHXT7-GXS1 plasmid.
[0040] The three plasmids were then used to transform S. cerevisiae TMB 3201 (MATa Δhxt1-17 Δgal2 Δstl1 Δagt1 Δmph2 Δmph3 leu2-3,112 ura3-52 trp1-289 his3-Δ1 ::YIpXR/XDH/XK MAL2-8 c SUC2; Hamacher et al, 2002). This strain is not capable of using glucose or xylose as carbon and energy source because it does not express any transport system for these sugars. The transformations originated the MJY2-4 strains: MJY2 (TMB 3201+pHXT7-GXS1), MJY3 (TMB 3201+pPGK-GXS1) and MJY4 (TMB 3201+pHXT7-GXS1-s).
[0041] The incapacity of growing in glucose or xylose was overcomed by complementation in both strains containing plasmids with high copy number (MJY2 and MJY3), but the growth in xylose, as single carbon and energy source, was very weak and only in a solid medium culture. The MJY4 strain, containing a plasmid of low copy number, presents a very weak growth in glucose and absence of growth in xylose, suggesting that the occurrence of complementation is dependent on a stronger expression of the gene than the one possible to obtain with this plasmid.
[0042] The MJY2 strain was used for investigating the presence of xylose and glucose active transporter. The addition of D-glucose or D-xylose (final concentration of 6.7 mM) to an aqueous suspension of cells (about 30 mg dry weight/ml) of the MJY2 strain, cultivated in YNB medium (Yeast Nitrogen Base) supplemented with 2% (w/v) of glucose, leucine and tryptophan, triggers an increase of the extracellular pH in both cases, indicating the existence of an influx of protons associated to the transport and, therefore, an active transport system co-transporting sugar and H + occurs ( FIG. 4 ). This assay shows that the GXS1 gene encodes a transporter with an active transport mechanism, which accepts as substrate both glucose and xylose.
[0000] Kinetics of sugar transport by Gxs1p
[0043] The kinetic constants from transport mediated by Gxs1p were determined in the MJY2 strain, expressing only the active transport system. However, despite its high affinity, the capacity of this transporter does not allow high transport velocities comparable to the facilitated diffusion system. Therefore, in order to give a better sense of the values to be obtained in the kinetic assays with 14 C-D-glucose (Spencer-Martins et al, 1985), substrate for which the affinities of the two transport types differ just in one order of magnitude (facilitated diffusion: K m =2-4 mM; symport: K m =0.2 mM; 25° C., pH 5) instead of two as with xylose (facilitated diffusion: K m =49 mM; symport: K m =0.4 mM; 25° C., pH 5), the MJY5 strain expressing the two transport types present in C. intermedia was used for this purpose. In FIG. 5 , an obvious two-phase kinetics for glucose may be observed, indicative for the simultaneous presence of a transport system of the facilitated diffusion type and of the now identified and cloned active transporter of the xylose/glucose-H + symport type, with high relative affinity. The kinetic parameters determined in these conditions in S. cerevisiae were similar to the ones obtained in C. intermedia , origin of the GXS1 gene.
[0000] Homology with Other Transporters
[0044] The characterization of GXS1 allowed discovering a protein family with some homology towards Gxs1p and which are present in other yeasts ( Debaryomyces hansenii, Yarrowia lipolytica and Candida albicans , GenBank accession numbers: CAG86664, EAL01541 and CAG81819, respectively). For none of these proteins is the function known (they are registered in the databases as putative sugar transporters). | The present invention confers to the ferementative yeast Saccharomyces cerevisiae , genetically modified by insertion of a nucleic acid sequence encoding a xylose and a glucose active transporter, the ability to assimilate xylose using a system of co-transport with protons exhibiting a high affinity for xylose. The invention is useful for the production of bioethanol from plant biomass and other lignocellulosic materials, using genetically modified microorganisms for assimilating and fermenting xylose in mixtures of hexoses and pentoses resulting from raw material of industrial interest. | 2 |
FIELD OF INVENTION
This invention relates to a method for playing a casino game as a computer video game, and more particularly to a modified video poker game.
PRIOR ART
The basic game of video poker has been in casinos for approximately ten years and several variations of this very popular game have appeared. In the basic game, the player is allowed to inspect five cards randomly chosen by the computer. These cards are displayed on the video screen and the player chooses which cards, if any, that he or she wishes to hold. If the player wishes to hold all of the cards, i.e. stand, he or she presses a STAND button. If the player wishes to hold only some of the cards, he or she chooses the cards to be held by pressing HOLD keys located directly under each card displayed on the video screen. Pushing a DEAL button after choosing the HOLD cards automatically and simultaneously replaces the unchosen cards with additional cards which are randomly selected from the remainder of the deck. After the STAND button is pushed, or the cards are replaced, the final holding is evaluated by the game machine's computer and the player is awarded either play credits or a coin payout as determined from a payoff table. This payoff table is stored in the machine's computer memory and is also displayed on the machine's screen. Hands with higher poker values are awarded more credits or coins. Very rare poker hands are awarded payoffs of 800-to-1 or higher.
Video poker games have become immensely popular because they combine the card strategy of games like blackjack with potentially large jackpot payoffs typical of reel-type slot machines.
In addition to the basic video poker game described above, several other variations of video poker exist. Currently, the most popular variations include wild cards, which provide an extra degree of volatility to the basic game and consequently appeal to a specific group of video poker enthusiasts. The wild cards are typically deuces, a joker or a combination thereof.
Another variation pays the player for either high- or low-valued poker hands. Upon inspecting the original five cards, the player must choose whether to try for a high-valued hand or a low-valued hand when drawing additional cards. This variation is not as popular as the wild card variation and has never met with much commercial success.
Another variation known as 2nd Chance Poker is disclosed in U.S. Pat. No. 4,743,022. This game is played in the same manner as the basic video poker game except that, with an additional bet, a sixth card may be drawn to improve the hand. The payoff table is changed in the computer when the sixth card is drawn to reflect the changed odds.
Another prior art game is disclosed in U.S. Pat. No. 5,033,744 to Bridgeman, et al. This reference describes a variation of video poker in which cards not designated as HOLD cards are replaced one card at a time. This variation enables the player to inspect the five card holding after each card is replaced individually rather than after all of the cards have been replaced. Additionally, a constant payoff table is provided. This means that a winning hand is awarded the same payoff regardless of the number of cards drawn to achieve it. The '744 reference describes the use of guiding symbols to advise the player as to which cards to replace to improve the value of the poker hand. This variation also contains a provision for an instant game ending for winning hands which are at or exceed a predetermined winning hand level designed into the machine. When such a hand is recognized by the machine's computer, the game immediately ends independent of any action by the player.
All of the characteristics which are described in the '744 reference produce a game which is extremely advantageous for the player. Consequently, the game's profitability would be unacceptably low for casino owners unless the constant payoff table was reduced to offset this problem. Reducing payoffs, however, would make the '744 video poker game unacceptable to players because of its inability to match payoffs for similar winning hands achieved on the basic game.
Present variations of video poker do not provide the player with an initial player commitment to the number of draw cards, nor do they provide payoff tables which vary depending on the number of draw cards selected. Additionally, there are no provisions for an early END-GAME-with-reduced-payoffs feature. Also, a game with these features should embody the same degree of profitability to casino owners, or "expected player return" to players, as the current basic game. A video poker game with these features would not only appeal to players who seek an additional degree of card strategy and player involvement, but would also appeal to casino owners.
SUMMARY OF INVENTION
Therefore, it is an object of this invention to provide a unique variation of video poker which is offers a high level of player involvement and is easy to learn.
Another object of this invention is to provide a video poker variation which provides winning hand payoffs similar to the basic video poker game.
Yet another object of this invention is to provide a video poker game variation which assures a level of profitability for casinos which is equivalent to the currently produced basic video poker game.
These and other objects and advantages of this invention shall become apparent from the following descriptions of the invention.
Accordingly, a casino type video poker game is described wherein a player places his or her bet inro the machine and pushes a button labelled DEAL. The first five cards are displayed on the video screen and the player is allowed to inspect these cards and designate the number of cards he or she wishes to draw. At this point, the player only commits to the number of draw cards and not the actual cards to be replaced. The player then designates the number of cards by entering a draw value into the machine. The player accomplished this by pressing the button on the console which corresponds with the number of cards he or she wishes to draw. Before proceeding further, the player can change his or her mind and select a different number of draw cards by pushing another button on the console labelled "CANCEL". If the player does not wish to draw any cards, a button labelled "STAND" is pressed. The player then proceeds to replace the designated number of draw cards one card at a time. Replacement of a draw card is accomplished by pressing a button labelled "DRAW". One DRAW button is positioned under each card under the video screen. The computer then replaces the selected draw card with a card randomly chosen from the remaining cards in the deck and prints a "DRAWN" message on the screen under the new card. Once a card has been replaced with a new card, the new card in that position on the video screen cannot be replaced again and the "DRAWN" message under the card is an indication to the player of this limitation. A draw counter which is displayed on the video screen shows the remaining number of draw cards available to the player and is decremented each time a new card is drawn.
If the player receives a winning hand by drawing fewer cards than he or she originally anticipated, he or she can end the game by pressing a button labelled "END GAME". Otherwise, the player can replace all of the committed number of draw cards. When all of the draw cards are used, the game is over. It this point, the machine's computer evaluates the final hand displayed and pays off accordingly. The payoff for winning hands either in play credits or coins, is based on a payoff table which is stored in the computer's emory and also displayed to the player during play.
Variable payoff tables are used to determine the payoff per unit bet. The more cards that are drawn to achieve a winning hand, the lower the long-term, overall payoff. If the END GAME feature is used, the player is paid at a rate equal to one-half of the rate for a winning hand if all of the committed cards had been drawn.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram illustrating the game's initial steps at the beginning of play;
FIG. 2 is a block diagram illustrating the play sequence when the player chooses to draw five cards;
FIG. 3 is a block diagram illustrating the play sequence when the player decides to STAND (i.e. draw zero cards);
FIG. 4 is a block diagram illustrating the play sequence when the player decides to draw one card;
FIG. 5 and FIG. 6 are block diagrams illustrating the play sequence when the player decides to draw two cards;
FIGS. 7 and 8 are block diagrams illustrating the play sequence when the player decides to draw three cards;
FIGS. 9 and 10 are block diagrams illustrating the play sequence when the player decides to draw four cards;
FIGS. 11 and 12 are block diagrams illustrating the sequence at the final stages of any hand, including evaluation of the final five card holding and determination of the appropriate payoff;
FIG. 13 illustrates a console and display of a video poker game machine according to the present invention after receiving a bet from a player;
FIG. 14 illustrates the console and display of the present invention after the player has committed to a particular number of draw cards;
FIG. 15 illustrates the console and display of the present invention after the player has drawn one card.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1, a player begins the game by placing a bet 20. This is accomplished by inserting coins or bet credits into the video poker machine. The computer then records the bet size 22 in its memory, displays the bet size on the screen 24 and displays one of the following composite payoff tables 26, depending on the bet size:
__________________________________________________________________________COMPOSITE PAYOFF TABLE DRAW ANY ONE, TWO DRAW ANY DRAW ANY FIVE CARDS OR "STAND" THREE CARDS FOUR CARDS__________________________________________________________________________Payoffs For 5 Coins BetROYAL FLUSH 4000 4000 4000STRAIGHT FLUSH 250 250 250FOUR OF A KIND 125 100 100FULL HOUSE 40 30 30FLUSH 30 20 20STRAIGHT 20 20 20THREE OF A KIND 15 10 10TWO PAIR 10 10 5HIGH PAIR (JACKS OR BETTER) 5 5 5Payoffs For 4 Coins BetROYAL FLUSH 1000 1000 1000STRAIGHT FLUSH 200 200 200FOUR OF A KIND 100 80 80FULL HOUSE 32 24 24FLUSH 24 16 16STRAIGHT 16 16 16THREE OF A KIND 12 8 8TWO PAIR 8 8 4HIGH PAIR (JACKS OR BETTER) 4 4 4Payoffs For 3 Coins BetROYAL FLUSH 750 750 750STRAIGHT FLUSH 150 150 150FOUR OF A KIND 75 60 60FULL HOUSE 24 18 18FLUSH 18 12 12STRAIGHT 12 12 12THREE OF A KIND 9 6 6TWO PAIR 6 6 3HIGH PAIR (JACKS OR BETTER) 3 3 3Payoffs For 2 Coins BetROYAL FLUSH 500 500 500STRAIGHT FLUSH 100 100 100FOUR OF A KIND 50 40 40FULL HOUSE 16 12 12FLUSH 12 12 12STRAIGHT 8 8 8THREE OF A KIND 6 6 6TWO PAIR 4 4 2HIGH PAIR (JACKS OR BETTER) 2 2 2Payoffs For 1 Coin BetROYAL FLUSH 250 250 250STRAIGHT FLUSH 50 50 50FOUR OF A KIND 25 20 20FULL HOUSE 8 6 6FLUSH 6 4 4STRAIGHT 4 4 4THREE OF A KIND 3 2 2TWO PAIR 2 2 1HIGH PAIR (JACKS OR BETTER) 1 1 1__________________________________________________________________________
As shown on the tables, the payoff increases as more coins or credits are bet by the player. A message indicating that payoffs are reduced by half if the game is ended early may also be displayed on the screen.
After the computer records the bet size 22, the player presses a "DEAL" button 28. The computer then randomizes the card deck 30 and selects five cards from the "shuffled" deck 32. The five cards chosen by the computer 32 are then displayed on the screen 34 along with a message instructing the player to either select a number of draw cards or STAND 36. At this point, the player decides the number of cards he or she wishes to draw 38. This initial decision commits the player to a specific number of draw cards, and also enables the computer to choose an appropriate payoff table and display it on the screen. The computer displays one of the following tables throughout game play:
PAYOFF TABLE 1______________________________________For Selections of ONE, TWO or FIVE DRAW CARDS,or "STAND" Number of Coins Bet 1 2 3 4 5______________________________________ROYAL FLUSH 250 500 750 1000 4000STRAIGHT FLUSH 50 100 150 200 250FOUR OF A KIND 25 50 75 100 125FULL HOUSE 8 16 24 32 40FLUSH 6 12 18 24 30STRAIGHT 4 8 12 16 20THREE OF A KIND 3 6 9 12 15TWO PAIR 2 4 6 8 10HIGH PAIR (JACKS 1 2 3 4 5OR BETTER)______________________________________
PAYOFF TABLE 2______________________________________For Selection of THREE DRAW CARDS Number of Coins Bet 1 2 3 4 5______________________________________ROYAL FLUSH 250 500 750 1000 4000STRAIGHT FLUSH 50 100 150 200 250FOUR OF A KIND 20 40 60 80 100FULL HOUSE 6 12 18 24 30FLUSH 4 8 12 16 20STRAIGHT 4 8 12 16 20THREE OF A KIND 2 4 6 8 10TWO PAIR 2 4 6 8 10HIGH PAIR (JACKS 1 2 3 4 5OR BETTER)______________________________________
PAYOFF TABLE 3______________________________________For Selections of FOUR DRAW CARDS Number of Coins Bet 1 2 3 4 5______________________________________ROYAL FLUSH 250 500 750 1000 4000STRAIGHT FLUSH 50 100 150 200 250FOUR OF A KIND 20 40 60 80 100FULL HOUSE 6 12 18 24 30FLUSH 4 8 12 16 20STRAIGHT 4 8 12 16 20THREE OF A KIND 2 4 6 8 10TWO PAIR 1 2 3 4 5HIGH PAIR (JACKS 1 2 3 4 5OR BETTER)______________________________________
If the player chooses to draw five cards 40, the play sequence takes place according to FIG. 2. The player indicates this choice by pressing the "5" button 42 on the console. The computer then displays payoff Table 1 44 and randomly chooses five new cards 46. The old cards are automatically replaced sequentially by the computer. The computer first erases the originally drawn card 48, displays the new, randomly chosen card 50, and displays the word "DRAWN" under the new card 52. Subsequent cards are replaced in the same manner until the fifth new card is displayed 50 and the "DRAWN" message is displayed underneath it 52. At this point, "GAME OVER" is displayed 54 and the hand rank is determined 56. From this hand rank, the payoff can be calculated 58.
FIG. 3 illustrates the play sequence if the player decides not to replace any of the cards 60. When the "STAND" button is pressed 62, the computer automatically displays Payoff Table 1 44 and "GAME OVER" 54 and determines the hand rank from the unchanged original holding 56. From this rank, the payoff can be determined 58.
If the player decides to replace only one card 70 the game progresses according to FIG. 4. When the player presses the "1" button 72, the computer displays Payoff Table 1 44 along with a draw counter indicating that the player has one card to draw 74. The draw counter is decremented each time a new card is drawn.
At this point, the player has three options. If the player decides to change his or her mind about the number of cards to draw, he or she may press the "CANCEL" button to make a new decision 76. This action returns the player to 38.
If the player chooses to end the game at this point, he or she may press the "END GAME" button 78. The player may choose to end the name early because a winning hand may have been achieved by drawing fewer cards than he or she originally anticipated. When confronted with a winning hand that could be reduced in value by drawing additional cards, players can opt to take a reduced payoff rather than risk getting no payoff at all. This early "END GAME" feature with reduced payoffs is not only unique to this invention, but is also necessary for another reason; if payoffs were not reduced with the "END GAME" feature, players would simply elect to always draw the maximum number of cards and then press the "END GAME" button whenever any winning hand is achieved. This would not be profitable for the casino owner and therefore, in the preferred embodiment, the player is paid at a rate equal to one-half of the rate for a winning hand if all of the committed cards had been drawn. Payoff tables reflecting these reduced winnings are shown below:
PAYOFF TABLE 4______________________________________For Selections of ONE or TWO DRAW CARDS and also"END GAME" Feature Number of Coins Bet 1 2 3 4 5______________________________________ROYAL FLUSH 125 250 375 500 750STRAIGHT FLUSH 25 50 75 100 125FOUR OF A KIND 12 25 37 50 62FULL HOUSE 4 8 12 16 20FLUSH 3 6 9 12 15STRAIGHT 2 4 6 8 10THREE OF A KIND 1 3 4 6 7TWO PAIR 1 2 3 4 5HIGH PAIR (JACKS 0 1 1 2 2OR BETTER)______________________________________
PAYOFF TABLE 5______________________________________For Selection of THREE DRAW CARDS and also"END GAME" Feature Number of Coins Bet 1 2 3 4 5______________________________________ROYAL FLUSH 125 250 375 500 750STRAIGHT FLUSH 25 50 75 100 120FOUR OF A KIND 10 20 30 40 50FULL HOUSE 3 6 9 12 15FLUSH 2 4 6 8 10STRAIGHT 2 4 6 8 10THREE OF A KIND 1 2 3 4 5TWO PAIR 1 2 3 4 5HIGH PAIR (JACKS 0 1 1 2 2OR BETTER)______________________________________
PAYOFF TABLE 6______________________________________For Selection of FOUR DRAW CARDS and also"END GAME" Feature Number of Coins Bet 1 2 3 4 5______________________________________ROYAL FLUSH 125 250 375 500 750STRAIGHT FLUSH 25 50 75 100 125FOUR OF A KIND 10 20 30 40 50FULL HOUSE 3 6 9 12 15FLUSH 2 4 6 8 10STRAIGHT 2 4 6 8 10THREE OF A KIND 1 2 3 4 5TWO PAIR 1 1 1 2 2HIGH PAIR (JACKS 0 1 1 2 2OR BETTER)______________________________________
In this case, the computer displays Payoff Table 4 80 and a "GAME OVER" message 54 and goes directly to determining the hand rank 56 and calculating the appropriate payoff 58.
If the player decides to stay with his or her initial commitment to draw one card, he or she chooses the draw card to replace and presses the button corresponding to that card 82. The computer then randomly chooses a card 84, erases the card selected by the player 48 and displays the drawn card 50 and the "DRAWN" message underneath it 52 as well as the "GAME OVER" message 54. The hand rank is then determined 56 and an appropriate payoff is calculated 58.
Referring to FIG. 5 and FIG. 6, the player in this case decides to draw two cards 90 and indicates this choice by pressing the "2" button 92 which then prompts the computer to display Payoff Table 1 44 and the draw counter indicating the number of draw cards remaining 74. At this point, the player has three choices. The player may choose to cancel his or her initial choice as to the number of draw cards by pressing "CANCEL" 76, which takes the player back to 38. If the player chooses to press the "END GAME" button 78, Payoff Table 4 is displayed 80 along with the "GAME OVER" message 54, and the hand rank is automatically determined 56 along with the appropriate payoff 58.
If the player decides to replace a card, he or she presses the button which corresponds with the card to be replaced 82. The computer then randomly draws a new card 84 erases the card selected by the player 48 and displays the new card 50 along with a "DRAWN" message 52. The computer then decrements the draw counter and displays the number of draw cards remaining 94, in this case, one card.
The player may now choose to either end the game or to replace another card. In this particular case, if the "END GAME" button is pressed 78, Payoff Table 4 is displayed 80 with the "GAME OVER" message 54 and hand rank is determined 56 along with the appropriate payoff 58.
If the player chooses to replace the remaining card, he or she presses the button corresponding to the selected card 82, which then prompts the computer to draw another random card 84, erase the selected card 48, and display the newly drawn card 50 and a "DRAWN" message underneath it 52. At this point, the computer also displays the "GAME OVER" message 54 and determines the hand rank 56 and the corresponding payoff 58.
FIGS. 7 and 8 show the play sequence if the player decides to draw three cards 100. The progression of the game is quite similar to the sequence just described. The player indicates his or her choice by pressing the appropriate button 102, which in turn prompts the computer to display Payoff Table 2 104, and the draw counter indicating the number of cards the player has chosen to draw 74. As before, the player may press the "CANCEL" button to make a new decision on the number of cards to draw 76 and return game play to 38. As before, the player may also choose to press "END GAME" 78, which prompts the computer to display Payoff Table 5 106 and the "GAME OVER" message 78 as well as to determine hand rank 56 and the appropriate payoff 58.
If the player chooses to replace one or more cards, he or she can do this one card at a time and examine the hand after each individual card is drawn. As always, replacement is accomplished by pressing a DRAW button which is positioned under each card 82. The computer then randomly chooses a card 84 and erases the card selected by the player 48. The new card is then displayed 50 along with the "DRAWN" message 52. The computer then decrements the draw counter and displays the number in the counter as the number of cards left to draw 94. If, at this point, the player has a winning hand and does not wish to draw anymore cards, he or she may choose to press the "END GAME" button 78, which in turn causes the computer to display Payoff Table 5 106 and the "GAME OVER" message 54. Hand rank 56 and payoff 58 is determined at this point. If the player chooses to continue drawing and replacing cards, he or she may press a button corresponding to the next card to replace 82. Each time a card is selected by the player and replaced by the computer, the draw counter is decremented and the player has a choice to either end the game or replace another card until the number of committed cards is replaced and the draw counter thereby equals zero. As before, the "GAME OVER" message is displayed 54 and the hand rank is determined 56 when the draw counter reaches zero or the "END GAME" button is pressed 78.
FIGS. 9 and 10 show the play sequence when the player chooses to draw four cards 110. The player indicates his or her choice by pressing button "4" 112 which signals the computer to display Payoff Table 3 114 and the draw counter indicating the number of draw cards remaining 74. Like the previous play sequences, the player can either press "CANCEL" to choose a different number of cards to draw 76 and go back to 38, press "END GAME" to display Payoff Table 6 116 and the "GAME OVER" message 54 and to determine the hand rank 56 and corresponding payoff 58 or choose a card to replace 82. Replacing a card takes place in the usual manner. The player presses the button under the card he or she wishes to replace 82, letting the computer randomly choose a card 84, erase the card selected by the player 48, display the new card 50 and the "DRAWN" message 52 and decrement the draw counter 94. After replacing at least one card, the player can either choose to press the "END GAME" button 78, which signals the computer to display Payoff Table 6 116 and the "GAME OVER" message 54 and also to determine the hand rank 56 and the corresponding payoff 58. The player may also choose to replace another card 82, and therefore re-initiate the draw-erase-display-decrement cycle. After each draw card replacement cycle, the player can either choose to end the game or replace another card until the counter reaches zero.
Referring now to FIGS. 11 and 12, the computer evaluates hand rank 56 and corresponding payoff 58 after all of the committed cards have been replaced for the particular hand or the "END GAME" button is pushed. The computer first evaluates whether the final five card holding is a losing hand or a winning hand. If the final five card holding is a losing hand, the computer displays a consolation message 118 and returns 119 to take the next bet 20.
If the final holding is a winning hand, the computer then checks to see if the "END GAME" option had been selected 120. If the option had not been selected, then the payoff table is determined by the number of draw cards that the player had selected. If 0, 1, 2 or 5 cards had been selected, then Payoff Table 1 44 is used to determine the payoff per unit bet. Payoff Table 2 is used if three cards were selected 104, and Payoff Table 3 is used if four cards were selected 114. The computer also checks if five coins were bet 121 to determine whether certain bonus payoff rates should be awarded.
If the "END GAME" option was selected 78, then a different set of tables with reduced payoffs is used to determine the payoff per unit bet. Payoff Table 4 is used if one or two cards were selected 80, Payoff Table 5 is used if three cards were selected 106, and Payoff Table 6 is used if four cards were selected 116. Regardless of the table used to determine the payoff per unit bet, the computer assigns a rank value corresponding with the rank of the hand and multiplies this number by the bet size recorded 22 to determine the final payoff 122. This payoff is displayed on the screen 124 and disbursed to the player in the form of coins or play credits 126. The machine then resets itself 119 to return to 20 and take the next bet.
To further clarify the present invention, FIG. 13 shows a console and display of the video poker machine according to the present invention 130. The console itself has a screen 132 and an arrangement of buttons 134 that the player would use to play the game. Buttons 134 available for player use at a particular point in the game are shaded in the figures. In practice, it is customary to illuminate these buttons or even to have the illumination flashing. This particular figure shows the console after the player has made a 5 coin bet by inserting coins or using the BET CREDIT button 136. The DEAL button 138 has been pushed and the first five cards are now displayed for the player's inspection. At this point, the composite payoff table 140 is displayed on the screen. The player may now either select a number of draw cards or press the STAND button 142. A message 144 and arrows at the bottom of the video screen instruct the player to select a number of draw cards or press STAND. In the preferred embodiment, the STAND button 142 may be used as a dual function button to either allow the player to STAND or END GAME. Additionally, the DEAL button 138 can also be used as a CANCEL button. Since these functions will not be used at the same point in any game, the dual function is practical.
FIG. 14 shows the screen and console 130 after the player has decided to draw four cards. The payoff table 145 for four cards is now displayed on the screen 132. The player may now choose to draw cards, press the END GAME button 146 to end the game, or press the CANCEL button 148 to choose a different number of draw cards. Since the player has not yet actually replaced any cards, he or she can still CANCEL the decision to draw four cards. The screen 132 now shows the number of cards selected 150 and a draw counter 152.
FIG. 15 shows the screen and console 130 after the player has drawn the first card. The information in the draw counter 152 has been updated to let the player know that he or she now has three cards left to draw. The CANCEL feature 148 is no longer available since the card has already been drawn. Also a "DRAWN" message 154 under the new card and the absence of illumination from the button 134 under the drawn card indicates to the player that this card is not available to replace during subsequent selections. This procedure is repeated until no more cards are left to draw (i.e. the draw counter 152 equals zero), or the player pressed the END button 146. Either of these would end the game and result in an evaluation of the displayed five card holding with an appropriate payoff.
The following tables compare the "expected player return" between the basic game of video poker and the video poker game which is our preferred embodiment.
TABLE 18______________________________________EXPECTED PLAYER RETURN FOR "9-6"BASIC VIDEO POKER MACHINE Frequency of Occurrence Payoff Per Contribution ToHand (%) Unit Bet Expected Return______________________________________Royal Flush 0.00255 800(*) 2.040Straight Flush 0.01115 50 0.558Four Of A Kind 0.23582 25 5.896Full House 1.14860 9 10.337Flush 1.15174 6 6.910Straight 1.27175 4 5.087Three Of A Kind 7.41034 3 22.231Two Pair 12.84670 2 25.693High Pair 21.08390 1 21.084None Of Above 54.83205 0 0.000TOTALS 100.00000% 99.836%______________________________________ (*)Assumes Five Coins Are Bet
TABLE 19______________________________________EXPECTED PLAYER RETURN FOR VIDEO POKERWITH MULTIPLE PLAYER CHOICES Frequency of Effective Contribution Occurrence Payoff Per To ExpectedHand (%) Unit Bet Return______________________________________Royal Flush 0.00255(#) 800.00(*) 2.04%Straight Flush 0.01115(#) 50.00 0.56%Four Of A Kind 0.29 22.40 6.50%Full House 1.55 6.78 10.51%Flush 1.05 5.44 5.71%Straight 1.28 4.00 5.12%Three Of A Kind 8.09 2.20 17.80%Two Pair 15.08 1.77 26.69%High Pair 23.22 1.00 23.22%None Of Above 49.44 0.00 0.00%TOTALS 100.00% 98.15%______________________________________ (#)Same Percentages As Basic Video Poker (*)Assumes Five Coins Are Bet
The mathematical analysis for the basic video poker game in Table 18 was computed by the Seattle Gaming Institute and published in their book "A Guide To Video Poker" in 1982. The analysis for the present invention in Table 19 is based on the actual play of 10,000 hands of the new game using an optimized playing strategy developed by the developers. Since 10,000 hands did not yield a statistically significant number of royal flush and straight flush winning hands, these "frequency of occurrence" percentage values were copied from the values found for the basic video poker game. This was felt to be fairly accurate since these hands are very rare and their play is fairly standard.
Of particular interest in Tables 18 and 19 is that the expected player returns are virtually identical for both the basic video poker game and the present invention. This was achieved by tailoring the payoff tables of the invention as described herein. The equal expected player returns assures playing satisfaction for the player and profitability for the casino owner.
The invention has been described in conjunction with a specific embodiment; however, there are many alternatives, modifications and variations which will be apparent to those skilled in the art in light of the foregoing description. Accordingly, the invention is intended to embrace all such alternatives, modifications, and variations that fall within the scope of the following claims. | An improved video poker variation in which the player must make an initial commitment as to the number of draw cards. The player then uses draw cards to replace unwanted cards one at a time. Payoff tables are varied depending on the number of draw cards selected. The game also provides the player with an option to end the game prior to drawing the committee number of cards with a reduced final payoff. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a U.S. National Phase Application of International Application No. PCT/EP2011/052298 filed Feb. 16, 2011, which claims priority to European Patent Application No. 10153989.8 filed Feb. 18, 2010. The entire disclosure content of these applications are herewith incorporated by references into the present application.
FIELD OF INVENTION
The invention relates to a clutch mechanism for the transmission of rotary movement from a gear arrangement, in particular for use in an auto-injector for releasing a protective needle shroud at the end of an injection stroke.
BACKGROUND
Auto-injectors are devices which completely or partially replace activities involved in parenteral drug delivery from standard syringes. These activities may include removal of a protective syringe cap, insertion of a needle into a patient's skin, injection of the medicament, removal of the needle, shielding of the needle and preventing reuse of the device.
Administering an injection is a process which presents a number of both mental and physical risks and challenges. The use of an auto-injector can bring many benefits for the user and healthcare professional.
US 2002/0095120 A1 discloses an automatic injection device which automatically injects a pre-measured quantity of fluid medicine when a tension spring is released. The tension spring moves an ampoule and the injection needle from a storage position to a deployed position when it is released. The content of the ampoule is thereafter expelled by the tension spring forcing a piston forward inside the ampoule. After the fluid medicine has been injected, torsion stored in the tension spring is released and the injection needle is automatically retracted back to its original storage position.
SUMMARY
It is an object of the present invention to provide an improved clutch mechanism for the transmission of rotary movement from a gear arrangement.
The object is achieved by a clutch mechanism according to claim 1 .
Preferred embodiments of the invention are given in the dependent claims.
According to the invention a clutch mechanism for transmission of rotary movement from a gear arrangement comprises a first gear member and a second gear member. The first gear member is rotatable about a longitudinal axis but axially fixed. The first gear member, upon rotation, is arranged for translatively moving a second gear member which is prevented from rotating. The clutch mechanism comprises a circumferential shoulder arranged on the second gear member and at least one resilient clutch finger or a number of resilient clutch fingers with respective inclined inner surfaces arranged on the first gear member. The shoulder is arranged for increasingly pressing against the inclined surfaces thereby flexing the clutch fingers outward when the shoulder reaches the clutch fingers in the course of its translation. The clutch mechanism further comprises a tube arranged around the clutch fingers, the tube having a number of internal longitudinal splines for engaging the flexed-out clutch fingers. Prior to being flexed out by the shoulder, the first gear member and its clutch fingers spin without engaging the longitudinal splines of the inner rear tube. When the clutch fingers are flexed out radially they engage with the longitudinal splines in the tube. Thus the rotation of the first gear member is transmitted and forwarded to another component when the second gear member has been advanced to a defined position. The clutch fingers may have respective external teeth protruding radially outwardly in order to provide a defined engagement with the longitudinal splines.
The internal longitudinal splines may be arranged in a manner to form a ratchet when engaged with the clutch fingers. This allows for continued rotation of the first gear member even after the tube has been rotated and hit a stop. By contrast a purely positive locking engagement between the clutch fingers and the longitudinal splines would stall the rotary movement as soon as the tube has hit the stop. Furthermore the ratchet style engagement provides an acoustic feedback for a user.
The clutch mechanism may be applied in an auto-injector for administering a dose of a liquid medicament, the auto-injector further comprising:
an elongate housing arranged to contain a syringe with a hollow needle and a bung for sealing the syringe and displacing the medicament, the elongate housing having a distal end and a proximal end with an orifice intended to be applied against an injection site, wherein the syringe is slidably arranged with respect to the housing, spring means capable of, upon activation, pushing the needle from a covered position inside the housing into an advanced position through the orifice and past the proximal end as well as operating the syringe to supply the dose of medicament, activating means arranged to lock the spring means in a pressurized state prior to manual operation and capable of, upon manual operation, releasing the spring means for injection.
In the context of this patent application the term proximal refers to the direction pointing towards the patient during an injection while the term distal refers to the opposite direction pointing away from the patient.
The spring means may be a torsion spring grounded at one end in the housing and at the other end in the first gear member, which is rotatable about a longitudinal axis but axially fixed. The first gear member, upon rotation, is arranged for translatively moving the second gear member. The second gear member is prevented from rotating and coupled to the bung in order to push it towards the proximal end. The first gear member is engaged with the activating means prior to manual operation in a manner to prevent rotation and disengaged from the activating means upon manual operation. The torsion spring is preferably loaded or wound during manufacturing of the auto-injector. When the torsion spring is released by operating the activating means the first gear member starts rotating.
The single torsion spring is used for both, inserting the needle and fully emptying the syringe. A major advantage of the torsion spring is that force is exerted on the bung and syringe in a smooth manner, whereas a conventional compression spring exhibits a rather abrupt force deployment which may spoil a glass syringe or other parts of the auto-injector. The clutch mechanism may be used to transmit rotary motion of the first gear member and forward it to release a needle shroud when the second gear member and the stopper have reached a defined position shortly before the syringe is emptied.
In a preferred embodiment an essentially tube-shaped needle shroud is arranged around the syringe in the housing. The needle shroud is slideable between at least a retracted position with the needle shroud almost hidden inside the housing and an advanced position with the needle shroud protruding from the proximal end and covering the hollow needle in its advanced position. The needle shroud is biased by a second spring means towards the advanced position and locked in the retracted position by a locking means. The locking means is releasable by rotary movement transmitted from the first gear member through the clutch mechanism which is engaged by the second gear member shortly before the second gear member is fully advanced during an injection stroke. Hence, once the dose is complete, the second spring means fires the needle shroud over the needle. This makes the device safer than an equivalent manual injection with respect to needlestick injuries.
In a particularly preferred embodiment an interlock mechanism is arranged for locking the activating means and preventing it from being manually operated. The interlock mechanism may be coupled to the needle shroud. The interlock mechanism may be releasable by pushing the needle shroud a small distance into the housing from the needle shroud's retracted position. Thus, the device cannot be used until the needle shroud is depressed. In normal use this occurs by pushing the device against an injection site, i.e. a patient's skin.
The activating means may be a trigger button laterally arranged at the housing and operable by being pressed transversally with respect to the longitudinal axis. Conventional auto-injectors have the trigger button at their distal end. The advantage of having the trigger button on the side is that the user is less likely to incur an injury should they be confused as to which end the needle will appear from.
The trigger button may have a locking pin engageable with at least one dog tooth provided on the first gear member for preventing rotation thereof in order to lock the spring means or keep it locked in the pressurized state. The dog teeth may be circumferentially arranged at the first gear member thus allowing for stopping the rotation and consequently the injection at any point in time by releasing the trigger button. The trigger button may therefore be biased by a return spring.
The locking means may have the shape of a bayonet fit between the needle shroud and an outer rear tube, which is arranged around the torsion spring. The needle shroud is guided in the housing in a manner to prevent relative rotation, e.g. by at least one spline engaging a respective slot in the housing. The outer rear tube is coupled to the clutch mechanism and may therefore be rotated by the torsion spring. The bayonet fit comprises a bayonet pin and a corresponding pin track arranged between the outer rear tube and the needle shroud. The pin may be held behind a track shoulder in order to hold the needle shroud in its retracted position. In order to release the needle shroud the outer rear tube is rotated by a small angle, thus turning the bayonet pin away from the track shoulder (or vice versa) and into a straight longitudinal part of the pin track. The needle shroud is now released and driven forward from the force of the second spring means, e.g. a compression spring when the auto-injector is removed from the injection site.
The second gear member may be a piston rod having an external lead screw thread. The piston rod may have an axial bore for slidably arranging the piston rod on a shaft attached to the housing. The axial bore and the shaft may have corresponding non-circular profiles in order to prevent relative rotation, e.g. square profiles or profiles with at least one spline or flat. The shaft may be directly or indirectly attached to the housing, e.g. by an end cap. However, the shaft has to be secured against rotation relative to the housing.
The first gear member may be a lead nut engaged with the external lead screw thread. The lead nut may have an internal lead screw thread or a pin guided in the external lead screw thread of the piston rod. Preferably the lead nut is equipped with at least one ball bearing in order to achieve a low friction contact.
In one embodiment the external lead screw thread may have a variable pitch. Thus, speed and force of the needle insertion and injection of the medicament may be adapted to user convenience and to the fact that the torque of the torsion spring is highest when it is fully wound or loaded, and lowest near the end of the injection stroke e.g. the pitch of the thread may be adapted to ensure a quick needle insertion and a relatively slow injection of the medicament in order to cause the least possible pain for the patient.
The interlock mechanism may comprise respective catches provided on the needle shroud and the trigger button. The catches may have the shape of hooks gearing into each other when the needle shroud is in its retracted position. As soon as the needle shroud is pushed in a small distance from the drawn back position the hook shaped catches are laterally shifted out of engagement allowing the trigger button to be operated. In order to allow the needle shroud to be pushed back from the retracted position a small clearance may be provided in the pin track behind the track shoulder.
In a preferred embodiment the syringe is arranged in a syringe carrier and supported by the syringe carrier at a proximal end. Supporting the syringe at its proximal end rather than at its flanges avoids damaging the syringe under load since the flanges are more fragile, in particular in a glass syringe. The syringe carrier is slidably arranged in the needle shroud. An abutment is provided in the needle shroud defining a maximum forward position of the syringe carrier. This allows for defining an injection depth, e.g. for a subcutaneous or intramuscular injection.
The tube of the clutch mechanism is preferably arranged as an inner rear tube arranged around the clutch fingers inside the torsion spring and attached to the outer rear tube at their distal ends.
In a preferred embodiment the internal longitudinal splines are arranged in a manner to form a ratchet when engaged with the clutch fingers. This allows for continued rotation of the lead nut even after the outer rear tube has been rotated and consequently the bayonet pin has hit the side of the longitudinal part of the pin track so the bung may be further forwarded until it bottoms out in the syringe so dead volume is avoided. This is particularly advantageous when using these types of autoinjectors with expensive medicaments. By contrast a purely positive locking engagement between the clutch fingers and the longitudinal splines would stall the rotary movement as soon as the bayonet pin hits the side of the longitudinal part of the pin track leaving residue medicament in the syringe. Furthermore the ratchet style engagement provides an acoustic feedback for the user announcing the upcoming end of the injection. During this time, e.g. ten seconds the user is asked to keep pressure on the injection site.
As the user withdraws the auto-injector from the injection site after the end of injection the needle shroud is pushed over the needle by the compression spring into its advanced position. A locking mechanism may be provided for locking the needle shroud in its advanced position so the needle cannot be re-exposed and needle stick injuries with the now contaminated needle are avoided.
The housing may have at least one viewing window for inspecting the syringe.
The term “medicament”, as used herein, means a pharmaceutical formulation containing at least one pharmaceutically active compound,
wherein in one embodiment the pharmaceutically active compound has a molecular weight up to 1500 Da and/or is a peptide, a proteine, a polysaccharide, a vaccine, a DNA, a RNA, a antibody, an enzyme, an antibody, a hormone or an oligonucleotide, or a mixture of the above-mentioned pharmaceutically active compound,
wherein in a further embodiment the pharmaceutically active compound is useful for the treatment and/or prophylaxis of diabetes mellitus or complications associated with diabetes mellitus such as diabetic retinopathy, thromboembolism disorders such as deep vein or pulmonary thromboembolism, acute coronary syndrome (ACS), angina, myocardial infarction, cancer, macular degeneration, inflammation, hay fever, atherosclerosis and/or rheumatoid arthritis,
wherein in a further embodiment the pharmaceutically active compound comprises at least one peptide for the treatment and/or prophylaxis of diabetes mellitus or complications associated with diabetes mellitus such as diabetic retinopathy,
wherein in a further embodiment the pharmaceutically active compound comprises at least one human insulin or a human insulin analogue or derivative, glucagon-like peptide (GLP-1) or an analogue or derivative thereof, or exedin-3 or exedin-4 or an analogue or derivative of exedin-3 or exedin-4.
Insulin analogues are for example Gly(A21), Arg(B31), Arg(B32) human insulin; Lys(B3), Glu(B29) human insulin; Lys(B28), Pro(B29) human insulin; Asp(B28) human insulin; human insulin, wherein proline in position B28 is replaced by Asp, Lys, Leu, Val or Ala and wherein in position B29 Lys may be replaced by Pro; Ala(B26) human insulin; Des(B28-B30) human insulin; Des(B27) human insulin and Des(B30) human insulin.
Insulin derivates are for example B29-N-myristoyl-des(B30) human insulin; B29-N-palmitoyl-des(B30) human insulin; B29-N-myristoyl human insulin; B29-N-palmitoyl human insulin; B28-N-myristoyl LysB28ProB29 human insulin; B28-N-palmitoyl-LysB28ProB29 human insulin; B30-N-myristoyl-ThrB29LysB30 human insulin; B30-N-palmitoyl-ThrB29LysB30 human insulin; B29-N-(N-palmitoyl-Y-glutamyl)-des(B30) human insulin; B29-N-(N-lithocholyl-Y-glutamyl)-des(B30) human insulin; B29-N-(ω-carboxyheptadecanoyl)-des(B30) human insulin and B29-N-(ω-carboxyheptadecanoyl) human insulin.
Exendin-4 for example means Exendin-4(1-39), a peptide of the sequence H-His-Gly-Glu-Gly-Thr-Phe-Thr-Ser-Asp-Leu-Ser-Lys-Gln-Met-Glu-Glu-Glu-Ala-Val-Arg-Leu-Phe-Ile-Glu-Trp-Leu- Lys-Asn-Gly-Gly-Pro-Ser-Ser-Gly-Ala-Pro-Pro-Pro-Ser-NH2.
Exendin-4 derivatives are for example selected from the following list of compounds:
H-(Lys)4-des Pro36, des Pro37 Exendin-4(1-39)-NH2, H-(Lys)5-des Pro36, des Pro37 Exendin-4(1-39)-NH2, des Pro36 [Asp28] Exendin-4(1-39), des Pro36 [IsoAsp28] Exendin-4(1-39), des Pro36 [Met(O)14, Asp28] Exendin-4(1-39), des Pro36 [Met(O)14, IsoAsp28] Exendin-4(1-39), des Pro36 [Trp(O2)25, Asp28] Exendin-4(1-39), des Pro36 [Trp(O2)25, IsoAsp28] Exendin-4(1-39), des Pro36 [Met(O)14 Trp(O2)25, Asp28] Exendin-4(1-39), des Pro36 [Met(O)14 Trp(O2)25, IsoAsp28] Exendin-4(1-39); or des Pro36 [Asp28] Exendin-4(1-39), des Pro36 [IsoAsp28] Exendin-4(1-39), des Pro36 [Met(O)14, Asp28] Exendin-4(1-39), des Pro36 [Met(O)14, IsoAsp28] Exendin-4(1-39), des Pro36 [Trp(O2)25, Asp28] Exendin-4(1-39), des Pro36 [Trp(O2)25, IsoAsp28] Exendin-4(1-39), des Pro36 [Met(O)14 Trp(O2)25, Asp28] Exendin-4(1-39), des Pro36 [Met(O)14 Trp(O2)25, IsoAsp28] Exendin-4(1-39), wherein the group -Lys6-NH2 may be bound to the C-terminus of the Exendin-4 derivative; or an Exendin-4 derivative of the sequence H-(Lys)6-des Pro36 [Asp28] Exendin-4(1-39)-Lys6-NH2, des Asp28 Pro36, Pro37, Pro38Exendin-4(1-39)-NH2, H-(Lys)6-des Pro36, Pro38 [Asp28] Exendin-4(1-39)-NH2, H-Asn-(Glu)5des Pro36, Pro37, Pro38 [Asp28] Exendin-4(1-39)-NH2, des Pro36, Pro37, Pro38 [Asp28] Exendin-4(1-39)-(Lys)6-NH2, H-(Lys)6-des Pro36, Pro37, Pro38 [Asp28] Exendin-4(1-39)-(Lys)6-NH2, H-Asn-(Glu)5-des Pro36, Pro37, Pro38 [Asp28] Exendin-4(1-39)-(Lys)6-NH2, H-(Lys)6-des Pro36 [Trp(O2)25, Asp28] Exendin-4(1-39)-Lys6-NH2, H-des Asp28 Pro36, Pro37, Pro38 [Trp(O2)25] Exendin-4(1-39)-NH2, H-(Lys)6-des Pro36, Pro37, Pro38 [Trp(O2)25, Asp28] Exendin-4(1-39)-NH2, H-Asn-(Glu)5-des Pro36, Pro37, Pro38 [Trp(O2)25, Asp28] Exendin-4(1-39)-NH2, des Pro36, Pro37, Pro38 [Trp(O2)25, Asp28] Exendin-4(1-39)-(Lys)6-NH2, H-(Lys)6-des Pro36, Pro37, Pro38 [Trp(O2)25, Asp28] Exendin-4(1-39)-(Lys)6-NH2, H-Asn-(Glu)5-des Pro36, Pro37, Pro38 [Trp(O2)25, Asp28] Exendin-4(1-39)-(Lys)6-NH2, H-(Lys)6-des Pro36 [Met(O)14, Asp28] Exendin-4(1-39)-Lys6-NH2, des Met(O)14 Asp28 Pro36, Pro37, Pro38 Exendin-4(1-39)-NH2, H-(Lys)6-desPro36, Pro37, Pro38 [Met(O)14, Asp28] Exendin-4(1-39)-NH2, H-Asn-(Glu)5-des Pro36, Pro37, Pro38 [Met(O)14, Asp28] Exendin-4(1-39)-NH2, des Pro36, Pro37, Pro38 [Met(O)14, Asp28] Exendin-4(1-39)-(Lys)6-NH2, H-(Lys)6-des Pro36, Pro37, Pro38 [Met(O)14, Asp28] Exendin-4(1-39)-(Lys)6-NH2, H-Asn-(Glu)5 des Pro36, Pro37, Pro38 [Met(O)14, Asp28] Exendin-4(1-39)-(Lys)6-NH2, H-Lys6-des Pro36 [Met(O)14, Trp(O2)25, Asp28] Exendin-4(1-39)-Lys6-NH2, H-des Asp28 Pro36, Pro37, Pro38 [Met(O)14, Trp(O2)25] Exendin-4(1-39)-NH2, H-(Lys)6-des Pro36, Pro37, Pro38 [Met(O)14, Asp28] Exendin-4(1-39)-NH2, H-Asn-(Glu)5-des Pro36, Pro37, Pro38 [Met(O)14, Trp(O2)25, Asp28] Exendin-4(1-39)-NH2, des Pro36, Pro37, Pro38 [Met(O)14, Trp(O2)25, Asp28] Exendin-4(1-39)-(Lys)6-NH2, H-(Lys)6-des Pro36, Pro37, Pro38 [Met(O)14, Trp(O2)25, Asp28] Exendin-4(S1-39)-(Lys)6-NH2, H-Asn-(Glu)5-des Pro36, Pro37, Pro38 [Met(O)14, Trp(O2)25, Asp28] Exendin-4(1-39)-(Lys)6-NH2;
or a pharmaceutically acceptable salt or solvate of any one of the afore-mentioned Exedin-4 derivative.
Hormones are for example hypophysis hormones or hypothalamus hormones or regulatory active peptides and their antagonists as listed in Rote Liste, ed. 2008, Chapter 50, such as Gonadotropine (Follitropin, Lutropin, Choriongonadotropin, Menotropin), Somatropine (Somatropin), Desmopressin, Terlipressin, Gonadorelin, Triptorelin, Leuprorelin, Buserelin, Nafarelin, Goserelin.
A polysaccharide is for example a glucosaminoglycane, a hyaluronic acid, a heparin, a low molecular weight heparin or an ultra low molecular weight heparin or a derivative thereof, or a sulphated, e.g. a poly-sulphated form of the above-mentioned polysaccharides, and/or a pharmaceutically acceptable salt thereof. An example of a pharmaceutically acceptable salt of a poly-sulphated low molecular weight heparin is enoxaparin sodium.
Pharmaceutically acceptable salts are for example acid addition salts and basic salts. Acid addition salts are e.g. HCl or HBr salts. Basic salts are e.g. salts having a cation selected from alkali or alkaline, e.g. Na+, or K+, or Ca2+, or an ammonium ion N+(R1)(R2)(R3)(R4), wherein R1 to R4 independently of each other mean: hydrogen, an optionally substituted C1-C6-alkyl group, an optionally substituted C2-C6-alkenyl group, an optionally substituted C6-C10-aryl group, or an optionally substituted C6-C10-heteroaryl group. Further examples of pharmaceutically acceptable salts are described in “Remington's Pharmaceutical Sciences” 17. ed. Alfonso R. Gennaro (Ed.), Mark Publishing Company, Easton, Pa., U.S.A., 1985 and in Encyclopedia of Pharmaceutical Technology.
Pharmaceutically acceptable solvates are for example hydrates.
Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will become more fully understood from the detailed description given herein below and the accompanying drawings which are given by way of illustration only, and thus, are not limitive of the present invention, and wherein:
FIG. 1 is a perspective view of an auto-injector with a needle shroud and a lateral trigger button,
FIG. 2 is a longitudinal section of the auto-injector in a prior to use state,
FIG. 3 is a perspective detail view of the longitudinal section of FIG. 2 with the needle shroud and the trigger button interlocked,
FIG. 4 is a perspective detail view with the trigger button released from the interlock by pressing the needle shroud against an injection site,
FIG. 5 is a perspective detail view with the trigger button pressed,
FIG. 6 is a longitudinal section of the auto-injector with a syringe and an injection needle advanced in order to pierce a patient's skin,
FIG. 7 is a detail view of the longitudinal section of FIG. 6 ,
FIG. 8 is a longitudinal section of the auto-injector with a piston rod advancing a bung in order to expel a liquid medicament from the syringe,
FIG. 9 is a detail view of FIG. 8 with a clutch mechanism,
FIG. 10 shows perspective views of two alternative clutch mechanisms,
FIG. 11 is a perspective view of the auto-injector with a bayonet fit between the needle shroud and an outer rear tube, the needle shroud prevented from moving forward,
FIG. 12 is a perspective view of the auto-injector with the bayonet fit, the outer rear tube rotated in order to allow the needle shroud to move forward,
FIG. 13 is a perspective view of the auto-injector with the bayonet fit, the needle shroud pushed forward by means of a bias spring, and
FIG. 14 is a longitudinal section of the auto-injector with the needle shroud fully advanced and locked in forward position in order to protect the needle.
Corresponding parts are marked with the same reference symbols in all figures.
DETAILED DESCRIPTION
FIG. 1 shows a perspective view of an auto-injector 1 with an elongate housing 2 and a needle shroud 3 for protecting a needle (not shown). A lateral trigger button 4 may be transversally pressed in order to trigger an automatic injection. The trigger button 4 is interlocked with the needle shroud 3 so it cannot be pressed until the needle shroud 3 is pushed into the housing 2 by placing it on an injection site, e.g. a patient's skin and applying pressure. The needle shroud 3 has longitudinal splines 5 engaged in corresponding grooves in the housing 1 for preventing relative rotation of the needle shroud 3 with respect to the housing 1 . A viewing window 6 allows for viewing and inspecting a syringe held in the auto-injector 1 .
FIG. 2 shows a longitudinal section of the auto-injector 1 in a prior to use state. A syringe 7 is partially surrounded and supported at a front end by a syringe carrier 8 . Attached at the front end of the syringe 7 is a hollow needle 9 for piercing a patient's skin and delivering a liquid medicament M stored inside the syringe 7 . Near a back end of the syringe 7 a bung 10 is arranged for sealing the back end. The bung 10 may be advanced by a piston rod 11 in order to expel the medicament M from the syringe 7 . The syringe carrier 8 is slidably arranged inside the needle shroud 3 . The needle shroud 3 is biased by a compression spring 12 towards a proximal end P. A bayonet fit (shown in FIG. 11 ) between the needle shroud 3 and an outer rear tube 13 serves for holding the needle shroud 3 in position against the bias of the compression spring 12 prior to use.
A torsion spring 14 is arranged inside the outer rear tube 13 and with one end attached to a distal end D of the housing 2 so torque from the torsion spring 14 is reacted into the housing 2 . The other end of the torsion spring 14 is coupled to a lead nut 15 which is rotatably mounted around the piston rod 11 . The piston rod 11 has an external lead screw thread 16 engaged with the lead nut 15 . The lead nut 15 is equipped with at least one ball bearing 17 for this engagement. It could alternatively have at least one pin. In the prior to use state shown in FIG. 2 the lead nut 15 is biased by the torsion spring 14 but kept from rotating by a locking pin 18 arranged at the trigger button 4 engaged with a dog tooth 19 arranged at the lead nut 15 . An inner rear tube 20 is arranged inside the torsion spring 14 and around the piston rod 11 and part of the lead nut 15 . The piston rod 11 is guided along a shaft 21 arranged in an axial bore of the piston rod 11 . The axial bore and the shaft 21 both have a non-circular profile in order to keep the piston rod 11 from rotating, e.g. a square profile or a profile with at least one spline or flat. The shaft 21 is attached to an end cap 22 arranged at the distal end D of the auto-injector 1 .
A protective needle shield (not shown) may be provided which has to be removed prior to use by a user resulting in the situation of FIG. 1 . In this situation the needle 9 is a safe distance back within the needle shroud to protect the user from accidental needlestick injuries.
FIG. 3 shows a perspective detail view of the longitudinal section of FIG. 2 with the needle shroud 3 and the trigger button 4 interlocked by catches 24 , 25 provided at the needle shroud 3 and the trigger button 4 , respectively.
In order to prepare for an injection the user pushes the proximal end P of the auto-injector 1 against the injection site. Thus the needle shroud 3 is moved into the auto-injector 1 by a small distance big enough to release the interlocking catches 24 , 25 from each other. This situation is shown in FIG. 4 . The compression spring 12 opposes the motion of the needle shroud 3 but is specified such that its spring rate and preload are low enough to feel natural for the user. The trigger button 4 may now be operated.
FIG. 5 shows the distal end of the trigger button 4 being pressed thus rotating the trigger button 4 about a trigger pivot 26 in the housing 2 , raising the proximal end of the trigger button 4 and moving the locking pin 18 out of the engagement with the dog tooth 19 of the lead nut 15 . Thus the lead nut 15 is released and torque from the torsion spring 14 causes the lead nut 15 to rotate. Since the lead nut 15 abuts against a thrust face 27 in the housing 2 it is kept from moving in distal direction D due to the load applied to the piston rod 11 while rotating.
Instead, as shown in FIG. 6 , the piston rod 11 , kept from rotating by the shaft 21 , is pushed forward in proximal direction P due to the engagement of the lead nut 15 and the lead screw thread 16 . The advancing piston rod 11 pushes against the bung 10 which in turn advances the syringe 7 by virtue of the friction between the bung 10 and the syringe wall and due to the thin fluid channel inside the hollow needle 9 opposing the displacement of the medicament M. The advancing syringe 7 also causes the needle 9 to protrude beyond the proximal end P of the auto-injector 1 into the injection site, e.g. the patient's skin. Since the syringe 7 is supported at its proximal end by an orifice of the syringe carrier 8 the syringe carrier 8 is also advanced with the syringe 7 until the syringe carrier 8 abuts against an abutment in the needle shroud 3 . This contact sets the injection depth relative to the needle shroud 3 .
FIG. 7 is a detail view of the longitudinal section of FIG. 6 .
After the syringe carrier 8 has hit the abutment of the needle shroud 3 the syringe 7 is kept from advancing further. With the lead nut 15 still rotating and pushing the piston rod 11 the bung 10 overcomes the friction and the hydraulic resistance of the medicament M and advances inside the syringe 7 thereby displacing the medicament M and delivering it through the fluid channel of the hollow needle 9 into or through the patient's skin. This situation is shown in FIG. 8 .
FIG. 8 shows the piston rod 11 and the bung 10 almost fully advanced and the syringe 7 almost entirely emptied but for a small residue. Referring now to FIGS. 9 and 10 a and b showing different detail views of the cut-out marked in FIG. 8 , just before the bung 10 bottoms out in the syringe 7 a shoulder 28 on the distal end of the piston rod 11 behind the lead screw thread 15 is pushed into clutch fingers 29 on the distal end of the lead nut 15 thereby bending the clutch fingers 29 radially outward. Each clutch finger 29 has an external tooth 30 which now engages with a respective internal longitudinal spline 31 provided in the proximal end of the inner rear tube 20 , causing the inner rear tube 20 to rotate along with the lead nut 15 . The splines 31 are arranged in a ratchet manner in FIG. 10 a . FIG. 10 b shows an alternative embodiment with rounded finger teeth 30 . In both embodiments ( FIGS. 10 a and 10 b ) the clutch mechanism is arranged to let the clutch fingers 29 generate enough torque on the longitudinal splines 31 to partially rotate the outer rear tube 13 to release a bayonet fit described below in FIG. 11 . However the torque generated has to be low enough to let the lead nut 15 continue rotating with the spring arms jumping over the splines 31 and making a rattling noise indicating that the injection has been nearly finished. The inner rear tube 20 is coupled with the outer rear tube 13 near the distal end D of the auto-injector 1 (cf. FIG. 8 ). Thus the outer rear tube 13 is also rotated. The outer tube 13 has a circumferential slot (not illustrated) to allow the distal end of the torsion spring to pass through to the housing 2 for grounding the torsion spring 14 . The circumferential slot has to be long enough to allow a partial rotation of the outer rear tube 13 in order to disengage the bayonet fit described below in FIG. 11 .
FIG. 11 shows a perspective view of the auto-injector 1 just before the engagement of the clutch fingers 29 with the internal longitudinal splines 31 . The bayonet fit between a pin 32 of the needle shroud 3 and a pin track 33 of the outer rear tube 13 is still in a state with the pin 32 behind a track shoulder 34 so the needle shroud 3 would be held in position against the bias of the compression spring 12 if the still depressed needle shroud 3 was released. A small axial clearance behind the track shoulder 34 allows the needle shroud 3 to be pushed in distal direction D just enough to disengage the interlock between the button 4 and the needle shroud 3 as described above.
When the clutch fingers 29 are engaged with the internal longitudinal splines 31 the outer rear tube 13 is rotated so as to disengage the bayonet fit by the pin 32 coming clear of the track shoulder 34 so the needle shroud 3 may be pushed forward by the compression spring 12 (see FIG. 12 ). At this point the user is asked to keep pressure with the auto-injector 1 at the injection site for a short period of time, e.g. ten seconds. During this time the lead nut 15 is still rotating and forwarding the piston rod 11 and bung 10 until the bung 10 bottoms out at the proximal end of the syringe 7 thereby virtually entirely displacing the rest of the medicament M from the syringe 7 .
As the user withdraws the auto-injector 1 from the injection site the needle shroud 3 is pushed over the needle 9 in proximal direction P by the compression spring 12 . This situation is shown in FIGS. 13 and 14 . A locking mechanism may be provided to lock the needle shroud 3 in this extended needle protection position in order to prevent further exposure of the needle. The locking mechanism may be a unidirectional barb or a similar means known to those skilled in the art. | The invention relates to a clutch mechanism for the transmission of a rotary movement from a gear arrangement comprising a first gear member and a second gear member. The first gear member is rotatable about a longitudinal axis but axially fixed wherein the first gear member, upon rotation, is arranged for translatively moving a second gear member which is prevented from rotating. The clutch mechanism comprises a circumferential shoulder arranged at the second gear member and at least one or a number of resilient clutch fingers with respective inclined inner surfaces arranged at the first gear member, the shoulder arranged for increasingly pressing against the inclined surfaces thereby flexing the clutch fingers outward when the shoulder reaches the clutch fingers in the course of its translation. The clutch mechanism further comprises tube arranged around the clutch fingers, the tube having a number of internal longitudinal splines for engaging the flexed-out clutch fingers. | 0 |
FIELD OF THE INVENTION
The present invention relates to a stabilizing tool used in rock drilling and more particularly to a roller stabilizer for stabilizing the drilling action of a rock bit.
BACKGROUND OF THE INVENTION
The use of stabilizer tools for stabilizing the action of a rotary rock bit and the attached drill string is well know. An example of such a tool may be seen from U.S. Pat. No. 4,013,325 granted to Rear on Mar. 22, 1977. The stabilizer fits between the rock bit and the drill string and consists of a cylindrical body with typically three or more carbide studded rollers set into the stabilizer body and arranged around its circumference. The rollers are axially aligned with the body and when set in place, protrude radially outwardly from the stabilizer's outer surface. The rollers contact the bore hole wall and help prevent the bit from "walking" to produce a straighter hole. The rollers also grind away overhangs or loose rock to create a smoother bore. The rollers are driven by frictional contact with the hole wall and therefore counter-rotate relative to the drill bit.
Drilling fluid, which may be a gas (pressurized air) or a liquid, passes axially through the stabilizer to the rock bit and carriers the cuttings back to the surface in the annulus between the bore hole and the drill string. Some or all of the drilling fluid passing through the stabilizer is directed through the shafts that rotatably support the rollers in the stabilizer to cool the rollers. Lubricant entrained or suspended in the drilling fluid is also delivered in this way to some of the exposed bearing surfaces between the shafts and rollers.
Stabilizers currently in use are prone to excessive wear. This necessitates costly repairs and maintenance, causes down time and ultimately leads to disposal of the tool when beyond repair. Wear is aggravated by the ingress of dust and cuttings into the rollers. One of the results of this wear is that drilling fluid diverted through the rollers for cooling purposes begins to escape into the bore hole annulus. If sufficient fluid begins to leak, there will be a loss of circulation at the bit so that the cuttings are no longer carried away efficiently. More importantly, rotary rock bits cannot function properly without adequate air pressure in the bit and a loss of air from the stabilizer will negatively affect the bit's performance. Drilling must then be stopped for stabilizer repair or replacement.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to obviate and mitigate from the disadvantages of prior stabilizers.
It is a further object of the present invention to better seal the rollers to reduce wear, increase tool life, facilitate lubrication of the rollers, and to better prevent loss of drilling fluid.
According to the present invention, then, there is provided a stabilizing tool for drilling having a plurality of roller assemblies disposed in pockets about the surface of the tool, the assemblies each including at least one rotatable grinding roller disposed for frictional contact with the walls of a bore hole being drilled, said tool comprising a fluid passageway formed axially therethrough for the flow of drilling fluid, said passageway having a first zone wherein the pressure of said fluid is relatively high and a second zone wherein said pressure is relatively low; and means placing said passageway in fluid communication with the interior of respective ones of said rollers, said means including first conduit means providing fluid communication between said zone of relatively high pressure and the interior of said roller for the ingress of said fluid to said interior, and second conduit means providing fluid communication between the interior of said roller and said zone of relatively low pressure for the egress of said fluid back to said passageway.
According to another aspect of the present invention, there is also provided a roller assembly for a stabilizing tool used for drilling, the assembly comprising a roller; a shaft to rotatably support said roller thereon; a sealed annular space between said roller and shaft; and a flow path for fluid into and then out from said sealed annular space for cooling of said roller.
According to yet another aspect of the present invention, there is also provided a roller assembly for a stabilizing tool used for drilling, said tool having a pocket formed therein for each roller assembly, said roller comprising a roller; a shaft to rotatably support said roller thereon; and sleeve means adapted to fit over and partially circumferentially enclose said roller and shaft, leaving said roller partially exposed for frictional contact with the surface of a bore hole being drilled, said sleeve means enclosing enough of said roller to prevent lateral separation of said roller from said sleeve means.
According to yet another aspect of the present invention, there is also provided a method of cooling a grinding roller disposed on the surface of a stabilizer tool used in the drilling of bore holes, the method comprising the steps of rotatably mounting said roller on a shaft so that an annular space is formed between said roller and shaft; and directing a cooling fluid into and then out from said annular space.
According to yet another aspect of the present invention, there is also provided a method of cooling a grinding roller disposed on the surface of a stabilizer tool used in the drilling of bore holes, the roller being rotatably mounted on a shaft supported in the tool, the method comprising the steps of forming a passageway through said stabilizer tool for the flow of drilling fluid; controlling the flow of said fluid through said passageway to establish a zone of relatively higher fluid pressure and a zone of relatively lower fluid pressure; creating a fluid tight annular space between said roller and said shaft; and establishing fluid communication between said zone of relatively higher fluid pressure and said annular space for the ingress of said fluid into said annular space, and fluid communication between said zone of relatively lower fluid pressure and said annular space for the egress of said fluid from said annular space.
BRIEF DESCRIPTION OF THE DRAWINGS
Preferred embodiments of the present invention will now be described in greater detail and will be better understood when read in conjunction with the following drawings, in which:
FIG. 1 is a schematical partially cross-sectional view of a prior art stabilizer illustrating the delivery of drilling fluid and entrained lubricant to the stabilizer rollers;
FIG. 2 is a perspective view of the present stabilizer with the rollers installed and clamped in place;
FIG. 3 is a side elevational cross-sectional view of the stabilizer body along the longitudinal axis thereof;
FIG. 4 is an end elevational, cross-sectional view of the stabilizer body of FIG. 3 along the line A--A;
FIG. 5 is a plan view of a roller pocket formed into the stabilizer body of FIG. 3;
FIG. 6 is a side elevational, cross-sectional view of a roller shaft;
FIG. 7 is a bottom plan view of the end of the shaft of FIG. 6 looking in the direction of arrow B;
FIG. 8 is an end elevational view of the end of the shaft shown in FIG. 7;
FIG. 9 is a side elevational, cross-sectional view of a stabilizer roller;
FIG. 10 is a side elevational cross-sectional view of the stabilizer body enlarged to show the assembly with a roller;
FIG. 11 is a side elevational, cross-sectional view of a split roller sleeve for supporting the roller of FIG. 9 in the stabilizer body;
FIG. 12 is an end elevational view of one of the sleeves of FIG. 11 looking in the direction of arrow C;
FIG. 13 is an end elevational view of a roller clamp;
FIG. 14 is a plan view of the clamp of FIG. 13; and
FIG. 15 is a cross-sectional view of a wear ring.
DETAILED DESCRIPTION
With reference to FIG. 1, a conventional stabilizer 200 is shown connected uphole of a rotary rock bit 210. The bit and stabilizer are shown separated by a tubular sub 205 but the use of a sub is optional and the bit and stabilizer are often threaded together directly.
Typically, three or more rollers 215 are rotatably supported in pockets 220 formed in the stabilizer body 201 with the rollers protruding beyond the body's outer surface. The outer surface of each roller is studded with carbide buttons 225 that frictionally engage the wall 250 of the bore hole which causes the rollers to rotate in the direction opposite rotation of the drill bit. Each roller is supported for rotation on a hollow shaft 230. The ends of the shaft are received into cylindrical sockets 231 formed into axially opposite ends of pocket 220. The interior of the hollow shafts are placed in fluid communication with the axial passageway 240 formed through the stabilizer for the flow of drilling fluid, which is usually compressed air. The drilling fluid, which may include an entrained airborne lubricant for the rock bit, is thusly directed through the roller assemblies for cooling and lubrication.
Typically, there is little or no sealing between the rollers and the shafts, or if there is sealing, it's relatively short lived and the inevitable ingress of dust and cuttings results in wear between the roller and shaft and between the shaft ends and sockets 231. As the wear increases, drilling fluid escapes through and around the roller assemblies into the bore hole annulus, increasing to the point where the air pressure at the bit is inadequate to sustain bit performance and to carry away the cuttings effectively.
We are proposing an improved stabilizer with greater sealing between the roller and shaft. This permits the use of bearings and wear sleeves between the roller and shaft. The sealing and other features of the stabilizer to be described below results in a greater delta pressure across the roller assemblies to more effectively draw cooling fluid and lubricant into and through the assembly for greater cooling and lubrication of the bearings. This improves roller life and significantly increases each stabilizer's footage prior to the need for repair and/or replacement. As well, in the event of even catastrophic roller failure, it is anticipated that fluid loss will still be insufficient to badly affect bit performance.
Reference will now be made to FIG. 2 and subsequent Figures in which like reference numerals have been used to identify like elements. As seen in FIG. 2, the present stabilizer 1 comprises a one piece tubular body 5 internally box threaded at its down hole end 3 for connection to a rock bit and externally box threaded at its uphole end 4 for connection to the drill string (not shown). An axial passageway 40 extends through the stabilizer from one end to the other for the flow of drilling fluid and lubricant usually in the direction of Arrow A. In the embodiment shown, the stabilizer includes three carbide-studded rotatable rollers 15 spaced at 120° intervals in pockets 20. Both ends 19 of each roller are tapered or chamfered to facilitate insertion and withdrawal of the tool from the bore hole.
FIG. 3 is a cross-sectional view of the stabilizer body 5 along its major longitudinal axis with the roller assemblies removed. As will be seen, passageway 40 narrows in the area radially beneath pockets 20, providing more clearance for the required depth of these pockets and creating a zone in which the pressure of the drilling fluid is lower than in the wider section of the passage immediately uphole of the pockets. The pockets themselves, as best seen from FIGS. 3, 4 and 5, are substantially rectangular openings formed into the stabilizer body, with each pocket including at its opposite ends a rectangular notch 42 flanked by shoulders 43. Fluid passageways or conduits 45 and 46 extend diagonally between the lower corners of respective notches 42 and passageway 40. More specifically, conduit 45 at the uphole side of pocket 20 extends from notch 42 to the wider diameter, higher pressure (and lower fluid velocity) portion of passage 40, and conduit 46 extends from notch 42 at the downhole side of the pocket to the narrower, lower pressure (and higher fluid velocity) region of passage 40, As will be described below, this creates a delta pressure across the roller assembly which more effectively draws fluid and lubricant into and through the rollers.
Each pocket as aforesaid is adapted to support a roller assembly comprising in part a roller 15 (FIG. 9) and a shaft 30 (FIG. 6) that rotatably supports the roller. The roller shaft will be described first with reference to FIGS. 6, 7 and 8. Each shaft is symmetrical from one of its ends to the other and only one end therefore will be described in detail.
With reference to FIG. 6, it will be seen that unlike prior art roller shafts, shaft 30 is not hollow from one end all the way through to its other end. Instead, a passage 31 is formed only partially through the shaft, and fluid communication to the shaft's outer surface is provided by means of a plurality of ventilation holes 33. As will be described below, these holes will direct drilling fluid into an annulus 56 (FIG. 10) between the shaft and roller, and the holes at the downhole end of the shaft will exhaust this fluid back to main passageway 40. Axially inwardly of holes 33, at least one but preferably a pair of bearing races 35 is formed into the shaft's outer surface for ball bearings, and axially outwardly of the holes, the outer surface 32 of the shaft is polished for fluid sealing contact with one or more O-rings and a wear sleeve that will be described below.
With particular reference to FIGS. 7 and 8, the end 38 of shaft 30 is squared off for a close fit into notch 42 at the end of pocket 20. This prevents the shaft from rotating relative to the stabilizer body, and effectively eliminates wear between the shaft and the body. A notch 36 is formed into the squared end of the shaft to provide fluid communication between diagonal conduits 45/46 and passage 31.
With reference to FIGS. 9 and 10, roller 15 is sized and adapted to fit over shaft 30 so that there is an annular space 56 remaining between the two. As with the shaft, each roller is substantially symmetrical from one end to the other, and only one end will therefore be described in detail. As shown, the roller is hollow all the way through to provide clearance for shaft 30. Fluid-tight sealing between the roller and shaft is provided by means of one or more O-rings 9 located at the outer end of the roller by circumferential grooves 12 in the roller's inner surface so that the O-ring or rings seal against the polished outer surface 32 of the shaft. Inwardly of the O-rings, another circumferential groove 7 in the roller locates a composite wear sleeve 6 that also bears against polished shaft surface 32. Inwardly of the wear sleeve, at least one but preferably a pair of bearing races 35 are formed to be radially opposite the races 35 formed in the shaft. An opening 19 from the roller's outer surface to each race is formed so that after the roller is assembled on the shaft, ball bearings 23 can be dropped into the races until full. These openings are closed by means of threaded fasteners for example (not shown) that can then be welded shut. Holes 33 in the shaft for the flow of the drilling fluid and lubricant open into the annulus 56 between wear sleeve 6 and bearings 23. The normal direction of fluid flow is indicated by Arrows B.
It will be understood that reference to the use of ball bearings 23 and associated races 35 is exemplary in nature. Bearing support alternatives can include the use of sleeve or needle-type bearings, friction bearings or any other suitable alternatives that will occur to those skilled in the art.
Each of rollers 15 may include one or more helical threads 29 machined into its inner surface between the two sets of bearing races 35. This machined spiral creates a turbine effect that assists or could assist in distributing drilling fluid and lubricant from the uphole conduit 45, through bearings 23, into the sealed annulus 56 between the roller and shaft and then in exhausting the mixture through the downhole passage 46 back towards the rock bit. In one embodiment constructed by the applicants, threads 29 comprise 3 to 4 starts of 0.080" depth threads with preferably a wide spacing between the threads in the range, for example, of 0.100" to 0.250".
Before installing the shaft and roller assemblies into pockets 20, each assembly is first assembled with a split roller sleeve 60 and wear rings 70 as shown most clearly in FIG. 10. Rings 70 (see also FIG. 15), which will normally be metal, fit over respective ends of shaft 30 and are spotted in place by abutment with shoulders 34 machined into the shaft's outer surface. The two halves of split ring 60 are then assembled together to form a cradle for the roller assembly. Apertures 63 at the ends of the roller sleeve partially encircle wear rings 70, and the sleeve's body partially encircles the roller assembly. As seen best from the end view of FIG. 12, roller sleeve 60 is shaped to concentrically enclose more than half of the circumference of the wear rings and the roller assembly to prevent separation. The squared ends of shaft 30 extend axially from the completed assembly of the roller sleeve and the roller. This completed assembly is inserted into one of pockets 20 for a conformable fit thereinto as best seen from FIG. 2. When inserted into the pocket, the protruding squared ends of shaft 30 are received into notches 42. To lock the roller assemblies into the stabilizer, the ends of the shaft fitted into notches 42 are sealed off with metal clamps 75 shaped as shown in FIGS. 13 and 14.
The lower surface of each clamp includes a notch 76 to engage the portion of the squared end of the shaft that protrudes above notch 42. Flanking the notch on either side are a pair of feet 78 that abut against shoulders 43 (FIG. 4). The upper surface 79 of the clamp has the same curvature as the contiguous outer surface of the stabilizer body. As best seen from FIGS. 3 and 10, a portion 81 of the stabilizer body around the edge of the clamp is machined away to form a gutter for a weldment permanently connecting clamps 75 to the stabilizer body. The weldment can be polished for a seamless surface between the clamps and the body.
Sleeves 60 serve a number of purposes. They hold the rollers and wear rings 70 in place even in the event of shaft failure whereas otherwise the rollers in particular could eject from the stabilizer to jam the tool string in the hole. The sleeves, which are dimensioned so that the annular distance 62 to the rollers is constant, limit the ingress of cuttings into the area immediately surrounding the rollers. When replacement is eventually required the old roller and sleeve combination is removed and a new assembly inserted without the need to re-machine pockets 20. In addition, wear rings 70 act as thrust bearings for the rollers, particularly in the event that bearings 23 or races 35 begin to wear.
In operation, when the stabilizer is assembled and inserted between the rotary bit and the drill string, rollers 15 will rotate at speeds of approximately 300 to 350 rpm depending upon the rate of rotation of the rock bit. Drilling fluid and entrained lubricant will be drawn into uphole conduit 45, through notch 42 and into passage 31 in shaft 30. The mixture will then pass through holes 33 into annulus 56 between the roller and the shaft to pressurize the annulus and deliver lubricant and drilling fluid to cool and lubricate ball bearings 23 and other bearing surfaces between the roller and shaft. The drilling fluid/lubricant mixture is then exhausted through the downhole set of holes 33, through passage 31, notch 42, conduit 46 and back to axial passage 40 for flow through the remainder of the stabilizer. With conduit 45 drawing from a relatively low velocity, high pressure zone of passage 40, and conduit 46 exhausting into a relatively high velocity, low pressure zone of passage 40, a venturi-type effect is created that positively and continuously draws fluid and lubricant into the roller assembly and then exhausts the mixture downstream. The anticipated turbine effect from threads 29 should improve the distribution of the fluid/lubricant mixtures through the annulus and particularly across bearings 23. Roller life is substantially enhanced by the use of bearings and wear sleeves between the roller and shaft and the reliable delivery of lubricant and coolant to these components. The pressure developed in the annulus between the roller and shaft is contained by the O-rings and the anchoring of the shafts against rotation helps prevent the kinds of wear that would otherwise result in the escape of drilling fluid through the rollers into the bore hole annulus.
In one embodiment constructed by the applicant, stabilizer body 5 has been machined from 4140-4145 heat stress relieved tool steel. Shafts 30 have been made from AMS 6418 steel available commercially as HYTUFF™, and rollers 15 have been made from hardened steel available commercially as EN30B.
As will be appreciated, as the rollers are designed to make constant contact with the bore hole wall, the flow of cuttings back to the surface can be impeded. This causes the cuttings to swirl around the bottom section of the stabilizer downhole of the rollers until ground small enough to pass over the rollers. This swirling action results in severe wear on the stabilizer in the zone between the bit and the rollers.
To alleviate this problem, we have introduced longitudinally extending flutes 90 into the outer surface of the stabilizer body. These flutes create channels for the cuttings to more easily bypass the rollers to achieve longer body life and also less restriction on the velocity of the return flow of the cuttings to the surface.
The above-described embodiments of the present invention are meant to be illustrative of preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications, which would be within the scope of the present invention. The only limitations to the scope of the present invention are set out in the following appended claims. | An improved stabilizing tool includes a body with a pocket, and a roller rotatably disposed in the pocket. The body includes a fluid passageway formed axially therethrough. The passageway has a first zone wherein the pressure of the fluid is relatively high and a second zone wherein the pressure is relatively low. A first conduit provides fluid communication between the first zone and an interior of the roller for the ingress of fluid to the interior, and a second conduit provides fluid communication between the interior of the roller and the second zone for the egress of the fluid back to the fluid passageway. | 4 |
RELATED APPLICATION
[0001] This application is a non-provisional application claiming benefit under 35 U.S.C. § 119 (e) of U.S. Provisional Application No. 60/488,247, entitled “Enantiospecific catalysts prepared by chiral deposition,” filed Jul. 18, 2003, which is incorporated herein by reference.
U.S. GOVERNMENT RIGHTS
[[0002]] This invention was made with the support of the U.S. Government under National Science Foundation Grants DMR-0071365, DMR-0076338, and CHE-024324. The Government has certain rights in the invention.
BACKGROUND OF THE INVENTION
[0003] Chirality is ubiquitous in Nature. One enantiomer of a molecule is often physiologically active, while the other enantiomer may be either inactive or toxic. For example, S-ibuprofen is as much as 100 times more active than R-ibuprofen. R-thalidomide is a sedative, but S-thalidomide causes birth defects. Worldwide sales of chiral drugs in single enantiomeric dosage forms reached $133 billion in 2000, growing at an annual rate of 13%. See, S. C. Stinson, Chiral Pharmaceuticals, Chem. Eng. News, 79(40), 79 (2001). The industrial synthesis of chiral compounds presently utilizes solution-phase, homogeneous catalysts and enzymes.
[0004] There have been elegant experiments directed at the production of enantiospecific heterogeneous catalysts in which achiral surfaces are modified by chiral molecules in order to impart enantiospecificity to the surface. It has been shown, for instance, that tartaric acid adsorbed onto both Cu(110) and Ni(110) produces chiral surfaces. See, e.g., M. O. Lorenzo et al., Nature 404 376 (2000) and V. Humblot et al., J. Amer. Chem. Soc., 124, 503 (2002). A. Kuhnle et al., Nature, 415, 891 (2002) reported that cysteine adsorbed on Au(110) from a racemic mixture forms molecular pairs which are exclusively homochiral. Y. Izumi et al., Adv. Catal., 32, 215 (1983) reported that Raney Ni modified with (R,R)-tartaric acid can be used to catalyze the hydrogenation of β-ketoesters, producing the R-product with over 90% enantiomeric excess. Switching the enantiomer of the adsorbate switches the product to the S-isomer. One problem with this approach to heterogeneous catalysis is that the adsorption of chiral modifiers needs to be carefully maintained during the synthesis. See, C. LeBlond et al., J. Amer. Chem. Soc., 121, 4920 (1999).
[0005] Another approach to the preparation of chiral heterogeneous catalysts is to use high-index surfaces of single crystals. These high-index surfaces are prepared by slicing a low-index single crystal at an angle. The groups of Gellman and Attard have shown that high-index faces of fcc metals can exhibit chirality due to kink sites on the surface. For example, Pt and Au metal crystals with (643) and ({overscore (64)}{overscore (3)}) faces are enantiomorphs. See, e.g., C. F. McFadden et al., Langmuir, 12, 2483 (1996); J. D. Horvath et al., J. Amer. Chem. Soc., 123, 7953 (2001); op. cit., 124, 2384 (2002); A. Ahmadi et al., Langmuir, 15, 2420 (1999); G. A. Attard et al., J. Phys. Chem. B. 103, 1381 (1991); op. cit., 105, 3158 (2001). D. S. Sholl et al., J. Phys. Chem. B. 105, 4771 (2001) have proposed a naming and characterization scheme for these chiral metal surfaces. Only the surface of these materials is chiral, because the fcc metals are highly symmetrical and do not have chiral space groups. The (531) surface of Pt has been shown to be enantioselective for the electrochemical oxidation of 1-glucose by A. Ahmadi et al., Langmuir, 15, 2420 (1959). However, there are presently no heterogeneous catalysts that can be used for chiral synthesis on a commercial scale.
[0006] Thus, there is a continuing need for enantiospecific heterogeneous catalysts, that are sufficiently stable so that they can be easily separated from the starting materials and products. There is also a need for chiral surfaces that can be used as electrochemical sensors to detect chiral molecules.
SUMMARY OF THE INVENTION
[0007] A composition of matter is provided comprising a solid substrate or body having a surface which is chiral (i.e., having handedness). This chiral surface is produced on an achiral substrate surface, preferably by electrodeposition of metal oxide films on the surfaces. The handedness of the resultant surfaces is determined by the chirality of film precursors such as organometallic salts, such as complexes, in the electrodeposition solution.
[0008] The chiral surfaces can be used as heterogeneous catalysts for the enantiospecific syntheses of chiral molecules. They can also be used to produce enantiospecific chemical and biological sensors. One application of the invention is envisioned to be the production and analysis of single enantiomer drugs in the pharmaceutical industry. There are presently believed to be no commercially useful heterogeneous catalysts for chiral synthesis. The method of the invention can also be used to produce sensors for chiral molecules such as chemical warfare agents. The present synthetic method is simple and inexpensive, and is widely applicable.
[0009] In one embodiment of the invention, chiral CuO is grown on achiral Au(001) by epitaxial electrodeposition. The handedness of the film is determined by the specific enantiomer of tartrate ion in the deposition solution. (R,R)-tartrate produces an S—CuO(1 {overscore (1)} {overscore (1)}) film, while (S,S)-tartrate produces an R-CuO({overscore (1)} 1 1) film. These chiral CuO films are enantiospecific for the electrochemical oxidation of (R,R) and (S,S)-tartrate.
[0010] Therefore, an electrode comprising such a chiral surface can be used to electrochemically oxidize an organic molecule comprising at least one chiral center by oxidizing the organic molecule and an enantiomer thereof with said electrode having a surface of the same chirality as said chiral center under conditions so as to selectively oxidize said organic molecule. The oxidized molecule may be an intermediate or end-product in a synthetic route to a bioactive compound that can then be readily separated from the unoxidized enantiomer(s) thereby accomplishing the resolution or partial resolution of the end-product.
BRIEF DESCRIPTION OF THE FIGURES
[0011] FIG. 1 depicts the Bragg-Brentano (θ-2θ) x-ray diffraction scan probing the out-of-plane orientation of CuO that was electrodeposited from a solution of Cu(II)(S,S-tartrate) onto a single-crystal Au(001) surface. Only the (1 {overscore (1)} {overscore (1)}) and (2{overscore (22)}) peaks of CuO are observed, indicating that the system has the CuO(1 {overscore (1)} {overscore (1)})//Au(001) epitaxial relationship. The x-ray radiation is CuKα 1 , with a wavelength of 0.1540562 nm.
[0012] FIG. 2 depicts the x-ray pole figures of CuO films on Au(001) deposited from (A) Cu(II)(R,R-tartrate) and (B) Cu(II)(S,S-tartrate) and (C) racemic Cu(II) tartrate. The film grown in Cu(II)(R,R-tartrate) has a [1 {overscore (1)} {overscore (1)}] orientation, and the film grown in Cu(II)(S,S-tartrate) has a [{overscore (1)} 1 1] orientation. The two films are enantiomorphs. The film in (A) has an S configuration, and the film in (B) has an R configuration. The film in (C) deposited from the racemic mixture shows equal amounts of R and S configurations. The radial grid lines on the pole figures correspond to 30° increments of the tilt angle.
[0013] FIG. 3 outlines the chiral electrodeposition scheme and the resulting surfaces. Chiral CuO is electrodeposited onto achiral Au(001). The dark red spheres at the bottom of the figure represent Cu atoms. There are two non equivalent O atoms which are colored blue. The solid, blue colored O atoms are closest to the Cu plane, and sit in three-fold hollow sites. The hollow, blue O atoms are nearly atop the Cu atoms. The two orientations of CuO are clearly nonsuperimposable mirror images.
[0014] FIG. 4 depicts linear sweep voltammograms comparing the electrocatalytic activity of (A) an S—CuO film grown in Cu(II)(R,R-tartrate) with that of (B) an R-CuO film grown in Cu(II)(S,S-tartrate) for the oxidation of tartrate. The S—CuO(1 {overscore (1)} {overscore (1)}) film is enantioselective for the oxidation of (R,R)-tartrate, and the R-CuO({overscore (1)} 1 1) film is enantioselective for the oxidation of (S,S)-tartrate. A control film deposited from racemic Cu(II)(tartrate) shown on (C) has no enantioselectivity. The voltammograms were run at room temperature at a sweep rate of 10 mV/s in a stirred solution of 5 mM (R,R) and (S,S)-tartrate in 0.1 M NaOH.
[0015] FIG. 5 depicts a linear sweep voltammograms comparing the electrocatalytic activity of a CuO film grown in S,S-, R,R- and racemic copper tartrate solutions on oxidation of tartrate on a polycrystalline Au substrate.
[0016] FIG. 6 depicts Bragg-Brentano scans of CuO films on Cu(111) single crystals. The film in (A) was electrodeposited from a solution of Cu(II) (R,R)-tartrate while the film in (B) was deposited from a solution of Cu(II) (S,S)-tartrate.
[0017] FIG. 7 depicts CuO(111) pole figures of a film electrodeposited from solutions of Cu(II) (R,R)-tartrate (A) and Cu(II) (S,S)-tartrate (B). The (111) and (200) CuO planes have similar d-spacings and are both observed in the pole figure.
[0018] FIG. 8 depicts cyclic voltammograms obtained at a scan rate of 10 mV/s from 5 mM solutions of (S,S)- and (R,R)-tartrate in 0.1 m NaOH on (A) a CuO(1 {overscore (1)} {overscore (1)}) working electrode and (B) a CuO({overscore (1)} 1 1) working electrode. The CuO(1 {overscore (1)} {overscore (1)}) surface is seen to be more active toward the oxidation of (R,R)-tartrate while the CuO({overscore (1)} 1 1) surface is seen to be more active toward the oxidation of (S,S)-tartrate. The inset in (A) shows the arrangement of Cu atoms on the (1 {overscore (1)} {overscore (1)}) plane and the counter-clockwise rotation observed when assigning priority to increasing distances between the Cu atoms. The inset in (B) shows the same, except on the ({overscore (1)} 1 1) surface. In this instance a clockwise rotation is obtained.
DETAILED DESCRIPTION OF THE INVENTION
[0019] The present invention provides stable surfaces that can finction as enantiospecific heterogeneous catalysts and sensors. These surfaces are formed by the electrodeposition of epitaxial films of low symmetry materials, such as monoclinic CuO, from solution onto high symmetry achiral surfaces such as cubic Au(001) or single crystal Cu(111). As used herein, the term “achiral surface” or “achiral array” includes both ordered achiral surfaces, such as single crystal, textured or polycrystalline surfaces, as well as the surfaces of chiral materials that do not have a center symmetry. In other words, it is not necessary that the metal oxide crystallize in a chiral space group, so long as the surface does not contain a center of symmetry. The chirality of solution precursors such as organic counterions, e.g., salts such as metal amino acid salts or metal salts of chiral chelators, controls the handedness of the electrodeposited film. Useful chelators are disclosed, e.g., in U.S. Pat. Nos. 5,300,279, 4,853,209 and 4,882,142.
[0020] Electrodeposition has been used to deposit epitaxial films of metal oxides such as CuO, Cu 2 O, AgO, ZnO, Pb—Tl—O, and iron oxides such as Fe 3 O 4 on various metals, such as gold, platinum, copper which may be single crystal, textured or polycrystalline, and on ceramic and semiconductor surfaces, such as single crystal silicon. Polycrystalline materials include sputtered or evaporated films of metals such as gold or platinum, on substrates such as foils or plastics. See, e.g., results reported by the J. A. Switzer group in Science, 284, 293 (1999); Chem. Mater., 11, 2289 (1999); Chem. Mater., 13, 508 (2001); Chem. Mater., 14, 2750 (2002); J. Amer. Chem. Soc., 124, 7604 (2002); J. Phys. Chem. B, 106, 12369 (2002). The deposition solution and applied potential can have a profound effect on the crystallographic orientation and morphology of the epitaxial films. For example, films of electrodeposited Cu 2 O have a crystallographic orientation that is pH dependent. A film of Cu 2 O deposited on Au(001) at pH 12 undergoes a transition from a thermodynamically-controlled orientation to a kinetically-controlled orientation after reaching a critical thickness. See, J. A. Switzer et al., J. Phys. Chem. B, 106, 4027 (2002). Other useful metal oxides can include Co 3 O 4 , MnO 2 and Mn 3 O 4 .
Example 1
[heading-0021] Deposition of CuO Films on Au(001)
[0022] The CuO films in this study were deposited using the general method of P. Poizot et al., Electrochemical and Solid State Letters, 6, C21-C25 (2003). The CuO films were deposited to a thickness of about 300 nm at 30° C. onto a polished and H 2 -flame-annealed Au(001) single crystal at an anodic current density of 1 mA/cm 2 from an aqueous solution of 0.2 M Cu(II), 0.2 M tartrate ion, and 3 M NaOH. The electrodeposited CuO has a monoclinic structure (space group=C2/c) with a=0.4685 nm, b=0.3430 nm, c=0.5139 nm, and β=99.080.
[0023] X-ray diffraction measurements were done on a high-resolution Philips X'Pert MRD diffractometer. For the Bragg-Brentano scan the primary optics module was a combination Gobel mirror and a 2-crystal Ge(220) 2-bounce hybrid monochromator, and the secondary optics module was a 0.18° parallel plate collimator. The hybrid monochromator produces pure CuKα 1 radiation (λ=0.1540562 nm) with a divergence of 25 arcseconds. Pole figures were obtained in point-focus mode using a crossed-slit collimator as the primary optics and a flat graphite monochromator as the secondary optics. A 2θ value of 38.742° was used to probe the (111) reflection of CuO. Enantiomeric excesses were determined from CuO(111) azimuthal scans at 2θ=38.742° and χ=63° by integrating the area under the (111) and ({overscore (1)} {overscore (1)} {overscore (1)}) peaks due to the R and S forms of CuO, respectively.
[0024] A Bragg-Brentano X-ray diffraction pattern is shown in FIG. 1 for an epitaxial film of CuO on Au(001) that was electrodeposited from a solution of Cu(II)(R,R)-tartrate. The film has a strong [1 {overscore (1)} {overscore (1)}] orientation, indicating that the system has a CuO(1 {overscore (1)} {overscore (1)})//Au(001) epitaxial relationship. This is similar to the result obtained by other workers for the vapor deposition of CuO on MgO. In that case the film grew with a [111] orientation on MgO(001). See A. Catana et al., Phys. Rev. B, 46, 15477 (1992) and I. M. Watson et al., Thin Solid Films, 251, 51 (1994). The orientation of electrodeposited CuO can be changed to [1 {overscore (1)} 1] by depositing the film from a solution of Cu(II)(S,S)-tartrate. The [1 {overscore (1)} {overscore (1)}] and [{overscore (1)} 1 1] orientations are not distinguishable by Bragg-Brentano scans, because the d-spacings for the two orientations are identical.
Example 2
[heading-0025] Determination of Absolute Conflguration of Deposited Films
[0026] The absolute configuration of the electrodeposited films was determined by X-ray pole figure analysis. Pole figures can be used to probe planes which are not parallel with the geometric surface of the sample. The sample is moved through a series of tilt angles, χ, and at each tilt angle the sample is rotated through azimuthal angles, Φ, of 0 to 360°. Peaks occur in the pole figure when the Bragg condition is satisfied. Pole figures are shown in FIG. 2 a and 2 b for CuO films that were deposited from (R,R) and (S,S)-tartrate solutions, respectively. The (111) planes of CuO were probed because they are close in d-spacing to those of Au(111). Therefore, there are four peaks at χ=55° which result from the Au. These serve as an internal reference point for the CuO peaks. Overlapping with the four Au peaks are peaks due to CuO(1 {overscore (1)} 1) in FIG. 2 a and CuO({overscore (1)} 1 {overscore (1)}) in FIG. 2 b . There are also four peaks at χ=63° which correspond to CuO({overscore (1)} {overscore (1)} {overscore (1)}) in FIG. 2 a and CuO(111) in FIG. 2 b . By comparison with stereographic projections for the monoclinic structure, these can be assigned as a [1 {overscore (1)} {overscore (1)}] orientation for the film grown in (R,R)-tartrate ( FIG. 2 a ), and a [{overscore (1)} 1 1] orientation for the film grown in (S,S)-tartrate ( FIG. 2 b ). In each case there are four equivalent in-plane orientations, with the [110] direction of CuO coincident with the [110], [1 {overscore (1)} 0], [{overscore (1)} 1 0], and [{overscore (1)} {overscore (1)} 0] directions of Au. The two pole figures in FIGS. 2 a and 2 b are nonsuperimposable mirror images, indicating that the two films are enantiomers.
[0027] The chiral deposition scheme is outlined in FIG. 3 . The surfaces shown are ideal terminations of the bulk structure. In this figure, the smaller Cu atoms are dark red, and there are two distinct oxygen atoms. The solid blue-colored oxygen atoms are closest to the Cu plane, and sit in three-fold hollow sites. The hollow, blue-colored oxygen atoms are situated nearly atop the Cu atoms. The [1 {overscore (1)} {overscore (1)}] and [{overscore (1)} 1 1] orientations of CuO shown in the figure are nonsuperimposable mirror images. Although CuO has an achiral space group, the [1 {overscore (1)} {overscore (1)}] and [{overscore (1)} 1 1] faces are enantromorphs because they lack a center of symmetry.
[0028] The handedness of the CuO films is determined by the chirality of the deposition solution, because the Au(001) surface has high symmetry and does not impart the chirality. This chiral electrodeposition can be attributed to the adsorption of either free tartrate ions or Cu(II)(tartrate) complexes on the Au surface. The modified surface induces chiral electrodeposition of the CuO epitaxial films. Complexes of Cu(II)(tartrate) have a dimeric structure with a symmetry that is determined by the handedness of the tartrate ligands (R. J. Missavage et al, J. Coord. Chem., 2, 145 (1975)). M. O. Lorenzo et al., Nature, 404, 376 (2000) have shown that tartrate can adsorb onto Cu(110) to form chiral surfaces.
[0029] Using the method of G. A. Attard et al., J. Phys. Chem. B. 103, 1381 (1999), an R or S designation can be assigned to the two enantiomorphs. By analogy to the Cahn-Ingold-Prelog sequence rules for organic molecules, an arbitrary “priority” is assigned to each of the low index planes of a crystal based on the surface packing density. For fcc metals this sequence is {111}>{100}>{110}. If the {111}→{100}→{110} sequence runs clockwise in the stereographic projection of the material along a particular zone axis, the orientation is designated “R.” Counter clockwise rotation yields the designation “S.” Although this notation is arbitrary, it does allow one to assign a label to each of the enantiomers; the R-enantiomer of CuO deposits with an 85% enantiomeric excess from the (S,S) tartrate solution, and the S-enantiomer deposits with a 90% enantiomeric excess from the (R,R)-tartrate solution.
Example 3
[heading-0030] Electrochemical Oxidation Of Tartrate
[0031] The pole figures show that the films grown in (S,S) and (R,R)-tartrate are enantiomers, but they do not provide information on the chirality of the surface. In order to probe the surface chirality, the electrochemical activity for films deposited in the two solutions was compared for the electrochemical oxidation of (R,R) and (S,S)-tartrate. CuO has been shown by other workers to be a potent electrocatalyst for the oxidation of carbohydrates, amino acids, simple alcohols, aliphatic diols, and alkyl polyethoxy alcohol detergents. See, e.g., K. Kano et al., J. Electroanal. Chem., 372, (1994) and Y. Xie et al., Anal. Chem., 63, 1714 (1991). Chiral recognition by CuO has not been demonstrated previously. Linear sweep voltammograms are shown in FIG. 4 for the oxidation of (R,R) and (S,S)-tartrate on CuO electrodes which were deposited from Cu(II)(R,R)-tartrate ( FIG. 4 a ) and Cu(II)(S,S)-tartrate ( FIG. 4 b ). The linear sweep voltammograms in FIG. 4 were run at room temperature in stirred solutions of 5 mM (R,R) and (S,S)-tartrate in 0.1 M NaOH at a sweep rate of 10 mV/s. The S—CuO film grown in (R,R)-tartrate is more active for the oxidation of the (R,R)-tartrate, and the R-CuO film grown in (S,S)-tartrate is more active for the oxidation of the (S,S)-tartrate. A control film shown in FIG. 4 c that was deposited from a racemic mixture of the (R,R)- and (S,S)-tartrates shows no selectivity for the oxidation of the enantiomers.
Example 4
[heading-0032] Enantiomorphic CuO Films Grown On Polycrystalline Gold
[0033] Following the procedures of Example 1, CuO films were grown on polycrystalline gold using both Cu(II) tartrate enantiomers and a racemic mixture.
[0034] Linear sweep voltammograms comparing the electrocatalytic activity of a CuO film grown in (a) Cu(II)(R,R-tartrate), (b) Cu(II)(S,S-tartrate), and (c) Cu(II)(racemic-tartrate) for the oxidation of tartrate on a polycrystalline Au substrate are depicted in FIG. 5 . The CuO films grown in Cu(II)(R,R-tartrate) and Cu(II)(S,S-tartrate) are enantioselective for the oxidation of (R,R)-tartrate and (S,S)-tartrate, respectively. A control film deposited from racemic Cu(II)(tartrate) shown in (c) has no enantiospecificity. The voltammograms were run at room temperature at a sweep rate of 10 mV/s in an unstirred solution of uncomplexed 5 mM (R,R) and (S,S)-tartrate in 0.1 M NaOH. The area of the polycrystalline gold electrode was 0.13 cm 2 . The (R,R)-tartrate and (S,S)-tartrate voltammograms are designated with solid and dashed lines, respectively.
Example 5
[heading-0035] Enantiospecific Electrodeposition of Chiral CuO Films on Single-Crystal Cu(111)
[0036] Two CuO films were electrodeposited at 0.4 V vs. SCE for 45 minutes on a Cu(111) single crystal from a solution of 0.2 M Cu(II), 0.2 M tartrate ion in 3M NaOH at 30° C. The anodic charge density was 8 C/cm 2 , and the films were 400 nm thick. FIG. 6A shows the Bragg-Brentano x-ray diffraction pattern for the film deposited from Cu(II) (R,R)-tartrate and FIG. 6B shows the pattern for the film deposited from Cu(II) (S,S)-tartrate. From the Bragg-Brentano patterns it appears that there is no difference between the two highly textured films. However, analysis of pole figures obtained from the epitaxial films demonstrates that the films actually have two different orientations, CuO(1 {overscore (1)} {overscore (1)}) in FIG. 6A and CuO({overscore (1)} 1 1) in FIG. 6B .
[0037] Epitaxial electrodeposition has been demonstrated for a number of oxides on single crystal metal and semiconductor substrates. See, e.g., Th. Pauporte et al., Appl. Phys. Lett, 75, 3817 (1999); Th. Pauporte et al., Chem. Mater., 14, 4702 (2002); J. A. Switzer et al., J. Phys. Chem. B., 106, 12369 (2002). Because the CuO in the present work was deposited onto single-crystal Cu(111) the absolute configuration of the film can be determined by x-ray pole figure analysis. By choosing a specific d-spacing to probe while measuring diffracted intensity as a function of tilt and rotation, a pole figure is obtained. FIG. 7A shows the CuO (111) pole figure for the CuO film deposited from Cu(II) (R,R)-tartrate while FIG. 7B shows the same pole figure for the CuO film deposited from Cu(II) (S,S)-tartrate. The two pole figures are clearly non-superimposible mirror images of one another. Further analysis reveals that each pole figure is a result of three crystalline domains rotated 120 degrees from one another. Although the d-spacing for the CuO(111) planes was probed for the pole figures in FIG. 7 , diffraction from the CuO(200) planes is also observed as the two d-spacings are not sufficiently resolved from one another. The film examined in FIG. 7A is consistent only with a CuO(1 {overscore (1)} {overscore (1)}) out of plane orientation while the film in FIG. 7B has a CuO({overscore (1)} 1 1) out of plane orientation. Although not shown due to space limitations, CuO films deposited from Cu(II) complexed with racemic tartrate show equal amounts of the CuO(1 {overscore (1)} {overscore (1)}) and CuO({overscore (1)} 1 1) orientations.
[0038] FIG. 8A shows cyclic voltammograms obtained on a CuO(1 {overscore (1)} {overscore (1)}) film in 5 mM solutions of (S,S)- and (R,R)-tartrate in 0.1 M NaOH, while FIG. 8B shows the same for a CuO({overscore (1)} 1 1) film on Cu(1 1 1). The electrodeposited CuO acts as a catalyst toward the oxidation of tartrate as well as exhibiting enantioselectivity toward the different chiral forms of the ion. Examination of FIG. 8A reveals that the CuO(1 {overscore (1)} {overscore (1)}) film more readily oxidizes (R,R)-tartrate while the CuO({overscore (1)} 1 1) film more readily oxidizes the (S,S)-tartrate as seen in FIG. 8B . Although not shown due to space considerations, CuO films deposited from the racemic Cu(II) tartrate show identical voltammograms in the (R,R)- and (S,S)-tartrate solutions.
[0039] The enantioselective adsorption of tartrate or that of the Cu(II) tartrate complex itself on single-crystal Cu is almost certainly related to the enantioselective electrodeposition observed here. Although the exact mechanism of enantioselectivity observed with cyclic voltammetry is under investigation, one can see how it may arise by examining the arrangement of Cu atoms on the (1 {overscore (1)} {overscore (1)}) and ({overscore (1)} 1 1) CuO planes. The Cu atoms on the CuO(1 {overscore (1)} {overscore (1)}) plane have a pseudo-hexagonal arrangement with three slightly different spacings between the copper atoms. If a rotation is arbitrarily assigned based on increasing spacing between the Cu atoms we obtain a counter-clockwise rotation as seen in the inset in FIG. 8A . Applying the same set of rules a clockwise rotation is obtained for the Cu atoms on the CuO ({overscore (1)} 1 1) plane as seen on the inset in FIG. 8B . The arrangement of Cu atoms on the two planes lack a center of symmetry and they are nonsuperimposible mirror images of one another. The tartrate ions may not necessarily be interacting with Cu atoms on the ({overscore (1)} 1 1) and (1 {overscore (1)} {overscore (1)}) planes, but one can reasonably assume that the “true” surface of interaction would contain some manifestation of this two-dimensional chirality.
[0040] The present invention thus is exemplified by a method for the electrodeposition of chiral films of CuO onto achiral Au(001) or single crystal Cu(111) surfaces using chiral molecules to direct the enantiospecific deposition. The present examples use a single crystal substrate, so that the absolute configuration can be obtained by X-ray diffraction. For practical applications, inexpensive polycrystalline or textured substrates will be employed, such as rolling-assisted biaxially textured substrates (RABiTS®). These single-crystal-like tapes are available at a relatively low cost for a variety of metals, including copper, and can be used as a cost-effective substrate for enantiospecific electrodeposition. See, e.g., D.P. Norton et al., Science, 274, 755 (1996).
[0041] The present chiral electrodeposition method can be generally used for the deposition of other chiral catalysts, and for the synthesis and sensing of other chiral molecules. Post-chromatographic chiral electrochemical sensors can obviate the need for chiral separations prior to chemical detection.
[0042] Electrodeposition also affords the ability to control the morphology and orientation of the films by varying solution conditions, which can be useful in designing these chiral surfaces. See, J.A. Switzer et al., J. Phys. Chem. B., 106 4027 (2002).
[0043] All publications, patents and patent applications referred to herein are incorporated herein by reference. While in the foregoing specification this invention has been described in relation to certain preferred embodiments thereof, and many details have been set forth for purposes of illustration, it will be apparent to those skilled in the art that the invention is susceptible to additional embodiments and that certain of the details described herein may be varied considerably without departing from the basic principles of the invention. | A solid substrate comprising a surface comprising an achiral array of atoms having thereupon a chiral metal oxide surface. | 2 |
TECHNICAL FIELD
This invention pertains to the processing of certain metal alloys to produce an orange peel-like textured surface. More specifically, this invention pertains to the controlled cold working of a superplastic-formable (SPF) metal alloy sheet so as to yield a roughened textured surface in at least a portion of the sheet upon stretch forming at a suitable elevated temperature and strain rate.
BACKGROUND OF THE INVENTION
There are families of metal alloy compositions that when subjected to suitable thermomechanical processing display extraordinary elongation or plastic deformation properties. They are then said to have superplastic forming properties (or to be superplastically formable, either phrase sometimes abbreviated as SPF). Some aluminum, iron, magnesium and titanium compositions have such properties. Often SPF materials have a metallurgical microstructure characterized by a matrix phase of the major constituent such as aluminum, or of a solid solution of the major phase and minor alloying elements, and very finely divided dispersed phase of intermetallic material. Materials with such a microstructure are sometimes called pseudo-single phase materials because of the very small dispersed phase. In sheet form, such materials can be cold rolled to reduce thickness and increase length while breaking up the existing grains and storing the work energy in the microstructure of the sheet. Then, upon heating to a suitable temperature, the strain is relieved by recrystallization to yield a very fine grain microstructure susceptible to forming operations at a suitable temperature to produce complex shapes from the sheet in which portions have experienced extraordinary elongation and deformation.
Certain SPF titanium alloy sheet compositions (e.g., Ti-6% Al-4% V alloys) have probably been the first materials to be used commercially. They have been used in the aerospace industry because of their very favorable strength-to-weight ratio. These sheet materials are formed at suitable elevated temperatures in the range of, for example, 800° C. to 900° C. into complicated one-piece shapes that often eliminate the previous need to form several smaller pieces and join them together. The sheets experience strain rates of 10 −4 to 10 −3 and elongation of several hundred percent. The need of the aerospace industry for strong lightweight parts has permitted the use of expensive alloys and relatively slow manufacturing processes. At present, however, SPF practices with titanium alloys have been too expensive for the lower cost requirements of the automobile industry.
Work has begun to adapt some aluminum alloys to lower-cost SPF processes and part manufacture. For example, AA 5083 has been formed by hot rolling of a cast ingot to a strip and subsequent severe cold rolling of the strip to a sheet material that is a precursor for SPF part manufacture. AA5083 have typical compositions, in weight, of about 4% to 5% magnesium, 0.4% to 1% manganese, 0.05% to 0.25% chromium, about 0.1% copper, and the balance aluminum. The cold-rolled sheets are heated to a suitable temperature of, e.g., about 500° C. where recrystallization to a fine grain (about 10 m) microstructure quickly occurs and the sheet is warm enough to be formed with relatively high elongation for such alloys. The heated sheet is placed adjacent a suitable forming tool, secured at the edges and stretched against and into compliance with the forming tool using the pressure of a gas such as air, nitrogen or argon.
SPF practices for the stretch forming of aluminum alloys such as AA5083 are illustrated in patents such as U.S. Pat. No. 5,819,572 Krajewski, “Lubrication System for Hot Forming;” U.S. Pat. No. 5,974,847 Saunders et al, “Superplastic Forming Process;” and U.S. Pat. No. 6,047,583 Schroth, “Seal Bead for Superplastic Forming of Aluminum Sheet,” each assigned to the assignee of this invention. As suggested in these patents, the goal in developing SPF practices for the manufacture of aluminum sheet products on a commercial scale has been to make tear-free articles with unmarred surfaces. But it would also be useful to form sheet metal products with SPF-like capabilities that have textured, or uniformly roughened surfaces, in at least a portion of the article. In other words, there are applications for SPF-type formed parts that have an orange peel-like surface of decorative or anti-skid properties or the like.
SUMMARY OF THE INVENTION
This invention provides a method of forming a SPF-type metal alloy sheet of specified thickness so that at least a portion of the resulting product has a surface with a visible uniform rough texture like the skin of an orange. The invention is applicable to metal alloys that can be cold worked to a sheet stock precursor having a suitable strained microstructure that will recrystallize to a fine-grained microstructure with high elongation characteristics upon heating to a recrystallization (and forming) temperature. The practice of the invention involves predetermining the amount of cold work that is to be applied to the precursor sheet stock so that, upon heating to a superplastic-forming temperature for the material and subsequent stretch forming, the deformation of the sheet results in a desired shape and the textured surface. For applications such as the manufacture of automobile body panels, SPF aluminum alloys are preferred because of their combination of low weight, high strength and low cost.
The preparation of a superplastic-formable, aluminum alloy sheet stock usually begins with a casting of a suitable composition such as AA5083. The cast material is then reduced in thickness by hot rolling to a strip that may, for example, have a thickness in the range of 20 to 40 millimeters depending somewhat on the goal for the final thickness of the sheet. The hot rolled strip is then cold rolled, usually in stages with possible interposed anneals, to a final thickness in the range of about one to three or four millimeters. The result of overall thermomechanical processing is typically a coil of smooth surface aluminum sheet stock, the microstructure of which has been severely strained. This material is then ready to be heated to 500° C. or so for stretch forming as described above. The effect of the heating is to promote recrystallization of the severely worked microstructure to a very fine grained material susceptible to appreciable elongation during deformation by stretching against the forming tool.
In conventional superplastic forming of aluminum sheet, the goal is to obtain a sheet stock of desired thickness that ends up with a suitably fine grained microstructure to sustain deformation and elongation at the various critical spots on the sheet to form the desired part with at least one smooth surface and without body tears, ruptures, undue thinning and the like. In order to assure suitable elongation for any SPF job, the current sheet stock rolling practice is to maximize the cold rolling strain imposed on the sheet stock consistent with the specified thickness of the sheet stock. Depending upon the shape of the part to be formed, the sheet stock may then have sufficient or excess elongation (i.e., formability) for the task.
In accordance with this invention, a sheet product is formed from a stock material having marginally less formability than SPF starting material. The shape of the product will not require the extensive deformation obtained in an SPF process, but the product, upon heating to a suitable elevated temperature and stretch forming, will have a generally uniformly roughened surface portion. The amount of cold rolling strain imposed on the sheet is carefully determined to be less than that required for optimum SPF deformation but sufficient to make the part and to yield the textured surface. In other words, the creation of the textured surface is the result of a cold working and thermal recrystallization strategy that produces a defective part as far as SPF processing is concerned, i.e., a part with a roughened surface. Manufactured sheet metal parts with rough surfaces have utility for decorative purposes, low slip applications, coating adhesion, controlled heat transfer and the like.
Other objects and advantages of the invention will become more apparent from a detailed description of preferred embodiments which follows.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a graph illustrating recrystallized grain size as a function of percentage reduction of a sheet by cold work.
FIG. 2 is a draftsman's sketch of a portion of an AA5083 sheet formed with a license plate pocket such as might be formed in an automobile decklid panel. But the formed sheet has also been formed with a textured surface as produced by a practice of this invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
It is believed that the invention can be well illustrated by comparison with conventional SPF technology as applied to the stretch forming of AA5083 material.
Currently, AA5083 material is supplied for some SPF manufacturing operations in the H18 temper designation condition. The H18 designation means that the material was cold rolled at a temperature not exceeding about 50° C. for significant periods of time to a reduction of 74% or more as the last processing step, thereby producing a very “hard” material. The coil does heat up during cold rolling and, therefore, the rolling is often carried out in multiple steps so that the coil can cool, sometimes overnight, between steps. In other words, originally cast material is hot rolled to a desired intermediate thickness, fully annealed and then cold rolled without intermediate anneal to about one-quarter of its annealed thickness. The final thickness of the cold-worked sheet is typically in the range of one to two millimeters.
When the H18 AA 5083 blank is heated to a suitable SPF-forming temperature, e.g. 500° C., the energy stored in the sheet microstructure by the cold-working process is released through the recrystallization of new grains or crystals in the material. The higher the amount of cold work prior to heating, the more nuclei/unit volume form, which then leads to a finer and more uniform grain size. This is advantageous for the SPF process as finer grains produce better formability which allows products with more complex geometries to be formed in less time. In addition, the fine, uniform grain structure produced by this process also leads to smooth surface finishes in as-formed components. Thus, for the above reasons, SPF material has been typically produced with the finest grain size possible.
While a fine grain size is desired for optimum formability of complex panel shapes, some components can be manufactured with less than optimum material. For example, one panel shape may require a material to exhibit a minimum of about 300% elongation under stretch forming conditions of 500° C. and at a strain rate of 0.001/sec while a different panel can be successfully made using material which exhibits significantly less elongation under these conditions. Another body closure inner panel shape requires AA5083 material with an elongation of nearly 400% to make a reasonable cycle time. Thus, it is clear that a significant difference exists in the quality (meaning the elongation or deformability) of material required for different body panel SPF-forming applications. When the sheet stock is processed to have suitable formability to make a specified part shape the part can be stretch formed at 500° C. or so quickly without incurring tears or ruptures in the part and without surface defects resulting from uneven deformation of the microstructure. However, there may be some parts in which a surface texture is wanted. In order to produce such parts, one must rethink the strategy that leads to successful SPF part making.
In the case of automobile parts, for example, one might want aluminum truck running boards with textured low-slip surfaces, underbody panels with rough surfaces for coating retention, heat shields or floor pans with enhanced thermal radiation surfaces, or interior trim surfaces with decorative textured surfaces.
Applications requiring a “textured surface” require a method for using formable sheet material which exhibits less than optimum SPF utility but exhibits a post-formed surface that could create styling or marketing advantages otherwise unattainable. Satisfaction of this requirement involves a new way of using the known phenomena of critical strain recrystallization to produce SPF-type material with larger grains than those typically needed and used in the SPF process. The details of critical strain recrystallization are re-examined.
The grain size of a metal sheet can be controlled by the application of cold work or strain followed by a recrystallization heat treatment. The relationship between cold work (% CW or percentage reduction in thickness of the sheet) and grain size for an alloy like AA5083, for example, is shown generically and schematically in FIG. 1 where the X axis represents the amount of % CW added to O temper (dead soft) material and the Y axis represents the grain size produced by recrystallizing the material after the CW addition.
For small amounts of cold work (<3%), no change in grain size occurs after heat treating because no nuclei for recrystallization are formed. At some critical cold work level (typically between 3% and 5% for AA5083), a few nuclei are formed during heat treatment which produces a very large recrystallized grain size. As the amount of cold work or strain is increased, the amount of stored energy increases and thus the number nuclei also increases. As a result, the recrystallized grain size is smaller. Typically, SPF materials are produced by processing to the far right of curve in FIG. 1 where the high amount of cold work produces a large number of nuclei and thus a finer grain size, e.g., less than about 10 micrometers. The idea in the present method thus involves producing material by processing in the middle range of cold work where large grains can be produced. The cold work which is represented in FIG. 1 is cumulative as long as the material is not heat treated in between separate rolling events. Thus, sheet material given 3% cold work in one pass and 10% cold work in another pass would provide a grain size corresponding to 13% cold work in FIG. 1 after a recrystallization heat treatment.
This phenomena of grain size control in SPF materials can be achieved in current production practices using one of the following methods:
(1) The AA5083 material supplier produces standard H18 temper material slightly over the required thickness. The entire coil would then be passed through a continuous annealing line, or the entire coil could be flash annealed. This would convert the coil to O temper, essentially dead soft material. The coil would then be cold rolled to a thickness reduction (in percent of the original thickness of the O temper sheet) corresponding to the resulting grain size desired (e.g., 10% reduction) as experimentally determined (as in FIG. 1) for the specific part to be formed. The material could then be recrystallized either at the aluminum mill or during heat-up in the SPF part-making process.
(2) A current production process could be varied by replacing the 74% cold work in the final process step with the critical amount of cold work (e.g., 10% after an intermediate anneal) required to produce the desired grain size. This method may have two potential disadvantages. First, the material is not necessarily in the O temper after warm rolling, thus the starting point of the material would be unknown and the resulting surface texture could vary. This could pose a problem when trying to hit a very specific cold work level. Secondly, the formability could be lower with this process as the orientation of the large recrystallized grains may not be as random as they would be with the extra recrystallization step in #1.
(3) Material could be supplied to the user in the O temper (H18 material which was flash annealed at the supplier). The critical amount of strain could be applied to the blank prior to forming either by bending, rolling or other mechanical means. This process would be difficult to control as the amount of cold work may not be uniform across the blank prior to placing in the SPF press, thus producing an irregular microstructure and therefore an irregular surface.
Experimental
A cold-rolled sheet stock of AA5083 material was used. The sheet stock was annealed to a soft condition (O temper designation). One AA5083-O material was pre-strained by cold rolling to a 5% reduction in the thickness of the and a second sheet of the same material pre-strained to 10% reduction. This work was done by a supplier on a rolling mill.
The respective sheet samples were stretch formed at 500° C. against a tool shaped to form the license plate pocket region and adjoining surface region of an automobile decklid. This pocket region is an example of a relatively difficult part to form because it is of box-like shape with a flat bottom portion and steep sides and ends. The dimensions of the pocket were 520 mm long by 180 mm wide by 52 mm deep. The sheet samples were respectively heated to 500° C., clamped at their periphery over the female tool and pressed into close conformance with the tool surface by gradually increasing air pressure to a maximum level of 90 psi. The parts were formed after about six minutes of pressure application. The formed sheet license plate pockets were removed and cooled.
A trimmed sheet is illustrated in FIG. 2 . The formed sheet 10 included a flat peripheral portion 12 surrounding a license plate pocket portion 14 . The license plate pocket portion included fairly steeply sloped segmented side walls 16 and a top 18 and a bottom wall, obscured in this view. The pocket 14 also included a flat bottom 20 .
The AA5083 sheet sample pre-strained to 10% successfully formed the license plate pocket member without tear or rupture but the 5% prestrained sheet did not. Both sheets exhibited a rough, orange peel appearance over the entire part 10 after forming as illustrated by artist's sketch of FIG. 2 . The 10% pre-strained sheet had a finer grain structure to begin with, and it formed the part better, but its surface was less rough. Thus, depending upon the textured desired on the surface of the final part, one might specify an initial pre-strain amount of, for example, 5+% to 15%. Obviously, a balance must be accepted between the complexity of the SPF part to be formed and the roughness characteristic of the formed surface.
The subject surface texture forming process can be adapted to alloys which exhibit critical strain recrystallization phenomena such as aluminum, magnesium, steel and titanium. Suitable pre-strain levels for the surface texture desired can be established. In the case of AA5083, typical pre-strain levels for the roughened surface are in the range of about 3% to about 15%. Some latitude in the annealing and forming temperature is permitted. For example, in the case of AA5083, lower forming temperatures like 350° C. increase surface roughness while reducing formability. Obviously, there is latitude in the timing and location of the pre-strain step and the recrystallization step.
While the invention has been described in terms of some embodiments, it is appreciated that other forms could readily be adapted by persons skilled in the art. Accordingly, the scope of the invention is limited only by the scope of the following claims. | Pre-straining and thermal recrystallization processes for maximizing formability in SPF sheet alloys of aluminum, magnesium, iron and titanium can be modified to form sheet products with roughened or textured surfaces for low-slip applications or coating adherence or decorative applications. By determination of suitable pre-strain levels and recrystallization/forming temperatures for s sheet metal stock, relatively large grained microstructures are formed in the sheet that yield useful surface texture during forming. | 2 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims priority from German Patent Application No. 10 2005 055 915.8 dated Nov. 22, 2005, the entire disclosure of which is incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] The invention relates to an apparatus at a flat card or roller card for grinding a clothing drawn onto a rotating roller. Some grinding devices have a carrying device with at least one grinding element and an advancing device serving to set the grinding element against the clothing, the apparatus comprising a biasing device serving for automatically continuing to push forward the grinding element in a contact-making direction during the grinding procedure, and the carrying device being attached to the flat card or roller card.
[0003] When textile fibres are processed, the fibres are oriented and cleaned with the aid of flat cards or roller cards. Those fibre-processing apparatuses comprise at least one roller having a wall in the shape of a circular cylinder and carrying a fibre-processing clothing on its outer wall surface. For fibre processing, the roller is set in rotary motion relative to its cylinder axis. The clothing arranged on the outer wall surface passes through the fibre material and orients it, optionally in co-operation with further processing elements such as, for example, card flats, clearer rollers and the like. Cleaning of the raw material is, furthermore, also achieved by the fibre processing. In order to increase resistance to wear and to improve the quality of the textile fibre material, a so-called all-steel saw-tooth clothing is usually used as the fibre-processing clothing. A clothing of such a kind comprises a saw-tooth wire running on a helical course around the roller having a wall in the shape of a circular cylinder, the saw-teeth of which wire pass through the fibre material. In operation of the above-described wires, considerable wear of the fibre-processing clothing takes place. In addition, contaminants can gather in the region of that clothing. The latter-described problem especially comes to the fore when processing synthetic fibres, in the course of which the fibres can melt and stick to the clothing. Therefore, in order to achieve the desired quality of fibre material, it is necessary for the fibre-processing clothing to undergo processing regularly in order, in the course of that processing, to re-grind the tips of the clothing and/or to remove contaminants from the clothing.
[0004] In the case of a known apparatus (EP 1 430 997 A), after mounting of the grinding arrangement on the machine frame of a flat card or roller card, the desired orientation of the grinding arrangement with respect to the clothing to undergo processing is first adjusted with the aid of an adjusting screw. By that means, the contact pressure (biasing device) of the grinding element against the clothing is adjusted. The processing arrangement is then lifted up off the clothing by actuating a pneumatic lifting cylinder, the roller together with the clothing is caused to rotate and the processing arrangement is advanced towards the clothing by again actuating the pneumatic lifting cylinder. It is disadvantageous that the grinding arrangement has to be adjusted in an additional preparatory step, for which the grinding element is firstly set against the non-rotating clothing. In addition, for adjustment of the biasing device, additional outlay in terms of apparatus is required. It is furthermore disadvantageous that, in the case of mobile use or replacement of the apparatus, the time-consuming adjustment procedure is additionally required.
[0005] It is an aim of the invention to provide an apparatus of the kind described at the beginning that avoids or mitigates the mentioned disadvantages and that especially is simple in terms of construction and installation and makes it possible to reduce substantially the preparation time for service-readiness.
SUMMARY OF THE INVENTION
[0006] The invention provides a grinding device for use at a carding machine for grinding a clothing on a rotating roller of the carding machine with which is associated a plurality of cover elements and/or work elements comprising:
a carrying device with at least one grinding element and an advancing device serving to set the grinding element against the clothing; and a biasing device for automatically continuing to push forward the grinding element in a contact-making direction during the grinding procedure; wherein the carrying device is attachable to the carding machine, and the grinding device with the grinding element is so constructed that it is interchangeable with a said cover element or a said work element.
[0009] As a result of the fact that the roller clothing is associated with the carrier having the at least one grinding element, instead of with a cover element or work element, the outlay in terms of apparatus and the time outlay required for service-readiness are substantially reduced. As a result of replacing a stationary cover element or work element by the carrier having the grinding element, arrangement and removal of the grinding device can be carried out in a short time by simple means. A particular advantage is provided by the fact that the dimensions over the length and width of the carrier and cover element or work element are the same or substantially the same. This allows replacement of the grinding device by a cover element or work element on the same flat card as well as mobile use on another flat card.
[0010] The invention further provides a carding machine including a grinding device for grinding a clothing on a rotating roller of the carding machine with which is associated a plurality of cover elements and/or work elements, the device comprising:
a carrying device with at least one grinding element and an advancing device serving to set the grinding element(s) against the clothing; and a biasing device for automatically continuing to push forward the grinding element(s) in a contact-making direction during the grinding procedure; wherein the grinding device is so mounted that the grinding element or elements can be brought into contact with the roller clothing and is so configured and dimensioned that it is interchangeable with a said cover element or work element.
[0013] Advantageously, carrying elements adjustable for adjustment of the cover elements and/or work elements relative to the roller are utilised for adjustment of the biasing device. Advantageously, on both sides of the roller there are provided side parts having carrying elements, the peripheral region of which has in the radial direction predetermined spacings relative to a reference point of the roller, and the carrying device of the grinding apparatus is associated with the carrying elements of the side parts. Advantageously, at least one grinding element is arranged to be displaced, during the grinding procedure, in the direction of a displacement path extending perpendicular to the contact-making device. Advantageously, the biasing device is arranged to be displaced in the direction of the displacement path together with the at least one grinding element. Advantageously, the at least one grinding element has an articulated connection to the biasing device by means of a joint. Advantageously, a universal joint is used. Advantageously, the direction of displacement during the grinding process is reversible. Advantageously, the carrier, together with the biasing device for the at least one grinding element, is arranged to be moved or advanced in the contact-making direction. Advantageously, the biasing device comprises a spring, for example a helical spring. Advantageously, in the direction of the clothing surface to be ground, a plurality of grinding elements are provided. Advantageously, with each grinding element there is associated a biasing device, to which it has an articulated connection. Advantageously, at least one grinding element carries out an oscillating or reciprocating movement back and forth during the grinding process. Advantageously, the carrier is mounted on the extension bends of a flat card or roller card. Advantageously, the position of the extension bends is adjustable in the radial direction, for example by means of adjusting elements, for example threaded spindles. Advantageously, the position of the extension bends relative to the roller is adjustable. Advantageously, the extension bends are mounted on the side parts. Advantageously, the carrying device is mounted on the side screens of the flat card. Advantageously, the carrying device is mounted on a machined surface, for example of the extension bend. Advantageously, the machined surface, for example of the extension bend, has a defined spacing relative to the central axis of the roller. Advantageously, the carrier has, in each of its end regions, a connecting plate or the like. Advantageously, the movement drive of the grinding device is connected to the machine control system of the flat card or roller card. Advantageously, the movement drive encompasses the advancing movement towards and away from the roller. Advantageously, the movement procedure encompasses the longitudinally directed grinding movement. Advantageously, the duration of grinding is adjustable. Advantageously, the duration of grinding is adjustable in dependence on the usage time (time in operation) of the clothing. Advantageously, the duration of grinding is between about 2 and 120 seconds.
[0014] Advantageously, the plurality of grinding elements, for example, grinding stones, are arranged next to one another, for example, are arranged in a row. Advantageously, small gaps (spacings), for example not more than 1.0 mm, are provided between the grinding elements. Advantageously, the grinding elements, for example grinding stones, have a width of from about 15 to 1500 mm, for example, about 50 mm.
[0015] Advantageously, for the, for example oscillating, movement there is provided an electrical drive element, for example an electric motor; a pneumatic drive element, for example a pneumatic short-stroke cylinder; or a hydraulic drive element. The drive element is advantageously mechanically coupled to the roller drive.
[0016] Advantageously, the inner carrier member, to which the grinding elements are attached, is accommodated and guided in an attachment member. Advantageously, the grinding element is attached to a guide pin. Advantageously, the grinding elements are movable across the width of the work at the same time as the movement member. Advantageously, the carrier is an extruded member, for example of aluminium. Advantageously, the attachment member is an extruded member, for example of aluminium. Advantageously, the dimensions of the carrier and of the cover element or work element are the same or substantially the same. The grinding device may be employed in mobile use. The grinding device may be employed in stationary use. The grinding element may be employed in stationary use. The grinding element may be employed in the shape of a parallelogram, of a parallelepiped (rectangular), or of square shape. Advantageously, the plurality of grinding elements are arranged at an angle with respect to the longitudinal axis of the carrier. Advantageously, the grinding elements overlap one another in the grinding direction. Advantageously, the roller is the cylinder of a flat card or roller card; a licker-in of a flat card or roller card; or a doffer of a flat card or roller card. Advantageously, the machine surface, for example of the extension bend, has a defined spacing relative to the circle of tips of the clothing of the cylinder.
[0017] The invention also provides apparatus at a flat card or roller card for grinding a clothing drawn onto a rotating roller, having a carrying device with at least one grinding element and an advancing device serving to set the grinding element against the clothing, wherein the apparatus comprises a biasing device serving for automatically continuing to push forward the grinding element in a contact-making direction during the grinding procedure, and wherein the carrying device is attached to the flat card or roller card, wherein a plurality of cover elements and/or work elements of the roller are provided, the grinding device with the grinding element and a cover element and/or work element being interchangeable.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] FIG. 1 is a diagrammatic side view of a flat card having a grinding apparatus according to the invention;
[0019] FIG. 2 shows part of a side screen together with a part of an extension bend, on which a grinding apparatus according to the invention and a fixed carding element are mounted;
[0020] FIG. 3 is a diagrammatic side view of a part of the card showing a side screen together with a flexible bend, cylinder, extension bend, fixed carding elements and a grinding apparatus according to the invention;
[0021] FIG. 4 shows an extension bend together with threaded adjusting spindles and a grinding apparatus according to the invention;
[0022] FIG. 5 a is a sectional side view of a grinding apparatus according to the invention, wherein the grinding elements and the cylinder clothing are out of engagement;
[0023] FIG. 5 a 1 is a detail, to an enlarged scale, of the apparatus of FIG. 5 a;
[0024] FIG. 5 b is a top view of and a partial section through the grinding apparatus of the invention according to FIG. 5 a;
[0025] FIG. 5 c is a sectional view, from the front, through the grinding apparatus of the invention according to FIG. 5 a;
[0026] FIG. 6 is a sectional view, from the side, through the grinding apparatus of the invention according to FIG. 5 a , but with the grinding elements and the cylinder clothing in grinding engagement; and
[0027] FIGS. 7 a to 7 d show four practical forms of arrangement for a plurality of grinding elements.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0028] FIG. 1 shows a flat card, for example a TC 03 (Trade Mark) flat card made by Trützschler GmbH & Co. KG of Mönchengladbach, Germany, having a feed roller 1 , feed table 2 , lickers-in 3 a , 3 b , 3 c , cylinder 4 , doffer 5 , stripper roller 6 , nip rollers 7 , 8 , web-guiding element 9 , web funnel 10 , delivery rollers 11 , 12 , revolving card top 13 having card top guide rollers 13 a , 13 b and flats 14 , can 15 and can coiler 16 . The directions of rotation of the rollers are indicated by curved arrows. Reference letter M denotes the centre (axis) of the cylinder 4 . Reference numeral 4 a denotes the clothing and reference numeral 4 b the direction of rotation of the cylinder 4 . Reference letter B denotes the direction of rotation of the revolving card top 13 in the carding position and reference letter C denotes the return transport direction of the flats 14 . Between the licker-in 3 c and the back card top guide roller 13 a there are arranged immobile cover elements or work elements, for example fixed carding elements 27 ′, and between the front card top guide roller 13 b and the doffer 5 there are arranged immobile cover elements or work elements, for example fixed carding elements 27 ″. The arrow A indicates the working direction. The curved arrows drawn inside the rollers denote the directions of rotation of the rollers. Reference numeral 25 denotes a grinding apparatus according to the invention.
[0029] According to FIG. 2 , an approximately semi-circular, rigid side panel 18 is fixed laterally at each end of the machine frame (not shown), on the outside of which panel in the region of the periphery there is concentrically mounted an arcuate supporting element 19 (extension bend), for example using screws, which supporting element has, as supporting surface, a convex outer surface 19 ′ and an underside 19 ″.
[0030] Carding elements 27 ′ have, at both their ends, supporting surfaces, which lie on top of the convex outer surface 19 ′ of the supporting element. Mounted on the underside of the carding segment 27 ′ are carding elements 20 a , 20 b , which have carding clothings 20 ′ a , 20 ′ b . Reference numeral 21 denotes the circle of tips of the clothings. The cylinder 4 has, around its circumference, a cylinder clothing 4 a , for example a saw-tooth clothing. Reference numeral 22 denotes the circle of tips of the cylinder clothing 4 a . The spacing between the circle of tips 21 and the circle of tips 22 is indicated by the reference letter a and is, for example, 0.20 mm. Reference letter b denotes the spacing between the convex outer surface 19 ′ and the circle of tips 22 . Reference r 1 denotes the radius of the convex outer surface 19 ′ and reference r 2 denotes the radius of the circle of tips 22 . The radii r 1 and r 2 intersect in the centre M (see FIG. 1 ) of the cylinder 4 .
[0031] The carding segment 27 ′ according to FIG. 2 consists of a carrier 23 and two carding elements 20 a , 20 b , which are arranged one after the other in the direction of rotation (arrow 4 b ) of the cylinder 4 , the clothings of the carding elements 20 a , 20 b and the clothing 4 a of the cylinder 4 lying opposite to one another.
[0032] The grinding apparatus 25 is arranged next to the carding segment 27 ′, seen in the direction of rotation 4 b of the cylinder 4 . The spring-loaded grinding stone 40 is in grinding engagement with the tips of the cylinder clothing 4 a . An advancing device 33 (see FIG. 5 a ) brings about displacement of the carrying device for the grinding stone in a radial direction with respect to the cylinder axis M in the direction of the arrows C, D (see FIG. 2 ), as a result of which the grinding stone is brought into and out of engagement with the cylinder clothing 4 a.
[0033] In the arrangement shown in FIG. 3 , between lickers-in 3 and card top guide roller 13 a there are three immobile fixed carding elements 27 a , 27 b , 27 c and non-clothed cylinder casing elements 28 a , 28 b , 28 c . The fixed carding elements 27 have a clothing that lies opposite to the cylinder clothing 4 a . The fixed carding elements 27 a to 27 c are attached by way of screws and the cover elements 28 a to 28 c are attached by way of screws (not shown) to an extension bend 19 a or 19 b (in FIG. 3 , only the extension bends 19 a 1 , 19 a 2 on one side of the flat card are shown), which in turn is fastened by way of screws onto the flat card panel 18 a and 18 b (in FIG. 3 , only 18 a is shown) on each side of the flat card. The flexible bends 17 a , 17 b (in FIG. 3 only 17 a is shown) are fastened by way of screws to the side panels 18 a and 18 b , respectively. Reference numeral 24 a denotes the machine frame and reference numeral 30 denotes suction hoods having separating blades. The grinding apparatus 25 according to the invention is mounted between a cover element 28 b and a fixed carding element 27 b on the extension bend 19 a 1 .
[0034] In the arrangement shown in FIG. 4 , the extension bends 19 a 1 , 19 a 2 and 19 b 1 , 19 b 2 are fastened on each side of the flat card to a flat card panel 18 a and 18 b , respectively. Each extension bend 19 a 1 , 19 a 2 and 19 b 1 , 19 b 2 is—in a manner shown in FIG. 4 using the example of the extension bend 19 a 1 —adjustable in the radial direction by means of at least three adjusting spindles 29 a 1 , 29 a 2 , 29 a 3 (threaded spindles). By this means it is possible to adjust the spacing b ( FIG. 2 ) between the convex outer surface 19 ′ and the circle of tips 22 of the clothing 4 a of the cylinder. As a result it is also possible to adjust the spacing between the convex outer surface 19 ′ and the centre M (see FIG. 1 ) of the cylinder 4 . As a result, defined spacings are specified between the peripheral region 19 ′ of the extension bend 19 a 1 and a reference point (circle of tips 22 or centre M). Those defined spacings are utilised for biasing of the biasing device 34 and make separate adjustment of the biasing device unnecessary. The grinding apparatus according to the invention 25 needs only to be set against the clothing 4 a that is to be ground and/or, as appropriate, to be lifted off therefrom, by means of the advancing device.
[0035] The spacing a ( FIG. 2 ) between the clothings of the fixed carding element 27 ′ and the clothing 4 a of the cylinder 4 can also be adjusted by means of the adjusting spindles 29 a 1 , 29 a 2 , 29 a 3 .
[0036] Reference letters f 1 to f 9 denote the widths of the elements mounted on the extension bend 19 a 1 , for example the grinding apparatus 25 , the carding element 27 , the suction hood 30 with separating blade, the widths f 1 to f 9 being the same. The grinding apparatus 25 and a cover element or work element are accordingly interchangeable. It is therefore possible for a cover element or work element to be removed and for a grinding apparatus 25 to be installed in place thereof (exchange). However, it is also possible for the grinding apparatus 25 to be retained permanently mounted on the flat card.
[0037] In FIGS. 5 a to 5 d there is shown in detail one embodiment of the grinding apparatus according to the invention.
[0038] FIG. 5 a shows the cylinder 4 , provided with clothing 4 a , and the grinding apparatus 25 . The grinding apparatus 25 has a housing 31 , in which there are provided a carrying device 32 having grinding elements 40 , an advancing device 33 , a biasing device 34 and a displacement device 47 (see FIG. 5 b ). Reference letter f denotes the width of the housing 31 .
[0039] The carrying device 32 comprises a guide member 35 and a carrier member 36 . Mounted at one end of a guide pin 37 , by way of a universal joint 38 , is a grinding stone carrier 39 having a grinding stone 40 . The guide pin 37 is mounted in a through-hole in the guide member 35 so as to be movable in the direction of the arrows F, G. The other end of the guide pin 37 passes through a through-hole 36 a , 36 b in the carrier member 36 . A securing ring 41 is attached to the end of the guide pin 37 . The guide member 35 and the carrier member 36 are extruded aluminium members. Reference numerals 46 a 1 , 46 a 2 denote guide pins (see FIG. 5 a ).
[0040] The advancing device 33 comprises a pneumatic cylinder 42 having a cylinder rod 43 (piston rod), for example a pneumatic short-stroke cylinder. To the free end of the cylinder rod 43 there is attached a mechanical transmission element 44 , for example a flat sheet metal plate or the like, which is additionally fixed to the carrier member 36 . As a result of this rigid connection, the cylinder rod 43 and the carrier member 36 are both movable in the same direction. That end face of the cylinder 33 which is remote from the cylinder rod 43 is fixed so that it is supported against the guide member 35 . In accordance with that position of the advancing device 33 which is shown in FIG. 5 a , a spacing c is present between the grinding element 40 and the cylinder clothing 4 a , that is to say the grinding elements 40 are not in engagement with the cylinder clothing 4 a.
[0041] The biasing device 34 comprises a helical spring 45 , for example a compression spring, one end of which is supported on a shoulder 37 a of the guide pin 37 and the other end of which is supported on a step 36 c in the hole 36 a through the carrier member 36 .
[0042] Referring to FIG. 5 b , the displacement device 47 comprises a pneumatic cylinder 48 having a cylinder rod 49 (piston rod), for example a pneumatic short-stroke cylinder. At the free end of the cylinder rod 49 there is attached a mechanical transmission element 50 , for example a twice-bent sheet metal plate or the like, which is additionally fixed to the guide member 35 , for example by screws 51 a , 51 b . As a result of this rigid connection, the cylinder rod 49 and the guide member 35 are each movable in the same direction. That end region of the cylinder 48 which is remote from the cylinder rod 49 is fixed so that it is supported against a connecting plate 53 a . The guide member 35 is in the form of an extruded aluminium member, in which, in lateral hollow passageways 35 b , 35 c , there are adhesively bonded pegs 46 , for example steel pegs of circular cross-section. Extending out from each of the two end faces of the guide element 35 are pegs 46 a 1 , 46 a 2 and 46 b 1 , 46 b 2 , which are in the form of guide pins. Sleeves 55 a 1 , 55 a 2 and 55 b 1 , 55 b 2 are fixed in bores 54 a 1 , 54 a 2 and 54 b 1 , 54 b 2 in the connecting plates 53 a and 53 b , respectively. The free ends of the guide pins 46 a 1 , 46 a 2 and 46 b 1 , 46 b 2 engage in the openings of the sleeves 55 a 1 , 55 a 2 and 55 b 1 , 55 b 2 , respectively, in a manner allowing displacement in the direction of the arrows K, L. FIG. 5 c shows different spacings d and e between, on the one hand, those end faces of the connecting plates 53 a , 53 b that face one another and, on the other hand, the end faces 35 d , 35 e of the guide member 35 . By means of the displacement device 47 and displacement of the cylinder rod 49 in the direction of the arrows M, N, the guide member 35 and with it, at the same time, the carrier member 36 are accordingly pushed back and forth in the direction of the arrows K, L.
[0043] According to FIG. 5 c , a plurality of grinding elements 40 a to 40 n , for example grinding stones, are arranged over the width of the grinding apparatus 25 or cylinder 4 next to one another in a row. The spacing g between grinding elements 40 a to 40 c arranged one another is, for example, less than 1.0 mm. The duration of grinding governs the amount of material removed from the clothing 4 a and varies between, for example, 2 and 120 seconds. During the grinding procedure, the grinding elements 40 a to 40 c carry out a reciprocating or oscillating movement back and forth in the directions K, L.
[0044] In the course of advancing (setting against the clothing 4 a ), the advancing device 33 moves in the direction of the arrow G and in the course of the return movement (lifting off from the clothing 4 a ) the advancing device 33 moves in the direction of the arrow F. During movement of the advancing device 33 in the directions F, G, the guide member 35 remains immobile (stationary). In the course of the grinding movement, both the guide member 35 and also the carrier member 36 are moved in the direction of the arrows K, L.
[0045] With reference to FIG. 6 , in contrast to what is shown in FIG. 5 a , the grinding element 40 is in grinding engagement with the clothing 4 a . As a result of actuation of the cylinder 42 , the carrier member 36 is moved in the direction of the arrow I. As a result, the spacing shown in FIG. 5 a 1 as h, between the carrier member 36 and the guide member 35 , has been reduced to the spacing i. At the same time, the spacing between the securing ring 41 and the carrier element 36 has been increased, compared to FIG. 5 a , to the spacing k.
[0046] In the embodiment of FIGS. 7 a to 7 d , the grinding surfaces of the grinding elements 40 a to 40 n are arranged next to one another in a row. In the embodiment of FIG. 7 a , the grinding surfaces of the grinding elements 40 a to 40 n are in the shape of parallelograms. The adjacent edges of the grinding elements 40 a to 40 n form an angle relative to the grinding apparatus P. In the embodiment of FIG. 7 b , the grinding elements 40 a to 40 n are in the shape of parallelepipeds. Those edges of the grinding elements 40 a to 40 n which face one another are oriented parallel to the grinding apparatus P. In the embodiment of FIG. 7 c , the grinding elements 40 a to 40 n are in the shape of parallelepipeds. They have a grinding surface having two short edges a and two long edges b, the ratio a:b being equal to 1:2. The angle of the edges γ with respect to the grinding apparatus P is α=45°. In the embodiment of FIG. 7 d , the grinding surfaces of the grinding elements 40 a to 40 d are of square shape and the edges of the grinding elements 40 a to 40 d are arranged at an angle α with respect to the grinding apparatus P.
[0047] Advantageously, the grinding apparatus 25 can be replaced by a functional component such as an MTT cassette of the flat card or roller card, without having to adjust or orient that device relative to the roller (cylinder 4 ). This means that this device can be used for a particular machine and is factory-calibrated. The grinding apparatus has connecting plates 53 a to 53 b on the right-hand and left-hand sides, by means of which it can be connected directly to the extension bend 10 or to a machined surface on the side panel 18 of the roller 4 . The spacings of the extension bends 19 with respect to the cylinder 4 are always adjusted for supporting functional components such as an MTT cassette, MTT suction hood and cover members. There is accordingly no need for additional fixing arms or for alignment or preadjustment of the grinding device 35 in the machine. The grinding apparatus 25 is suitable for mobile use and for stationary use in a spinning room machine which has rollers with clothings. Preferably, the device remains in the flat card or roller card and the grinding process is specified by the machine control system. The duration of grinding governs the amount of material removed from the clothing and varies between 2 and 120 seconds. This device has one or more grinding elements 40 , which have a reciprocating or oscillating movement. Preferably, the grinding elements 44 are arranged next to one another in a row, it being possible to produce gaps (spacings) between the grinding elements 40 which are as small as possible (<1.0 mm). The grinding elements 40 preferably have a width of from 15 to 1500 mm; in the preferred arrangement, the width is 50 mm. The grinding stones 40 are accommodated in a guide member 35 and are fixed thereto by means of a guide pin 37 and, in the process, mounted on a universal joint. When the number of grinding elements is >1, an oscillating movement is, because of the gaps, required in the longitudinal direction (in the direction of the width of the work) so that all the teeth of the clothing 4 a are uniformly re-ground and activated over the width of the work. That oscillating movement can be accomplished by means of an electrical, electromagnetic, pneumatic or hydraulic drive. Mechanical coupling to the cylinder drive or roller drive is likewise possible. A preferred arrangement has a pneumatic short-stroke cylinder in this location. The guide member 35 , to which the grinding elements are fixed by means of the guide pin, is accommodated and guided in a carrier member 36 . The grinding elements 46 can, at the same time, be moved relative to the carrier member 36 and can be advanced towards or moved away from the clothed roller 4 or clothed component. As a result, the grinding procedure can be switched on and switched off. The duration of grinding is dependent on the usage time of the clothing 4 a and can be varied and controlled. Further preference is given to the grinding device being a part of the machine and the grinding procedure being specified by the control system of the machine. Advantageously, the guide member 35 and the carrier member 36 are extruded members of aluminium, in order to keep down the weight of the components. In addition, the component width f and height (cross-section) correspond approximately to those of an MTT cassette so that, instead of a TwinTop, the grinding device 25 can be installed in a flat card.
[0048] Although the foregoing invention has been described in detail by way of illustration and example for purposes of understanding, it will be obvious that changes and modifications may be practised within the scope of the appended claims. | In an apparatus at a carding machine for grinding a clothing drawn onto a rotating roller, having a carrying device with at least one grinding element, the carrying device is attached to the carding machine. In order to make it possible, by means that are simple in terms of construction and installation, to reduce the preparation time, the grinding device with the at least one grinding element is interchangeable with one of a plurality of cover elements and/or work elements associated with the roller. | 3 |
FIELD OF THE INVENTION
The present invention relates to novel cyclic amine derivative compounds, processes for their preparation, pharmaceutical compositions containing them and their use as medicaments, inter alia for the treatment or alleviation of Prostaglandin E mediated diseases such as pain, glaucoma, ulcerative colitis and osteoporosis.
BACKGROUND OF THE INVENTION
A number of review articles describe the characterization and therapeutic relevance of the prostanoid receptors as well as the most commonly used selective agonists and antagonists; Eicosanoids: From Biotechnology to therapeutic Applications , Folco, Samuelson, Maclouf and Velo eds, Plenum Press, New York, 1996, chap. 14, 137-154 ; “Molecular aspects of the structures and functions of the prostaglandin E receptors” , Journal of Lipid Mediators and Cell Signalling, 1996, 14, 83-87 ; “Function of prostanoid receptors: studies on knockout mice” , Prostaglandins & other Lipid Mediators, 2002, 68-69, 557-573 and “ Prostanoid receptor antagonists: development strategies and therapeutic applications” , British Journal of Pharmacology (2009), 158, 104-145. Prostaglandin E2 (PGE 2 ) is a member of the prostanoid family with a variety of physiological effects, including mucosal protection, induction of gastric acid secretion in stomach, generation of fever, hyperalgesia, inflammation and immunity. These actions of PGE 2 are mediated by four G-protein-coupled PGE 2 receptors, EP 1 , EP 2 , EP 3 and EP 4 .
The EP 4 receptor is a 7-transmembrane receptor whose activation is normally associated with elevation of intracellular cyclic adenosine monophosphate (cAMP) levels. PGE 2 -activated EP 4 receptor signalling may be involved in various pathologic states, such as pain (in particular inflammatory, neuropathic and visceral), inflammation, neuroprotection, cancer, dermatitis, bone disease, immune system dysfunction promotion of sleep, renal regulation, gastric or enteric mucus secretion and duodenal bicarbonate secretion.
In The Journal of Immunology (2008) 181, 5082-5088, studies suggest that PGE 2 inhibits proteoglycan synthesis and stimulates matrix degradation in osteoarthritic chondrocytes via the EP 4 receptor. Targeting EP 4 , rather than cyclooxygenase 2, could represent a future strategy for osteoarthritis disease modification.
In European Journal of Pharmacology (2008) 580, 116-121, studies suggest that a pharmacological blockade of the prostanoid EP 4 receptor may represent a new therapeutic strategy in signs and symptomatic relief of osteoarthritis and/or rheumatoid arthritis.
A number of publications have demonstrated that PGE 2 acting through the EP 4 receptor subtype, and EP 4 agonists alone, can regulate inflammatory cytokines after an inflammatory stimulus. Takayama et al in the Journal of Biological Chemistry (2002) 277, 46, 44147-54, showed that PGE 2 modulates inflammation during inflammatory diseases by suppressing macrophage derived chemokine production via the EP 4 receptor. In Bioorganic & Medicinal Chemistry (2002) 10, 7, 2103-2110, Maruyama et al demonstrate the selective EP 4 receptor agonist ONO-AE1-437 suppresses LPS induced TNF-a in human whole blood whilst increasing the levels of IL-10. An article from Anesthesiology, (2002) 97, 170-176, suggests that a selective EP 4 receptor agonist ONO-AE1-329 effectively inhibited mechanical and thermal hyperalgesia and inflammatory reactions in acute and chronic monoarthritis.
Two independent articles from Sakuma et al in Journal of Bone and Mineral Research (2000) 15, 2, 218-227 and Miyaura et al in Journal of Biological Chemistry (2000) 275, 26, 19819-23, report impaired osteoclast formation in cells cultured from EP 4 receptor knock-out mice. Yoshida et al in Proceedings of the National Academy of Sciences of the United States of America (2002) 99, 7, 4580-4585, by use of mice lacking each of the PGE 2 receptor EP subtypes, identified EP 4 as the receptor that mediates bone formation in response to PGE 2 administration. They also demonstrated a selective EP 4 receptor agonist (ONO-4819) consistently induces bone formation in wild type mice. Additionally, Terai et al in Bone 2005, 37(4), 555-562 have shown the presence of a selective EP 4 receptor agonist (ONO-4819) enhanced the bone-inducing capacity of rhBMP-2, a therapeutic cytokine that can induce bone formation.
Further research by Larsen et al in Acta. Physiol. Scand. (2005) 185, 133-140, shows the effects of PGE 2 on secretion in the second part of the human duodenum is mediated through the EP 4 receptor. Nitta et al in Scandinavian Journal of Immunology (2002), 56, 1, 66-75 has shown that a selective EP 4 receptor agonist ONO-AE 1-329 can protect against colitis in rats.
Dore et al in The European Journal of Neuroscience (2005) 22, 9, 2199-206, have shown that PGE 2 can protect neurons against amyloid beta peptide toxicity by acting on EP 2 and EP 4 receptors. Furthermore Dore has demonstrated in Brain Research (2005) 1066, (1-2), 71-77 that an EP 4 receptor agonist ONO-AE1-329 protects against neurotoxicity in an acute model of excitotoxicity in the brain.
Woodward et al in Journal of Lipid Mediators (1993), 6, (1-3), 545-53, found intraocular pressure could be lowered using selective prostanoid agonists. Two papers in Investigative Ophthalmology & Visual Science have shown the prostanoid EP 4 receptor is expressed in human lens epithelial cells (Mukhopadhyay et al 1999, 40(1), 105-12), and suggest a physiological role for the prostanoid EP 4 receptor in modulation of flow in the trabecular framework of the eye (Hoyng et al 1999, 40(11), 2622-6).
Compounds exhibiting EP 4 receptor binding activity and their uses as agonists have been described in, for example WO2009150118, WO2008136519, WO2008092860, WO2008092861, WO2008092862, WO2006137472, JP2006321737, WO2006052630, WO2006052893, WO2006016689
SUMMARY OF THE INVENTION
One of the objects of the present invention is the provision of compounds having an EP 4 receptor agonistic activity and specifically pharmaceutical compounds which are useful for the treatment or alleviation of Prostaglandin E mediated diseases.
The inventors of the present application have discovered novel compounds that are selective agonists of the EP 4 subtype of PGE 2 receptors. Specifically, the compounds according to the invention are provided with analgesic, antinflammatory, antiglaucoma activity, and also with anti-osteoporosis and antiulcerative activity.
In accordance with a general aspect, the present invention provides cyclic amine compound of Formula (I):
or a pharmaceutically acceptable salt thereof,
wherein:
R 1 and R 2 are independently hydrogen, linear o branched C 1-3 alkyl or joined together
they form a cyclopropyl ring;
n is 1 or 2,
R 3 is hydrogen or a linear or branched (C 1-3 ) alkyl,
R 4 is hydrogen, fluorine, or hydroxy group,
R 5 is halogen, cyano, linear o branched (C 1-3 ) alkyl, trifluoromethyl or trifluoromethoxy,
R 6 is hydrogen or halogen.
The term “halogen” as used herein refers to a fluorine, chlorine, bromine or iodine atom. In certain embodiments the halogen is fluorine.
The term “C 1-3 alkyl” as used herein refers to a linear or branched saturated hydrocarbon group containing of 1 to 3 carbon atoms. Examples of such groups include methyl, ethyl, n-propyl, isopropyl. In certain embodiments the C 1-3 alkyl is CH 3 .
In this invention compounds of Formula (I) may exist as R and S enantiomers and as racemic mixture. This invention includes in its scope of protection all the possible isomers and racemic mixtures. Wherever should be present further symmetry centres, this invention includes all the possible diastereoisomers and relative mixtures as well.
In another aspect the invention concerns a compound of Formula (I) as medicament in particular it concerns its use for the treatment of pathologies where an agonist of the EP 4 receptor is needed, such as the treatment of pain, glaucoma, ulcerative colitis, osteoporosis.
DETAILED DESCRIPTION OF THE INVENTION
The invention thus concerns, in a general aspect, cyclic amine derivatives of Formula (I):
or a pharmaceutically acceptable salt thereof,
wherein:
R 1 and R 2 are independently hydrogen, linear o branched C 1-3 alkyl or joined together
they form a cyclopropyl ring;
n is 1 or 2,
R 3 is hydrogen or a linear or branched C 1-3 alkyl,
R 4 is hydrogen, fluorine, or hydroxy group,
R 5 is halogen, cyano, linear o branched C 1-3 alkyl, trifluoromethyl or trifluoromethoxy,
R 6 is hydrogen or halogen.
In certain embodiments R 6 is in 4-position (para-position).
The term “halogen” as used herein refers to a fluorine, chlorine, bromine or iodine atom. In certain preferred embodiments the halogen is fluorine. In certain embodiments R 6 is fluorine. In certain embodiments both R 5 and R 6 are fluorine.
The term “C 1-3 alkyl” as used herein refers to a linear or branched saturated hydrocarbon group containing of 1 to 3 carbon atoms. Examples of such groups include methyl, ethyl, n-propyl, isopropyl.
In certain embodiments the C 1-3 alkyl is methyl.
In certain embodiments of the invention there is provided a subset (A) of compounds of formula (I) wherein n=1,
R 1 and R 2 are independently hydrogen, linear o branched C 1-3 alkyl or joined together
they form a cyclopropyl ring;
n is 1 or 2,
R 3 is hydrogen or a linear or branched C 1-3 alkyl,
R 4 is hydrogen, fluorine, or hydroxy group,
R 5 is halogen, cyano, linear o branched C 1-3 alkyl, trifluoromethyl or trifluoromethoxy,
R 6 is hydrogen or halogen.
In certain embodiments R 6 is in 4-position (para-position).
In the subset (A) of compounds of formula (I) the terms halogen and C 1-3 alkyl are as defined hereinabove.
In certain embodiments the halogen is fluorine.
In certain embodiments the substituent R 6 is halogen, preferably fluorine.
In certain embodiments the substituent R 6 is in the 4-position.
In certain embodiments the C 1-3 alkyl is methyl.
In certain embodiments R 5 is fluorine, trifluoromethyl or methyl.
In certain embodiments R 6 is hydrogen or fluorine.
In certain embodiments of the subset (A), R 1 is hydrogen; R 2 is methyl; R 3 is hydrogen; R 4 is hydrogen, fluorine or hydroxy; R 5 is fluorine, trifluoromethyl or methyl; R 6 is hydrogen.
In certain embodiments of the invention there is provided a subset (B) of compounds of formula (I) wherein n=2,
R 1 and R 2 are independently hydrogen, linear o branched C 1-3 alkyl or joined together
they form a cyclopropyl ring;
n is 1 or 2,
R 3 is hydrogen or a linear or branched C 1-3 alkyl,
R 4 is hydrogen, fluorine, or hydroxy group,
R 5 is halogen, cyano, linear o branched C 1-3 alkyl, trifluoromethyl or trifluoromethoxy,
R 6 is hydrogen or halogen.
The terms halogen and C 1-3 alkyl are as defined hereinabove.
In certain embodiments the substituent R 6 is halogen, preferably fluorine.
In certain embodiments the substituent R 6 may be in the 4-position.
In certain embodiments the halogen is fluorine.
In certain embodiments the C 1-3 alkyl is methyl.
In certain embodiments R 5 is fluorine, methyl, trifluoromethyl or trifluoromethoxy.
In certain embodiments R 6 is fluorine or hydrogen.
In certain embodiments both R 5 and R 6 are fluorine.
In certain embodiments R 5 is methyl and R 6 is hydrogen.
In certain embodiments of the subset (B) R 1 is hydrogen; R 2 is methyl; R 3 is hydrogen; R 4 is hydrogen; R 5 is fluorine, trifluoromethyl, methyl or trifluoromethoxy, R 6 is hydrogen.
In additional embodiments R 1 is hydrogen; R 2 is methyl; R 3 is hydrogen; R 4 is hydrogen; R 5 is fluorine, methyl, trifluoromethyl, or trifluoromethoxy; R 6 is hydrogen.
The term “pharmaceutically acceptable salts” as used herein, refers to salts prepared from pharmaceutically acceptable non-toxic bases or acids including inorganic or organic bases and inorganic or organic acids, quaternary ammonium salts and internally formed salts.
Salts derived from inorganic bases include aluminium, ammonium, calcium, copper, ferric, ferrous, lithium, magnesium, manganese salts, manganese, potassium, sodium, zinc, and the like. Particularly preferred are the ammonium, calcium, magnesium, potassium, and sodium salts. Salts derived from pharmaceutically acceptable organic non-toxic bases include salts of primary, secondary, and tertiary amines, substituted amines including naturally occurring substituted amines, cyclic amines, and basic ion exchange resins, such as arginine, betaine, caffeine, choline, N,N′-dibenzylethylenediamine, diethylamine, 2-diethyl-aminoethanol, 2-dimethylaminoethanol, ethanolamine, ethylenediamine, N-ethyl-morpholine, N-ethylpiperidine, glucamine, glucosamine, histidine, hydrabamine, isopropylamine, lysine, methyl-glucamine, morpholine, piperazine, piperidine, polyamine resins, procaine, purines, theobromine, triethylamine, trimethylamine, tripropylamine, tromethamine, and the like.
When the compound of the present invention is basic, salts may be prepared from pharmaceutically acceptable non-toxic acids, including inorganic and organic acids. Such acids include acetic, benzenesulfonic, benzoic, camphorsulfonic, citric, ethanesulfonic, fumaric, gluconic, glutamic, hydrobromic, hydrochloric, isethionic, lactic, maleic, malic, mandelic, methanesulfonic, mucic, nitric, pamoic, pantothenic, phosphoric, succinic, sulfuric, tartaric, p-toluenesulfonic acid, and the like. Particularly preferred are citric, hydrobromic, hydrochloric, maleic, phosphoric, sulfuric, and tartaric acids.
It will be understood that, as used herein, references to the compounds of Formula (I) are meant to also include the pharmaceutically acceptable salts.
Furthermore, the compound of the formula (I) may form an acid addition salt or a salt with a base, depending on the kind of the substituents, and these salts are included in the present invention, as long as they are pharmaceutically acceptable salts.
The compounds (I) of the invention may be in crystalline forms. In certain embodiments, the crystalline forms of the compounds (I) are polymorphs.
The terms “the compound of the invention” and “the compounds of the present invention” refer to each of the compounds of formulae (I) and are meant to include their pharmaceutically acceptable salts, hydrates, solvates, and crystalline forms and also any suitable forms as illustrated hereinafter.
In certain embodiments, the compound of the Formula (I) may exist in the form of other tautomers or geometrical isomers in some cases, depending on the kinds of the substituents. In the present specification, the compound may be described in only one form of such isomers, but the present invention includes such isomers, isolated forms of the isomers, or a mixture thereof.
Furthermore, the compound of the Formula (I) may have asymmetric carbon atoms or axial asymmetries in some cases, and correspondingly, it may exist in the form of optical isomers such as an (R)-form, an (S)-form, and the like. The present invention includes both a mixture and an isolated form of these optical isomers.
Within the scope of the present invention are therefore included all stereoisomeric forms, including enantiomers, diastereoisomers, and mixtures thereof, including racemates and the general reference to the compounds of formulae (I) include all the stereoisomeric forms, unless otherwise indicated.
Additionally, the pharmaceutically acceptable prodrugs of the compound of the formula (I) are also included in the present invention. The pharmaceutically acceptable prodrug refers to a compound having a group which can be converted into an amino group, OH, COOH, or the like, by solvolysis or under a physiological condition. Examples of the groups for forming a prodrug include those as described in Prog. Med., 5, 2157-2161 (1985) or “Pharmaceutical Research and Development” (Hirokawa Publishing Company, 1990), vol. 7, Drug Design, 163-198.
Additionally, the present invention in certain embodiments also includes various hydrates or solvates, and polymorphism of the compound of the formula (I) and a pharmaceutically acceptable salt thereof. Furthermore, the present invention also includes the compounds labelled with various radioactive isotopes or non-radioactive isotopes.
Compounds according to the present invention include examples 1-20 as shown herein below, or a pharmaceutically acceptable salt thereof.
In certain embodiments, the present invention provides a compound selected from the group consisting of:
lithium 4-((1S)-1-(1-(3,4-difluorobenzyl)piperidine-2-carboxamido)ethyl)benzoate lithium 4-((1S)-1-(1-(3-methylbenzyl)piperidine-2-carboxamido)ethyl)benzoate lithium 4-((1S)-1-(1-(3-fluorobenzyl)piperidine-2-carboxamido)ethyl)benzoate lithium 4-((1S)-1-(1-(3-(trifluoromethyl)benzyl)piperidine-2-carboxamido)ethyl)benzoate lithium 4-((S)-1-((R)-1-(3-(trifluoromethyl)benzyl)piperidine-2-carboxamido)ethyl)benzoate lithium 4-((S)-1-((R)-1-(3-fluorobenzyl)piperidine-2-carboxamido)ethyl)benzoate lithium 4-((S)-1-((R)-1-(3-methylbenzyl)piperidine-2-carboxamido)ethyl)benzoate lithium 4-((S)-1-((R)-1-(3-(trifluoromethoxy)benzyl)piperidine-2-carboxamido)ethyl)benzoate lithium (R)-4-(1-(1-(3-(trifluoromethyl)benzyl)piperidine-2-carboxamido)cyclopropyl)benzoate lithium (R)-4-(1-(1-(3-methylbenzyl)piperidine-2-carboxamido)cyclopropyl)benzoate lithium (R)-4-(1-(1-(3-fluorobenzyl)piperidine-2-carboxamido)cyclopropyl)benzoate (R)-4-(1-(1-(4-fluoro-3-methylbenzyl)piperidine-2-carboxamido)cyclopropyl)benzoic acid lithium (R)-4-(1-(1-(4-fluoro-3-(trifluoromethyl)benzyl)piperidine-2-carboxamido) cyclopropyl)benzoate lithium 4-((S)-1-((R)-1-(3-fluorobenzyl)pyrrolidine-2-carboxamido)ethyl)benzoate lithium 4-((S)-1-((R)-1-(3-(trifluoromethyl)benzyl)pyrrolidine-2-carboxamido)ethyl)benzoate lithium 4-((S)-1-((R)-1-(3-methylbenzyl)pyrrolidine-2-carboxamido)ethyl)benzoate lithium 4-((S)-1-((R)-1-(3,4-difluorobenzyl)pyrrolidine-2-carboxamido)ethyl)benzoate lithium 4-((S)-1-((R)-2-methyl-1-(3-(trifluoromethyl)benzyl)pyrrolidine-2-carboxamido)ethyl)benzoate lithium 4-((S)-1-((2R,4R)-4-hydroxy-1-(3-(trifluoromethyl)benzyl)pyrrolidine-2-carboxamido)ethyl)benzoate lithium 4-((S)-1-((2R,4S)-4-fluoro-1-(3-(trifluoromethyl)benzyl)pyrrolidine-2-carboxamido)ethyl)benzoate
Preferred compounds of the invention are selected from the group consisting of:
lithium 4-((S)-1-((R)-1-(3-(trifluoromethyl)benzyl)piperidine-2-carboxamido)ethyl)benzoate lithium (R)-4-(1-(1-(3-(trifluoromethyl)benzyl)piperidine-2-carboxamido)cyclopropyl)benzoate (R)-4-(1-(1-(4-fluoro-3-methylbenzyl)piperidine-2-carboxamido)cyclopropyl)benzoic acid lithium (R)-4-(1-(1-(4-fluoro-3-(trifluoromethyl)benzyl)piperidine-2-carboxamido)cyclopropyl)benzoate lithium 4-((S)-1-((R)-1-(3-(trifluoromethyl)benzyl) pyrrolidine-2-carboxamido)ethyl)benzoate lithium 4-((S)-1-((2R,4R)-4-hydroxy-1-(3-(trifluoromethyl)benzyl)pyrrolidine-2-carboxamido)ethyl)benzoate
A further aspect of this invention concerns a process for the preparation of a compound of Formula (I) comprising the following steps represented in the general scheme below:
In the above general scheme, R 1 , R 2 , R 3 , R 4 , R 5 , R 6 and n are as defined in formula (I),
n is 1 or 2
R is selected from the group consisting of hydrogen, linear or branched C 1-3 alkyl and benzyl groups,
W is selected from the group consisting of hydrogen, benzyl group and t-Butyl carbamate group.
It will be appreciated that compounds of formula (II), (IV) and (VII), may be converted into other compounds of formula (II), (IV) and (VII), by synthetic methods known to the skilled person in the art.
Examples of such conversion reactions are:
i) Compounds of formula (II) wherein R is C 1-3 alkyl, may be prepared by reacting corresponding compounds wherein R is hydrogen with alcohols, for example ethanol, in the presence of a suitable reactive reagent such as thionyl chloride.
ii) Compounds of formula (VII), when R is hydrogen, may be prepared by hydrolysis of the corresponding compounds of formula (VII), wherein R is C 1-3 alkyl. The hydrolysis is carried out in the presence of a base, for example lithium hydroxide in aqueous 1,4-dioxane.
iii) Compounds of formula (VII), when R is a substituted benzyl group, may be prepared by fluorination of corresponding compounds of formula (VII), wherein R is hydroxy group. The hydrolysis is carried out in the presence of diethylaminosulfur trifluoride at low temperature, typically −20° C.
Method of Synthesis
As above shown, according to a further aspect of this invention there is provided a process for the preparation of compound of formula (I).
In a more detailed way, the compounds of the present invention may be prepared according to the following schemes.
Unless otherwise indicated R 1 , R 2 , R 3 , R 4 , R 5 , R 6 and n, in the reaction schemes and discussion that follow are as defined above, in formula (I).
The term “protecting group”, as used hereinafter, means an amino protecting group which is selected from typical amino protecting groups as described in Protective Groups in Organic Synthesis edited by T. W. Greene et al. (John Wiley & Sons, 1999);
Compounds of formula (I) may be prepared by hydrolysis reaction of ester compounds of formula (VI) according to the reaction scheme 1.
Hydrolysis can be carried out in presence of a base, for example lithium hydroxide in a suitable solvent such as in aqueous 1,4-dioxane.
In certain embodiments, this reaction may be carried out at room temperature.
Compounds of formula (VI) may be prepared according to reaction scheme 2.
Compounds of formula (IV), wherein W is hydrogen, may be reacted with compounds of formula (V) in the presence of a suitable base, such as cesium carbonate, in a suitable solvent, for example acetonitrile. In certain embodiments the reaction is carried out at room temperature or in others under heating, for example at around 60° C.
Compounds of formula (IV), wherein W is hydrogen, may be prepared from corresponding compounds of formula (IV) wherein W is benzyl group or t-butyl carbamate group.
In certain embodiments wherein W is t-butyl carbamate, the deprotection step can be carried out in presence of trifluoroacetic acid in a suitable solvent such as dichloromethane.
In other embodiments wherein W is a benzyl group, the deprotection step can be carried out by hydrogenolysis typically in a suitable solvent such as ethanol.
Compounds of formula (IV) may be prepared according to reaction scheme 3.
In certain embodiments, the compounds of formula (II), wherein R is hydrogen and W is a benzyl group or t-butyl carbamate, are reacted with compounds of formula (III) in the presence of a suitable coupling reagent, for example selected from (2-(6-Chloro-1H-benzotriazole-1-yl)-1,1,3,3-tetramethylaminium hexafluorophosphate) (HCTU), O-(7-Azabenzotriazol-1-yl)-N,N,N′,N′-tetramethyluronium hexafluorophosphate (HATU), (1-Ethyl-3-(3-dimethyllaminopropyl)carbodiimide hydrochloride) and 1-Hydroxybenzotriazole and mixtures thereof. Typically, the reaction is carried out in an aprotic solvent, for example a halohydrocarbon, such as dichloromethane, N,N-dimethylformamide, or acetonitrile or mixture thereof, typically at room temperature, in presence of a suitable base, such as N,N-diisopropylamine.
Compounds of formula (III) are known, for example from the International Patent applications WO 2005105733 and WO2008104055.
Alternatively compound of formula (VI) may be prepared according to reaction scheme 4.
In certain embodiments, the compounds of formula (VII), wherein R is hydrogen, are reacted with compounds of formula (III) in the presence of a suitable coupling reagent, for example selected from (2-(6-Chloro-1H-benzotriazole-1-yl)-1,1,3,3-tetramethylaminium hexafluorophosphate) (HCTU), O-(7-Azabenzotriazol-1-yl)-N,N,N′,N′-tetramethyluronium hexafluorophosphate (HATU), (1-Ethyl-3-(3-dimethyllaminopropyl)carbodiimide hydrochloride) and 1-Hydroxybenzotriazole or mixtures thereof.
In certain embodiments the reaction is carried out in an aprotic solvent, for example a halohydrocarbon, such as dichloromethane, N,N-dimethylformamide, or acetonitrile or mixtures thereof, typically at room temperature, in presence of a suitable base.
In certain embodiments, the compounds of formula (VII), wherein R is hydrogen, may be prepared by hydrolysis of the corresponding compounds of formula (VII), wherein R is (C 1-3 ) alkyl. In certain embodiments, the hydrolysis is carried out in the presence of a base for example lithium hydroxide, typically in suitable solvent such as aqueous 1,4-dioxane.
In certain embodiments, the compounds of formula (VII) may be prepared according to reaction scheme 5.
In certain embodiments, the compounds of formula (II), wherein R is C 1-3 alkyl or hydrogen and W is hydrogen, may be reacted with compounds of formula (V) in the presence of a suitable base for example cesium carbonate, in a suitable solvent such as acetonitrile. In certain embodiments the reaction is carried out at room temperature, in other embodiments the reaction is carried out under heating, for example at around 60° C.
In accordance with certain embodiments, the compounds of formula (II) wherein W and R 4 are hydrogen, n is 1 and R 3 is methyl, may be prepared according synthetic route described in scheme 6.
According to certain embodiments of the invention, the compounds (I) are obtained using a simple process, easy to scale-up and avoiding lengthy and expensive preparation steps, obtaining high yield of a stable pharmaceutical grade compound of formula (I).
Typically, the various methods described above may be useful for the introduction of the desired group at any stage in the stepwise formation of the required compound, and it will appreciated that these general methods can be combined in different way in such multi-stage processes. Typically, the sequence of the reactions in multi-stage processes are chosen so that the reaction conditions used do not affect groups in the molecule which are in the final product.
In certain embodiments where an enantiomer of a compound of the general formula (I) is required, this may be obtained by resolution of a corresponding enantiomeric mixture of such compound of formula (I) by using conventional methods such as by chiral HPLC procedure.
In certain embodiments the compounds of general formula (I) are in the form of salts, specifically pharmaceutically acceptable salts. These salts may be obtained using conventional methods, for example by reacting the compound having general formula (I) in the form of a free base with a suitable acid in a suitable solvent for example an alcohol, such as ethanol or an ether such as diethyl ether or an ester such as ethyl acetate.
In certain embodiments the compounds of general formula (I) may be isolated in association with solvent molecules for example by evaporation or crystallisation from a suitable solvent to provide the corresponding solvates.
The Inventors have found that the general family of the compounds of formula (I) have affinity for and are specific agonists of PGE 2 receptors, in particular of EP 4 subtype of PGE 2 receptors.
The compounds of general formula (I) are useful in the treatment of Prostaglandin E mediated conditions or diseases.
Thus, according to an additional aspect the invention concerns compounds of Formula (I) for use as a medicament the treatment of pathologies or disorders where an agonist of the EP 4 receptor is needed.
The compounds of formula (I) are EP 4 receptor agonists and may therefore be useful in treating EP 4 receptor mediated diseases.
More particularly, the compounds of the present invention are believed to be of potential use in the treatment or prophylaxis of diseases or disorders where an EP 4 receptor agonist is required such as pain, for example, chronic articular pain (e.g. rheumatoid arthritis, osteoarthritis, rheumatoid spondylitis, gouty arthritis and juvenile arthritis) including the property of disease modification and joint structure preservation; musculoskeletal pain; lower back and neck pain; sprains and strains; neuropathic pain; sympathetically maintained pain; myositis; pain associated with cancer and fibromyalgia; pain associated with migraine; pain associated with influenza or other viral infections, such as the common cold; rheumatic fever; pain associated with functional bowel disorders such as non-ulcer dyspepsia, non-cardiac chest pain and irritable bowel syndrome; pain associated with myocardial ischemia; post operative pain; headache; toothache; and dysmenorrhea.
The compounds may be particularly useful in the treatment of neuropathic pain and symptoms associated therewith. Neuropathic pain syndromes include: diabetic neuropathy; sciatica; non-specific lower back pain; multiple sclerosis pain; fibromyalgia; HIV-related neuropathy; post-herpetic neuralgia; trigeminal neuralgia; and pain resulting from physical trauma, amputation, cancer, toxins or chronic inflammatory conditions. Symptoms of neuropathic pain include spontaneous shooting and lancinating pain, or ongoing, burning pain. In addition, there is included pain associated with normally non-painful sensations such as “pins and needles” (paraesthesias and dysesthesias), increased sensitivity to touch (hyperesthesia), painful sensation following innocuous stimulation (dynamic, static or thermal allodynia), increased sensitivity to noxious stimuli (thermal, cold, mechanical hyperalgesia), continuing pain sensation after removal of the stimulation (hyperpathia) or an absence of or deficit in selective sensory pathways (hypoalgesia).
The compounds may also be useful in the treatment of inflammation, for example in the treatment of skin conditions (e.g. sunburn, burns, eczema, dermatitis, psoriasis); ophthalmic diseases such as glaucoma, retinitis, retinopathies, uveitis and of acute injury to the eye tissue (e.g. conjunctivitis); lung disorders (e.g. asthma, bronchitis, emphysema, allergic rhinitis, respiratory distress syndrome, pigeon fancier's disease, farmer's lung, COPD; gastrointestinal tract disorders (e.g. aphthous ulcer, Crohn's disease, atopic gastritis, gastritis varialoforme, ulcerative colitis, coeliac disease, regional ileitis, irritable bowel syndrome, inflammatory bowel disease, gastrointestinal reflux disease, diarrhea, constipation); organ transplantation; other conditions with an inflammatory component such as vascular disease, migraine, periarteritis nodosa, thyroiditis, aplastic anaemia, Hodgkin's disease, sclerodoma, myaesthenia gravis, multiple sclerosis, sorcoidosis, nephrotic syndrome, Bechet's syndrome, polymyositis, gingivitis, myocardial ischemia, pyrexia, systemic lupus erythematosus, polymyositis, tendinitis, bursitis, and Sjogren's syndrome.
The compounds may also be useful in the treatment of immunological diseases such as autoimmune diseases, immunological deficiency diseases or organ transplantation.
The compounds may also be effective in increasing the latency of HIV infection.
The compounds may also be useful in the treatment of diseases of excessive or unwanted platelet activation such as intermittent claudication, unstable angina, stroke, and acute coronary syndrome (e.g. occlusive vascular diseases).
The compounds may also be useful as a drug with diuretic action, or may be useful to treat overactive bladder syndrome.
The compounds may also be useful in the treatment of impotence or erectile dysfunction.
The compounds of formula (I) may also be useful in the treatment of various Bone Disorders as herein below defined, which includes the treatment of bone fractures, bone injury or bone defects. For example, the compounds of the invention may be useful in enhancement of bone formation i.e. osteogenesis, such as increasing bone mass, bone volume, osteoblast number or osteoblast survival.
The compounds of formula (I) may therefore be useful in the treatment of bone disease, including genetic disorders, that are characterised by abnormal bone metabolism or resorption such as osteoporosis (especially postmenopausal osteoporosis, glucocorticoid induced osteoporosis, hyperthyroidism-induced osteoporosis, immobilisation-induced osteoporosis, heparin-induced osteoporosis and immunosuppressive-induced osteoporosis as well as long term complications of osteoporosis such as curvature of the spine, loss of height and prosthetic surgery), abnormally increased bone turnover, hyper-calcemia (including humoral hypercalcemia), hyperparathyroidism, Paget's bone diseases, osteolysis (including periprosthetic osteolysis), hypercalcemia of malignancy with or without bone metastases, hypercalcemia of fracture healing, rheumatoid arthritis, osteoarthritis (including disease modifying in osteoarthristis such as cartilage/bone repair), ostealgia, osteopenia, calculosis, lithiasis (especially urolithiasis), gout and ankylosing spondylitis, tendonitis, bursitis, malignant bone tumour e.g. osteosarcoma, osteogenesis imperfecta, metastatic bone disease, alveolar bone loss, post-osteomy and childhood idiopathic bone loss.
The compounds of formula (I) may also be useful in bone remodelling and/or promoting bone generation and/or promoting fracture healing. For example, the compounds of the present invention may be useful in fracture healing e.g. long bone fractures and fractures of other bones. The compounds of the present invention may also be useful in healing fractures of the head, face and neck caused e.g. by injury. The compounds of the present invention may also be useful in bone grafting including replacing bone graft surgery entirely, enhancing the rate of successful bone grafts, bone healing following facial reconstruction, maxillary reconstruction, mandibular reconstruction, craniofacial reconstruction e.g. of craniofacial defects such as orofacial defects at birth (including orofacial clefts such as cleft palate), prosthetic ingrowth, vertebral synostosis, long bone extension, spinal fusion, and sternotomy. The compounds of the invention may also be useful in treating bone defects that might evolve around defects that occur during war.
The compounds of the invention may also be useful in periodontal indications such as periodontal disease (periodontitis), tooth loss, and peridontal augmentation e.g. in preparation for tooth implants.
The compounds of the present invention may also be useful in facilitating joint fusion, facilitating tendon and ligament repair, reducing the occurrence of secondary fracture, treating avascular necrosis, facilitating cartilage repair, facilitating bone healing after limb transplantation and repairing damage caused by metastatic bone disease.
The compounds may also be useful for attenuating the hemodynamic side effects of NSAIDs and COX-2 inhibitors.
The compounds may also be useful in the treatment of cardiovascular diseases such as hypertension or myocardial ischemia; functional or organic venous insufficiency; varicose therapy; haemorrhoids; and shock states associated with a marked drop in arterial pressure (e.g. septic shock).
The compounds may also be useful in the treatment of neurodegenerative diseases and neurodegeneration such as dementia, particularly degenerative dementia (including senile dementia, Alzheimer's disease, Pick's disease, Huntingdon's chorea, Parkinson's disease and Creutzfeldt-Jakob disease, ALS, motor neuron disease); vascular dementia (including multi-infarct dementia); as well as dementia associated with intracranial space occupying lesions; trauma; infections and related conditions (including HIV infection); metabolism; toxins; anoxia and vitamin deficiency; and mild cognitive impairment associated with ageing, particularly Age Associated Memory Impairment.
The compounds may also be useful in the treatment of neurological disorders and may be useful as neuroprotecting agents. The compounds may also be useful in the treatment of neurodegeneration following stroke, cardiac arrest, pulmonary bypass, traumatic brain injury, spinal cord injury or the like.
The compounds may also be useful in the treatment of complications of Type 1 diabetes (e.g. diabetic microangiopathy, diabetic retinopathy, diabetic nephropathy, macular degeneration, glaucoma), nephrotic syndrome, aplastic anaemia, uveitis, Kawasaki disease and sarcoidosis.
The compounds may also be useful in the treatment of kidney dysfunction (nephritis, particularly mesangial proliferative glomerulonephritis, nephritic syndrome), liver dysfunction (hepatitis, cirrhosis) and gastrointestinal dysfunction (diarrhoea).
It is to be understood that as used herein any reference to treatment includes both treatment of established symptoms and prophylactic treatment.
It is to be understood that reference to treatment includes both treatment of established symptoms and prophylactic treatment, unless explicitly stated otherwise. In a further aspect, the present invention concerns a compound of Formula (I), for use as a medicament.
In another aspect the invention provides a pharmaceutical composition comprising a compound of Formula (I) and a pharmaceutically acceptable carrier.
The compound of Formula (I) may be used in combination with a pharmaceutically acceptable carrier and, optionally, with suitable excipients, to obtain pharmaceutical compositions.
The term “pharmaceutically acceptable carrier” means solvents, carrier agents, diluting agents and the like which are used in the administration of compounds of the invention.
In certain embodiments, the pharmaceutical compositions of the invention may be in solid or liquid form.
The pharmaceutical compositions in solid form may contain suitable excipients such as fillers, lubricants, binding agents, wetting agents, disintegrants, colorants and flavouring agents and mixtures thereof. For example the tablets may contain pre-gelatinised starch, microcrystalline cellulose, sodium glycolate starch, talc, lactose, magnesium stearate, sucrose, stearic acid, mannitol.
The pharmaceutical compositions in liquid form, typically may be provided as solutions, suspensions, emulsion, syrups, elixir. Typically, the compositions in liquid form may contain suspending agents, emulsifying agents, carriers, preservatives and colorants, flavouring agents.
Typically, the pharmaceutical compositions of the invention can be administered by parenteral, oral, buccal, sublingual, nasal, rectal, topical or transdermal administration. Pharmaceutical compositions for oral administration are generally preferred.
The pharmaceutical compositions of the invention suitable for the oral administration typically, will be discrete units in solid form such as in the form of tablets, capsules, cachets, powders, granules, lozenges, patches, suppositories, pellets, or in liquid form such as liquid preparations, injectable or infusible solutions or suspensions.
The pharmaceutical compositions for parenteral administration typically include sterile preparations in the forms of solutions or suspensions. In certain embodiments the compositions for parenteral administration are aqueous based solution suitable for injection or infusion. In certain embodiments such compositions for parenteral administration includes one or more adjuvants such as buffering agents, preservatives, antibacterial agents, surfactants and mixtures thereof.
The pharmaceutical compositions for topical administration may be formulated as creams, pastes, oils, ointments, emulsions, foams, gels, drops, spray solutions and transdermal patches.
In certain embodiments the pharmaceutical composition of the invention includes 0.1 to 99% by weight of the compound of formula (I) as active ingredient. In certain embodiments the amount of the compound of formula (I) is 1 to 30% by weight.
The dosage of the compound of formula (I) to be administered depends on the severity of the disease, the weight, the age and general conditions of the patient in need of treatment.
For example a suitable unit dosage may vary of from 0.01 to 1000 mg or typically of 1.0 to 300 mg to be administered one or more in a day, for example twice a day usually at regular intervals. The duration of the therapy depends on the severity of the illness and general condition of the patients and may be varied by the physician an extended for certain weeks or months.
According to another aspect, the use of a compounds of the general formula (I) for the manufacture of a medicament for the treatment of pathologies or diseases which require the administration of an agonist of the EP 4 receptor, such as the treatment of inflammatory pain, osteoarthritis, arthritis.
In accordance to certain embodiments, the present invention provides for a pharmaceutical composition comprising a compound of formula (I) in association with an additional active ingredient and a pharmaceutically acceptable excipient.
Said additional active ingredients may be an additional compound of formula (I) or a different chemical entity having similar or different activity.
In certain embodiments said additional active ingredients is selected from the antinflammatory compounds, such as FANS or cortisonic compounds.
The invention will be now detailed by means of the following examples relating to the preparation of some embodiments of the compounds of the invention and to the evaluation of their activity against EP 4 receptor.
The following Descriptions relating to intermediate products and Examples illustrating the preparation of certain compounds of formula (I) or salts thereof follow below. The descriptions illustrate the preparation of intermediates used to make compounds of formula (I) or salts thereof.
In the procedures that follow, after each starting material, reference to a description is provided. This is provided merely for assistance to the skilled chemist. The starting material may not necessarily have been prepared from the Description referred to. The stereochemistry of Descriptions and Examples has been assigned on the assumption that the absolute configuration centres are retained.
The yields are calculated assuming that products were 100% pure if not stated otherwise.
Compound are named using ChemBioDraw Ultra 12.0 (CambridgeSoft Corp., 100 CambridgePark Drive, Cambridge, Mass. 02140)
Reagents used in the following examples were commercially available from various suppliers (for example Sigma-Aldrich, Acros, Matrix scientific, Manchester or Apollo) and used without further purifications.
Reactions in anhydrous environment were run under a positive pressure of dry N2 and solvents were used in dry form.
For reaction involving microwave irradiation, an Initiator 2.5 System was used.
Purification was performed using Biotage automatic flash chromatography systems (Sp1 and Isolera systems), Companion CombiFlash (ISCO) automatic flash chromatography, Flash Master or Vac Master systems.
Flash chromatography was carried out on silica gel 230-400 mesh (supplied by Merck AG Darmstadt, Germany), Varian Mega Be—Si pre-packed cartridges, pre-packed Biotage silica cartridges (e.g. Biotage SNAP-Si cartridges), Waters PoraPak RXN RP cartridges, Biotage SNAP-C18.
SPE-Si cartridges are silica solid phase extraction columns.
PoraPakRXN RP cartridges are polimer based reverse phase resin.
Biotage SNAP C18 Gold cartridges are silica based reverse phase column. SPE-SCX cartridges are ion exchange solid phase extraction columns supplied by Varian. The eluent used with SPE-SCX cartridges is dichloromethane and methanol or only methanol followed by 2N ammonia solution in methanol. The collected fractions are those eluted with ammonia solution in methanol.
Thin layer chromatography was carried out using Merck TLC plates Kieselgel 60F-254, visualized with UV light, aqueous permanganate solution, iodine vapours.
Proton Nuclear Magnetic Resonance (1H NMR) spectra were recorded on Bruker Avance 400 MHz instrument and on Bruker Avance III plus 400 MHz. TMS was used as internal standard. Chemical shifts are reported in ppm (δ) using the residual solvent line as internal standard. Splitting patterns are designated as: s, singlet; d, doublet; t, triplet; q, quartet; m, multiplet; b, broad signal. The NMR spectra were recorded at temperature ranging from 25° C. to 90° C. When more than one conformer was detected the chemical shifts of the most abundant one is usually reported.
In the analytical characterisation of the described compounds “MS” refers to Mass Spectra taken by Direct infusion Mass or to a mass Spectra associated with peaks taken by UPLC/MS or HPLC/MS analysis, where the Mass Spectrometer used is as mentioned below.
Direct infusion Mass Spectra (MS) were run on a Ion Trap Thermo LCQ classic spectrometer, operating in positive ES (+) and negative ES (−) ionization mode using different columns and operating procedures listed below:
Phenomenex Gemini-NX C18 column (100×2 mm, 3 μm particle size), column T=35° C. Mobile phase: A (water+0.1% formic acid)/B (acetonitrile+0.1% formic acid), Gradient: 10% B at t=0 min up to 90% B at t=12 min using different gradient curves, flow rate: 0.3 ml/min;
Acquity™ UPLC-BEH C18 column (50×21 mm, 1.7 μM particle size), column T=35° C. Mobile phase: A (water+0.1% formic acid)/B (acetonitrile+0.1% formic acid), Gradient: 5% B at t=0 min up to 100% B at t=4.5 min, using different gradient curves, flow rate: 0.5 ml/min;
Zorbax SB C18 column (2.1×50 mm, 3.5 μm particle size) column T=35° C. Mobile phase: A (water+0.1% formic acid)/B (acetonitrile+0.1% formic acid), Gradient: 10% B at t=0 min up to 90% B at t=12 min using different gradient curves, flow rate: 0.4 ml/min.
HPLC spectra were performed on a Waters Alliance 2965 instrument equipped with a Waters 2996 UV-Vis detector using a Phenomenex Luna C18 column (150×4.6 mm, 5 μm particle size). [Mobile phase: different mixtures of acetonitrile/methanol/KH2PO4 (20 mM pH 2.5); Elution time: 35 min; column T=30° C.; flow rate=0.6 ml/min. UV detection wavelength range from 220 up to 300 nm]
Total ion current (TIC) and DAD UV chromatografic traces together with MS and UV spectra were taken on a UPLC/MS Acquity™ system equipped with 2996 PDA detector and coupled to a Waters Micromass ZQ™ Mass Spectrometer operating in positive or negative electrospray ionisation mode. UPLC analysis were performed using an Acquity™ UPLC-BEH C18 column (50×21 mm, 1.7 μM particle size), column T=35° C. Mobile phase: A (water+0.1% formic acid)/B (acetonitrile+0.1% formic acid), Gradient: 5% B at t=0 min, up to 100% B at t=2 min or 4.5 min using different gradient curves, flow rate: 0.5 ml/min.
LCMS were taken on a quadrupole Mass spectrometer on Agilent LC/MSD 1200 Series using Column: Welchrom XB-C18 (50×4.6 mm, 5 μm) operating in ES (+) or (−) ionization mode at T=30° C. and with a flow rate=1.5 ml/min.
HPLC spectra for chiral purity determinations were performed on Agilent 1200 instrument and UV detector DAD G1315D using a Daicel Chiralpack IC column (250×4.6 mm, 5 μm particle size) or a Daicel Chiralpack AD-H column (250×4.6 mm, 5 μm particle size). [Mobile phases: isocratic mixtures A (70% n-heptane 30% ethanol+0.1% trifluoroacetic acid) or B (80% n-hexane 20% isopropanol+0.2% trifluoroacetic acid), up to 60 min of elution at 30° C., flow rate of 0.5 ml/min].
Purifications by means of preparative chiral HPLC were performed on Shimadzu Preparative Liquid Chromatograph LC-8A apparatus and UV detector SPD-20A using a Daicel Chiralpack IC column (2×25 cm, 5 μm particle size) or a Daicel Chiralpack AD-H column (2×25 cm, 5 μm particle size).
[Mobile phases: isocratic premixed mixtures A (70% n-heptane 30% ethanol+0.1% trifluoroacetic acid) or B (80% n-hexane 20% isopropanol+0.2% trifluoroacetic acid).
Specific Mobile phase and operating conditions will be specified each time.
ABBREVIATIONS
BAIB—bis(acetoxy)iodobenzene
BF 3 .OEt 2 —Boron trifluoride diethyl etherate
Boc 2 O—Di-tert-butyl dicarbonate
cHex—Cyclohexane
s-BuLi—sec-Butyllithium
t-Buli—tert-Butyllithium
DAST—Diethylaminosulfur trifluoride
1,2 DCE—1,2-Dichloroethane
DCM—dichloromethane
DEA—diethylamine
DMAP—4-Dimethylaminopyridine
DMF—Dimethylformamide
DIPEA—N,N-Diisopropylethylamine
EDC HCl—1-ethyl-3-(3-dimethylaminopropyl)carbodiimide)
EtOAc—Diethylacetate
Et 2 O—Diethylether
Et 3 SiH—Triethylsilane
HATU—O-(7-azabenzotriazol-1-yl)-N,N,N′,N′-tetramethyluronium hexafluorophosphate
HBTU—O-Benzotriazole-N,N,N′,N′-tetramethyl-uronium-hexafluorophosphate
HCTU—(2-(6-Chloro-1H-benzotriazole-1-yl)-1,1,3,3-tetramethylaminium hexafluorophosphate)
HOBT—N-Hydroxybenzotriazole
IPA—2-propanol
LDA—Lithium diisopropylamide
LiEt 3 BH—Lithium triethylborohydride
LiHMDS—Lithium bis(trimethylsilyl)amide
MeCN—Acetonitrile
MTBE—Methyl tert-butyl ether
NaBH(OAc) 3 —Sodium triacetoxyborohydride
NaBH 4 —Sodium borohydride
PTSA—p-Toluene sulfonic acid
Py—Pyridine
RT—Room Temperature
TBAF—Tetra-n-butylammonium fluoride
TBDMSCl—tert-Butyldimethylsilyl chloride
TBDPSCl—tert-butyldiphenylsilyl chloride
TEA—Triethylamine
TEMPO—2,2,6,6-Tetramethylpiperidinyloxy
TFA—Trifluoroacetic acid
TFAA—Trifluoroacetic anhydride
TMEDA—Tetramethylethylenediamine
TMSCHN2— Trimethylsilyldiazomethane
p-TSA—p-Toluenesulfonic acid
THF—Tetrahydrofuran
DESCRIPTIONS
Description 1: (7aR)-3-(trichloromethyl)tetrahydropyrrolo[1,2-c]oxazol-1(3H)-one (D1)
To a solution of D-proline (0.4 g, 3.48 mmol) in MeCN (8 ml) the trifluoroacetaldehyde (0.68 ml, 6.94 mmol) was added and the resulting mixture was stirred at RT for 8 hrs. Solvents were evaporated and the residue was triturated with diethyl ether. After solvent filtration and drying, 0.23 g of title compound (D1) was isolated.
MS: (ES/+) m/z: 244.0 [MH + ] C7H8Cl3NO2 requires 242.96
1 H NMR (400 MHz, CHCl3-d) δ (ppm): 4.15 (dd, J=4.5, 8.6 Hz, 1H), 3.52-3.36 (m, J=7.0, 7.0, 10.5 Hz, 1H), 3.22-3.07 (m, 1H), 2.33-2.20 (m, 1H), 2.19-2.08 (m, 1H), 1.96 (quind, J=5.9, 12.1 Hz, 1H), 1.84-1.69 (m, 1H), 1.61 (br. s., 1H).
Description 2: (7aR)-7a-methyl-3-(trichloromethyl)tetrahydropyrrolo[1,2-c]oxazol-1(3H)-one (D2)
To a solution of (7aR)-3-(trichloromethyl)tetrahydropyrrolo[1,2-c]oxazol-1(3H)-one (D1) (0.2 g, 0.82 mol) in THF (10 ml) cooled at −78° C. LDA 2M sol in THF/heptane (0.58 ml, 1.17 mol) was added and the mixture stirred 30 min. Diiodomethane (0.185 ml, 2.97 mol) was added and the temperature was allowed to warm to −40° C. over a period of 2 hrs then left at this temperature for an additional hour. The resulting mixture was partitioned between DCM and H 2 O. The aqueous phase was extracted with DCM (2×10 ml); the organic phases were collected, dried over Na 2 SO 4 and evaporated in vacuo. The residue was purified by SPE-Si cartridge (25 g) eluting with DCM. Collected fractions after solvent evaporation afforded title compound (D2) in mixture (4:1) with starting material (110 mg).
MS: (ES/+) m/z: 258.0 [MH + ] C8H10Cl3NO2 requires 256.98
Description 3: (R)-methyl 2-methylpyrrolidine-2-carboxylate hydrochloride (D3)
To a solution of (7aR)-7a-methyl-3-(trichloromethyl)tetrahydropyrrolo[1,2-c]oxazol-1(3H)-one (D2) (0.11 g, 0.42 mol) in dry MeOH (2 ml), HCl 1M sol in MeOH (0.3 ml, 0.85 mol) was added and the mixture refluxed under a constant current of nitrogen for 1 h. Solvent was evaporated to afford the title compound (D3) 60 mg.
MS: (ES/+) m/z: 144.1 [MH + ] C7H13NO2 requires 143.09 (as free base).
General Procedure for Amides Preparation
Selected acid (1 eq), HOBT.H 2 O (1 eq) and EDC.HCl (1.5 eq) were suspended in DCM and the resulting mixture was stirred 1 h at RT. A solution of a selected amine (1 eq) and TEA (1 eq) in DCM was added and the mixture was stirred at RT for 1/48 hrs. Solvents were evaporated in vacuo and the resulting residue was re-dissolved in DCM. The mixture was then added to a saturated aqueous solution of NaHCO 3 and extracted with dichloromethane. The organic phase was dried over Na 2 SO 4 and the solvent was removed under reduced pressure. The crude material was purified on SPE-Si cartridge or SNAP-Si column eluting with a mixture of DCM/MeOH 98:2 or DCM/EtOAc from 100:0 to 70:30 affording the title amide compound.
Description 4: tert-butyl 2-(((S)-1-(4-(methoxycarbonyl)phenyl)ethyl)carbamoyl)piperidine-1-carboxylate (diastereoisomers mixture) (D4)
The title compound (D4) (1.95 g) was prepared according to the general procedure for amides preparation starting from 1-(tert-butoxycarbonyl)piperidine-2-carboxylic acid (1.17 g, available from Sigma Aldrich #495875), and (S)-methyl 4-(1-aminoethyl)benzoate hydrochloride (1.1 g, for preparation see published International Patent application WO 2005/105733). Reaction time: 18 hrs.
MS: (ES/+) m/z: 391.3 [MH + ] C21H30N2O5 requires 390.22
Chiral HPLC [Phenomenex Lux Cellulose-1; Mobile phase A: 90% n-hexane (+0.1% DEA), B: 10% IPA; DAD: 237 nm]: Peak 1 retention time: 11.6 min; peak 2 retention time: 16.16 min.
1 H NMR (400 MHz, CHCl3-d) δ (ppm): 8.01 (d, 4H) 7.36 (t, 4H) 6.12-6.82 (m, 2H) 5.17 (br. s., 2H) 4.74 (br. s., 2H) 3.81-4.25 (m, 8H) 2.81 (br. s., 1H) 2.66 (t, 1H) 2.28 (br. s., 2H) 1.42-1.75 (m, 4H).
Description 5: (R)-tert-butyl 2-(((S)-1-(4-(methoxycarbonyl)phenyl)ethyl)carbamoyl)piperidine-1-carboxylate (D5)
The title compound (D5) (405 mg) was prepared according to the general procedure for amides preparation starting from (R)-1-(tert-butoxycarbonyl)piperidine-2-carboxylic acid (250 mg, available from Sigma Aldrich #516341), and (S)-methyl 4-(1-aminoethyl)benzoate hydrochloride (235 mg). Reaction time: 18 hrs.
MS: (ES/+) m/z: 391.3 [MH + ] C21H30N2O5 requires 390.22
Chiral HPLC [Phenomenex Lux Cellulose-1; Mobile phase A: 90% n-hexane (+0.1% DEA), B: 10% EtOH; DAD: 237 nm]: Peak retention time: 9.6 min.
1 H NMR (400 MHz, CHCl3-d) δ (ppm): 8.02 (d, J=8.3 Hz, 2H), 7.36 (d, J=7.8 Hz, 2H), 6.75-6.40 (m, 1H), 5.23-5.11 (m, 1H), 4.81-4.70 (m, 1H), 4.10-3.95 (m, 1H), 3.93 (s, 3H), 2.72-2.60 (m, 1H), 2.36-2.20 (m, 1H), 1.67-1.61 (m, 1H), 1.58-1.47 (m, 15H), 1.46-1.36 (m, 1H).
Description 6: (R)-cert-butyl 2-((1-(4-(methoxycarbonyl)phenyl)cyclopropyl)carbamoyl)piperidine-1-carboxylate (D6)
The title compound (D6) (650 mg) was prepared according to the general procedure for amides preparation starting from (R)-1-(tert-butoxycarbonyl)piperidine-2-carboxylic acid (500 mg, available from Sigma Aldrich #516341), and methyl 4-(1-aminocyclopropyl)benzoate hydrochloride (470 mg). Reaction time: 18 hrs.
MS: (ES/+) m/z: 403 [MH + ] C22H30N2O5 requires 402.22
Chiral HPLC [DAICEL OD-H; Mobile phase A: 80% n-hexane (+0.1% DEA), B: 20% IPA; DAD: 248 nm]: Peak retention time: 13.04 min.
1 H NMR (400 MHz, CHCl3-d) δ (ppm): 7.96 (d, J=8.1 Hz, 2H), 7.24 (d, J=8.1 Hz, 2H), 7.02-6.74 (m, 1H), 4.81-4.68 (m, 1H), 4.19-4.00 (m, 1H), 3.92 (s, 3H), 2.88-2.69 (m, 1H), 2.39-2.17 (m, 1H), 1.66 (br. s., 3H), 1.52 (s, 9H), 1.34 (d, J=18.6 Hz, 6H).
Description 7: (R)-tert-butyl 2-(((S)-1-(4-(methoxycarbonyl)phenyl)ethyl)carbamoyl)pyrrolidine-1-carboxylate (D7)
The title compound (D7) (815 mg) was prepared according to the general procedure for amides preparation starting from (R)-1-(tert-butoxycarbonyl)pyrrolidine-2-carboxylic acid (500 mg, available from Sigma Aldrich #433818), and (S)-methyl 4-(1-aminoethyl)benzoate hydrochloride (501 mg). Reaction time: 18 hrs
MS: (ES/+) m/z: 377 [MH + ] C20H28N2O5 requires 376.20
Chiral HPLC [Phenomenex Lux Cellulose-1; Mobile phase A: 70% n-hexane (+0.1% DEA), B: 30% EtOH; DAD: 254 nm]: Peak retention time: 7.93 min.
1 H NMR (400 MHz, CHCl3-d) δ (ppm): 8.00 (d, J=7.3 Hz, 2H), 7.80-7.53 (m, 1H), 7.35 (d, J=8.3 Hz, 2H), 5.15 (br. s., 1H), 4.35 (br. s., 1H), 3.93 (s, 3H), 3.37 (br. s., 2H), 2.07 (s, 4H), 1.50 (s, 12H).
General Procedure for Substituted Benzyl Amines Preparation
To a solution of selected cyclic amino-acid, cyclic amino-ester or cyclic amino-amide (1 eq) in ACN, Na 2 CO 3 or Cs 2 CO 3 (1.2-8 eq) and selected benzyl bromide (2 eq) were added sequentially and the resulting mixture was heated at 60-68° C. for 4-24 hrs or stirred at RT 18 hrs. After filtration of solids, the filtrate was evaporated in vacuo. The resulting residue was taken up in EtOAc and the organic phase was washed with water, dried over Na 2 SO 4 and evaporated in vacuo. The crude material was purified on SPE-Si cartridge or Biotage SNAP-Si column eluting with mixtures of cHex/EtOAc or cHex/DCM or DCM/EtOAc affording the title substituted benzyl amine compound.
Description 8: (2R,4R)-3-(trifluoromethyl)benzyl 4-hydroxy-1-(3-(trifluoromethyl)benzyl)pyrrolidine-2-carboxylate (D8)
The title compound (D8) (1.02 g) was prepared according to the general procedure for substituted benzyl amines preparation starting from cis-4-Hydroxy-D-proline (4.0 g; available from Aldrich#H5877) and 3-(Trifluoromethyl)benzyl bromide (9.37 ml). (Na 2 CO 3 : 2.5 eq; Reaction time: 24 hrs; 60° C.).
MS: (ES/+) m/z: 448.2 [MH + ] C21H19F6NO3 requires 447.13
1 H NMR (400 MHz, CHCl3-d) δ (ppm): 7.70-7.34 (m, 8H), 5.28-5.06 (m, 2H), 4.51 (br. s., 1H), 4.02 (d, J=13.3 Hz, 1H), 3.81-3.64 (m, 2H), 3.34 (dd, J=5.4, 10.1 Hz, 1H), 2.52 (dd, J=2.9, 10.1 Hz, 1H), 2.30 (td, J=7.0, 13.6 Hz, 1H), 2.23-2.10 (m, 1H), 1.76 (br. s., 1H).
Description 9: (2R,4S)-3-(trifluoromethyl)benzyl 4-fluoro-1-(3-(trifluoromethyl)benzyl)pyrrolidine-2-carboxylate (D9)
A solution of (2R,4R)-3-(trifluoromethyl)benzyl 4-hydroxy-1-(3-(trifluoromethyl)benzyl)pyrrolidine-2-carboxylate (D8) (200 mg, 0.45 mmol) in DCM (20 ml) cooled at −20° C. was treated with DAST (0.148 ml, 1.11 mmol) and the mixture was first stirred 1 h at −20° C. then 18 hrs at RT. The reaction was quenched with NaHCO 3 sat. sol. and the aqueous phase extracted with DCM (3×5 ml), dried over MgSO 4 and evaporated. The residue was purified by Biotage SNAP-Si column (25 g) eluting with petroleum ether/EtOAc from 90/10 to 80/20. Collected fractions, after solvent evaporation afforded the title compound (D9) (110 mg)
MS: (ES/+) m/z: 450.2 [MH + ] C21H18F7NO2 requires 449.12
Chiral HPLC [Daicel OD-H; Mobile phase A: 80% n-hexane (+0.1% DEA); B: 20% IPA; DAD: 265 nm]: Peak retention time: 10.82 min.
1 H NMR (400 MHz, CHCl3-d) δ (ppm): 7.77-7.36 (m, 8H), 5.37-5.04 (m, 3H), 4.14 (d, J=13.3 Hz, 1H), 3.77-3.58 (m, 1H), 3.46 (br. s., 1H), 3.38-3.17 (m, 1H), 2.86-2.49 (m, 2H), 2.49-2.25 (m, 1H).
Description 10: (R)-methyl 2-methyl-1-(3-(trifluoromethyl)benzyl)pyrrolidine-2-carboxylate (D10)
The title compound (D10) (47 mg) was prepared according to the general procedure for substituted benzyl amines preparation starting from (R)-methyl 2-methylpyrrolidine-2-carboxylate hydrochloride (D3) (60 mg, 0.33 mmol) and 3-(Trifluoromethyl)benzyl bromide (0.076 ml, 0.50 mmol). (Na 2 CO 3 : 3 eq; Reaction time: 8 hrs; 60° C.).
MS: (ES/+) m/z: 302.2 [MH + ] C15H18F3NO2 requires 301.13
General Procedure for t-Butyl Carbamate (Boc) Cleavage
To an ice cooled solution of Boc protected amine in DCM a 3:1 mixture TFA:DCM was added and the resulting mixture was stirred at RT 1 h prior evaporation of solvents. The residue was loaded onto SPE-SCX cartridge. The collected ammonia fractions after solvent evaporation afforded the title compounds.
Description 11: methyl 4-((1S)-1-(piperidine-2-carboxamido)ethyl) (diastereoisomers mixture) (D11)
The title compound (D11) (1.37 g) was prepared according to the general procedure for t-Butyl carbamate (Boc) cleavage starting from tert-butyl 2-(((S)-1-(4-(methoxycarbonyl)phenyl)ethyl)carbamoyl)piperidine-1-carboxylate (D4) (1.95 g).
MS: (ES/+) m/z: 291.3 [MH + ] C16H22N2O3 requires 290.16
1 H NMR (400 MHz, CHCl3-d) δ (ppm): 8.01 (d, 2H) 7.38 (d, 2H) 7.13-7.27 (m, 1H) 5.08-5.24 (m, 1H) 3.93 (s, 3H) 3.22-3.38 (m, 1H) 3.05 (d, 1H) 2.72 (t, 1H) 2.50 (br. s., 1H) 1.98 (d, 1H) 1.80 (d, 1H) 1.60 (br. s., 1H) 1.50 (d, 3H) 1.38-1.48 (m, 3H).
Description 12: methyl 4-((S)-1-((R)-piperidine-2-carboxamido)ethyl)benzoate (D12)
The title compound (D12) (286 mg) was prepared according to the general procedure for t-Butyl carbamate (Boc) cleavage starting from (R)-tert-butyl 2-(((S)-1-(4-(methoxycarbonyl)phenyl)ethyl)carbamoyl)piperidine-1-carboxylate (D5) (405 mg).
MS: (ES/+) m/z: 291.3 [MH + ] C16H22N2O3 requires 290.16
Chiral HPLC [Phenomenex Lux Cellulose-1; Mobile phase A: 90% n-hexane (+0.1% DEA), B: 10% EtOH; DAD: 237 nm]: Peak retention time: 15.93 min.
1 H NMR (400 MHz, CHCl3-d) δ (ppm): 8.02 (d, 2H) 7.39 (d, 2H) 7.15 (d, 1H) 5.17 (t, 1H) 3.93 (s, 3H) 3.17-3.33 (m, 1H) 3.03 (d, 1H) 2.71 (br. s., 1H) 1.89-2.08 (m, 1H) 1.72-1.86 (m, 1H) 1.54-1.67 (m, 2H) 1.50 (d, 3H) 1.30-1.46 (m, 3H).
Description 13: (R)-methyl 4-(1-(piperidine-2-carboxamido)cyclopropyl)benzoate (D13)
The title compound (D13) (490 mg) was prepared according to the general procedure for t-Butyl carbamate (Boc) cleavage starting from (R)-tert-butyl 2-((1-(4-(methoxycarbonyl)phenyl)cyclopropyl)carbamoyl)piperidine-1-carboxylate (D6) (650 mg).
MS: (ES/+) m/z: 303.2 [MH + ] C17H22N2O3 requires 302.16
Description 14: methyl 4-((S)-1-((R)-pyrrolidine-2-carboxamido)ethyl)benzoate (D14)
The title compound (D14) (550 mg) was prepared according to the general procedure for t-Butyl carbamate (Boc) cleavage starting from (R)-tert-butyl 2-(((S)-1-(4-(methoxycarbonyl)phenyl)ethyl)carbamoyl)pyrrolidine-1-carboxylate (D7) (815 mg)
MS: (ES/+) m/z: 277.6 [MH + ] C15H20N2O3 requires 276.15
Chiral HPLC [Phenomenex Lux Cellulose-1; Mobile phase A: 70% n-hexane (+0.1% DEA), 30% EtOH; DAD: 240 nm]: Peak retention time: 8.65 min.
1 H NMR (400 MHz, CHCl3-d) δ (ppm): 8.00 (d, J=7.3 Hz, 2H), 7.80-7.53 (m, 1H), 7.35 (d, J=8.3 Hz, 2H), 5.15 (br. s., 1H), 4.35 (br. s., 1H), 3.93 (s, 3H), 3.37 (br. s., 2H), 2.07 (s, 4H), 1.50 (s, 12H).
General Procedure for Esters Hydrolysis
To a solution of the selected ester (1 eq) in dioxane/water (1:1), LiOH H 2 O (1.2-4 eq) was added and the resulting mixture was stirred at RT. Organic solvent was evaporated off and the aqueous solution was washed with DCM and evaporated in vacuo. The residue was loaded on a C18 cartridge eluting with H 2 O/MeOH 9/1 then MeOH. Collected methanolic phases were evaporated off affording the title compound as lithium salt.
Description 15: lithium (2R,4R)-4-hydroxy-1-(3-(trifluoromethyl)benzyl)pyrrolidine-2-carboxylate (D15)
The title compound (D15) (16 mg) was prepared according to the general procedure for esters hydrolysis starting from (2R,4R)-3-(trifluoromethyl)benzyl 4-hydroxy-1-(3-(trifluoromethyl)benzyl)pyrrolidine-2-carboxylate (D8) (50 mg). (LiOH: 2 eq; Reaction time: 4 hrs).
MS: (ES/+) m/z: 290.2 [M-Li+2H + ] C13H13F3LiNO3 requires 295.10
1 H NMR (400 MHz, MeOH-d4) δ (ppm): 7.77 (br. s, 1H), 7.71-7.63 (m, 1H), 7.58-7.45 (m, 2H), 4.41-4.28 (m, 1H), 4.22-4.09 (m, 1H), 3.47-3.41 (m, 1H), 3.31-3.27 (m, 1H), 3.23-3.13 (m, 1H), 2.23-2.09 (m, 2H), 2.07-1.96 (m, 1H).
Description 16: lithium (2R,4S)-4-fluoro-1-(3-(trifluoromethyl)benzyl)pyrrolidine-2-carboxylate (D16)
The title compound (D16) (60 mg) was prepared according to the general procedure for esters hydrolysis starting from (2R,4S)-3-(trifluoromethyl)benzyl 4-fluoro-1-(4-(trifluoromethyl)benzyl)pyrrolidine-2-carboxylate (D9) (110 mg). (LiOH: 2 eq; Reaction time: 18 hrs)
MS: (ES/+) m/z: 292.2 [M-Li+2H + ] C13H12F4LiNO2 requires 297.10
Description 17: lithium (R)-2-methyl-1-(3-(trifluoromethyl)benzyl)pyrrolidine-2-carboxylate (D17)
The title compound (D17) (37 mg) was prepared according to the general procedure for esters hydrolysis starting from (R)-methyl 2-methyl-1-(3-(trifluoromethyl)benzyl)pyrrolidine-2-carboxylate (D10) (47 mg). (LiOH: 2 eq; reaction time: 18 hrs).
MS: (ES/+) m/z: 288.3 [M-Li+2H + ] C14H15F3LiNO2 requires 293.21
Description 18: methyl 4-((1S)-1-(1-(3,4-difluorobenzyl)piperidine-2-carboxamido)ethyl)benzoate (diastereoisomer mixture) (D18)
The title compound (D18) (67 mg) was prepared according to the general procedure for substituted benzyl amines preparation starting from methyl 4-((1S)-1-(piperidine-2-carboxamido)ethyl) (D11) (50 mg, 0.17 mmol) and 3,4-difluorobenzyl bromide (0.044 ml, 0.34 mmol). (Na 2 CO 3 : 2.5 eq; reaction time: 4 hrs; 68° C.)
MS: (ES/+) m/z: 417 [MH + ] C23H26F2N2O3 requires 416.19
Chiral HPLC [Phenomenex Lux Cellulose-1; Mobile phase A: 90% n-hexane (+0.1% DEA) 10% EtOH; DAD: 237 nm]: Peak 1 retention time: 17.94 min; Peak 2 retention time: 19.03.
1 H NMR (400 MHz, CHCl3-d) δ (ppm): 8.05 (d, J=8.0 Hz, 2H), 7.89 (d, J=7.9 Hz, 2H), 7.39 (d, J=7.9 Hz, 2H), 7.20-7.10 (m, 2H), 7.03 (d, J=8.8 Hz, 2H), 7.00-6.73 (m, 4H), 5.26-5.12 (m, 2H), 3.93 (d, J=8.1 Hz, 6H), 3.86 (d, J=14.1 Hz, 1H), 3.59 (d, J=14.2 Hz, 1H), 3.21 (d, J=14.1 Hz, 1H), 3.07 (d, J=14.2 Hz, 1H), 2.87 (br. s., 4H), 2.00 (d, J=12.8 Hz, 4H), 1.83-1.70 (m, 2H), 1.68-1.57 (m, J=12.3 Hz, 6H), 1.55 (d, J=6.9 Hz, 3H), 1.46 (d, J=6.8 Hz, 3H), 1.39-1.31 (m, 2H).
Description 19: methyl 4-((1S)-1-(1-(3-methylbenzyl)piperidine-2-carboxamido)ethyl)benzoate (diastereoisomers mixture) (D19)
The title compound (D19) (63 mg) was prepared according to the general procedure for substituted benzyl amines preparation starting from methyl 4-((1S)-1-(piperidine-2-carboxamido)ethyl) (D11) (50 mg, 0.17 mmol) and 3-methyl benzyl bromide (0.046 ml, 0.34 mmol). (Na 2 CO 3 : 2.5 eq; reaction time: 3 hrs; 68° C.)
MS: (ES/+) m/z: 395.3 [MH + ] C24H30N2O3 requires 394.23
Description 20: methyl 4-((1S)-1-(1-(3-fluorobenzyl)piperidine-2-carboxamido)ethyl)benzoate (diastereoisomers mixture) (D20)
The title compound (D20) (54 mg) was prepared according to the general procedure for substituted benzyl amines preparation starting from methyl 4-((1S)-1-(piperidine-2-carboxamido)ethyl) (D11) (50 mg, 0.17 mmol) and 3-fluoro benzyl bromide (0.042 ml, 0.34 mmol). (Na 2 CO 3 : 2.5 eq; reaction time: 3 hrs; 68° C.)
MS: (ES/+) m/z: 399.3 [MH + ] C23H27FN2O3 requires 398.20
Description 21: methyl 4-((1S)-1-(1-(3-(trifluoromethyl)benzyl)piperidine-2-carboxamido)ethyl)benzoate (diastereoisomers mixture) (D21)
The title compound (D21) (45 mg) was prepared according to the general procedure for substituted benzyl amines preparation starting from methyl 4-((1S)-1-(piperidine-2-carboxamido)ethyl) (D11) (50 mg, 0.17 mmol) and 3-(trifluoromethyl)benzyl bromide (0.052 ml, 0.34 mmol). (Na 2 CO 3 : 2.5 eq; reaction time: 3 hrs; 68° C.)
MS: (ES/+) m/z: 449.3 [MH + ] C24H27F3N2O3 requires 448.20
1 H NMR (400 MHz, CHCl3-d) δ (ppm): 8.12-7.79 (m, 4H), 7.59 (d, J=13.4 Hz, 3H), 7.50 (br. s., 4H), 7.39 (d, J=8.2 Hz, 3H), 7.25 (d, J=8.0 Hz, 2H), 7.05 (d, J=7.9 Hz, 2H), 5.28-5.03 (m, 2H), 4.02-3.83 (m, 7H), 3.78-3.64 (m, J=14.3 Hz, 1H), 3.37-3.12 (m, 2H), 2.99-2.80 (m, 4H), 2.14-1.96 (m, 4H), 1.83-1.70 (m, J=13.0 Hz, 2H), 1.69-1.46 (m, 9H), 1.44 (d, J=6.9 Hz, 3H), 1.39-1.29 (m, 2H)
Description 22: methyl 4-((S)-1-((R)-1-(3-(trifluoromethyl)benzyl)piperidine-2-carboxamido)ethyl)benzoate (D22)
The title compound (D22) (18 mg) was prepared according to the general procedure for substituted benzyl amines preparation starting from methyl 4-((S)-1-((R)-piperidine-2-carboxamido)ethyl)benzoate (D12) (40 mg, 0.14 mmol) and 3-(trifluoromethyl)benzyl bromide (0.031 ml, 0.21 mmol). (Na 2 CO 3 : 2.5 eq; reaction time: 4 hrs; 60° C.)
MS: (ES/+) m/z: 449.3 [MH + ] C24H27F3N2O3 requires 448.20
1 H NMR (400 MHz, CHCl3-d) δ (ppm): 8.04 (d, J=8.0 Hz, 2H), 7.64-7.54 (m, 2H), 7.50 (br. s., 2H), 7.39 (d, J=8.0 Hz, 2H), 7.05 (d, J=7.9 Hz, 1H), 5.17 (t, J=7.2 Hz, 1H), 3.98 (d, J=1.0 Hz, 1H), 3.94 (s, 3H), 3.31 (d, J=14.2 Hz, 1H), 3.00-2.81 (m, 2H), 2.10-1.95 (m, 2H), 1.81-1.69 (m, 1H), 1.63 (d, J=12.7 Hz, 1H), 1.57-1.46 (m, 2H), 1.44 (d, J=6.9 Hz, 3H), 1.32 (d, J=12.3 Hz, 1H).
Description 23: methyl 4-((S)-1-((R)-1-(3-fluorobenzyl)piperidine-2-carboxamido)ethyl)benzoate (D23)
The title compound (D23) (40 mg) was prepared according to the general procedure for substituted benzyl amines preparation starting from methyl 4-((S)-1-((R)-piperidine-2-carboxamido)ethyl)benzoate (D12) (50 mg, 0.17 mmol) and 3-fluorobenzyl bromide (0.042 ml, 0.34 mmol). (Na 2 CO 3 : 2.5 eq; reaction time: 3 hrs; 60° C.)
MS: (ES/+) m/z: 399.3 [MH + ] C23H27FN2O3 requires 398.20
Description 24: methyl 4-((S)-1-((R)-1-(3-methylbenzyl)piperidine-2-carboxamido)ethyl)benzoate (D24)
The title compound (D24) (48 mg) was prepared according to the general procedure for substituted benzyl amines preparation starting from methyl 4-((S)-1-((R)-piperidine-2-carboxamido)ethyl)benzoate (D12) (50 mg, 0.17 mmol) and 3-methylbenzyl bromide (0.046 ml, 0.34 mmol). (Na 2 CO 3 : 2.5 eq; reaction time: 3 hrs; 60° C.)
MS: (ES/+) m/z: 395.3 [MH + ] C24H30N2O3 requires 394.23
Description 25: methyl 4-((S)-1-((R)-1-(3-(trifluoromethoxy)benzyl)piperidine-2-carboxamido)ethyl)benzoate (D25)
A mixture of methyl 4-((S)-1-((R)-piperidine-2-carboxamido)ethyl)benzoate (D12) (50 mg, 0.17 mmol) and 3-(trifluoromethoxy)benzaldehyde (0.025 ml, 0.20 mmol), NaBH(OAc) 3 (109 mg, 0.52 mmol) and catalytic CH 3 COOH in DCM (12 ml) was heated at 100° C. (2 cycles of 5 min each) under microwave irradiation. The resulting mixture was purified by SPE-Si (2 g) eluting with a mixture DCM/AcOEt from 100/0 to 80/20. Collected fractions after solvent evaporation afforded the title compound (D25) (52 mg).
MS: (ES/+) m/z: 395.3 [MH + ] C24H27F3N2O4 requires 464.19
Description 26: (R)-methyl 4-(1-(1-(3-(trifluoromethyl)benzyl)piperidine-2-carboxamido)cyclopropyl)benzoate (D26)
The title compound (D26) (76 mg) was prepared according to the general procedure for substituted benzyl amines preparation starting from (R)-methyl 4-(1-(piperidine-2-carboxamido)cyclopropyl)benzoate (D13) (50 mg, 0.16 mmol) and 3-(trifluoromethyl)benzyl bromide (0.038 ml, 0.25 mmol). (Na 2 CO 3 : 2.5 eq; reaction time: 6 hrs; 60° C.)
MS: (ES/+) m/z: 461.3 [MH + ] C25H27F3N2O3 requires 460.20
Description 27: (R)-methyl 4-(1-(1-(3-methylbenzyl)piperidine-2-carboxamido)cyclopropyl)benzoate (D27)
The title compound (D27) (63 mg) was prepared according to the general procedure for substituted benzyl amines preparation starting from (R)-methyl 4-(1-(piperidine-2-carboxamido)cyclopropyl)benzoate (D13) (50 mg, 0.16 mmol) and 3-methyl benzyl bromide (0.033 ml, 0.25 mmol). (Na 2 CO 3 : 2.5 eq; reaction time: 6 hrs; 60° C.)
MS: (ES/+) m/z: 407.3 [MH + ] C25H30N2O3 requires 406.23
Description 28: (R)-methyl 4-(1-(1-(3-fluorobenzyl)piperidine-2-carboxamido)cyclopropyl)benzoate (D28)
The title compound (D28) (62 mg) was prepared according to the general procedure for substituted benzyl amines preparation starting from (R)-methyl 4-(1-(piperidine-2-carboxamido)cyclopropyl)benzoate (D13) (50 mg, 0.16 mmol) and 3-fluoro benzyl bromide (0.03 ml, 0.25 mmol). (Na 2 CO 3 : 2.5 eq; reaction time: 6 hrs; 60° C.)
MS: (ES/+) m/z: 411.3 [MH + ] C24H27FN2O3 requires 410.20
Description 29: (R)-methyl 4-(1-(1-(4-fluoro-3-methylbenzyl)piperidine-2-carboxamido)cyclopropyl)benzoate (D29)
A mixture of (R)-methyl 4-(1-(piperidine-2-carboxamido)cyclopropyl)benzoate (D13) (40 mg, 0.13 mmol) and 4-fluoro-3-methyl benzaldehyde (0.02 ml, 0.16 mmol), NaBH(OAc) 3 (84 mg, 0.4 mmol) and CH 3 COOH (0.076 ml, 1.3 mmol) in DCM (10 ml) was heated at 110° C. (2 cycles of 5 min each) under microwave irradiation. The resulting mixture was purified by SPE-Si (2 g) eluting with a mixture DCM/AcOEt from 100/0 to 80/20. Collected fractions after solvent evaporation afforded the title compound (D29) (33 mg).
MS: (ES/+) m/z: 425.3 [MH + ] C25H29FN2O3 requires 424.22
Description 30: (R)-methyl 4-(1-(1-(4-fluoro-3-(trifluoromethyl)benzyl)piperidine-2-carboxamido)cyclopropyl)benzoate (D30)
The title compound (D30) (35 mg) was prepared according sperimental procedure described in description 29 starting from (R)-methyl 4-(1-(piperidine-2-carboxamido)cyclopropyl)benzoate (D13) (40 mg, 0.13 mmol) and 4-fluoro-3-(trifluoromethyl)benzaldehyde (0.02 ml, 0.16 mmol)
MS: (ES/+) m/z: 479.3 [MH + ] C25H26F4N2O3 requires 478.19
Description 31: methyl 4-((S)-1-((R)-1-(3-fluorobenzyl)pyrrolidine-2-carboxamido)ethyl)benzoate (D31)
The title compound (D31) (55 mg) was prepared according to the general procedure for substituted benzyl amines preparation starting from methyl 4-((S)-1-((R)-pyrrolidine-2-carboxamido)ethyl)benzoate (D14) (50 mg, 0.18 mmol) and 3-fluoro benzyl bromide (0.044 ml, 0.36 mmol). (Na 2 CO 3 : 2.5 eq; reaction time: 5 hrs; 70° C.)
MS: (ES/+) m/z: 385.6 [MH + ] C22H25FN2O3 requires 384.18
Description 32: methyl 4-((S)-1-((R)-1-(3-(trifluoromethyl)benzyl)pyrrolidine-2-carboxamido)ethyl)benzoate (D32)
The title compound (D32) (70 mg) was prepared according to the general procedure for substituted benzyl amines preparation starting from methyl 4-((S)-1-((R)-pyrrolidine-2-carboxamido)ethyl)benzoate (D14) (50 mg, 0.18 mmol) and 3-(trifluoromethyl)benzyl bromide (0.055 ml, 0.36 mmol). (Na 2 CO 3 : 2.5 eq; reaction time: 5 hrs; 70° C.)
MS: (ES/+) m/z: 434.9 [MH + ] C23H25F3N2O3 requires 434.18
Description 33: methyl 4-((S)-1-((R)-1-(3-methylbenzyl)pyrrolidine-2-carboxamido)ethyl)benzoate (D33)
The title compound (D33) (30 mg) was prepared according to the general procedure for substituted benzyl amines preparation starting from methyl 4-((S)-1-((R)-pyrrolidine-2-carboxamido)ethyl)benzoate (D14) (50 mg, 0.18 mmol) and 3-methylbenzyl bromide (0.05 ml, 0.36 mmol). (Na 2 CO 3 : 2.5 eq; reaction time: 5 hrs; 70° C.)
MS: (ES/+) m/z: 381.6 [MH + ] C23H28N2O3 requires 380.21
Description 34: methyl 4-((S)-1-((R)-1-(3,4-difluorobenzyl)pyrrolidine-2-carboxamido)ethyl)benzoate (D34)
The title compound (D34) (39 mg) was prepared according to the general procedure for substituted benzyl amines preparation starting from methyl 4-((S)-1-((R)-pyrrolidine-2-carboxamido)ethyl)benzoate (D14) (50 mg, 0.18 mmol) and 3,4-difluorobenzyl bromide (0.046 ml, 0.36 mmol). (Na 2 CO 3 : 2.5 eq; reaction time: 5 hrs; 70° C.)
MS: (ES/+) m/z: 403.6 [MH + ] C22H24F2N2O3 requires 402.18
Description 35: methyl 4-((S)-1-((2R,4R)-4-hydroxy-1-(3-(trifluoromethyl)benzyl)pyrrolidine-2-carboxamido)ethyl)benzoate (D35)
The title compound (D35) (10.3 mg) was prepared according to the general procedure for amides preparation starting from lithium (2R,4R)-4-hydroxy-1-(3-(trifluoromethyl)benzyl)pyrrolidine-2-carboxylate (D15) (11.7 mg, 0.054 mmol) and methyl 4-(1-aminocyclopropyl)benzoate hydrochloride (27.2 mg, 0.054 mmol).
MS: (ES/+) m/z: 451.2 [MH + ] C23H25F3N2O4 requires 450.18
1 H NMR (400 MHz, CHCl3-d) δ (ppm): 8.02 (d, J=8.0 Hz, 2H), 7.64-7.55 (m, 2H), 7.50 (d, J=3.9 Hz, 3H), 7.33 (d, J=8.0 Hz, 2H), 5.14-5.00 (m, J=7.1, 7.1 Hz, 1H), 4.40 (br. s., 1H), 4.01 (d, J=13.3 Hz, 1H), 3.93 (s, 3H), 3.79 (d, J=13.1 Hz, 1H), 3.65 (br. s., 1H), 3.31 (d, J=6.1 Hz, 1H), 2.58 (d, J=8.2 Hz, 1H), 2.37-2.20 (m, 1H), 2.10-1.92 (m, 2H), 1.41 (d, J=6.8 Hz, 3H).
Description 36: methyl 4-((S)-1-((2R,4S)-4-fluoro-1-(3-(trifluoromethyl)benzyl)pyrrolidine-2-carboxamido)ethyl)benzoate (D36)
The title compound (D36) (67.3 mg) was prepared according to the general procedure for amides preparation starting from lithium (2R,4S)-4-fluoro-1-(3-(trifluoromethyl)benzyl)pyrrolidine-2-carboxylate (D16) (60 mg) and (S)-methyl 4-(1-aminoethyl)benzoate hydrochloride (43.5 mg).
MS: (ES/+) m/z: 475.2 [MH+Na + ]C23H24F4N2O3 requires 452.17
1 H NMR (400 MHz, CHCl3-d) δ (ppm): 8.01 (d, J=8.1 Hz, 2H), 7.75-7.46 (m, 5H), 7.36 (d, J=8.1 Hz, 2H), 5.32-5.00 (m, 2H), 4.01 (d, J=13.2 Hz, 1H), 3.92 (s, 3H), 3.70 (d, J=13.2 Hz, 1H), 3.54-3.33 (m, 2H), 2.73-2.41 (m, 2H), 2.31-2.11 (m, 1H), 1.42 (d, J=6.8 Hz, 3H)
Description 37: methyl 4-((S)-1-((R)-2-methyl-1-(3-(trifluoromethyl)benzyl)pyrrolidine-2-carboxamido)ethyl)benzoate (D37)
The title compound (D37) (30.9 mg) was prepared according to the general procedure for amides preparation starting from lithium (R)-2-methyl-1-(3-(trifluoromethyl)benzyl)pyrrolidine-2-carboxylate (D17) (37 mg, 0.13 mmol) and methyl 4-(1-aminocyclopropyl)benzoate hydrochloride (27.2 mg, 0.13 mmol).
MS: (ES/+) m/z: 449.3 [MH + ] C24H27F3N2O3 requires 448.20
1 H NMR (400 MHz, CHCl3-d) δ (ppm): 8.02 (d, J=8.0 Hz, 2H), 7.99 (br. s., 1H), 7.64-7.55 (m, 2H), 7.50 (d, J=4.1 Hz, 2H), 7.37 (d, J=7.9 Hz, 2H), 5.19-5.06 (m, J=7.2, 7.2 Hz, 1H), 3.93 (s, 4H), 3.46 (d, J=13.1 Hz, 1H), 3.07-2.93 (m, 1H), 2.46 (d, J=6.8 Hz, 1H), 2.09-1.95 (m, 1H), 1.85-1.77 (m, 2H), 1.75-1.65 (m, 1H), 1.51 (d, J=6.9 Hz, 3H), 1.37 (br. s., 3H).
EXAMPLES
Example 1
lithium 4-((1S)-1-(1-(3,4-difluorobenzyl)piperidine-2-carboxamido) ethyl)benzoate (E1)
The title compound (E1) (62 mg) was prepared according to the general procedure for esters hydrolysis starting from methyl 4-((1S)-1-(1-(3,4-difluorobenzyl)piperidine-2-carboxamido)ethyl)benzoate (D18) (67 mg). (LiOH H 2 O: 1.75 eq; reaction time: 3 hrs)
MS: (ES/+) m/z: 403 [M-Li+2H + ] C22H23F2LiN2O3 requires 408.18
1 H NMR (400 MHz, MeOH-d4) δ (ppm): 7.92 (d, J=7.9 Hz, 1H), 7.87 (d, J=7.9 Hz, 1H), 7.36 (d, J=8.0 Hz, 1H), 7.34-7.22 (m, J=8.0 Hz, 2H), 7.22-6.98 (m, 2H), 5.19-5.04 (m, 1H), 3.70 (t, J=1.0 Hz, 1H), 3.41-3.35 (m, 1H), 3.10 (t, J=1.0 Hz, 1H), 2.90-2.76 (m, 2H), 2.04-1.92 (m, 1H), 1.90-1.65 (m, 3H), 1.64-1.58 (m, 1H), 1.49 (dd, J=6.9, 18.5 Hz, 3H), 1.40-1.26 (m, 1H)
Example 2
lithium 4-((1S)-1-(1-(3-methylbenzyl)piperidine-2-carboxamido) ethyl)benzoate (E2)
The title compound E2 (60 mg) was prepared according to the general procedure for esters hydrolysis starting from methyl 4-((1S)-1-(1-(3-methylbenzyl)piperidine-2-carboxamido)ethyl)benzoate (D19) (42 mg). (LiOH H 2 O: 1.75 eq; reaction time: 3 hrs)
MS: (ES/+) m/z: 381.3 [M-Li+2H + ] C23H27LiN2O3 requires 386.22
Example 3
lithium 4-((1S)-1-(1-(3-fluorobenzyl)piperidine-2-carboxamido) ethyl)benzoate (E3)
The title compound (E3) (50 mg) was prepared according to the general procedure for esters hydrolysis starting from methyl 4-((1S)-1-(1-(3-fluorobenzyl)piperidine-2-carboxamido)ethyl)benzoate (D20) (54 mg). (LiOH H 2 O: 1.75 eq; reaction time: 3 hrs)
MS: (ES/+) m/z: 385.3 [M-Li+2H + ] C22H24FLiN2O3 requires 390.19
Example 4
lithium 4-((1S)-1-(1-(3-(trifluoromethyl)benzyl)piperidine-2-carboxamido)ethyl)benzoate (E4)
The title compound (E4) (20 mg) was prepared according to the general procedure for esters hydrolysis starting from methyl 4-((1S)-1-(1-(3-(trifluoromethyl)benzyl)piperidine-2-carboxamido)ethyl)benzoate (D21) (45 mg). (LiOH H 2 O: 1.75 eq; reaction time: 3 hrs)
MS: (ES/+) m/z: 435.3 [M-Li+2H + ] C23H24F3LiN2O 3 requires 440.19
1 H NMR (400 MHz, MeOH-d4) δ (ppm): 7.97-7.82 (m, 2H), 7.74-7.63 (m, 1H), 7.63-7.46 (m, 3H), 7.39-7.28 (m, 2H), 5.16-5.07 (m, 1H), 3.88-3.75 (m, 1H), 3.27-3.12 (m, 2H), 2.91-2.79 (m, 2H), 2.07-1.93 (m, 1H), 1.91-1.65 (m, 3H), 1.64-1.58 (m, 1H), 1.53-1.44 (m, 3H), 1.42-1.29 (m, 1H).
Example 5
lithium 4-((S)-1-((R)-1-(3-(trifluoromethyl)benzyl)piperidine-2-carboxamido)ethyl)benzoate (E5)
The title compound (E5) (5.02 mg) was prepared according to the general procedure for esters hydrolysis starting from methyl 4-((S)-1-((R)-1-(3-(trifluoromethyl)benzyl)piperidine-2-carboxamido)ethyl)benzoate (D22) (19 mg). (LiOH H 2 O: 1.75 eq; reaction time: 3 hrs)
MS: (ES/+) m/z: 435.2 [M-Li+2H + ] C23H24F3LiN2O3 requires 440.19
1 H NMR (400 MHz, MeOH-d4) δ (ppm): 7.93 (d, J=7.9 Hz, 2H), 7.61 (d, J=1.0 Hz, 2H), 7.54 (d, J=1.0 Hz, 2H), 7.36 (d, J=7.9 Hz, 2H), 5.16-5.03 (m, 1H), 3.88-3.80 (m, 1H), 3.27 (d, J=1.0 Hz, 1H), 2.86 (d, J=10.3 Hz, 2H), 2.07-1.96 (m, 1H), 1.93-1.65 (m, 3H), 1.65-1.51 (m, 2H), 1.46 (d, J=6.9 Hz, 3H), 1.41-1.27 (m, 1H).
Example 6
lithium 4-((S)-1-((R)-1-(3-fluorobenzyl)piperidine-2-carboxamido)ethyl)benzoate (E6)
The title compound (E6) (36 mg) was prepared according to the general procedure for esters hydrolysis starting from methyl 4-((S)-1-((R)-1-(3-fluorobenzyl)piperidine-2-carboxamido)ethyl)benzoate (D23 (40 mg). (LiOH H 2 O: 3 eq; reaction time: 3 hrs)
MS: (ES/+) m/z: 385.3 [M-Li+2H + ] C22H24FLiN2O3 requires 390.19
Chiral HPLC [Daicel OD-H; Mobile phase A: 60% n-hexane (+0.2% TFA), 40% EtOH; DAD: 235 nm]: Peak retention time: 5.7 min.
1 H NMR (400 MHz, MeOH-d4) δ (ppm): 7.93 (d, J=7.9 Hz, 2H), 7.41-7.26 (m, 3H), 7.20-6.92 (m, 3H), 5.09 (d, J=6.9 Hz, 1H), 3.78 (d, J=13.4 Hz, 1H), 3.18 (d, J=13.4 Hz, 1H), 2.86 (dd, J=11.3, 17.0 Hz, 2H), 2.07-1.94 (m, J=2.8 Hz, 1H), 1.91-1.64 (m, 3H), 1.63-1.53 (m, 2H), 1.47 (d, J=6.9 Hz, 3H), 1.41-1.26 (m, J=11.6 Hz, 1H).
Example 7
lithium 4-((S)-1-((R)-1-(3-methylbenzyl)piperidine-2-carboxamido) ethyl)benzoate (E7)
The title compound (E7) (28 mg) was prepared according to the general procedure for esters hydrolysis starting from methyl 4-((S)-1-((R)-1-(3-methylbenzyl)piperidine-2-carboxamido)ethyl)benzoate (D24) (48 mg). (LiOH H 2 O: 3 eq; reaction time: 3 hrs)
MS: (ES/+) m/z: 381.3 [M-Li+2H + ] C23H27LiN2O3 requires 386.22
Chiral HPLC [Daicel IC; Mobile phase A: 70% n-hexane (+0.2% TFA), 30% EtOH; DAD: 235 nm]: Peak retention time: 6.6 min.
Example 8
lithium 4-((S)-1-((R)-1-(3-(trifluoromethoxy)benzyl)piperidine-2-carboxamido)ethyl)benzoate (E8)
The title compound (E8) (51 mg) was prepared according to the general procedure for esters hydrolysis starting from methyl 4-((S)-1-((R)-1-(3-(trifluoromethoxy)benzyl)piperidine-2-carboxamido)ethyl)benzoate (D25) (52 mg). (LiOH H 2 O: 3 eq; reaction time: 3 hrs)
MS: (ES/+) m/z: 451.3 [M-Li+2H + ] C23H24F3LiN2O 4 requires 456.18
Chiral HPLC [Daicel OD-H; Mobile phase A: 60% n-hexane (+0.2% TFA), 40% IPA; DAD: 235 nm]: Peak retention time: 5.7 min.
Example 9
lithium (R)-4-(1-(1-(3-(trifluoromethyl)benzyl)piperidine-2-carboxamido)cyclopropyl)benzoate (E9)
The title compound (E9) (51 mg) was prepared according to the general procedure for esters hydrolysis starting from (R)-methyl 4-(1-(1-(3-(trifluoromethyl)benzyl)piperidine-2-carboxamido)cyclopropyl)benzoate (D26) (76 mg). (LiOH H 2 O: 3 eq; reaction time: 3 hrs)
MS: (ES/+) m/z: 447.2 [M-Li+2H + ] C24H24F3LiN2O3 requires 452.19
Chiral HPLC [Daicel OD-H; Mobile phase A: 90% n-hexane (+0.1% TFA), 10% IPA; DAD: 225 nm]: Peak retention time: 26.9 min.
1 H NMR (400 MHz, MeOH-d4) δ (ppm): 7.86 (d, J=1.0 Hz, 2H), 7.71 (s, 1H), 7.67-7.61 (m, 1H), 7.60-7.55 (m, 1H), 7.55-7.48 (m, 1H), 7.23 (d, J=1.0 Hz, 2H), 3.81 (d, J=1.0 Hz, 1H), 3.26-3.19 (m, 2H), 2.90-2.79 (m, 2H), 2.06-1.97 (m, 1H), 1.96-1.89 (m, 1H), 1.85-1.75 (m, 2H), 1.64-1.53 (m, 2H), 1.43-1.26 (m, 4H).
Example 10
lithium (R)-4-(1-(1-(3-methylbenzyl)piperidine-2-carboxamido)cyclopropyl)benzoate (E10)
The title compound (E10) (61 mg) was prepared according to the general procedure for esters hydrolysis starting from (R)-methyl 4-(1-(1-(3-methylbenzyl)piperidine-2-carboxamido)cyclopropyl)benzoate (D27) (63 mg). (LiOH H 2 O: 3 eq; reaction time: 3 hrs)
MS: (ES/+) m/z: 393.2 [M-Li+2H + ] C24H27LiN2O3 requires 398.22
1 H NMR (400 MHz, MeOH-d4) δ (ppm): 7.86 (d, J=8.0 Hz, 2H), 7.32-7.03 (m, 6H), 3.74 (d, J=13.1 Hz, 1H), 3.38-3.30 (1H, 1H, under residual solvent), 3.12 (d, J=13.1 Hz, 1H), 2.90 (d, J=11.5 Hz, 1H), 2.79 (d, J=10.2 Hz, 1H), 2.34 (s, 3H), 2.02-1.87 (m, 2H), 1.84-1.67 (m, 2H), 1.66-1.48 (m, 2H), 1.44-1.26 (m, 4H).
Example 11
lithium (R)-4-(1-(1-(3-fluorobenzyl)piperidine-2-carboxamido)cyclopropyl)benzoate (E11)
The title compound (E11) (61 mg) was prepared according to the general procedure for esters hydrolysis starting from (R)-methyl 4-(1-(1-(3-fluorobenzyl)piperidine-2-carboxamido)cyclopropyl)benzoate (D28) (62 mg). (LiOH H 2 O: 3 eq; reaction time: 3 hrs)
MS: (ES/+) m/z: 397.2 [M-Li+2H + ] C23H24FLiN2O3 requires 402.19
Example 12
(R)-4-(1-(1-(4-fluoro-3-methylbenzyl)piperidine-2-carboxamido)cyclopropyl)benzoic acid (E12)
The title compound (E12) (10.1 mg) was prepared according to the general procedure for esters hydrolysis starting from (R)-methyl 4-(1-(1-(4-fluoro-3-methylbenzyl)piperidine-2-carboxamido)cyclopropyl)benzoate (D29) (33 mg). (LiOH H 2 O: 3 eq; reaction time: 3 hrs)
MS: (ES/+) m/z: 411.2 [MH + ] C24H27FN2O3 requires 410.20
1 H NMR (400 MHz, MeOH-d4) δ (ppm): 7.90 (d, J=7.8 Hz, 2H), 7.29 (d, J=7.8 Hz, 2H), 7.24 (d, J=7.0 Hz, 1H), 7.17 (br. s., 1H), 6.98 (s, 1H), 3.76 (d, J=13.1 Hz, 1H), 3.39-3.36 (1H, under residual solvent), 3.20 (d, J=13.1 Hz, 1H), 3.02-2.86 (m, 2H), 2.27 (s, 3H), 2.17-2.03 (m, 1H), 1.97-1.91 (m, 1H), 1.79 (d, J=8.6 Hz, 2H), 1.68-1.49 (m, 2H), 1.44-1.29 (m, 4H)
Example 13
lithium (R)-4-(1-(1-(4-fluoro-3-(trifluoromethyl)benzyl)piperidine-2-carboxamido)cyclopropyl)benzoate (E13)
The title compound (E13) (11.1 mg) was prepared according to the general procedure for esters hydrolysis starting from (R)-methyl 4-(1-(1-(4-fluoro-3-(trifluoromethyl)benzyl)piperidine-2-carboxamido)cyclopropyl)benzoate (D30) (35 mg). (LiOH H 2 O: 3 eq; reaction time: 3 hrs)
MS: (ES/+) m/z: 465.2 [M-Li+2H + ] C24H23F4LiN2O3 requires 470.18
Example 14
lithium 4-((S)-1-((R)-1-(3-fluorobenzyl)pyrrolidine-2-carboxamido)ethyl)benzoate (E14)
The title compound (E14) (48 mg) was prepared according to the general procedure for esters hydrolysis starting from methyl 4-((S)-1-((R)-1-(3-fluorobenzyl)pyrrolidine-2-carboxamido)ethyl)benzoate (D31) (53 mg). (LiOH H 2 O: 1.5 eq; reaction time: 24 hrs)
MS: (ES/+) m/z: 371.5 [M-Li+2H + ] C24H23F4LiN2O3 requires 376.18
Example 15
lithium 4-((S)-1-((R)-1-(3-(trifluoromethyl)benzyl)pyrrolidine-2-carboxamido)ethyl)benzoate (E15)
The title compound (E15) (57 mg) was prepared according to the general procedure for esters hydrolysis starting from methyl 4-((S)-1-((R)-1-(3-(trifluoromethyl)benzyl)pyrrolidine-2-carboxamido)ethyl)benzoate (D32) (69 mg). (LiOH H 2 O: 1.5 eq; reaction time: 24 hrs)
MS: (ES/+) m/z: 421.6 [M-Li+2H + ] C22H22F3LiN2O3 requires 426.17
Chiral HPLC [Daicel OD-H; Mobile phase A: 90% n-hexane (+0.5% TFA), 10% EtOH; DAD: 235 nm]: Peak retention time: 12.5 min.
1 H NMR (400 MHz, MeOH-d4) δ (ppm): 7.92 (d, J=7.9 Hz, 2H), 7.70 (s, 1H), 7.67-7.51 (m, 3H), 7.28 (d, J=7.9 Hz, 2H), 4.98-4.89 (m, 1H), 3.88 (d, J=1.0 Hz, 1H), 3.75 (d, J=1.0 Hz, 1H), 3.27-3.19 (m, 1H), 3.19-3.09 (m, 1H), 2.56-2.45 (m, 1H), 2.30-2.12 (m, 1H), 1.82 (br. s., 3H), 1.36 (d, J=6.9 Hz, 3H).
Example 16
lithium 4-((S)-1-((R)-1-(3-methylbenzyl)pyrrolidine-2-carboxamido)ethyl)benzoate (E16)
The title compound (E16) (24 mg) was prepared according to the general procedure for esters hydrolysis starting from methyl 4-((S)-1-((R)-1-(3-methylbenzyl)pyrrolidine-2-carboxamido)ethyl)benzoate (D33) (29 mg). (LiOH H 2 O: 1.5 eq; reaction time: 24 hrs)
MS: (ES/+) m/z: 367.6 [M-Li+2H + ] C22H25LiN2O3 requires 372.20
Example 17
lithium 4-((S)-1-((R)-1-(3,4-difluorobenzyl)pyrrolidine-2-carboxamido)ethyl)benzoate (E17)
The title compound (E17) (36 mg) was prepared according to the general procedure for esters hydrolysis starting from methyl 4-((S)-1-((R)-1-(3,4-difluorobenzyl)pyrrolidine-2-carboxamido)ethyl)benzoate (D34) (38 mg). (LiOH H 2 O: 1.5 eq; reaction time: 24 hrs)
MS: (ES/+) m/z: 389.6 [M-Li+2H + ] C21H21F2LiN2O3 requires 394.17
Chiral HPLC [Daicel OD-H; Mobile phase A: 90% n-hexane (+0.5% TFA), 10% EtOH; DAD: 237 nm]: Peak retention time: 15.7 min.
1 H NMR (400 MHz, MeOH-d4) δ (ppm): 7.93 (d, J=7.9 Hz, 2H), 7.30 (d, J=7.8 Hz, 3H), 7.26-7.07 (m, 2H), 5.03-4.89 (m, 1H), 3.74 (s, 1H), 3.67 (s, 1H), 3.24-3.09 (m, 2H), 2.56-2.41 (m, 1H), 2.30-2.10 (m, 1H), 1.86-1.71 (m, J=2.5 Hz, 3H), 1.40 (d, J=6.9 Hz, 3H)
Example 18
lithium 4-((S)-1-((R)-2-methyl-1-(3-(trifluoromethyl)benzyl)pyrrolidine-2-carboxamido)ethyl)benzoate (E18)
The title compound (E18) (9 mg) was prepared according to the general procedure for esters hydrolysis starting from methyl 4-((S)-1-((R)-2-methyl-1-(3-(trifluoromethyl)benzyl)pyrrolidine-2-carboxamido)ethyl)benzoate (D35) (68.6 mg). (LiOH H 2 O: 2 eq; reaction time: 18 hrs)
MS: (ES/+) m/z: 435.3 [M-Li+2H + ] C23H24F3LiN2O3 requires 440.19
1 H NMR (400 MHz, MeOH-d4) δ (ppm): 7.94 (d, J=7.9 Hz, 2H), 7.71-7.64 (m, 2H), 7.63-7.55 (m, 2H), 7.31 (d, J=7.9 Hz, 2H), 5.06-4.97 (m, J=6.9 Hz, 1H), 3.96 (d, J=13.5 Hz, 1H), 3.56 (d, J=13.5 Hz, 1H), 3.05-2.96 (m, 1H), 2.58-2.49 (m, J=7.9 Hz, 1H), 2.12-2.00 (m, 1H), 1.88-1.71 (m, 3H), 1.49 (d, J=6.9 Hz, 3H), 1.36 (s, 3H).
Example 19
lithium 4-((S)-1-((2R,4R)-4-hydroxy-1-(3-(trifluoromethyl)benzyl)pyrrolidine-2-carboxamido)ethyl)benzoate (E19)
The title compound (E19) (9 mg) was prepared according to the general procedure for esters hydrolysis starting from methyl 4-((S)-1-((2R,4R)-4-hydroxy-1-(3-(trifluoromethyl)benzyl)pyrrolidine-2-carboxamido)ethyl)benzoate (D36) (10.3 mg). (LiOH H 2 O: 2 eq; reaction time: 18 hrs)
MS: (ES/+) m/z: 437.3 [M-Li+2H + ] C22H22F3LiN2O 4 requires 442.17
1 H NMR (400 MHz, MeOH-d4) δ (ppm): 7.92 (d, J=7.9 Hz, 2H), 7.70 (br. s., 1H), 7.61 (br. s., 2H), 7.56-7.50 (m, 1H), 7.29 (d, J=7.9 Hz, 2H), 4.99-4.92 (m, 1H), 4.40-4.27 (m, 1H), 3.94 (d, J=1.0 Hz, 1H), 3.78 (d, J=1.0 Hz, 1H), 3.50 (t, J=1.0 Hz, 1H), 3.31-3.26 (m, 1H), 2.49 (t, J=1.0 Hz, 1H), 2.20-2.08 (m, 1H), 2.04-1.94 (m, 1H), 1.38 (d, J=6.9 Hz, 3H).
Example 20
lithium 4-((S)-1-((2R,4S)-4-fluoro-1-(3-(trifluoromethyl)benzyl)pyrrolidine-2-carboxamido)ethyl)benzoate (E20)
The title compound (E20) (50 mg) was prepared according to the general procedure for esters hydrolysis starting from methyl 4-((S)-1-((2R,4S)-4-fluoro-1-(3-(trifluoromethyl)benzyl)pyrrolidine-2-carboxamido)ethyl)benzoate (D37) (67.3 mg). (LiOH H 2 O: 2 eq; reaction time: 18 hrs)
MS: (ES/+) m/z: 439.2 [M-Li+2H + ] C22H21F4LiN2O3 requires 444.16
1 H NMR (400 MHz, MeOH-d4) δ (ppm): 7.90 (d, J=7.9 Hz, 2H), 7.71 (s, 1H), 7.69-7.54 (m, 3H), 7.27 (d, J=7.9 Hz, 2H), 5.28-5.05 (m, 1H), 4.92-4.90 (m, 1H), 3.92 (d, J=1.0 Hz, 1H), 3.83 (d, J=1.0 Hz, 1H), 3.38 (br. s., 2H), 2.83-2.48 (m, 2H), 2.17-1.97 (m, 1H), 1.34 (d, J=6.9 Hz, 3H).
Example 21
Determination of In Vitro Effects of the Invention Compounds
Stable Expression of Human EP 4 Receptors in the Human Embryonic Kidney (HEK293) Cell Line
The cDNA clone of human EP 4 receptor (NM — 000958.2) was obtained from Invitrogen™: Ultimate™ ORF Clone Collection-Clone ID IOH46525. The coding sequence was subcloned in expression vector pcDNATM6.2/V5-DEST by Gateway technology (Invitrogen™).
Human embryonic kidney cells (HEK-293) were stably transfected with expression vector for human EP 4 receptor in according to the method described in FuGENE®6 Transfection Reagent's manual (Roche Applied Science®).
Preparation of Membrane Fraction:
The EP 4 transfected cells were grown in Dulbecco's modified Eagle's medium containing 10% fetal bovine serum and 10 μg/ml Blasticidin S HCl (selection medium) at 37° C. in a humidified atmosphere of 5% CO2 in air.
For the membrane preparation, cells in flask were harvested by hypotonical/mechanical lysis with chilled (4° C.) TE buffer (5 mM TRIS, 5 mM etylenediamine tetra-acetic acid (EDTA), pH 7.4).
Cells were detached and lysed with 10 ml of hypotonic lysis buffer and by scraping. The cell lysate was vortexed for 30 sec and centrifuged at 40000×g at 4° C. for 22 min.
a) Membrane Binding Assay[3H]-Prostaglandin E2
The membrane pellet was resuspended in the same buffer (5 mM TRIS, 5 mM ethylenediamine tetra-acetic acid (EDTA), pH 7.4), and protein concentration was determined by Bradford method (Bio-Bad® assay).
This membrane preparation was stored at −80° C. freezer until use for binding assay.
([ 3 H]-PGE 2 ) membranes binding assays toward hEP 4 receptors (human EP 4 /HEK293 transfectant, see above) and hEP 2 receptors (human EP 2 /HEK293 transfectant, purchased from PerkinElmer Inc) were performed in 10 mM MES-KOH buffer pH6, containing 10 mM MgCl 2 and 1 mM CaCl 2 for EP 4 binding assay or 50 mM Tris-Cl, BSA 0.5% for EP 2 binding assay (according to supplier indication).
Ten microgram of protein from membrane fractions were incubated in a total volume of 0.1 ml (EP 4 ) or 0.2 ml (EP 2 ) with 1 nM (EP 4 ) or 3 nM (EP 2 ) [ 3 H]-PGE 2 (PerkinElmer Inc, 171 Ci/mmol). In both assays to determine the total binding or non specific binding, 1% DMSO or 1 μM prostaglandin E 2 (EP 4 ) or 100 μM (EP 2 ) were added to reaction mixtures, respectively. Incubation was conducted in a polypropylene 96 multiwell for 90 min (EP 4 ) or 60 min (EP 2 ) at room temperature prior to separation of the bound and free radioligand by vacuum manifold rapid filtration on glass fiber filters (Unifilter GFB96, PerkinElmer Inc) pre-soaked in 0.3% polyethyleneimine. Filters were washed with ice cold buffer pH 7.4 (50 mM HEPES, NaCl 500 mM, BSA 0.1% for EP 4 binding assay or 50 mM Tris-Cl for EP 2 binding assays) and the residual [ 3 H]-PGE 2 binding determined by solid scintillation counter (TopCount, PerkinElmer Inc).
In standard competition experiments the compounds were tested in a concentration range from 1 nM to 1 μM, and IC 50 determined. The affinity (Ki) of each compound was calculated according to the Cheng-Prousoff equation: Ki=IC50/(1+([C]/Kd)). Results were expressed as pKi (−log 10 Ki (M)
Compounds of example 1 to 20 were tested according to method of example 21a in a final concentration range range from 1 nM to 1 μM. All compounds showed good to excellent EP 4 affinities having pKi values from 6.3 to 8.4 at EP 4 receptor.
b) cAMP Assay on Human EP 4 Membrane of Transfected Cells.
The assay is based on the competition between endogenous cAMP and exogenously added biotinylated cAMP. The capture of cAMP is achieved by using a specific antibody conjugated to Donor beads.
Cell membranes prepared as described above, were resuspended in 1 ml stimulation buffer (HBSS 1×+BSA 0.1%+IBMX 0.5 mM+HEPES 5 mM+MgCl 2 10 mM+GTP 1 nM+GDP 10 μM+ATP 100 μM-pH 7.4). Cell membranes were dispensed into white 384-well microplates at final concentration of 1 μg/well and used for the determination of cAMP with the alphascreen cAMP functional assay (EnVision-PerkinElmer). Cell membrane/anti-cAMP Acceptor beads mix (5 μl) and a mixture of analysed compounds (dissolved in 100% DMSO to a final maximal concentration of 0.01% DMSO)/PGE 2 (5 μl) were incubated at room temperature (22-23° C.) for 30 min in the dark. The Biotinylated-cAMP and donor beads (15 μl) were dispensed into each well to start the competition reaction. After 1 h incubation RT (22-23° C.) in the dark the plate was read using EnVision platform to determine the cAMP level (excitation: 680 nm; emission:520,620 nm).
In each experiment:
cAMP standard curve (concentration range from 1×10-6 to 1×10-11 M in log intervals) with a negative control (no cAMP)
a positive control:forskolin 10 μM
Antagonism studies were performed stimulating HEK293 cell membrane with PGE 2 3 nM. The AlphaScreen signal is plotted as a function of log concentration of cAMP and EC50 is determined. EC50 value is calculated by linear regression.
Some compounds were tested according to method of example 21b. All compounds showed good to excellent EP 4 antagonism having EC50 values from 300 nM to 0.1 nM at EP 4 receptor.
The results of membrane binding assay and cAMP assay on human EP 4 membrane of transfected cells selection of preferred compounds are summarised in table 1.
TABLE 1
Example
Binding pKi
EC50 (nM)
E5
7.5
1.0
E9
8.1
2.9
E12
7.5
6.0
E13
8
8.0
E15
7.7
13.5
E19
7.4
0.1 | There is described a group of novel cyclic amine derivative compounds having an EP 4 receptor agonistic activity.
Specifically, the compounds according to the invention are provided with analgesic, antinflammatory, antiglaucoma activity, and also with anti-osteoporosis and antiulcerative activity.
The present invention therefore relates to novel cyclic amine derivative compounds, processes for their preparation, pharmaceutical compositions containing them and their use as medicaments, inter alia for the treatment or alleviation of Prostaglandin E mediated diseases such as pain, glaucoma, ulcerative colitis and osteoporosis. | 2 |
FIELD
[0001] This disclosure relates to the active reduction of harmonic noise from two or more rotating devices.
BACKGROUND
[0002] Engine harmonic cancellation systems are adaptive feed-forward noise reduction systems that are used in motor vehicles, for example in cabins or in muffler assemblies, to reduce or cancel engine harmonic noise. A sine wave at the frequency to be cancelled is used as an input to an adaptive filter. Engine harmonic cancellation systems also use one or more microphones as error input transducers. The adaptive filter can alter the magnitude and/or the phase of the input sine wave. The output of the adaptive filter is applied to one or more transducers that produce sound (i.e., loudspeakers) that is acoustically opposite to the undesirable engine harmonics that are to be canceled. The aim of the system is to cancel the noise at the frequency or frequencies of interest by adaptively minimizing the total energy across all error microphone input signals. In order to do so, the loudspeaker outputs have a negative gain.
[0003] Harmonic noise cancellation systems are also used to cancel or reduce noise caused by rotating devices other than engines. One additional source of noise in motor vehicles is the propeller shaft, also known as the drive shaft. Because geared transmissions are used to transfer engine rotation to propeller shaft rotation, the propeller shaft rotation rate is not fixed relative to the engine rotation rate. The engine and propeller shaft thus can be sources of noise in a vehicle cabin at different frequencies.
[0004] In order to cancel noise from both an engine and a propeller shaft, a noise reduction system requires two feed-forward adaptive filters. When the two frequencies being cancelled are coincident or close, the stability margins of the filters can be compromised. This increases the possibility of divergence of the filter algorithms, which can lead to the creation of loud and noticeable noise artifacts.
SUMMARY
[0005] The system and method of this disclosure are effective to reduce the audible artifacts that can be created by an adaptive feed-forward noise reduction system when two frequencies being cancelled are too close to each other. This can be accomplished by determining the proximity of the frequencies being cancelled and based on the proximity altering the operation of one or more of the adaptive filters.
[0006] All examples and features mentioned below can be combined in any technically possible way.
[0007] In one aspect, a system for reducing noise caused by a plurality of rotating devices by taking in a plurality of input signals with frequencies that are related to the rotation rates of the rotating devices and causing one or more loudspeakers to produce sounds that are at about the same frequencies as the noise and of substantially opposite phase, includes a plurality of noise cancellers, each noise canceller comprising a harmonic frequency computer that computes from an input signal a harmonic frequency and provides the harmonic frequency to a harmonic sine wave generator that generates an output sine wave, and an adaptive filter that uses a sine wave to create a noise reduction signal that is used to drive one or more transducers with their outputs directed to reduce noise caused by the rotating devices. There is also an overlap detector that compares the harmonic frequencies and, based on the proximity of the harmonic frequencies, alters the operation of one or more of the adaptive filters.
[0008] Embodiments may include one of the following features, or any combination thereof The overlap detector may alter the operation of one or more of the adaptive filters by changing the values of one or more variable parameters of an adaptive filter; the variable parameters can include the adaptation step sizes of the adaptive filters, where the step sizes are decreased when the proximities of the frequencies are close. For example, the adaptation step size may be decreased by about one-half when two input signal frequencies are approximately coincident. The system can also include a computer memory that stores relationships between the proximity of the frequencies and the resulting changes in the values of the adaptive filter parameters. The transducer outputs may be directed into the cabin of a motor vehicle. The rotating devices can be the vehicle engine and the vehicle propeller shaft.
[0009] In another aspect, a system for reducing noise caused by a plurality of rotating devices of a motor vehicle by taking in a plurality of input signals with frequencies that are related to the rotation rates of the rotating devices, and causing one or more loudspeakers to produce sounds that are at about the same frequencies as the noise and of substantially opposite phase, includes a plurality of noise cancellers, each noise canceller comprising a harmonic frequency computer that computes from an input signal a harmonic frequency and provides the harmonic frequency to a harmonic sine wave generator that generates an output sine wave, and an adaptive filter that uses a sine wave to create a noise reduction signal that is used to drive one or more transducers with their outputs directed so as to reduce noise in the vehicle cabin that is caused by the rotating devices. There is an overlap detector that compares the harmonic frequencies and, based on the proximity of the harmonic frequencies, alters the operation of one or more of the adaptive filters, wherein the overlap detector alters operation of one or more of the adaptive filters by changing the values of one or more variable parameters of an adaptive filter, wherein the variable parameters comprise the adaptation step sizes of the adaptive filters, and the step sizes are decreased when the proximities of the frequencies are close. A computer memory stores relationships between the proximity of the frequencies and the resulting changes in the values of the adaptive filter parameters. The rotating devices may be the vehicle engine and the vehicle propeller shaft.
[0010] In yet another aspect, a method for operating an active noise reduction system that is adapted to reduce noise caused by a plurality of rotating devices, where there are system input signals with frequencies that are related to the rotation rate of the rotating devices, and where the active noise reduction system comprises separate adaptive filters associated with each of the input signals, the adaptive filters having tuning parameters that affect their outputs, the adaptive filters outputting noise reduction signals that are used to drive one or more transducers with their outputs directed to reduce noise caused by the rotating devices, includes determining the proximity of the frequencies of the input signals and changing the values of one or more variable parameters based on the determined proximity of the frequencies of the input signals.
[0011] Embodiments may include one of the following features, or any combination thereof. The method may further include the step of storing in a computer memory relationships between the proximity of the frequencies and the resulting changes in the values of the adaptive filter parameters. The variable parameters can include the adaptation step sizes of the adaptive filters, and the step sizes may be decreased when the proximities of the frequencies are close. The adaptation step size may be decreased by about one-half when two input signal frequencies are approximately coincident. The values of the variable parameters may be computed and provided to the adaptive filters. The proximity of the frequencies may be determined by an overlap detector that provides control signals to affect the computation of the values of the variable parameters. The transducer outputs may be directed into the cabin of a motor vehicle. The rotating devices may comprise the vehicle engine and the vehicle propeller shaft.
[0012] In another aspect, a method for operating an active noise reduction system that is adapted to reduce noise caused by a plurality of rotating devices of a motor vehicle, where there are system input signals with frequencies that are related to the rotation rate of the rotating devices, and where the active noise reduction system comprises separate adaptive filters associated with each of the input signals, the adaptive filters having tuning parameters that affect their outputs, the adaptive filters outputting noise reduction signals that are used to drive one or more transducers with their outputs directed into the cabin of the motor vehicle so as to reduce noise in the cabin caused by the rotating devices, includes determining the proximity of the frequencies of the input signals. The values of one or more variable parameters are changed based on the determined proximity of the frequencies of the input signals, wherein the variable parameters comprise the adaptation step sizes of the adaptive filters, and the step sizes are decreased when the proximities of the frequencies are close, wherein the values of the variable parameters are computed and provided to the adaptive filters and wherein the proximity of the frequencies is determined by an overlap detector that provides control signals to affect the computation of the values of the variable parameters. A computer memory stores relationships between the proximity of the frequencies and the resulting changes in the values of the adaptive filter parameters. The rotating devices may be the vehicle engine and the vehicle propeller shaft.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 is a schematic block diagram of a harmonic cancellation system that can be used to accomplish the system, device and method of the present innovation.
[0014] FIG. 2 illustrates noise in a vehicle cabin.
DETAILED DESCRIPTION
[0015] Elements of FIG. 1 of the drawings are shown and described as discrete elements in a block diagram. These may be implemented as one or more of analog circuitry or digital circuitry. Alternatively, or additionally, they may be implemented with one or more microprocessors executing software instructions. The software instructions can include digital signal processing instructions. Operations may be performed by analog circuitry or by a microprocessor executing software that performs the equivalent of the analog operation. Signal lines may be implemented as discrete analog or digital signal lines, as a discrete digital signal line with appropriate signal processing that is able to process separate signals, as a multiplexed digital signal bus, and/or as elements of a wireless communication system.
[0016] When processes are represented or implied in the block diagram, the steps may be performed by one element or a plurality of elements. The steps may be performed together or at different times. The elements that perform the activities may be physically the same or proximate one another, or may be physically separate. One element may perform the actions of more than one block. Audio signals may be encoded or not, and may be transmitted in either digital or analog form. Conventional audio signal processing equipment and operations are in some cases omitted from the drawing.
[0017] FIG. 1 is a simplified schematic diagram of harmonic noise cancellation system 10 that embodies the disclosed innovation. In this non-limiting example system 10 is designed to cancel both engine noise and propeller shaft noise in the cabin of a motor vehicle. However, system 10 can be used to reduce harmonic noise emanating from any two or more rotating devices (e.g., motors). System 10 can also be used to reduce harmonic noise in locations other than motor vehicles and in volumes other than motor vehicle cabins. As one non-limiting example, system 10 could be used to cancel engine harmonics, prop shaft harmonics and harmonics due to the air conditioning compressor in a motor vehicle. In FIG. 1 signal flow is indicated with solid arrows and control signals are indicated by dash/dot lines with arrowheads.
[0018] System 10 in this case has two parallel harmonic noise cancellers: engine noise canceller 44 reduces or cancels engine harmonic noise in cabin 12 , while prop shaft noise canceller 46 reduces or cancels propeller shaft harmonic noise in cabin 12 . Each canceller can be implemented as computer code in the digital signal processor that is used to accomplish the adaptive filter. In this non-limiting example the adaptive algorithm is a filtered x adaptive algorithm. However, this is not a limitation of the innovation as other adaptive algorithms could be used, as would be apparent to those skilled in the technical field.
[0019] Each canceller 44 and 46 computes the harmonic frequencies to be cancelled from the input RPM: canceller 44 has harmonic frequency computer 24 that is input with the engine RPM, and canceller 46 has harmonic frequency computer 31 that is input with the prop shaft RPM. Each canceller has a harmonic sine wave generator ( 25 and 32 , respectively) that generates sine waves at the frequencies to be cancelled. Sine wave generators 25 and 32 are input with the computed harmonic frequencies based on the inputs from the rotating devices that are to be cancelled. Adaptive filters 20 and 36 , respectively, supply transducer drive signals to one or more output transducers 14 that have their outputs directed into vehicle cabin 12 . The residual noise after the output of the transducers, as modified by the cabin transfer function 16 , is combined with the engine noise and propeller shaft noise in the vehicle cabin and is picked up by an input error transducer (e.g., microphone) 18 .
[0020] Sine wave generator 25 provides to adaptive filter 20 a noise reduction reference signal that includes the harmonics of the engine frequency that are to be cancelled using adaptive filter 20 . The output of sine wave generator 25 , which is referred to as the “x signal,” is also provided to modeled cabin transfer function 26 , to produce a filtered x signal. The filtered x signal and the microphone output signals are multiplied together 27 , and provided as a control input to adaptive filter 20 . Similarly, sine wave generator 32 provides to adaptive filter 36 a noise reduction reference signal that includes the harmonics of the propeller shaft frequency that are to be cancelled using adaptive filter 36 . The output of sine wave generator 32 is also provided to modeled cabin transfer function 33 , to produce a filtered x signal. The filtered x signal and the microphone output signal are multiplied together 38 , and provided as a control input to adaptive filter 36 . The operation of adaptive feed-forward harmonic noise cancellation systems is well understood by those skilled in the art.
[0021] Overlap detector 42 takes in as control signals from frequency computers 24 and 31 the harmonic frequencies that are going to be cancelled, and makes a decision of when the frequencies are close enough to affect the stability margin. If so, it causes the adaptive filters to automatically change the value of one or more variables of the adaptive algorithm. In the present case in which a filtered x adaptive algorithm is used, the variables that are changed can be one or both of the adaptation step size and the leakage parameter. Adaptation step size and leakage in an adaptive algorithm are disclosed in U.S. Pat. Nos. 8,194,873, 8,204,242, 8,355,512, and 8,306,240, the disclosures of which are incorporated herein by reference.
[0022] More generally, changes are made by the system to one or more of the filtration algorithms with the aim of maintaining the stability margin so as to keep the performance of the system close to what it would be with a single canceller. A reason that performance can be maintained to an acceptable level when the overlap happens is that multiple cancellers are working at the same frequency region instead of just one. In general, the detector can have multiple degrees of overlap, and for each it can have ability to select from predetermined values of the appropriate adaptive algorithm parameters.
[0023] As one non-limiting example: If the prop shaft canceller is set to cancel the first order prop harmonic frequency and the prop RPM is 3000, the first order prop harmonic frequency is 50 Hz (1×3000/60). If the engine canceller is set to cancel the 1.5 order engine harmonic frequency and in the current gear the engine RPM is 2000, the 1.5 order engine frequency would be 50 Hz (1.5×2000/60). In this example the two frequencies to be cancelled are exactly the same, so both adaptive filters 20 and 36 will produce the same cancellation frequency. The degree by which the engine and prop frequencies overlap will vary with the gear ratio, or within the same gear one can have torque convertor slippage which can also cause the frequencies to overlap.
[0024] Generally, two cancellers working at the same frequency means that the cancellation is more effective, as the cancellation system's adaptation step size is effectively doubled. However, the larger adaptation step size means that there is less margin for transfer function variation before the system will become unstable and potentially diverge.
[0025] The present innovation can account for the increase in cancellation algorithm adaptation step size when the two frequencies being cancelled are coincident or close to each other. In the example described just above, by automatically decreasing the adaptation step size by 0.5 the original single canceller performance is maintained and so the original stability margin is regained.
[0026] It may be advantageous to allow a margin in the estimated transfer function, as in the real world each production car will have variation from the one that was used to do the original tuning due to component tolerances, temperature variation, passenger/cabin loading etc. In practice the reduction in adaptation step size may not be exactly 0.5. More specifically, one or more adjustable filter parameters can be empirically chosen so as to maintain optimum cancellation and stability margin. These parameters can be empirically determined at time of tuning to accomplish the best tradeoff to handle the overlapping condition. Other conditions such as noise source location will determine what the optimum would be. Also, the cancellers can have the capability to adjust other adaptive algorithm parameters, such as leakage, as necessary to maintain the right balance of performance and stability margin. In cases in which an algorithm other than the filtered x adaptive algorithm is used in the adaptive filters, other variables that are mutually effective can be chosen to be modified in a similar manner with the goal of maintaining the original single canceller performance and thus regain the original stability margin.
[0027] The above example was for an idealized case where there is perfect overlap. More generally, stability margin can be lost when the frequencies are close. So, overlap detector 42 can be set for the proximity of the two (or more) frequencies, multiple frequencies being another tunable parameter that is determined empirically at time of tuning. Likewise, the system can account for more than one band of overlap. The system can be expanded to multiple levels of overlap, with each having independent changes to the selected filter parameters, the values typically being determined empirically a priori and then stored in computer memory and retrieved during operation of the system based on the proximity of the two frequencies. More generally in the example described herein, the change in adaptation step size can be set as a function of the proximity of the two frequencies. When there are more than two frequencies being cancelled, a pair-wise comparison of all the frequencies would be used.
[0028] One result of the subject innovation is that the harmonic cancellation systems are less likely to diverge. Another benefit is that detectable noise artifacts due to system instability are minimized.
[0029] An idealized, non-limiting example of a manner in which the innovation can operate is illustrated with reference to FIG. 2 , which illustrates an example of algorithm adjustment due to overlapping cancellation frequencies in a noise cancellation system such as that shown in FIG. 1 that is designed and operated to cancel engine harmonics and propeller shaft harmonics in a motor vehicle cabin. The engine RPM (input from the vehicle's tachometer) is set out along the x axis, with the cabin noise sound pressure level (SPL) on the y axis, in dB. Curve 102 illustrates the baseline noise, and curve 104 illustrates the reduction in noise when the cabin engine and prop shaft harmonic noise cancellation system is turned on, with the two cancellers operating at the same frequency. Curve 104 illustrates a reduction of about 10 dB across most of the normal automobile operating range.
[0030] Curve 106 (in dashed line) illustrates an excursion in the sound when the engine and prop shaft noise cancellation systems are both on and there is a change in cabin transfer function that results in the creation of noise artifacts that increase the sound levels quite dramatically around the frequency corresponding to around 3000 RPM. The system disclosed herein would be enabled to alter the values of one or more parameters of the adaptive filter algorithm to bring the operation back closer to curve 104 , where it would be if only one canceller was being used.
[0031] The above was described relative to noise cancellation in a vehicle cabin. However, the disclosure applies as well to noise cancellation in other vehicle locations. One additional example is that the system can be designed to cancel noise in a muffler assembly. Such noise may be engine harmonic noise but may also be other engine-operation related noise and/or noise caused by another rotating device in the vehicle.
[0032] Embodiments of the devices, systems and methods described above comprise computer components and computer-implemented steps that will be apparent to those skilled in the art. For example, it should be understood by one of skill in the art that the computer-implemented steps may be stored as computer-executable instructions on a computer-readable medium such as, for example, floppy disks, hard disks, optical disks, Flash ROMS, nonvolatile ROM, and RAM. Furthermore, it should be understood by one of skill in the art that the computer-executable instructions may be executed on a variety of processors such as, for example, microprocessors, digital signal processors, gate arrays, etc. For ease of exposition, not every step or element of the systems and methods described above is described herein as part of a computer system, but those skilled in the art will recognize that each step or element may have a corresponding computer system or software component. Such computer system and/or software components are therefore enabled by describing their corresponding steps or elements (that is, their functionality), and are within the scope of the disclosure.
[0033] The various features of the disclosure could be enabled in different manners than those described herein, and could be combined in manners other than those described herein. A number of implementations have been described. Nevertheless, it will be understood that additional modifications may be made without departing from the scope of the inventive concepts described herein, and, accordingly, other embodiments are within the scope of the following claims. | A system and method for reducing noise caused by two or more rotating devices by taking in input signals with frequencies that are related to the rotation rates of the rotating devices, and causing one or more loudspeakers to produce sounds that are at about the same frequencies as the noise and of substantially opposite phase. There is a noise canceller associated with each rotating device. Each noise canceller includes a harmonic frequency computer that computes a harmonic frequency and provides the harmonic frequency to a harmonic sine wave generator that generates an output sine wave. Each nose canceller also has an adaptive filter that uses a sine wave to create a noise reduction signal that is used to drive one or more transducers with their outputs directed to reduce noise caused by the rotating devices. There is an overlap detector that compares the harmonic frequencies and, based on their proximity, alters the operation of one or more adaptive filters. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
The present application is a continuation of U.S. application Ser. No. 11/957,317, filed Dec. 14, 2007, which is a continuation of U.S. application Ser. No. 10/812,156 filed Mar. 29, 2004, now U.S. Pat. No. 7,375,216, issued May 20, 2008, which is a continuation-in-part of U.S. application Ser. No. 10/453,815, filed on Jun. 2, 2003, now U.S. Pat. No. 6,818,763, issued Nov. 16, 2004, which claims the benefit of U.S. Provisional Application No. 60/385,498, filed on Jun. 4, 2002, the disclosures of which are incorporated by reference herein.
BACKGROUND OF THE INVENTION
The present invention generally relates to metal mesoporphyrin halide compounds and processes for their preparation. More specifically, it relates to processes for making novel intermediate compounds, which can be converted to such mesoporphyrin halide compounds.
Tin (IV) mesoporphyrin IX dichloride or stannsoporfin is a chemical compound having the structure indicated in FIG. 1 . It has been proposed for use, for example, as medicament in the treatment of various diseases including, for example, psoriasis (U.S. Pat. No. 4,782,049 to Kappas et al.) and infant jaundice (for example, in U.S. Pat. Nos. 4,684,637, 4,657,902 and 4,692,440). Stannsoporfin is also known to inhibit heme metabolism in mammals, to control the rate of tryptophan metabolism in mammals, and to increase the rate at which heme is excreted by mammals (U.S. Pat. Nos. 4,657,902 and 4,692,400 both to Kappas et al.).
Processes for obtaining stannsoporfin are known in the art. Protoporphyrin IX iron (III) chloride or hemin, of the structural formula indicated in FIG. 2 , is commonly used as starting material. The hemin is generally hydrogenated to form an intermediate mesoporphyrin IX dihydrochloride, which is subsequently subjected to tin insertion, yielding stannsoporfin.
One prior method for the preparation of the intermediate mesoporphyrin IX dihydrochloride has involved catalytic hydrogenation of hemin over Pd(0) in formic acid at elevated temperature. Column chromatography of the resulting intermediate obtained by such a method yields an intermediate mesoporphyrin IX dihydrochloride product that reportedly contains about 15% of an unidentified impurity. Another preparation method for this intermediate has been typically performed at lower temperatures with heating hemin in formic acid in the presence of palladium catalyst. This process is reported to reduce the amount of the unidentified impurity; however, the reaction is difficult to drive to completion without decomposition of the intermediate product.
The above referenced methods for the preparation of the mesoporphyrin IX intermediate are used to produce only small, gram scale quantities of the product, and the product further requires subsequent isolation and purification, generally by preparative or column chromatography. Additionally, those methods in which hydrogenation is carried out at lower temperatures yield incomplete reactions, and when higher temperatures are used, degradation of the intermediate product is observed. Consequently, the crude intermediate product requires purification. Furthermore, the above referenced procedures require exceedingly high solvent volumes, thus making the process unsuitable for industrial scale up, since isolation of mesoporphyrin IX dihydrochloride or its free base is performed using a filtration process. Such filtrations and subsequent washings of the products are time-consuming, making the large-scale isolations costly and difficult. Additionally, the limited stability of mesoporphyrin IX in hydrochloric acid at the elevated temperatures required to form the dihydrochloride also complicates the industrial scale up of this process.
The insertion of various metals into porphyrin rings has been described by Fischer and Neumann (Ann. Chem. (1932), 494, 225). The reaction for the insertion of tin is performed in an acid, typically acetic acid, and further typically under reflux, using Sn (II) in the presence of an oxidant. A modified process is also described by Fuhrhop and Smith, as reported in “Porphyrins and Metalloporphyrins” p. 757, Elsevier, Amsterdam, 1975, to include sodium acetate, which buffers the solution and enhances deprotonation of the porphyrin. In most cases, the metal mesoporphyrin halide product crystallizes directly from the reaction mixture on cooling. Such crystallization may be enhanced by the addition of water or methanol.
SUMMARY OF THE INVENTION
One or more embodiments of the present invention provides a novel process for the preparation of metal mesoporphyrin halides that overcomes some of the difficulties of the processes known in the art.
It has now been discovered that, if the catalytic hydrogenation of hemin is conducted in formic acid, in two distinct states, each using different reaction conditions, a novel intermediate compound, a mesoporphyrin IX formate, is formed. This compound can be precipitated so that it can be isolated in a substantially pure, solid form. Then the substantially pure formate intermediate can be reacted to form a metal mesoporphyrin halide. This reaction of the formate intermediate can be accomplished in a single reaction with a metal to form a metal mesoporphyrin halide. Alternatively, the mesoporphyrin formate can be purified, and the purified intermediate can be used to form a metal mesoporphyrin halide. In another embodiment, the purified or unpurified mesoporphyrin formate can be converted to a mesoporphyrin IX dihydrochloride and reacted with insert metals such as tin, and obtain metal mesoporphyrin halides with a high degree of purity, capable of further purification if necessary, by simple procedures capable of being conducted on an industrial scale. Preferably, the intermediate formate is purified, converted to a mesoporphyrin dihydrochloride, and the mesoporphyrin dihydrochloride is reacted to form a metal mesoporphyrin halide.
Thus the invention provides, from one aspect, a process of preparing a mesoporphyrin IX formate, which comprises subjecting hemin to catalytic hydrogenation in formic acid, said hydrogenation being conducted in two successive steps comprising a first step of subjecting a mixture of hemin and a hydrogenation catalyst in formic acid to a first temperature and pressure for a first period of time. In one embodiment, the hydrogen pressure may be between about 30-60 psi and the temperature may be between about 85-95° C. The temperature may be held within that range for a period of about 1-3 hours.
A second step includes subjecting the mixture to a second temperature and pressure for a second period of time. In one embodiment, the second hydrogen pressure can be between about 30-60 psi and the temperatures may be between about 45-50° C. The mixture may be held to this temperature for a period of between about 3-6 hours. Mesoporphyrin IX formate is then recovered from the reaction mixture by precipitation with an organic solvent, for example an ether. Mesoporphyrin IX formate, which has the structural chemical formula indicated in FIG. 3 , is a novel chemical compound.
Alternatively and preferably, the reactor may be pressurized with hydrogen gas prior to the heating step. Pressurizing the reactor with hydrogen prior to heating, in the first step of the process, reduces degradation, while exceeding the times and the temperatures set out above for the first step increases degradation. On the other hand, shorter reaction times and lower temperatures will lead to undesirable decreases in conversion, leading to low product yields. The second step as defined above completes the conversion of the hemin (Protoporphyrin IX iron (III) chloride) to mesoporphyrin IX formate.
Isolation of the intermediate product as a formate provides a readily filterable intermediate, filtering and washing of which to obtain at least a substantially high purity intermediate product (about >97%) is a simple procedure. The purity of the intermediate is important in the manufacturing of the final product, whether stannsoporfin or other metal mesoporphyrin halides, in that a higher purity intermediate produces a higher purity product. According to one or more embodiments, the mesoporphyrin IX formate intermediate can then be subjected to further purification such as reaction with metal scavengers and then converted to metal mesoporphyrin IX dihydrochloride.
Another aspect of the present invention comprises a process of converting a mesoporphyrin IX dihydrochloride to a metal mesoporphyrin halide which comprises subjecting the mesoporphyrin IX dihydrochloride to a chemical metal insertion process by reaction with a metal halide compound, under buffered, acidic reaction conditions and in the presence of an oxidant; and recovering the metal mesoporphyrin halide from the reaction mixture.
The invention provides, in another aspect, a process of purification of a metal mesoporphyrin halide, which comprises the steps of dissolving the metal mesoporphyrin halide in an aqueous basic solution to obtain a dissolved metal mesoporphyrin halide; treating said dissolved metal mesoporphyrin halide with charcoal to obtain a treated metal mesoporphyrin halide; adding said treated metal mesoporphyrin halide to a first aqueous acid solution to obtain a precipitated metal mesoporphyrin halide; triturating said precipitated metal mesoporphyrin halide in a second aqueous acid solution at elevated temperature to obtain a pharmaceutical grade pure (about or more than 97%) metal mesoporphyrin halide; and drying the pharmaceutical grade pure metal mesoporphyrin halide.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates the chemical structure of tin mesoporphyrin chloride (tin (IV) mesoporphyrin IX dichloride) or stannsoporfin.
FIG. 2 illustrates the chemical structure of protoporphyrin IX iron (III) chloride or hemin,
FIG. 3 illustrates the chemical structure of mesoporphyrin IX formate;
FIG. 4 illustrates the conversion of protoporphyrin IX iron (III) chloride (ferriporphyrin chloride or hemin) to mesoporphyrin IX formate to mesoporphyrin IX dihydrochloride, in accordance with one embodiment invention; and
FIG. 5 illustrates the conversion of mesoporphyrin IX dihydrochloride to a tin mesoporphyrin chloride (tin (IV) mesoporphyrin IX dichloride) or stannsoporfin, in accordance with an embodiment of the invention.
DETAILED DESCRIPTION
According to one embodiment of the invention, illustrated in accompanying FIG. 4 , hemin is hydrogenated in formic acid, over an appropriate metal catalyst such as, for example, palladium, platinum or nickel, among others, under a hydrogen atmosphere, at elevated temperatures. Preferred embodiments of the invention involve the use of palladium on carbon as metal catalyst. According to one or more embodiments, in the first stage of hydrogenation, the temperature of hydrogenation is held at about 85-95° C. for a period of about 1-3 hours. Most preferred conditions are a temperature of about 90° C. and a time of about 1 hour.
In one or more in embodiments, in the second stage of hydrogenation, the reaction mixture is cooled to about 45-50° C. and hydrogenated for a further period of time of about 3-6 hours, in order to convert substantially all hemin (protoporphyrin IX iron (III) chloride) to mesoporphyrin IX formate. This second stage is also conducted in formic acid. The same catalyst may be used as above, so that the two stages of the process may be conducted in the same reactor. Optionally, a further charge of hydrogen may be supplied to the reactor prior to commencing the second stage. The second hydrogenation stage increases the yield of the mesoporphyrin IX formate, while reducing the amount of impurities in the final metal mesoporphyrin halide.
In contrast to previously described methods, the mesoporphyrin IX intermediate compound in the present invention is not isolated as a dihydrochloride, but rather as a formate salt.
The mesoporphyrin IX formate may be isolated from the formic acid solution by the addition of a solvent such as an ether or other organic solvent, leading directly to the mesoporphyrin IX formate intermediate, which is further subjected to drying. Ethers such as, for example, methyl tert-butyl ether, diethyl ether or di-isopropyl ether, among others, may be used. Preferred embodiments of the invention involve methyl tert-butyl ether.
The amounts of solvent used in the process according to the invention are much lower than those used in the referenced processes that involve the formation of a dihydrochloride intermediate; such smaller volumes allow for less filter time. Ratios of amount of hemin to amount of solvent of about 1:10 to about 1:20 may be used. In addition, the filtration and washings of the mesoporphyrin IX formate are rapid. After drying, the crude intermediate formate is obtained, in high yields (about 80-95%) and its purity, established by HPLC, is about or above 97%. The intermediate formate obtained in accordance with the process of the invention is of quality equal to or better than that of the intermediate mesoporphyrin IX dihydrochloride produced in the process described in the prior art, after purification by preparative chromatography.
According to one or more embodiments of the present invention, the mesoporphyrin IX formate obtained above and shown in FIG. 4 can be further purified by dissolving the formate in formic acid. A metal scavenger may be utilized to purify the formate to remove residual metal catalysts. After the scavenger is removed, the mesoporphyrin IX formate solution is mixed with hydrochloric acid to convert the formate to mesoporphyrin IX dihydrochloride. Preferred metal scavengers include, but are not limited to, silica bound scavengers such as Si-thiol, Si-thiourea, Si-triamine, and Si-triaminetetraacetatic acid, which are available from Silicyle® Incorporated. The purification process is carried out for a time sufficient to remove residual metal catalyst such as palladium, which would otherwise remain as an impurity. Preferably, the purification process proceeds for more than 10 hours and less than 20 hours, for example, about 16 hours. It will be understood that the invention is not limited to any particular time, and that longer times may result in a higher purity product. The metal scavenger is then removed by charging a filtering aid such as celite and additional formic acid into the mixture. Then, the mixture is filtered to provide filtrate, which is vacuum distilled and cooled to concentrate the filtrate. The concentrated filtrate is then added to 1 N hydrochloric acid, and the resultant suspension is isolated by filtration to form mesoporphyrin IX dihydrochloride. Applicants have discovered that these additional processing steps to scavenge metal from the mesoporphyrin IX formate intermediate and form a mesoporphyrin IX dihydrochloride intermediate yields a higher purity end product (tin mesoporphyrin IX dichloride).
The insertion of metal into mesoporphyrin IX dihydrochloride to obtain metal mesoporphyrin halide is described below with specific reference to tin, to prepare stannsoporfin, a known pharmaceutical and a specific preferred embodiment of the invention. It is not intended that the scope of the invention should be limited thereto, but is generally applicable to preparation of mesoporphyrin halides, for example, but not limited to, mesoporphyrin chlorides, of other metals such as, for example, iron, zinc, chromium, manganese, copper, nickel, magnesium, cobalt, platinum, gold, silver, arsenic, antimony, cadmium, gallium, germanium and palladium, among others.
Preparation of mesoporphyrin halides of these other metals simply entails a substitution of a halide such as chloride, bromide or iodide of the chosen metal in place of stannous chloride in the process described, in substantially equivalent amounts.
The second stage of the process according to one or more embodiments of the invention is illustrated in FIG. 5 . Mesoporphyrin IX dihydrochloride is subjected to heating with a tin (II) carrier in acetic acid, in the presence of an oxidant, at reflux. Preferably, the heating is performed with aeration, for example, by an inflow of 6% oxygen mixed with nitrogen for about 24-48 hours. Air inflow could also be used to aerate during heating. Tin (II) carriers such as tin (II) halides or tin (II) acetate can be used. The reaction may also be carried out in the presence of suitable acetate counter ions include ammonium, sodium or potassium ions. Oxidants such as oxygen from air or in pure form as well as hydrogen peroxide can also be used. In one exemplary embodiment of this second stage, mesoporphyrin IX formate is subjected to heating with tin (II) chloride in acetic acid, buffered with ammonium acetate, and the reaction is conducted with aeration, at reflux. The ammonium acetate can be eliminated. Tin mesoporphyrin chloride is isolated from the reaction mixture by the addition of water, followed by filtration. Prior to drying at about 90-100° C., the cake is triturated into hot, dilute hydrochloric acid, preferably of concentration of about 0.1N-6N, at an elevated temperature, of about 90-100° C. The crude, substantially pure tin mesoporphyrin chloride (crude tin (IV) mesoporphyrin IX dichloride) is obtained with a yield of about 75-95% and a purity of about 95%, as judged by HPLC analysis.
The tin mesoporphyrin chloride so obtained may be further purified by dissolving the product in an aqueous inorganic base solution, preferably dilute ammonium hydroxide, followed by treatment with charcoal. The product is then re-precipitated by addition to an acid solution, such as acetic acid, hydrochloric acid or a mixture thereof. The above dissolving charcoal treatment and re-precipitation steps may be repeated a number of times, typically about 1-3 times in order to ensure the desired purity. Prior to drying, the cake is triturated in hot, dilute hydrochloric acid of a concentration of about 0.1N-6N, at an elevated temperature of about 90-100° C., in order to remove any residual ammonium salts. The tin mesoporphyrin chloride product (tin IV) mesoporphyrin IX dichloride or stannsoporfin) is obtained in a yield of about 50-70%, with an HPLC purity of about or greater than 97%.
The invention may also be performed to produce substantially pure or pharmaceutical quality tin mesoporphyrin chloride (tin (IV) mesoporphyrin IX dichloride or stannsoporfin) in large scale quantities, such as quantities exceeding about 0.1 kg through and including multiple kilogram amounts, by slight modifications of the above procedure, such as increased reaction or drying times as appropriate based upon the increase in scale of the starting reactants. Temperature and pressure times likewise can be modified as needed within the scope of this invention. The tin mesoporphyrin chloride product (tin (IV) mesoporphyrin IX dichloride or stannsoporfin) is obtained in the large-scale production process in a yield of about 60-90%, with an HPLC purity of about 97%.
The invention will be further described, for illustrative purposes, with reference to the following specific experimental examples.
EXAMPLE 1
Preparation of Mesoporphyrin IX Formate
A 2000 ml hydrogenation vessel was charged with 40.0 g hemin, 4.0 g 5% Pd/C (50% water by weight), and 800 ml 96% formic acid. Since hemin and mesoporphyrin IX formate as well as all reaction intermediates are reportedly light sensitive materials, care was taken throughout this entire procedure to minimize the exposure of the reaction to visible or ultraviolet light.
The vessel was flushed with a nitrogen flow for 10 minutes. With vigorous stirring, it was then pressurized to 50 psi with hydrogen for ten minutes; then depressurized, and the cycle repeated. The vessel was further pressurized to 50 psi with hydrogen and the temperature was raised to 90° C. over approximately 20 minutes.
The hydrogenation reaction was maintained at 90° C. and 45-55 psi for 1-1.5 hours. The reaction mixture was not stable for extended periods of time at 90° C. The time at this temperature was sufficient to dissolve all hemin and convert the majority of this material to the intermediate and final product, mesoporphyrin IX formate. The reaction was cooled to 50° C./50 psi over 20 minutes. This pressure and temperature were maintained for 3 hours. The reaction mixture was shown to be stable at this temperature for up to 48 hours. The reaction was cooled to 20-25° C., de-pressurized, and flushed with nitrogen.
The catalyst was removed by filtration through a bed of 20 g celite. The filter cake was rinsed with 3×50 ml formic acid and the filtrate was charged to a 2000 ml three-necked, round-bottom flask equipped with a magnetic stirbar, thermometer, and distillation bridge. The formic acid solvent was distilled off under aspirator vacuum to a residual volume of 200 ml. The distillation bridge was replaced with an addition funnel. With moderate agitation, 800 ml methyl tert-butyl ether was added drop wise over 30-60 minutes. The resultant suspension was agitated at 20-25° C. for 60 minutes prior to cooling to −20 to −25° C. for 1 to 2 hours. The suspension was filtered under reduced pressure. The filtercake was rinsed with 100 ml filtrate, followed by 2×50 ml methyl tert-butyl ether and dried under high vacuum at 40-60° C. for 24 hours. About 30-38 g of mesoporphyrin IX formate were obtained (yield of 75-95%).
EXAMPLE 2
Preparation of Substantially Pure Tin Mesoporphyrin Chloride (Tin (IV) Mesoporphyrin IX Dichloride or Stannsoporfin)
A dark 1000 ml three-necked, round-bottom flask equipped with a mechanical stirrer, condenser, bubbler, and an aeration tube was charged with 30.0 g mesoporphyrin IX formate, 34.5 g tin (II) chloride, 7.1 g ammonium acetate, and 600 ml acetic acid. The suspension was stirred at 20-25° C. for 30 minutes. Mesoporphyrin IX formate and tin mesoporphyrin as well as all reaction intermediates are reportedly light sensitive materials therefore care was taken throughout this entire procedure to minimize the exposure of the reaction to light.
The reaction was warmed to reflux, with aeration, for 3 to 4 hours. The reaction was shown to be stable at 110-115° C. for up to 48 hours. Once complete, the reaction mixture was cooled to 60-70° C. and 300 ml water was added while cooling to 20-25° C. over 60 minutes. The suspension was filtered under reduced pressure. The filtercake was rinsed with 2×60 ml water. A dark, 1000 ml, three-neck, round-bottom, flask equipped with a stir bar, thermometer, condenser, and nitrogen purge was charged with the wetcake from the above step, and 500 ml 1N HCl. The resultant suspension was warmed to 90° C. for 1 hour. The suspension was filtered under reduced pressure. The filtercake was rinsed with 2×50 ml 0.1N HCl and dried under high vacuum at 80-90° C. for 24 hours. About 25 to 28 g of crude, substantially pure (about or exceeding 95% purity) tin mesoporphyrin chloride (tin (IV) mesoporphyrin IX dichloride or stannsoporfin) was obtained for a yield of about 83-93%.
EXAMPLE 3
Further Purification of Crude, Substantially Pure Tin (IV) Mesoporphyrin Chloride (Tin (IV) Mesoporphyrin IX Dichloride or Stannsoporfin)
A darkened, 250 ml, one-neck, round-bottom flask equipped with a magnetic stirbar and nitrogen purge was charged with: 10.0 g tin (IV) mesoporphyrin chloride (tin (IV) mesoporphyrin IX dichloride), 125 ml water, and 4 ml 28% ammonium hydroxide, a sufficient amount of ammonium hydroxide to adjust the pH to 9.0-10.0. The suspension was stirred at 20-25° C. for 20-30 minutes to effect dissolution. As tin (IV) mesoporphyrin is light sensitive, dark conditions were maintained throughout this reaction sequence.
The flask was charged with 0.5 g Darco KB, and a 1.5 g Celite. The dark suspension was stirred at 20-25° C. for 1 hour. The suspension was filtered under reduced pressure through a bed of celite using a 5.5 cm Buchner funnel. The flask and filtercake were rinsed with 2×10 ml water. A dark, 1 L, one-neck, round-bottom flask equipped with a magnetic stirbar, addition funnel and nitrogen purge was charged with 375 ml acetic acid, and 10 ml 37% hydrochloric acid. The filtrate from the celite filtration step was charged to the addition funnel and added dropwise to the stirring acid solution over 30-45 minutes. The suspension was stirred at 20-25° C. for 1-2 hours; then filtered under reduced pressure using a 7 cm Buchner funnel. The filtercake was rinsed with 2×10 ml water.
A darkened, 250 ml, one-neck, round-bottom flask equipped with a magnetic stirbar and nitrogen purge was charged with the tin mesoporphyrin wet cake from the above step, 125 ml water and 4 ml 28% ammonium hydroxide. The suspension was stirred at 20-25° C. for 20-30 minutes to effect dissolution and the pH adjusted to about 9.0-10.0 with additional ammonium hydroxide. The flask was charged with 0.5 g Darco KB, and 1.5 g Celite. The dark suspension was stirred at 20-25° for 1 hour. The suspension was filtered under reduced pressure through a bed of celite using a 5.5 cm Buchner funnel. The flask and filtercake were rinsed with 2×10 ml water.
A dark L one-neck, round-bottom flask equipped with a magnetic stirbar, addition funnel and nitrogen purge was charged with 375 ml acetic acid, and 10 ml 37% hydrochloric acid. Once the addition was complete, the pH was adjusted to about less than or equal to 1 by the addition of 37% hydrochloric acid. The filtrate from the above celite filtration step was charged to the addition funnel and added dropwise to the stirring acid solution over 30-45 minutes. Once the addition was complete, the pH was adjusted to about less than or equal to 1 by the addition of hydrochloric acid. The suspension was stirred at 20-25° C. for 1-2 hours; then filtered under reduced pressure using a 7 cm Buchner funnel. The filtercake was rinsed with 2×10 ml water.
A darkened, 250 ml, one-neck, round-bottom flask equipped with a magnetic stirbar and nitrogen purge was charged with tin mesoporphyrin wet cake from the above step, 125 ml water, and 4 ml 27% ammonium hydroxide. The suspension was stirred at 20-25° C. for 20-30 minutes to effect dissolution. The pH was adjusted to about 9.0-10.0 with additional ammonium hydroxide. The flask was charged with 0.5 g Darco KB, and 1.5 g Celite. The dark suspension was stirred at 20-25° C. for 1 hour. The suspension was filtered under reduced pressure through a bed of celite using a 5.5 cm Buchner funnel. The flask and filtercake were rinsed with 2×10 ml water.
A dark 1 L one-neck, round-bottom flask equipped with a magnetic stirbar, addition funnel and nitrogen purge was charged with 375 ml acetic acid, and 10 ml 37% hydrochloric acid. The filtrate from the celite filtration step was charged to the addition funnel and added dropwise to the stirring acid solution over 30-45 minutes. Once the addition was complete, the pH was adjusted to about less than or equal to 1 by the addition of hydrochloric acid. The suspension was stirred at 20-25° C. for 1-2 hours; then filtered under reduced pressure using a 7 cm Buchner funnel. The filtercake was rinsed with 2×10 ml water.
A dark 500 ml, one-neck, round-bottom flask equipped with a stirbar, condenser, and nitrogen purge was charged with tin mesoporphyrin wetcake from the above step and 200 ml 1N HCl. The suspension, which ideally has a red color, was warmed to about 85-90° C. for 1-2 hours. The reaction was cooled to 20-25° C. and the suspension was filtered under reduced pressure using a 7 cm Buchner funnel. The filter cake was rinsed with 2×20 ml 0.1N HCl and dried at 85-90° C. for 24-48 hours. About 5 to 7 g of pharmaceutical grade pure tin mesoporphyrin chloride (tin (IV) mesoporphyrin IX dichloride) were obtained, for about a 50-70% yield, with a purity greater than or equal to 99%, as judged by HPLC analysis.
EXAMPLE 4
Representative Large Scale Production of Tin Mesoporphyrin IX Chloride (Tin (IV) Mesoporphyrin IX Dichloride or Stannsoporfin)
Step 1
A 200 L reaction vessel, which has been pressure tested and inerted with nitrogen, is charged with 0.6 kg of 5% palladium on carbon (50% water by weight). Without agitation, the vessel is charged with 6.0 kg hemin and 161.0 kg formic acid, while minimizing the exposure of the ingredients throughout this reaction to visible or ultraviolet light. The vessel is pressurized with hydrogen to 30-35 psi at 20-25° C. The reaction mixture is agitated vigorously for a minimum of 30 minutes and warmed to 85-90° C. With vigorous agitation, the reaction temperature is maintained at 85-90° C. with a hydrogen pressure of 45-55 psi for a period of 60-75 minutes. The reaction is then cooled to 45-50° C. while maintaining pressure and hydrogenation is continued for a further 6 hours. The reaction is cooled to 20-25° C. The reactor is depressurized and inerted (flushed) with nitrogen. The reactor is charged with a dispersion agent, such as 3.0 kg hyflo supercel, suspended in 36 kg formic acid. The reaction mixture is then filtered to remove the catalyst.
The filtercake is rinsed with 2×61 kg formic acid. 170 L of the filtrate is transferred to a 200 L reaction vessel and cooled to 10-15° C. The reaction mixture is distilled under a reduced pressure of 20-60 mmHg, with a maximum reactor temperature of 50° C., to a residual volume of 25-35 L. The remainder of the filtrate is transferred into the reactor and cooled to 10-15° C. The reaction mixture is distilled under a reduced pressure of 20-60 mmHg, with a maximum reactor temperature of 50° C., to a residual volume of 25-35 L. The temperature of the reactor is cooled to 20-25° C. The reaction vessel is charged with 89.1 kg methyl tert-butyl ether over a minimum of 1 hour. Upon completion of the addition, the reaction is agitated at 20-25° C. for a minimum of 2 hours. The reaction mixture is cooled to −20 to −25° C. over a minimum of 1 hour. The reaction is agitated at −20 to −25° C. for a period of 4 hours. The suspension is filtered through a cotton terylene cloth at −20 to −25° C. The filtercake is rinsed with 2×6 kg methyl tert-butyl ether. The product is dried under vacuum with a maximum oven temperature of 55° C. until it passes drying specifications. Once dry, the product (mesoporphyrin IX formate) is packaged. The theoretical yield for this reaction is 6.1 kg. Typically, the product is isolated with a yield of 4.6-5.8 kg (75-95%).
Step 2
An inerted reaction vessel is charged with 5.3 kg tin (II) chloride, 1.1 kg ammonium acetate, and 45.3 kg acetic acid. The suspension is moderately agitated at 20-25° C. for a minimum period of 2 hours. An inerted 200 L reaction vessel is charged with 4.6 kg mesoporphyrin IX formate from step 1, and 45.0 kg acetic acid. The mesoporphyrin suspension is warmed to 45-55° C. with moderate agitation for a period of 2 hours. With moderate agitation, under nitrogen, the tin chloride suspension is transferred into the mesoporphyrin suspension while maintaining a temperature of 45-55° C. in the vessel. The transfer lines are rinsed with 5.9 kg acetic acid. With vigorous agitation, nitrogen and air are bubbled into the reaction at such a rate so as to maintain an oxygen level less than 2% within the reactor. This aeration is maintained throughout the reaction. With vigorous agitation, the reaction mixture is warmed to reflux (ca. 110° C.) for a minimum period of 3 hours.
The reaction is cooled to 60-70° C. and 45.8 kg purified (de-ionized) water is added over a minimum of 30 minutes. With moderate agitation, the reaction temperature is cooled to 20-25° C. over a minimum of 1 hour. The reaction mixture is agitated at 20-25° C. for a minimum of 1 hour. The product is filtered through a cotton terylene cloth and the filtercake rinsed with 2×9 kg purified water. The wet filtercake is transferred to a 200 L reaction vessel followed by 30.1 kg purified water, 4.6 kg 31% hydrochloric acid. The transfer lines are rinsed with 5 kg purified water. With moderate agitation, the suspension is warmed to 85-90° C. for a period of 1-3 hours. The reaction mixture is cooled to 20-25° C. and 31.0 kg acetone is added over a minimum period of 30 minutes. The suspension is agitated at 20-25° C. for a minimum of 1 hour. The product is filtered through a cotton terylene cloth and the filtercake rinsed with 2×6 kg acetone. The product is dried under a stream of nitrogen on the filter until it passes drying specifications. Once dry, the crude product (substantially pure (about or more than 95%) tin (IV) mesoporphyrin IX dichloride) is packaged. The theoretical yield for this reaction is 5.3 kg. Typically, the crude, substantially pure tin mesoporphyrin product is isolated with a yield of 4.0-4.8 kg (75-90% yield).
Step 3
An inerted 200 L reactor is charged with 1.8 kg crude, substantially pure tin mesoporphyrin, formed via Steps 1 and 2, and 31 kg WFI (water for injection) with moderate agitation at 20-25° C. The reactor is charged with 2.4 kg 28% ammonium hydroxide. The resultant solution is agitated at 20-25° C. for 30 minutes, prior to testing pH to ensure that it is greater than 9. If not, additional ammonium hydroxide is added in small portions until this pH level is achieved. To the resultant solution is charged 0.1 kg Darco KB activated carbon and 0.2 kg hyflo supercel suspended in 2.3 kg purified water. With moderate agitation, the suspension is agitated at 20-25° C. for a minimum of 30 minutes. The suspension is filtered through a sparkler filter to remove solids, leaving a filtrate. The filter cake is rinsed with 13 kg purified water. An inerted 200 L reactor is charged with 69.3 kg acetic acid and 3.1 kg 31% hydrochloric acid. With moderate agitation, under nitrogen while maintaining a temperature of 20-25° C. the filtrate is added to the acetic acid HCl solution over a minimum of 45 minutes. The resultant suspension is agitated for 15 minutes at 20-25° C. prior to testing the pH level to ensure that the final pH is about less than or equal to 1. If not, additional hydrochloric acid is added in small portions until this pH level is achieved. The suspension is then agitated at 20-25 C for a minimum of 1 hour. The product is filtered through a cotton terylene cloth and the filter cake is rinsed with 2×5 kg purified water.
With moderate agitation, at 20-25° C., an inerted 200 L reactor is charged with 31 kg purified water and 2.4 kg 28% ammonium hydroxide. The solution is then recirculated through the filtercake in order to completely dissolve all wetcake. The resultant solution is agitated at 20-25° C. for 30 minutes, prior to testing pH to ensure that it is greater than 9. If not, additional ammonium hydroxide is added in small portions until this level is achieved. To the resultant solution is charged 0.1 kg Darco KB activated carbon and 0.2 kg hyflo supercel suspended in 2.3 kg purified water. With moderate agitation, the suspension is agitated at 20-25° C. for a minimum of 30 minutes. The suspension is filtered through a sparkler filter to remove solids, leaving a filtrate. The filter cake is rinsed with 13 kg purified water. An inerted 200 L reactor is charged with 69.3 kg acetic acid and 3.1 kg 31% hydrochloric acid. With moderate agitation, under nitrogen while maintaining a temperature of 20-25° C. the filtrate is added to the acetic acid HCl solution over a minimum of 45 minutes. The resultant suspension is agitated for 15 minutes at 20-25° C. prior to testing the pH level to ensure that the final pH is about less than or equal to 1. If not, additional hydrochloric acid is added in small portions until this pH level is achieved. The suspension is then agitated at 20-25° C. for a minimum of 1 hour. The product is filtered through a cotton terylene cloth and the filter cake is rinsed with 2×5 kg purified water.
With moderate agitation, at 20-25° C., an inerted 200 L reactor is charged with 31 kg purified water and 2.4 kg 28% ammonium hydroxide. The solution is then recirculated through the filtercake in order to completely dissolve all wetcake. The resultant solution is agitated at 20-25° C. for 30 minutes, prior to testing pH to ensure that it is greater than 9. If not, additional ammonium hydroxide is added in small portions until this level is achieved. To the resultant solution is charged 0.1 kg Darco KB activated carbon and 0.2 kg hyflo supercel suspended in 2.3 kg purified water. With moderate agitation, the suspension is agitated at 20-25° C. for a minimum of 30 minutes. The suspension is filtered through a sparkler filter to remove solids, leaving a filtrate. The filter cake is rinsed with 13 kg purified water. An inerted 200 L reactor is charged with 69.3 kg acetic acid and 3.1 kg 31% hydrochloric acid. With moderate agitation, under nitrogen while maintaining a temperature of 20-25° C. the filtrate is added to the acetic acid/HCl solution over a minimum of 45 minutes. The resultant suspension is agitated for 15 minutes at 20-25° C. prior to testing the pH level to ensure that the final pH is about less than or equal to 1. If not, additional hydrochloric acid is added in small portions until this pH level is achieved. The suspension is then agitated at 20-25° C. for a minimum of 1 hour.
The resulting product is filtered through a cotton terylene cloth and the filter cake is rinsed with 2×5 kg purified water and 2×4 kg acetone. The filter cake product is dried under vacuum with a maximum oven temperature of 100° C. until it passes drying specifications. Once dry, the pharmaceutical grade pure product (tin (IV) mesoporphyrin IX dichloride or stannsopoifin) is packaged and is of pharmaceutical grade quality, as verified by analytical HPLC technique. The theoretical yield for this reaction is 1.8 kg. Typically, the final product is isolated with a yield of 1.1-1.6 kg (60-90%) and is pharmaceutical grade pure (at least about or exceeding 97%).
EXAMPLE 5
Representative Large Scale Production of Tin Mesoporphyrin IX Chloride (Tin (IV) Mesoporphyrin IX Dichloride or Stannsoporfin)
Step 1
Without agitation, a 200 L reaction vessel which has been pressure tested and inerted with nitrogen is charged with 0.6 kg of 5% palladium on carbon (50% water by weight), 6.0 kg hemin and 161.0 kg formic acid, while minimizing the exposure of the ingredients throughout this reaction to visible or ultraviolet light. The vessel is pressurized with hydrogen to 30-35 psi at 20-25° C. The reaction mixture is agitated vigorously for a minimum of 30 minutes and warmed to 85-90° C. With vigorous agitation, the reaction temperature is maintained at 85-90° C. with a hydrogen pressure of 55-65 psi for a period of 60-90 minutes. The reaction is then cooled to 45-50° C. while maintaining pressure and hydrogenation is continued for a further 24-48 hours. The reaction is cooled to 20-25° C. The reactor is depressurized and inerted (flushed) with nitrogen. The reactor is charged with a dispersion agent, such as 3.0 kg hyflo supercel and 2.3 kg of DARCO KB, suspended in 36 kg formic acid. The reaction mixture is then filtered to remove the catalyst.
The filtercake is rinsed with 122 kg formic acid. 170 L of the filtrate is transferred to a 200 L reaction vessel and cooled to 10-15° C. The reaction mixture is distilled under a reduced pressure of 20-60 mmHg, with a maximum batch temperature of 50° C., to a residual volume of 25-35 L. The remainder of the filtrate is transferred into the reactor and cooled to 10-15° C. The reaction mixture is distilled under a reduced pressure of 20-60 mmHg, with a maximum batch temperature of 50° C., to a residual volume of 25-35 L. The temperature of the reactor is cooled to 20-25° C. The reaction vessel is charged with 89.0 kg methyl tert-butyl ether over a minimum of 1 hour. Upon completion of the addition, the reaction is agitated at 20-25° C. for a minimum of 2 hours. The reaction mixture is cooled to −20 to −25° C. over a minimum of 1 hour. The reaction is agitated at −20 to −25° C. for a period of 4 hours. The suspension is filtered through a cotton terylene cloth at −20 to −25° C. The filtercake is rinsed with 2×6 kg methyl tert-butyl ether. The product is dried under vacuum with a maximum oven temperature of 60° C. until it passes drying specifications. Once dry, the product (mesoporphyrin IX formate) is packaged.
Purification of the Mesoporphyrin IX Formate
Excess metal catalyst is removed from the intermediate by charging formic acid with mesoporphyrin IX formate and a quantity of a metal scavenger such as Si-Thiol (approximately 2-10% of the yield of intermediate, based on calculation) with moderate agitation under nitrogen for 16 to 20 hours at 70-80° C. The metal scavenger and excess catalyst is then removed by reducing the temperature to 20-25° C., and then charging a filtering aid such as celite (−5%/0.3 kg) and additional formic acid (−32 kg) into the mixture. The mixture is then filtered and vacuum distilled. The concentrated filtrate is slowly added to a mixture of purified water (52 kg) and 31% hydrochloric acid (9.3 kg) (by calculation based on the quantity of dry intermediate). Gentle agitation and a temperature of 20-25° C. is maintained for a period of 2-3 hours. The resultant mesoporphyrin IX dihydrochloride in suspension is isolated by filtration and dried on the filter while passing a stream of nitrogen through the filter.
The procedure described immediately above may be repeated at least one or two more times for a total of at least 1-3 purifications. Adequate results have been obtained with one purification step.
Step 2
An inerted 200 liter reaction vessel is charged with approximately 2.8 kg of mesoporphyrin IX dihydrochloride, 3.3 kg tin chloride and 73 kilogram acetic acid. The suspension is moderately agitated at 20-25° C., for a minimum of 30 minutes. The suspension is vigorously agitated for a minimum of 30 minutes at a temperature of 20-25° C., while bubbling in a mixture of 6% oxygen in nitrogen. With vigorous agitation under nitrogen and maintaining a 6% oxygen in nitrogen purge, the reaction mixture is heated to reflux (ca 115° C.) and maintained for 24 to 26 hours.
The 6% oxygen in nitrogen purge is shut off. The reaction is cooled to 60-70° C. and approximately 28 kg of purified (de-ionized) water is added over a minimum of 30 minutes. With moderate agitation, the reaction temperature is cooled to 20-25° C. over a minimum of 30 minutes. The reaction mixture is agitated at 20-25° C. for a minimum of 1 hour. The product is filtered through a cotton terylene cloth and the filtercake rinsed with 11 kg purified water. The wet filtercake is transferred to a 200 L reaction vessel followed by 40 kg purified water, 6.6 kg 31% hydrochloric acid. The transfer lines are rinsed with 10 kg purified water. With moderate agitation, the suspension is warmed to 85-95° C. for a period of 1-2 hours. The reaction mixture is cooled to 20-25° C. The suspension is agitated at 20-25° C. for a minimum of 30 minutes. The product is filtered through a cotton terylene cloth and the filtercake rinsed with 11 kg purified water. The product is dried under a stream of nitrogen on the filter until it passes drying specifications. Once dry, the crude product (substantially pure (about or more than 95%) tin (IV) mesoporphyrin IX dichloride) is packaged. Typically, the crude, substantially pure tin mesoporphyrin dichloride product is isolated with a yield of 2.2 kg and 97% purity.
Step 3
An inerted 100 L reactor without agitation is charged with approx. 2.2 kg crude, substantially pure tin mesoporphyrin dichloride, formed via Steps 1 and 2; 0.3 kg hyflo supercel, 0.1 Kg DARCO KB, and 19 kg WFI (water for injection). With moderate agitation at the reactor is charged with 1.5 kg 28% ammonium hydroxide. The resultant solution is agitated at 20-25° C. for 1 to 2 hours, prior to testing pH to ensure that it is equal to or greater than 9. If not, additional ammonium hydroxide is added in small portions until this pH level is achieved. With moderate agitation, the suspension is agitated at 20-25° C. for a minimum of 1-2 hours. The suspension is filtered through a filter to remove solids, leaving a filtrate. The filter cake is rinsed with 7 kg WFI. An inerted 200 L reactor is charged with 58 kg acetic acid and 2.4 kg 31% hydrochloric acid. With moderate agitation, under nitrogen while maintaining a temperature of 20-25° C. the filtrate is added to the acetic acid/HCl solution over a minimum of 45 minutes. The resultant suspension is agitated for a minimum of 15 minutes at 20-25° C. prior to testing the pH level to ensure that the final pH is about less than or equal to 1. If not, additional hydrochloric acid is added in small portions until this pH level is achieved. The suspension is then agitated at 20-25 C for 1-2 hours. The product is filtered through a cotton terylene cloth and the filter cake is rinsed with 10 kg WFI.
The procedure described immediately above may be repeated at least one or two more times for a total of at least 1-3 purifications. Adequate results have been obtained with one purification step.
Without agitation, the wet filter cake and 26 kg WFI are transferred into a 200 L reactor. With moderate agitation, under nitrogen at 20-25° C., 15.5 kg of 31% HCl and 5 kg WFI are charged into the reactor. The mixture is heated to 85-90° C. and agitated for 16-18 hours. While moderately agitating the vessel contents, the temperature of the mixture is lowered to 20-25° C. and the agitation is continued for at least one hour. The reaction mixture is then filtered. The filter cake is rinsed with a mixture of 19 kg WFI and 0.7 kg 31% HCl.
The filter cake product is dried by passing a stream of nitrogen through the filter and applying heat to the filter apparatus until it passes drying specifications. Once dry, the product (tin (IV) mesoporphyrin IX dichloride or stannsoporfin) is packaged and is of pharmaceutical grade quality and purity, as verified by analytical HPLC technique. Typically, the final product is isolated with a yield of 1.2 kg with a purity exceeding 97%).
While foregoing is directed to the preferred embodiment of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow. | A method of preparing metal mesoporphyrin halide compounds is described. The metal mesoporphyrin halide compound may be formed by forming a novel mesoporphyrin IX intermediate compound and then converting the mesoporphyrin IX intermediate to the metal mesoporphyrin halide through metal insertion. The novel intermediate compound may be formed by a catalytic hydrogenation of hemin in acid and subsequent recovery. | 2 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation of Ser. No. 12/892,009, entitled, “Uniform Equipment Mounting System,” filed on Sep. 28, 2010, which is a continuation-in-part of International Patent Application No. PCT/US2009/038851, entitled, “Uniform Equipment Mounting System,” filed on Mar. 30, 2009, which claims priority from U.S. Provisional Application No. 61/040,542, entitled, “Uniform Equipment Mounting System,” filed on Mar. 28, 2008; U.S. Provisional Application No. 61/040,924, entitled, “Uniform Equipment Mounting System,” filed on Mar. 31, 2008; U.S. Provisional Application No. 61/157,118, entitled, “Uniform Equipment Mounting System External Bearing With Integrated Insertion Guide,” filed on Mar. 3, 2009; and U.S. Provisional Application No. 61/157,113, entitled, “Uniform Equipment Mounting System Simplified Mechanism With Safety Stop,” filed on Mar. 3, 2009, the contents of all which are incorporated herein as if set forth in full.
FIELD OF INVENTION
[0002] The present invention relates generally to mounting equipment such as electronic data processing (EDP) equipment in racks and, in particular, to a uniform mounting system that can be used in mounting a variety of EDP equipment having differing widths, depths and mounting structure.
BACKGROUND OF THE INVENTION
[0003] EDP equipment is deployed in various environments including residential and business environments. In many cases, multiple pieces of equipment are mounted in a support structure such as a two-post or four-post rack or cabinet, all of which are generally referenced herein as a “rack.” In the case of data centers, multiple racks may be configured side by side in rows. It is not uncommon today for such data centers to occupy tens of thousands of square feet.
[0004] There is limited standardization of the dimensions of the equipment and the racks, and even less standardization of the mounting structure for mounting the equipment to the racks. In this regard, the NEMA cabinet and rack standard defines a horizontal spacing of the equipment mounting flanges of a rack, a width of the main body of the inserted equipment, a vertical spacing unit (equipment may occupy a multiple of this unit), and a vertical spacing of equipment mounting holes in the vertical support structure of the rack. These standards are more specifically set forth in NEMA publications.
[0005] There are no other accepted standard dimensions for racks and equipment. For example, the depth of the equipment to be mounted is not dictated by the standard. In addition, the width of the equipment can vary, and the hardware required for mounting is not standardized.
[0006] Moreover, the functionality of the equipment mounting hardware used in NEMA standard and other racks varies. In this regard, there are generally three ways that equipment is mounted in racks. First, the equipment can simply be placed on shelves, which are mounted in the racks. Second, the equipment can be directly mounted to the racks by way of static rack mounting adapters that attach to vertical mounting rails that are either fastened to or are part of the cabinet. Finally, the equipment can be mounted to the rack via rail assemblies that fasten to the vertical mounting rails and allow the equipment to be moved forwardly and rearwardly relative to the rack for improved access.
[0007] Many different types of equipment are available from many different manufacturers. Because of the limited standardization noted above, this equipment varies substantially with regard to width, depth, height and rack mounting hardware. The result of this state of affairs is that each manufacturer is responsible for supplying rack mounting hardware that is compatible with the NEMA (or other) standard of the equipment rack. This results in considerable difficulty in installing and accessing the equipment, especially in the case of rack rails because how they attach to the equipment, how far they slide out, how they lock and release, how one removes a piece of equipment from the rack, etc., all vary. This is frustrating to personnel responsible for the equipment, and it is a significant impediment to reconfiguring the layout of equipment and racks as may be desired. For example, in the data center environment, it may be desired to reconfigure racks and equipment for improved efficiency or performance or to accommodate customer changes. However, the difficulty of removing and remounting equipment sometimes weights upon such decisions.
[0008] In some cases, the problems caused go beyond inconvenience. Installing or removing certain equipment from a rack may force the removal of adjacent equipment to complete the task. This can require down time, which is difficult to schedule, and it is potentially disruptive and expensive.
[0009] The lack of standardization of mounting equipment also results in significant capital expenditures. In particular, it is often necessary to purchase specially designed mounting accessories, such as a rail kit, in connection with the purchase of a piece of equipment. This can be a significant expenditure, particularly in the case of data centers that utilize a large volume of equipment. Moreover, as equipment is added and other equipment is removed and replaced, a large volume of such mounting hardware may be accumulated. Because this mounting hardware is often specially designed for a particular manufacturer and/or a particular piece of equipment, it is difficult to efficiently collect and reuse such mounting hardware. Equipment manufacturers also often intentionally change the design of each rail kit for each new generation of equipment, forcing the purchase of new rail kits which improves their profits. The result is that data centers often accumulate a large volume of mounting hardware, representing a significant capital expenditure, which the data center operator does not know whether to retain.
SUMMARY OF THE INVENTION
[0010] The present invention relates generally to mounting equipment such as electronic data processing (EDP) equipment in racks and, in particular, to a uniform mounting system that can be used in mounting a variety of EDP equipment having differing widths, depths and mounting structure. Initially, it should be appreciated that although terms that describe certain orientations (e.g., vertical, horizontal, or the like) are used herein, any suitable reference axes may be used that are appropriate for a particular application. For the purpose of illustration and not limitation, the embodiments described herein show uniform mounting systems that are operative to mount EDP equipment in a vertical stack, although other orientations may also be provided by embodiments of the present invention. The present invention relates to a mounting system for electronic equipment such as equipment mounted in a two-post or four-post rack in a data center environment. The invention standardizes how equipment is mounted to and positioned in the rack, yet is totally compatible with NEMA or other dimensional standards such as NEMA. The mounting system can be added as an option to suitable existing two or four-post racks or integrated as a part of a two or four-post rack design. It will work with many current standard NEMA dimension two or four-post racks (each variant would have similar features and functions, but different dimensions) or can be used with other standards or custom dimension two or four-post racks. The uniform nature of how the mounting system is designed and functions yields many benefits as will be explained below.
[0011] One or more embodiments of the present invention provides a set of structures that includes a number of vertical support posts that have a number of horizontal support rails attached to them at any desired interval (at 1 U=1.75″ for example) or pattern of intervals. The structures can be made up of sub-structures in any modulus that may be optimal, for example, in halves, thirds, etc. This may allow for various combinations of sub-structures to be joined together to form a full structure and for the full structure to have different numbers of horizontal rails as needed for different height racks. A pair of the structures may reside on each side of the rack (or may be integrated into the sides of the rack instead of attached to the sides of the rack) to form an equipment mounting assembly. The equipment mounting assemblies allow equipment in the rack to be mounted from the front or the back. In accordance with one aspect of the present invention, a rack can be designed to have vertical sections that match the heights of sub-modules of the assemblies and thereby integrate them into the rack. The various combinations of sub-modules may be combined with the various combinations of rack vertical sections to form racks of any heights that incorporate the mounting system. A possible feature of the design is that this can be done without sacrificing any 1 U mounting positions. A possible use of this capability is described in PCT Application No. PCT/US09/38427 wherein the possibility of constructing modular plug strips for power distribution, modular USB/KVM strips for Universal Serial Bus/Keyboard Video Mouse connections and modular network distribution strips is described. The modular power, USB/KVM and network distribution strips could be constructed in vertical modulus that match the height of the vertical rack sections and facilitate mounting them in the modular rack design.
[0012] In accordance with one aspect of the present invention, the assemblies allow different pieces of equipment to be mounted at different horizontal offsets in relation to a front or rear face of a support structure (such as a rack). The assemblies are dimensioned for supporting multiple pieces of electronic equipment in a vertically stacked configuration. The support structure has a front end defining one or more openings where front surfaces of the electronic equipment are disposed adjacent to the one or more openings. For example, the National Electrical Manufacturing Association (NEMA) cabinet and rack standard defines the spacing of conventional vertical mounting flanges for defining this front opening. The system further includes first mounting structure for mounting a first piece of equipment in a fixed position in relation to the support structure so that a first front surface of the first piece of equipment has a first horizontal offset in relation to the front end of the support structure, and a second mounting structure for mounting a second piece of equipment in a fixed position in relation to the support structure so that a second front surface of the second piece of equipment has a second horizontal offset, different than the first horizontal offset, in relation to the front end of the support structure. The system may include additional positioning structures so that each piece of equipment in the support structure can have an individually selected horizontal offset. In this manner, equipment having different depths can be accommodated or differing horizontal offsets can be supported for any reason desired by a user.
[0013] In accordance with a further aspect of the present invention, a method is provided for changing a horizontal offset of a piece of equipment with respect to a support structure. The method involves providing a support structure having a rail assembly and providing a piece of electronic equipment. The piece of electronic equipment is then secured to a mounting structure. The method further involves inserting the piece of electronic equipment into the support structure by slidably engaging the mounting structure and the rail assembly. A horizontal position of the piece of electronic equipment is then fixed in relation to the support structure at a first location. The method further involves sliding the mounting structure in relation to the rail assembly so that the piece of electronic equipment is disposed at a second location in relation to the support structure and fixing the electronic equipment at the second location. The position of the electronic equipment can be fixed at a number of locations (e.g., discrete locations) so as to provide a range of possible horizontal offsets.
[0014] In accordance with a still further aspect of the present invention, a method is provided for use in moving electronic equipment. The method involves providing a support structure having a number of vertically spaced rail assemblies and having a piece of electronic equipment. The piece of electronic equipment may be secured to a mounting structure. The piece of electronic equipment can then be inserted into the support structure by slidably engaging the mounting structure and a first one of the rail assemblies. Conversely, the piece of electronic equipment can be removed from the support structure by slidably disengaging the mounting structure and the first rail assembly. The piece of electronic equipment can then be re-inserted into the support structure by slidably engaging the mounting structure and a second one of the rail assemblies. In this manner, the electronic equipment can be moved to a different vertical location within the support structure without detaching the equipment from the mounting structure and without the need for tools. Similarly, the equipment can be moved from one support structure to another support structure in accordance with the present invention. In accordance with one aspect of the present invention, the assemblies allow for NEMA standard (or other desired standard or custom) mounting rails to be mounted horizontally (either front to back on the sides of the rack or side-to-side across the rack) in the assembly. This allows NEMA standard equipment that can benefit from such an arrangement, for example patch panels to be mounted side-by-side vertically in the rack at a given vertical height, but still be able to be removed from the rack.
[0015] In accordance with one aspect of the present invention, the assemblies allow for equipment to be mounted horizontally in the rack but be wider than the NEMA standard. This is possible because the assemblies on each side of the rack are spaced wider than the NEMA standard so that a variety of equipment widths that are at or below the maximum width that is compatible with the NEMA standard unitary vertical mounting rails. The segmented vertical rail design allows equipment to use the space between the maximum NEMA width and the location of the slider on each side of the rack. This is the case because the equipment can be designed to mount to the sliders in such a way that it does not have to pass between a NEMA defined opening between the unitary vertical mounting rails.
[0016] In another aspect of the invention, the horizontal support rails can have an integrated uniform latching mechanism on one or both ends that allow a user to adjust and secure the position of one or more adjustable sliders on the horizontal rail. The uniform nature of the latching mechanism is a feature that allows any equipment with integrated sliders or other mechanisms to be freely moved between the horizontal rails in the racks or between multiple racks. The slider can be a separate piece or integrated into the design of equipment or accessories that are designed to mount into the assembly by sliding onto the horizontal rails. The adjustability of the horizontal sliders allows for mounting of a piece of equipment attached to the slider at a selected horizontal offset position in relation to a front end of a support structure such as a rack and allows different pieces of equipment to be supported at different horizontal offsets in relation to the front end of the mounting structure. In another aspect of the invention, the integrated uniform latching mechanism can be implemented to be uniform in how it works, how it is operated (e.g., same user interface for every slider) and can be very convenient to use. Since all the slider interfaces to the horizontal support rail are uniform and attach to the rack in the same way, the release mechanism can be designed to be the same for all sliders, regardless of their other details.
[0017] The release mechanism may also release, one, many or all of a set of sliders. It is practical to design a release mechanism this way because of the uniform design of the slider latch mechanism.
[0018] In another aspect of the invention, the release mechanism can be made as follows to be easily accessible to the user. Standard cabinets often have equipment-mounting flanges that are attached to the structural supports of the equipment cabinet such that there is little or no gap between the equipment mounting flanges and the support. The result of this fact is that most equipment vendors build rack mount rail systems that require the user to reach into the cabinet and press a button or toggle a lever to release the equipment from a locked position. This is very difficult in a fully loaded rack. The user must reach around the side of the equipment mounting flange and attached support and activate the release button or lever. In some cases, it is impossible to do w/o removing the equipment that is mounted above or below the equipment the user wishes to remove. If this is the case, the data center manager must leave a space above or below the affected equipment thus wasting that rack space.
[0019] If the mounting system is designed as an option to an existing cabinet, there can be clearance to place a uniform release mechanism (button, lever, etc.) that is located between the edge of the front opening of the rack and the back (side away from where the equipment attaches to the slider). This is because the slider support assemblies and associated sliders attach to the cabinet structure in a way that this space is available for a uniform release mechanism to occupy. This puts the release mechanism on the front and back of the cabinet in an easy to use location where it is visible and simple to see how to use it (the user interface, or UI). In addition, the release mechanism latch lever is designed to be easily installed or removed from horizontal rail assemblies as needed. This is useful in minimizing the number of latch assemblies required, thus lowering costs.
[0020] If a system is designed to be integrated into the cabinet, then the cabinet can easily be designed to place the release mechanism in the front and/or back of the cabinet, in an easy to use location. This is only practical due to the uniform nature of the system, since the sliders have standardized attachment and latching mechanisms and can be designed to be released in a uniform manner.
[0021] In accordance with another aspect of the invention, the adjustable sliders can be made in different lengths and used in pairs on each side (e.g., two sliders on each rail) of a piece of equipment to mount the equipment to the pair of assemblies on the side of the rack. This “split-slider” feature allows equipment of different sizes to be mounted with a minimum of different length sliders. In other words, the sliders may work in dual pairs, one pair per side per 1 U (note that equipment that is relatively short in depth may be mounted using only two sliders).
[0022] In accordance with another aspect of the invention, the adjustable sliders can be made as compound sliders, e.g., a slider including two or more sections that can telescope to a length that is greater than any one of their sections. One half of the compound assembly could be assembled as part of the horizontal rail, or both or multiple parts of the compound slider can be assembled in the slider section only.
[0023] In accordance with another aspect of the invention, equipment that is large and heavy, or shelves, trays and accessories, etc. intended to support high loads (especially loads that may be higher than the load rating of a single pair of sliders in 1 U of rack space, or loads that may be generated by dynamic forces, such as when a rack is mounted in a mobile environment, such as a truck, ship or airplane, etc. or an unstable environment, such as an earthquake zone) can be attached to multiple sliders to divide the load over the multiple sliders and horizontal rails when the equipment, shelves, trays or accessories, etc. are inserted into the assembly and engage multiple horizontal rails. In the case of existing equipment, trays, shelves, etc., this can be done by attaching multiple sliders per side to the equipment and then engaging multiple horizontal rails when slidably inserting the equipment into the assembly. Alternatively, it can be done by using mounting adapters that engage more than 1 U of mounting holes, or using multiple mounting adapters. Alternatively, for equipment with integrated sliders, trays, accessories, etc. multiple sliders per side that will engage multiple horizontal rails per side may be provided.
[0024] In accordance with another aspect of the invention, the sliders can be designed to mount in either orientation onto the horizontal sliders. This allows equipment to be put into the rack from either the front or back. It also allows the equipment to be removed from the rack and reversed 180 degrees and remounted in the rack. In this regard, it may be useful to be able to access either the front or back of the equipment from either the front or back of the rack.
[0025] In accordance with another aspect of the invention, a universal mounting adapter can be provided to attach equipment to a slider or one or more pairs of sliders. The universal mounting adapter may include an equipment standoff that attaches to the slider and is in the shape of an “L” where the bottom of the “L” has a pattern of parallel-aligned angled slots. Further, the universal mounting adapter may be supplied as a universal or equipment specific mounting adapter that attaches to the side (or top, bottom, front, or rear) of the equipment being mounted. If the mounting adapter is equipment specific, it can be designed with one or more holes (or other equipment specific attachment arrangements such as slots, pins, .etc) to mate to one or more specific models of equipment. It may be made in the shape of an “L” where the bottom of the “L” has a pattern of parallel-aligned angled slots. The bottom of the “L” of the equipment standoff is attached to the bottom of the “L” of the equipment mounting adapter so that together they form a “U” where the width of the “U” is adjustable. This is facilitated by the arrangement of the parallel angled slots in both or either of the equipment standoff and/or the equipment mounting adapter. The slots may be laid out according to a logarithmically based spacing that insures that one of the slots in the equipment standoff will always align with a slot on the universal equipment mount. This allows a fastener such as a bolt and nut to be used to secure the equipment standoff and the equipment mounting adapter together. This universal mounting adapter can therefore be used to accommodate a variety of equipment with different hardware (or none) for attaching rail kits to the equipment. It also can accommodate equipment of different lengths, widths and depths. The mounting adapters can be used in whatever number is needed to mount the equipment.
[0026] In accordance with another aspect of the invention, a mounting adapter that is specific to one or several models of equipment can be provided to attach equipment to a slider or one or more pairs of sliders. The model specific mounting adapter can be formed in the shape of a
[0027] “U” where one side of the “U” attaches to the slider, and the other side of the “U” is configured to attach to the equipment. The width of the mounting adapter may be specific to the model or models of equipment being mounted. The mounting adapters can be used in whatever number is needed to mount the equipment.
[0028] In accordance with another aspect of the present invention, a mounting system includes a segmented vertical mount rail. Conventionally, electronic equipment has been mounted to a pair of vertical mount rails at the front of a support structure, either directly, using right angle brackets, or via a rail kit. The present inventors have recognized that this unitary rail design limits mounting functionality. Accordingly, the inventive system includes a support structure, dimensioned for supporting multiple pieces of electronic equipment in a vertically stacked configuration and a vertically segmented rail assembly interconnected to the support structure. The vertically segmented rail assembly includes a first rail segment subassembly for mounting a first piece of electronic equipment and a second rail segment subassembly, vertically offset from the first rail segment subassembly for mounting a second piece of electronic equipment. The first rail segment subassembly is horizontally moveable in relation to the second rail segment subassembly. For example, one or both of the first and second rail segment subassemblies may be independently moveable along a front-to-back axis horizontal element of the support structure.
[0029] The invention provides the vertical segmented mounting rail with NEMA standard mounting holes (or other desired standard or custom dimension or attachment hardware) that can be attached to an end or ends of the adjustable slider to provide compatibility with NEMA standard mounting adapters, accessories (trays, shelves, cable management accessories, etc.) and rail mount kits for conventional NEMA racks. As noted earlier, the NEMA standard specifies the hole locations in vertical mounting rails but does not specify the fastener type to be used with the holes. Therefore the vertical segmented mounting rail can be made with any needed fastener types (such as 12/24 threads, 10/32 threads, or ⅜″ square holes for cage nuts) or any desired custom hardware or other standard hardware. That is, any vertical, segmented mounting rails with varying fastener types may be intermixed in the same rack assembly as needed. It should be noted that any equipment, shelf, accessory, etc. thus attached to a segmented vertical mounting adapter that is mounted to a slider is thereby made horizontally adjustable and can be moved from one (or more than one if the equipment is more than 1 U high and attaches to several vertical segmented mounting rails) horizontal rail to another in the same rack or a different rack without tools.
[0030] An optional embodiment of the vertical segmented mounting adapter may include a vertical or horizontal hinge. This allows equipment that is mounted via the vertical segmented mounting adapter to be pivoted to gain access for servicing or other needs. An alternative embodiment and usage of the vertical segmented mounting rail is to attach it directly to a horizontal support element of an assembly that is adapted for that purpose. In such an embodiment, the horizontal support rails may be replaced by a simpler and/or lower cost mechanism, such as a horizontal slot. This may allow the vertically segmented mounting rail to be attached to the assembly and to be adjusted in its horizontal offset, but may dispense with the expense of a horizontal rail, latching mechanism and adjustable slider. This embodiment may be suitable for many applications.
[0031] In accordance with another aspect of the invention, a lock or other security mechanism can be incorporated into the structure of the assembly to prevent the movement and/or removal of adjustable sliders (and the equipment or accessories attached to them) from the rack. The lock can engage one, some, or all of the sliders disposed on the horizontal rails of the assembly.
[0032] In accordance with another aspect of the invention, a lock can be incorporated into the adjustable slider and/or the adjustable slider with attached vertical segmented mounting rail to prevent the movement and/or removal of adjustable sliders (and the equipment or accessories attached to them) from the rack.
[0033] According to another aspect of the present invention, an apparatus is provided for use in mounting a piece of equipment into an equipment rack. The piece of equipment is pre-mounted onto a slider mechanism as discussed above. The noted apparatus includes a guide structure for guiding the sliders onto the rails and mounting structure for mounting the guide structure onto the rack such that the guide structure is positioned to guide the sliders into an engaged relationship with the support rails. In this regard, the guide structure preferably extends forwardly beyond a forward end of the support rails. In addition, the guide structure may be tapered at a front end thereof to provide clearance between vertically adjacent guide structures so as to facilitate placement of a slider mechanism onto the desired guide structure. A corresponding method involves providing a guide structure mounted on the rack, disposing a rearward portion of a slider mechanism on the guide structure and rearwardly advancing the sliders so that a rearward portion of the slider mechanism engages a forward portion of the support rails, and progressively rearwardly advancing the sliders in relation to support rails to a fully engaged position.
[0034] In accordance with another aspect of the present invention, an apparatus is provided for enhancing the load bearing rating of an equipment rack. The rack may include support rails that engage slider mechanisms as described above. The apparatus includes a support bearing, external to the support rails, for supporting at least a portion of a load of the piece of equipment and allowing for sliding movement of the slider mechanism in relation to the support rail, and mounting structure for mounting the support bearing on the rack in relation to the support rail such that support for the load of the piece of equipment is shared as between the support rails and support bearing for at least one position of the slider with respect to support rails. Preferably, the support bearings are dimensioned and positioned such that, when slider mechanisms are placed on each of the rails within a rack, the support bearing is in contact with or closely spaced in relation to vertically adjacent slider mechanisms. In this manner, the load rating of the rack is enhanced as may be desired for certain environments such as where the rack is subject to acceleration or heavy equipment is utilized in connection with the rack.
[0035] In accordance with a still further aspect of the present invention, a safety stop mechanism is provided for use in connection with slidably mounted equipment of a rack. The apparatus includes a slider mechanism mounted to the piece of equipment, a support rail assembly for receiving the slider mechanism, and a locking mechanism for selectively locking the slider mechanism on the support rail assembly. The locking mechanism is movable between the first position where the slider mechanism can be fully removed from the support rail assembly and a second position where a range of motion of the slider mechanism with respect to the support rail assembly is limited. In one implementation, the locking mechanism is operative for preventing accidental removal of the slider mechanism from the support rail assembly and is also operative to allow selection of the desired offset configuration of a piece of equipment with respect to the rack.
[0036] In accordance with a further aspect of the present invention, a mounting fixture that is separate from the rack and can be located in a suitable location such as on a table or roll-around cart is provided for mounting slider assemblies to a piece of equipment or shelves, trays, accessories, etc. This may simplify and increase safety in the workplace since the actions associated with mounting the adapters and sliders can be performed at a convenient height on a suitable and secure surface, where access to the hardware is easy and tools may be easily used. It is noted that this is in contrast to the conventional methodology where rack mounting adapters or rail kits require the user to attach components to the rack which may already be full of equipment and have very poor lighting and access for use of hands and/or tools. As noted above, the present invention allows a slider assembly to be pre-mounted to a piece of equipment. The slider assembly with mounted equipment can then be taken to a rack where the equipment is inserted on to support rails at the desired location. The noted fixture facilitates this functionality by enabling convenient mounting of the slider assembly to the equipment. In this regard, the fixture includes a support surface for supporting the equipment in defined spatial relationship to rail mounts. The rail mounts are spaced by a distance matching the spacing of rails in the target rack. The fixture can be used by placing a piece of equipment to be mounted on the support surface and inserting slider assemblies on the rail mounts. Mounting hardware can then be applied to the equipment and slider assembly to interconnect the equipment to the slider assembly. In one implementation, an elevator mechanism is associated with the support surface to allow vertical movement of the support surface in increments matching the vertical spacing of support rails in the target rack. In this manner, mounting of multiple u equipment is facilitated by conveniently allowing multiple sliders to be attached to each side of the equipment.
BRIEF DESCRIPTION OF THE DRAWINGS
[0037] For a more complete understanding of the present invention and further advantages thereof, reference is now made to the following detailed description taken in conjunction with the drawings in which:
[0038] FIGS. 1 and 2 illustrate perspective views of a rack system in accordance with the present invention;
[0039] FIG. 3 is a cut-away perspective view showing rail and slider assemblies of the system of FIG. 1 ;
[0040] FIGS. 4A-4B are perspective views showing alternative equipment mounting adapters for use in the system of FIG. 1 ;
[0041] FIG. 5 is an exploded view showing a safety stop mechanism for use in the system of FIG. 1 ;
[0042] FIGS. 6 and 7 illustrate operation of the safety stop mechanism of FIG. 5 ;
[0043] FIGS. 8-10 illustrate an optional external bearing and insertion guide system for use in the system of FIG. 1 ;
[0044] FIGS. 11A-11C illustrate an alternative safety stop mechanism in accordance with the present invention; and
[0045] FIGS. 12A-12B are perspective views showing an assembly fixture in accordance with the present invention.
[0046] FIGS. 13A and 13B show perspective and side views of a set of rail assemblies that include rail portions which include mechanical ramps.
[0047] FIGS. 14A and 14B show side and perspective views of a removable insertion guide that may be operative to assist a user to insert equipment into a rack.
DETAILED DESCRIPTION
[0048] In the following description, the invention is set forth in the context of a specific rack system configuration for use in a data center or similar environment for mounting EDP equipment. The invention has particular advantages for this environment due to the large volume of equipment, the variety of equipment and the likelihood of periodic reconfiguration of equipment and rack layout in such environments. However, it will be appreciated that various aspects of the invention are more broadly applicable to other equipment mounting environments and in connection with other types of equipment. Accordingly, the following description should be understood as illustrating the invention and not by way of limitation.
[0049] Referring to FIG. 1 , a perspective view of a rack 100 including a uniform mounting system 101 in accordance with the present invention is shown. Additional details of the rack 100 and configurations are shown in FIGS. 2 and 3 . It will be appreciated that the present invention can be utilized in connection with a wide variety of rack configurations including two- and four-post racks, open racks and enclosed cabinets or any other suitable configuration. In the illustrated embodiment, the rack 100 includes four corner posts 104 and an enclosure structure 102 . The rack 100 may include additional structure elements such as bottom and top surfaces and braces that are not labeled in FIG. 1 . The illustrated rack 100 further includes a front opening 108 through which equipment can be accessed and can be inserted into and removed from the rack 100 . In some cases, a front door may be provided to enclose the opening 108 though this may interfere with certain equipment offset configurations, as will be understood from the description below. The back side of the cabinet 100 opposite the front opening 108 may be open or may include an access door. In this regard, it is typically desired to be able to access the rear side of the mounted equipment for servicing. Though not shown, it should be appreciated that fans or other cooling devices may be provided in connection with the rack 100 . For example, components of such a cooling system may be mounted in a front and/or rear door of the cabinet 100 .
[0050] The illustrated rack 100 further includes a number of rail and slider assemblies 112 , as will be described in more detail below. As shown in FIG. 1 , these rail assemblies are vertically distributed across the height of the rack 100 . In the illustrated embodiment, the vertical separation between adjacent rack and slider assemblies 112 is approximately 1 u. It should be appreciated that larger and heavier equipment may occupy more than 1 u of rack space. Accordingly, in such cases, such equipment may be mounted to multiple ones of the rail and slider assemblies 112 , thereby supporting the equipment by splitting the load over multiple rail and slider assemblies 112 .
[0051] The rail and slider assemblies 112 are mounted to the rack 100 via side support posts 110 . In the illustrated embodiment, two side posts 110 are provided on each side of the rack 100 , though the number and spacing of the posts 110 can vary. The various elements of the rack 100 are manufactured from materials and are otherwise engineered to support the weight of equipment mounted and rack and to otherwise endure in a data center environment. Typically, the rack 100 may be manufactured from steel with appropriate thickness and structural reinforcement for this environment, although other materials such as aluminum can be used.
[0052] As noted above, the uniform rack mounting system 101 accommodates a variety of equipment. This includes options to mount equipment of varying widths. For example the uniform rack system can be adapted to mount equipment conforming to the 19″ NEMA standard width (the most common) or a different option can be adapted to mount equipment conforming to the 23″ NEMA standard width. Further, in the 23″ width option, 19″ NEMA standard width equipment can be accommodated in the same 23″ width rack. Mounting adapters for accommodating such variations will be described in more detail below. In this regard, the rail and slider assemblies 112 disposed on opposite sides of the rack 100 are separated by a distance that is suitable to accommodate such equipment and allow a range of adjustment via the mounting adapter as described below. To accommodate varying equipment depths, the rail and slider assemblies allow for mounting of equipment at varying offsets. Such offsets relate to the relative positions of the rack front surface 114 in relation to the mounting flanges 116 of the rail and slider assemblies 112 . The vertically segmented mounting flanges 116 typically attach directly to the front surface of the mounted equipment and therefore define the position of the front surface of the equipment. In this regard, the rail and slider assemblies 112 allow equipment to be mounted with a positive offset, a neutral offset or a negative. Positive offset refers to configurations where, when equipment is mounted, the associated mounting flanges 116 are disposed forwardly of the front surface 114 of the rack 100 . In negative offset configurations, the relevant mounting flanges 116 are disposed rearwardly of the front surface 114 . In neutral configurations, the mounting flanges 116 are substantially flush with the front surface 114 .
[0053] FIG. 2 shows varying offset configurations in this regard. The rail and slider assemblies 112 have a telescoping arrangement that accommodates such varying offsets. In addition, the rail and slider assemblies 112 may be manufactured in different lengths to further accommodate such variations in offset as well as to accommodate a desired range of forward and rearward sliding movement of the equipment in relation to the rack 100 so as to accommodate servicing as well as removal and insertion of the equipment relative to the rack 100 through either a front opening 108 or rear opening of the rack 100 . Such sliding of the equipment through a rear opening of the rack is a unique feature of the present invention. The variable offset capability is also a unique feature of the invention.
[0054] Conventionally, racks have included a continuous vertical mounting rail on each side of the front and/or back of the rack. The front surface of equipment was typically directly mounted to this rail. In the illustrated rack 100 , equipment is mounted to the mounting flanges 116 that effectively define a segmented mounting rail. That is, each mounting flange 116 is associated with one of the rail and slider assemblies 112 and can be independently moved in relation to the front-to-back depth axis of the rack 100 . This accommodates the varying offsets as shown in FIG. 2 . In addition, this allows equipment to be slideably moved forwardly and rearwardly relative to the rack 100 , and allows equipment to be inserted into the rack 100 and removed therefrom while the equipment remains mounted to the mounting flanges 116 .
[0055] The illustrated rack 100 also accommodates variations in mounting structure (e.g., the size and spacing of threaded bolt holes). As noted above, the front surface of equipment is often mounted directly to the rack. In conventional racks, the front surface of the equipment may be bolted to the continuous vertical mounting rail. In the illustrated rack 100 , the equipment is mounted to the mounting flanges 116 . Unfortunately, the hardware required for such mounting is not standardized. In particular, different equipment may require different types of bolts and different spacing of the openings for receiving the bolts. In the illustrated embodiment, the mounting flanges 116 can be adapted to accommodate these variations. In this regard, the mounting flanges 116 may include an array of openings to accommodate the most common configuration in this regard, or the mounting flanges 116 may be interchanged depending on the equipment to be mounted. In the illustrated embodiment, different ones of the mounting flanges 116 are interchangeable and have different configurations in this regard, e.g., differently shaped (e.g., round or square) openings and different spacings.
[0056] The illustrated rack 100 also accommodates equipment of different widths in relation to a side-to-side dimension of the rack 100 . It will be appreciated that equipment is often mounted to the rack not only by way of the front surface of the equipment but also in relation to the side surfaces of the equipment. This is particularly useful in connection with equipment mounted so as to slide in and out of the rack. In this regard, equipment typically includes mounting structure on the equipment sides that, in the past, has been used to mount the equipment to corresponding structure of a specially designed rail kit. In the illustrated embodiment, the same mounting structure of the equipment can be used to mount the equipment to the structure of the rail and slider assemblies 112 , as will be discussed in more detail below. Again, the existing mounting structure varies from case to case. In addition, different pieces of equipment can have different widths.
[0057] Accordingly, as shown in FIG. 4A , universal equipment mounting adapters 400 can be used to mount the equipment to the rail and slider assemblies 112 . Generally, the mounting adapter assembly 400 can be reconfigured to accommodate equipment of different widths and includes mounting structure for mating to different types of equipment. The illustrated assembly 400 includes first and second L-shaped mounting adapters 402 , 404 . One of the brackets 402 or 404 is bolted to a piece of equipment by way of openings 406 formed on a base thereof, and the other mounting adapter 402 or 404 is attached to a slider of the rail and slider assembly 112 by installing a bolt through the openings 406 . In this regard, an array of openings 406 may be provided to accommodate different mounting configurations of different equipment, or custom mounting adapters may be provided for different types of equipment. The illustrated brackets 402 and 404 further include an array of openings 408 distributed along the length of the side portions of the brackets 402 , 404 . It will be appreciated that the two brackets 402 , 404 are interconnected by bolts or the like to connect the equipment to the rail and slider assembly via the vertical segmented mounting flanges. The array of openings 408 allows for appropriate selection of the overall length of the interconnected brackets 402 , 404 so as to accommodate equipment of varying widths.
[0058] FIG. 4B shows an alternate configuration of a mounting adapter assembly 409 . In this case, the assembly 409 includes a slider standoff 410 for attachment to the slider and two different equipment mounting adapters 412 and 414 for attachment to the equipment. Once the slider standoff 410 is attached to the slider and the equipment mounting adapter 412 or 414 is attached to the equipment, the slider standoff base 411 can be bolted to the equipment mounting adapter base 413 and 415 . The diagonal arrangement of the slots on the bases 411 , 413 and 415 ensures that the slots can be aligned to allow bolting and also allows significant adjustment of the width of the resulting bracket. The vertical leg 417 of adapter 412 has a variety of slots to match up with the mounting structure of a variety of equipment for bolting. The teardrop shaped openings of the vertical let 419 of standoff 415 can receive the heads of mushroom shaped mounting pins, provided on some equipment such that the heads cannot easily become dislodged from the opposing teardrop openings. That is, the illustrated bracket assembly works in connection with a variety of equipment so that the need for custom bracket assemblies for individual pieces or types of equipment are reduced.
[0059] FIGS. 5-7 show details of a safety stop assembly 500 used in connection with the rail and slider assembly. The safety stop assembly 500 performs a number of functions. First, as noted above, the rail and slider assembly can be configured to accommodate a variety of different offset configurations. In this regard, the safety stop assembly 500 can lock the relative positions of a horizontal rail 502 and a slider 504 to define the desired offset configuration. As shown, the rail 502 includes a base area 501 for mounting to the side posts 110 (See FIG. 1 ) and flanges 503 . The slider 504 includes flanges 505 that engage the flanges 503 of the rail 502 so that the slider 504 can slide forwardly and rearwardly on the rails 502 . The components of the safety stop assembly 500 may be symmetrical, such that each part may be used on either side (e.g., right or left) of the assembly 500 . This feature may reduce manufacturing costs as well as simplify assembly of the system in the field by a user.
[0060] The safety stop assembly 500 functions to limit movement of the slider 504 in relation to the rail 502 . The assembly 500 includes an actuator 506 and a spring 508 with retention puck 512 . A screw 514 extends through a slotted opening 516 of actuator 506 and opening 518 of spring 508 into threaded stud 510 mounted on rail 502 so as to connect the actuator 506 and spring 508 to the rail. The puck 512 is dimensioned to drop into any one of the openings 520 on the slider 504 so as to substantially lock the relative positions of the rail 502 (and, in turn, the rack) and the slider 504 at the position defined by any one of the openings 520 . In this matter, any desired equipment offset configuration can be locked in. Although a round puck 512 and round openings 520 are shown, any cooperating geometry (e.g., matching shapes) could be employed in this regard.
[0061] It will thus be appreciated that relative motion between the rail 502 and slider 504 is allowed when the puck 512 is withdrawn from the opening 520 and is substantially prevented when the puck 512 is engaged in one of the openings 520 . The illustrated actuator 506 interacts with the spring 508 in two different ways to actuate movement of the puck 512 into and out of the opening 520 . First, the latch handle 522 can be moved between locked and unlocked positions to selectively allow movement of the slider 504 and attached equipment. The actuator 506 and spring 508 are configured in relation to the rail 502 and slider 504 so that, for a particular screw position in the opening 516 , as will be discussed momentarily, the puck is biased by the spring 508 against the slider 504 . Accordingly, the slider 504 will move only a short distance in relation to rail 502 until the puck 512 finds an opening 520 . An offset configuration is then locked in place. The user can fine-tune this offset configuration by moving the latch handle 522 to the unlocked position and sliding the slider 504 and equipment in the desired direction until the puck 512 finds the next opening 520 . This first way of interaction between the actuator 506 and spring 508 , involving manipulation of the latch handle 522 , can thus be used to select an offset configuration. The latch handle 522 can also be used to overcome a safety stop described below, intended to prevent accidental sliding of the slider 504 completely off the rail 502 in a single action. That is, the handle 522 can be used when it is desired to remove the slider 504 and attached equipment from the rack.
[0062] The second way that the actuator 506 interacts with the spring 508 is to implement an automatic safety stop to prevent accidental sliding of the slider 504 and equipment fully off the rail 502 , which could be hazardous to personnel and equipment. As noted above, screw 514 extends through a slotted opening 516 in the actuator 506 . The slotted opening 516 allows the actuator 506 to move in relation to the spring 508 along an axis of the opening 516 , which is aligned with a longitudinal axis of the rail and slider assembly, which, in turn, extends along to a front-to-back axis of the rack. A middle section 530 of the spring 508 (bounded by bend lines 532 , 534 ) is angled in relation to the rail 502 and slider 504 so that bend line 532 is closer to the rail 502 than is 534 , and bend line 534 is closer to the slider 504 . When the screw 514 is at the end of the slotted opening 516 farthest from the handle 522 , the actuator 506 does not extend across the bend line 532 , and the puck 512 is biased against a slider 504 . However, when the screw 514 is at the end of the slotted opening 516 nearest the tab 522 , the end of the actuator 506 opposite the handle 522 extends beyond the bend line 532 causing the middle section 530 of the spring 508 and end section supporting the puck 512 to pivot about the bend line 532 so that the puck 512 is withdrawn from the opening 520 .
[0063] FIG. 6 shows a sequence of positions depicting the motion by which the safety lock deploys to prevent accidental sliding of the slider 504 and attached equipment fully off of the rail 502 . Specifically, the assemblies 540 - 543 show a series of positions corresponding to progressive movement of the slider 504 in the direction indicated by arrows 544 . As shown, the slider 502 includes slider tabs 526 extending inwardly from the flanged ends of the slider 502 . The actuator 506 may optionally include actuator tabs 524 extending outwardly therefrom. The actuator tabs 524 interact with the slider tabs 526 so that movement of the slider 502 to a defined position causes movement of the actuator, which, in turn, allows the puck 512 to fall into an opening 520 on the slider 502 to prevent further travel of the slider 502 .
[0064] In this regard, assembly 540 shows a position where the tabs 524 and 526 are separated and the screw 514 is disposed at the end of the slotted opening 516 closest to the latch handle 522 . In this position, the actuator 506 deflects the spring 508 so that the puck 512 is withdrawn from the openings 520 of the slider 504 and the slider 504 is free to slide on the rail 502 . Assembly 541 shows a position where the slider 504 has advanced to the point where the slider tabs 526 engage the actuator tabs 524 . Further movement of the slider 504 , as shown by assembly 542 , causes the actuator 506 to move in relation to the spring 508 such that the screw 514 has reached the end of the slotted opening 516 farthest away from the latch handle 522 —the limit of travel of the actuator 506 in relation to the spring 508 . In this position, the actuator 506 allows deflection of the spring 508 so that the puck 512 is biased against the slider 502 , and the puck 512 can then drop into the next opening 520 that comes into alignment with the puck 512 .
[0065] An operator can thus use the safety stop as follows. To install a piece of equipment on the rack or to slide the equipment to a desired offset or to access the equipment, the operator first pushes the latch handle 522 rearwardly until the screw 514 is at the end of the slotted opening closest to the latch handle 522 . As noted above, in this position, the slider is free to slide on the rail 502 . In the case of installing a piece of equipment, the slider tabs 526 can easily ride over the actuator tabs 524 as best shown in FIG. 7 where the arrow 550 shows the direction of travel of the slider 504 in relation to the actuator 506 as the equipment is installed in the rack. Specifically, the forward ends of the actuator tabs 524 are bent inwardly to define ramps 560 . As the equipment is installed, the rearward ends of the slider tabs 526 contact the surfaces of the ramps causing the actuator 506 to deflect inwardly so that the slider tabs 526 can ride over the actuator tabs. When the equipment is subsequently moved forwardly as shown in FIG. 6 and discussed above, the safety stop is engaged to prevent accidental travel of the slider fully off of the rail. In this regard, the position of the slider tabs 526 is selected to allow the desired access to the equipment without accidental falling from the rack. When it is desired to remove the equipment from the rack, the operator can press the latch handle inwardly and rearwardly so that the actuator tabs 524 pass under the slider tabs 526 . In this manner, the safety stop is overridden. It should be noted that an actuator/spring assembly of relatively simply construction allows for selection of an offset configuration, safety stop functionality, and simple installation and removal of equipment in relation to the rack. Further, the actuator/spring assembly is field serviceable in the event of damage.
[0066] FIG. 11 shows an alternative configuration of an actuator/slider assembly 1100 . The actuator 1102 is forced from a latch arm 1102 having a latch handle 1104 and a lock tine arm 1106 (side view shown at top of FIG. 11 ). The assembly 1100 further includes a spring 1108 that is generally of similar construction as the spring described in the embodiment above, but includes a cutout area 1110 that allows the spring 1108 to extend across the lock tine arm 1106 in the horizontal dimension. The operation of the assembly is the same as described above except that, when the puck 1112 drops into the opening 1114 in the slider 1116 , a tine 1118 at the end of the tine arm 1106 prevents the puck 1112 from being forced out of the opening 1114 .
[0067] FIGS. 8-10 show optional alignment bearings 800 used in a rack 802 . Specifically, FIG. 8 shows a perspective view of a section of the rack 802 , FIG. 9 shows a close-up of a portion of the rack section of FIG. 8 , and FIG. 10 is a front cross-sectional view of a portion of the rack section of FIG. 8 .
[0068] The rack 802 includes slider assemblies 804 and horizontal rails 806 mounted on vertical support posts 808 for varying offset configuration in relation to a front face 810 of the rack 802 , all as described above. The illustrated rack 802 further includes the noted alignment bearings 800 , also mounted on the vertical posts 808 and interposed between adjacent slider assemblies 804 . More specifically, the bearings 800 may be dimensioned so that the slider assembly 804 immediately above the bearing 800 lightly contacts or is very closely spaced from the bearing surface 812 when the slider assembly 804 and attached equipment is fully inserted into the rack. Moreover, at least the surface 812 may be formed from a material having frictional characteristics that facilitate easy sliding of the slider assembly 804 on the surface 812 when they are in contact. In the illustrated embodiment, the bearings 800 are formed from injection molded or extruded plastic.
[0069] The bottom edges of the bearings 800 are sloped upwardly at the front and back sections of the slider 800 (thus providing a symmetrical geometry so that the same construction can be used for left side and right side bearings 800 ) to facilitate alignment of the slider assemblies 804 on the rails 806 during insertion as will be described below. Also, the sliders 800 may include recesses 814 , as shown in FIGS. 9 and 10 , which may optionally house stiffening bars 816 to provide greater bending stiffness in relation to the longitudinal (front-to-back) axis of the bearing 800 .
[0070] In operation, the bearings 800 serve at least two functions: 1) facilitating alignment of the slider assemblies 804 to the rails 806 for equipment installation, and 2) enhancing the load rating of the rack 802 . In the former regard, the bearings 800 extend beyond the front ends 818 of the rails 806 as best seen in FIG. 9 . An operator can thus rest the slider assemblies 804 on the bearing surfaces 812 of bearings 800 forward of the rail ends 818 to initiate installation. This is accommodated by the upward slope of the front section of the bearing 800 immediately above the bearing at issue, which provides clearance and guidance of the slider assembly 804 . The slider assembly 804 can then be pushed rearwardly until the slider assembly 804 engages the rail 806 . The slope of the bearing 800 above the bearing at issue progressively forces the slider assembly 804 with attached equipment into a desired horizontal orientation as the slider assembly 804 is pushed towards the rail ends 818 , thus further promoting capture of the rails 806 by the slider assembly 804 .
[0071] The bearings 800 also enhance the load rating of the rack. For certain environments, e.g., racks deployed on aircraft or launch vehicles and racks supporting heavy equipment, the load bearing capacity of the rack may be critical. In this regard, load peaks may be experienced when the rack is accelerated and when the equipment is slid forwardly from the rack for access to the equipment, thereby increasing the moment on the slider 800 . As shown in FIG. 10 , the slider assemblies 804 , rails 806 and bearings 800 define a substantially continuous (though segmented) vertical column of material substantially at the side-to-side location of the load-bearing interface between the slider assemblies 804 and the rails 806 . In this manner, any slight deflection of the slider assembly 804 , e.g., due to elastic bending between the slider assembly 804 and rail 806 , causes loading to be transferred from the rail 806 to the bearing 800 . The bearings 800 thus function as braces to enhance the load bearing capacity of the rails 806 and rack 802 .
[0072] The bearings 800 increase the load rating of each slider assembly 804 . The bearings 800 may be designed to have zero tolerance between them and the slider assemblies 804 (slight interference fit), such that the bearings 800 not only support the slider above them, but also the slider below them. Then, if a slider assembly 804 is inserted at every position (e.g., every 1 U position), regardless if anything is mounted to it or not, the strength of each slider assembly 804 is greatly increased, in both the up and down axis. This is because all slider assemblies 804 are engaged in supporting each other on each side of the assembly and function as one structural unit. This facilitates the design of a rack that is able to withstand much higher loads, which may be desired for some applications (e.g., in mobile applications, where G-shock ratings may be important).
[0073] It can be appreciated that the slider can be pre-mounted onto equipment so that assembly of the equipment-mounting adapter is not required at the typically crowded rack location. Accordingly, installation at the rack is very simple, and there is no need to disturb adjacent equipment in neighboring racks of a data center. However, it is desirable in this regard to accurately mount the equipment so that the side-to-side spacing of the sliders matches the said spacing and the vertical position of the equipment does not result in interference of the equipment or mounting flanges with adjacent equipment or mounting flanges.
[0074] If an operator was only concerned about mounting the equipment, the mounting process could be addressed by simply providing a set of rails mounted on a table top. The rails could be mounted on the table top so that the horizontal spacing between the rails matched that in the racks (if different rack widths were used in the data center, multiple rail sets could be provided on the table top), and the vertical height of the rails above the table top was a fraction of 1 u (e.g., 0.5 u). The piece of equipment to be mounted could then be placed between the rails on the table top. Sliders could then be slid onto the rails. Finally, the mounting flanges on the sliders could be bolted to the front face of the equipment and/or the mounting adapters could be assembled between the equipment sides and the sliders. The equipment and sliders, as a unit, could then be removed from the table-mounted rails and inserted into the desired rack location as described above.
[0075] However, certain equipment has a height that is a multiple of 1 u. For such equipment, it will be appreciated that the same process as described above could be utilized but with multiple rail sets mounted on the table top, with the vertical spacing between rail sets selected to match that of the rack (e.g., 1 u spacing between vertically adjacent rail sets). The multiple u equipment would then be placed on the table between the stack of rails and mounted to the appropriate number of rail sets as described above. However, though this is easier than mounting the multiple u equipment to the sliders at the crowded rack (working at whatever height required), it is still somewhat difficult to assemble the side mounting adapters to each set of rails in the table-mounted stack.
[0076] FIGS. 12A-12B show an assembly fixture 1200 that can be used for mounting 1 u height or multi u height equipment to sliders. The fixture 1200 includes a deck 1202 for supporting a piece of equipment to be mounted and rail mounts 1204 for receiving slider assemblies 1206 to be mounted. The deck 1202 is supported by an elevator that can be operated by controls 1208 to move the deck up or down (in relation to the rail mounts 1204 ) in 1 u increments, or to move the deck to its top position. FIG. 12B shows the deck 1202 in its top position, and FIG. 12A shows the deck in a lowered position. The illustrated assembly 1200 also includes catering pins 1210 that can be moved in slots 1212 by operation of handle 1214 . Moving handle 1214 moves the left and right side pins 1210 symmetrically so that the pins are equidistant from the rail mounts 1204 .
[0077] To mount a piece of equipment, the equipment is placed on the deck 1202 between the pins 1210 and the deck 1202 is moved to its top position. The lever 1214 is then operated so that the pins 1210 engage the opposite sides of the equipment and center the equipment. Slider assemblies 1206 are then inserted on the rail mounts 1204 and attached to the equipment front face. Appropriate brackets or standoffs are then used to mount the slider assemblies 1206 to the equipment sides. If the equipment is a 1 u piece of equipment, the slider assemblies 1206 with attached equipment can then be removed from the fixture 1200 and inserted with the rack. It will be appreciated that the spacing of the rail mounts 1204 matches that of the rack rails. If different rack widths are employed in a data center, multiple fixtures 1200 may be utilized or the assembly 1200 can be constructed to allow repositioning of the rail mounts 1204 .
[0078] In the case of a multiple u piece of equipment, the controls 1208 can be used to lower the deck 1202 by an amount equal to the vertical spacing of rack rails. In this regard, the top position of the deck 1202 is selected to match the desired vertical spacing of the rail center to the equipment bottom, e.g., 0.5 u. Each time the “down button is pressed, the deck may be lowered in one increment of the rail spacing, e.g., 1.0 u. This process can be repeated until the desired number of slider assembly pairs are mounted on the equipment. The equipment can then be removed from the fixture 1200 and inserted at the desired rack location.
[0079] FIGS. 13A and 13B show perspective and side views of a set of rail assemblies 1310 a - c that include rail portions 1312 a - c and vertically segmented mounting flanges 1316 a - c , respectively. As shown, the rail portions 1312 a - c are shaped such that the vertically segmented mounting flanges 1316 a - c do not contact each other when the rail portions 1312 a - c are under a loaded condition (e.g., when the rail assemblies 1310 a - c are coupled to equipment). The rail portions 1312 a - c include mechanical interference ramps 1318 that are bidirectionally slanted. When slider assemblies pass adjacent vertically segmented mounting flanges 1316 a - c from either direction, the dimensions of the ramps 1318 are formed so that the ramped section of the rail portions 1312 a - c will control the separation of the flanges 1316 a - c as they pass each other and prevent them from contacting each other. If the rail portions 1312 a - c are set at or near the same horizontal offset and the mechanical load upon an upper slider begins to deform the upper slider, the ramps 1318 may contact each other and the upper slider will be supported, thereby limiting the amount of deflection it will experience, thereby preventing possible damage to that assembly. It should be appreciated that this feature may also work in other orientations where the load or acceleration direction is not vertical.
[0080] FIGS. 14A and 14B show side and perspective views of a removable insertion guide 1410 that may be operative to assist a user to insert equipment into a rack 1400 . Similar to racks described above, the rack 1400 may include a vertical side support post 1402 and a front surface 1404 . Further, the rack may include one or more rails 1406 . The insertion guide 1410 may include two arms 1414 and 1416 that include pins 1426 which may be inserted into openings (e.g., holes) in the vertical side support post 1402 . Further, the insertion guide 1410 may include a “funnel” portion 1412 that is shaped to receive and guide a slider that may be attached to a piece of equipment. To further secure the insertion guide 1410 to the rack 1400 , the insertion guide 1410 may include a plurality of fingers 1418 , 1420 , 1422 , and 1424 that are shaped and sized to secure the insertion guide 1410 to the front surface 1404 of the rack 1400 . The funnel portion 1412 of the insertion guide 1410 may be designed to support and guide a slider assembly during installation of equipment into the rack 1400 . The removable insertion guide 1410 may be symmetrical and may function on either side of the rack, front or back. The insertion guide 1410 may therefore be used individually or in one or more pairs (for multi U equipment with multiple sliders attached) to guide the insertion of equipment (or accessories, trays, or the like) into the rack. The guide 1410 may also be attached and removed or moved to a different location on the same or a different rack.
[0081] The foregoing description of the present invention has been presented for purposes of illustration and description. Furthermore, the description is not intended to limit the invention to the form disclosed herein. Consequently, variations, various combinations, and modifications commensurate with the above teachings, and skill and knowledge of the relevant art, are within the scope of the present invention. The embodiments described hereinabove are further intended to explain best modes known of practicing the invention and to enable others skilled in the art to utilize the invention in such, or other embodiments and with various modifications required by the particular application(s) or use(s) of the present invention. It is intended that the appended claims be construed to include alternative embodiments to the extent permitted by the prior art. | A universal mounting system is provided for use in connection with substantially any type of electronic equipment so was to reduce or substantially avoid the need for rail kids or other mounting assemblies that are its equipment specific for mounting equipment to racks. In one implementation, a uniform mounting system ( 101 ) includes a number of rail and slider assemblies ( 112 ). Each of the rail and slider assemblies includes a slider that is slightly mounted on a support rail. Each of the slider is includes mounting flange is and brackets for mounting the slider to a piece of equipment. The mounting flanges 116 that's collectively define a segmented vertical rail. A safety stop mechanism can be used to define very a offset figurations of the equipment with respect to a front end of the rack. | 0 |
BACKGROUND OF THE INVENTION
The present invention relates to bicycle racks and pertains more particularly to a combined bicycle rack and locking means.
Bicycles and motorcycles have become quite popular as a mode of transportation and a means of recreation. Because of this popularity and the ease of transportability of these vehicles, they have become a common target for thieves.
Many proposals have been made for locking these vehicles to prevent theft. These proposals, however, are generally ineffective. For example, if the wheels are locked to prevent riding the vehicle, the thief simply loads it in a truck and hauls it away. If the frame of the cycle is locked by means of a chain to a stationary object, the thief simply removes the wheels and leaves the frame if he cannot cut the chain. If he should find that a cycle is locked by a wheel to a stationary object, he simply takes the frame and remaining wheel. Thus, he simply takes individual wheels and frames, where available, and assembles them into complete units later.
Examples of the prior art approach to this problem are illustrated in the following patents:
U.s. pat. No. 557,900 issued Apr. 7, 1896 to Shannon
U.s. pat. No. 590,425 issued Sept. 21, 1897 to Smart
U.s. pat. No. 597,507 issued Jan. 18, 1898 to McIntosh
U.s. pat. No. 605,628 issued June 14, 1898 to Bradley
U.s. pat. No. 636,629 issued Nov. 7, 1899 to Butcher
U.s. pat. No. 698,277 issued Apr. 22, 1902 to Hammond
SUMMARY OF THE INVENTION
It is the primary object of the present invention to provide a bicycle support rack that includes means to effectively lock the major components of the bicycle to the rack.
Another object of the present invention is to provide a simple and inexpensive bicycle support rack that overcomes the above problems of the prior art.
In accordance with a primary aspect of the present invention there is provided a bicycle rack that includes channel means to receive the wheels of a bicycle with means to support the bicycle in a vertical position and lock it to the channel means.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other objects and advantages of the present invention will become apparent from the following description when read in conjunction with the accompanying drawings wherein:
FIG. 1 is an elevational view of a bicycle rack in accordance with the present invention;
FIG. 2 is a perspective view of the rack of FIG. 1;
FIG. 3 is an end view of the rack of FIG. 2; and,
FIG. 4 is a partial section taken generally along lines IV--IV of FIG. 3.
DESCRIPTION OF THE PREFERRED EMBODIMENT
With reference now to the drawings there is illustrated in FIG. 1 an elevational view of a rack in accordance with the present invention generally designated by the numeral 10 and shown supporting a bicycle of generally conventional design designated by the numeral 12. Although the present invention is to be described with respect to a bicycle it is to be understood that the present rack may be adapted to use for motorcycles and the like. The bicycle 12 has the usual chassis defined by a tubular frame having a lower frame portion 14 wherein is journaled the main drive sprocket and pedals. Rotatably secured to the ends of the frame are the usual front wheel 16 and rear wheel 18.
The rack itself comprises a base member defined by a generally U-shaped channel member having a bottom 20, and sidewalls 22 and 24 respectively. The channel member opens upwardly and receives the wheels 16 and 18 of the bicycle as illustrated in FIG. 1.
The base or channel member may be secured directly to a concrete slab or the like for stationary mounting or may be secured to a vehicle for transporting bicycles and the like. Bolts 26 and 28 for securing the channel are disposed directly beneath the wheels 16 and 18 so that they may not be removed. when the bicycle is locked into position therein.
A support arm 30 is secured in a suitable manner but preferably by pinning as by means of a rivet or the like 32 near the center of the base member and extends upward therefrom to engage and support the bicycle in the upright position as shown in FIG. 1. The support arm 30 is preferably pivoted to accommodate differences in position of the lower frame portion of different bicycles and also so that it may be folded down alongside the sidewall 22 to make it more compact for packaging or shipping. The support arm 30 also includes locking means in form of a slot 34 for receiving a lock portion to be described. A shield member 36 is formed as shown in FIGS. 2 and 3 to shield a padlock as shown best in FIG. 3. This lock shield is for the purpose of preventing the lock from being cut such as by means of bolt cutters or the like.
Suitable latching means for the bicycle comprises a pair of generally L-shaped arms 38 and 40 operatively interconnected by means of a shaft 42 rotatably mounted such as by means of a plurality of brackets 44 to the sidewall 24 of the channel member. A third L-shaped arm 46 is pivotally secured in a suitable manner such as by bracket and pin 48 to the rotatable shaft 42 near the center thereof. This pivotal connection permits the arm 46 to fold down along the channel as with arm 30 for ease in storing or packaging. The arm 46 includes a loop 50 formed on the outer end thereof and cooperatively with the slot 34 and support arm 30 to define locking means as shown in FIG. 3 for receiving a conventional padlock 52. The loop 50 extends through slot 34 as shown. Other suitable lock means may be provided.
Suitable spring means such as a tension spring 52 is operatively connected between sidewall 24 and arm 46 to pivot the latching means into the upright or latched position as best seen in FIGS. 1 and 3.
The rack and lock assembly is prepared to receive a bicycle by folding the latching means comprising the arms 38, 40 and 46 in a downward position as shown in FIG. 2. The bicycle is then placed with the wheels 16 and 18 within the channel between sidewalls 22 and 24 and leaned against the upright arm 30 to support it in the upright position. The latching means is then permitted to pivot upward so that the arms 38 and 40 extend across the open channel as shown in FIG. 3 and over the lower portion of the wheels 15 and 18 as seen in FIG. 1. At the same time, or simultaneously therewith, arm 46 extends through the frame over the lower portion 14 thereof and extends into slot 34 to a position as shown in FIG. 3 to receive a padlock 52. The bicycle is then supported and locked into a position in the rack as shown in FIG. 1. By this arrangement it is seen that the three major components of the bicycle are simultaneously locked into position by means of the respective locking means. Thus, the wheels 16 and 17 are locked by the arms 38 and 40 respectively and the frame is locked into position by means of arms 46 and 30 cooperating.
Thus, from the above description it is seen that we have provided a simple inexpensive bike rack and locking assembly that is operative to simultaneously lock the two wheels of the bicycle and the frame assembly into position in the rack.
While the present invention has been described with respect to a specific embodiment, it is to be understood that changes and modifications may be made therein without departing from the spirit and scope of the present invention as defined in the appended claims. | There is disclosed a bicycle rack with channel means to receive the wheels, and latching means including a plurality of arms to simultaneously latch the wheels in the channel, and the frame to the channel. An upstanding support arm is operative to support the bicycle in the upright position and to cooperate with the latching means to provide locking means for the rack. | 8 |
BACKGROUND OF THE INVENTION
The invention relates to a folding machine for the shirts of regular notched collar or for leisure shirts, and more particularly a machine to fold the shirts of all neck openings into a fixed configuration.
Regularly, the shirts must be folded and packed in a fixed rectangular configuration prior to offering for sale, so as to provide a neat, outstanding and eminent appearance to attract consumers to buy.
Currently, there are some shirt folding machines available on the market. However, the conventional shirt folding machines that are commonly used are of fixed type applicable for single size. While folding the shirts of different sizes in neck opening, it requires to change the neck opening fixation part. Therefore, the conventional shirt folding machine is not convenient to use and requires longer processing time and several sets of different sizes of neck opening fixation parts, and further, the processing cost is high.
In view of said disadvantages existed in conventional shirt folding machines, there is a strong demand for a folding machine applicable for use to fold the shirts of all neck openings.
SUMMARY OF THE INVENTION
The invention relates to a shirt folding machine to fold the shirts of regular notched collar or leisure shirts into a fixed configuration, which comprises stroke adjustable neck opening fixation plates, revolvable shirt folding mold board, and ironing board. The shirt to be folded is mounted on the neck opening fixation plates by slip joint, while the neck opening fixation plates are arranged to relatively close to each other, by means of the separation of said neck opening fixation plates the neck opening of the shirt to be folded is fully stretched; by means of the clamping effect of the shirt folding board and the ironing board the shirt to be folded is firmly clamped therebetween for ironing process; by means of the support of the shirt folding mold board, the protruding portion of the shirt is well folded, in accordance with the configuration of the shirt folding mold board, into preferred rectangular arrangement for distribution on the market.
Said shirt folding machine further comprises two cylindrical driving mechanisms and respective pedal switches. The operator controls said two pedal switches by foot to respectively drive neck opening fixation plates, shirt folding mold board and ironing board to proceed with the folding process.
The stroke adjusting device for adjusting the stoke of the neck opening fixation plates comprises a screw and one set of symmetrical check blocks that are mounted on the screw by means of screw joint. Said check blocks are arranged to respectively stop the far apart neck opening fixation plates at proper locations. Therefore, the relative stroke of the neck opening fixation plates can be adjusted by means of turning the screw to change the distance between said two check blocks, i.e. the neck opening fixation plates can be adjusted to stretch the neck openings of all sizes.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention as well as its many advantages may be further understood by reference to the following detailed description and drawings in which:
FIG. 1 is a perspective view of a folding machine embodying the invention, wherein the central portion is illustrated in a sectional view;
FIG. 2 is another perspective view of the embodiment according to FIG. 1;
FIG. 3 is a top view of the embodiment taken in FIG. 2, wherein the folding plate and the driving cylinder are not shown;
FIG. 4 is a bottom view of the embodiment taken in FIG. 3, wherein the housing is illustrated in a sectional view; and
FIG. 5 is a longitudinal sectional view of the embodiment above described, wherein the embodiment is arranged on a table.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Please refer to the drawings above described. The folding machine 10 according to the invention, is to help the operator to fold the clothes into a fixed shape, which is applicable for folding the clothes of all sizes in neck opening.
The folding machine 10 comprises a housing 12, two neck opening fixation plates 20 22 arranged bilaterally to make relative movement, two check blocks 30 32 and the related screw 34 for adjusting the stroke of said neck opening fixation plates 20 22, a pivotally movable shirt folding mold board 40 mounted on the housing 12, an elevating ironing board 50 arranged below said folding plate 40, a power cylinder and its pedal switch to respectively drive all moving members.
Referring to FIG. 5, the housing 12 is set in the upper surface 70 of a table and firmly fixed therein such that the operator can conveniently use the folding machine 10 above the face 70 of the table, to fold the shirts into a fixed shape; said housing 12 is to contain and support all the component parts of the folding machine 10.
Said neck opening fixation plates 20 22 are respectively arranged at two symmetric positions bilaterally in the housing 12 to relatively slide along the mandrel 24 and the guide way 23 in transverse direction; two symmetric and single acting cylinders, first cylinder and second cylinder 25 26 are arranged to act simultaneously to drive said neck opening fixation plates 20 22 to respectively make reciprocal movement in transverse direction; two symmetric check blocks 30 32 are arranged to respectively confine the stroke of the neck opening fixation plates 20 22. Regularly, when compressed air is not available in the first and the second cylinders 25 26, the neck opening fixation plates 20 22 are pushed outward by respective springs (not shown in the drawing) arranged in the cylinders 25, 26, to contact and be stopped by the respective check blocks 30 32 at pre-fixed positions. Before setting the shirt to be folded over the neck opening fixation plates, the operator must step on the first pedal switch 60 to let the compressed air run through air hose 64 into first and second cylinders 25 26, because the pressure of the compressed air overpasses the spring force of the springs of respective cylinders, therefore, the neck opening fixation plates 20 22 are driven inward to return to the central position; at this moment, the distance between said two neck opening fixation plates 20 22 is minimized to allow the operator to conveniently arrange the shirt to be folded letting the neck opening slip over the neck opening fixation plates 20 22; then, the first pedal switch 60 is released and the compressed air is stopped from entering the first and the second cylinders 25 26, the neck opening fixation plates 20 22 are thus pushed outward by means of spring force and stopped by respective check blocks, to stretch the neck opening of the shirt.
The front end of each said neck opening fixation plate 20 22 is arranged in a curved shape to match with the neck opening, and the rear end of each said neck opening fixation plate is arranged to provide a curved slot 27 28; by means of a bolt 29 through the curved slot 27 28, each neck opening fixation plate 20 22 is tightly screwed up with respective matching plate 14 16, such that the contained angle between the matching plate and the neck opening fixation plate is adjustable to fit all styles of neck openings.
The check blocks 30 32 which are arranged to confine the stroke of the neck opening fixation plates 20 22 are threaded by a screw 34 and arranged at both ends of the screw 34, the central part of the screw 34 is a smooth portion 36, and the bilateral threads have a same pitch and are arranged in reverse direction, therefore, when the operator turns the revolving button 38 which is tightly mounted on the screw 34, the check blocks 30 32 will be driven to move relatively, and the distance between the check blocks 30 32 will be adjusted accordingly; When the distance between said two check blocks 30 32 is adjusted, the stroke of the two neck opening fixation plates will be changed accordingly to fit the shirts of all styles of neck openings.
A braking device 80 is arranged to provide a braking force on the smooth portion 36 of the screw 34 by means of the push of the spring 82, to prevent the screw 34 from turning around to cause displacement of the check blocks 30 32 due to impact force from neck opening fixation plates. As afore described, before turning the revolving button 38, the operator must press down the crank 84 of the braking device 80 to let the braking device 80 break away from the screw 34, so as to let the screw 34 be freely turned round.
For easy operation in folding process, in addition to the stroke adjustable neck opening fixation plates 20 22 to stretch the neck opening of the shirt to be folded, the folding machine 10 is arranged to provide a pivotally movable shirt folding mold board 40 to let the operator fold the shirt by means of the configuration of the plate 40. In order not to interfere with the procedure to slip the neck opening of the shirt over the neck opening fixation plates, the shirt folding mold board 40 is designed to be liftable, which is closed up during folding process. The shirt folding mold board 40 which is replaceable is fixedly attached to a triangular plate 42 by means of screws 41; said triangular plate 42 is connected with a transverse mandrel 44 by means of slip joint; a third single action cylinder 46 is arranged to control the lifting or closing of the shirt folding mold board 40; said third single action cylinder 46 is movably connected with the housing 12 and the triangular plate 42 respectively at both ends for pivotal movement. When compressed air is introduced into the third cylinder 46, the shirt folding mold board 40 is forced to close up at the top of the housing 12; when there is no compressed air available in the third cylinder 46, the shirt folding mold board 40 can either be lifted or be easily and simply closed up at the operator's own will, by applying little force.
Said shirt folding mold board 40 is designed according to the style of the shirt to be folded, or the folded style and size preferred; more particularly, the shirt folding mold board 40 is replaceable when necessary.
Said elevating ironing board 50 which is arranged below the shirt folding mold board 40 is controlled by the fourth cylinder 52 to make longitudinal movement; at regular time, the compressed air does not enter the fourth cylinder 52, and the ironing board drops to a lower position due to gravity; when compressed air enters the fourth cylinder 52, the piston rod of the fourth cylinder 52 will immediately lift the ironing board 50 to a higher position adjacent to the closed up shirt folding mold board 40.
When to start folding process by using the present folding machine, the operator should button up the shirts to be folded in advance, and then, follow the following procedures to proceed with folding process: (a) open the shirt folding mold board 40, and step on the first pedal switch 60 to let the neck opening fixation plates 20 22 be pulled back inward, so as to let the neck opening of the shirt to be folded be arranged on the neck opening fixation plates by slip joint with the front of the shirt facing downward; (b) make sure that all the buttons of the shirt to be folded are arranged inside the button channel 18 at the central line of the housing 12; (c) close up the shirt folding mold board 40 by hands, and release the first pedal switch 60 to let the two neck opening fixation plates 20 22 move outward respectively to properly stretch the neck opening of the shirt to be folded; (d) step on the second pedal switch 62 to concomitantly introduce outside compressed air through the air hose 66 into the third and the fourth cylinders 46 52, so as to let the shirt be sandwiched by the folding mold board 40 and the ironing board 50 for ironing treatment on the front of the shirt; (e) continuously step on the second pedal switch 62, use the hands to stretch the protruding portion of the shirt beyond the shirt folding mold board 40, and start to fold the protruding portion of the shirt according to the configuration of the mold board 40, to let the shirt be folded into preferred arrangement, the well folded shirt may be fixed by pin and be supported by paper board to let the folded style be well maintained; and (f) release the second pedal switch 62 and step on the first pedal switch 60 again, so as to lift the shirt folding mold board 40 and remove the well folded and ironed shirt.
While proceeding with above said procedure (a), the operator shall have to reach out the hands between the shirt folding mold board 40 and the lower ironing board 50 to lift the mold board 40, at this moment, if the operator or someone else steps on the second pedal switch 62 unintentionally, the hands of the operator may be clamped by the mold board 40 and the ironing board 50 to cause accident; therefore, a microswitch 58 is provided to prevent any accident, when the shirt folding mold board 40 is lifted, the microswitch is triggered simultaneously to cut off the power for the second pedal switch 62, such that the second pedal switch 62 is temporarily out of work, and accident can be prevented.
The movable neck opening fixation plates 20 22 and the related portion of the standing housing 12 are arranged to provide linear measure graduation and scale mark 91 92 for identification of the stroke of the neck opening fixation plates or the applicable size of neck opening.
Either a skilled operator or a beginner can easily learn to use the present folding machine to help shirt folding and to improve the productivity. When necessary, the stroke of the neck opening fixation plates can be adjusted in a simple and efficient way, to match with different size of neck openings of the shirts to be folded. While adjusting the stroke of the neck opening fixation plates, there is no need to remove any parts of the machine.
In addition to the above described advantages, the present folding machine 10 has a simple structure, of which the manufacturing cost is inexpensive.
As indicated, the structure herein may be variously embodied. Recognizing various modifications will be apparent, the scope hereof shall be deemed to be defined by the claims as se forth below. | A shirt folding machine, comprising stroke adjustable neck opening fixation plates, revolvable shirt folding mold board, and ironing board; the shirt to be folded being slipped on the neck opening fixation plates that are arranged to relatively close to each other, by means of the separation of said neck opening fixation plates the neck opening of the shirt to be folded being fully stretched; by means of the clamping effect of the shirt folding board and the ironing board the shirt to be folded being firmly clamped therebetween for ironing process; by means of the support of the shirt folding mold board, the protruding portion of the shirt clamp being well folded, in accordance with the configuration of the shirt folding mold board, into preferred rectangular arrangement for distribution on the market. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to flat bed knitting machines which can be programmed to produce prescribed designs in a fabric and has particular application to home knitting machines.
2. Description of the Prior Art
Programmable home knitting machines which pick up patterning instructions photoelectrically one row at a time from a program card on each knitting stroke of a carriage and utilize such instructions during the following knitting stroke are known and are exemplified by the machines of U.S. Pat. No. 3,885,405 and Japanese laid-open Pat. 85853/73. It is a disadvantage of such machines that they must pick up patterning instructions while the carriage moves at knitting speed, since this complicates the design problem and increases cost. In such machines a movable photoelectric reading head scans data on a program card which is stationary on the bed, and because of the speed at which the carriage may be moved high quality and therefore costly light emitting diodes (LED's) and phototransistors must be used in the reading head if the card is to be read accurately. It is also difficult to obtain accurate readings in such machines because there is no convenient way of shielding the programmed card from ambient light. Accuracy in the reading of a card on the bed by a reading head on the carriage is also difficult to obtain because of the liberal tolerances which must be provided between the carriage and the bed, the liberal tolerances being required to assure that any carriage or bed of any machine can be substituted for any other in the production line such that they may be produced at a reasonable cost.
SUMMARY OF THE INVENTION
In the home knitting machine for the invention, an enclosed card reader is provided on the carriage of the machine. A program card bearing patterning instructions is moved through the reader by an operator and all of the data on the card is read prior to knitting during one pass of the card through the reader. The operation of the reader does not depend upon movement of the carriage and the card may be read as slowly as the operator pleases. A memory capable of storing all of the data read from the card is provided on the carriage and the memory is loaded as the card is read. When the carriage of the machine is operated to knit fabric, signals representing the data stored in the memory are recalled from the memory by sequencing control means including a pulse generator on the carriage which produces control pulses in synchronization with the carriage movement and causes needle selectors also on the carriage to be operated in accordance with the data signals and so provide for the reproduction in a fabric of the design on the card.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a home knitting machine according to the invention;
FIG. 2 is a plan view of a program card for use with the knitting machine;
FIG. 3 is a block diagram showing components of the control system of the knitting machine of the invention and their interrelation;
FIG. 4 is a schematic view in perspective of the pulse generator of said control system;
FIG. 5 (a and b) are diagrams showing the signal outputs of components of the pulse generator;
FIG. 6 is a somewhat schematic fragmentary botton plan view of the carriage illustrating the operation of one of the needle selectors of the machine of the invention and;
FIG. 7 is a view taken on the plane of the line 7--7 of FIG. 6.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1 of the drawings, reference characters 10 and 12 designate the bed and carriage respectively of the home knitting machine of the invention. The carriage is slidably mounted on guide rails 14 and 16 affixed to the bed, and includes handles 18 and 20 which an operator may grasp and utilize to move the carriage back and forth on the bed. Knitting needles 22 are supported in side by side relation in the bed 10 and are caused to follow a selected path through conventional camming in the carriage as determined by the operation of electromagnetic needle selectors 24 and 26. Such needle selectors are operated according to a prescribed design and the needles 22 being thereby caused to move along one path or another through the carriage camming select either a base or a secondary yarn.
The needle selectors 24 and 26 are responsive to the operation of a control system which is wholly carried by the carriage 12 and includes a control switch 27 (OPK switch); a photoelectric reader 28 capable of detecting an entire design indicated on a program card 30 during one pass of the card through it; a silicon memory 32 capable of storing all of the patterning instructions read by the card; and sequencing control means including an up-down column counter 34 which regulates the admission and recall of signals to and from the memory, a row counter 36 and multiplexer 38 which regulate the recall of signals from the memory, and a pulse generator 39. The memory associated control components 34, 36 and 38 may be on separate silicon chips as shown or incorporated into a single chip with the memory. Batteries 40 and 42 may be utilized as the power supply for the control system and mounted on the carriage as shown to eliminate the necessity of providing power lines between a remote stationary power source and the movable carriage. The OPK switch 27 is a three position switch which an operator may move from a first position O in which the control system is turned off, to a second position P in which the system is conditioned for reading the program card 30 into the memory 32, from the second to a third position K in which the system is conditioned for knitting a programmed design, and from a third position back to the off position.
The card which may be best seen in FIG. 2 is used to instruct the needle selector control system concerning a design which is to be produced on the knitting machine. As shown the card includes mutually perpendicular lines which define rectangles 44 that extend in numbered columns 1 through 32 and numbered rows 1 through 16. The card also includes a row of strobe markings 46 which are provided for a purpose hereinafter explained. An operator indicates the design he wishes produced, such as that shown in FIG. 2, by darkening selected ones of the rectangles 44 on the card with a pencil or other marker (preferably one leaving an erasable mark), and then feeds the card (left end first) through the reader.
The reader includes a paired light emitting diode (LED) and phototransistor for each of the numbered rows on the card and for the row of strobe markings 46. In FIG. 3 which shown the control system for the needle selectors 24 and 26, the LED - phototransistor pairs 48R 1 - 50R 1 , 52R 16 - 54R 16 , and 56R s - 58R s have been illustrated for row 1, row 16 and the strobe markings respectively, and it is to be understood that like LED -- phototransistor pairs are included in the reader for each of rows 2 through 15. The LED -- phototransistor pairs for the rows each connect with the memory 32 through amplifying means, as shown for the LED -- phototransistors pairs 48R 1 - 50R 1 and 52R 16 - 54R 16 at 58 and 60 respectively. The LED -- phototransistor pair 56R s - 58R s connects through amplifying means 64 with the memory 32 and up-down counter 34 when the OPK switch 27, which controls the opening and closing of contacts 68 and 70 and of contacts 72 and 74 is in the program position. In any other position of the OPK switch, the LED -- phototransistor pair 56R s - 58R s is disconnected from the memory 32 and from the up-down counter 34. Contacts 73 and 75 are closed by the OPK switch when the OPK switch is in the program position and contacts 76 and 78, the opening and closing of which is also controlled by OPK switch 27 are closed when the OPK switch is in either the program or knit position. Each of the LED - phototransistor pairs in the reader is therefore enabled when the OPK switch is in the program position, but not otherwise, by the output voltage V 1 of a voltage converter 80 which has as its potential source, the power supply of the control system, shown as the batteries 40 and 42. The memory 32 is also enabled by the voltage V 1 whenever contacts 76 and 78 are closed by reason of the OPK switch being in either the program or knit positions, but is not otherwise operable. The voltage converter in addition to providing the voltage V 1 also provides a voltage V 2 at a higher potential for operating the needle selectors 24 and 26. The OPK switch, when moved from the off to the program position closes contacts 86 and 88 to condition the memory for writing and when moved from the program to knit position closes contacts 86 and 90 to condition the the memory for reading. Contacts 92 and 94 are also closed by the OPK switch when it is moved from the off to program position and as a consequence mono-stable multivibrator 95 (one shot) is caused to produce a voltage pulse which is then applied to up-down counter 34 and row counter 36 presetting them to column address O and row address O respectively. The OPK switch also closes contacts 96 and 98 when it is moved from the off to program position causing a directional signal to be applied to the counter, the signal being such as to cause the counter to count up.
With the OPK switch in the program position, the machine may be programmed to knit the particular design on the program card by feeding the card through the reader. The LED-phototransistor pairs in the reader are all arranged in a line and as a card moves through the reader the columns in the design area of the card, and the strobe markings, each of which is in alignment with the trailing half of a column, appear successively under the LED-phototransistor pairs. Phototransistor 58R 2 detects the strobe marks and the other phototransistors detect the presence or absence of markings within the design area of the card. As previously noted the up-down counter 34 was set to address O when the OPK switch was moved from the off to the program position and readings from the first numbered column on the card are therefore recorded in the memory at this address when phototransistor 58R s detects the first strobe mark, a write pulse being then applied to the memory over contacts 68 and 70. As the card moves through the reader, the counter is incremented by one each time the phototransistor moves beyond the trailing edge of a dark strobe mark to a light area and signals from the various columns are successively recorded as the dark strobe markings are detected causing a write pulse to be applied to the memory. The memory 32 is in the form of a semiconductor chip and is of a well known type of which Intel's P/N 2101, Signetics 2606 and the industry wide P/N 1103 are examples. The up-down counter 34 is also a semiconductor chip of a known type of which Texas Instruments Counter P/N 74191 is an example.
After the program card has been read, the OPK switch may be moved from the program to knit position to ready the machine for knitting. When the OPK switch is so moved it opens contacts 68 and 70 to disconnect the phototransistor 58R s from the memory and opens contacts 72 and 74 disconnecting phototransistor 58R s from the column counter 34. Contacts 100 and 102 which are open in the off and program positions of the OPK switch are closed thereby causing voltage V 1 to be applied as an enabling voltage to the row counter 36. Contacts 104 and 106 which are closed in the program position of the OPK switch and then cause a disabling voltage signal (ground potential) to be applied to AND gates 108 and 110 are opened when the OPK switch is moved to the knit position whereupon the disabling voltage signal is removed from the gates rendering the needle selectors operable. Contacts 72 and 112 are closed to connect the up-down counter to AND gate 114 which responds to signals from a photo-interrupter module 116 of the pulse generator 39 and a flip-flop 118, and contacts 120 and 122 are closed to connect the up-down counter and row counter to a flip-flop 124 which responds to signals from the aforesaid photo-interrupter module 116 and to a second photo-interrupter module 126 of the pulse generator.
The photo-interrupter modules of the pulse generator (See FIG. 4 ) each include a light emitting diode (LED) and phototransistor as shown for module 116 at 128 and 130 respectively and for module 126 at 132 and 134 respectively, such LED's and phototransistors as shown being located on opposite sides of a toothed wheel 136 in the pulse generator. The toothed wheel 136 is affixed to a shaft 138 which is mechanically linked through a toothed pulley 140, also affixed to the shaft, and a timing belt 142 to gearing (not shown) as, for example, a pinion on the carriage and rack on the bed of the machine for driving the wheel as the carriage is moved across the bed. The wheel 136 moves in synchronism with the carriage and equally spaced teeth 144 on the wheel intermittently interrupt light between the LED and phototransistor in each of the photo-interrupter modules causing the modules to produce output pulses. Modules 116 and 126 are so located and the number of teeth 144 on wheel 136 is such as to cause module 116 to produce a counting pulse (FIG. 5a) each time the carriage passes from one needle area of the bed to the next, and module 126 to produce pulses (FIG. 5b) which lead the pulses from module 116 by 90° when the carriage is moved in one direction (to the right) and which lag the pulses from module 126 by 90° when the carriage is moved in the other direction (to the left). The output signal from module 116 controls the up-down counter 34 of FIG. 3, and the output signals from module 116 and 126 jointly control the operation of flip-flop 124 and so cause the flip-flop to provide an output signal indicative of the direction of movement of the carriage.
With the machine readied for knitting an operator choses one of the needles in the bed to knit the design fragment indicated by the presence or absence of a mark in column one, row one, on the program card. This is accomplished by the operator positioning the carriage so that the right needle selector may act first upon the chosen needle during knitting (the appropriate position being defined by the alignment of a mark 148 on the carriage with the said needle), and by the operator then depressing button 150 on the carriage to momentarily close contacts 152 and 154 (See FIGS. 1 and 3). The closing of contacts 152 and 154 sets flip-flop 118 which then provides an input to gate 114 permitting the up-down counter to be incremented or decremented in response to the operation of a photo-interpreter module 116.
The machine is threaded with a secondary yarn as required for knitting the design pattern in a base yarn previously cast on the machine and the carriage is moved first to the right and then back and forth across the bed to knit the design on the card. Initially column 1 information is read out of the memory since the up-down counter is at address O when button 150 is depressed (the counter having been so set when the OPK switch was moved from the off to program position closing contacts 92 and 94), and row 1 is selected by the row counter 36 and multiplexer 38 since the row counter is then also at 0. As the carriage is moved to the right on the bed beyond the chosen needle, up-down counter 34 responding to the operation of module 116 is incremented once each time the carriage moves over a new needle location. The counter is thereby caused to sequentially address the 32 columns of information in the memory and after each 32 counts repeat the process. Such column information is read into the multiplexer and the multiplexer which is at address O selects from each column the information in row one. During the said first knitting stroke of the carriage to the right a directional signal from flip-flop 124 directly transmitted to the gate 108 and through an inverter 109 to gate 110 causes the right needle selector 24 to be operated in response to signals from the multiplexer to the gates but prevents the operation of the left needle selector.
After the carriage has been moved beyond the fabric being knitted the operator reverses its direction causing it to be moved to the left whereupon the row counter is incremented by one and the up-down counter is caused to count down rather than up, both changes being effected in response to a changed directional signal from flip-flop 124. The up-down counter is decremented by one count as each needle location is traversed by the carriage, the column information is extracted from the memory in reverse order sequentially and repetitively, and the multiplexer because of the changed row selects the information in row 2 of each of the columns. By reason of the changed directional signal at flip-flop 124 which is reflected at gates 108 and 110, the left needle selector is caused to operate in response to output signals of the multiplexer transmitted to the gates and the right needle selector is prevented from operating. As the carriage moves to the left such left needle selector is operated to cause that portion of the design appearing in the second row on the program card to be knitted repetitively across the fabric. Successive rows of the design are formed in successive courses of the fabric knitted on the machine as the carriage is moved back and forth across the machine bed. Sixteen rows of design are produced in as many courses of fabric and the entire design is reknitted each time sixteen courses have been completed, such repetition being controlled by the row counter which counts up to 16 and then repeats such counting process. The row counter 36 is a semiconductor chip and is similar to the column counter 34 but lacks the up-down feature. An example of a suitable row counter is Texas Instruments counter P/N 74161.
The needle selectors 24 and 26 are without moving parts and rely solely on magnetic force to influence the positions of needles. Other types of needle selectors having moving parts that actuate needles and so influence their position might be used instead. The needle selectors 24 and 26, both of which are alike, function during movement to the right and left, respectively, of the carriage in a manner made apparent in FIGS. 6 and 7. The selector 24 includes a permanent magnet 156 fastened against the upper limb 157 of a C-shaped channel 158 of magnetic material having a lower limb 159. The upper and lower limb 157 and 159 of the channel 158 define a gap 160 which diverges toward the left as shown in FIG. 7 and presents opposing north and south magnetic poles as indicated. Needle butts 162 move through the selector as the carriage is moved on the bed of the machine and are caused by guides 164 and 166 to pass into the narrowest portions of the gap 160. A hole 172 is formed in the limb 157 adjacent to the narrowest portion of the gap 160 which so reduces the strength of the upper or north pole of the opposed magnetic poles developed solely by the permanent magnet 156 that needle butts guided into the gap 160 will be attracted to the lower or South pole against limb 159 and thereafter continue along limb 159 (needles 22a) because of the separation caused by the divergence of the pole faces.
A magnetizable core 174 is attached to the upper limb 157 of the channel 158 adjacent to the hole 172 and a coil 176 is so arranged on the core 174 so that when the coil is energized a strong electro-magnetic pole is produced on the core 174 of the same polarity as that produced by the permanent magnet 156 in the gap 160. When a needle butt is in the gap while the coil 176 is energized, the upper or North magnetic pole of the opposed magnetic poles in the gap will be the strongest pole and will attract that needle butt against the upper limb 157 and it will continue along the upper limb (needles 22b) because of the separation caused by the divergence of the pole faces.
Numerous alterations of the structure herein disclosed will suggest themselves to those skilled in the art and it is to be understood that the present disclosure relates to an embodiment of the invention which is for purposes of illustration only. It is not to be construed as a limitation of the invention. All modifications which do not depart from the spirit of the invention are intended to be included within the scope of the appended claims. | The carriage of a home knitting machine is provided with a reader operable independently of any movement of the carriage of the machine for reading out patterning instructions on a programmed card prior to knitting, an electronic memory for storing the signals read from the card, and means for recalling the stored signals from the memory in synchronization with movement of the carriage during knitting and for causing the operation of needle selectors on the carriage in accordance with the recalled signals to provide for the formation in a fabric of a pattern defined on the card. | 3 |
BACKGROUND OF THE INVENTION
[0001] The present invention relates to groundwater sampling systems, and more particularly, to a vacuum driven ground water sampling system for collecting groundwater samples from shallow wells.
[0002] Submersible pumps have been used where the depth to the water is more than 25 feet below ground surface (ft bgs). Most environmental monitoring wells are completed in the uppermost water bearing formation. In most of the United States the depth to water is less than 25 ft bgs. There are several problems with using existing submersible pumps.
[0003] When using a submersible pump, the pump, electrical line, and tubing must be decontaminated prior to sampling each well. Decontamination prevents cross-contamination between wells, assuring quality control of the sampling activities. Proper decontamination is a time consuming process. In addition, in anomalous sample results are obtained, additional time and expense are required to address the anomalous results in a sampling report and the possible incurring of the expense of resampling.
[0004] When using a submersible pump, it is difficult for one person to handle the pump, electric line and tubing keeping all components off of the ground as required by standard sampling protocol to prevent possible cross-contamination. Sampling is much easier for two people, however, labor is a significant portion of the expense of groundwater sampling and while the second person makes sampling easier, they have little effect on sampling times.
[0005] In many cases, the groundwater removed from monitoring wells contains significant concentrations of compounds that are considered by the United States Environmental Protection Agency to be hazardous to human health. A health and safety plan is required to be prepared for all sites so that exposure of sampling personnel to these compounds is identified and minimized. When using submersible pumps, the water in the discharge lines should not be allowed to drain back into the well, to prevent cross-contamination and to minimize the effect the pumping has on water chemistry. Often, the water in the discharge lines ends up being drained on the ground and presents an exposure to sampling personnel.
[0006] Small submersible pumps designed to work in 2-inch diameter wells are sensitive to handling any abrasive material which is a frequent occurrence in groundwater sampling. In addition to damage to the impeller of any centrifugal type pump, the small submersibles have Teflon wear surfaces rather than bearings. These wear surfaces are very sensitive to abrasion and frequent maintenance is required.
SUMMARY OF THE INVENTION
[0007] The present invention provides a portable sampling system for collecting groundwater samples from shallow wells. The sampling system includes an air pump to apply a vacuum to a steel tank to draw water from a well, tubing, valves and a power supply such as a battery or a portable gasoline-power electric generator. The sampling system is mounted on a portable platform. When the tank is full of sampled water, the air flow from the air pump can be reversed to pressurize the tank and force the water from the tank through a discharge line. As many as three groundwater monitoring wells can be sampled before emptying the tank. In addition to serving as a pump, the system will also contain fluid produced while sampling, act as a sampling platform, and can be used for sample storage. Use of an air pump in combination with a tank eliminates the possibility of a change in the contaminated water chemistry due to pump interaction. Additionally, sediment and debris do not contact the air pump and thus does not affect maintenance and performance of the air pump. Furthermore, contaminated wafer from a well remaining in a sampling line may be allowed to drain back into the well without cross-contamination or changing the chemistry of the contaminated water. The vacuum may also pull all of the contaminated water into the tank thereby preventing the contaminated water from spilling on the ground and exposing personnel to hazardous materials. Disposable lines may be used to eliminate the need to decontaminate sampling lines.
[0008] Other advantages of this invention will become apparent from the following description taken in connection with the accompanying drawings, wherein is set forth by way of illustration and example, a preferred embodiment of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] [0009]FIG. 1 is an electrical/pneumatic/hydraulic schematic illustration of the sampling system of the present invention.
[0010] [0010]FIG. 2 is a side elevation view of the sampling system of the present invention.
[0011] [0011]FIG. 3 is a front elevation view of the sampling system of FIG. 2.
DETAILED DESCRIPTION
[0012] Referring to FIG. 1, the portable groundwater sampling system of the present invention is generally indicated by reference numeral 10 . The groundwater sampling system 10 includes a DC powered air pump 12 which supplies a vacuum to steel tank 14 to draw water through sample line 16 , ball valve 18 and check valve 20 into the tank 14 . When the tank 14 is full, the flow of air from air pump 12 may be reversed to pressurize tank 14 and force the water from the tank 14 through check valve 22 , ball valve 24 and out discharge line 26 or drain valve 27 .
[0013] The air pump 12 may be powered by a 12-volt DC battery 28 carried on the sampling system 10 or can be operated from a vehicle battery (not shown). Power to air pump 12 is controlled by an ON/OFF switch 30 . Although shown as one air pump in the figures, two or more smaller air pumps connected in parallel may be used. A normally-closed high-level float switch 32 in tank 14 powers an indicator light 34 to indicate when the tank 14 is full.
[0014] A 4-way valve 36 switches connection of the pump inlet line 38 or pump exhaust line 40 to tank vacuum/pressure line 42 . When inlet line 38 is switched to vacuum/pressure line 42 , air pump 12 evacuates tank 14 and pump exhaust line 40 is connected to exhaust/inlet line 44 . When exhaust line 40 is switched to vacuum/pressure line 42 , air pump 12 pressurizes tank 12 and pump inlet line 38 is connected to exhaust/inlet line 44 . A filter and moisture separator 46 filters the incoming to air pump 12 through inlet line 38 . A pressure gauge 48 is provided to monitor the pressure or vacuum in tank 14 .
[0015] A calibrated site gauge 50 is provided on tank 14 with a calibrated scale to indicate the amount of water in tank 14 . This allows accurate measurement of the volume of water removed from a well.
[0016] During groundwater sampling, a typical protocol is followed in which three well volumes are removed prior to collecting a sample. A well volume is the amount of water standing in the casing. Typically, monitoring wells are constructed of 2-inch PVC screen and casing. A typical monitoring well may have 5 to 7 feet of water in the casing. Thus a 2-inch casing will contain approximately 0.16 gallons per linear foot of casing. This means that a typical well, assuming seven feet of water in the casing, will contain approximately 1.12 gallons of water. Accordingly, 3.36 gallons must be removed prior to sampling. In the preferred embodiment, tank 14 has a 13-gallon capacity which allows for sampling of three typical wells before emptying the tank. However, other sized tanks may be used. For example, a three to four gallon tank may be used to allow the sampling system to easily fit in the trunk of a car.
[0017] Referring to FIGS. 2 and 3, groundwater sampling system 10 is shown mounted to a 2-wheel cart 52 . Cart 52 includes a handle 54 and pneumatic tires 56 . Air pump 12 along with valve 36 , filter/moisture separator 46 and pressure gauge 48 , including the connecting lines and wiring, are contained in housing 58 which is mounted to cart 52 above tank 14 .
[0018] Housing 58 includes a flat work surface, generally indicated by reference numeral 60 , to serve as a writing/work surface. A small cooler and storage container 62 may be attached to cart 52 to hold samples and supplies. Most groundwater samples must be placed on ice immediately after collection to prevent volatile compounds or solvents from evaporating.
[0019] Groundwater sampling system 10 is sized to fit easily through doors and gates and of a weight of approximately 70 pounds so that it may be easily loaded, unloaded and used by one person. Additional attachments may be used including flow meters for micropurging, for example. At some sampling sites micropurging is conducted where monitoring wells are evacuated at very low rates until some measurement parameter such as pH, specific conductance, or temperature has stabilized. A flow meter and necessary sensors may be attached to the sampling system 10 to measure the flow and other parameters.
[0020] It is to be understood that while certain now preferred forms of this invention have been illustrated and described, it is not limited thereto except insofar as such limitations are included in the following claims. | A portable groundwater sampling system utilizing an air pump in combination with a sampling tank, valves, and a pressure gauge to sample a liquid from a below ground surface monitoring well. The system includes a portable power supply for energizing the air pump and is mounted on wheels for mobility. The system also may include a flat work surface and a storage container. | 4 |
FIELD OF THE INVENTION
[0001] The present invention relates to a biodegradable fibrin based composition (in the following also designated as “bone void filler composition” or “bone void filler”) for injection into osseous defects or voids, which can be the result of osteoporosis, surgery, bone cysts, tumor removal or traumatic bone injury.
BACKGROUND OF THE INVENTION
[0002] There are several examples of injectable bone void fillers in the literature. WO 95/21634 discloses a biomaterial for the resorption substitution of bony tissue. The composition is injectable and comprises calcium phosphate particles in a liquid phase comprising carboxymethylcellulose. U.S. Pat. No. 6,287,341 details a method for repairing an osseous defect wherein two calcium phosphates are mixed with a buffer to provide a paste or putty which is applied to the defect. The putty hardens in the defect due to a chemical reaction. WO 00/07639 discloses a calcium cement for injection into osseous defects. The cement is based on mono basic calcium phosphate monohydrate and beta tricalcium phosphate and may further comprise a biopolymer. Following injection the calcium phosphate cement requires setting. US-patent 2004048947 details an injectable composition for a bone mineral substitute material with the capability of being hardened in a body fluid in vivo, which hardens during the surgery. US-patent 2004101960 details an injectable bone substitute material comprising a mix of living cells within a composition which comprises a soft matrix or a composition which comprises a setting material. The soft materials listed in this patent include collagen gels, gelatin, alginates, agarose, polysaccharides, hydrogels and viscous polymers. It is also mentioned that it is possible to employ commercial fibrin glues such as TissuCol (Baxter) or Beriplast (Aventis) but they are not preferred. Recently there have been a number of injectable bone void fillers that have received 510(k). Of these, Jax-TCP (Smith & Nephew) and Tricos T (Baxter) deliver granules of calcium phosphates in a bio-gel which are applied as a putty/paste.
[0003] The current practice is to fill bone voids with either a bone graft (auto or allograft), bone graft substitutes, a bone cement such as polymethylmethacrylate (PMMA) or injectable calcium salt void fillers. Autografts are the ‘gold standard’ choice for this application but there are issues with donor tissue limitations, trauma, infection and morbidity. There are a number of additional problems that face allografts, including the risk of disease transmission and immunogenicity. Both auto- and allografts display loss of biological and mechanical properties due to secondary remodeling. It is these limitations that have prompted interest in alternative materials to bone grafts (Parikh S. N., 2002, J. Postgrad. Med. 48:142-148).
[0004] PMMA is a non-resorbable polymeric material. During its polymerization unreacted monomer, catalyst and low molecular weight oligomers become entrapped in the polymer. These chemicals have the potential to leach out of the material resulting in localized cytotoxic and immunological responses. PMMA polymerization has a high exothermicity that can potentially cause heat necrosis. This exothermicity also limits the ability of PMMA to incorporate any pharmacological or chemotherapeutic agents. PMMA leakage from a defect can result in very serious complications including compression of adjacent structures (requiring further surgery) and/or embolism.
[0005] As indicated above, there are a number of calcium salt based “injectable void fillers” in the prior art. However moldable pastes also come under this heading. Putties and pastes require surgical placement of a defect. In practice this requires the defect to be surgically revealed. Unfortunately the larger the defect the larger the surgical wound site (US-patent 2005136038). Another major complication with calcium salts is their requirement to for setting in vivo. This is usually achieved by chemical reaction. Thus any biologics and pharmaceutics incorporated in the filler such as cells and pharmacological agents can potentially be damaged. Furthermore, if the filler is too “fluid” it can leak out of the defect into adjacent spaces leading to compression of structures. Leakage from defects proximal to joints can potentially impair the joints function.
[0006] Requirements for a calcium salt composition intended for delivery via the percutaneous route have previously been detailed in WO 95/21634. These include that the material should be sterilizable, must be non-toxic in vitro, the rheology must be such that it permits injection, it must be easy to use and it must have a strong mineralization front.
[0007] Thus, a strong need exists for new injectable bone void fillers which can be sterilized, show a low potential toxicity and a low tendency for leakage, are biodegradable, have a rheology that permits injection and are easy to use.
[0008] Therefore, it is an object of the present invention to provide new injectable void bone fillers for injection into osseous defects or voids resulting, for example, from osteoporosis, surgery, bone cysts, tumor removal or traumatic bone injury.
SUMMARY OF THE INVENTION
[0009] The present invention relates to a micro-porous injectable fully resorbable fibrin-based composition as bone void filler, which is resorbed and replaced with bone during the healing process. Said bone void filler composition of the present application exhibits characteristics, such as mechanical properties typically seen in elastomers and mechanical stability, superior to fibrin alone. According to the present invention, a variety of properties of said bone void filler can be effectively fine-tuned by adjusting type and content of the particles as well as of the plasticizer contained in said bone void filler composition.
DETAILED DESCRIPTION OF THE INVENTION
[0010] One aspect of the present invention relates to a multi-component system for an injectable bone void filler composition, comprising:
component (a) comprising fibrinogen; component (b) comprising thrombin; component (c) comprising at least one plasticizer; and component (d) comprising particles having a diameter of about 200 μm or less.
[0015] According to one embodiment of the present invention the components (a) to (d) of the multi-component system as defined above are each present in solution, and wherein at least component (a) is spacially separated from component (b).
[0016] The multi-component system for an injectable bone void filler composition as defined above may further include any other component suitable for e.g. augmenting, strengthening, supporting, repairing, rebuilding, healing or filling a bone, such as osteoinductive agents, growth factors, chemotherapeutic or pharmacological agents, biologically active agents, hardening and/or adhesive compounds and mineral additives. These compounds may be contained in any of the components (a) to (d) of the multi-component system according to the present invention or may be comprised as extra components.
[0017] According to one example of the present invention, the fibrinogen component (a) of the multi-component system as defined above may further comprise one or more of extracellular matrix proteins, for example fibronectin, cellular associated proteins, other plasma derived proteins, for example blood clotting factor XIII (FXIII) and proteases, and protease inhibitors, and mixtures thereof. The fibrinogen solution according to the present invention may also include any additive which is comprised in the state of the art for scientific and/or commercially available fibrinogen compositions, for example commercially available fibrinogen solutions.
[0018] The term “fibrinogen” includes not only fibrinogen per se, but also any clot-forming substance, such as clot-forming derivatives of fibrinogen, for example “fibrin 1”.
[0019] The amount of fibrinogen in component (a) of the multi-component system ranges for example from about 10 to about 200 mg/ml, such as from about 30 to about 150 mg/ml or from about 75 to about 115 mg/ml.
[0020] The thrombin component (b) of the multi-component system according to the present invention, may further comprise additional compounds known in the art as well as one or both of the components (c) and (d), particularly the plasticizer component (c). There is no specific limitation in respect to the used thrombin amount. In one example of the present invention, the amount of thrombin in said thrombin component (b) is such that it is at least about 1 IU/ml in the final clotted composition, such as about 30 IU/ml.
[0021] The term “thrombin” includes not only thrombin per se, but also any gelation-inducing or clotting-inducing agent for component (a), for example a physiologically acceptable alkaline buffer system.
[0022] The term “plasticizer”, as used herein, includes any suitable substance useful in modifying the properties of the final clotted composition, for example the viscosity, the elastomeric behaviour or the mechanical stability. In one embodiment of the present invention, the plasticizer of the multi-component system as defined above has a low osmolality and allows fibrin assembly to occur at an appropriate extent.
[0023] In one example of the present invention, the suitable plasticizer of the multi-component system according to the present invention comprises at least one biodegradable, water soluble organic compound.
[0024] As used herein, the expression “biodegradable, water soluble organic compound” further includes all compounds which can be degraded in a biological environment and are at least sufficiently soluble in water, for example at temperatures in the range from about 10 to about 40° C.
[0025] Examples of the plasticizer of the multi-component system as defined above are selected from the group consisting of water-soluble contrast agents, polyethylene glycols, polyvalent alcohols such as glycerol, mono-, di-, tri- and polysaccharides, and any combination thereof.
[0026] In one example of the present invention, the suitable contrast agent of the multi-component system according to the present invention comprises at least one iodine containing organic compound. In a further example of the present invention, organic compounds containing rare earth elements such as gadolinium can be used.
[0027] As used herein, the term “iodine containing organic compound” includes all compounds which contain at least one iodine atom and/or iodine ion, bonded either physically or chemically, for example covalently or coordinatively. The same definition applies mutatis mutandis to the above-mentioned organic compound containing rare earth elements.
[0028] Examples of contrast agents, without being limited thereto, are diatrizoate (meglumine), iodecol, iodixanol, iofratol, iogulamide, iohexol, iomeprol, iopamidol, iopromide, iotrol, ioversol, ioxaglate and metrizamide and mixtures thereof.
[0029] According to one example of the present invention, the amount of plasticizer in component (c) is such that it ranges from about 10 to about 80% w/v, such as from about 15 to about 60% w/v or from about 20 to about 40% w/v, in the final clotted composition.
[0030] The term “particle” includes any type of particle shape or form known in the art, for example spherical, angular or hollow.
[0031] In one embodiment of the present invention, the particles of the multi-component system according to the present invention are biodegradable and/or biocompatible, non-toxic, non-watersoluble, inorganic and/or organic. The particles comprise, for example, substances selected from the group consisting of calcium salts such as tricalcium phosphate, alpha-tricalcium phosphate, beta-tricalcium phosphate, calcium phosphate, a polymorph of calcium phosphate, hydroxyapatite, calcium carbonate, calcium sulfate, polymeric compounds such as polylactide, polyglycolide, polycaprolactone, polytrimethylene carbonate, polyethylene glycol and random or ordered copolymers thereof, biodegradable or biocompatible glasses and ceramics and any combination thereof. In one example, the particles are selected from the group consisting of tricalcium phosphate, alpha-tricalcium phosphate, beta-tricalcium phosphate and calcium phosphate and mixtures thereof, having a Ca/P ratio in the range of about 1.5 to about 2. The particles of the present invention further include all commercially available compounds and/or mixtures known in the art to be used within the meaning of component (d). According to another example, said particles of the multi-component system of the present invention have a diameter of less than about 100 μm, for example less than about 50 μm. In one specific example of the present invention the amount of the particles in component (d) ranges from about 1 to about 50% w/w, such as from about 10 to about 45% w/w or from about 30 to about 40% w/w in respect to the final clotted composition.
[0032] According to one embodiment of the present invention, the amount of fibrinogen in component (a) of the multi-component system as defined above ranges from about 10 to about 200 mg/ml, the amount of thrombin in component (b) is such that it is at least about 1 IU/ml in the final clotted composition, the amount of plasticizer contained in component (c) is such that it ranges from about 10 to about 80% w/v in the final clotted composition, and the amount of the particles in component (d) ranges from about 1 to about 50% w/w in respect to the final clotted composition.
[0033] According to a specific example of the present invention, the amount of fibrinogen in component (a) of the multi-component system as defined above ranges from about 75 to about 115 mg/ml, the amount of thrombin in component (b) is such that it ranges from about 25 IU/ml to about 50 IU/ml in the final clotted composition, the amount of plasticizer contained in component (c) is such that it ranges from about 30 to about 50% w/v in the final clotted composition, and the amount of the particles in component (d) ranges from about 30 to about 40% w/w in respect to the final clotted composition.
[0034] In another embodiment of the present invention, the multi-component system for an injectable bone void filler composition, comprises:
component (a) comprising fibrinogen; component (b) comprising thrombin; component (c) comprising at least one plasticizer; and component (d) comprising particles having a diameter of about 200 μm or less;
wherein one or more or all of the components (a) to (d) are present in a solid form.
[0039] The multi-component system according to the present invention may contain the components either in form of a solution or of a dispersion or of a solid, for example as a lyophilisate, or any combination thereof. Further, the components in said multi-component system may be present in containers suitable for storage, transportation or use of said multi-component system. The containers usable in the multi-component system according to the present invention are not limited in any way but include containers of any size, material or shape, for example vials or syringes.
[0040] Moreover, the components of said multi-component system may for example be contained in different containers or may be present in the same container in any combination, for example as a combination of components (b) and (c) in one container and of components (a) and (d) each in different containers.
[0041] According to the present invention, the containers may for example contain one or more components as a solid, as well as a solvent separated from said components by a separation means in said container, wherein a solution of the respective one or more components can be prepared by breaking or removing said separation means. The components (a) to (d) of the multi-component system of the present invention may be also present as a ready-to-use mixture.
[0042] Moreover, said components (a) to (d) present in one or more containers may also be part of a kit, comprising the multi-component system as defined above. The kit may further comprise any additional compound usable in the multi-component system of the present invention, for example auxiliary agents, buffer salts or buffer solutions. The kit as defined above may also contain means for mixing the components, for example syringes, Luer adapters, tubes, extra containers, etc.
[0043] Another aspect of the present invention relates to an injectable bone void filler composition, comprising:
component (a) comprising fibrin; component (b) comprising thrombin; component (c) comprising at least one plasticizer; and component (d) comprising particles having a diameter of about 200 μm or less.
[0048] According to one example of the present invention, the injectable bone void filler composition is prepared from the multi-component system as defined above, for example by mixing the components of said multi-component system together and/or homogenizing said components. The preparation of the injectable bone void filler composition can be carried out at any suitable temperature, such as in the range from about 18 to about 37° C., for example at 25° C.
[0049] Moreover, the injectable bone void filler composition as defined above may further include any other component suitable for e.g. augmenting, strengthening, supporting, repairing, rebuilding, healing or filling a bone, such as osteoinductive agents, growth factors, chemotherapeutic or pharmacological agents, biologically active agents, hardening and/or adhesive compounds and mineral additives. These compounds and/or agents can be chemically attached to the matrix, adsorbed on the particulate component, for example on calcium salt containing particles, trapped in the fibrin matrix or contained as a free molecule/drug particle, for example a powder.
[0050] The components (b) to (d) of the injectable bone void filler composition according to the present invention are the same as defined for the multi-component system characterized above.
[0051] The term “fibrin” does not only refer to fully coagulated fibrinogen but further includes any mixture of fibrin and fibrinogen which may occur during formation of fibrin from fibrinogen using thrombin and, thus, includes any ratio of fibrinogen/fibrin and any grade of gelation and/or clotting conceivable as long as it has no negative impact on the final composition injected into the non-mineralized or hollow portion of a bone. The fibrin component (a) of the injectable bone void filler composition of the present invention further includes fibrin with only a small amount of fibrinogen or without any fibrinogen left in said fibrin. Moreover, the term “fibrin” further includes any partly or fully gelled or clotted form of component (a) as defined above.
[0052] According to one example of the present invention, the amount of fibrin in said fibrin component (a) of the injectable bone void filler composition as defined above ranges from about 5 to about 100 mg/ml, such as from about 15 to 65 mg/ml or from about 30 to 65 mg/ml in the final clotted composition.
[0053] According to another example, the amount of fibrin in said fibrin component (a) of the injectable bone void filler composition of the present invention ranges from about 5 to about 100 mg/ml in the final clotted composition, the amount of thrombin in component (b) is at least about 1 IU/ml in the final clotted composition, the amount of plasticizer contained in component (c) ranges from about 10 to about 80% w/v in the final clotted composition, and the amount of particles in component (d) ranges from about 1 to about 50% w/w in respect to the final clotted composition.
[0054] According to the present invention, the injectable bone void filler composition as defined above is in a gelled or clotted state and has a viscosity suitable for injecting into a non-mineralized or hollow portion of a bone, and may be applied in a pre-clotted liquid, gelled or clotted state.
[0055] As used herein, the term “gelled” means any state of elevated viscosity when compared to the initial state. This can be observed for example in the formation of fibrin from fibrinogen or in a finely dispersed system of at least one solid phase and at least one liquid phase, such as a colloid. Further, the term “gelled” includes all states of gelation known in the art.
[0056] The term “clotted” means, for example, a gel comprising fibrin and includes any kind of coagulation state known in the art.
[0057] According to the present invention, the viscosity of the injectable bone void filler composition depends on the application, i.e. the bone disorder to be treated, and is adjusted within the common knowledge of a person skilled in the art. For example, an injectable composition for filling bone cysts contains a lower fibrin amount and/or a lower amount of calcium salt-containing particles. An injectable composition for replacing non-mineralized portions of the bone contains a higher fibrin amount and/or a higher amount of calcium salt-containing particles. According to one example of the present invention, the viscosity of the bone void filler composition of the present invention ranges from about 100 mPas to about 1000 Pas.
[0058] Another aspect of the present invention, relates to a method of filling a void in a bone in a patient suffering from a bone disorder, comprising injecting the injectable bone void filler composition as characterized above, into a non-mineralized or hollow portion of said bone.
[0059] As used herein, the term “patient” means a subject suffering from a bone disorder and includes mammals, particularly human beings.
[0060] The method of filling a void in a bone as defined above is not limited to a certain mode of treatment and includes any kind of injection technique, for example percutaneous injection. According to a specific example of the present invention, the method for filling a void in a bone as defined above is percutaneous bone augmentation and comprises vertebroplasty and kyphoplasty.
[0061] Moreover, the method of filling a void in a bone according to the present invention can be used for strengthening, supporting, repairing, rebuilding, healing, augmenting or filling a bone, for example a bone in a human suffering from a bone disorder including trauma or fracture. Another field of application is, for example, spinal fusion.
[0062] Examples of such bone disorders are osteoporosis, osteoporotic bone fractures, traumatic fractures of any type of bone, benign and malignant lesions and surgically created defects.
[0063] The bone void filler composition according to the present invention advantageously meets all the requirements for a composition usable in the treatment of osseous defects or voids. The bone void filler composition is sterilizable, is easy to use and the rheology of it does permit injection. Surprisingly, If calcium salts are used as the particulate component in the composition it is possible to achieve a strong mineralization front which is highly beneficial in the healing process of a bone disorder as described above. Furthermore, the bone void filler of the present invention is fully resorbable and is replaced with bone during the healing process. Advantageously, said bone void filler composition shows substantially no exothermicity and exhibits mechanical properties, such as mechanical behaviour typically seen in elastomers, superior to fibrin alone. All essential properties, for example viscosity, mechanical stability, resorbability, etc., can be surprisingly effectively fine-tuned by adjusting type and content of the particles as well as of the plasticizer contained in said bone void filler composition, within the claimed scope of protection.
BRIEF DESCRIPTION OF THE DRAWINGS
[0064] FIG. 1 : Rheological analysis of compositions containing 30% of the plasticizer iodixanol and 75 IU/ml thrombin. The effect of increasing calcium phosphate in the composition is clearly seen. Complex viscosity is plotted on a linear scale.
[0065] FIG. 2 : Differences in complex viscosities as a result of increasing concentration of plasticizer and/or the particulate content.
[0066] FIG. 3 : The delivery of the injectable bone void filler according to the present invention into a bone void in the long bone of a rabbit. The catheter is inserted and the void is filled. Following the procedure, the catheter is easily removed.
[0000] The present invention will be further illustrated in the following examples, without any limitation thereto.
EXAMPLES
Example 1
Preparation of Bone Void Filler Composition Containing Fibrin, Glycerol and Calcium Phosphate
[0067] Materials:
Fibrin Freeze dried fibrinogen powder reconstituted with sealant aprotinin solution to a total clottable protein concentration solution of 91 mg/ml. Iodixanol 5-[acetyl-[3-[acetyl-[3,5-bis(2,3- dihydroxypropylcarbamoyl)-2,4,6-triiodo-phenyl]-amino]-2- hydroxy-propyl]-amino]-N,N′-bis(2,3-dihydroxypropyl)- 2,4,6-triiodo-benzene-1,3-dicarboxamide Iohexol 5-(acetyl-(2,3-dihydroxypropyl)amino)-N,N′-bis(2,3- dihydroxypropyl)-2,4,6-triiodo-benzene-1,3-dicarboxamide Particles Tricalcium phosphate particles (TCP), 35 μm, spherical (Plasma Biotal, Derby UK) Thrombin Freeze dried thrombin powder reconstituted with 5 ml of 500 IU/ml thrombin buffer, to a concentration of 500 IU/ml. Thrombin 40 mM CaCl 2 in H 2 O Buffer
[0068] A 40% plasticizer (gycerol) and 10 IU/ml thrombin solution is prepared in a thrombin dilution buffer (40 mM CaCl 2 in double distilled water). The solution is then homogenised. The solution is centrifuged to remove bubbles and sterilised by filtering through a 0.22 μm filter. The fibrinogen is mixed with thrombin/plasticizer in a 1:1 ratio (therefore the plasticizer concentration in the gelled clot is halved). For this 2 ml of the glycerol/thrombin solution is transferred to a 5 ml syringe. 2 ml of fibrinogen (91 mg/ml) is transferred to a separate 5 ml syringe. The particles (ca. 2 μm) are incorporated as percentage weight of the final clot volume (w/v). These are weighed and placed into another 5 ml syringe.
[0069] The syringes containing the particles and the thrombin are connected via a Luer adapter and the thrombin/glycerol and particles homogenised by transferring the contents from syringe to syringe thoroughly.
[0070] The syringes containing the thrombin/glycerol/particles and the fibrinogen are connected via a Luer adapter and the contents homogenised.
[0071] The material remains liquid for approximately 1 minute. During this time it can be injected into the defect or alternatively after a few minutes it can be delivered as a pre-formed gel.
Example 2
Preparation of Bone Void Filler Composition Containing Fibrin, a Contrast Agent and Calcium Phosphate
[0072] Either an 80% or a 60% plasticizer (contrast agents iodixanol or iohexol) and a 75 IU/ml thrombin solution is prepared in a thrombin dilution buffer (40 mM CaCl 2 in double distilled water) The solution is then homogenised. The solution is centrifuged to remove bubbles and sterilised by filtering through a 0.22 μm filter. The fibrinogen is mixed with thrombin/contrast agent (CA) in a 1:1 ratio (therefore the plasticizer concentration in the gelled clot is halved to either 40 or 30%). For this 2 ml of the thrombin/contrast agent solution is transferred to a 5 ml syringe. 2 ml of fibrinogen (91 mg/ml) is transferred to a separate 5 ml syringe. The particles (ca. 2 μm) are incorporated as percentage weight of the final clot volume (w/v). These are weighed and placed into another 5 ml syringe.
[0073] The syringes containing the particles and the thrombin are connected via a Luer adapter and the thrombin/CA and particles homogenised by transferring the contents from syringe to syringe thoroughly.
[0074] The syringes containing the thrombin/CA/particles and the fibrinogen are connected via a Luer adapter and the contents homogenised.
[0075] The material remains liquid for approximately 1 minute during this time it can be injected into the defect or alternatively after a few minutes it can be delivered as a pre-formed gel.
[0076] The viscosities of the respective clots with different concentrations of contrast agents and of TCP can be taken from FIG. 1 . Rheological data of compositions containing of iodixanol as plasticizer and increasing amounts of calcium salts can be taken from FIG. 2 .
Example 3
Use of the Bone Void Filler for Filling a Bone Void in the Long Bone of a Rabbit
[0077] The injectable bone void filler was prepared according to Example 2.
[0078] The bone marrow is removed from a rabbit long bone to form a hollow bone. Then the injectable bone void filler is injected into the hollow bone using a plastic catheter. After the procedure, the plastic catheter is easily removed from the hollow portion of said bone (cf. FIG. 3 ).
Example 4
In Vivo Studies of the Injectable Bone Void Filler Composition in Sheep
[0079] The medial fascia of the tibia shaft is excised and the tibia is exposed. A plate is contoured to the shaft and fixed to the bone using screws. The plate is removed again and a standardized 1 cm full thickness defect is created. The segment is removed, the plate is repositioned and the screws are reinserted. Thereafter, the injectable bone augmentation composition is filled into the defect and the wound is closed by suture.
[0080] The animals are followed up for 4, 8 and 12 weeks (X-ray evaluation). At the 12 weeks timepoint the animals are sacrificed and the tibia is extracted for final analysis (μCT and histology).
[0081] The bone void filler composition and the resulting clots according to the present invention exhibited excellent properties. | The present invention relates to a biodegradable fibrin based composition for injection into osseous defects or voids, which can be the result of osteoporosis, surgery, bone cysts, tumor removal or traumatic bone injury. | 0 |
BACKGROUND OF THE INVENTION
This invention relates to a control device for a periodically oscillating member, the amplitudes of which in opposite directions are different from each other when a predetermined balanced condition is not maintained.
Frequently, it is necessary to adapt the drive of an oscillating member to the average speed of another drive unit. For example, if the input of material into a machine is continuous or discontinuous and the oscillating member serves to process the material in the machine or to discharge the material from the machine, it is frequently necessary to maintain the speed of the periodic oscillation movement such that it corresponds to the average speed of the input of material so that the amount of material discharged from the machine consistently corresponds on the average to the amount of material supplied to the machine.
If the amplitude of the oscillating member in one direction surpasses and in the other direction falls short of the predetermined average speed of the drive unit, the oscillation range of the oscillating member is caused to migrate due to the incorrect drive speed. The deviation from the correct drive speed is cumulative so that the oscillating range is altered. If limit switches are positioned at the opposite predetermined limits of the oscillation range, a signal will be emitted by one of the limit switches each time the oscillating member exceeds the position of the one limit switch which could serve to adjust the speed of the drive unit. However, the limit switch would also emit a signal when the oscillating member stopped and did not exceed the position of the limit switch causing the speed of the drive unit to be changed even though such change was not warranted. If, when simple limit switches are used, a pulse clock is transmitted via a closed limit switch so that adjusting pulses are supplied to the drive unit, too many adjusting pulses will be transmitted over too long a period of time with each amplitude so that the control circuit tends to cause overmodulation which is a disadvantage.
It is an object of the present invention to provide a simple and economically constructed control device for use with a periodically oscillating member which does not have the disadvantages of overcontrol and undercontrol oscillations.
SUMMARY OF THE INVENTION
The apparatus of the present invention includes at least two sensors located near opposite ends, respectively, of the path of the periodically oscillating member. The sensors are movably mounted such that, when the amplitude of the periodically oscillating member extends beyond a predetermined oscillating range, one of the sensors will be moved by the periodically oscillating member to the final position of the member. The sensors do not hamper the movement of the oscillating member. Upon reaching the end of the oscillation, the influence of the oscillating member on the sensor is terminated. The electrical correction signal emitted by the sensor is only generated during the advance travel of the oscillating member.
To avoid generating sensor signals in the normal predetermined oscillating range of the oscillating member, which range is maintained when the drive speed of the oscillating member is exactly adjusted to the predetermined average speed, an auxiliary sensor may be stationarily mounted at a predetermined location along the path of the oscillating member adjacent each movable sensor which auxiliary sensor serves to suppress signals from the corresponding movable sensor as long as the oscillating member is within the predetermined oscillating range. The sensors may be arranged to be ineffective in specific oscillating ranges.
The return travel of each of the movable sensors to its starting or normal position may be accomplished by the oscillating member during movement in the opposite direction. The two movable sensors may be rigidly coupled at a predetermined distance from each other so that each sensor during its travel with the oscillating member causes the other sensor to move in the same direction. Thus, when one movable sensor is moved by the oscillating member, the opposite movable sensor is moved to the same extent.
In another embodiment, each of the movable sensors is biased in the direction of its starting or normal position. A retaining device serves to temporarily retain each sensor at the position to which it is moved by the oscillating member so that the sensor does not immediately return to its starting position upon movement of the oscillating member in the opposite direction. The retaining device may be released by the oscillating member during its movement in the opposite direction allowing the sensor to return to its starting position. The retaining device may consist of a pivotally mounted rack fitted with a plurality of teeth so that the sensor will be retained by one of the teeth at the position at which the oscillating member stops. A cam bar near the opposite end of the pivotally mounted rack is arranged to be moved by the oscillating member during its movement in the opposite direction releasing the retained sensor from the rack and allowing the sensor to return to its starting position. In this embodiment the sensors will always be at predetermined starting positions when they are contacted by the oscillating member.
In a further embodiment, the sensors may be arranged on pivoted arms such that they move along arcuate paths rather than along straight paths. In this embodiment the two pivoted arms include projections, and the opposite ends of a rod are pivotally mounted on the projections such that the pivoted arms are in parallel alignment with each other. The angle sectors covered during movement of the coupled sensors, however, are unequal. The returning sensor moves more quickly towards its starting position than the sensor moved by the oscillating member which emits adjustment pulses to the drive unit. This arrangement wherein the returning sensor moves more quickly to the starting position than the other sensor being moved away from the starting position by the oscillating member has the advantage that a desired average value is obtained automatically and the position of the oscillation range of the oscillating member remains within predetermined limits.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is a schematic side view of the periodically oscillating member and a first embodiment of the control device;
FIG. 2 is a block diagram showing the control system and drive unit for the periodically oscillating member;
FIG. 3 is a schematic partial side view of the periodically ocillating member and a second embodiment of the control device incorporating an auxiliary sensor;
FIG. 4 is a schematic front view of the arrangement shown in FIG. 3;
FIG. 5 is a schematic side view of the periodically oscillating member and a third embodiment of the control device;
FIG. 6 is a schematic plan view of the periodically oscillating member and a fourth embodiment of the control device; and
FIG. 7 is a schematic side view of a fleece layer with which the control device may be used.
DETAILED DESCRIPTION OF INVENTION
Referring to FIG. 1, two sensors 11, 12 are slidably mounted on a guide rail 13 and are connected to each other by a rigid bar 18. The guide rail 13 extends parallel to the path of oscillating member 15 as indicated by the double arrow 14. The oscillating member 15 has a projecting arm 16 with an arm 17 extending in opposite directions from the arm 16. The arm 17 is arranged to enter and actuate sensors 11 and 12 as the oscillating member 15 moves along its path.
The sensors 11, 12 are mechanical or electrical switches which respond to the presence of an element within a predetermined area. Examples of a sensor include a simple mechanical limit switch, an electronic approximation initiator, a light barrier, etc.
An example of an electrical circuit for the sensors and control system is shown in FIG. 2. Sensors 11, 12 serve to operate switches 11", 12". Alternatively, sensors 11, 12 may themselves be switches 11", 12". Both switches 11, 12 are connected with a pulse generator 19 generating pulses with adjustable frequency and constant amplitude. When one of the sensors 11, 12 responds to the presence of the oscillating member 15, the corresponding switch 11", 12" is closed and the control device 20 receives at one of its inputs a pulse number which corresponds to the closing time of the corresponding switch. The pulse number may be converted by an integrator or a counter and a subsequently connected DIA converter to an electrical direct voltage which is used, in a known manner, to increase or reduce the speed of drive motor 21 which drives the oscillating member 15. A pulse sequence supplied to the control device 20 via switch 11" causes a reduction in the speed of the motor 21, and a pulse sequence supplied to the control device via switch 12" causes an increase in the speed of the motor 21.
When, in the arrangement illustrated in FIG. 1, the oscillating member 15 moves to the left side, arm 17 actuates sensor 11 causing the corresponding switch to close. If oscillating member 15 moves further to the left than the position of sensor 11, both sensors 11 and 12 will be pushed to the left along guide rail 13 to a position where the oscillating member 15 finally stops. Oscillating member 15 then moves in the opposite direction to a point where arm 17 actuates the opposite sensor 12. If the oscillating member 15 continues to move to the right, the sensors 11 and 12 will also be moved to the right along guide rail 13 to a position where the oscillating member 15 finally stops.
FIGS. 3 and 4 illustrate a variation of the embodiment illustrated in FIG. 1 in that auxiliary sensors are provided in addition to sensors 11, 12 (only auxiliary sensors 11' is shown). The auxiliary sensor 11' is mounted in a fixed position on guide rail 13, the fixed position being adjacent the normal position of sensor 11. This normal position of sensor 11 is the position at which the sensor 11 may be actuated but is not moved further along the guide rail 13 by the oscillating member 15 such that no speed adjustment of the drive for the oscillating member 15 is required. Unlike sensor 11, auxiliary sensor 11' is designed as a rest contact. It includes a switch which in non-excited condition is closed and in excited condition is open. The auxiliary sensor 11' is included in the electrical circuit to prevent pulses reaching the control device 20 via sensor 11 as long as the arm 17 actuates auxiliary sensor 11'. The adjustment pulses arriving via sensor 11 only become effective when the sensor 11 has been pushed past a predetermined position by the oscillating member such that the arm 17 no longer actuates auxiliary sensor 11'. This position can be adjusted by displacement of the auxiliary sensor 11' on the guide rail 13.
Although the rigid bar 18 is shown as being non-adjustable, it may consist of several members so that its length may be adjusted. This may be achieved by arranging the members telescopically or by including a threaded sleeve.
Referring to FIG. 5, the sensors 11, 12 are mounted for independent displacement along guide rail 13. The sensors 11, 12 are not connected to each other by a bar. Tension springs 20, 21 extend respectively between the sensors 11, 12 and elements 22, 23. The tension springs 20, 21 bias the sensors 11, 12 towards starting or normal positions of the sensors, respectively.
The sensors 11, 12 are retained in the position to which they are pushed by oscillating member 15 by pivotally mounted rods 24', 25' having saw-teeth or racks 24, 25, respectively. Thus, as sensor 11 is pushed to the left, the rack 24 acts as a ratchet retaining the sensor 11 at the position to which it is pushed by oscillating member 15 after which oscillating member 15 travels in the opposite direction.
Rods 24' and 25' are pivoted about pivot points 26 and 27, respectively. Each rod 24, 25 opposite the saw-teeth includes a cam surface 28 which is actuated by oscillating member 15. When the oscillating member 15 presses against a cam surface 28, the opposite end of the rod 24', 25' containing the saw-teeth 24, 25 is pivoted downwardly releasing the retained sensor. The tension spring 20, 21 immediately returns the sensor to its starting or normal position. Due to the fact that the length of the rod 24', 25 containing the cam surface 28 on one side of the pivot point 26, 27 is longer than the length of the same rod containing the saw-teeth 24, 25 on the opposite side of the pivot point, the saw-teeth 24, 25 are biased upwardly providing the ratchet action due to gravitation, avoiding the need for additional springs.
In the arrangement illustrated in FIG. 5, the sensor 11 returns to its starting or normal position when oscillating member 15 presses against the cam surface 28 to the right. This occurs before arm 17 actuates sensor 12.
Referring to FIG. 6, sensors 11, 12 are mounted on pivot arms 30, 31, respectively, which are pivoted about stationary vertical axes 32, 33. Thus, each sensor, when moved by oscillating member 15, follows an arcuate path.
The two pivot arms 30, 31 include projections 35, 36, respectively, extending in opposite directions. A rod 34 is pivotally mounted at opposite ends to the projections 35, 36. The length of the rod 34 is adjustable and is so adjusted that the pivot arms 30, 31 extend parallel to each other when the pivot arms are located at their extreme positions, as for example at positions A, a, respectively, as illustrated in FIG. 6. Due to the fact that the projections 35, 36 extend in opposite directions away from each other, the rod 34 does not extend constantly in parallel to a line drawn between the axes 32, 33.
When sensor 11 is moved from position A to position B by oscillating member 15, sensor 12 is moved from position a to position b. It will be noted, however, that sensor 12 moves through a greater distance and thus more quickly than does sensor 11 which has also been moved and transmits the adjustment pulses for controlling the drive speed of the oscillating member 15. When sensor 11 moves to position C or E, sensor 12 is moved to position c or e. The angular sector covered by sensor 12, however, becomes smaller while the size of the angular sectors through which the sensor 11 is moved remains constant. It will be appreciated that conversely when sensor 12 is moved by oscillating member 15 sensor 11 will initially move more quickly to its starting or normal position than sensor 12. It has been found that this arrangement, wherein the returning sensor more quickly approaches its starting position, has a favorable influence on control of the drive speed of the oscillating member 15.
FIG. 7 illustrates schematically a working example of a machine in which the control device of the invention may be used. The machine is adapted for laying non-woven fabrics. Reference is made to copending application Ser. No. 775,022 filed Mar. 7, 1977 by Hille which copending application is incorporated by reference. The machine comprises a conveyor belt 40 driven at constant speed for supplying fibrous material from a carding machine or the like. The non-woven material is laid uniformly on a laying belt 41 extending transversely to the conveyor belt 40. This is accomplished by a laying device which oscillates along a path transverse to the laying belt 41 laying the fleece uniformly on the belt.
The non-woven material on conveyor belt 40 passes around guide roll 42 and drops on a storage belt 43 passing about guide rolls 44, 45. At the end of the storage belt 43, the fibrous material drops on a further conveyor belt 46 running over one of two laying rolls 47, 48. The laying rolls 47, 48 rotate anti-clockwise and form therebetween a laying gap through which the fibrous material drops on the laying belt 41. The two laying rolls 47, 48 are rotatably attached on a carriage 49 which moves to and fro along a path transverse to the laying belt 41. Electric motor 21 drives a drive chain 50 to which the carriage 49 is attached to move the carriage 49 along the transverse path. The motor 21 is switched periodically between forward and reverse directions to advance and return the carriage 49. The carriage 49 constitutes the periodically oscillating member 15 and the speed of the motor 21 is controlled by the circuit shown in FIG. 2.
Belt 46 moves over two guide rolls 51, 42 and over another guide roll 53 supported by a balancing carriage 54. Thereafter the belt moves further over roll 55 to carriage 49.
The two rolls 44 and 45 of the storage belt 43 and rolls 51, 52, 55 of the conveyor belt 46 are supported by a storage carriage 57 arranged to move horizontally along guide means (not illustrated).
The conveyor belt 46 is driven at constant speed by roll 53. The roll 53 is driven synchronously with the rotation of roll 52 of the feeding conveyor via a transmission unit (not illustrated) so that the belt 46 has the same speed as the conveyor belt 40.
The speed at which the carriage 49 oscillates along its path about the laying belt 41 must correspond on the average to the speed of the conveyor belt 40. The carriage 49 moves to and fro constantly and consequently must periodically be slowed or accelerated since a constant uniform speed, though desired, cannot be achieved. To insure that the fleece material is laid uniformly on the laying belt 41 a balancing carriage 54 is provided which moves horizontally, the operation of which will be explained hereinafter.
To measure the prevailing speed of the laying carriage 49, a measuring chain 58 is provided which extends parallel to the drive chain 50 and is secured between two stationary points. Freely rotatable gears 59, 60 are mounted on the axles of the laying rolls 47, 48 and are driven by the measuring chain 58. The speed of the gears 59, 60 corresponds to the travel speed of the laying carriage 49. Gear 59 (via a free-wheel) and gear 59' (via a clutch engaged at the points where the laying carriage 49 reverse direction) drive further gears (not illustrated) through a control chain 60 which is always driven in the same direction with the advance and the return of the laying carriage 49.
Control of the movements of the storage carriage 57 and of the balancing carriage 54 is maintained by control chain 60. Control chain 60 is driven by a pinion 64 with roll 42 of the feeding conveyor on a common shaft so that the control chain 60 has the same drive speed as conveyor belt 40. The chain 60 subsequently runs about two guide wheels 61, 61' supported at the storage carriage 57 and over the gears of the laying carriage 49. At the outer end of the storage carriage 57 are two other guide wheels 62 and 63, and from there the chain 60 runs back to the drive chain wheel 64 driven by the conveyor belt 40.
The operation of the fleece layer will now be described. The laying carriage 49 moves to and fro along the path about the laying belt 41. When moving to the right from the position shown in FIG. 7, the storage carriage 57 is moved at half the speed of the laying carriage 49 by the control chain 60 of the assembly. The laying carriage is connected via a traction rope 65 running over a guide roll 66 of the storage carriage 57 with the balancing carriage 54 to draw it to the right side. The lower loop of the belt 46 is reduced while the upper loop is increased.
The speed of the laying carriage 49 which is not constant must correspond on the average to the speed of the conveyor belt 40. The control chain 60 is driven at two points, namely, at its upper run by gear 64 with the feeding speed of the fleece and at its lower run by the measuring chain corresponding to the actual speed of the laying carriage 49. If the speed of the carriage 49 is less than the fleece speed, there is formed at the guide rolls 62, 63 a traction force to the right which acts on the storage carriage 57, while no traction force acts at the guide wheel 61. Due to the traction of the belt 46, the balancing carriage 54 is also drawn to the right so that the lower loop of the belt 46 is extended temporarily while the upper loop of the belt is shortened. If the speed of the laying carriage 49 corresponds exactly to the speed of the fleece, no substantial traction takes place in the control chain 60 so that the balancing carriage 54 is not displaced.
The constant braking and acceleration during the to and fro movement of the laying carriage 49 brings about periodic balancing movements of the balancing carriage 54. If the average speed by which the motor 21 is driving the laying carriage 49 is not exactly equal to the speed of belt 40, the movements of the balancing carriage 54 will be either predominantly to the left over those movements to the right or vice versa. To limit the travel of the oscillating balancing carriage 54 the control device of the invention with the sensors 11, 12 is used which, subject to the size of the amplitude in one direction or the other, periodically adjusts the speed of the motor 21.
The present invention is not restricted to the use of the control device for fleece laying machines but may be used generally where the drive speed of an independent drive for a periodic to and fro movement must be adapted to a specific speed, and in cases in which by the control of a parameter the range of the to and fro moving device will be controlled. | A control device is disclosed for controlling the drive means and consequently the oscillation range of a periodically oscillating member particularly when it is necessary to maintain the speed of the periodic oscillation movement such that it corresponds to the average speed of another drive unit. Two movably mounted sensors are located near opposite ends of a predetermined oscillation range of the oscillating member. When either of the sensors senses the presence of the oscillating member beyond the predetermined oscillation range, a signal is generated by the sensor which is transmitted to control means adapted to adjust the speed of the drive means operating the oscillating member. | 3 |
BACKGROUND OF THE INVENTION
The invention relates to a dust and trash removal system for carding machines or cards including a cylinder and carding segments cooperating therewith, said means comprising a mote knife having a blade section whose blade is arranged in a direction opposite to the running direction of the cylinder at a small distance from the surface of the cylinder, as well as a hold-down means arranged in the running direction of the cylinder upstream of the mote knife with a base surface extending substantially in parallel with the surface of the cylinder.
Such a dust and trash removal system is, for instance, known from DE-A-2846109. Dust and trash removal systems of this type are used in carding machines for removing the dirt particles still remaining in the fibers, as well as fiber fragments and shortened fibers. However, it often happens that part of the dirt particles to be discharged remain in the fibers and that fibers which are to be further processed, so-called material fibers, are discharged. As a consequence, the cleaning results are unsatisfactory on the whole.
SUMMARY OF THE INVENTION
It is the object of the present invention to develop a dust and trash removal system of the above-mentioned type in such a manner that in the discharged waste the ratio of dirt particles, fiber fragments and short fibers on the one hand to material fibers on the other hand is improved in such a manner that the amount of discharged good fibers is reduced and the amount of discharged trash, dust and short fibers is increased.
This object is attained according to the invention in that the blade, when being viewed in cross-section, has at least one rounded section with a radius greater than 1 mm.
As for the achievement of the present invention, it has been found that the proportion of discharged good fibers is considerably reduced and the proportion of discharged trash, dust and short fibers is considerably increased at the same time.
It has turned out that it is advantageous when the radius is between 1 and 5 mm and the mote knife is designed as a substantially plate-shaped structure with a contact side for mounting on a carding segment and a front side in parallel therewith, and that the mote knife extends substantially over the whole width of the cylinder.
Furthermore, the blade may have a front side arranged in a direction opposite to the running direction of the cylinder and a back side arranged in the running direction of the cylinder, the front and back sides being possibly interconnected by the rounded section. The front and back sides may here enclose an angle of about 70°. The front side may extend in parallel with the planar extension of the mote knife.
In another embodiment the front side may be inclined by about 10° relative to the planar extension of the mote knife.
The cleaning result may be improved by the front and back sides of the blade passing tangentially into the rounded section.
It has been found to be advantageous to the operation of the dust and trash removal system when the back side of the blade lies in an imaginary plane which encloses an angle of about 10° with a vertical plane relative to the planar extension of the mote knife.
In another embodiment the radius of the rounded section may substantially correspond to the thickness of the mote knife.
To simplify manufacture, the front side of the blade and the front side of the mote knife may be in one plane.
In another embodiment the thickness of the mote knife may be considerably smaller in the area of the blade than in the remaining areas of the mote knife.
In another embodiment the front side which is inclined by about 10° relative to the planar extension of the mote knife may be followed by a section which is inclined in the opposite direction, the front side and the inclined section forming a recess of the mote knife. A plurality of recesses may here also be arranged in waved configuration one after the other on the mote knife.
In an advantageous development of the invention the distance between blade and surface of the cylinder is variable.
Moreover, it has been found to be advantageous when the mote knife is adjacent to one of the carding segments.
To improve the cleaning results, at least one air supply duct may be provided according to the invention with at least one opening which is arranged in a direction opposite to the running direction of the cylinder in front of the base surface of the hold-down means in such a manner that an air current guided through the air supply duct can exit through the opening towards the surface of the cylinder. It has been found that with this kind of air guidance an improved discharge result can already be obtained in the sense of the invention even in cases where mote knives are used whose blades have a radius of less than 1 mm. Separate protection is therefore claimed for the air supply-duct.
In an advantageous development the opening may be arranged near the surface of the cylinder.
Moreover, the air supply channel may be defined by a carding segment and the hold-down means. The air supply duct can thus be implemented in an easy manner. To this end, the hold-down means may comprise a fastening section and a base section adjacent thereto, the base section carrying the base surface at its side facing the cylinder, and the fastening section defining the air supply duct together with the carding segment.
To this end, the fastening section of the hold-down means may be spaced apart from the carding segment, the distance between carding segment and fastening section being adjustable in such a manner that the cross-section of the air supply duct can be varied. The air supply duct may have a substantially rectangular shape when viewed in cross-section. A width of about 10 mm has been found to be optimum during operation. The cross-section of the air supply duct is normally constant over its length, but it is also possible that the air supply duct tapers towards the cylinder surface.
In order to regulate the amount of air passing through the air supply duct, there may be provided an air-supply regulating means for regulating the air current flowing through the air supply duct. To this end, the air-supply regulating means has preferably a tongue which can be moved into the air supply duct such that the cross-section of the air supply duct can be varied.
To obtain an especially simple air regulating means, said means may be designed as a substantially two-dimensional structure whose front section forms the tongue and whose rear section serves to receive fastening elements, and which is displaceably mounted on the upper side of a carding element in parallel with the running direction of the cylinder and can be fixed with the fastening elements above the carding segments. Moreover, the tongue may have an end section which is bent relative to the planar extension of the air-supply regulating means in such a manner that it projects into the air supply duct. The air-supply regulating means as well as the air supply duct advantageously extend over the whole width of the cylinder.
In an advantageous development of the invention the distance between the base surface of the hold-down means and the cylinder can be adjusted. The distance may be set down to zero where dirt discharge no longer takes place. A distance of from 0.25 to 25 mm between the base surface and the cylinder has been found to be advantageous to the operation of the dust and trash removal system.
In an advantageous development of the invention the gap created between the base surface and the cylinder tapers in the running direction of the cylinder.
In another embodiment the base surface of the hold-down means may have a curvature concavely facing away from the surface of the cylinder. It has been found that such a curvature effects an improved dirt discharge result. It has here been found to be of advantage when the base section of the hold-down means has an end section which faces the knife and whose end extends in a direction substantially perpendicular to the surface of the cylinder and away therefrom.
In an advantageous development of the invention, the clear width between the base surface and the blade section is variable. The clear width may here be reduced down to zero where dirt discharge no longer takes place.
Like the mote knife, the hold-down means may also extend over the whole width of the cylinder.
Furthermore, it has been found to be advantageous when the hold-down means is bent from a material whose thickness is considerably smaller than its planar extension. This allows low manufacturing costs on the hand and the formation of a cavity between hold-down means and mote knife on the other hand, with the cavity serving to accommodate a suction means for the good fibers or dust, trash and short fibers. In an advantageous development there is provided a cover between mote knife and hold-down means for forming a suction chamber enclosed by the hold-down means, the mote knife and the cover. The dust, trash and short fibers removal can thus be supplied via the suction chamber and a suction device into a receiving device provided for receiving the dirt particles.
The invention shall now be described in more detail with reference to several embodiment.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 is a lateral view of a carding machine comprising a cylinder, carding segments and the dust and trash removal system of the invention;
FIG. 2 is an enlarged view of the section shown in FIG. 1 and marked by II;
FIG. 3 shows a first embodiment of a mote knife;
FIG. 4 shows a second embodiment of the mote knife;
FIG. 5 shows a third embodiment of the mote knife;
FIG. 6 shows a fourth embodiment of the mote knife;
FIG. 7 shows a second embodiment of a hold-down means.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 diagrammatically illustrates a carding machine 1 comprising a cylindrical drum 2 with a running direction 1, as well as feed rollers 3 and 4 for feeding a fiber material 5, and a take-off roller 6 for removing the carded fiber material 5 from said drum or cylinder 2. Cylinder 2 has an axis 7. Moreover, the carding machine includes a frame 8, which is however only shown in part for the sake of clarity. Apart from the accommodation of drive motors, frame 8 serves to support cylinder 2, as well as feed rollers 3 and 5 and take-off roller 6. FIG. 1 additionally shows mounting means 9 for mounting carding segments 10. The mounting means 9 are of curved configuration and stationarily arranged near the cylinder, i.e., near the front side thereof.
Dust and trash removal systems 11 are provided between carding segments 10. Connections 12, which are diagrammatically illustrated, are provided on the dust and trash removal systems for suction devices (not shown). Each of the carding segments is connected to the mounting means 9 via fastening screws 14 loaded with a spring 13. Support means 15 for supporting carding segments 10 on mounting means 9 are provided at the ends of the dust and trash removal systems. The support means 15 which are formed as screws can be secured in a specific position via counter nuts 16. For the sake of clarity, only one respective carding segment 10, dust and trash removal system 11, connection 12, spring 13, fastening screw 14 and support means 15 with counter nuts 16 are shown.
As becomes apparent from FIG. 2, the cylinder is provided with a surface 17 suited for carding fibers, and the carding segments with a corresponding surface 18; as becomes also apparent from FIG. 2, each of the carding segments 10 carries a mote knife 19. The adjacent carding segment 10 is provided with a hold-down means 20. An air supply duct 21 is positioned between the hold-down means 20 and the carding segment 10 assigned thereto.
The air supply duct is substantially shaped in the manner of a gap with a square cross-section and extends substantially over the whole width of cylinder 2. However, an air supply duct 21 which tapers towards cylinder 2 is also possible.
An air-supply regulating means 22 for regulating the cross-section of the air supply duct 21 and thus the air flow passing through the air supply duct 21 is positioned at the end of the air supply duct 21 which faces away from cylinder 2. The air-supply regulating means 22 extends substantially over the whole width of the cylinder and the air supply duct 21, respectively, and is designed as a two-dimensional structure and provided on the upper side of a carding element in contact therewith and is displaceable in the running direction in parallel with the surface of the carding element 10. Elongated holes 23 are provided for adjusting the air-supply regulating means 22. The air-supply regulating means 22 can be fixed in the customary manner relative to the carding segment 10 with a fastening element 24 which is designed as a screw. The front end of the air-supply regulating means 22 is designed as a tongue 25, with the front section 26 of said tongue projecting into the air supply duct 21.
The hold-down means consists of a fastening section 27 and a base section 28. A fastening surface 29 which forms the air supply duct 21 together with carding segment 10 is provided at the side of the hold-down means which faces carding segment 10. The hold-down means 20 is spaced apart via a spacer 30 from the carding segment 10; a spacing of 10 mm has turned out to be optimum. To secure the hold-down means 20 onto carding segment 10, there are elongated holes 31, as well as fastening elements 32 which are designed as screws. To be able to adapt the air supply duct 21 to different airflow conditions, the distance between the fastening surface 29 and the carding segment 10 can be adjusted to lie between 5 mm and 30 mm. A base surface 33 which faces cylinder 2 is provided on its base section 28. The spacing of the base surface 33 relative to the surface of cylinder 2 can be adjusted to lie between 0.25 mm and 25 mm. An end 37 which extends substantially in a direction perpendicular to the surface of the cylinder is provided on its end section 36 which faces mote knife 19. As becomes apparent from FIG. 7, base section 28 may have a curvature 35. As becomes apparent from FIG. 2, the air supply duct 21 comprises an opening 34 which is formed from the fastening surface of the hold-down means 20 and carding segment 10. The opening 34 is positioned near surface 17.
A cover 38 is provided on the carding segment 10 carrying the mote knife 19 at the upper side thereof. The cover is adjustable relative to the upper side of the carding segment 10 in the running direction of cylinder 2. To this end, elongated holes 39 are provided on cover 38, cover 38 being adapted to be fixed in the customary manner with the aid of fastening elements 40 designed as screws relative to the associated carding segment 10.
Both the hold-down means and the mote knife 19 and cover 38 extend substantially over the whole width of cylinder 2, thereby defining a suction channel 41. Suction channel 41 terminates in connections 12, as can be seen in FIG. 1.
As becomes apparent from FIG. 2, the mote knife is designed as a substantially plate-shaped structure and is provided with a contact side 42 for contact with a carding segment 10 and a front side 43. Contact side 42 and front side 43 are substantially in parallel with each other and form the fastening section 44 of the mote knife. A blade section 45 with a blade 46 is provided at the end of the mote knife 19 that faces cylinder 2. As becomes apparent from FIGS. 3, 4, 5 and 6, blade 46 is provided with a section 47 of rounded cross-section. Moreover, the blade consists of a front side 48 and a back side 49 which pass each tangentially into the rounded section 47. The radius of the rounded section 47 is within a range of from 1 to 5 mm, preferably between 2 and 4 mm. In the embodiments of FIGS. 4, 5, and 6, an angle of about 70° is enclosed between the front side 48 and the back side 49. In the embodiment of FIG. 3, the radius of the rounded section approximately corresponds to the thickness of the mote knife 19. In the embodiment shown in FIG. 4, the mote knife 19 is considerably smaller in the area of the blade section 45 than in the fastening section 44. As becomes apparent from FIGS. 4, 5 and 6, the front side 48 is inclined with respect to the planar extension of the mote knife 19 by about 10° relative to the middle plane of the mote knife 19. Furthermore, the back side 49 is inclined by about 15° relative to a vertical plane in a direction perpendicular to the planar extension of the mote knife 19. In the embodiment of FIG. 5, a recess 50 is created due to the geometry of mote knife 19. In the embodiment of FIG. 4, the front side 48 of the blade extends in parallel with the front side 43. A step 51 is created thereby. In the embodiment shown in FIG. 6, a section 52 which is inclined in the opposite direction and which forms a recess 53 together with the front side 48 follows the inclined front side 48. FIG. 6 shows three recesses 52 which are arranged one after the other in waved configuration.
Blade 46 of the mote knife 19 is oriented in a direction opposite to the running direction of cylinder 2. The distance between blade 46 and the surface of cylinder 2 can be adjusted. To this end, the mote knife 19 has provided thereon elongated holes 54 which are shown in broken line and through which the fastening elements 55, which are designed as screws, project for fixing the mote knife 19 in the conventional manner relative to the associated carding segment 10.
The operation of the invention shall now be explained in more detail in the following:
During operation of the carding machine 1, the fiber material 5 which is fed via feed rollers 3 and 4 is carded between cylinder 2 and carding segments 10. Dirt, trash and short fibers as well as fiber fragments and synthetic fibers are removed on blade 46 of the mote knife 19 and carried away via suction channel 41 and connections 12. It has been found that it is possible to remove dust, trash and short fibers or the like in a considerably improved manner when the blade is provided with a rounded section 47. Another improvement of the discharging properties of dust, trash and short fibers and the like can be achieved when an air current is introduced through the air supply duct 21. To be able to make an adaptation to the respective fiber materials 5, both the mote knife 19, the hold-down means 20 and the air-supply regulating means 22 can be adjusted, as described above. The discharging properties can be optimized due to the adjustability of these components.
It has been found during operation of the dust and trash removal system that the solution of the invention leads to a considerable increase in the amount of dust, trash and short fibers as well as fiber fragments and to a considerable decrease in the proportion of good fibres relative to the absolute amount removed. | The present invention relates to a dust and trash removal system for carding machines or cards including a cylinder and fixedly mounted carding segments cooperating therewith. The system comprises a mote knife having a blade section whose blade is arranged in a direction opposite to the running direction of the cylinder at a small distance from the surface of the cylinder, as well as a hold-down element arranged in the running direction of the cylinder upstream of the mote knife with a base surface that extends substantially in parallel with the surface of the cylinder. To improve the discharging characteristics for dirt particles, short fibers, or the like, the blade, when being viewed in cross-section, has at least one rounded section with a radius greater than 1 mm. | 3 |
BACKGROUND OF THE INVENTION
The present invention relates to a group of polymers known as polyamidoamines which may be either linear or branched chain polymers. some of these polymers, which are initiated with ammonia, or a primary or secondary amine, are disclosed in a copending, commonly owned, application of another inventor, D. A. Tomalia, et al, under the title, "Dense Star Polymers", Ser. No. 565,686, filed Dec. 27, 1983, now U.S. Pat. No. 4,558,120, which is a continuation-in-part of an earlier application, Ser. No. 456,226, filed Jan. 7, 1983, now U.S. Pat. No. 4,507,466.
The compounds of the present invention are derivatives of the above polyamidoamines in which at least some of the amine hydrogens have been substituted and preferably in which at least one substituent is a phosphonic acid or alkylenephosphonic acid group or a salt thereof.
SUMMARY OF THE INVENTION
Those polyamidoamine polymers which have been found useful as chelating and/or threshold agents have the structure: ##STR1## wherein Z is at least one of ##STR2## and wherein the acid groups can be in the form of alkali, alkaline earth or ammonium salts, R and R' are saturated hydrocarbon residues having from 1 to 6 and 1 to 4 carbon atoms, respectively, and m and n are 0 to 10 and wherein at least one Z is not hydrogen.
DETAILED DESCRIPTION OF THE INVENTION
The polymers which are precursors of the derivatives which are the subject of the present invention are made by first reacting ammonia or an amine with an excess of an α,β-ethylenically unsaturated carboxylic acid ester, e.g. methyl acrylate (MA), at room temperature in methanol solution with stirring and then completing the reaction by allowing the reaction mixture to stand for a sufficient period of time, after which the excess ester is removed. The product is the Michael's addition product of ammonia or the amine with one mole of ester added for each mole of hydrogen on the nitrogen nucleus of the ammonia or amine molecule. This product is then reacted in methanol with an excess of a polyamine, e.g. ethylenediamine (EDA), at room temperature for a sufficient period of time to react one mole of diamine for each ester group in the Michael's addition product. The resulting product for the reaction between the Michael's addition product and the diamine wherein NH 3 , MA and EDA are employed has the following structure: ##STR3##
To make the products of the present invention, at least one of the amine hydrogens must be substituted with one of the previously identified groups (designated as Z) other than hydrogen.
The initiating polyamines which may be used in place of ammonia are the ethylene or propylene series of polyamines. Thus, ethylenediamine (EDA), diethylenetriamine (DETA), triethylenetetramine (TETA), propylene diamine (PDA), dipropylenetriamine (DPTE) and the like can be employed. The α,Ω-diamines, as well as the vicinal diamines enumerated above, can be employed as the initiating polyamine to make the precursor compounds of the compositions of the present invention. For example, 1,3-diaminopropane, 1,4-diaminobutane and the like α,Ω-diamines can be used. The initiating compound is reacted by the addition of the amine to an unsaturated ester such as methyl acrylate (MA).
The same amines employed as initiating compounds are also employed as the capping compound to form the amido linkage by reacting with the ester functionality.
An example of the structure of the EDA (PDA) initiated polymer reacted with MA and capped with EDA (PDA) is: ##STR4## wherein R is hydrogen or a methyl group.
The α,Ω-diamines would form similar structures. It should be recognized that, while the capping amine can be the same as the initiating one, it is not necessarily so. Thus, DETA or TETA can initiate a polymer capped with the simpler polyamine, EDA. Ammonia is not used for capping although it is a good initiating compound.
It should be recognized that the terminal amine nitrogens can be further reacted with an unsaturated ester and, in turn, with another amine to make a larger and more complex molecule as suggested by the formula shown in the Summary of the Invention section. These larger polymer molecules may be linear or branched. Molecular weight of the polyamidoamine precursors of the chelating and/or inhibiting agents of this disclosure were determined by gel permeation chromatography.
The preferred compounds are those which have all or most of the amine hydrogens substituted with an alkyl phosphonic acid group or a salt thereof.
Examples of the preparation and use of the products of the invention are shown following:
EXAMPLE 1
Deionized water (20 g) and 37.1 g of a 61% aqueous solution of an ethylenediamine initiated linear polyamidoamine (mol. wt. ˜7300) were weighed into a 500 ml round-bottom reaction flask equipped with a water-cooled reflux condenser, mechanical stirrer, thermometer with a temperature controller, and an addition funnel. Approximately 100 g of concentrated HCl solution and 39.5 g of phosphorous acid were added to the aqueous amine solution and the reaction mixture heated to reflux and maintained for one hour. Aqueous 37% formaldehyde solution (34.1 g) was added from the addition funnel over a one-hour period. The reaction mixture was heated at reflux for an additional four hours and then cooled. The product was the completely phosphonomethylated derivative of the linear polyamidoamine.
EXAMPLE 2
The procedure of Example 1 was followed except 43.1 g of 60% aqueous solution of an ethylenediame-initiated polyamidoamine (mol. wt. ˜7300) that had been reacted with 10 mole % 3-chloro-2-hydroxypropyltrimethylammonium chloride was used. This made a product in which 10% of the amine hydrogens had been replaced with 2-hydroxy-3(trimethyl ammonium chloride) propyl group. This partially quaternized amine was then phosphonomethylated by reacting the remainder of the amine nitrogens with phosphorous acid (37.8 g), 32.4 g of 37% formaldehyde solution, and 100 g of concentrated hydrochloric acid.
EXAMPLE 3
The procedure of Example 1 was followed, but using 37.0 g of 64% aqueous solution of an ethylenediamine-initiated polyamidoamine (mol. wt. ˜4600) that had been modified with 10 mole % of hydroxyethyl functionality by reaction with ethylene oxide. The remaining amine nitrogens were phosphomomethylated by reacting with 37.8 g of phosphorous acid, 32.4 g of 37% formaldehyde solution, and 100 g of concentrated hydrochloric acid.
EXAMPLE 4
The procedure of Example 1 was used to react an ethylenediamine-initiated polyamidoamine having the structure ##STR5## with 7 mole equivalents of H 3 PO 3 and CH 2 O in the presence of HCl. The product was a partially phosphonomethylated polyamidoamine, the remaining amine nitrogens being unsubstituted.
EXAMPLE 5
The procedure of Example 1 was used to react a diethylenetriamine-initiated polyamidoamine with 7 mole equivalents of H 3 PO 3 and CH 2 O in the presence of HCl. The product has a structure essentially that of Example 4 except for the initiating amine (DETA). The product was partially phosphonomethylated as in Example 4.
EXAMPLE 6
The procedure of Example 1 was used to react an ammonia-initiated and EDA capped polyamidoamine with 6 mole equivalents of H 3 PO 3 and CH 2 O in the presence of HCl. This gave a partially (66%) phosphonomethylated product.
EXAMPLE 7
The ammonia initiated amine of Example 6 was phosphonomethylated using 9 mole equivalents of H 3 PO 3 and CH 2 O in the presence of HCl. This product was completely phosphonomethylated.
EXAMPLE 8
The ammonia-initiated amine of Example 6 was carboxymethylated using 6 mole equivalents of glycolonitrile in the presence of excess caustic. The product was a partially (˜66%) carboxylated amidoamine.
EXAMPLE 9
The procedure of Example 1 was used to react an ammonia-initiated polyamidoamine (approximate molecular weight of 1400) with 21 mole equivalents of CH 2 O and H 3 PO 3 in the presence of HCl. The product was partially phosphonomethylated.
EXAMPLE 10
The polyamidoamine of Example 9 was reacted with 6 mole equivalents of CH 2 O and H 3 PO 3 in the presence of HCl and then carboxymethylated with 6 mole equivalents of glycolonitrile in the presence of excess caustic. The amine hydrogens were partially replaced with equal amounts of carboxymethyl and methylene phosphonic acid groups, but leaving somewhat more than 55% hydrogens.
CALCIUM SCALE INHIBITOR TEST
The compounds were evaluated as scale inhibitors for calcium sulfate scale according to the National Association of Corrosion Engineers test method TM-03-74. The results are shown in Table I and compared to a commercially available scale inhibition compound, aminotri(methylenephosphonic acid).
TABLE I______________________________________Scale Inhibition Data % of Ca.sup.++ Remaining Concentration* in SolutionCompound (ppm) 24 Hrs 48 Hrs 72 Hrs______________________________________Blank (none) 10 70 66 66Example 1 10 100 99 99Example 2 10 100 98 93Example 3 10 99 98 97Example 4 10 96 89 83Example 5 10 100 99 99Example 6 10 94 86 77Example 7 10 99 98 97Example 8 10 72 71 69Example 9 10 96 91 86Example 10 10 73 69 66Aminotri(methylene- 10 82 80 77phosphonic acid)______________________________________ *ppm based on active acid content
The compounds of this invention can also function as sequestering/chelating agents. Thus, certain of the above compounds were titrated with standard copper solution in the presence of chrome azurol-S indicator.
The compound of Example 8 complexed ˜2 moles of copper per mole of ligand. The compound of Example 7 complexed 5 moles of copper per mole of ligand.
It should be noted that while Examples 8 and 10 in Table I were not good threshold agents, they are satisfactory as chelating or sequestering agents. | New derivatives of polyamidoamines which contain at least one phosphonic, alkylphosphonic, hydroxyalkyl, carboxyalkly, alkylsulfonic or salts of the acid groups as substituents on a nitrogen are useful as chelating and/or threshold agents for preventing precipitation of metal ions. The preferred agents contain phosphonic acid groups or their salts. | 2 |
BACKGROUND OF THE INVENTION
This invention relates to friction materials, and more particularly to friction materials of the kind used for brake pads, brake linings, clutch facings and similar uses.
Friction materials of this kind are generally composed of a thermoset binder, an inorganic fibrous reinforcement and various fillers and other additives. These compositions are required to withstand severe operating temperatures and pressures under repeated application without failure or deterioration in friction properties and the fibrous reinforcement generally used is asbestos. Numerous proposals have been made of compositions containing other inorganic fibrous reinforcement but such materials have so far had limited commercial acceptance.
DETAILED DESCRIPTION OF THE INVENTION
According to the present invention a friction material comprises a thermoset binder, a fibrous reinforcement, and other fillers and additives, the thermoset binder comprising a phenol-formaldehyde resin and making up 20 to 45 percent by volume of the material, the fibrous reinforcement consisting solely of short lengths of steel fibre in an amount between 5 and 15 percent by volume, and at least 10 percent by volume of the material comprising an inert mineral filler. By "inert mineral filler" in this specification we mean a particulate filler whose presence does not substantially affect the friction properties of the material and which is an inexpensive mineral such as barytes, whiting or silica. We exclude metal oxides from this class of fillers since they are used for other purposes in friction materials.
The inert mineral filler will generally be present in an amount between 10 and 35 percent by volume, and is most important from a cost point of view when comparing these materials with asbestos-based conventional materials, since asbestos is a cheap raw material being replaced by relatively expensive man-made fibre. Hence it is necessary to find a friction material having satisfactory properties but able to carry a loading of cheap filler material.
The fibrous reinforcement preferably consists of fine steel fibres having a length of the order of 1 to 5 mm and a diameter of the order of 0.125 mm. The steel may be a mild steel. The fibrous reinforcement preferably constitutes at least 9% by volume of the friction material.
The thermoset binder includes a thermoset resin based on a phenol-formaldehyde material but may also include a heat and chemical resistant vulcanized rubber, such as a nitrile rubber. Preferably a mixture of such materials is used in which the phenol-formaldehyde resin material is preferably the major constituent i.e. more than 50% of said mixture. When a rubber is used it may be incorporated into the friction material in the form of a solution in an organic solvent such as trichloroethylene, or in the form of a powder, and a vulcanizing agent such as sulphur can be also used.
It is usual in the manufacture of friction materials to include various other material as friction and wear modifiers the proportions of which can be varied to adjust to the friction and other properties of the materials.
Examples of friction and wear modifiers are carbon, graphite, antimony trisulphide and molybdenum disulphide and metals in a finely divided form. Examples of suitable metals are copper, brass and tin. A mixture of such materials may be used, and the total amount of such materials may be up to 40 percent by volume.
The friction materials of the present invention are particularly suited to be manufactured by a pressmoulding technique in which all the ingredients of the material are compounded together, the compounded mix disintegrated and (optionally) dried and then moulded into a component such as a brake pad in a die under pressure. The moulded component is then removed from the die and baked to cure the binder.
The invention provides friction materials which contain no asbestos and yet which have friction properties comparible to conventional asbestos-reinforced materials.
EXAMPLES OF THE INVENTION
The invention will now be illustrated by way of example only, by means of the following example.
EXAMPLE 1
Sample disc brake pads were made using the formulation given below in Table I. The ingredients were compounded together the nitrile rubber being introduced as a powder and the resulting dry mix was disintegrated and press-moulded in a die into the shape of discbrake pads. The mouldings so produced were baked in an oven to cure the binder.
TABLE I______________________________________Nitrile rubber 12.07 parts by volumeSulphur 3.18Phenol-Formaldehyde Resin 29.82Steel Fibres 10.00Carbon Black 5.71Silica 6.44Barytes 12.42Graphite 8.97Antimony trisulphide 2.53Molybdenium disulphide 1.90Copper (Powdered) 5.70Tin (Powdered) 1.26______________________________________
The sample disc-brake pads were tested and their friction properties found to be comparable to materials containing asbestos as the fibre reinforcement.
EXAMPLE 2
This example illustrates a formulation with a higher loading of steel fibres.
Disc brake pads were manufactured to the formulation given below in Table II by the same method as used in Example 1 except that the nitrile rubber in the present example was introduced as a 16% (by weight) solution in trichloroethylene.
TABLE II______________________________________Nitrile rubber 12.07 volumes(introduced in solution)Sulphur 3.18 volumes(introduced in solution)Phenol-formaldehyde resin 29.82 volumes(introduced in solution)Steel fibres 15.00 volumes(introduced in solution)Zircon 1.00 volumes(introduced in solution)Barytes 20.96 volumes(introduced in solution)Graphite 8.97 volumes(introduced in solution)Antimony trisulphide 2.00 volumes(introduced in solution)Molybdenum disulphide 1.00 volumes(introduced in solution)Copper (powdered) 4.50 volumes(introduced in solution)Tin (powdered) 1.50 volumes(introduced in solution)______________________________________
In tests, on a dynamometer, of the pads produced the coefficient of friction varied from 0.32 (cold) to 0.44 (hot) and wear was less than that of many conventional asbestos reinforced materials at this level of friction. The assembly shear strength of two pads was measured, the values obtained being 1410 and 1360 psi. ##EQU1##
EXAMPLE 3
This example illustrates the use of a lower binder content and higher loading of inert filler (Barytes). Disc brake pads were made by the same method as Example 2 to the formulation given in Table III.
TABLE III______________________________________Nitrile rubber 8.04 volumes(introduced in solution)Sulphur 3.18 volumes(introduced in solution)Phenol-formaldehyde resin 19.88 volumes(introduced in solution)Steel fibre 10.00 volumes(introduced in solution)Carbon black 13.97 volumes(introduced in solution)Zircon 1.00 volumes(introduced in solution)Sillimanite 2.50 volumes(introduced in solution)Barytes 25.96 volumes(introduced in solution)Graphite 8.97 volumes(introduced in solution)Antimony trisulphide 2.00 volumes(introduced in solution)Copper (powdered) 4.50 volumes(introduced in solution)______________________________________
The wear of these pads was similar to those of Example 2 and coefficient of friction varied from 0.27 (cold) to 0.48 (hot). The assembly shear strengths measured were 2210 and 1890 psi.
EXAMPLE 4
This example illustrates the use of an even lower binder content at the same loading of barytes. Disc brake pads were made as in Example 2 to the formulation given in Table IV.
TABLE IV______________________________________Nitrile rubber 6.03 volumes(introduced in solution)Sulphur 3.18 volumes(introduced in solution)Phenol-formaldehyde resin 14.91 volumes(introduced in solution)Steel fibre 10.00 volumes(introduced in solution)Zircon 1.00 Volumes(introduced in solution)Sillimanite 2.50 volumes(introduced in solution)Barytes 25.96 volumes(introduced in solution)Graphite 8.97 volumes(introduced in solutionLead sulphide 6.99 volumes(introduced in solution)Coke (powdered) 13.96 volumes(introduced in solutionAntimony trisulphide 2.00 volumes(introduced in solution)Copper (powdered 4.50 volumes(introduced in solution)______________________________________
The wear of these pads was slightly higher than that of Examples 2 and 3 and the coefficient of friction varied from 0.30 (cold) to 0.40 (hot). The assembly shear strengths measured were 1360 and 1150 psi. | Asbestos-free friction material compositions containing from about 20 to 45% by volume of the material of a thermoset binder of a phenol formaldehyde resin and optionally a heat and chemical reistant rubber, up to 10% by volume of an inert mineral filler and as the sole fibrous reinforcement 5 to 15% by volume of short lengths of steel fibers are disclosed. The compositions are useful as brake pads and the like and has properties comparable with asbestos-based materials. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
Not applicable.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not applicable.
REFERENCE TO SEQUENCE LISTING, A TABLE OR A COMPUTER PROGRAM LISTING COMPACT DISC APPENDIX
Not applicable.
BACKGROUND OF THE INVENTION
The invention is in the field of seating design and construction.
BRIEF SUMMARY OF THE INVENTION
The invention comprises a seating assembly of first and second seating components releasably secured together without the need for tools, by at least one strap latch. The strap latch comprises a strap with one end of the strap affixed to the first component and the other end of the strap affixed to a latch. The latch of the strap latch releasably engages a catch which is affixed to the second component.
Preferably, three or more components are releasably joined without the need for tools by using a combination of one or more component interlocking features and at least one strap latch. Also in a preferred embodiment, adjacent seating units can be ganged together using a strap latch.
The seating assembly may also feature a seat support with fixed forward and rear frame members, and a floating rear frame member attached to the fixed rear frame member with at least one strap, with the seating web attached along its front edge to the fixed forward frame member and along its back edge to the floating rear frame member. This seat support appears to be horizontal when unoccupied, but the seat webbing and strap have sufficient stretch such that when a downward force is applied to the seat, the floating rear frame member is depressed, such that the seat has a rearward incline. This allows for a seat that appears flat, but feels inclined to the occupant.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front perspective view of a chair with a tablet arm, completely assembled, but without cushions, while ganged to a second upholstered chair;
FIG. 2 is a detailed top perspective view of a latch with the strap attached.
FIG. 2A is a detailed view of a latch and a catch in the ready position, showing alignment of the strap;
FIGS. 3A-3C are detail views of the latch in its various positions as it is pivoted over center into its locked position in the catch, with the strap not shown, for purposes of clarity;
FIG. 4 is a perspective view of the base, configured to receive a chair and a tablet arm;
FIG. 5 is a perspective view of a tablet arm;
FIG. 6 is a top perspective view of the interior of the tablet arm, and the H-shaped brace and strap latch;
FIG. 7 is a side perspective view of the base with the tablet arm installed thereon;
FIG. 8 is a top perspective view of the base and the tablet arm, with the strap latch in the ready position;
FIG. 9 is a top perspective view of the base and the tablet arm, with the strap latch in the latched position;
FIG. 10 is a top view of the seat;
FIG. 11 is a bottom perspective view of the seat;
FIG. 12 is a top perspective view of the base, the tablet arm and the seat;
FIG. 13 is a detailed side view of the side rail of the seat and its interaction with the base of the chair;
FIG. 14 is a slightly elevated side perspective view of the base, tablet arm and seat support, as it looks when the chair is un-occupied;
FIG. 15 is a slightly elevated side perspective view of the base, tablet arm and seat support, as it looks when the chair is occupied;
FIG. 16 is a bottom perspective view of the back;
FIG. 17 is a top perspective view of the chair with the back lined up for attachment to the base and the seat;
FIG. 18 is a bottom perspective view of the base, the seat and the back, showing the strap latch and order of stacking and interlocking of the elements;
FIG. 19 is a cross sectional view of a chair; and
FIG. 20 is a bottom perspective view, showing the ganging of a first chair to a second chair.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows a ganged seating assembly 30 of two preferred embodiment chair assemblies 32 and 32 ′, one of which ( 32 ) is shown un-upholstered and with an optional tablet arm 130 , and the other of which ( 32 ′) is shown upholstered. Each chair assembly 32 includes a base 90 ( FIG. 4 ), an interlocking seat 140 , a back 160 , and an optional tablet arm 130 ( FIG. 1 ). In the preferred embodiment, these components are modularly connected in an interlocking manner, without the need for tools and are secured together by one or more strap latches 50 ( FIGS. 2-3 ). Strap latches 50 are also used to attach, or “gang” one chair assembly 32 to an adjacent chair assembly 32 ′ to form a seating assembly 30 which is capable of being configured in a custom manner ( FIG. 1 ).
Strap latch 50 comprises a strap 52 secured to one chair assembly 32 component, with a latch 54 at one end of the strap 50 , which engages a catch 70 mounted on another chair assembly 32 component ( FIGS. 2-3 ). The strap 50 has one end affixed to a component of the chair assembly 32 and the other end rotatably attached to the latch 54 , e.g., by passing the end of the strap 50 through a slot 56 in the latch 54 and wrapping the strap 50 around the intermediate portion 57 of the latch 54 located between the catch engaging projections 58 on the leading edge of the latch 54 and fastening the end of the strap 50 to the trailing portion of strap 50 ( FIG. 2 ). The leading edge of latch 54 is defined by two spaced catch engaging projections 58 , each comprising a flat catch engaging edge 60 to engage the catch 70 , and tabs 62 outside of and projecting beyond the flat catch engaging edge 60 to prevent side to side motion of the latch 54 once it is in place on the catch 70 . The trailing edge 69 of latch 54 opposite the two catch engaging leading edge portions 60 serves as a handle which can be used to fasten the strap latch 50 to catch 70 .
The catch 70 , in one preferred embodiment, comprises a back plate 72 with two projecting sides 74 , each projecting side 74 having a flat catch or fulcrum protrusion 76 and a rounded stop protrusion 78 . The fulcrum protrusion 76 is characterized by an overhanging flat edge 80 positioned such that the flat edge 80 has an angle of at least about ninety degrees (90°), and preferably an oblique angle of greater than about ninety degrees (90°), from the direction that the strap 50 will approach from, and an angled edge 82 which angles back toward the back plate 72 . The rounded stop 78 is located farther from the direction of approach of the strap 52 than the flat fulcrum protrusion 76 and does not extend as far from the back plate 72 as the fulcrum protrusion 76 . The rounded stops 78 serve as a stop for the latch 54 as it is moved from the ready position to the locked position, and prevent the latch 54 from rotating any further than just slightly over center relative to fulcrum 76 when the latch 54 is held in engagement with protrusion 76 by the tension placed on latch 54 by strap 52 .
To operate the strap latch 50 , the latch 54 is placed perpendicularly to the catch 70 , with the flat catch engaging edges 60 of the latch 54 against the catch 70 between the fulcrum protrusions 76 and the rounded stop protrusions 78 . ( FIG. 2 ) Then the latch 54 is rotated toward the round stop protrusions 78 such that the flat catch engaging edges 60 are in contact with the fulcrum protrusions 76 , and the latch 54 is cammed over center relative to fulcrum protrusions 76 ( FIGS. 3A , 3 B, 3 C). The length of strap 52 is such that in this position, the latch 54 is applying a stretching force on strap 52 , which pulls the catch engaging edges 60 of latch 54 against the fulcrum protrusions 76 and the trailing edge 69 of latch 54 toward the rounded stop protrusions 78 , thereby locking latch 54 against catch 70 until someone applies a counter rotating force to rotate latch 54 back the other way.
In one example of a preferred embodiment, the base 90 is configured to accommodate a seat 140 , back 160 and a tablet arm 130 . ( FIG. 4 ) Base 90 includes a chair accommodating portion 92 and a tablet arm accommodating portion 94 . Base 90 has three horizontally oriented base members 96 extending from the front to the back of the base 90 , one at the outside edge of the chair accommodating portion 92 , one dividing the chair accommodating portion 92 and the tablet arm accommodating portion 94 , and one at the outside edge of the tablet arm accommodating portion 94 . The horizontal base member 96 dividing the chair accommodating portion 92 and the tablet arm accommodating portion 94 may be wider than the other horizontal base members 96 , to accommodate the width of the tablet arm 130 and the seat support 140 , with the additional width extending into the chair accommodating portion of the base 92 . Each horizontal base member 96 may optionally be fitted with a foot 98 near its front edge and back edge so that the base 90 is lifted off of the ground. (If the seating assembly 32 was not intended to include an arm, the base may utilize only two horizontal base members 96 , as the horizontal base member to support the outer edge of the tablet arm 130 would be unnecessary.)
To define the chair accommodating portion 92 and the tablet arm accommodating portion 94 , and to provide a basis for the installation of these items, a base frame 100 is provided on top of the horizontal base members 96 . The base frame 100 includes three members 102 ( 102 , 102 ′, 102 ″) extending from front-to-back (one over each horizontal base member 96 ) and two base frame members 104 ( 104 , 104 ′) extending side-to-side across the chair assembly 32 , one at the back, and one at the front. At intervals along the length of the base frame members 102 , 104 , downwardly extending fingers 106 may be provided, which extend through corresponding holes 108 in the horizontal base member 96 to form mortise and tenon joints between the horizontal base members 96 and the base frame members 102 , 104 . The base frame members 102 , 104 each have complimentary slots 110 cut approximately halfway through their depth so that, where they intersect, the members 102 , 104 interlock to form a cross lap joint. A catch 70 is secured to frame member 102 ″ for receiving the latch 54 of a strap latch 50 secured to tablet arm 130 . Another catch 70 is secured to back frame member 104 ′, in the center of the chair supporting portion of base 90 . This facilitates securing back 160 in place. Additional base frame members 102 , 104 could be provided. For example, additional side-to-side base frame members 104 could be provided between the front and rear base frame members 104 to add stability to the base frame 100 .
The horizontal base members 96 may also be provided with interior corner tabs 112 , extending inwardly to the chair accommodating portion 92 and the tablet accommodating portion 94 of the base frame 100 at each interior corner. Downwardly-extending tab engaging members 114 may then be provided on the base frame members 102 , 104 , to engage the tabs 112 and further stabilize the base frame 100 on the horizontal base members 96 .
In the chair accommodating portion 92 , the top edge of the side-to-side base frame members 104 have notches 116 therein at each of the four corners where the seat 140 will be attached, with the edge 118 between the notches 116 being raised. The bottom edge of the forward side-to-side base frame member 104 may also be provided with one or more seat receiving slots 120 , for example, two slots 120 , one at each side of the chair accommodating portion 92 .
A tablet arm 130 , with a flat area on top which can be covered to create a writing surface may be included in the chair assembly 32 . ( FIGS. 5 , 6 ) The bottom of the tablet arm 130 is configured to fit over the outside of the tablet arm receiving portion 94 of base 90 , with the tablet arm 130 having slots 132 along the bottom interior edge, corresponding with the side-to-side base frame members 104 so that the bottom of the tablet arm 130 rests on the horizontal base members 96 , with the side-to-side base frame members 104 passing through the slots 132 . The bottom of the tablet arm 130 may also include one or more interlocking projections 134 which extend perpendicularly from the tablet arm 130 , adjacent to one or more of the side-to-side base frame members 104 . The sides of the tablet arm 130 may be enclosed with solid walls 136 , if desired.
The interior side of the wall 136 of the tablet arm 130 may be provided with an H-shaped brace comprising a horizontal platform 138 , and two vertically extending legs 139 . The brace may also be an upside down U-shaped brace with a horizontal platform 138 and two downwardly extending vertical legs 139 . When arm 130 is assembled to base 90 , legs 139 rest on top of the front-to-back base frame member 102 ″ thereby supporting the horizontal platform 138 . ( FIGS. 6 , 8 )
The tablet arm 130 is installed by placing the tablet arm 130 over the tablet arm accommodating portion 94 of the base 90 , so that the base frame members 104 and 104 ′ are positioned within the corresponding slots 132 on the tablet arm 130 . The interlocking projection 134 extends along the side-to-side base frame member 104 , and the brace 138 , 139 is positioned directly on top of the front-to-back base frame member 102 ″. Then, the latch 54 of a strap latch 50 , comprising a strap 52 which is securely fastened to brace top platform 138 at one end, and having a latch 54 attached to the free end, is engaged into fixed catch 70 on frame member 102 ″. This secures the tablet arm 130 to the base 90 . The catch 70 is securely attached to the middle front-to-back base frame member 102 ″ directly below the H-shaped brace 138 , 139 facing in toward the center of the tablet arm 130 . The strap 52 may be attached to the top of the brace 138 using any method known in the art, and the catch 70 may be fastened to the base frame member 102 using any method known in the art, including staples, nails, screws, bolts, adhesives, tape, or any other known method of fastening. The latch 54 is placed in the ready position adjacent to the catch 70 , as described above, and is then rotated into the locked position, such that the strap 52 is pulled taut, holding the tablet arm 130 securely to the base 90 ( FIGS. 8 , 9 ).
A seat 140 , preferably having a fixed forward frame member 142 , a fixed rear frame member 144 , side rails 146 , a floating rear frame member 148 , seat webbing 150 and preferably at least two straps 152 affixing the floating frame member 148 to the fixed rear frame member 144 . ( FIGS. 10 , 11 ) The fixed forward frame member 142 has at least one rearwardly projecting tab 154 , which corresponds with the seat support receiving slot 120 in the forward side-to-side base frame member 104 . The side rails 146 are attached to the fixed forward frame member 142 and are configured to rest on top of the base frame 100 . At the rear of the seat support 140 , the side rails 146 each have a pair of upwardly extending tapered members 156 , defining a slot 158 therebetween for the fixed rear frame member 144 to be inserted. The side rails 146 may also be provided with a notch 160 on the bottom edge, which may be generally in line with the tapered members 156 , to correspond with the rear side-to-side base frame member 104 ′ and assist to hold the seat support 140 in place over the base 90 . The seat webbing 150 is fixedly attached to the fixed forward frame member 142 and the floating rear frame member 148 , using any method known in the art for such attachment, including staples, nails, screws, adhesives, tapes, or any other known or equivalent method.
To install the seat 140 , it is placed over the chair accommodating portion of the base 92 by inserting the rearwardly projecting tabs 154 into the seat support receiving slots 120 on the forward side-to-side base frame member 104 , sliding seat 140 rearwardly, and then lowering the back portion of the seat support 140 , so that the notch 160 rests on the top edge of the rear side-to-side base frame member 104 , preventing movement of the seat support 140 in the front-to-back direction and the side rails 146 rest in notches 116 on top of the base frame members 104 . ( FIGS. 12 , 13 ) When placed in position, the raised edges 118 engage with the interior of the side rails 146 , thereby preventing lateral movement of the seat support 140 once it is placed in position. Side rail 146 of seat 140 is also then positioned over interlocking projection 134 of tablet arm 130 , such that tablet arm 130 is additionally secured to base 90 by this interlocking relationship with seat 140 .
As described above, when the seat webbing 150 is attached along its back edge to the floating rear frame member 148 , when no downward force is applied to the seat of the chair assembly 32 , the floating rear frame member 148 is generally in the same plane as the fixed forward and rear frame members 142 , 144 , such that the seat of the chair assembly 32 appears to be generally horizontal. ( FIG. 14 ) However, the seat webbing 150 and the straps 152 have sufficient stretch, such that when a downward force is applied to the seat of the chair assembly 32 the floating rear frame member 148 is permitted to move downward, such that the chair assembly 32 , when occupied has a rearwardly inclined seat which is more comfortable for the occupant than a horizontal seat. ( FIG. 15 )
After seat 140 is installed on the base 90 , a back 160 may be installed. The back 160 comprises a pair of tapered side members 162 , a bottom cross member 164 , cross braces 166 , and back webbing 168 . ( FIGS. 16-17 , 19 ) The tapered side members 162 are spaced to fit around the outside of the seat side rails 146 , and extend upward the height of back 160 . The front edge of the tapered side members 162 may also be shaped to provide ergonomic support, such as by having a curved lumbar support region 170 . The bottom cross member 164 , extends across the rear bottom edge of the tapered side members 162 . The cross braces 166 extend between the tapered side members 162 , and are spaced and oriented so as to correspond to the upwardly extending tapered members 156 of the side rails 146 , so that one cross brace 166 is on top of and in front of the upwardly extending tapered members 156 and the other cross brace 166 is on top of and behind the upwardly extending tapered members 156 . A connecting brace 172 may also be placed between the cross braces 166 , with a slit through the middle of the connecting brace 172 to permit attachment of the strap 52 on one of the cross braces 166 , and then allow the strap 52 to go downward to interact with a catch 70 through the slit in the connecting brace 172 .
To install, back 160 is placed into position over the seat 140 , such that the cross braces 166 align with the corresponding upwardly extending tapered members 156 . ( FIG. 17 ) Back 160 is lowered, such that the cross braces 166 are adjacent to the upwardly extending tapered members 156 , in the front and back thereof, limiting any front-to-back movement of the seat back 160 , and due to the angle of the cross braces 166 , also limiting the downward movement of the seat back 160 . The bottom cross member 164 rests outside the rear of the base frame 100 , preventing forward motion or backward rotation of the seat back 160 .
A strap latch 50 extends downwardly from back cross brace 166 , or optionally from the connecting brace 172 , between the floating rear frame member 148 and the fixed rear frame member 144 , to interact with a catch 70 placed on the interior wall of the rear side-to-side base frame member 104 ′. The strap latch 50 is fastened as described above to secure the seat back 160 to the base frame member 104 ′, sandwiching the seat 140 between the base frame member 104 ′ and back 160 . ( FIG. 18 )
Preferably before the components of the chair assembly 32 are thus assembled, chair assembly 32 can be quickly and easily upholstered to provide a cushioned chair assembly 32 ′. ( FIG. 19 ) An upholstered envelope 201 incorporating a back cushion 202 is slipped over back 160 and secured using hook and loop fasteners or the like. Similarly, an upholstery envelope 205 including a seat cushion 206 is slipped over seat 140 to finish it. Finally, an upholstery envelope is slipped over tablet arm 130 . The upholstered components are then assembled without tools, as described above.
When the upholstery on the chair needs to be replaced, the components can be similarly separated for ease of removal of the old worn upholstery, and replaced with new upholstery envelopes, as discussed above. The newly upholstered components can then be reassembled in the manner discussed above.
Chairs 32 can be ganged together using a strap latch 50 . To facilitate this, an additional strap latch 50 is provided on the interior side of the base frame member 102 of a first chair 32 that would be adjacent to a second chair 32 ′ to form a grouped seating arrangement 30 . ( FIG. 20 ) The strap 52 is positioned to wrap underneath the horizontal base frame member 96 of the first chair assembly 32 , under the horizontal base frame member 96 of the second chair assembly 32 ′, and then up to a catch 70 provided on the interior of the base frame member of the second chair assembly 32 ′. A catch 70 may also be provided on the first chair assembly 32 where the strap 52 is fastened. The strap 52 and latch 54 can then be rolled up and secured to the catch 70 for storage when the first chair assembly 32 is not ganged to a second chair assembly 32 ′.
The chair and seating arrangements described herein may contain different components, for example, the tablet arm could be replaced by a regular arm, an arm with a different functionality, or be left off entirely; the seat could be replaced by a double- or triple-wide seat; the seat back could be configured in various manners or left off, and other configurations for each individual component are possible, and multiple components can be joined to form various seating arrangements.
Additionally, especially with reference to the system of notches, slots, tabs and other features to interlock the frames, it is understood that various arrangements of interlocking components may be provided that are within the scope of this invention, and descriptions of particular shapes or interactions between the components should not be considered limiting. Of course it is understood that the above is a description of the preferred embodiments, and that various changes and alterations can be made without departing from the spirit and broader aspects of the invention. | A seating assembly with a base, a seat and a back which have interlocking features, and a strap latch removeably securing the back to the base with a portion of the seat sandwiched therebetween. The strap latch comprises a strap affixed to one component, with a latch attached to its free end, and a catch member affixed to another component. The seat may also be configured to appear horizontal but to have a rearward incline when occupied, by affixing the seat webbing to a fixed forward member and a floating rear member, and attaching the floating member to a fixed rear member via straps, wherein the straps and the seat webbing have sufficient elasticity to allow the floating member to be depressed when a downward force is applied to the seat. | 0 |
BACKGROUND OF THE INVENTION
[0001] The present invention describes a process for conditioning organic pigments in microreactors.
[0002] Organic pigments are well known and widely used for pigmenting macro-molecular organic materials such as paints, plastics or printing inks. Assynthesized, they are usually either very fine prepigments or coarse crude pigments, which do not meet industrial requirements. Finely divided prepigments frequently have to be subjected to a thermal treatment to obtain the required properties. Coarsely divided crude pigments are frequently subjected to comminution, which usually has to be followed by thermal treatment in order that pigments meeting the industrial requirements may be obtained.
[0003] The thermal treatment may produce various desired effects, for example narrow the particle size distribution; shift the average particle size to higher values; deagglomerate as-ground comminuted and strongly agglomerated pigments; add auxiliaries and distribute them homogeneously over the pigment surface; and effect a change between various crystal forms in some cases. These effects then lead to the desired industrial requirements, for example the desired hue, increased color strength or cleanness of hue, improved dispersibility, rheology, lightfastness, gloss or weatherfastness, or control over light scattering properties and hence over the hiding power.
[0004] Literature discloses thermal treatment processes for a wide variety of organic pigments:
[0005] DE-A-12 61 106 discloses a batch process for thermal treatment of substituted quinacridone pigments by heating the crude pigments in solvents under pressure.
[0006] EP-A-0 318 022 discloses a batch process for producing a hiding dimethyl-perylimide pigment where the hiding power is provided by thermal treatment.
[0007] EP-A-0 672 729 discloses a batch process for producing a hiding diketopyrrolo-pyrrole pigment where the hiding power is provided by thermal treatment.
[0008] EP-A-0 655 485 and EP-A-0 799 863 disclose batch processes for producing quinacridone pigments where the transformation from the alpha-phase to the beta-phase is effected by thermal treatment with an organic solvent and in the presence of aqueous alkali.
[0009] Batch processes are known for producing an azo pigment where a thermal treatment is carried out in an aqueous medium (EP-A-0 077 025) or in organic solvents
[0010] (EP-A-0 894 831).
[0011] A feature common to these batch processes is the need to control the process parameters. For example, temperature and duration of the thermal treatment, suspension concentration, use of solvents or presence of acids or bases are decisive for the color properties of the pigments obtained and their quality constancy. Moreover, the scaleup of new products from the laboratory scale to the large industrial scale is inconvenient with batch processes and can present problems, since for example vessel and stirrer geometries or heat transfers have a substantial effect on particle size, particle size distribution and color properties.
[0012] It is an object of the present invention to provide an environmentally friendly, economical and technically reliable process for preparing organic pigments by thermal treatment that provides very constant adherence to the desired process parameters and simplifies scaleup.
[0013] It is known to carry out certain chemical reactions in microreactors. Micro-reactors are constructed from stacks of grooved plates and are described in DE 39 26 466 C2 and U.S. Pat. No. 5,534,328. It is pointed out in U.S. Pat. No. 5,811,062 that microchannel reactors are preferably used for reactions that do not require or produce materials or solids that would clog the microchannels.
SUMMARY OF THE INVENTION
[0014] It has now been found, that, surprisingly, microreactors are useful for conditioning organic pigments by thermal treatment of their prepigment suspensions.
[0015] As used herein, the term “microreactor” is representative of miniaturized, preferably continuous, reactors which are known under the terms of microreactor, minireactor, micromixer or minimixer and which differ by reason of the dimensions and construction of the channel structures. It is possible to use, for example, microreactors as known from the cited references or from publications of the Institut fucr Mikrotechnik Mainz GmbH, Germany, or of the Fraunhofer Institut für Chemische Technologie, Pfinztal, or else commercially available microreactors, for example Selecto™ (based on Cytos™) from Cellular Process Chemistry GmbH, Frankfurt/Main.
[0016] The invention accordingly provides a process for conditioning organic pigments, which comprises thermally treating a liquid prepigment suspension in a microreactor.
[0017] Advantageously, the prepigment suspension is fed to the microreactor continuously. The conventional sequence of adding prepigment suspension, water, organic solvents, acids and/or bases can be realized; similarly, the auxiliaries used in conventional processes may likewise be used in the process of the invention.
[0018] Useful organic pigments include, for example perylene, perinone, quinacridone, quinacridonequinone, anthraquinone, anthanthrone, benzimidazolone, disazo condensation, azo, indanthrone, phthalocyanine, triarylcarbonium, dioxazine, aminoanthraquinone, diketopyrrolopyrrole, thioindigo, thiazineindigo, isoindoline, isoindolinone, pyranthrone or isoviolanthrone pigments or mixtures thereof.
DESCRIPTION OF THE DRAWINGS
[0019] [0019]FIG. 1 is an exploded view of a microreactor useful for the preparation of organic pigments by thermal treatment, according to the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0020] Preferred organic pigments for the purposes of the present invention include for example C.I. Pigment Red 123 (C.I. No. 71 145), C.I. Pigment Red 149 (C.I. No. 71 137), C.I. Pigment Red 178 (C.I. No. 71 155), C.I. Pigment Red 179 (C.I. No. 71 130), C.I. Pigment Red 190 (C.I. 71 140), C.I. Pigment Red 224 (C.I. No. 71 127), C.I. Pigment Violet 29 (C.I. No. 71 129), C.I. Pigment Orange 43 (C.I. No. 71 105), C.I. Pigment Red 194 (C.I. No. 71 100), C.I. Pigment Violet 19 (C.I. No. 73 900), C.I. Pigment Red 122 (C.I. No. 73 915), C.I. Pigment Red 192, C.I. Pigment Red 202 (C.I. No. 73 907), C.I. Pigment Red 207, C.I. Pigment Red 209 (C.I. No. 73 905), C.I. Pigment Red 206 (C.I. No. 73 900/73 920), C.I. Pigment Orange 48 (C.I. No. 73 900/73 920), C.I. Pigment Orange 49 (C.I. No. 73 900/73 920), C.I. Pigment Orange 42, C.I. Pigment Yellow 147, C.I. Pigment Red 168 (C.I. No. 59 300), C.I. Pigment Yellow 120 (C.I. No. 11 783), C.I. Pigment Yellow 151 (C.I. No. 13 980), C.I. Pigment Brown 25 (C.I. No. 12 510), C.I. Pigment Violet 32 (C.I. No. 12 517), C.I. Pigment Orange 64; C.I. Pigment Brown 23 (C.I. No. 20 060), C.I. Pigment Red 166 (C.I. No. 20 730), C.I. Pigment Red 170 (C.I. No. 12 475), C.I. Pigment Orange 38 (C.I. No. 12 367), C.I. Pigment Red 188 (C.I. No. 12 467), C.I. Pigment Red 187 (C.I. No. 12 486), C.I. Pigment Orange 34 (C.I. No. 21 115), C.I. Pigment Orange 13 (C.I. No. 21 110), C.I. Pigment Red 9 (C.I. No. 12 460), C.I. Pigment Red 2 (C.I. No. 12 310), C.I. Pigment Red 112 (C.I. No. 12 370), C.I. Pigment Red 7 (C.I. No. 12 420), C.I. Pigment Red 210 (C.I. No. 12 477), C.I. Pigment Red 12 (C.I. No. 12 385), C.I. Pigment Blue 60 (C.I. No. 69 800), C.I. Pigment Green 7 (C.I. No. 74 260), C.I. Pigment Green 36 (C.I. No. 74 265); C.I. Pigment Blue 15:1,15:2, 15:3,15:4,15:6 and 15 (C.I. No. 74 160); C.I. Pigment Blue 56 (C.I. No. 42 800), C.I. Pigment Blue 61 (C.I. No. 42 765:1), C.I. Pigment Violet 23 (C.I. No. 51 319), C.I. Pigment Violet 37 (C.I. No. 51 345), C.I. Pigment Red 177 (C.I. No. 65 300), C.I. Pigment Red 254 (C.I. No. 56 110), C.I. Pigment Red 255 (C.I. No. 56 1050), C.I. Pigment Red 264, C.I. Pigment Red 270, C.I. Pigment Red 272 (C.I. No. 56 1150), C.I. Pigment Red 71, C.I. Pigment Orange 73, C.I. Pigment Red 88 (C.I. No. 73 312), C.I. Pigment Yellow 175 (C.I. No. 11 784), C.I. Pigment Yellow 154 (C.I. No. 11 781), C.I. Pigment Yellow 83 (C.I. No. 21 108), C.I. Pigment Yellow 180 (C.I. No. 21 290), C.I. Pigment Yellow 181 (C.I. No. 11 777), C.I. Pigment Yellow 74 (C.I. No. 11 741), C.I. Pigment Yellow 213, C.I. Pigment Orange 36 (C.I. No. 11 780), C.I. Pigment Orange 62 (C.I. No. 11 775), C.I. Pigment Orange 72, C.I. Pigment Red 48:2/3/4 (C.I. No. 15 865:2/3/4), C.I. Pigment Red 53:1 (C.I. No. 15 585:1), C.I. Pigment Red 208 (C.I. No. 12 514), C.I. Pigment Red 185 (C.I. No. 12 516), C.I. Pigment Red 247 (C.I. No. 15 915).
[0021] It is also possible to use more than one organic pigment or solid solutions of organic pigments or combinations of organic with inorganic pigments.
[0022] The liquid phase of the prepigment suspension can consist of water, organic solvents, acids, bases or of a mixture of individual or all of these substances.
[0023] Useful organic solvents include for example alcohols of 1 to 10 carbon atoms, such as methanol, ethanol, n-propanol, isopropanol, n-butanol, sec-butanol, tert-butanol, n-pentanol, 2-methyl-2-butanol, 2-methyl-2-pentanol, 3-methyl-3-pentanol, 2-methyl-2-hexanol, 3-ethyl-3-pentanol, 2,4,4-trimethyl-2-pentanol, cyclohexanol; or glycols, such as ethylene glycol, diethylene glycol or glycerol; ethers, such as tetrahydrofuran, dimethoxyethane or dioxane; glycol ethers, such as monomethyl or monoethyl ethers of ethylene glycol or propylene glycol, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, butylglycol or methoxybutanol; ketones, such as acetone, diethyl ketone, methyl isobutyl ketone, methyl ethyl ketone or cyclohexanone; aliphatic amides, such as formamide, dimethylformamide or N,N-dimethylacetamide; urea derivatives, such as tetramethylurea; or cyclic carboxamides, such as N-methylpyrrolidone, valerolactam or caprolactam; C 1 -C 4 -alkyl carboxylates, such as butyl formate, ethyl acetate or propyl propionate; or C 1 -C 4 -glycol esters of carboxylic acids; or C 1 -C 4 -alkyl phthalates or benzoates, such as ethyl benzoate; nitriles, such as acetonitrile or benzonitrile; aliphatic or aromatic hydrocarbons, such as cyclohexane or benzene; or alkyl-, alkoxy-, nitro- or halogen-substituted benzene, such as toluene, xylenes, ethylbenzene, anisole, nitrobenzene, chlorobenzene, o-dichlorobenzene, 1,2,4-trichlorobenzene or bromobenzene; or other substituted aromatics, such as benzoic acid or phenol; aromatic heterocycles, such as pyridine, morpholine, picoline or quinoline; and also dimethyl sulfoxide and sulfolane. The solvents mentioned may also be used as mixtures.
[0024] Preferred organic solvents are alcohols of 1 to 6 carbon atoms, especially ethanol, propanols, butanols, pentanols; aliphatic carboxamides, especially dimethylformamide or N,N-dimethylacetamide; cyclic carboxamides, especially N-methylpyrrolidone; aromatic hydrocarbons, especially toluene, xylenes or ethylbenzene; chlorinated aromatic hydrocarbons, especially chlorobenzene, o-dichlorobenzene; and dimethyl sulfoxide.
[0025] It is advantageous to use 3 to 40, preferably 4 to 20, especially 5 to 15, parts by weight of the liquid medium (water, solvent, acid, base) of the prepigment suspension per 1 part by weight of prepigment.
[0026] Useful acids include for example inorganic acids, for example hydrochloric acid, phosphoric acid and preferably sulfuric acid; or aliphatic and aromatic carboxylic or sulfonic acids, such as formic acid, acetic acid, propionic acid, butyric acid, hexanoic acid, oxalic acid, benzoic acid, phenylacetic acid, benzenesulfonic acid or p-toluenesulfonic acid, preferably acetic acid and formic acid; or mixtures of acids.
[0027] Useful bases includes, for example, inorganic bases such as, for example, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate and calcium hydroxide, preferably sodium hydroxide; or mixtures of bases; or bases such as, for example, trimethylamine, triethylamine or ammonia; or salts of organic acids such as, for example, sodium acetate or sodium formate.
[0028] The conditioning according to the invention may be preceding, accompanied or followed by the addition to the (pre)pigment suspension of one or more auxiliaries selected from the group consisting of pigment dispersants, surfactants, fillers, standardizers, resins, defoamers, dustproofers, extenders, shading colorants, preservatives, drying retarders and rheology control additives.
[0029] Useful pigment dispersants include the literature-known derivatives of organic pigments which contain imidazole, pyrazole, phthalimide, sulfonamide, aminomethylene, cyclic carboxamide or saccharin groups or sulfonic acid or carboxylic acid groups or salts thereof.
[0030] Useful surfactants include anionic, cationic or nonionic substances or mixtures thereof.
[0031] Useful anionic substances include for example fatty acid taurides, fatty acid N-methyltaurides, fatty acid isethionates, alkylphenylsulfonates, alkylnaphthalene-sulfonates, alkylphenol polyglycol ether sulfates, fatty alcohol polyglycol ether sulfates, fatty acid amidepolyglycol ether sulfates, alkyl sulfosuccinamates, alkenylsuccinic monoesters, fatty alcohol polyglycol ether sulfosuccinates, alkane-sulfonates, fatty acid glutamates, alkyl sulfosuccinates, fatty acid sarcosides; fatty acids, for example palmitic, stearic and oleic acid; soaps, for example alkali metal salts of fatty resins, naphthenic acids and resin acids, for example abietic acid, alkali-soluble resins, for example rosin-modified maleate resins and condensation products based on cyanuric chloride, taurine, N,N′-diethylamino-propylamine and p-phenylenediamine. Particular preference is given to resin soaps, i.e. alkali metal salts of resin acids.
[0032] Useful cationic substances include for example quaternary ammonium salts, fatty amine alkoxylates, alkoxylated polyamines, fatty amine polyglycol ethers, fatty amines, di- and polyamines derived from fatty amines and fatty alcohols and alkoxylates derived from these di- and polyamines, imidazolines derived from fatty acids and salts of these cationic substances.
[0033] Useful nonionic substances include for example amine oxides, fatty alcohol polyglycol ethers, fatty acid polyglycol esters, betaines, such as fatty acid amide N-propylbetaines, phosphoric esters of fatty alcohols or fatty alcohol polyglycol ethers, fatty acid amide ethoxylates, fatty alcohol-alkylene oxide adducts and alkylphenol polyglycol ethers.
[0034] The total amount of auxiliaries added may be in the range from 0 to 40% by weight, preferably from 0.5 to 20% by weight, particularly preferably from 1 to 15% by weight, based on (pre)pigment.
[0035] In what follows, prepigment, water, solvent, acid, base and auxiliary are collectively referred to as feedstocks.
[0036] To carry out the conditioning according to the invention, the feedstocks are introduced into a microreactor individually or as mixtures. In principle all conceivable combinations of the feedstocks are possible, provided the streams are industrially handleable.
[0037] The preparation of mixtures of feedstocks to form streams may also be carried out in advance in micromixers or upstream mixing zones. It is also possible for feedstocks to be metered into downstream mixing zones or into downstream micromixers or -reactors.
[0038] The thermal treatment is carried out at pressures between atmospheric pressure and 100 bar, preferably between atmospheric pressure and 25 bar. The temperature can vary within wide limits, preferably between 20 and 300° C., especially between 50 and 250° C., in particular between 60 and 200° C.
[0039] The thermal treatment according to the invention can also take place immediately following a microreactor synthesis of an organic pigment, in a downstream reactor.
[0040] The pigment suspensions prepared by the process of the invention are worked up according to known processes to isolate the pigment. Solvents may be recycled.
[0041] A microreactor is constructed from a plurality of laminae which are stacked and bonded together and whose surfaces bear micromechanically created structures which interact to form spaces for chemical reactions. The system contains at least one continuous channel connected to the inlet and the outlet.
[0042] The flow rates of the streams are limited by the apparatus, for example by the pressures which result depending on the geometry of the microreactor. It is desirable for the thermal treatment to take place completely in the microreactor, but it is also possible to adjoin a delay zone to create a delay time that may be required.
[0043] The flow rates are advantageously between 0.05 ml/min and 5 l/min, preferably between 0.05 ml/min and 500 ml/min, particularly preferably between 0.05 ml/min and 250 ml/min, especially between 0.1 ml/min and 100 ml/min.
[0044] A microreactor useful for the preparation of organic pigments by thermal treatment is described in FIG. 1 by way of example. The present microreaction system is in this case constructed from six microstructured metal laminae, stacked and bonded together, plus a lid plate (DP) and a base plate (BP) to form a processing module that is firmly held bonded together to compress sealing sheets between the plates.
[0045] The present microreaction system includes two heat exchangers for cooling and/or heating medium, a mixing zone for any necessary mixing of the feedstocks and a short delay zone. The heat exchanger (W 1 ) preheats the streams flowing separately into the plate (E). The streams or feedstocks are then mixed within plates (M), which form a conjoint space. The delay zone (R) brings the prepigment suspension to the desired reaction temperature with the aid of the heat exchanger (W 2 ), so that the thermal treatment can take place.
[0046] A microreaction system is preferably operated continuously, and the quantities of materials present in the microreactor are in the microliter (μl) to milliliter (ml) range.
[0047] The dimensions of the microstructured regions within the reactor are decisive for the thermal treatment of organic pigments. These dimensions have to be sufficiently large that, in particular, solid particles can pass through without problem and so not clog up the channels. The smallest clear width of the microstructures should be about ten times larger than the diameter of the largest particles. Furthermore, it has to be ensured, by appropriate geometric styling, that there are no dead water zones, for example dead ends or sharp corners, where for example particles could sediment. Preference is therefore given to continuous paths having round corners. The structures have to be sufficiently small to exploit the intrinsic advantages of microreaction technology, namely excellent heat control, laminar flow, diffuse mixing and low internal volume.
[0048] The clear width of the suspension-ducting channels is advantageously 5 to 10 000 μm, preferably 5 to 3 000 μm, particularly preferably 10 to 800 μm, especially 20 to 700 μm.
[0049] The clear width of the heat exchanger channels depends primarily on the clear width of the suspension-ducting channels and is advantageously not more than 10 000 μm, preferably not more than 3 000 μm, especially not more than 800 μm. The lower limit of the clear width of the heat exchanger channels is uncritical and is at most constrained by the pressure increase of the heat exchanger fluid to be pumped and by the necessity for optimum heat supply or removal.
[0050] The dimensions of a preferred microreaction system depicted in FIG. 1 by way of example are:
Heat exchanger structures: channel width ˜600 μm channel height ˜250 μm Mixer: channel width ˜600 μm channel height ˜500 μm
[0051] In the microreactor type described by way of example, the six superposed and closely conjoined metal laminae are preferably supplied with all heat exchanger fluids and feedstocks from above. The pigment suspension and the heat exchanger fluids are preferably removed upwardly. The possible supply of further feedstocks (e.g. water, solvent, acids or bases) involved in the thermal treatment may also be realized via a T-junction located directly upstream or downstream of the reactor. The requisite concentrations and flows are preferably controlled via precision piston pumps and a computer-controlled control system. The temperature is monitored by integrated sensors and controlled with the aid of the control system and of a thermostat/cryostat.
[0052] The system depicted here is made of stainless steel; other materials, for example glass, ceramic, silicon, plastics or other metals, may also be used. It is surprising and was unforeseeable that the conditioning of organic pigments by thermal treatment is possible in this technically simple and reliable manner, since it was hitherto assumed that the production of a solid material in the microreactor would lead to the system being clogged up.
[0053] Organic pigments prepared according to the invention are useful for pigmenting macromolecular natural or synthetic organic materials, for example cellulose ethers and esters, such as ethylcellulose, nitrocellulose, cellulose acetate, cellulose butyrate, natural resins or synthetic resins, such as addition polymerization resins or condensation resins, for example amino resins, especially urea- and melamine-formaldehyde resins, alkyd resins, acrylic resins, phenolic resins, polycarbonates, polyolefins, such as polystyrene, polyvinyl chloride, polyethylene, polypropylene, polyacrylonitrile, polyacrylic esters, polyamides, polyurethanes or polyesters, gum, casein, silicone and silicon resins, individually or mixed.
[0054] It is immaterial in this connection whether the macromolecular organic compounds mentioned are present as plastically deformable masses, melts or in the form of spinning solutions, paints, coatings or printing inks. Depending on the intended use, it is comparatively advantageous to use the pigments obtained according to the invention as blends or in the form of preparations or dispersions. Based on the macromolecular organic material to be pigmented, the pigments prepared according to the invention are used in an amount of preferably 0.05 to 30% by weight, preferably 0.1 to 15% by weight.
[0055] The pigments prepared according to the process of the invention can be used to pigment the industrially common baking finishes from the class of the alkyd-melamine resin coatings, acrylic-melamine resin coatings, polyester coatings, high solids acrylic resin coatings, aqueous coatings based on polyurethane and also two-component coatings based on polyisocyanate-crosslinkable acrylic resins and especially automotive metallic coatings.
[0056] The pigments conditioned according to the invention are also useful as colorants in electrophotographic toners and developers, for example one- or two-component powder toners (also known as one- or two-component developers), magnetic toners, liquid toners, polymerization toners and also specialty toners. Typical toner binders are addition polymerization, polyaddition and polycondensation resins, such as styrene, styrene-acrylate, styrene-butadiene, acrylate, polyester, phenol-epoxide resins, polysulfones, polyurethanes, individually or in combination, and also polyethylene and polypropylene, which may each include further ingredients, such as charge control agents, waxes or flow assistants, or as subsequently modified with these additives.
[0057] The pigments conditioned according to the invention are further useful as colorants in powders and powder coatings, especially in triboelectrically or electrokinetically sprayable powder coatings used for surface coating of objects composed for example of metal, wood, plastic, glass, ceramic, concrete, textile material, paper or rubber.
[0058] Powder coating resins used are typically epoxy resins, carboxyl- and hydroxyl-containing polyester resins, polyurethane and acrylic resins together with customary hardeners. Combinations of resins are also used. For instance, epoxy resins are frequently used in combination with carboxyl- and hydroxyl-containing polyester resins. Typical hardener components (depending on the resin system) include for example acid anhydrides, imidazoles and also dicyandiamide and derivatives thereof, capped isocyanates, bisacylurethanes, phenolic and melamine resins, triglycidyl isocyanurates, oxazolines and dicarboxylic acids.
[0059] The pigments conditioned according to the invention are also useful as colorants in inkjet inks having an aqueous or a nonaqueous basis and also in inkjet inks which operate according to the hot-melt process.
[0060] The pigments conditioned according to the invention are also useful as colorants for color filters and also for additive as well as subtractive color generation.
EXAMPLES
[0061] To evaluate the coating properties of the pigments conditioned according to the invention, a selection was made, from among the multiplicity of known varnishes, of an alkyd-melamine (AM) resin varnish containing aromatic components and based on a medium-oil alkyd resin and on a butanol-etherified melamine resin, a high-solids acrylic resin baking varnish based on a nonaqueous dispersion (HS) and an aqueous polyurethane-based aqueous varnish (PUR). The color strength and hue were determined in accordance with DIN 55986. Millbase rheology after dispersion was rated on the following five-point scale:
5 thin 4 fluid 3 thick 2 slightly set 1 set
[0062] Following dilution of the millbase to the final pigment concentration, the viscosity was assessed using a Rossmann viscospatula type 301 from Erichsen.
[0063] Gloss measurements were carried out on cast films at an angle of 20° in accordance with DIN 67530 (ASTMD 523) using a “multigloss” gloss meter from Byk-Mallinckrodt.
[0064] The crystal phase of the pigments was determined by X-ray spectroscopy. The X-ray spectra were recorded using Cu Kα radiation. The X-ray diffraction spectra are reported in digital form. The relative intensities were 51-100% for strong lines, 11-50% for medium lines and 2-10% for weak lines.
[0065] In the examples which follow, parts and percentages are by weight.
Example 1
[0066] 0.1 mol of dimethyl aminoterephthalate hydrochloride is diazotized with sodium nitrite at 0 to 10° C. The clarified diazonium salt solution is added dropwise at room temperature over 1 hour to an acetate-buffered suspension of 0.1 mol of N-acetoacetyl-6-methoxy-7-aminoquinoxaline-2,3-dione in the presence of surfactant, for example ®Lutensol AT 25. As soon as the coupling has ended, the batch is heated to 96° C. and filtered and the filter residue is washed salt-free. The moist press cake is dried at 80° C. to obtain C.I. Pigment Yellow 213 prepigment.
[0067] 150 parts of C.I. Pigment Yellow 213 prepigment are suspended in 1 850 parts of N-methylpyrrolidone and the suspension is pumped via a calibrated piston pump into the microreactor inlet at a flow rate of 6 ml/min. In the microreactor the suspension is heated to 180° C. The reaction suspension emerging from the reactor is filtered and the press cake is washed with N-methylpyrrolidone and dried under reduced pressure.
[0068] The prepigment is present in the alpha-phase, characterized particularly by strong lines at 2theta 3.2, 7.9 and 8.8; and by a medium broad line at 26.6. A crystal phase change takes place during the conditioning in the microreactor; the pigment isolated following the conditioning is in the beta-phase: the three lines characteristic for the alpha-phase are no longer there; instead there is a new strong line at 2theta 9.2; the line at 26.6 becomes the strongest line in the diagram.
[0069] The particle sizes of the prepigments are substantially less than 70 nm. The conditioned pigment has a particle size distribution with an average particle size diameter of 221 nm.
[0070] The prepigment has a reddish-yellow hue, while the conditioned pigment has a greenish-yellow hue.
Example 2
[0071] The pigment is prepared as in example 1, except that the conditioning takes place at 130° C. instead of at 180° C.
[0072] The pigment thus prepared is likewise in the beta-phase and also has the greenish-yellow hue, but is substantially more transparent and more intensive than the pigment prepared as per example 1. | Organic pigments are conditioned by introducing a liquid prepigment suspension into a miniaturized continuous reactor and thermally treating therein. | 1 |
This is a continuation-in-part of application Ser. No. 27,875, filed Apr. 6, 1979, now abandoned, which is a continuation of application Ser. No. 607,028, filed Aug. 22, 1975, now U.S. Pat. No. 4,161,845, granted July 24, 1979.
SUMMARY OF THE INVENTION
This invention relates to a prefabricated door assembly and will have specific application to a door which can be inverted during its installation, depending upon the desired direction of swing of the door panel.
In the door assembly of this invention there is a panel which is hinged for pivotal movement to one of a pair of jambs. Enclosing the panel at its upper and lower edges is a pair of combined header and threshold means. The two jambs and two header and threshold means define a frame into which the door panel is fitted. Hinge means pivotally connect the door panel to one of the door jambs. Each combined header and threshold means is adapted for mounting either upon a foundation or under an overhead support, depending upon the desired vertical orientation of the panel and location of the assembly hinge means.
To mount the door assembly within a wall opening, the assembly is first rotated or inverted, if necessary, to place the hinge means at one specific side of the door panel, depending upon the desired direction of opening movement of the door. The assembly is then set into the wall opening with one of the combined header and threshold means resting upon the foundation. In this manner, one prefabricated door assembly can be utilized as a right or left-hand opening door, depending upon the vertical orientation of the assembly when fitted into the wall opening.
Accordingly, it is an object of this invention to provide a prefabricated door assembly which may be inverted to accommodate either left or right-hand opening movement of the door panel of the assembly.
Another object of this invention is to provide an invertible prefabricated door assembly which is of economical construction.
Still another object of this invention is to provide an invertible prefabricated door assembly which may be mounted within a wall opening through the utilization of simple hand tools.
Still another object of this invention is to provide an invertible prefabricated door assembly which is mountable in a rapid and simple manner.
Still another object of this invention is to provide a door assembly having a two piece threshold with a removable shoulder part.
And still another object of this invention is to provide an invertible prefabricated door assembly having a two piece combined header-threshold.
Other objects of this invention will become apparent upon a reading of the invention's description.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of one embodiment of the door assembly fitted within a wall opening.
FIG. 2 is an isolated perspective view of the door assembly of FIG. 1.
FIG. 3 is a vertical cross sectional view of the door assembly taken along line 3--3 of FIG. 2.
FIG. 4 is a vertical cross sectional view of the door assembly taken along line 4--4 of FIG. 1.
FIG. 5 is a perspective view of the isolated door assembly with portions broken away for purposes of illustration as seen from its opposite side.
FIG. 6 is a vertical cross sectional view of another embodiment of the door assembly.
FIG. 7 is a fragmented perspective view of the two piece combined header and threshold used in the door assembly of FIG. 6.
FIG. 8 is a perspective view of the two piece combined header and threshold shown in separated form.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The preferred embodiments illustrated are not intended to be exhaustive or to limit the invention to the precise forms disclosed. They are chosen and described in order to best explain the principles of the invention and its application and practical use to thereby enable others skilled in the art to best utilize the invention.
Door assembly 10 of FIGS. 1-5 includes jambs 12 and 14, a combined header and threshold 16 and another combined header and threshold 18. Jambs 12 and 14 and header and thresholds 16 and 18 are connected together at their respective end portions to define a rectangular frame into which a door leaf or panel 20 is fitted. Hinges 22 secure door panel 20 to jamb 12, enabling the door to be pivoted between open and closed positions. Located an equal distance between header and thresholds 16 and 18 is a door handle 24 and associated latch. A striker plate is carried by jamb 14 for the purpose of engaging the door latch to secure door panel 20 in its closed position. If desired, a centered window 30 may be located in door panel 20.
Combined header and thresholds 16 and 18 are of like construction. Each header and threshold 16 and 18 includes a plate part 32 and an offset plate part 34 separated by a shoulder 36. Plate part 34 may be angled as shown in the drawings. Additionally, the outer surface of plate part 34 of each header and threshold 16 and 18 may be provided with longitudinally extending serrations 38. Each jamb 12 and 14 includes offset parts connected by a shoulder 40 which lies in the same plane as shoulder 36 of each header and threshold 16 and 18. Shoulders 36 and 40 are overlapped by the marginal edges of door panel 20 when the panel is in its closed position with its latch extending into the latch opening in the striker plate. Weatherstripping 42 is applied to shoulders 26 and 30. When contacted by door panel 20 in its closed position, weatherstripping 42 serves to seal the panel around jambs 12 and 14 and combined header and thresholds 16 and 18.
In FIG. 1 door assembly 10 is shown fitted into an opening within side wall 44 of a building structure. The opening 45 in side wall 44 is defined by a foundation 46, which may be concrete, wood or of earthen composition, side stanchions 48 and an interconnecting overhead support 50. Wall opening 45 is sized so as to receive door assembly 10 with slight clearance. Door assembly 10 is positioned, such as by inverting the door assembly if necessary, to locate hinges 22 at one selected assembly side so as to enable door panel 20 to have either a left or right-hand opening and closing swing as desired. Any inversion of door assembly 10 other than changing the orientation or location of hinges 22 and door handle 24 will not change the method by which the assembly is fitted and secured within opening 45 in side wall 44 due to the similarity in construction of header and thresholds 16 and 18. Once door assembly 10 is fitted into wall opening 45, screws or similar attachment means are turned through jambs 12 and 16 and combined header and thresholds 16 and 18 into underlying stanchions 48 and overhead supports 50 to secure the assembly to wall 44.
From the above description it can be appreciated how easily prefabricated door assembly 10 with its combined header and thresholds 16 and 18 can be mounted in a wall opening while giving the door user an option of having either a right or left-hand opening door, without changing or otherwise modifying the door assembly.
In FIG. 6 the door assembly of FIGS. 1-5 is shown with header and thresholds 16' and 18' of modified form. Each header and threshold 16' and 18' includes a base member 60 and a detachable attachment part 62. Attachment part 62 includes an end edge which when the part is connected to the base member forms shoulder 36 over which door panel 20 overlaps when closed. Base member 60 has a central groove 64 which divides the base member into two sections and into which lip 66 of attachment part 62 is interlockingly fitted. Additionally, base member 60 has an end edge groove 68 formed in one of its sections into which lip 70 of the attachment part is fitted to connect the base and attachment parts together. The outer surfaces 72,74 of the base member sections are substantially flush and grooved to provide a foot hold. Likewise, the outer surface 76 of the attachment part is grooved to provide a foot hold when the part is used as a threshold or a decor item when the part is used as a header.
Attachment part 62 can be connected to base member 60 by first inserting its outturned lip 66 into base member groove 64 and then pivoting the attachment part over section surface 74 of the base member until lip 70 of the attachment part snap fits into base member groove 68. Attachment part 62 may be detached from that base member 60 of the combined header and threshold being used in the installed assembly as the threshold to allow for the use of a flush or non-shouldered threshold.
It is to be understood that the invention is not to be limited to the details above given but may be modified within the scope of the appended claims. | A prefabricated door assembly which includes a panel, a pair of jambs and two combined header and thresholds. The jambs and combined header and thresholds form a rectangular frame into which is fitted the door panel. The panel is pivotally hinged to one of the jambs. Each combined header and threshold is adapted to be mounted either upon a foundation or under an overhead support, depending upon the vertical orientation of the panel and location of the door hinge. | 4 |
BACKGROUND OF THE INVENTION
[0001] The present invention relates to a process for the preparation of 2-substituted 4-hydroxy-4-methyltetrahydropyrans from the acid-catalyzed reaction of 3-methylbut-3-en-1-ol with an aldehyde, where a stable fragrance quality is attained without the odor impression of troublesome off-notes.
PRIOR ART
[0002] 2-Substituted 4-hydroxy-4-methyltetrahydropyrans are valuable compounds for use as aroma chemicals. Thus, for example, the cis/trans-diastereomer mixture of 2-(2-methylpropyl)-4-hydroxy-4-methyltetrahydropyran
[0000]
[0000] is characterized by a pleasant lily of the valley scent and is suitable to a particular degree for use as aroma chemical, e.g. for producing fragrance compositions.
[0003] EP 1 493 737 A1 discloses a process for the preparation of mixtures of ethylenically unsaturated 4-methyl- or 4-methylenepyrans and the corresponding 4-hydroxypyrans by reacting the corresponding aldehydes with isoprenol, where the reaction is initiated in a reaction system in which the molar ratio of aldehyde to isoprenol is greater than 1, i.e. the aldehyde is used in excess. Moreover, the document discloses the subsequent dehydration of said mixtures to the desired ethylenically unsaturated pyrans.
[0004] WO 2011/147919 describes a process for the preparation of 2-substituted 4-hydroxy-4-methyltetrahydropyranols and specifically of 2-isobutyl-4-hydroxy-4-methyltetrahydropyran by reacting isoprenol with prenal and subsequent hydrogenation.
[0005] WO 2010/133473 describes a process for the preparation of 2-substituted 4-hydroxy-4-methyltetrahydropyrans of the formula (A)
[0000]
[0000] where the radical R 1 is a straight-chain or branched alkyl or alkenyl radical having 1 to 12 carbon atoms, an optionally alkyl-substituted cycloalkyl radical having in total 3 to 12 carbon atoms or an optionally alkyl- and/or alkoxy-substituted aryl radical having in total 6 to 12 carbon atoms, in which isoprenol (3-methylbut-3-en-1-ol) is reacted with an aldehyde of the formula R 1 —CHO, where the reaction is carried out in the presence of water and in the presence of a strongly acidic cation exchanger.
[0006] WO 2011/154330 describes a process comparable to WO 2010/133473, where the resulting reaction mixture is subjected to a distillative processing in a dividing-wall column or in two thermally coupled distillation columns.
[0007] As is described in WO 2010/133473 and WO 2011/154330, during the acid-catalyzed reaction of isoprenol (3-methylbut-3-en-1-ol) with an aldehyde of the formula R 1 —CHO, a complex reaction mixture is formed which, besides 2-substituted 4-hydroxy-4-methyltetrahydropyrans, also comprises dehydrated by-products of the formulae (D), (E) and/or (F)
[0000]
[0000] and also, as further by-products, inter alia the 1,3-dioxanes (G)
[0000]
[0008] The unpublished international patent application PCT/EP2013/071409 describes a process for the preparation of 2-substituted 4-hydroxy-4-methyltetrahydropyrans of the general formula (A) and of 2-substituted 4-methyltetrahydropyrans of the general formula (B)
[0000]
[0000] in which
R 1 is straight-chain or branched C 1 -C 12 -alkyl, straight-chain or branched C 2 -C 12 -alkenyl, unsubstituted or C 1 -C 12 -alkyl- and/or C 1 -C 12 -alkoxy-substituted cycloalkyl having in total 3 to 20 carbon atoms or unsubstituted or C 1 -C 12 -alkyl- and/or C 1 -C 12 -alkoxy-substituted aryl having in total 6 to 20 carbon atoms,
in which
a) 3-methylbut-3-en-1-ol is reacted with an aldehyde of the formula R 1 —CHO, where R 1 in the formula has the meaning given above, in the presence of an acidic catalyst, where a reaction mixture is obtained which comprises at least one 2-substituted 4-hydroxy-4-methyltetrahydropyran of the general formula (A), at least one of the compounds (D), (E) or (F) and at least one dioxane compound (G)
[0000]
where R 1 has the meaning given above,
b) the reaction product from step a) is subjected to a separation to give a fraction enriched in 2-substituted 4-hydroxy-4-methyltetrahydropyrans of the general formula (A) and a fraction which comprises at least one of the compounds (D), (E) or (F) and at least one dioxane compound (G),
c) the fraction which comprises at least one of the compounds (D), (E) or (F) and at least one dioxane compound (G) is subjected to a hydrogenation,
d) from the hydrogenation product obtained in step c) a fraction enriched in 2-substituted 4-methyltetrahydropyrans (B) and a fraction enriched in at least one dioxane compound (G) are isolated.
[0015] Romanov et al. describe in the Journal of Applied Chem. of the USSR, 55(1), p. 140-143 (1982) (English translation from Zhurnal Prikladnoi Khimii, Vol. 55, No. 1, 157-161 (1981)) the acid-catalyzed reaction of the dioxane compound G′) to the dihydropyrans E′) and F′).
[0000]
[0016] The table mentions 4-methyl-2-isobutyl-5,6-dihydropyran and 4-methyl-2-isobutyl-3,6-dihydropyran. The acidic catalysts used are H 2 SO 4 or sulfonic acid group-containing styrene-divinylbenzene ion exchangers. The reaction takes place with dioxane compounds G′) in pure form and in the presence of cyclohexane or toluene as solvent.
[0017] Romanov et al. describe in the Journal of Applied Chem. of the USSR, 56 (1), p. 2526-2528 (1983) (English translation from Zhurnal Prikladnoi Khimii, Vol. 55, No. 12, 2778-2780 (1982)) the acid-catalyzed isomerization of 2-R-4,4-dimethyl- and 2-R-4-methyl-4-phenyl-1,3-dioxanes to 2-R-4,4-methyl- and 2-R-4-phenyl-1,3-tetrahydropyran-4-ols.
[0018] An essential requirement placed on the synthesis of aroma chemicals and specifically on odor substances is the consistently high quality of the product. An essential quality criterion is that a stable fragrance quality is attained without the odor impression of troublesome off-notes. In this connection, neither in the case of production in a batch process must individual batches have undesired odor notes, nor, in the case of continuous production must the fragrance quality deteriorate in the course of production. The latter can be attributed for example to aging processes of the catalyst used and changes in the product spectrum associated therewith. Specifically in the case of the preparation of 2-substituted 4-hydroxy-4-methyltetrahydropyrans from the acid-catalyzed reaction of 3-methylbut-3-en-1-ol with an aldehyde, it is sometimes observed that the fragrance quality, specifically of the formulated end product following prolonged storage no longer corresponds to the expectation. In these cases, the product often has an undesired cheesy odor note. The object of the present invention is to provide an improved process for the preparation of 2-substituted 4-hydroxy-4-methyltetrahydropyrans which reduces or avoids this problem.
[0019] Surprisingly, it has now been found that this object is achieved if the reaction product obtained during the acid-catalyzed reaction of 3-methylbut-3-en-1-ol with an aldehyde for the preparation of 2-substituted 4-hydroxy-4-methyltetrahydropyrans, prior to its distillative separation, is brought into contact with an acidic ion exchanger and/or admixed with a strong acid. This acid treatment can reliably avoid the formation of troublesome odor notes. This is particularly surprising since the preparation according to the invention of the 2-substituted 4-hydroxy-4-methyltetrahydropyrans already takes place in the presence of an acidic catalyst.
SUMMARY OF THE INVENTION
[0020] The invention provides a process for the preparation of 2-substituted 4-hydroxy-4-methyltetrahydropyrans of the general formula (I)
[0000]
[0000] in which
R 1 is straight-chain or branched C 1 -C 12 -alkyl, straight-chain or branched C 2 -C 12 -alkenyl, unsubstituted or C 1 -C 12 -alkyl- and/or C 1 -C 12 -alkoxy-substituted cycloalkyl having in total 3 to 20 carbon atoms or unsubstituted or C 1 -C 12 -alkyl- and/or C 1 -C 12 -alkoxy-substituted aryl having in total 6 to 20 carbon atoms,
in which
a) 3-methylbut-3-en-1-ol of the formula (IV)
[0000]
[0000] is reacted with an aldehyde of the formula (V)
[0000] R 1 —CHO (V)
[0000] in which
R 1 is straight-chain or branched C 1 -C 12 -alkyl, straight-chain or branched C 2 -C 12 -alkenyl, unsubstituted or C 1 -C 12 -alkyl- and/or C 1 -C 12 -alkoxy-substituted cycloalkyl having in total 3 to 20 carbon atoms or unsubstituted or C 1 -C 12 -alkyl- and/or C 1 -C 12 -alkoxy-substituted aryl having in total 6 to 20 carbon atoms,
in the presence of an acidic catalyst, where a reaction mixture is obtained which comprises at least one 2-substituted 4-hydroxy-4-methyltetrahydropyran of the general formula (I),
b) the reaction mixture from step a) is subjected to a distillative separation to give at least one fraction enriched in the 2-substituted 4-hydroxy-4-methyltetrahydropyrans of the general formula (I),
where the reaction mixture from step a), prior to use in step b) and/or during use in step b), is brought into contact with an acidic ion exchanger and/or admixed with a strong acid.
[0025] The invention further provides 2-substituted 4-hydroxy-4-methyltetrahydropyrans of the general formula (I) which are obtainable by the process defined above and below. This is in particular 2-isobutyl-4-hydroxy-4-methyltetrahydropyran.
[0026] The 2-substituted 4-hydroxy-4-methyltetrahydropyrans of the general formula (I) obtained by the process according to the invention, in particular 2-isobutyl-4-hydroxy-4-methyltetrahydropyran, are advantageously suitable for use as aroma chemical, specifically as fragrance.
DESCRIPTION OF THE INVENTION
[0027] Unless stated more precisely hereinbelow, the terms
[0000] “2-substituted 4-hydroxy-4-methyltetrahydropyran” and
“2-(2-methylpropyl)-4-hydroxy-4-methyltetrahydropyran”
in the context of the invention refer to cis/trans mixtures of any composition, and also to the pure conformational isomers. The aforementioned terms further refer to all enantiomers in pure form, as well as racemic and optionally active mixtures of the enantiomers of these compounds.
[0028] Wherever the discussion hereinbelow is of cis and trans diastereomers of the compounds (I), in each case only one of the enantiomeric forms is depicted. Merely for the purposes of illustration, the isomers of 2-(2-methylpropyl)-4-hydroxy-4-methyltetrahydropyran (I) are given below:
[0000]
[0029] In the context of the present invention, the expression straight-chain or branched alkyl preferably stands for C 1 -C 6 -alkyl and particularly preferably for C 1 -C 4 -alkyl. Alkyl is in particular methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl (2-methylpropyl), sec-butyl (1-methylpropyl), tert-butyl(1,1-dimethylethyl), n-pentyl or n-hexyl. Specifically, alkyl is methyl, ethyl, n-propyl, isopropyl, or isobutyl.
[0030] In the context of the present invention, the expression straight-chain or branched alkoxy preferably stands for C 1 -C 6 -alkoxy and particularly preferably for C 1 -C 4 -alkoxy.
[0031] Alkoxy is in particular methoxy, ethoxy, n-propyloxy, isopropyloxy, n-butyloxy, isobutyloxy, sec-butyloxy, tert-butyloxy, n-pentyloxy or n-hexyloxy. Specifically, alkoxy is methoxy, ethoxy, n-propyloxy, isopropyloxy, or isobutyloxy.
[0032] In the context of the present invention, the expression straight-chain or branched alkenyl preferably stands for C 2 -C 6 -alkenyl and particularly preferably for C 2 -C 4 -alkenyl Besides single bonds, the alkenyl radical also has one or more, preferably 1 to 3, particularly preferably 1 or 2 and very particularly preferably one, ethylenic double bond. Alkenyl is in particular ethenyl, 1-propenyl, 2-propenyl, 1-methylethenyl, 1-butenyl, 2-butenyl, 3-butenyl, 1-methyl-1-propenyl, 2-methyl-1-propenyl, 1-methyl-2-propenyl or 2-methyl-2-propenyl.
[0033] In the context of the invention, cycloalkyl refers to a cycloaliphatic radical having preferably 3 to 10, particularly preferably 5 to 8, carbon atoms. Examples of cycloalkyl groups are in particular cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl or cyclooctyl. Specifically, cycloalkyl is cyclohexyl.
[0034] Substituted cycloalkyl groups can have one or more (e.g. 1, 2, 3, 4 or 5) substituents depending on the ring size. These are preferably selected independently of one another from C 1 -C 6 -alkyl and C 1 -C 6 -alkoxy. In the case of a substitution, the cycloalkyl groups carry preferably one or more, for example one, two, three, four or five C 1 -C 6 -alkyl groups. Examples of substituted cycloalkyl groups are in particular 2- and 3-methylcyclopentyl, 2- and 3-ethylcyclopentyl, 2-, 3- and 4-methylcyclohexyl, 2-, 3- and 4-ethylcyclohexyl, 2-, 3- and 4-propylcyclohexyl, 2-, 3- and 4-isopropylcyclohexyl, 2-, 3- and 4-butylcyclohexyl and 2-, 3- and 4-isobutylcyclohexyl.
[0035] In the context of the present invention, the expression “aryl” comprises mono- or polynuclear aromatic hydrocarbon radicals having usually 6 to 18, preferably 6 to 14, or particularly preferably 6 to 10, carbon atoms. Examples of aryls are in particular phenyl, naphthyl, indenyl, fluorenyl, anthracenyl, phenanthrenyl, naphthacenyl, chrysenyl, pyrenyl, etc., and specifically phenyl or naphthyl.
[0036] Substituted aryls can have one or more (e.g. 1, 2, 3, 4 or 5) substituents depending on the number and size of their ring systems. These are preferably selected independently of one another from C 1 -C 6 -alkyl and C 1 -C 6 -alkoxy. Examples of substituted aryl radicals are 2-, 3- and 4-methylphenyl, 2,4-, 2,5-, 3,5- and 2,6-dimethylphenyl, 2,4,6-trimethyl-phenyl, 2-, 3- and 4-ethylphenyl, 2,4-, 2,5-, 3,5- and 2,6-diethylphenyl, 2,4,6-triethyl-phenyl, 2-, 3- and 4-propylphenyl, 2,4-, 2,5-, 3,5- and 2,6-dipropylphenyl, 2,4,6-tri-propylphenyl, 2-, 3- and 4-isopropylphenyl, 2,4-, 2,5-, 3,5- and 2,6-diisopropylphenyl, 2,4,6-triisopropylphenyl, 2-, 3- and 4-butylphenyl, 2,4-, 2,5-, 3,5- and 2,6-dibutylphenyl, 2,4,6-tributylphenyl, 2-, 3- and 4-isobutylphenyl, 2,4-, 2,5-, 3,5- and 2,6-diisobutyl-phenyl, 2,4,6-triisobutylphenyl, 2-, 3- and 4-sec-butylphenyl, 2,4-, 2,5-, 3,5- and 2,6-di-sec-butylphenyl, 2,4,6-tri-sec-butylphenyl, 2-, 3- and 4-tert-butylphenyl, 2,4-, 2,5-, 3,5- and 2,6-di-tert-butylphenyl and 2,4,6-tri-tert-butylphenyl.
[0037] Preferably, R 1 in the compounds of the formulae (I), (II), (III.1), (III.2), (III.3), (V), and (VI) is straight-chain or branched C 1 -C 12 -alkyl or straight-chain or branched C 2 -C 12 -alkenyl. Particularly preferably, R 1 is straight-chain or branched C 1 -C 6 -alkyl or straight-chain or branched C 2 -C 6 -alkenyl. In a further preferred embodiment, R 1 is phenyl.
[0038] Meanings for the radical R 1 that are preferred according to the invention are therefore, for example, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, n-pentyl, n-hexyl or n-heptyl, preferably methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, very particularly preferably isobutyl (2-methylpropyl).
[0039] Consequently, in the context of one preferred embodiment, the present invention relates to a process for the preparation and isolation of 2-(2-methylpropyl)-4-hydroxy-4-methyltetrahydropyran of the formula (Ia).
[0000]
Step a)
[0040] One of the starting materials for step a) of the process according to the invention is 3-methylbut-3-en-1-ol (isoprenol) of the formula (IV),
[0000]
[0041] Isoprenol is readily accessible by known processes from isobutene and formaldehyde on every scale and is commercially available. No particular requirements are placed on the purity, quality or preparation process of the isoprenol to be used according to the invention. It can be used in standard commercial quality and purity in step a) of the process according to the invention. Preference is given to using isoprenol which has a purity of 90% by weight or above, particularly preferably one with a purity of 95 to 100% by weight and very particularly preferably of from 97 to 99.9% by weight, or even more preferably 98 to 99.8% by weight.
[0042] A further starting material for step a) of the process according to the invention is an aldehyde of the formula (V) R 1 —CHO, where R 1 has the meaning given above in formula (V).
[0043] Preferably, R 1 in the compounds of the formula (V) is straight-chain or branched C 1 -C 12 -alkyl or straight-chain or branched C 2 -C 12 -alkenyl. Particularly preferably, R 1 is straight-chain or branched C 1 -C 6 -alkyl or straight-chain or branched C 2 -C 6 -alkenyl. In a further preferred embodiment, R 1 is phenyl.
[0044] Meanings for the radical R 1 that are preferred according to the invention are thus, for example, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, n-pentyl, n-hexyl or n-heptyl, preferably methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, very particularly preferably isobutyl (2-methylpropyl).
[0045] Aldehydes of the formula (V) to be used with preference are: acetaldehyde, valeraldehyde, isovaleraldehyde, pentanal, hexanal, heptanal, benzaldehyde, citral, citronellal. Aldehydes of the formula (V) that are to be used with very particular preference according to the invention are isovaleraldehyde and benzaldehyde, in particular isovaleraldehyde.
[0046] Preferably, in step a), the 3-methylbut-3-en-ol (IV) and the aldehyde (V) are used in a molar ratio of about 1:2 to 2:1, particularly preferably from 0.7:1 to 2:1, in particular from 1:1 to 2:1. In a specific embodiment, in step a), the 3-methylbut-3-en-ol (III) and the aldehyde (V) are used in a molar ratio of from 1:1 to 1.5:1.
[0047] According to the invention, the reaction in step a) takes place in the presence of an acidic catalyst. In principle, for the reaction in step a) any acidic catalyst can be used, i.e. any substance which has Brönstedt or Lewis acidity. Examples of suitable catalysts are protic acids, such as hydrochloric acid, sulfuric acid, phosphoric acid, methanesulfonic acid and p-toluenesulfonic acid, acidic molecular element compounds, such as aluminum chloride, boron trifluoride, zinc chloride, phosphorus pentafluoride, arsenic trifluoride, tin tetrachloride, titanium tetrachloride and antimony pentafluoride; oxidic acidic solid bodies such as zeolites, silicates, aluminates, alumosilicates, clays and acidic ion exchangers.
[0048] Preferably, the acidic catalyst used in step a) is selected from hydrochloric acid, sulfuric acid, methanesulfonic acid, p-toluenesulfonic acid and strongly acidic cation exchangers.
[0049] In a first variant, the reaction in step a) takes place in the presence of a Brönstedt acid, which is preferably selected from hydrochloric acid, sulfuric acid, methanesulfonic acid, p-toluenesulfonic acid. In this first variant, in step a) a solvent can be used which is preferably selected from hydrocarbons and hydrocarbon mixtures. Suitable solvents are, for example, hexane, heptane, ligroin, petroleum ether, cyclohexane, decalin, toluene, xylene and mixtures thereof. Preference is given to using no solvent. Preferably, the catalyst in this first variant is used in an amount of from 0.05 to 5 mol %, particularly preferably from 0.1 to 4 mol %, based on the aldehyde (V). Preferably, the reaction in step a) according to this first variant takes place at a temperature in the range from 20 to 120° C., particularly preferably 30 to 80° C.
[0050] In a second variant, the reaction in step a) takes place in the presence of a strongly acidic cation exchanger. The term strongly acidic cation exchanger here is understood as meaning a cation exchanger in the H + form which has strongly acidic groups. The strongly acidic groups are generally sulfonic acid groups. The acidic groups are generally bonded to a polymer matrix, which may be e.g. gel-like and/or macroporous. A preferred embodiment of the process according to the invention is accordingly characterized in that a strongly acidic cation exchanger that has sulfonic acid groups is used. Suitable strongly acidic cation exchangers are described in WO 2010/133473 and WO 2011/154330, to which reference is made here in its entirety.
[0051] Of suitability for use in step a) are strongly acidic ion exchangers (such as e.g. Amberlyst, Amberlite, Dowex, Lewatit, Purolite, Serdolit), which are based on polystyrene and which comprise copolymers of styrene and divinylbenzene as carrier matrix with sulfonic acid groups in H + form, as well as ion exchanger groups functionalized with sulfonic acid groups (—SO 3 H). The ion exchangers differ in the structure of their polymeric backbones, and a distinction is made between gel-like and macroporous resins. In a specific embodiment, in step a) a perfluorinated polymeric ion exchanger resin is used. Resins of this type are sold e.g. under the name Nafion® by DuPont. An example of such a perfluorinated polymeric ion exchanger resin which may be mentioned is Nafion® NR-50.
[0052] Commercially available strongly acidic cation exchangers suitable for the reaction in step a) are known for example under the trade names Lewatit® (Lanxess), Purolite® (The Purolite Company), Dowex® (Dow Chemical Company), Amberlite® (Rohm and Haas Company), Amberlyst™ (Rohm and Haas Company). Preferred strongly acidic cation exchangers are: Lewatit® K 1221, Lewatit® K 1461, Lewatit® K 2431, Lewatit® K 2620, Lewatit® K 2621, Lewatit® K 2629, Lewatit® K 2649, Amberlite® FPC 22, Amberlite® FPC 23, Amberlite® IR 120, Amberlyst™ 131, Amberlyst™ 15, Amberlyst™ 31, Amberlyst™ 35, Amberlyst™ 36, Amberlyst™ 39, Amberlyst™ 46, Amberlyst™ 70, Purolite® SGC650, Purolite® C100H, Purolite® C150H, Dowex® 50X8, Serdolit® red and Nation® NR-50.
[0053] The strongly acidic ion exchanger resins are usually regenerated with hydrochloric acid and/or sulfuric acid.
[0054] In a specific embodiment, in step a) the 3-methylbut-3-en-ol (IV) and the aldehyde (V) are reacted in the presence of a strongly acidic cation exchanger and in the presence of water. According to a specific embodiment, besides isoprenol (IV) and the aldehyde of the formula (V), water is also additionally added to the reaction mixture.
[0055] In a suitable embodiment, the starting materials are reacted in the presence of at least mol %, preferably of at least 50 mol %, of water. For example, the starting materials are reacted in the presence of from 25 to 150 mol %, preferably from 40 to 150 mol %, particularly preferably from 50 to 140 mol %, in particular from 50 to 80 mol %, of water. Here, the amount of water used refers to the quantitative amount of the starting material optionally used in deficit or, in the case of an equimolar reaction, to the quantitative amount of one of the two.
[0056] Preferably, the reaction is carried out in the presence of about at least 3% by weight, particularly preferably of at least 5% by weight, of added water. The alcohol of the formula (IV) and the aldehyde of the formula (V) are reacted for example in the presence of 3% by weight to 15% by weight of water, preferably from 5% by weight to 12% by weight of water. The percentages by weight given above here are based on the total amount of the reaction mixture, consisting of the components of the formulae (IV) and (V), and also water.
[0057] Above the stated value, the amount of water can be freely chosen and is limited only by processing or cost aspects, if at all, and can moreover be used in a large excess, for example in a 5- to 15-fold excess, or even more. Preferably, a mixture of isoprenol (IV) and the aldehyde of the formula (V), preferably isovaleraldehyde, with the amount of water to be added is prepared such that the added water remains dissolved in the mixture of isoprenol and the aldehyde, i.e. a two-phase system is not present.
[0058] For the reaction of isoprenol (IV) with the aldehyde (V) in step a), the stated starting materials and optionally the added water can be brought into contact with the acidic cation exchanger. Preferably, isoprenol (IV), aldehyde (V) and optionally the added water are used in the form of a mixture in step a). The stated starting materials, i.e. isoprenol (IV) and the aldehyde (V) and the water to be used in the above amount can be brought into contact with one another and/or mixed in any desired order.
[0059] The amount of strongly acidic cation exchanger in step a) is not critical and can be selected freely within wide limits taking into consideration the economic and processing aspect. The reaction can accordingly be carried out either in the presence of catalytic amounts or else in the presence of large excesses of the strongly acidic cation exchanger. Usually, the strongly acidic cation exchanger is used in an amount of from about 5 to about 40% by weight, preferably in an amount of from about 20 to about 40% by weight and particularly preferably in an amount of from about 20 to about 30% by weight, in each case based on the sum of used isoprenol (IV) and aldehyde of the formula (V). Here, the data refer to the ready-to-use cation exchanger, which is generally pretreated with water and accordingly can comprise amounts of up to about 70% by weight, preferably of from about 30 to about 65% by weight and particularly preferably from about 40 to about 65% by weight, of water. Particularly in the case of a discontinuous procedure, an addition of water over and above this can therefore be superfluous when carrying out the process according to the invention. The specified strongly acidic cation exchangers can be used in step a) either individually or else in the form of mixtures.
[0060] In the case of a continuous procedure, the catalyst hourly space velocity is for example in the range from 50 to 2500 mol per m 3 of catalyst and h, preferably in the range from 100 to 2000 mol per m 3 of catalyst and h, in particular in the range from 130 to 1700 mol per m 3 of catalyst and h, where the quantitative amount in mol refers to the starting material of the formula (IV).
[0061] The reaction in step a) in the presence of a strongly acidic cation exchanger can if desired also be additionally carried out in the presence of a solvent that is inert under the reaction conditions. Suitable solvents are, for example, tert-butyl methyl ether, cyclohexane, decalin, hexane, heptane, ligroin, petroleum ether, toluene and xylene. The stated solvents can be used alone or in the form of mixtures with one another. Preferably, the reaction in step a) is carried out in the presence of a strongly acidic cation exchanger without addition of an organic solvent.
[0062] Preferably, the reaction of isoprenol (IV) with the selected aldehyde (V) in step a) is carried out in the presence of water and in the presence of a strongly acidic cation exchanger at a temperature in the range from 0 to 70° C., particularly preferably at a temperature in the range from 20 to 70° C. and in particular at a temperature in the range from 20 to 60° C. This is the temperature of the reaction mixture.
[0063] The reaction in step a) can be carried out discontinuously or continuously. Here, for example in the discontinuous case, the reaction can be performed such that a mixture of isoprenol (IV), the aldehyde (V), optionally water and optionally an organic solvent is charged to a suitable reaction vessel, and the acidic catalyst is added. When the reaction is complete, the catalyst can then be separated off from the resulting reaction mixture by suitable separation processes. The order in which the individual reaction components are brought into contact is not critical and can be varied according to the scale of the particular processing configuration. If a Brönstedt acid, which is preferably selected from hydrochloric acid, sulfuric acid, methanesulfonic acid, p-toluenesulfonic acid, is used as catalyst in step a), then the separating off of the catalyst can take place distillatively e.g. following aqueous work-up or take place directly by distillation. If a strongly acidic cation exchange is used as catalyst in step a), then the separating off of the catalyst can take place e.g. by filtration or by centrifugation.
[0064] In the context of a preferred embodiment, the reaction of isoprenol (IV) with the aldehyde (V) in step a) is carried out continuously. For this, for example a mixture of the starting materials to be reacted of isoprenol and aldehyde of the formula (V) with water can be prepared and this mixture can then continuously be brought into contact with a strongly acidic cation exchanger. For this, the selected cation exchanger can be introduced for example into a suitable through-flow reactor, for example a stirred reactor with feed and discharge or a tubular reactor, and the starting materials and the water can be introduced into these continuously and the reaction mixture can be discharged continuously. Here, the starting materials and the water can be introduced as desired into the through-flow reactor as individual components or else in the form of a mixture as described above. Corresponding processes are described in the European patent applications 13165767.8 and 13165778.5.
[0065] In step a) of the process according to the invention a reaction mixture is obtained which comprises
at least one 2-substituted 4-hydroxy-4-methyltetrahydropyran of the general formula (I) at least one dioxane compound (II)
[0000]
and at least one of the compounds (III.1), (III.2) or (III.3)
[0000]
[0000] in which
R 1 is straight-chain or branched C 1 -C 12 -alkyl, straight-chain or branched C 2 -C 12 -alkenyl, unsubstituted or C 1 -C 12 -alkyl- and/or C 1 -C 12 -alkoxy-substituted cycloalkyl having in total 3 to 20 carbon atoms or unsubstituted or C 1 -C 12 -alkyl- and/or C 1 -C 12 -alkoxy-substituted aryl having in total 6 to 20 carbon atoms.
[0070] Preferably, R 1 is isobutyl. As a rule, the reaction mixture comprises a mixture of the compounds (III.1), (III.2) and (III.3).
[0071] The reaction mixture obtained in step a) of the process according to the invention can comprise at least one compound which is preferably selected from:
3-methylbut-3-en-1-ols of the formula (IV) aldehydes of the formula (V) acetals of the general formula (VI)
[0000]
[0000] in which
R 1 is straight-chain or branched C 1 -C 12 -alkyl, straight-chain or branched C 2 -C 12 -alkenyl, unsubstituted or C 1 -C 12 -alkyl- and/or C 1 -C 12 -alkoxy-substituted cycloalkyl having in total 3 to 20 carbon atoms or unsubstituted or C 1 -C 12 -alkyl- and/or C 1 -C 12 -alkoxy-substituted aryl having in total 6 to 20 carbon atoms.
[0076] Preferably, R 1 is isobutyl.
[0077] The reaction mixture obtained in step a) of the process according to the invention can comprise further components, such as water, organic solvent, etc.
[0078] Preferably, the reaction mixture obtained in step a) comprises the 2-substituted 4-hydroxy-4-methyltetrahydropyran of the formula (I) in an amount of from 50 to 90% by weight, particularly preferably 60 up to about 80% by weight, based on the total weight of the reaction mixture.
[0079] Preferably, the reaction mixture obtained in step a) comprises the dioxane compound of the formula (II) in a total amount of from 5 to 20% by weight, particularly preferably 5 up to about 15% by weight, based on the total weight of the reaction mixture. Preferably, the reaction mixture obtained in step a) comprises the compounds of the formulae (III.1), (III.2) and (III.3) in a total amount of from 5 to 20% by weight, particularly preferably 5 up to about 15% by weight, based on the total weight of the reaction mixture.
[0080] In a typical composition, the reaction mixture obtained in step a) comprises the following compounds, in each case based on the total weight of the reaction mixture:
[0000] 60 to 85% by weight of at least one compound (1),
5 to 15% by weight of at least one compound (II),
5 to 15% by weight of at least one of the compounds (III.1), (III.2) or (III.3),
0 to 10% by weight of at least one 3-methylbut-3-en-1-ol (IV),
0 to 5% by weight of at least one aldehyde (V)
0 to 5% by weight of at least one compound (VI),
2 to 10% by weight of water.
[0081] Preferably, the reaction mixture obtained in step a) comprises:
[0000] 15 to 22% by weight of trans-(I),
45 to 65% by weight of cis-(I),
5 to 15% by weight of at least one compound (II),
5 to 15% by weight of at least one of the compounds (III.1), (III.2) or (III.3),
0 to 10% by weight of at least one 3-methylbut-3-en-1-ol (IV),
0 to 5% by weight of at least one aldehyde (V),
0 to 5% by weight of at least one compound (VI),
2 to 10% by weight of water,
in each case based on the total weight of the reaction mixture.
[0082] Preferably, the reaction mixture obtained in step a) comprises the 2-substituted 4-hydroxy-4-methyltetrahydropyrans of the formula (I) in the form of mixtures of the cis-diastereomers of the formula cis-(I) and of the trans-diastereomers of the formula trans-(I)
[0000]
[0083] where the diastereomer ratio of the cis-diastereomer cis-(I) to the trans-diastereomer trans-(I) is preferably 65:35 to 95:5, particularly preferably 70:30 to 85:15, and R 1 has the meanings given above.
[0084] Preferably, the reaction mixture obtained in step a) comprises 2-isobutyl-4-hydroxy-4-methyltetrahydropyran in the form of mixtures of the cis-diastereomer of the formula cis-(I.a) and of the trans-diastereomer of the formula trans-(I.a)
[0000]
[0000] where the diastereomer ratio of the cis-diastereomer cis-(I.a) to the trans-diastereomer trans-(I.a) is preferably 65:35 to 95:5, particularly preferably 70:30 to 85:15.
[0085] On account of their particular odor properties, mixtures of this kind are suitable to a particular degree for use as aroma chemicals, for example as components with lily of the valley scent for producing fragrance compositions.
Acid Treatment
[0086] According to the invention, the reaction mixture from step a), prior to use in step b) and/or during use in step b), is brought into contact with an acidic ion exchanger and/or admixed with a strong acid.
[0087] In a first variant, the treatment of the reaction mixture from step a) with at least one acidic component takes place in homogeneous phase. in the event of the treatment according to the invention in homogeneous phase, the interacting components are present in the liquid phase. For this, a liquid reaction mixture from the reaction of 3-methylbut-3-en-1-ol (IV) with an aldehyde (V) or a liquid fraction obtained by distillative separation of such a reaction mixture can be admixed with a strong acid which, under the treatment conditions, is at least partially miscible with the reaction mixture or a fraction of the reaction mixture or is at least partially soluble in this.
[0088] In a second variant, the treatment of the reaction mixture from step a) with at least one acidic component takes place in heterogeneous phase. In the case of the treatment according to the invention in heterogeneous phase, the interacting components are generally present partly in the liquid phase and partly in the solid phase. For this, a liquid reaction mixture from the reaction of 3-methylbut-3-en-1-ol (IV) with an aldehyde (V) or a liquid fraction obtained by distillative separation of such a reaction mixture can be brought into contact with an acid present in solid form. Preferably, the acid for the treatment is used in solid phase in the form of a fixed bed. Preference is given to using an acidic ion exchanger for the treatment in solid phase.
[0089] Suitable strong acids and strong ion exchangers are the acidic catalyst specified above in step a). Reference is hereby made to these in their entirety.
[0090] Preferably, according to the first variant, the reaction mixture from step a), prior to use in step b), or a fraction obtained during the distillative separation in step b) is admixed with a strong acid. In a preferred embodiment, the reaction mixture from step a), prior to use in step b), is admixed with a strong acid. Alternatively, it is possible to admix the bottom of the distillative separation in step b) or, in the case of a multistage distillation, the bottom of the first distillation stage of the distillative separation in step b) with a strong acid.
[0091] Preferably, the reaction mixture from step a) is admixed, according to the first variant, with a strong acid which is selected from sulfuric acid, hydrochloric acid, methanesulfonic acid and p-toluenesulfonic acid.
[0092] Particularly preferably, the reaction mixture from step a) is admixed with sulfuric acid prior to use in step b).
[0093] Preferably, the reaction mixture from step a), prior to use in step b), is admixed with 1 to 250 ppm by weight, preferably with 2 to 100 ppm by weight, based on the total weight of the reaction mixture, of a strong acid. Alternatively, it is possible to admix the bottom of the distillative separation in step b) or, in the case of a multistage distillation, the bottom of the first distillation stage of the distillative separation in step b) with 1 to 250 ppm by weight, preferably with 2 to 100 ppm by weight, based on the total weight of the bottom product, of a strong acid. The quantitative data refers here to the pure acid. Of course it is possible and frequently preferred to use the acid in dilute form, specifically as aqueous solution.
[0094] According to the second variant described above, the reaction mixture from step a) is brought into contact with an acidic ion exchanger prior to use in step b).
[0095] The contacting with the acidic ion exchanger can take place discontinuously or continuously. Preference is given to continuous contacting.
[0096] Preferably, the contacting takes place at a temperature of from 30 to 80° C., particularly preferably from 40 to 70° C.
[0097] Suitable ion exchangers are the aforementioned strongly acidic cation exchangers. The use amount of acidic ion exchanger here is generally not critical. The reaction can accordingly be carried out either in the presence of catalytic amounts, or else in the presence of an excess, of a strongly acidic cation exchanger.
[0098] In particular, the reaction mixture from step a) is not subjected to a distillative separation before bringing it into contact with an acidic ion exchanger and/or admixing it with a strong acid.
Step b)
[0099] Preferably, in step b) of the process according to the invention, the reaction mixture from step a) is subjected to a distillative separation. Suitable devices for the distillative separation comprise distillation columns, such as tray columns which can be equipped with bubble caps, sieve plates, sieve trays, packings, packing bodies, valves, side take-off, etc., evaporators, such as thin-film evaporators, falling-film evaporators, forced-circulation evaporators, Sambay evaporators, etc., and combinations thereof.
[0100] The distillation columns can have separation-effective internals, which are preferably selected from separation trays, arranged packings, e.g. sheet-metal or fabric packings, such as Sulzer Mellapak®, Sulzer BX, Montz B1 or Montz A3 or Kühni Rombopak, or random beds of packings, such as e.g. Dixon rings, Raschig rings, high-flow rings or Raschig super rings. Arranged packings have proven to be particularly successful, preferably sheet-metal or fabric packings, with a specific surface area of from 100 to 750 m 2 /m 3 , in particular 250 to 500 m 2 /m 3 . They bring about high separation efficiencies coupled with low pressure losses.
[0101] Preferably, for the separation in step b), a device is used which comprises
a feed column with rectification section situated above the feed point and stripping section situated below the feed point, an upper combining column communicating with the upper end of the rectification section and a lower combining column communicating with the lower end of the stripping section, and a discharge column communicating with the upper combining column and the lower combining column.
[0105] Preferably, the separation in step b) takes place by
i) introducing the reaction product from step a) into a feed column with rectification section situated above the feed point and stripping section situated below the feed point, ii) providing an upper combining column communicating with the upper end of the rectification section and with condenser at the upper column end and a lower combining column communicating with the lower end of the stripping section and with heater at the lower column end, iii) providing a discharge column communicating with the upper combining column and the lower combining column which has at least one side take-off, iv) drawing off from the discharge column at the top or in the upper region compounds which boil more readily than the 2-substituted 4-hydroxy-4-methyltetrahydropyrans (I), drawing off, as at least one side take-off, at least some of the 2-substituted 4-hydroxy-4-methyltetrahydropyrans (I), and drawing off, in the bottom or in the lower region of the lower combining column, the 2-substituted 4-hydroxy-4-methyltetrahydropyrans (I) which have not been drawn off as side take-off and drawing off the compounds which have a higher boiling point than the 2-substituted 4-hydroxy-4-methyltetrahydropyrans (I).
[0110] In a preferred embodiment, the discharge removed from the discharge column at the top or in the upper region comprises:
at least some or the total amount of the dioxane compound (II) present in the reaction product from step a), at least some or the total amount of the compounds (III.1), (III.2) and (III.3) present in the reaction product from step a), if present, unreacted 3-methylbut-3-en-1-ol of the formula (IV), if present, unreacted aldehyde (V), small amounts or no 2-substituted 4-hydroxy-4-methyltetrahydropyrans (I), water.
[0117] In a particularly preferred embodiment, 3-methylbut-3-en-1-ol of the formula (IV) and isovaleraldehyde (V) are used for the reaction in step a). The discharge removed from the discharge column at the top or in the upper region then comprises:
at least some or the total amount of the dioxane compound (II) present in the reaction product from step a), in which R 1 is isobutyl, at least some or the total amount of the compounds (III.1), (III.2) and (III.3) present in the reaction product from step a), in which R 1 is isobutyl, if present, unreacted 3-methylbut-3-en-1-ol of the formula (IV), if present, unreacted isovaleraldehyde (V), small amounts or no 2-(2-methylpropyl)-4-hydroxy-4-methyltetrahydropyran of the formula (I.a), water.
[0124] The thus obtained top product can be subjected to a phase separation to separate off the majority of the water. Apart from such a phase separation, the thus obtained top product can generally be subjected to further processing without further work-up. This includes a hydrogenation to 2-substituted 4-methyltetrahydropyrans (VII) and specifically 2-(2-methylpropyl)-4-methyltetrahydropyran (dihydrorose oxide). If desired, the top product can be subjected to a further work-up to separate off at least some of the components different from the compounds (II), (III.1), (III.2) and (III.3). For this, the top product can be subjected e.g. to a further distillative separation.
[0125] In a preferred embodiment, one side stream is drawn off from the discharge column or two side streams are drawn off from the discharge column. In a specific embodiment, only one side stream is drawn off from the discharge column.
[0126] If, in step b), two or more discharges are removed which comprise 2-substituted 4-hydroxy-4-methyltetrahydropyrans (I), e.g. two different side take-offs or one side take-off and one bottom take-off, then these generally differ as regards the composition of the stereoisomers. Consequently, the isolation of a fraction enriched in cis-diastereomers compared to the reaction product from step a) and a fraction enriched in trans-diastereomers is possible. If the separation efficiency of the distillation apparatus used is adequate, at least one of the diastereomers can, if desired, be obtained in pure form.
[0127] The feed column, discharge column, upper combining column and lower combining column can be discrete design elements or be configured as a section or chamber of a distillation column which combines several functions. The expression “communicating columns” means that between them there is an exchange both of rising vapors as well as that of descending condensate.
[0128] In a preferred embodiment of the process according to the invention, the distillative separation in step b) takes place in an arrangement of distillation columns which comprises a dividing-wall column or an interconnection of at least two thermally coupled conventional distillation columns.
[0129] Dividing-wall columns are special distillation columns with at least one feed point and at least three removal points, in which the so-called rectification region is located between evaporator and condenser and in which some of the condensate formed in the condenser moves downwards in liquid form as reflux in countercurrent to the vapors rising from the evaporation device and which comprises, in a part region of the column, below and/or above the feed point at least one separation device (dividing wall) operating in the longitudinal direction for preventing crossmixing of liquid stream and/or vapor stream (steam stream) and which thus facilitate distillative separation of substance mixtures. The basic principle of dividing-wall columns has been known for a long time and is described for example in U.S. Pat. No. 2,471,134, in EP-A-0 122 367 or in G. Kaibel, Chem. Eng. Technol. Vol. 10, 1987, pages 92 to 98.
[0130] The general basic design of a dividing-wall column comprises at least one side feed point on one side of the dividing wall and at least three removal points, at least one of which is located on the other side of the dividing wall. Since in this design a crossmixing of liquid stream and/or vapor stream is prevented in the region of the dividing wall, it is possible to obtain the side products in pure form. In the event of separating multimaterial mixtures, this generally enables the number of distillation columns required overall to be reduced. Moreover, when using dividing-wall columns, investment costs as well as energy can be saved compared with a simple serial connection of two conventional distillation columns (see M. Knott, Process Engineering, Vol. 2, 1993, February, pages 33 to 34).
[0131] In the context of the invention, conventional distillation columns is the term used to denote all distillation columns which comprise no dividing wall. In thermally coupled conventional distillation columns, mass streams and energy streams are mutually exchanged. Consequently, compared with a simple serial connection of conventional distillation columns a considerable saving of energy is possible. A preferred alternative to the dividing-wall column is a connection of two thermally coupled distillation columns. An overview of various arrangements is given for example in G. Kaibel et al., Chem.-Ing.-Tech., Vol. 61, 1989, pages 16 to 25 and G. Kaibel et al., Gas Separation & Purification, Vol. 4, 1990, June, pages 109 to 114.
[0132] In a first preferred embodiment, a distillation column with a thermally coupled precolumn is used for the distillation, i.e. the discharge column, the upper combining column and the lower combining column are designed as a single-section distillation column, and the feed column is designed as a precolumn to the distillation column. In a second preferred embodiment, a distillation column with a thermally coupled post-column is used, i.e. the feed column, the upper combining column and the lower combining column are configured as a single-section distillation column, and the discharge column is configured as a post-column to the distillation column. Distillation columns with attached auxiliary columns are known and are described e.g. in Chem. Eng. Res. Des., Part A: Trans IChemE, March 1992, pp. 118-132, “The design and optimization of fully thermally coupled distillation columns”.
[0133] It has proven to be favorable to remove at least some of the compounds which boil more easily than the 2-substituted 4-hydroxy-4-methyltetrahydropyrans (I) from the reaction product from step a) prior to introduction into the feed column. In a specific embodiment, for the distillative separation of the reaction product from step a), an arrangement of distillation columns is therefore used which comprises an upstream conventional distillation column and a downstream dividing-wall column and a downstream interconnection of two thermally coupled conventional distillation columns.
[0134] Preferably, for the distillative separation in step b)
b1) the reaction mixture from step a) is initially subjected to a separation in a conventional distillation column, where a first top product is obtained which is enriched in the dioxane compound (II) and the compounds (III.1), (III.2) and (III.3) and comprises essentially no compounds of the general formula (I), and a first bottom product is obtained which is depleted in the dioxane compound (II) and the compounds (III.1), (III.2) and (III.3) and comprises the majority of the compounds of the general formula (I), b2) the first bottom product from step b1) is subjected to a separation in a dividing-wall column or in an interconnection of two thermally coupled conventional distillation columns, where a second top product is obtained which comprises the compounds (II), (III.1), (III.2), (III.3) not present in the first top product, as well as optionally small amounts of the compounds of the general formula (I), a side stream is obtained which consists essentially of compound of the general formula (I), and a second bottom product is obtained which comprises the compounds of the general formula (I) which are not present in the top product and not present in the side stream.
[0137] Preferably, also in the aforementioned embodiment, in the compounds of the formulae (I), (II), (III.1), (III.2) and (III.3) R 1 is isobutyl.
[0138] The expression according to which the first top product comprises essentially no compounds of the general formula (I) means that the fraction of compounds of the general formula (I) in the first top product is at most 5% by weight, particularly preferably at most 2% by weight, in particular at most 1% by weight, specifically at most 0.1% by weight, based on the total weight of the first top product. In a special embodiment, the first top product comprises no compounds of the general formula (I).
[0139] The second top product can comprise for example 1 to 40% by weight, particularly preferably 2 to 30% by weight, in particular 5 to 25% by weight, specifically 10 to 20% by weight, of compounds of the general formula (I), based on the total weight of the second top product.
[0140] In a specific embodiment, the side stream consists only of compounds of the general formula (I).
[0141] In a further special embodiment, the second bottom product can comprise compounds which have a higher boiling point than the compounds of the general formula (I).
[0142] The fraction(s) obtained in step b) of the 2-substituted 4-hydroxy-4-methyltetrahydropyrans of the general formula (I) are advantageously characterized by a significantly reduced content, compared with the starting material, of components which do not adversely affect the odor impression. In particular, the occurrence of cheesy notes can be effectively presented. The fraction(s) obtained in step b) of the 2-substituted 4-hydroxy-4-methyltetrahydropyrans of the general formula (I) can in many cases be supplied for commercial use even without further work-up.
[0143] The fraction(s) obtained in step b) of the 2-substituted 4-hydroxy-4-methyltetrahydropyrans of the general formula (I) can if desired be subjected to a further work-up. For this, the fractions can be used individually or after a (partial) combining. The customary purification processes known to the person skilled in the art are suitable. These include, for example, a distillation, an extraction or a combination thereof.
[0144] A specific embodiment relates to a process in which the reaction mixture from step a) treated with acid is subjected to a distillative separation in an interconnection of distillation columns which comprises
a conventional distillation column, a first dividing-wall column or a first interconnection of two thermally coupled conventional distillation columns, and a second dividing-wall column or a second interconnection of two thermally coupled conventional distillation columns.
[0148] A further special embodiment relates to a process in which the reaction mixture from step a) treated with acid
is subjected to a first distillative separation, where a first top product is obtained which is enriched in the dioxane compound (II) and the compounds (III.1), (III.2) and (III.3) and comprises essentially no compounds of the general formula (I), and a first bottom product is obtained which is depleted in the dioxane compound (II) and the compounds (III.1), (III.2) and (III.3) and comprises the majority of the compounds of the general formula (I), the first bottom product is admixed with at least one base or subjected to a simple distillation, where the majority of the first bottom product is evaporated and then condensed, the first bottom product admixed with base or the condensate is subjected to a further distillative separation.
[0152] Suitable bases for addition to the first bottom product are alkali metal bases such as sodium hydroxide solution, potassium hydroxide solution, sodium carbonate, sodium hydrogen carbonate, potassium carbonate or potassium hydrogen carbonate and alkaline earth metal bases such as calcium hydroxide, calcium oxide, magnesium hydroxide or magnesium carbonate, and also amines. The base is particularly preferably selected from Na 2 CO 3 , K 2 CO 3 , NaHCO 3 , KHCO 3 , NaOH, KOH and mixtures thereof.
[0153] Preferably, the first bottom product following the addition of base has a pH in the range from 4 to 7.
[0154] In a specific embodiment, the first bottom product is brought into contact with a bed of at least one base.
[0155] In the context of the invention, a simple distillation is understood as meaning a distillation in which, unlike during the rectification or countercurrent distillation, some of the condensate is returned again countercurrently to the rising vapors of the boiling mixture, but where the bottom product is for the most part evaporated and then condensed. In a preferred embodiment, a Sambay evaporator is used.
[0156] The amount of first bottom product which is evaporated comprises preferably 60 to 99.9% by weight, particularly preferably 75 to 99% by weight, in particular 90 to 98% by weight, of the total amount of the bottom product.
[0157] The first bottom product admixed with base or the condensate is preferably subjected to a further distillative separation in a dividing-wall column or in an interconnection of two thermally coupled conventional distillation columns. Here, a second top product is preferably obtained which comprises the compounds (II), (III.1), (III.2), (III.3) not present in the first top product, and also optionally small amounts of the compounds of the general formula (I), a side stream which consists essentially of compound of the general formula (I) and a second bottom product which comprises the compounds of the general formula (I) which are not present in the top product nor in the side stream.
[0158] The compositions according to the invention and the compositions obtainable by the process according to the invention are particularly advantageously suitable as fragrance or for providing a fragrance.
[0159] In this connection, in addition to the 2-substituted 4-hydroxy-4-methyltetrahydropyrans of the general formula (I), the fraction obtained in step b), is enriched in at least one of the compounds (III.1), (III.2) or (III.3), can be subjected to further processing for the provision of a fragrance. Thus, as a result of hydrogenation of the compounds (III.1), (III.2) or (III.3), a hydrogenation product is obtained which comprises at least one 2-substituted 4-methyltetrahydropyran of the general formula (VII)
[0000]
[0000] in which
R 1 is straight-chain or branched C 1 -C 12 -alkyl, straight-chain or branched C 2 -C 12 -alkenyl, unsubstituted or C 1 -C 12 -alkyl- and/or C 1 -C 12 -alkoxy-substituted cycloalkyl having in total 3 to 20 carbon atoms or unsubstituted or C 1 -C 12 -alkyl- and/or C 1 -C 12 -alkoxy-substituted aryl having in total 6 to 20 carbon atoms.
[0161] In particular, R 1 is isobutyl. This compound, referred to as dihydrorose oxide, is suitable on account of its particular odor properties with a rose scent-like character to a particular extent for use as aroma chemical and specifically for producing fragrance compositions.
[0162] This specific embodiment advantageously permits an integrated process for the simultaneous production of 2-substituted 4-hydroxy-4-methyltetrahydropyrans (I) and of 2-substituted 4-methyltetrahydropyrans (VII).
[0163] The present invention thus relates, in the context of a specifically preferred embodiment, to a process for the preparation and isolation of 2-(2-methylpropyl)-4-hydroxy-4-methyltetrahydropyran of the formula (I.a) and of dihydrorose oxide (VII.a)
[0000]
[0164] The compositions according to the invention can be diluted as required for use as fragrance with at least one solvent customary in this field of application. Examples of suitable solvents are: ethanol, dipropylene glycol or ethers thereof, phthalates, propylene glycols, or carbonates of diols, preferably ethanol. Water is also suitable as solvent for diluting the fragrance compositions according to the invention and can advantageously be used together with suitable emulsifiers.
[0165] On account of the structural and chemical similarity of the components, the fragrances obtained by the process according to the invention have high stability and durability.
[0166] The isomer mixtures obtainable by the process according to the invention of 2-(2-methylpropyl)-4-hydroxy-4-methyltetrahydropyran of the formula (I.a) are characterized by a pleasant lily of the valley scent. The isomer mixtures obtainable by the process according to the invention of 2-(2-methylpropyl)-4-methyltetrahydropyran of the formula (VII.a) (dihydrorose oxide) are characterized by a pleasant rose-like character.
[0167] The fragrances obtained by the process according to the invention are suitable for incorporation into cosmetic compositions as well as utility and consumer goods and/or compositions as are described in more detail below, it being possible to incorporate the fragrances into said products or else to apply them thereto. In the context of the entire present invention, an organoleptically effective amount here is to be understood in particular as meaning an amount which, upon use as directed, suffices to bring about a scent impression for the user or consumer.
[0168] All customary cosmetic compositions are suitable as cosmetic compositions. These are preferably perfume, eau de toilette, deodorants, soap, shower gel, bath gel, creams, lotions, sunscreens, compositions for the cleaning and care of hair such as hair shampoo, conditioner, hair gel, hair setting compositions in the form of liquids or mousses and further cleaning or care compositions for hair, compositions for decorative application on the human body, such as cosmetic sticks, for example lip sticks, lip care sticks concealing sticks (concealers), blusher, eye shadow pencils, lip liner pencils, eye liner pencils, eyebrow pencils, correction pencils, sunscreen sticks, anti-acne sticks and comparable products, as well as nail varnishes and further products for nail care.
[0169] The fragrances obtained by the process according to the invention are specifically suitable for use in perfumes, e.g. as eau de toilette, shower gels, bath gels and body deodorants.
[0170] They are furthermore suitable for the aromatization of consumer or utility goods into which they are incorporated and/or onto which they are applied and thereby impart a pleasant fresh green accent to them. Examples of consumer or utility goods are: air fresheners (air care), cleaning compositions or care compositions for textiles (specifically detergents, fabric softeners), textile treatment compositions such as, for example, ironing aids, scouring compositions, cleaning compositions, care compositions for treating surfaces, for example furniture, floors, kitchen appliances, glass panes and windows as well as screens, bleaches, toilet blocks, anti-limescale compositions, fertilizers, construction materials, mold removers, disinfectants, products for car or automobile care and more besides.
[0171] The examples below serve to illustrate the invention without limiting it in any way.
EXAMPLES
[0172] Gas chromatographic analyses were carried out according to the following method:
[0000] Column: DB WAX 30 m×0.32 mm;
FD 0.25 μm;
[0173] Injector temperature: 200° C.; detector temperature 280° C.;
Temperature program: Starting temp.: 50° C., at 3° C./min to 170° C.,
at 20° C./min to 230° C., 7 min isotherm;
Retention times: Isovaleraldehyde t R =3.7 min
cis-Dihydrorose oxide t R =8.4 min trans-Dihydrorose oxide t R =9.6 min 4,4-Dimethyl-2-isobutyl-1,3-dioxane t R =11.9 min
[0178] Concentrations of the resulting crude products (% by weight) were ascertained by GC analysis with an internal standard.
Example 1
According to the Invention
[0179] A mixture of isovaleraldehyde (112.5 g, 1.31 mol), isoprenol (125 g, 1.45 mol) and 12.5 g of water was reacted in the presence of 50 g of the strongly acidic cation exchanger Amberlyst® 131, as described in example 1 of WO2011/154330.
[0180] The resulting crude product had the following composition:
[0000] 19.5 GC area % trans-pyranol (I)
56.1 GC area % cis-pyranol (I)
9.0 GC area % dihydropyran isomers 1-3
8.2 GC area % 1,3-dioxane
0.7 GC area % isovaleraldehyde
1.3 GC area % isoprenol
0.5 GC area % acetal
8.7% water (Karl-Fischer method)
[0181] The crude product was subjected to a distillative separation in an arrangement of a conventional distillation column and a dividing-wall column. The laboratory apparatus consisted of two laboratory columns. The separation efficiency of the first column corresponds to approximately 15 theoretical trays. For the separation of the two phases of the top condensate, a glass phase separator was incorporated. The lower aqueous phase was discharged in a level-controlled manner. The upper organic phase was divided with the help of a reflux divider in a fixed ratio, with some being separated off as top product and the remainder being returned to the column at the top. The feed to the column was carried out between the two column units. The feed stream was conveyed at room temperature. The flow rate was 1000 g/h.
[0182] 10 ppm by weight of sulfuric acid as 1% strength solution in water were added to the crude product.
[0183] The column was operated at a top pressure of 50 mbar and a reflux amount of 360 g/h. Here, a pressure loss of about 3.1 mbar was established. At the top of the column, a temperature of 70° C. was measured, and in the bottom a temperature of 131° C. was measured. The bottom discharge amount was fixed at 776 g/h. The top discharge amount was 131 g/h.
[0184] The fractions obtained were analyzed by gas chromatography with the help of a standard GC. Gas chromatographic analyses were carried out according to the following method:
[0000] Column: DB WAX 30 m×0.32 mm; FD 0.25 μm; Inj. 200° C., Det. 280° C.; 50° C., 3°/′ to 170° C.-20°/′ to 230° C.-7 min isoth., t R =min; t R (isovaleraldehyde): 3.8; t R (dihydropyranisomers): 10.1; 12.0; 12.4; t R (isoprenol): 10.7; t R (1,3-dioxane): 12.2; t R (acetal): 24.8; t R (trans-pyranol): 28.5; t R (cis-pyranol): 30.0; concentrations of the resulting crude products (% by weight) were determined by GC analysis by means of an internal standard.
[0185] The top stream drawn off from the phase separator at the top of the column comprised:
[0000] 1.2% water (Karl-Fischer method)
3.8 GC area % isovaleraldehyde
44.3 GC area % dihydropyran isomers 1-3
8.9 GC area % isoprenol
38.9 GC area % 1,3-dioxane
[0186] The following were found in the bottom discharge column
[0000] 0.04 GC area % isoprenol
2.37 GC area % dihydropyran isomers
2.1 GC area % 1,3-dioxane
23.5 GC area % trans-pyranol
67.4 GC area % cis-pyranol.
[0187] The distillation yield as regards cis- and trans-pyranol was 100%.
[0188] The second laboratory column was configured as a dividing-wall column. The separation efficiency in the dividing wall region was about 32 theoretical plates. The total number of theoretical plates including the dividing-wall region was about 50. The feed was added at the height of the middle of the dividing wall section. The feed stream used was the mixture from the bottom discharge of the first column. The feed flow rate was 302.4 g/h. The column was operated at a top pressure of 10 mbar and a reflux of 400 g/h. At the top of the column, a temperature of 72° C. was measured and in the bottom a temperature of 124° C. (±0.5 K) was measured. The bottom discharge was adjusted to 14 g/h (±1 g/h) and the distillate removal was adjusted to 26 g/h (±1 g/h).
[0189] The reflux ratio was thus about 15:1. The liquid was divided above the dividing wall in a ratio of 1:2 (feed section:removal section). On the side of the dividing wall opposite the addition side, a liquid side take-off was removed at the same height as the feed stream. The flow rate was fixed at 261 g/h.
[0190] The pure product obtained at the side take-off comprised:
[0000] 24.6 GC area % trans-pyranol and
74.7 GC area % cis-pyranol
[0191] Olfactory assessment of the pure product:
[0192] Smelling strip test 30 min: corresponds to the desired specification
[0000] Gas space test: corresponds to the desired specification
[0193] The distillation yield as regards cis- and trans-pyranol was about 97.5%.
Example 2
Comparison
[0194] The procedure was as in example 1 but no sulfuric acid was added to the crude product used for the distillation.
[0195] The pure product obtained at the side take-off of the dividing-wall column comprised:
[0000] 25.5 GC area % trans-pyranol and
73.6 GC area % cis-pyranol
[0196] Olfactory evaluation of the pure product;
[0197] Smelling strip test 30 min: does not correspond to the specification
[0198] Gas space test: does not correspond to the specification
[0199] The distillation yield as regards cis- and trans-pyranol was about 98.0%. | The present invention relates to a method for the production of 2-substituted 4-hydroxy-4-methyltetrahydropyrans from the acid-catalyzed reaction of 3-methylbut-3-ene-1-ol with an aldehyde, a stable odoriferous quality being achieved and avoiding off-odors that interfere with the odor sensation. | 2 |
CROSS REFERENCES TO RELATED APPLICATIONS
This application is a continuation of application Ser. No. 09/212,634, filed on Dec. 16, 1998, now U.S. Pat. No. 6,193,410.
FIELD OF THE INVENTION
1. Background of the Invention
The invented apparatus and methods pertain to the sport of paint ball which has been receiving growing popularity. In most paint ball sports events, each player has a gun loaded with paint balls which the player shoots at opposing players. The paint balls splatter upon impact and can be used to easily determine whether a player has been eliminated or not from the game.
2. Description of the Related Art
Paint balls are essentially spheres with gelatin or other breakable outer material shells that encapsulate liquid paint or dye. After manufacture, paint balls often sit in storage boxes for extended periods of time. The inventor has been found that over time the heavier constituents of the paint balls' liquid contents will settle under gravity, causing the weight of the paint ball to become unevenly distributed. Also, the outer coatings of paint balls can develop dimples by sitting in the same position for substantial periods of time in storage boxes, for example. The uneven weight distribution and/or dimples of the paint balls cause them to fly erratically when shot from the gun, or to jam when feeding into the gun. In addition, uneven weight distribution or dimples in the paint balls can cause the paint balls to fly too fast or too slowly from the gun. Immediately before and after a paint ball game, the velocities at which the paint balls are shot from the players' guns are tested by referees using a chronograph, and if a player's gun fires at velocities over a specified limit, the player is disqualified from the game or penalized. Conversely, a paint ball which shoots too slowly from a gun can cause a player too miss opportunities to hit opposing players during the game. There is currently no device or method available for solving the settling or dimple problems that occur when storing paint balls. It would be desirable to provide an apparatus and method which can overcome these problems.
SUMMARY OF THE INVENTION
The present invention overcomes the above-noted disadvantages. The invented apparatus includes a support member, a motor, and a container. The motor is mounted to the support member, and the container is coupled to and supported for rotation by the support member and the motor's drive shaft. Paint balls are placed in the container, and the apparatus is operated by activating the motor to rotate the container via the drive shaft, causing the paint balls to move with the container. As the paint balls move, their liquid contents are agitated and mixed so that the weights of the paint balls become evenly distributed. In addition, after moving the paint balls in the container, the paint balls are likely to be resting in different positions than before the container was rotated, a fact which helps to prevent the formation of dimples that would cause the paint ball to jam in a paint ball gun or to fly erratically when shot from the gun. Also, the rolling action of the paint balls as the apparatus' container moves helps to “work out” dimples in the paint balls by the centrifugal force of the paint ball's liquid contents which push the dimples in the paint balls' shells outwardly relative to the paint balls' center to cause the shells to assume dimple-free spherical shapes. The invented apparatus can therefore be used to extend the useful life of paint balls by repairing dimpled paint balls and by mixing the paint balls' liquid contents to become more evenly distributed so that the paint balls will fly in true trajectories at consistent velocities without jamming in paint ball guns.
In the preferred embodiments of the invented apparatus, the motor is driven by an electric power source such as a wall outlet or car battery. The apparatus can include a switch mounted to the support member, which can be operated by a user to electrically couple or decouple the motor from the power source to commence or stop rotation of the container, respectively. The apparatus can also include a timer unit electrically coupled between the motor and the power source, which can be set by a user to supply power from the source to the motor for a predetermined period of time, preferably from ten to fifteen minutes for relatively recently-manufactured paint balls, and from several hours to days for older paint balls. In addition, the timer unit can be set by a user to rotate the container for the predetermined time period repeatedly at a predetermined time interval, such as on a daily basis, for example. The apparatus can also include a transformer electrically coupled between the power source and the motor, that converts the voltage and current level of the power source (typically a wall outlet or a 12-volt car battery) to a voltage and current level that are compatible with the motor. In addition, if the power source generates an alternating-current (AC) electric power and the motor operates on direct current (DC) electric power, the apparatus can include a rectifier coupled between the power source and the motor, to convert the AC power to DC power appropriate for the DC motor. To avoid risk of damaging the paint balls, the motor preferably rotates the container at from one-quarter (¼) to twenty (20) revolutions per minute (RPM), the most preferred range being between six (6) and eight (8) RPMs.
In one preferred embodiment of the invented apparatus, the support member is approximately U-shaped cross-section and includes first and second rigid planar opposing side members, and a rigid planar base member extending between the first and second side members. The base member serves to support the apparatus on a surface such as a table top or floor, for example. The motor is mounted for support to the first side member. The apparatus further includes a support shaft that is rotatably mounted to the second side member, which engages with the container. The container is supported between the motor's drive shaft and the support shaft both for support and to permit rotation of the container relative to the support member. The container preferably has the shape of a rectangular box sized to receive a standard-size case of paint balls. The container can include a first part that has rigid planar first and second side, rear and bottom portions, with the first side portion being coupled to the drive shaft and with the second side portion coupled to the support shaft. The container can also include a second part that defines rigid planar top and front portions of the container. The container can further include a hinge attached between the first and second parts, to allow a user to rotate the second part relative to the first part to open or close the container. In addition, the container can include a securing device such as a latch to releasably secure the first and second parts together to secure the container in its closed position.
In a second embodiment of the invented apparatus, the support member is approximately U-shaped in cross-section and includes opposing rigid planar front and rear members, and a rigid planar base member extending between the front and rear members. The base member serves to support the apparatus on a surface. The motor is mounted to the rear member. The apparatus further includes first and second wheels rotatably mounted to the front member in a spaced relationship. In the second embodiment, the container includes a bucket for containing the paint balls, which has a cylindrical side surface and a planar bottom surface. The bottom surface defines a keyed recess that receives the drive shaft of the motor. The cylindrical surface contacts the first and second wheels to support the container, and is driven by the motor via the drive shaft in contact with the first and second wheels to rotate the bucket and the paint balls contained therein during operation of the apparatus. The bucket can include a lid which can be removably secured to the open top of the bucket to contain paint balls therein so that they will not be spilled out of the bucket during operation of the apparatus. Preferably, the bucket includes at least one agitator attached to an inner surface of the bucket, to move the paint balls as the bucket is rotated by the motor. The agitator is preferably composed of soft material such as neoprene or foam rubber to avoid damaging the paint balls, and has a spiral configuration. Also preferred, the bucket can be lined with a soft material such as neoprene to prevent the paint balls from being damaged. When the motor is stopped, the bucket can be pulled by hand away from and clear of the drive shaft and the wheels, and the bucket can be set upon its bottom surface in an upright position from which the paint balls can be readily retrieved for use in paint ball guns.
The invented method includes a step of placing paint balls in a container, and a step of moving the container to put the paint balls in motion to agitate the liquid contents thereof. The agitation of the paint balls' liquid contents mixes such contents so that their weights are evenly distributed, and also causes the paint balls' contents to push outwardly from the paint balls' center by centrifugal force to push out dimples formed in the paint balls' outer shells. In addition, after moving the paint balls in the container, it is likely that the paint balls will come to rest in a different position than they had prior to moving the container so that the formation of dimples on the paint balls is prevented in the invented method.
These together with other features and advantages, which will become subsequently apparent, reside in the details of construction and operation as more fully hereinafter described and claimed, reference being made to the accompanying drawings, forming a part hereof wherein like numerals refer to like parts throughout the several views.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a first embodiment of the invented apparatus with the container in its closed position;
FIG. 2 is a perspective view of the first embodiment of the invented apparatus with the container in its opened position;
FIG. 3 is a side elevational view of the second embodiment of the invented apparatus;
FIG. 4 is a front elevational view of the second embodiment of the invented apparatus; and
FIG. 5 is a block diagram of the invented apparatus.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
As used herein, the terms “mounted”, “coupled”, “attached” or “engaged” refer to the joining of two elements together, whether in a fixed or releasable manner, through any device or technique, such as through rivets, pins, screws, nuts and bolts, adhesives, welding, fusing, releasable couplers, keyed interlocking parts, or by forming the elements integrally together when manufactured. “Electrically coupled” refers to coupling two elements together, such as by conductive wire cord, so as to actually pass or provide the capability to pass electric power therethrough. “Electrically decoupled” refers to disabling two elements from passing electric power therebetween.
Referring to FIG. 1, a first embodiment of the invented apparatus 1 is shown. The apparatus 1 includes a support member 2 which preferably has an approximately U-shaped cross-section, and which includes two spaced and opposing rigid planar side members 3 , 4 , and a rigid planar base member 5 extending between the side members. The members 3 , 4 , 5 are preferably composed of a rigid material such as aluminum, steel or other metal, or a plastic such as polycarbonate, polyvinyl chloride (PVC), or vinyl, for example. The members 3 , 4 , 5 can be formed as an integral molded, extruded or cast piece of material, or in the case of a metal, can be formed from a single piece of metal that is bent to define the members 3 , 4 , 5 . Alternatively, the members 3 , 4 , 5 can be cut, cast or molded as different material pieces and attached together at their edges to form the support member 2 . The apparatus 1 also preferably includes a switch unit 6 , a timer unit 7 , and a motor 8 . The units 6 , 7 , 8 can be mounted to the side member 3 . The switch unit 6 is electrically coupled to an electrical connection cord 9 to a power source 10 such as a car battery (possibly via the car's cigarette lighter) or a wall outlet. The switch unit 6 includes a switch 11 electrically coupled to the cord 9 , which can be switched between an “off” state in which the electrical connection to the cord 9 is opened to prevent the passage of electric power, and an “on” state in which the switch 11 permits electric power to pass therethrough. The switch 11 can be a wall switch or other conventional device. Preferably, the switch unit 6 also includes a fuse 12 (not shown in FIG. 1, but shown in FIG. 5) that is electrically coupled between the switch 11 and the timer unit 7 , and which opens the electrical connection between the switch 11 and the timer unit 7 if subjected to relatively high electric current to protect the apparatus 1 from surges in the electrical power supplied by the source. In addition, if the power source generates AC power and the motor 8 operates on DC power, the apparatus 1 can include a rectifier 61 (not shown in FIG. 1, but shown in FIG. 5 ), preferably coupled between the power source 10 and the switch 11 , that converts the AC power into DC power appropriate for the motor. In addition to or in lieu of the rectifier 61 , the apparatus 1 can include a transformer 62 (not shown in FIG. 1, but shown in FIG. 5) that is preferably electrically coupled between the power source 10 and the switch unit 6 , which converts the voltage and current level of the power source 10 into a voltage and current level appropriate for the motor 8 . If the power source 10 utilized with the apparatus 1 is a twelve-volt car battery and the motor 8 is a twelve-volt DC motor, generally, neither the rectifier 61 nor the transformer 62 are necessary and can be omitted to simplify the apparatus and its construction, as well as to reduce the cost of the apparatus 1 . Similarly, if the power source 10 is a standard wall outlet with 115-Volt AC power, a 115-Volt AC motor can be used without the rectifier 61 or the transformer 62 .
The timer unit 7 is electrically coupled to the switch unit 6 via electrical cord 71 to receive electric power therefrom when the switch 11 is turned to its “on” state and the fuse 12 is intact so that electric power can flow therethrough. The timer unit 7 serves to supply power to the motor 8 for a limited period of time as predetermined by a user of the apparatus by appropriately setting the timer with a dial or input keys, for example. In general, it is preferred that this period of time be from ten (10) to fifteen (15) minutes for relatively recently-manufactured paint balls (i.e., paint balls that are less than a few months old), but for older paint balls, the timer is preferably activated to supply electric power to the motor 8 for a time period of several hours to a few days. In addition, the timer unit 7 can also be such as to permit the power to be supplied to the motor 8 repeatedly at a predetermined time interval, as preset by the user using the apparatus 1 with the timer unit 7 . For example, the timer unit can be set to supply power to the motor unit 8 for a predetermined time period such as ten to fifteen minutes repeatedly on a daily interval basis. The timer unit 7 can be one of a variety of commercially available devices, such as those used for swimming pool pump systems, lawn watering or outdoor lighting, for example.
The timer unit 7 is electrically coupled to the motor 8 via electrical connection cord 72 . The motor 8 can be a commercially available device, such as a {fraction (1/60)}th horse power, 6-RPM, 72 inch-lb. work starting and running, 115-Volt AC motor which is widely available from a number of commercial sources. Alternatively, the motor 8 can be a 12-Volt DC motor with similar horse power and RPM characteristics as that of the AC motor described immediately above. The motor 8 is preferred to have sufficiently low power so as to stop if a user accidentally inserts a hand or arm, for example, between moving parts of the apparatus 1 , and yet should have sufficient power to move the apparatus' container 15 effectively when unobstructed. The motor 8 operates on the electric power it receives to rotate its drive shaft 16 . The motor 8 can be either directly coupled to the drive shaft 16 or can be coupled indirectly to the drive shaft 16 through gears which can be used to speed up or slow down the rotation of the drive shaft 16 relative to the rotation rate of the motor 8 .
The apparatus 1 also includes a container 15 for holding paint balls. The container 15 can be composed of a variety of materials, including metals and plastics. In this embodiment of the invented apparatus 1 , the container 15 is configured to hold a case of paint balls 100 . The case 100 is shown in broken line in FIG. 1 to represent the fact that the case of paint balls is positioned inside of the container 15 and thus would not be visible in the view of FIG. 1 . The current standard size for paint ball cases is approximately 8×12×18 inches, so the container 15 is preferably one-quarter to one inch larger in each dimension as compared to the paint ball case size. If retail paint ball packaging changes in the future, the container 15 , and the apparatus 1 in general, can be readily resized to adapt to such changes in retail paint ball packaging. The drive shaft 16 of the motor 8 extends through the side member 3 , optionally through a bearing (not shown) mounted in the side member 3 which is attached to and supports the drive shaft 16 . The drive shaft 16 engages with a side portion of the container 15 . The end of the drive shaft 16 can be welded to the container 15 , or alternatively, the drive shaft 16 can be releasably connected to the container 15 using a keyed recess 17 with a slotted, star or asterisk shape, for example, for which the end of the drive shaft is correspondingly configured so that the drive shaft can be fitted to the recess 17 to drive the container 15 to rotate. In another alternative configuration, the drive shaft 16 can be connected to the container 15 with a quick-release coupler, for example. The latter two options permit the container 15 to be removed from or coupled to the drive shaft 16 as desired, and can also permit the use of containers 15 with different sizes. On the side portion of the container 15 opposite the side portion that engages with the drive shaft 16 , the container 15 engages with a support shaft 18 of the apparatus 1 . The support shaft 18 is supported by the side member 4 either in direct contact therewith or through the use of a bearing 19 mounted in the side member 4 through which the support member 18 extends and to which the support member is fixed by welding or adhesive, for example. Similar to the drive shaft 16 , the support shaft 18 can either be attached to the side of the container 15 , or engaged therewith with a key formed at the end of the support shaft 18 which engages in a correspondingly keyed recess in the side of the container 15 , or via a quick-release coupler, for example, to permit the container to be removed from the remainder of the apparatus 1 . The drive shaft 16 and the support member 18 are aligned along a common axis about which the container 15 is rotated relative to the support member 2 by the motor 8 during operation of the apparatus 1 , as shown by the direction arrows in FIG. 1 .
In this embodiment of the invented apparatus, the container 15 preferably includes two parts 20 , 21 , preferably made of rigid metal or plastic. The part 20 constitutes the front and top planar portions of the container 15 , whereas the part 21 constitutes the two opposing planar side portions, and the planar rear and bottom portions of the container 15 in the view of FIG. 1 . The container 15 also preferably includes a hinge 22 attached between the parts 20 , 21 to allow the part 20 to be rotated relative to the part 21 to open or close the container 15 . To secure the container 15 in its closed position, the container 15 includes a securing device 23 which can be any of a wide variety of devices. For example, the securing device 23 can include a wire loop pivotally mounted to a lever which in turn is pivotally mounted to the front portion of the first part 20 . The wire loop can be engaged with a protrusion of rigid material such as metal, that is mounted to the front edge of the bottom portion of the second part 21 . By turning the lever against the front portion of the first part 20 , the wire loop can be tightened about the protrusion to secure the first and second parts 20 , 21 together.
FIG. 2 shows the apparatus 1 with the container 15 in its opened position. More specifically, in FIG. 2, the securing device 23 is released and the first part 20 is rotated about hinge 22 relative to the second part 21 to the container's opened position to reveal the case of paint balls 100 held inside of the container 15 .
The apparatus 1 of FIGS. 1 and 2 can include an enclosure 24 mounted to the side member 3 , which is illustrated in broken line to indicate in this case that the enclosure is an optional feature of the invented apparatus 1 . The enclosure 24 serves to protect the switch unit 6 , the timer unit 7 and the motor 8 and can also be used to provide an attractive appearance for the apparatus 1 . The enclosure 24 substantially encloses the switch unit 6 , the timer unit 7 , and the motor 8 , but preferably defines openings to permit the switch 11 and the timer unit 7 to be accessed and operated by a user.
In operation of the apparatus 1 of FIGS. 1 and 2, a case of paint balls 100 is loaded by hand into the second part of the container 15 so that the case is positioned as shown in FIG. 2 . The timer unit 7 is set as desired by a user so that the motor will operate for a predetermined time period. Optionally, the timer unit 7 can be such as to be set by the user to switch the motor between its “on” and “off” states at predetermined regular time intervals as desired by the user, such as at daily time intervals. The first part 20 is rotated about hinge 22 to enclose the case 100 between the first and second parts 20 , 21 , and the securing device 23 is secured to hold together the first and second parts 20 , 21 in the container's closed position. The switch 11 is then turned from its “off” state to its “on” state to permit electric power to pass to the timer unit 7 to start operation of the apparatus 1 . The timer unit 7 tracks the time and supplies electric power to the motor unit 8 during the time period for which the timer unit has been set. When supplied with power from the timer unit 7 , the motor 8 rotates its drive shaft 16 to cause the container 15 and the paint balls contained therein to rotate. As the container 15 rotates, the contents of the paint balls are agitated to cause the constituents of their liquid contents to be evenly distributed therein after sufficient rotation of the container 15 . In addition, the rotation of the paint balls causes their liquid contents to push dimples outwardly relative to the center of the paint balls due to centrifugal force, to remove the dimples and restore the paint balls to the desired spherical shape. Upon expiration of the time period for which the timer unit 7 has been set, the timer unit cuts off electric power to the motor unit 8 to stop the motor from rotating the container 15 . The switch 111 can be moved from its “on” to its “off” state, the securing device 23 can be released, and the container opened to extract the case of paint balls 100 for use in paint ball guns.
The second embodiment of the invented apparatus 1 is shown in FIGS. 3 and 4. In FIG. 3, the apparatus 1 includes the switch unit 6 , the timer unit 7 , a motor 8 , electrical connection cords 9 , 71 , 72 , and optionally an enclosure 24 , as described with reference to the first embodiment of the invention. In the second embodiment of the invented apparatus 1 , the support member 2 is configured somewhat differently as compared to that of the apparatus' first embodiment. More specifically, the support member 2 includes rigid planar opposing rear and front members 30 , 31 , and a rigid planar base member 32 which extends between the rear and front members 30 , 31 . The base member 32 serves to support the apparatus 1 on a surface. The switch unit 6 , the timer unit 7 , the motor 8 and the enclosure 24 are mounted to the rear member 30 , and the drive shaft 16 of the motor preferably extends through the member 30 . The front member 31 has two wheels 33 , 34 (only wheel 33 is visible in FIG. 3) rotatably mounted thereto at spaced positions. In the second embodiment of the invented apparatus 1 , the container 15 includes a bucket 35 in which are placed paint balls 101 . The paint balls 101 are indicated in broken line to indicate that they are positioned inside of the bucket and would thus not be visible in the view of FIG. 3 . The bucket 35 includes a cylindrical side surface 36 with a bottom end closed by planar bottom surface 37 . The bucket 35 can be composed of rigid material such as plastic or metal. The bottom surface 37 defines a keyed recess 45 which corresponds to the keyed end of drive shaft 16 so that the bucket 35 will rotate about its symmetrical axis when driven by the motor 8 as shown by the direction arrows in FIG. 3 . To hold the paint balls 101 inside of the bucket 35 , the container 15 can include a lid 38 which can be force-fitted or threaded to the open end of the bucket. The bucket 35 with threaded lid 38 are commercially available from a variety of sources, such as Gamma Plastics™, Inc. of San Diego, Calif. On the interior surface of the bucket 35 , the container 15 can include one or more agitators 39 (in the example of FIG. 3 there are three) that are illustrated in broken line in FIG. 3 to indicate that they are inside of the bucket and thus could not be seen in the view of FIG. 3 . The agitators 39 are elongated members that serve to urge the paint balls 101 to move as the bucket 35 rotates when driven by the motor 8 . The agitators 39 extend along the inside of the bucket from the top to the bottom thereof. The agitators 39 also extend from the cylindrical inner surface of the bucket toward the bucket's central axis, preferably for a distance of one-quarter to a few inches. The agitators 39 are preferably made of a soft material such as foam rubber, neoprene or soft curable plastic material, to avoid damaging the paint balls 101 . The agitators 39 can be formed by molding or extruding a curable soft plastic material with a mold, die or by hand, or by cutting a larger sheet of material such as neoprene or foam rubber to size to produce the agitators. The agitators 39 can be attached to the inside surface of the bucket 35 with an adhesive, for example, or can be composed of a material which adheres to the bucket's side when cured. The agitators 39 are preferably spiral-shaped, with bottom ends positioned more forwardly with respect to the direction of rotation of the bucket 35 (see direction arrows) as compared to the top ends of the agitators. This disposition of the agitators 39 urges the paint balls 101 toward the top of the bucket 35 (i.e., to the right in FIG. 3 ). Because the wheels 33 , 34 and drive shaft 16 preferably hold the bucket 35 so that its top portion is more elevated as compared to its bottom portion, the paint balls will normally tend to roll toward the bottom of the bucket 35 (i.e., toward the left in FIG. 3 ). With their spiral configurations, the agitators 39 counteract the effects of gravity to force the paint balls to the right in FIG. 3 to more evenly distribute the paint balls along the bucket's cylindrical side surface so that the paint balls do not tend to pile up in the bottom of the bucket during operation of the apparatus. Each agitator 39 preferably extends along a portion of the circumference of the bucket's cylindrical surface that is at least approximately equal to the total circumference (i.e., 360 degrees) divided by the total number of agitators used. Thus, in the example of FIG. 4, each of the three agitators 39 extends along 120 degrees, or in other words one-third, of the total circumference of the bucket's cylindrical surface. The inside surface of the bucket 35 can be lined with soft or sponge-like sheet material 46 (shown in FIG. 4) such as neoprene or foam rubber, to cushion the paint balls 101 as the bucket 35 rotates to prevent the paint balls from being damaged.
FIG. 4 is a view of the apparatus 1 which shows the agitators 39 attached to the inside of the bucket 35 . In addition, FIG. 4 shows the wheels 33 , 34 engaging with and supporting the bucket's cylindrical surface on opposite sides thereof. The wheels 33 , 34 rotate in contact with the bucket's cylindrical surface as the motor 8 drives the bucket to rotate via the drive shaft 16 and the keyed recess 45 defined in the bucket's bottom surface. The wheels 33 , 34 are rotatably mounted to the member 31 , optionally using respective bearings 40 , 41 which extend through and are secured to the member 31 with respective bolts or the like. The wheels 33 , 34 preferably have surfaces with sufficient traction to avoid slipping in contact with the container 15 . For example, the wheels 33 , 34 can have rubber surfaces, for example, to provide ample traction with the bucket 35 .
In operation of the embodiment of the apparatus 1 shown in FIGS. 3 and 4, paint balls 101 are placed inside of the bucket 35 . The keyed recess 45 of the bucket is inserted on the drive shaft 16 , and the bucket is positioned between and in contact with the wheels 33 , 34 . The timer unit 7 is set as appropriate to operate the motor for a predetermined time period. Optionally, the timer unit 7 can also be set to operate at predetermined regular time intervals, such as on a daily basis. The switch 11 is then turned from its “off” state to its “on” state to permit electric power to pass to the timer unit 7 to start operation of the apparatus 1 . When supplied with power from the timer unit 7 during the set time period, the motor 8 rotates its drive shaft 16 to cause the bucket 35 and the paint balls therein to rotate. Preferably, the motor 8 rotates the bucket at approximately one-quarter (¼) to twenty (20) RPM, and most preferably, from six (6) to eight (8) RPM. As the bucket 35 rotates, the agitators 39 move into contact with the paint balls 101 to cause them to roll so that the contents of the paint balls are agitated and the constituent parts of the paint balls' liquid contents become more evenly distributed. In addition, the rolling of the paint balls causes the liquid contents thereof to force out dimples by pushing in a direction outwardly from the centers of the paint balls outwardly to force out the dimples. When the paint balls are desired to be extracted from the bucket 35 for use, the switch 11 can be moved from its “on” state to its “off” state and the bucket 35 can be lifted away from the drive shaft 16 and the wheels 33 , 34 and set upon its bottom surface to permit paint balls to be extracted for use in paint ball guns. Because the liquid contents of the paint balls 101 are mixed by the invented apparatus 1 so that the weight of their liquid contents is evenly distributed, and because dimples are worked out of the paint balls' shells, the paint balls will fly in a true trajectory when shot from a paint ball gun and will not tend to jam therein. Furthermore, through use of the apparatus 1 , the paint balls can be assured to be substantially spherical so that they will fly at consistent speeds from the gun to avoid chronograph fouls from guns which shoot at impermissibly high velocities, and conversely, provide the player with assurance that the paint balls will not fly too slowly so that the player has the capability to readily hit opposing players with paint balls shot from the gun.
FIG. 5 shows a block diagram of the basic elements of the invented apparatus 1 which are common to both the first embodiment of FIGS. 1 and 2, and the second embodiment of FIGS. 3 and 4. In FIG. 5, the power source 10 is electrically coupled to the switch unit 6 , and more specifically, to the switch 11 , via the connection cord 9 (the switch unit 6 is indicated in broken line to indicate that it is an optional feature of the apparatus, although its use is preferred). Optionally, if the power source 10 is an AC source and the motor operates on DC power, the rectifier 61 can be used to convert the AC power of the source 10 into DC power appropriate for the motor 8 . The rectifier 61 and the transformer 62 are indicated in broken lines in FIG. 5 to indicate that they are optional features of the invention. Also, if the motor 8 operates at a different voltage and current level than that of the power source 10 , a transformer 62 can be coupled between the source 10 and the motor 8 to convert the voltage and current level of the source 10 into voltage and current levels appropriate for the motor 8 . The switch 11 is electrically coupled to the fuse 12 which is in turn electrically coupled to the timer unit 7 via the electrical connection cord 71 . The timer unit 7 is electrically coupled to the motor 8 (the timer unit 7 is also indicated in broken line in FIG. 5 to indicate that it is an optional feature of the apparatus). The motor 8 is mechanically coupled via its drive shaft 16 to the container 15 to rotate the container when supplied with power from the switch unit 6 and the timer unit 7 .
The invented method includes a step of placing paint balls in a container, and a step of moving the container to in turn move the paint balls to agitate their liquid contents. Preferably, the moving step is performed by an apparatus which may be such as those described with reference to FIGS. 1-5. The paint balls can be placed in the container either loosely or in a case or other retail packaging used for shipment and storage of paint balls. The container can be either a rectangular box sized to receive a case of paint balls, or can be a bucket. The bucket can include at least one agitator to move the paint balls in the performance of the moving step. The moving step can be performed by rotating the container. Preferably, the paint balls are moved in the moving step for a predetermined period of time, such as ten to fifteen minutes for relatively newly-manufactured paint balls, and from several hours to a few days for older paint balls. In addition, the moving step can be performed at a regular time interval, such as on a daily basis.
The many features and advantages of the present invention are apparent from the detailed specification and thus, it is intended by the appended claims to cover all such features and advantages of the described apparatus and method which follow in the true spirit and scope of the invention. Further, since numerous modifications and changes will readily occur to those of ordinary skill in the art, it is not desired to limit the invention to the exact construction and operation illustrated and described. Accordingly, all suitable modifications and equivalents may be resorted to as falling within the spirit and scope of the invention. | The invented apparatus can be used to agitate the liquid contents of paint balls to mix and evenly distribute their liquid contents so that the paint balls will fly in a true trajectory when shot from a paint ball gun. The invented apparatus also helps to remove or prevent the formation of dimples on the outer shell of the paint balls caused by sitting for extended periods of time in storage boxes, for example. The invented apparatus can thus be used to repair defective paint balls and to extend the useful life of such paint balls. The apparatus includes a support member, a motor, and a container . The motor is mounted to the support member, and the container is supported for rotation by the support member and the motor's drive shaft. Paint balls are placed in the container which is rotated by the motor during operation of the apparatus to move the paint balls to agitate their liquid contents. The invention also includes a related method. | 8 |
CROSS REFERENCE TO RELATED APPLICATION
This is a national phase application of PCT/EP 98,/06029, filed Sep. 22, 1998.
BACKGROUND OF THE INVENTION
The present invention relates to a godet for applying a liquid to an advancing yarn wherein the yarn is advanced over the outer surface of the godet as the godet rotates about its axis and wherein the liquid is applied in measured quantities to the surface of the godet so as to be applied to the yarn.
DE 29 08 404 discloses a method and an apparatus for applying a liquid to an advancing yarn. The apparatus is formed by a driven godet, which comprises radially peripheral surface areas that can be wetted. A metering device applies the liquid for lubricating the yarn in measured quantities to the surface of the godet. The yam advances over the wetted surfaces in contact therewith and thus receives its coating of the lubricant.
This known method has the disadvantage that the liquid made available on the surface for lubricating the yam decreases as the circumferential speed of the godet increases. Thus, a slowly advancing yarn is offered a relatively large quantity of liquid and a fast advancing yarn a relatively small quantity of liquid. Consequently, fast advancing yarns at a speed greater than 3,000 m/min can be lubricated by this method only inadequately.
DE 43 33 716 discloses a method and an apparatus, wherein the godet surface comprises a groove. In this groove, a liquid for lubricating a yarn is sprayed from the outside. For the lubrication, the advancing yarn is guided over the groove of the godet. Likewise, this method shows the tendency that a small amount of liquid is offered to a relatively fast advancing yarn for its lubrication.
It is therefore the object of the invention to improve a method and an apparatus of the initially described kind, so that they ensure a uniform lubrication of a yarn regardless of its speed.
SUMMARY OF THE INVENTION
The above and other objects and advantages of the present invention are achieved by the provision of a godet which defines a cylindrical outer surface, and which includes a plurality of substantially radially oriented capillaries formed in the godet and communicating with the outer surface so as to define openings on the outer surface which are distributed circumferentially thereabout. Also, a liquid supply device is connected to the capillaries for supplying a liquid to the capillaries and thus to the openings on the outer surface.
In use, the liquid is metered onto the outer surface of the godet through the capillaries and openings, and the openings are distributed over the surface of the godet. Thus, metering of the liquid is determined by the diameters of the capillaries, the number of the capillaries, as well as the rotational speed of the godet. By merely increasing the rotational speed of the godet and, thus, the surface speed, the quantity of the liquid emerging from the capillaries increases. With that, it is possible to use the method as well as the apparatus even at higher yarn speeds of more than 3,000 m/min without subjecting the lubrication effect to a change.
To lubricate one or more yarns, it is preferred to drive the godet by a motor. However, both the method and the apparatus of the present invention also offer the possibility of constructing the godet without a drive. In this instance, the yarn or yarns drive the godet. A speed control would here be possible, for example, by means of an adjustable brake. The metering is directly determined by the yarn speed. Thus, due to the centrifugal force at high yarn speeds and, with that, at high circumferential speeds of the godet, a larger quantity of liquid is present on the surface of the godet that is contacted by the yarn.
A further advantage of the invention lies in that the liquid emerging from the surface distributes very evenly over the surface. This permits metering the liquid that is applied to the yarn.
Likewise, the path of the advancing yarn never dries, since the liquid is constantly supplied to the yarn even from the bottom.
The method will be especially advantageous and efficient, when the liquid is supplied to the capillaries inside the godet. The liquid is guided without losses to the surface of the godet. The transfer into the capillaries occurs alone due to the centrifugal forces.
The capillaries extend in the surface areas that serve to lubricate the yarn. However, it will be especially advantageous, when the pore-sized openings of the capillaries are evenly distributed over the entire surface on the circumference of the godet. With that, it is possible to realize a very uniform lubrication in that the yarn loops about the godet several times. In particular, in the case of low yarn speeds, it will be possible to lubricate therewith several, parallel guided yarns at the same time. To this end, the yarns advance over the godet parallel with a multiple looping.
The variant of the method, wherein the capillaries are formed in a sleeve that is slipped over the godet casing distinguishes itself in particular in that a varied metering is to be realized in a simple manner irrespective of the rotational speed of the godet. In this connection, a sleeve slipped over the godet casing may be replaced with a second sleeve having differently configured capillaries.
To obtain a great evenness of the capillaries, it will be especially advantageous to make the sleeve of a sintered material.
To lubricate several yarns evenly with one godet, the variant of the method is especially advantageous, wherein the yarn advances with a partial looping on the godet circumference. To this end, in one embodiment of the apparatus according to the invention the pore-sized openings of the capillaries are evenly arranged within a plurality of parallel juxtaposed, radially peripheral surface areas of the godet casing or sleeve. Each of the surface areas forms a path for wetting a yarn.
In a particularly advantageous embodiment of the apparatus according to the invention, the liquid supply to the capillaries in the sleeve proceeds through a plurality of grooves arranged in the godet surface that is covered by the sleeve. In this connection, the grooves may be formed in the godet surface radially, axially or spirally. The grooves connect to the liquid supplying device, so that the liquid required for lubricating the yarn is continuously present within the groove.
The diameters of the capillaries, the number of capillaries, as well as the rotational speed of the godet determine the amount of liquid available on the surface for lubricating the yarn. The diameter of the capillaries that is selected as a function of the yarn denier is preferably in a range from 10 μm to 1,000 μm. In this connection, a number of capillaries are selected that covers from minimally 2% to maximally 75% of the surface.
BRIEF DESCRIPTION OF THE DRAWINGS
Some of the objects and advantages of the present invention having been stated, others will appear as the description proceeds, when considered in conjunction with the accompanying drawings, in which
FIG. 1 shows an apparatus of the present invention for applying a liquid to a plurality of advancing yarns;
FIG. 2 is a schematic, cross sectional view of the casing of the godet of FIG. 1;
FIG. 3 shows an apparatus of the present invention for lubricating an advancing yarn; and
FIG. 4 is a schematic, cross sectional view of the casing of the godet of FIG. 3 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 illustrates a first embodiment of an apparatus for applying a liquid to a plurality of advancing yarns. The apparatus consists of a godet 2 that connects to a drive shaft 4 . A godet drive 3 drives the shaft 4 in such a manner that the godet surface moves in the direction of the advancing yarn, as is indicated by an arrow. A sleeve 10 is securely slipped over the circumference of godet 2 . The sleeve 10 comprises a plurality of parallel juxtaposed, radially peripheral surface areas 5 . The surfaces 5 contain a plurality of substantially evenly distributed, pore-sized openings 8 , which are formed by a corresponding number of capillaries 6 that extend substantially radially into the sleeve 10 .
The godet 2 connects to a liquid supplying device 9 . FIG. 2 is a schematic, cross sectional view of the godet of FIG. 1 . The liquid supplying device 9 constructed as a tube extends into an axially directed annular groove 13 that is formed in godet casing 7 , and which is radially offset from the central axis of the godet. The annular groove 13 is arranged for rotation in godet casing 7 . The liquid supplying device comprises an outlet 14 at the end of the tube portion that extends into the annular groove 13 . The outlet 14 is arranged in the vicinity of the internal end of annular groove 13 . At the internal end of the annular groove 13 inside the godet casing 7 , a plurality of radial bores 12 arranged in a normal plane are provided. The bores 12 connect the annular groove 13 to a plurality of grooves 11 arranged in the surface of godet casing 7 . The sleeve 10 covers the grooves 11 . A plurality of capillaries 6 extend in the radial direction through the sleeve 10 . The capillaries 6 represent a connection between the grooves 11 and the surface 5 of sleeve 10 . Yarns 1 contact the surface 5 .
To lubricate yarns 1 , the godet is driven by godet drive 3 . In this connection, it is preferred to adjust the surface speed such that it is equal to the speed of the advancing yarn. However, it is also possible to generate a relative speed between the yarn 1 and the surface 5 . At the same time, the annular groove 13 receives via liquid supplying device 9 the liquid that is required for lubricating the yarn. From the annular groove 13 , the liquid flows due to the centrifugal force through bores 12 to the grooves 11 . Subsequently, the liquid enters from grooves 11 into the capillaries 6 of sleeve 10 , and reaches through capillaries 6 the surface 5 . On the surface 5 , the liquid is picked up by the yarn 1 respectively advancing thereover. Besides the rotational speed of the godet, the amount of liquid emerging from the surface 5 is dependent on the number of capillaries as well as their size.
In the apparatus shown in FIGS. 1 and 2, the sleeve 10 is exchangeable. By exchanging sleeves 10 with respectively differently shaped capillaries, it is possible to vary the metering of the liquid.
The surface areas contacted by the yarn have a roughness from Rz 2.4 to Rz 10, so that even higher loopings are possible for applying the liquid.
FIG. 3 shows an apparatus, wherein a yarn 1 is lubricated by looping several times about a godet 2 . In its construction, the apparatus of FIG. 3 is similar to that of FIG. 1 . To this extent, the description of FIGS. 1 and 2 is herewith incorporated by reference.
Unlike the embodiment of FIG. 1, FIG. 3 shows a godet 2 , wherein the pore-sized openings 8 of the capillaries 6 are evenly distributed over the entire surface 5 of godet casing 7 . As shown in FIG. 4, the capillaries 6 are directly provided in the godet casing 7 . In this embodiment, the capillaries 6 terminate in the annular groove 13 within godet casing 7 . The annular groove 13 in godet casing 7 connects again to the liquid supplying device 9 . Thus, the liquid arrives from the annular groove 13 through the capillaries 6 at the godet surface 5 . The godet surface 5 is therefore evenly wetted with the liquid over the entire area, thereby permitting a uniform lubrication of yarn 1 .
A sintered material may advantageously produce the capillaries in sleeve 10 as well as in godet casing 7 . However, it is also possible to use other porous, permeable materials for forming the capillaries in the godet casing.
A further possibility consists in working capillaries as bores into a metallic surface, for example, by laser beams. | A device and method for applying a liquid to at least one advancing yarn which is guided over a surface of a driven godet in contact therewith. A liquid is supplied through a plurality of capillaries to the surface. To this end, the pore-sized openings of the capillaries are evenly distributed on the godet surface being wetted. | 3 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims the priority benefit under 35 U.S.C. §119(e) of U.S. Provisional Application No. 61/428,653, filed Dec. 30, 2010; U.S. Provisional Application No. 61/493,447, filed Jun. 4, 2011; U.S. Provisional Application No. 61/550,889, filed Oct. 24, 2011; and U.S. Provisional Application No. 61/556,142, filed Nov. 4, 2011, the entire contents of which are hereby incorporated by reference and should be considered a part of this specification.
BACKGROUND OF THE INVENTION
1. Field of the Invention
In general, the disclosure relates to methods and apparatuses for filtering blood. The filtration systems can be catheter-based for insertion into a patient's vascular system.
2. Description of the Related Art
Thromboembolic disorders, such as stroke, pulmonary embolism, peripheral thrombosis, atherosclerosis, and the like, affect many people. These disorders are a major cause of morbidity and mortality in the United States and throughout the world. Thromboembolic events are characterized by an occlusion of a blood vessel. The occlusion can be caused by a clot which is viscoelastic (jelly-like) and is comprised of platelets, fibrinogen, and other clotting proteins.
Percutaneous aortic valve replacement has been in development for some time now and stroke rates related to this procedure are between four and twenty percent. During catheter delivery and valve implantation plaque or other material may be dislodged from the vasculature and may travel through the carotid circulation and into the brain. When an artery is occluded by a clot or other embolic material, tissue ischemia (lack of oxygen and nutrients) develops. The ischemia will progress to tissue infarction (cell death) if the occlusion persists. Infarction does not develop or is greatly limited if the flow of blood is reestablished rapidly. Failure to reestablish blood-flow can lead to the loss of limb, angina pectoris, myocardial infarction, stroke, or even death.
Occlusion of the venous circulation by thrombi leads to blood stasis which can cause numerous problems. The majority of pulmonary embolisms are caused by emboli that originate in the peripheral venous system. Reestablishing blood flow and removal of the thrombus is highly desirable.
Techniques exist to reestablish blood flow in an occluded vessel. One common surgical technique, an embolectomy, involves incising a blood vessel and introducing a balloon-tipped device (such as a Fogarty catheter) to the location of the occlusion. The balloon is then inflated at a point beyond the clot and used to translate the obstructing material back to the point of incision. The obstructing material is then removed by the surgeon. While such surgical techniques have been useful, exposing a patient to surgery may be traumatic and is best avoided when possible. Additionally, the use of a Fogarty catheter may be problematic due to the possible risk of damaging the interior lining of the vessel as the catheter is being withdrawn.
A common percutaneous technique is referred to as balloon angioplasty where a balloon-tipped catheter is introduced into a blood vessel, typically through an introducing catheter. The balloon-tipped catheter is then advanced to the point of the occlusion and inflated in order to dilate the stenosis. Balloon angioplasty is appropriate for treating vessel stenosis but is generally not effective for treating acute thromboembolisms.
Another percutaneous technique is to place a microcatheter near the clot and infuse Streptokinase, Urokinase, or other thrombolytic agents to dissolve the clot. Unfortunately, thrombolysis typically takes hours or days to be successful. Additionally, thrombolytic agents can cause hemorrhage and in many patients the agents cannot be used at all.
Another problematic area is the removal of foreign bodies. Foreign bodies introduced into the circulation can be fragments of catheters, pace-maker electrodes, guide wires, and erroneously placed embolic material such as thrombogenic coils. Retrieval devices exist for the removal of foreign bodies, some of which form a loop that can ensnare the foreign material by decreasing the size of the diameter of the loop around the foreign body. The use of such removal devices can be difficult and sometimes unsuccessful.
Moreover, systems heretofore disclosed in the art are generally limited by size compatibility and the increase in vessel size as the emboli is drawn out from the distal vascular occlusion location to a more proximal location near the heart. If the embolectomy device is too large for the vessel it will not deploy correctly to capture the clot or foreign body, and if too small in diameter it cannot capture clots or foreign bodies across the entire cross section of the blood vessel. Additionally, if the embolectomy device is too small in retaining volume then as the device is retracted the excess material being removed can spill out and be carried by flow back to occlude another vessel downstream.
Various thrombectomy and foreign matter removal devices have been disclosed in the art. Such devices, however, have been found to have structures which are either highly complex or lacking in sufficient retaining structure. Disadvantages associated with the devices having highly complex structure include difficulty in manufacturability as well as difficulty in use in conjunction with microcatheters. Recent developments in the removal device art features umbrella filter devices having self folding capabilities. Typically, these filters fold into a pleated condition, where the pleats extend radially and can obstruct retraction of the device into the microcatheter sheathing.
Extraction systems are needed that can be easily and controllably deployed into and retracted from the circulatory system for the effective removal of clots and foreign bodies. There is also a need for systems that can be used as temporary arterial or venous filters to capture and remove thromboembolic generated during endovascular procedures. The systems should also be able to be properly positioned in the desired location. Additionally, due to difficult-to-access anatomy such as the cerebral vasculature and the neurovasculature, the systems should have a small collapsed profile.
The risk of dislodging foreign bodies is also prevalent in certain surgical procedures. It is therefore further desirable that such emboli capture and removal apparatuses are similarly useful with surgical procedures such as, without limitation, cardiac valve replacement, cardiac bypass grafting, cardiac reduction, or aortic replacement.
SUMMARY OF THE INVENTION
One aspect of the disclosure is a catheter-based endovascular system and method of use for filtering blood that captures and removes particles caused as a result of a surgical or endovascular procedures. The method and system include a first filter placed in a first vessel within the patient's vascular system and a second filter placed in a second vessel within the patient's vascular system. In this manner, the level of particulate protection is thereby increased.
One aspect of the disclosure is an endovascular filtration system and method of filtering blood that protects the cerebral vasculature from embolisms instigated or foreign bodies dislodged during a surgical procedure. In this aspect, the catheter-based filtration system is disposed at a location in the patient's arterial system between the site of the surgical procedure and the cerebral vasculature. The catheter-based filtration system is inserted and deployed at the site to capture embolisms and other foreign bodies and prevent their travel to the patient's cerebral vasculature so as to avoid or minimize thromboembolic disorders such as a stroke.
One aspect of the disclosure is an endovascular filtration system and method of filtering blood that provides embolic protection to the cerebral vasculature during a cardiac or cardiothoracic surgical procedure. According to this aspect, the filtration system is a catheter-based system provided with at least a first filter and a second filter. The first filter is positioned within the brachiocephalic artery, between the aorta and the right common carotid artery, with the second filter being positioned within the left common carotid artery.
One aspect of the disclosure is a catheter-based endovascular filtration system including a first filter and a second filter, wherein the system is inserted into the patient's right brachial or right radial artery. The system is then advanced through the patient's right subclavian artery and into the brachiocephalic artery. Alternately, the system may be inserted directly into the right subclavian artery. At a position within the brachiocephalic trunk between the aorta and the right common carotid artery, the catheter-based system is manipulated to deploy the first filter. The second filter is then advanced through or adjacent to the deployed first filter into the aorta and then into the left common carotid artery. Once in position within the left common carotid artery the catheter-based system is further actuated to deploy the second filter. After the surgical procedure is completed, the second filter and the first filter are, respectively, collapsed and withdrawn from the arteries and the catheter-based filtration system is removed from the patient's vasculature. In an alternate embodiment, either or both the first and second filters may be detached from the filtration system and left inside the patient for a therapeutic period of time.
One aspect of the disclosure is a catheter-based filtration system comprising a handle, a first sheath, a first filter, a second sheath and a second filter. The first and second sheaths are independently actuatable. The handle can be a single or multiple section handle. The first sheath is translatable relative to the first filter to enact deployment of the first filter in a first vessel. The second sheath is articulatable from a first configuration to one or more other configurations. The extent of articulation applied to the second sheath is determined by the anatomy of a second vessel to which access is to be gained. The second filter is advanced through the articulated second sheath and into the vessel accessed by the second sheath and, thereafter, deployed in the second vessel. Actuation of the first sheath relative to the first filter and articulation of the second filter is provided via the handle. In some embodiments, the handle includes a locking mechanism configured to lock the first sheath relative to the second sheath. In certain embodiments, the handle also includes a distal flush port.
In some aspects of the disclosure, the second filter is carried on a guiding member having a guidewire lumen extending therethrough. In certain aspects, the guiding member is a catheter shaft. A guiding member having a guidewire lumen allows the user to precisely deliver the second filter by advancing the filter system over the guidewire. The guiding member can be configured to have increased column strength to aid advancement of the second filter. In some aspects, the guiding member includes a flexible portion to better position the second filter within the vessel.
In some aspects the first sheath is a proximal sheath, the first filter is a proximal filter, the second sheath is a distal sheath, and the second filter is a distal filter. The proximal sheath is provided with a proximal hub housed within and in sliding engagement with the handle. Movement of the proximal hub causes translation of the proximal sheath relative to the proximal filter. The distal sheath includes a distal shaft section and a distal articulatable sheath section. A wire is provided from the handle to the distal articulatable sheath section. Manipulation of the handle places tension on the wire causing the distal articulatable sheath section to articulate from a first configuration to one or more other configurations. The articulatable distal sheath is capable of rotation, translation, and deflection (both in a single plane and both partially in a first plane and partially in a second, different plane). In some embodiments, the handle includes a locking mechanism to prevent the articulatable distal sheath from deviating from a desired configuration. In certain embodiments, the locking mechanism may lock automatically when the operator actuates a control or releases the handle.
In some aspects the proximal filter and the distal filter are both self-expanding. The proximal filter and the distal filter both may comprise an oblique truncated cone shape. Movement of the proximal sheath relative to the proximal filter causes the proximal filter to expand and deploy against the inside wall of a first vessel. The distal filter is then advanced through or adjacent to the distal shaft and distal articulatable sheath into expanding engagement against the inner wall of a second vessel. In some embodiments, a tethering member extends from the proximal sheath to the proximal filter to help draw the proximal filter opening toward the first vessel wall.
Another aspect of the disclosure is a single filter embolic protection device comprising a single filter device comprising a sheath, a filter shaft, and a filter assembly. In some aspects, the filter assembly is designed to accommodate a catheter-based device passing between the filter and the vessel wall. In certain embodiments, the filter assembly may include a channel, a gap, or an inflatable annulus. The filter assembly may also include one or more filter lobes. In another embodiment, the filter assembly may resemble an umbrella having a plurality of tines and a filter element connecting each tine. The filter assembly may alternatively include a plurality of overlapping filter portions, wherein a catheter may pass between a first filter portion and a second filter portion of the filter assembly.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates an exemplary prior art catheter being advanced through a portion of a subject's vasculature.
FIGS. 1A-1D illustrate an exemplary dual filter system.
FIGS. 1E and 1F illustrate exemplary proximal filters.
FIGS. 2A-2D illustrate an exemplary method of delivering and deploying a dual filter system
FIGS. 3-5 illustrate a portion of an exemplary delivery procedure for positioning a blood filter.
FIGS. 6A and 6B illustrate an exemplary embodiment of an articulating distal sheath.
FIGS. 7A-7C illustrate a portion of an exemplary filter system.
FIGS. 8A-8C illustrate an exemplary pull wire.
FIGS. 9A-9C show an exemplary embodiment of a distal sheath with slots formed therein.
FIGS. 9D-9E show an exemplary embodiment of a distal sheath capable of deflecting in multiple directions.
FIGS. 9F and 9G illustrate exemplary guidewire lumen locations in the distal sheath.
FIGS. 10A and 10B illustrate a portion of exemplary distal sheath adapted to be multi-directional.
FIGS. 11A-11E illustrate merely exemplary anatomical variations that can exist.
FIGS. 12A and 12B illustrate an exemplary curvature of a distal sheath to help position the distal filter properly in the left common carotid artery.
FIGS. 13A and 13B illustrate alternative distal sheath and distal shaft portions of an exemplary filter system.
FIG. 14 illustrates a portion of an exemplary system including a distal shaft and a distal sheath.
FIGS. 15A-15D illustrate alternative embodiments of the coupling of the distal shaft and distal sheath.
FIG. 16 illustrates an exemplary embodiment of a filter system in which the distal sheath is biased to a curved configuration.
FIG. 17 illustrates a portion of an alternative filter system.
FIGS. 18A and 18B illustrate an exemplary proximal filter.
FIGS. 19A-19C , 20 A- 20 B, 21 , 22 A-B illustrate exemplary proximal filters.
FIGS. 23A-23F illustrate exemplary distal filters.
FIGS. 24A-24C illustrate exemplary embodiments in which the system includes at least one distal filter positioning, or stabilizing, anchor.
FIGS. 25A-25D illustrate an exemplary embodiment of coupling a distal filter to a docking wire inside of the subject.
FIGS. 26A-26G illustrate an exemplary method of preparing an exemplary distal filter assembly for use.
FIGS. 27A and 27B illustrate an exemplary embodiment in which a guiding member, secured to a distal filter before introduction into the subject is loaded into an articulatable distal sheath.
FIGS. 28A-28E illustrate an exemplary distal filter assembly in collapsed and expanded configurations.
FIGS. 29A-29E illustrate a portion of an exemplary filter system with a lower delivery and insertion profile.
FIGS. 30A and 30B illustrate a portion of an exemplary filter system.
FIGS. 31A-31C illustrate an exemplary over-the-wire routing system that includes a separate distal port for a dedicated guidewire.
FIGS. 32A-32E illustrate an exemplary routing system which includes a rapid-exchange guidewire delivery.
FIGS. 33A-D illustrates a filter system which includes a tubular core member.
FIGS. 34A-C illustrate a filter system with a flexible coupler.
FIGS. 35A-E illustrate alternate designs for a flexible coupler.
FIGS. 36A-C illustrate a method of using a tethering member.
FIGS. 36D-E illustrate attachment points for a tethering member.
FIGS. 37A-D illustrate multiple embodiments for a tethering member.
FIGS. 38A-D illustrate multiple embodiments for an aortic filter designed to form a seal around a catheter.
FIGS. 39A-C illustrate an aortic filter system having multiple aortic filters.
FIGS. 40A-B exemplify multiple embodiments for an aortic filter.
FIGS. 41A-B illustrate an aortic filter having an inflatable annulus.
FIG. 42 illustrates a distal portion of an exemplary filter system.
FIGS. 43-46 illustrate exemplary control handles of the blood filter systems.
FIGS. 47A-H illustrate cross-sectional portions of an exemplary control handle.
FIG. 48 depicts an alternative control handle with a rotary tip deflection control.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Although certain preferred embodiments and examples are disclosed below, inventive subject matter extends beyond the specifically disclosed embodiments to other alternative embodiments and/or uses, and to modifications and equivalents thereof. Thus, the scope of the claims appended hereto is not limited by any of the particular embodiments described below. For example, in any method or process disclosed herein, the acts or operations of the method or process can be performed in any suitable sequence and are not necessarily limited to any particular disclosed sequence. Various operations can be described as multiple discrete operations in turn, in a manner that can be helpful in understanding certain embodiments; however, the order of description should not be construed to imply that these operations are order dependent. Additionally, the structures described herein can be embodied as integrated components or as separate components. For purposes of comparing various embodiments, certain aspects and advantages of these embodiments are described. Not necessarily all such aspects or advantages are achieved by any particular embodiment. Thus, for example, various embodiments can be carried out in a manner that achieves or optimizes one advantage or group of advantages as taught herein without necessarily achieving other aspects or advantages as can also be taught or suggested herein.
The disclosure relates generally to intravascular blood filters used to capture foreign particles. In some embodiments the blood filter is a dual-filter system to trap foreign bodies to prevent them from traveling into the subject's right and left common carotid arteries, while in other embodiments, the blood filter is a single filter system. The filter systems described herein can, however, be used to trap particles in other blood vessels within a subject, and they can also be used outside of the vasculature. The systems described herein are generally adapted to be delivered percutaneously to a target location within a subject, but they can be delivered in any suitable way, and need not be limited to minimally-invasive procedures.
Filter systems in accordance with the present invention can be utilized to reduce the occurrence of emboli entering the cerebral circulation as a consequence of any of a variety of intravascular interventions, including, but not limited to, transcatheter aortic-valve implantation (TAVI), surgical valve repair or replacement, atrial fibrillation ablation, cardiac bypass surgery, or transthoracic graft placement around the aortic arch. For example, the present filter or filters may be placed as described elsewhere herein prior to a minimally invasive or open surgical repair or replacement of a heart valve, such as the mitral or aortic valve. The filter system may alternatively be placed prior to cardiac ablation such as ablation of the pulmonary vein to treat atrial fibrillation. Ablation may be accomplished using any of a variety of energy modalities, such as RF energy, cryo, microwave or ultrasound, delivered via a catheter having a distal end positioned within the heart. The present filter systems may alternatively be placed prior to cardiac bypass surgery, or prior to transthoracic graft placement around the aortic arch, or any of a variety of other surgeries or interventions that are accompanied by a risk of cerebral embolization.
In one application, the filter systems described herein are used to protect the cerebral vasculature against embolisms and other foreign bodies entering the bloodstream during a cardiac valve replacement or repair procedure. To protect both the right common carotid artery and the left common carotid artery during such procedures, the system described herein enters the aorta from the brachiocephalic artery. Once in the aortic space, there is a need to immediately navigate a 180 degree turn into the left common carotid artery. In gaining entry into the aorta from the brachiocephalic artery, use of prior art catheter devices 1 will tend to hug the outer edge of the vessel 2 , as shown in FIG. 1 . To then gain access to the left common carotid artery 3 with such prior art devices can be a difficult maneuver due to the close proximity of the two vessels which may parallel one another, often within 1 cm of separation, as shown in, for example, FIGS. 1-5 . This sharp turn requires a very small radius and may tend to kink the catheter reducing or eliminating a through lumen to advance accessories such as guidewires, filters, stents, and other interventional tools. The catheter-based filter systems described herein can traverse this rather abrupt essentially 180 degree turn to thereby deploy filters to protect both the right and left common carotid arteries.
FIGS. 1A-1C illustrate an exemplary filter system having control handle portion 5 and filter system 10 . In some embodiments, control handle portion 5 may include a distal flush port 4 . Filter system 10 includes proximal sheath 12 , proximal shaft 14 coupled to expandable proximal filter 16 , distal shaft 18 coupled to distal articulatable sheath 20 , distal filter 22 , and guiding member 24 . FIG. 1B illustrates proximal filter 16 and distal filter 22 in expanded configurations. FIG. 1C illustrates the system in a delivery configuration, in which proximal filter 16 (not seen in FIG. 1C ) is in a collapsed configuration constrained within proximal sheath 12 , while distal filter 22 is in a collapsed configuration constrained within distal articulatable sheath 20 .
FIG. 1D is a sectional view of partial system 10 from FIG. 1C . Proximal shaft 14 is co-axial with proximal sheath 12 , and proximal region 26 of proximal filter 16 is secured to proximal shaft 14 . In its collapsed configuration, proximal filter 16 is disposed within proximal sheath 12 and is disposed distally relative to proximal shaft 14 . Proximal sheath 12 is axially (distally and proximally) movable relative to proximal shaft 14 and proximal filter 16 . System 10 also includes distal sheath 20 secured to a distal region of distal shaft 18 . Distal shaft 18 is co-axial with proximal shaft 14 and proximal sheath 12 . Distal sheath 20 and distal shaft 18 , secured to one another, are axially movable relative to proximal sheath 12 , proximal shaft 14 and proximal filter 16 . System 10 also includes distal filter 22 carried by guiding member 24 . In FIG. 1D distal filter 22 is in a collapsed configuration within distal sheath 22 . Guiding member 24 is coaxial with distal sheath 20 and distal shaft 18 as well as proximal sheath 12 and proximal shaft 14 . Guiding member 24 is axially movable relative to distal sheath 20 and distal shaft 18 as well as proximal sheath 12 and proximal shaft 14 . Proximal sheath 12 , distal sheath 20 , and guiding member 24 are each adapted to be independently moved axially relative to one other. That is, proximal sheath 12 , distal sheath 20 , and guiding member 24 are adapted for independent axial translation relative to each of the other two components.
In the embodiments in FIGS. 1A-1F , proximal filter 16 includes support element or frame 15 and filter element 17 , while distal filter 22 includes support element 21 and filter element 23 . The support elements generally provide expansion support to the filter elements in their respective expanded configurations, while the filter elements are adapted to filter fluid, such as blood, and trap particles flowing therethrough. The expansion supports are adapted to engage the wall of the lumen in which they are expanded. The filter elements have pores therein that are sized to allow the blood to flow therethrough, but are small enough to prevent unwanted foreign particles from passing therethrough. The foreign particles are therefore trapped by and within the filter elements.
In one embodiment, filter element 17 is formed of a polyurethane film mounted to frame 15 , as shown in FIGS. 1E and 1F . Film element 17 can measure about 0.0001 inches to about 0.1 inches in thickness. In some embodiments, the film thickness measures between 0.005 and 0.05, or between 0.015 and 0.025. In some situations, it may be desirable to have a filter with a thickness less than 0.0001 or greater than 0.1 inches. Other polymers may also be used to form the filter element, in the form of a perforated sheet or woven or braided membranes. Thin membranes or woven filament filter elements may alternatively comprise metal or metal alloys, such as nitinol, stainless steel, etc.
Filter element 17 has through holes 27 to allow fluid to pass and will resist the passage of the embolic material within the fluid. These holes can be circular, square, triangular or other geometric shapes. In the embodiment as shown in FIG. 1E , an equilateral triangular shape would restrict a part larger than an inscribed circle but have an area for fluid flow nearly twice as large making the shape more efficient in filtration verses fluid volume. It is understood that similar shapes such as squares and slots would provide a similar geometric advantage. In certain embodiments, the filter holes are laser drilled into the filter membrane, but other methods can be used to achieve a similar result. In some embodiments filter holes 27 are between about 1 micron and 1000 microns (1 mm). In certain embodiments, the hole size is between 1 micron and 500 microns. In other embodiments, the hole size is between 50 microns and 150 microns. However, the hole size can be larger, depending on the location of the filter within the subject and the type of particulate sought to be trapped in the filter.
In several embodiments, frame element 15 can be constructed of a shape memory material such as Nitinol, or other materials such as stainless steel or cobalt super alloy (MP35N for example) that have suitable material properties. Frame element 15 could take the form of a round wire or could also be of a rectangular or elliptical shape to preserve a smaller delivery profile. In one such embodiment, frame element 15 comprises Nitinol wire where the hoop is created from a straight piece of wire and shape set into a frame where two straight legs run longitudinally along the delivery system and create a circular distal portion onto which the filter film will be mounted. The circular or loop portion may include a radiopaque marker such as a small coil of gold, platinum iridium, or other radiopaque marker for visualization under fluoroscopy. In other embodiments, the frame element may not comprise a hoop, but include a spinal element disposed across a longitudinal length of the filter element. In still other embodiments, the filter element may not include a frame element.
The shape of the filter opening or frame elements 15 , 17 may take a circular shape when viewed axially or other shape that apposes the vessel wall. In some embodiments, such as those illustrated in FIGS. 1E , 1 F and 25 D, the shape of frame element 15 and filter element 17 are of an oblique truncated cone having a non-uniform or unequal length around and along the length of the conical filter 16 . In such a configuration, much like a windsock, the filter 16 would have a larger opening (upstream) diameter and a reduced ending (downstream) diameter. The unconstrained, fully expanded filter diameter can measure between 3 mm and 30 mm, but in some embodiments, the diameter may be less than 3 mm or greater than 30 mm. In some embodiments, the diameter may range between 10-25 mm or between 15-20 mm. The length of the filter may range between 10 mm and 50 mm, but the length of the filter may be less than 10 mm or greater than 50 mm. In some embodiments, the length may range between 10 mm and 30 mm or between 30 mm and 50 mm. In one embodiment, the diameter of the filter opening could measure about 15-20 mm in diameter and have a length of about 30-50 mm. A selection of different filter sizes would allow treatment of a selection of patients having different vessel sizes.
In some embodiments the material of the filter element is a smooth and/or textured surface that is folded or contracted into a small delivery catheter by means of tension or compression into a lumen. A reinforcement fabric 29 , as shown in FIG. 1F , may be added to or embedded in the filter to accommodate stresses placed on the filter material by means of the tension or compression applied. This will also reduce the stretching that may occur during delivery and retraction of filter element 17 . This reinforcement material 29 could be a polymer or metallic weave to add additional localized strength. This material could be imbedded into the polyurethane film to reduce its thickness. In one particular embodiment, this imbedded material could be a polyester weave mounted to a portion of the filter near the longitudinal frame elements where the tensile forces act upon the frame and filter material to expose and retract the filter from its delivery system. In some embodiments, the film measures between 0.0005 and 0.05, between 0.0025 and 0.025, or between 0.0015 and 0.0025 inches thick. In certain embodiments, the thickness is between 0.015 and 0.025 inches. In some situations, it may be desirable to have a filter with a thickness less than 0.0001 or greater than 0.1 inches. In some embodiments, the reinforcement fabric has a pore size between about 1 micron and about 1000 microns. In certain embodiments, the pore size is between about 50 microns and about 150 microns. While such an embodiment of the filter elements has been described for convenience with reference to proximal filter element 17 , it is understood that distal filter element 23 could similarly take such form or forms.
As shown in FIG. 1B , proximal filter 16 has a generally distally-facing opening 13 , and distal filter 22 has a generally proximally-facing opening 19 . The filters can be thought of as facing opposite directions. As described in more detail below, the distal sheath is adapted to be steered, or bent, relative to the proximal sheath and the proximal filter. As the distal sheath is steered, the relative directions in which the openings face will be adjusted. Regardless of the degree to which the distal sheath is steered, the filters are still considered to having openings facing opposite directions. For example, the distal sheath could be steered to have a 180 degree bend, in which case the filters would have openings facing in substantially the same direction. The directions of the filter openings are therefore described if the system were to assume a substantially straightened configuration, an example of which is shown in FIG. 1B . Proximal filter element 17 tapers down in the proximal direction from support element 15 , while distal filter element 23 tapers down in the distal direction from support element 21 . A fluid, such as blood, flows through the opening and passes through the pores in the filter elements, while the filter elements are adapted to trap foreign particles therein and prevent their passage to a location downstream to the filters.
In several embodiments, the filters are secured to separate system components. In the embodiment in FIGS. 1A-1D , for example, proximal filter 16 is secured to proximal shaft 14 , while distal filter 22 is secured to guiding member 24 . In FIGS. 1A-1D , the filters are secured to independently-actuatable components. This allows the filters to be independently positioned and controlled. Additionally, the filters are collapsed within two different tubular members in their collapsed configurations. In the embodiment in FIGS. 1A-1D , for example, proximal filter 16 is collapsed within proximal sheath 12 , while distal filter 22 is collapsed within distal sheath 20 . In the system's delivery configuration, the filters are axially-spaced from one another; however, in an alternative embodiment, the filters may be positioned such that a first filter is located within a second filter. For example, in FIG. 1D , distal filter 22 is distally-spaced relative to proximal filter 16 .
In some embodiments the distal sheath and the proximal sheath have substantially the same outer diameter (see, e.g., FIGS. 1C and 1D ). When the filters are collapsed within the sheaths, the sheath portion of the system therefore has a substantially constant outer diameter, which can ease the delivery of the system through the patient's body and increase the safety of the delivery. In FIG. 1D , distal and proximal sheaths 20 and 12 have substantially the same outer diameter, both of which have larger outer diameters than the proximal shaft 14 . Proximal shaft 14 has a larger outer diameter than distal shaft 18 , wherein distal shaft 18 is disposed within proximal shaft 14 . Guiding member 24 has a smaller diameter than distal shaft 18 . In some embodiments the proximal and distal sheaths have an outer diameter between 3 French (F) and 14 F. In certain embodiments, the outer diameter is between 4 F and 8 F. In still other embodiments, the outer diameter is between 4 F and 6 F. In some embodiments the sheaths have different outer diameters. For example, the proximal sheath can have a size of 6 F, while the distal sheath has a size of 5 F. In an alternate embodiment the proximal sheath is 5 F and the distal sheath is 4 F. A distal sheath with a smaller outer diameter than the proximal sheath reduces the delivery profile of the system and can ease delivery. In some methods of use, the filter system is advanced into the subject through an incision made in the subject's right radial artery. In a variety of medical procedures a medical instrument is advanced through a subject's femoral artery, which is larger than the right radial artery. A delivery catheter used in femoral artery access procedures has a larger outer diameter than would be allowed in a filter system advanced through a radial artery. Additionally, in some uses the filter system is advanced from the right radial artery into the aorta via the brachiocephalic trunk. The radial artery has the smallest diameter of the vessels through which the system is advanced. The radial artery therefore limits the size of the system that can be advanced into the subject when the radial artery is the access point. The outer diameters of the systems described herein, when advanced into the subject via a radial artery, are therefore smaller than the outer diameters of the guiding catheters (or sheaths) typically used when access is gained via a femoral artery.
FIG. 6A illustrates a portion of a filter delivery system in a delivery configuration. The system's delivery configuration generally refers to the configuration when both filters are in collapsed configurations within the system. FIG. 6B illustrates that the distal articulating sheath is independently movable with 3 degrees of freedom relative to the proximal sheath and proximal filter. In FIG. 6A , proximal sheath 60 and distal sheath 62 are coupled together at coupling 61 . Coupling 61 can be a variety of mechanisms to couple proximal sheath 60 to distal sheath 62 . For example, coupling 61 can be an interference fit, a friction fit, a spline fitting, end to end butt fit or any other type of suitable coupling between the two sheaths. When coupled together, as shown in FIG. 6A , the components shown in FIG. 6B move as a unit. For example, proximal sheath 60 , proximal shaft 64 , proximal filter 66 , distal shaft 68 , and the distal filter (not shown but within distal sheath 62 ) will rotate and translate axially (in the proximal or distal direction) as a unit. When proximal sheath 60 is retracted to allow proximal filter 66 to expand, as shown in FIG. 6B , distal sheath 62 can be independently rotated (“R”), steered (“S”), or translated axially (“T”) (either in the proximal “P” direction or distal “D” direction). The distal sheath therefore has 3 independent degrees of freedom: axial translation, rotation, and steering. The adaptation to have 3 independent degrees of freedom is advantageous when positioning the distal sheath in a target location, details of which are described below.
FIGS. 2A-2D illustrate a merely exemplary embodiment of a method of using any of the filter systems described herein. System 10 from FIGS. 1A-1D is shown in the embodiment in FIGS. 2A-2D . System 10 is advanced into the subject's right radial artery through an incision in the right arm. The system is advanced through the right subclavian artery and into the brachiocephalic trunk 11 , and a portion of the system is positioned within aorta 9 as can be seen in FIG. 2A (although that which is shown in FIG. 2A is not intended to be limiting).
Proximal sheath 12 is retracted proximally to allow proximal filter support element 15 to expand to an expanded configuration against the wall of the brachiocephalic trunk 11 , as is shown in FIG. 2B . Proximal filter element 17 is secured either directly or indirectly to support element 15 , and is therefore reconfigured to the configuration shown in FIG. 2B . The position of distal sheath 20 can be substantially maintained while proximal sheath 12 is retracted proximally. Once expanded, the proximal filter filters blood traveling through the brachiocephalic artery 11 , and therefore filters blood traveling into the right common carotid artery 7 . The expanded proximal filter is therefore in position to prevent foreign particles from traveling into the right common carotid artery 7 and into the cerebral vasculature.
Distal sheath 20 is then steered, or bent, and distal end 26 of distal sheath 20 is advanced into the left common carotid artery 13 , as shown in FIG. 2C . Guiding member 24 is thereafter advanced distally relative to distal sheath 20 , allowing the distal support element to expand from a collapsed configuration to a deployed configuration against the wall of the left common carotid artery 13 as shown in FIG. 2D . The distal filter element is also reconfigured into the configuration shown in FIG. 2D . Once expanded, the distal filter filters blood traveling through the left common carotid artery 13 . The distal filter is therefore in position to trap foreign particles and prevent them from traveling into the cerebral vasculature.
In several embodiments, the proximal and distal filter elements or frame elements comprise elastic or shape memory material causing the filters to expand as they exit their respective sheaths. In other embodiments, mechanical or hydraulic mechanisms may be used to expand each filter element. Once the filters are in place and expanded, an optional medical procedure can then take place, such as a valvuloplasty and/or replacement heart valve procedure. Any plaque or thrombus dislodged during the heart valve procedure that enters into the brachiocephalic trunk or the left common carotid artery will be trapped in the filters.
The filter system can thereafter be removed from the subject (or at any point in the procedure). In an exemplary embodiment, distal filter 22 is first retrieved back within distal sheath 20 to the collapsed configuration. To do this, guiding member 24 is retracted proximally relative to distal sheath 20 . This relative axial movement causes distal sheath 20 to engage strut 28 and begin to move strut 28 towards guiding member 24 . Support element 21 , which is coupled to strut 28 , begins to collapse upon the collapse of strut 28 . Filter element 23 therefore begins to collapse as well. Continued relative axial movement between guiding member 24 and distal sheath 20 continues to collapse strut 28 , support element 21 , and filter element 23 until distal filter 22 is retrieved and re-collapsed back within distal sheath 20 (as shown in FIG. 2C ). Any foreign particles trapped within distal filter element 23 are contained therein as the distal filter is re-sheathed. Distal sheath 20 is then steered into the configuration shown in FIG. 2B , and proximal sheath is then advanced distally relative to proximal filter 16 . This causes proximal filter 16 to collapse around distal shaft 18 , trapping any particles within the collapsed proximal filter. Proximal sheath 12 continues to be moved distally towards distal sheath 20 until in the position shown in FIG. 2A . The entire system 10 can then be removed from the subject.
In any of the embodiments mentioned herein, the filter or filters may alternatively be detached from the delivery catheter, and the delivery catheter removed leaving the filter behind. The filter or filters can be left in place permanently, or retrieved by snaring it with a retrieval catheter following a post procedure treatment period of time. Alternatively, the filters may remain attached to the catheter, and the catheter may be left in place post procedure for the treatment period of time. That treatment period may be at least one day, one week, three weeks, five weeks or more, depending upon the clinical circumstances. Patients with an indwelling filter or filters may be administered any of a variety of thrombolytic or anticoagulant therapies, including tissue plasminogen activator, streptokinase, coumadin, heparin and others known in the art.
An exemplary advantage of the systems described herein is that the delivery and retrieval system are integrated into the same catheter that stays in place during the procedure. Unloading and loading of different catheters, sheaths, or other components is therefore unnecessary. Having a system that performs both delivery and retrieval functions also reduces procedural complexity, time, and fluoroscopy exposure time. In addition, only a minimal portion of the catheter is in the aortic arch, thus greatly reducing the change of interference with other catheters.
FIGS. 7A-7B illustrate a perspective view and sectional view, respectively, of a portion of an exemplary filter system. The system includes distal shaft 30 and distal articulatable sheath 34 , coupled via coupler 32 . FIG. 7B shows the sectional view of plane A. Distal sheath 34 includes steering element 38 extending down the length of the sheath and within the sheath, which is shown as a pull wire. The pull wire can be, for example without limitation, stainless steel, tungsten, alloys of cobalt such as MP35N®, or any type of cable, either comprised of a single strand or two or more strands. Distal sheath 34 also includes spine element 36 , which is shown extending down the length of the sheath on substantially the opposite side of the sheath from steering element 38 . Spine element 36 can be, for example without limitation, a ribbon or round wire. Spine element 36 can be made from, for example, stainless steel or Nitinol. Spine element 36 resists axial expansion or compression of articulatable sheath 34 upon the application of an actuating axial pull or push force applied to steering element 38 , allowing sheath 34 to be deflected toward configuration 40 , as shown in phantom in FIG. 7A . FIG. 7C shows an alternative embodiment in which distal sheath 33 has a non-circular cross section. Also shown are spine element 35 and steering element 37 .
FIGS. 8A-8C illustrate views of exemplary pull wire 42 that can be incorporated into any distal sheaths described herein. Plane B in FIG. 8B shows a substantially circular cross-sectional shape of pull wire 42 in a proximal portion 44 of the pull wire, while plane C in FIG. 8C shows a flattened cross-sectional shape of distal portion 46 . Distal portion 46 has a greater width than height. The flattened cross-sectional shape of distal portion 46 provides for an improved profile, flexibility, and resistance to plastic deformation, which provides for improved straightening.
FIGS. 9A-C show an alternative embodiment of distal sheath 48 that includes slots 50 formed therein. The slots can be formed by, for example, grinding, laser cutting or other suitable material removal from distal sheath 48 . Alternatively, the slots can be the openings between spaced apart coils or filars of a spring. The characteristics of the slots can be varied to control the properties of the distal sheath. For example, the pitch, width, depth, etc., of the slots can be modified to control the flexibility, compressibility, torsional responsiveness, etc., of distal sheath 48 . More specifically, the distal sheath 48 can be formed from a length of stainless steel hypotubing. Transverse slots 50 are preferably formed on one side of the hypotubing, leaving an opposing spine which provides column strength to avoid axial compression or expansion upon application of an axial force to the pull wire and also limits deflection to a desired single plane or predetermined planes.
FIG. 9B shows a further embodiment of the distal sheath in greater detail. In this embodiment distal sheath 48 includes a first proximal articulatable hypotube section 49 . Articulatable hypotube section 49 is fixed to distal shaft 30 (not shown in FIG. 9A ). A second distal articulatable section 51 is secured to first proximal section 49 . Pull wire 38 extends from the handle through distal shaft section 49 and is affixed to a distal portion of distal shaft portion 51 . This embodiment allows for initial curvature of distal sheath proximal section 49 in a first direction such as away from the outer vessel wall in response to proximal retraction of the pull wire 38 . Distal sheath distal section 51 is then articulated to a second curvature in a second, opposite direction. This second curvature of distal shaft section 51 is adjustable based upon tension or compression loading of the sheath section by pull wire 38 . Alternatively, a first pull wire can be attached at a distal portion of section 49 and a second pull wire can be attached at a distal portion of section 51 to allow independent deflection of the two deflection sections.
As shown in FIG. 9B , pull wire 38 in a single pull wire embodiment crosses to an opposite side of the inner lumen defined by sections 49 and 51 from the slots 50 as it transitions from the first distal sheath proximal section 49 to second distal sheath distal section 51 . As best shown in FIG. 9C , distal sheath proximal section 49 would articulate first to initialize a first curve, concave in a first direction as the slots 50 compress in response to proximal retraction of the pull wire 38 . As the tension on pull wire 38 is increased and the slots bottom out, distal sheath distal section 51 begins to form a second curve concave in a second direction opposite to the direction of the first curve, due to pull wire 38 crossing the inner diameter of the lumen through distal sheath sections 49 and 51 . As can be seen in FIG. 9C , as it nears and comes to the maximum extent of its articulation, distal sheath distal section 51 can take the form of a shepherd's staff or crook.
Distal sheath proximal section 49 could take the form of a tubular slotted element or a pre-shaped curve that utilizes a memory material such as Nitinol or any other material exhibiting suitable properties. In some embodiments outer diameter of distal sheath proximal section 49 is between 0.02 inches and 0.2 inches. In certain embodiments, the outer diameter is between 0.05 inches and 0.1 inches, or between 0.06 inches and 0.075 inches. In some embodiments, the inner diameter of distal sheath proximal section 49 is between 0.02 inches and 0.2 inches. In certain embodiments, the inner diameter is between 0.03 inches and 0.08 inches or between 0.05 inches and 0.07 inches. In several embodiments, the length of distal sheath proximal section 49 may measures between 0.1 inches and 2.5 inches. In some embodiments, the length of distal sheath proximal section 49 may measure between about 0.50 inches and 1 inch or between 0.6 inches and 0.8 inches. In certain embodiments, the length of distal sheath proximal section 49 may be longer than 2.5 inches. It is understood that these sizes and proportions will vary depending on the specific application and those listed herein are not intended to be limiting. Transverse slots 50 can measure from about 0.002 inches to about 0.020 inches in width (measured in the axial direction) depending on the specific application and the degree of curvature desired. In some embodiments the slots can measure less than 0.002 inches or greater than 0.02 inches. In certain embodiments, the slots 50 can measure about 0.002 inches to 0.01 inches or between 0.006 and 0.01 inches.
The curvature of proximal section 49 may be varied from about 0 degrees to 90 degrees or more depending on the width and number of the slots 50 . In several embodiments, the maximum degree of deflection ranges from about 15 degrees to about 75 degrees, from about 45 degrees to about 60 degrees. Commencement of deflection of distal section 51 can occur prior to, simultaneously with or following commencement of deflection of proximal section 49 based upon the relative stiffness of the sections or configuration of the pull wire as will be apparent to those of skill in the art.
The distal sheath is configured such that the maximum net curvature between the primary axis of the catheter prior to any deflection and the distal tip axis is between about 90 and about 220 degrees. In other embodiments, the maximum deflection is between about 120 degrees and about 200 degrees, or between about 150 degrees and about 180 degrees. When the distal sheath is in its curved configuration, with a net deflection from the primary axis of at least about 150 degrees, the lateral distance between the primary axis and the distal tip ranges from about 5 mm to about 15 mm.
The position of at least a second group of slots 50 may also be rotationally displaced about the axis of the tube with respect to a first group of slots to allow a first portion of the distal sheath to bend in a first plane and a second portion of the distal sheath to bend out-of-plane to access more complex anatomy as shown in FIGS. 9D and 9E . The second set of slots 50 may be displaced circumferentially from the first set of slots by about 5 degrees to about 90 degrees. In certain embodiments, the slots are displaced from about 15 to 60 degrees or from about 20 to about 40 degrees. The curvature of the out of plane curve may vary from about 20 degrees to about 75 degrees, but in some embodiments, the out of plane curvature may be less than 20 degrees or greater than 75 degrees. In several embodiments, the curvature of the out of plane curve is from about 20 degrees to 40 degrees, from about 30 degrees to about 50 degrees, from about 40 degrees to about 60 degrees, or from about 50 degrees to 75 degrees. Alternatively, this out-of-plane bend could be achieved by prebending the tube after laser cutting the slots to create a bias or by any other method which would create a bias. The shape could also be multi-plane or bidirectional where the tube would bend in multiple directions within the same section of laser cut tube.
In several embodiments, distal sheath distal section 51 is a selectable curve based upon the anatomy and vessel location relative to one another. This section 51 could also be a portion of the laser cut element or a separate construction where a flat ribbon braid could be utilized. It may also include a stiffening element or bias ribbon to resist permanent deformation. In one embodiment it would have a multitude of flat ribbons staggered in length to create a constant radius of curvature under increased loading.
In some embodiments, distal sheath 34 incorporates a guidewire lumen 58 through which a guidewire may pass as shown in FIG. 9F . Alternatively, in FIG. 9G , the guidewire lumen is coaxial with guiding member lumen 59 . Removing the guidewire lumen from the wall of distal sheath 34 has the added benefit of increasing the distal sheath luminal cross sectional area, reducing deployment and retrieval forces, and increasing the capacity for debris within the distal sheath.
FIGS. 10A and 10B illustrate a portion of exemplary distal sheath 52 that is adapted to be multi-directional, and is specifically shown to be bi-directional. Distal sheath 52 is adapted to be steered towards the configurations 53 and 54 shown in phantom in FIG. 10A . FIG. 10B is a sectional view in plane D, showing spinal element 55 and first and second steering elements 56 disposed on either side of spinal element 55 . Steering elements 56 can be similar to steering element 38 shown in FIG. 7B . The steering elements can be disposed around the periphery of distal sheath at almost any location.
Incorporating steerable functionality into tubular devices is known in the area of medical devices. Any such features can be incorporated into the systems herein, and specifically into the articulatable distal sheaths.
In some embodiments the distal sheath includes radiopaque markers to visualize the distal sheath under fluoroscopy. In some embodiments the distal sheath has radiopaque markers at proximal and distal ends of the sheath to be able to visualize the ends of the sheath.
An exemplary advantage of the filter systems described herein is the ability to safely and effectively position the distal sheath. In some uses, the proximal filter is deployed in a first bodily lumen, and the distal filter is deployed in a second bodily lumen different than the first. For example, as shown in FIG. 2D , the proximal filter is deployed in the brachiocephalic trunk and the distal filter is deployed in a left common carotid artery. While both vessels extend from the aortic arch, the position of the vessel openings along the aortic arch varies from patient-to-patient. That is, the distance between the vessel openings can vary from patient to patient. Additionally, the angle at which the vessels are disposed relative to the aorta can vary from patient to patient. Additionally, the vessels do not necessarily lie within a common plane, although in many anatomical illustrations the vessels are typically shown this way. For example, FIGS. 11A-11C illustrate merely exemplary anatomical variations that can exist. FIG. 11A is a top view (i.e., in the superior-to-inferior direction) of aorta 70 , showing relative positions of brachiocephalic trunk opening 72 , left common carotid artery opening 74 , and left subclavian opening 76 . FIG. 11B is a side sectional view of aortic 78 illustrating the relative angles at which brachiocephalic trunk 80 , left common carotid artery 82 , and left subclavian artery 84 can extend from aorta 78 . FIG. 11C is a side sectional view of aorta 86 , showing vessel 88 extending from aorta 86 at an angle. Any or all of the vessels extending from aorta 86 could be oriented in this manner relative to the aorta. FIGS. 11D and 11E illustrate that the angle of the turn required upon exiting the brachiocephalic trunk 92 / 100 and entering the left common carotid artery 94 / 102 can vary from patient to patient. Due to the patient-to-patient variability between the position of the vessels and their relative orientations, a greater amount of control of the distal sheath increases the likelihood that the distal filter will be positioned safely and effectively. For example, a sheath that only has the ability to independently perform one or two of rotation, steering, and axial translation may not be adequately adapted to properly and safely position the distal filter in the left common carotid artery. All three degrees of independent motion as provided to the distal sheaths described herein provide important clinical advantages. Typically, but without intending to be limiting, a subject's brachiocephalic trunk and left carotid artery are spaced relatively close together and are either substantially parallel or tightly acute (see, e.g., FIG. 11E ).
FIGS. 12A and 12B illustrates an exemplary curvature of a distal sheath to help position the distal filter properly in the left common carotid artery. In FIGS. 12A and 12B , only a portion of the system is shown for clarity, but it can be assumed that a proximal filter is included, and in this example has been expanded in brachiocephalic trunk 111 . Distal shaft 110 is coupled to steerable distal sheath 112 . Distal sheath 112 is steered into the configuration shown in FIG. 12B . The bend created in distal sheath 112 , and therefore the relative orientations of distal sheath 112 and left common carotid artery 113 , allow for the distal filter to be advanced from distal sheath 112 into a proper position in left common carotid 113 . In contrast, the configuration of distal sheath 114 shown in phantom in FIG. 12A illustrates how a certain bend created in the distal sheath can orient the distal sheath in such a way that the distal filter will be advanced directly into the wall of the left common carotid (depending on the subject's anatomy), which can injure the wall and prevent the distal filter from being properly deployed. Depending on the angulation, approach angle, spacing of the openings, etc., a general U-shaped curve (shown in phantom in FIG. 12A ) may not be optimal for steering and accessing the left common carotid artery from the brachiocephalic trunk.
In some embodiments the distal sheath is adapted to have a preset curved configuration. The preset configuration can have, for example, a preset radius of curvature (or preset radii of curvature at different points along the distal sheath). When the distal sheath is articulated to be steered to the preset configuration, continued articulation of the steering element can change the configuration of the distal sheath until is assumes the preset configuration. For example, the distal sheath can comprise a slotted tube with a spine extending along the length of the distal sheath. Upon actuation of the steering component, the distal sheath will bend until the portions of the distal sheath that define the slots engage, thus limiting the degree of the bend of the distal sheath. The curve can be preset into a configuration that increases the likelihood that the distal filter will, when advanced from the distal sheath, be properly positioned within the left common carotid artery.
FIGS. 13A and 13B illustrate alternative distal sheath and distal shaft portions of an exemplary filter system. FIGS. 13A and 13B only show distal shaft 120 and distal sheath 122 for clarity, but the system may also includes a proximal filter (not shown but has been deployed in brachiocephalic trunk). The distal shaft/distal sheath combination has a general S-bend configuration, with distal shaft 120 including a first bend 124 in a first direction, and distal sheath 122 configured to assume bend 126 in a second direction, wherein the first and second bends form the general S-bend configuration. FIG. 13B shows distal sheath 122 pulled back in the proximal direction relative to the proximal filter to seat the curved distal sheath against the bend. This both helps secure the distal sheath in place as well as reduces the cross sectional volume of the filter system that is disposed with the aorta. The distal shaft and distal sheath combination shown in FIGS. 13A and 13B can be incorporated into any of the filter systems described herein.
Exemplary embodiments of the delivery and deployment of a multi-filter embolic protection apparatus will now be described with reference to FIGS. 2A-2D , 13 A, 13 B, 14 , 1 , 3 , 4 and 5 . More particularly, the delivery and deployment will be described with reference to placement of the filter system in the brachiocephalic and left common carotid arteries. The preferred access for the delivery of the multi-filter system 10 is from the right radial or right brachial artery, however other access locations such as the right subclavian artery are possible. The system is then advanced through the right subclavian artery to a position within the brachiocephalic artery 11 . At this point, proximal filter 16 may be deployed within into expanding engagement with the inner lining of brachiocephalic artery 11 . Alternatively, access to the left common carotid could be gained prior to deployment of proximal filter 16 . Deployment of proximal filter 16 protects both the brachiocephalic artery 11 and the right common carotid artery 7 against emboli and other foreign bodies in the bloodstream.
Entry into the aortic space, as illustrated in FIG. 3 , is then accomplished by further advancement of the system from the brachiocephalic trunk. During this step, the filter system will tend to hug the outer portion of the brachiocephalic trunk as shown in FIG. 4 . Initial tensioning of pull wire 38 causes distal sheath 48 to move the catheter-based filter system off the wall of the brachiocephalic artery just before the ostium or entrance into the aorta, as shown in FIG. 4 . As the catheter path will hug the outer wall of the brachial cephalic artery, a curve directed away from this outer wall will allow additional space for the distal portion of the distal sheath to curve into the left common carotid artery, as shown in FIG. 5 .
The width of slots 50 will determine the amount of bending allowed by the tube when tension is applied via pull wire 38 . For example, a narrow width slot would allow for limited bending where a wider slot would allow for additional bending due to the gap or space removed from the tube. As the bending is limited by the slot width, a fixed shape or curve may be obtained when all slots are compressed and touching one another. Additional features such as chevrons may be cut into the tube to increase the strength of the tube when compressed. Other means of forming slots could be obtained with conventional techniques such as chemical etching, welding of individual elements, mechanical forming, metal injection molding or other conventional methods.
Once in the aortic space, the distal sheath is further tensioned to adjust the curvature of the distal shaft distal section 51 , as shown in FIG. 9B . The amount of deflection is determined by the operator of the system based on the particular patient anatomy.
Other techniques to bias a catheter could be external force applications to the catheter and the vessel wall such as a protruding ribbon or wire from the catheter wall to force the catheter shaft to a preferred position within the vessel. Flaring a radial element from the catheter central axis could also position the catheter shaft to one side of the vessel wall. Yet another means would be to have a pull wire external to the catheter shaft exiting at one portion and reattaching at a more distal portion where a tension in the wire would bend or curve the catheter at a variable rate in relation to the tension applied.
This multi-direction and variable curvature of the distal sheath allows the operator to easily direct the filter system, or more particularly, the distal sheath section thereof, into a select vessel such as the left common carotid artery or the left innominate artery. Furthermore, the filter system allows the operator to access the left common carotid artery without the need to separately place a guidewire in the left common carotid artery. The clinical variations of these vessels are an important reason for the operator to have a system that can access differing locations and angulations between the vessels. The filter systems described herein will provide the physician complete control when attempting to access these vessels.
Once the distal sheath is oriented in the left common carotid, the handle can be manipulated by pulling it and the filter system into the bifurcation leaving the aortic vessel clear of obstruction for additional catheterizations, an example of which is shown in FIG. 12B . At this time, distal filter 22 can be advanced through proximal shaft 14 and distal shaft 18 into expanding engagement with left common carotid artery 13 .
FIG. 14 illustrates a portion of an exemplary system including distal shaft 130 and distal sheath 132 . Distal sheath is adapted to be able to be steered into what can be generally considered an S-bend configuration, a shepherd's staff configuration, or a crook configuration, comprised of first bend 131 and second bend 133 in opposite directions. Also shown is rotational orb 134 , defined by the outer surface of the distal sheath as distal shaft 130 is rotated at least 360 degrees in the direction of the arrows shown in FIG. 14 . If a typical aorta is generally in the range from about 24 mm to about 30 mm in diameter, the radius of curvature and the first bend in the S-bend can be specified to create a rotational orb that can reside within the aorta (as shown in FIG. 14 ), resulting in minimal interference with the vessel wall and at the same time potentially optimize access into the left common carotid artery. In other distal sheath and/or distal shaft designs, such as the one shown in FIG. 12A , the rotational orb created by the rotation of distal shaft 110 is significantly larger, increasing the risk of interference with the vessel wall and potentially decreasing the access into the left common carotid artery. In some embodiments, the diameter of the rotation orb for a distal sheath is less than about 25 mm.
Referring back to FIG. 12A , distal sheath 112 , in some embodiments, includes a non-steerable distal section 121 , an intermediate steerable section 119 , and a proximal non-steerable section 117 . When the distal sheath is actuated to be steered, only steerable portion 119 bends into a different configuration. That is, the non-steerable portions retain substantially straight configurations. The distal non-steerable portion remains straight, which can allow the distal filter to be advanced into a proper position in the left common carotid artery.
While FIG. 12A shows distal sheath 112 in a bent configuration, the distal sheath is also positioned within the lumen of the aorta. In this position, the distal sheath can interfere with any other medical device or instrument that is being advanced through the aorta. For example, in aortic valve replacement procedures, delivery device 116 , with a replacement aortic valve disposed therein, is delivered through the aorta as shown in FIG. 12B . If components of the filter system are disposed within the aorta during this time, delivery device 116 and the filter system can hit each other, potentially damaging either or both systems. The delivery device 116 can also dislodge one or both filters if they are in the expanded configurations. The filter system can additionally prevent the delivery device 116 from being advanced through the aorta. To reduce the risk of contact between delivery device 116 and distal sheath 112 , distal sheath 112 (and distal shaft 110 ) is translated in the proximal direction relative to the proximal filter (which in this embodiment has already been expanded but is not shown), as is shown in FIG. 12B . Distal sheath 112 is pulled back until the inner curvature of distal sheath 112 is seated snugly with the vasculature 115 disposed between the brachiocephalic trunk 111 and the left common carotid artery 113 . This additional seating step helps secure the distal sheath in place within the subject, as well as minimize the amount of the filter system present in the aortic arch. This additional seating step can be incorporated into any of the methods described herein, and is an exemplary advantage of having a distal sheath that has three degrees of independent motion relative to the proximal filter. The combination of independent rotation, steering, and axial translation can be clinically significant to ensure the distal filter is properly positioned in the lumen, as well as making sure the filter system does not interfere with any other medical devices being delivered to the general area inside the subject.
An additional advantage of the filter systems herein is that the distal sheath, when in the position shown in FIG. 12B , will act as a protection element against any other medical instruments being delivered through the aorta (e.g., delivery device 116 ). Even if delivery device 116 were advanced such that it did engage distal sheath 112 , distal sheath 112 is seated securely against tissue 115 , thus preventing distal sheath 112 from being dislodged. Additionally, distal sheath 112 is stronger than, for example, a wire positioned within the aorta, which can easily be dislodged when hit by delivery device 116 .
FIGS. 15A-15D illustrate alternative embodiments of the coupling of the distal shaft and distal sheath. In FIG. 15A distal shaft 140 is secured to distal sheath 142 by coupler 144 . Shaft 140 has a low profile to allow for the collapse of the proximal filter (see FIG. 1C ). Shaft 140 also has column strength to allow for axial translation, has sufficient torque transmission properties, and is flexible. The shaft can have a support structure therein, such as braided stainless steel. For example, the shaft can comprise polyimide, Polyether ether ketone (PEEK), Nylon, Pebax, etc. FIG. 15B illustrates an alternative embodiment showing tubular element 146 , distal shaft 148 , and distal sheath 150 . Tubular element 146 can be a hypotube made from stainless steel, Nitinol, etc. FIG. 15C illustrates an exemplary embodiment that includes distal shaft 152 , traction member 154 , and distal sheath 156 . Traction member 154 is coupled to shaft 152 and shaft 152 is disposed therein. Traction member 154 couples to shaft 152 for torquebility, deliverability, and deployment. Traction member 154 can be, for example without limitation, a soft silicone material, polyurethane, polyimide, or other material having suitable properties. FIG. 15D shows an alternative embodiment in which the system includes bushing 162 disposed over distal shaft 158 , wherein distal shaft 158 is adapted to rotate within bushing 162 . The system also includes stop 160 secured to distal shaft 158 to substantially maintain the axial position of bushing 162 . When the system includes bushing 162 , distal sheath 164 can be rotated relative to the proximal sheath and the proximal filter when the distal sheath and proximal sheath are in the delivery configuration (see FIG. 1B ).
FIG. 16 illustrates an exemplary embodiment of filter system 170 in which distal sheath 172 is biased to a curved configuration 174 . The biased curved configuration is adapted to facilitate placement, delivery, and securing at least the distal filter. As shown, the distal sheath is biased to a configuration that positions the distal end of the distal sheath towards the left common carotid artery.
FIG. 17 illustrates a portion of an exemplary filter system and its method of use. FIG. 17 shows a system and portion of deployment similar to that shown in FIG. 2D , but distal sheath 182 has been retracted proximally relative to guiding member 190 and distal filter 186 . Distal sheath 182 has been retracted substantially from the aortic arch and is substantially disposed with the brachiocephalic trunk. Guiding member 190 can have preset curve 188 adapted to closely mimic the anatomical curve between the brachiocephalic trunk and the left common carotid artery, thus minimizing the amount of the system that is disposed within the aorta. As shown, distal sheath 182 has been retracted proximally relative to proximal filter 180 .
FIG. 18A is a perspective view of a portion of an exemplary embodiment of a filter system, while FIG. 18B is a close-up view of a portion of the system shown in FIG. 18A . The distal sheath and the distal filter are not shown in FIGS. 18A and 18B for clarity. The system includes proximal filter 200 coupled to proximal shaft 202 , and push rod 206 coupled to proximal shaft 202 . A portion of proximal sheath 204 is shown in FIG. 18A in a retracted position, allowing proximal filter 200 to expand to an expanded configuration. Only a portion of proximal sheath 204 is shown, but it generally extends proximally similar to push rod 206 . The proximal end of proximal shaft 202 is beveled and defines an aspiration lumen 216 , which is adapted to receive an aspirator (not shown) to apply a vacuum to aspirate debris captured within distally facing proximal filter 200 . Push rod 206 extends proximally within proximal sheath 204 and is coupled to an actuation system outside of the subject, examples of which are described below. Push rod 206 takes up less space inside proximal sheath 204 than proximal shaft 202 , providing a lower profile.
The system also includes proximal seal 214 disposed on the outer surface of proximal shaft 202 and adapted to engage the inner surface of the proximal sheath. Proximal seal 214 prevents bodily fluids, such as blood, from entering the space between proximal sheath 204 and proximal shaft 202 , thus preventing bodily fluids from passing proximally into the filter system. The proximal seal can be, for example without limitation, a molded polymer. The proximal seal can also be machined as part of the proximal shaft, such that they are not considered two separate components.
In some specific embodiments the push rod is between 0.001 inches and 0.05 inches in diameter. In some embodiments, the diameter is between 0.01 inches and 0.025 inches in diameter. The pushrod can be constructed from any number of polymeric or metal materials, such as stainless steel. The proximal shaft can be, for example without limitation, an extruded or molded plastic, a hypotube (e.g., stainless steel), machined plastic, metal, etc.
Proximal filter 200 includes filter material 208 , which comprises pores adapted to allow blood to pass therethrough, while debris does not pass through the pores and is captured within the filter material. Proximal filter 200 also includes strut 210 that extends from proximal shaft 202 to expansion support 212 . Expansion support 212 has a generally annular shape but that is not intended to be limiting. Proximal filter 200 also has a leading portion 220 and a trailing portion 222 . Leading portion 220 generally extends further distally than trailing portion 222 to give filter 200 a generally canted configuration relative to the proximal shaft. The canted design provides for decreased radial stiffness and a better collapsed profile. Strut 210 and expansion support 212 generally provide support for filter 200 when in the expanded configuration, as shown in FIG. 18A .
FIGS. 19A-19C illustrate exemplary embodiments of proximal filters and proximal shafts that can be incorporated into any of the systems herein. In FIG. 19A , filter 230 has flared end 232 for improved filter-wall opposition. FIG. 19B shows proximal shaft 244 substantially co-axial with vessel 246 in which filter 240 is expanded. Vessel 246 and shaft 244 have common axis 242 . FIG. 19C illustrates longitudinal axis 254 of shaft 256 not co-axial with axis 252 of lumen 258 in which filter 250 is expanded.
FIGS. 20A and 20B illustrate an exemplary embodiment including proximal filter 260 coupled to proximal shaft 262 . Filter 260 includes filter material 264 , including slack material region 268 adapted to allow the filter to collapse easier. Filter 260 is also shown with at least one strut 270 secured to shaft 262 , and expansion support 266 . As shown in the highlighted view in FIG. 20B , filter 260 includes seal 274 , radiopaque coil 276 (e.g., platinum), support wire 278 (e.g., Nitinol wire), and filter material 264 . Any of the features in this embodiment can be included in any of the filter systems described herein.
FIG. 21 illustrates an exemplary embodiment of a proximal filter. Proximal filter 280 is coupled to proximal shaft 282 . Proximal filter 280 includes struts 286 extending from proximal shaft 282 to strut restraint 288 , which is adapted to slide axially over distal shaft 284 . Proximal filter 280 also includes filter material 290 , with pores therein, that extends from proximal shaft 282 to a location axially between proximal shaft 282 and strut restraint 288 . Debris can pass through struts 286 and become trapped within filter material 290 . When proximal filter 280 is collapsed within a proximal sheath (not shown), struts 286 elongate and move radially inward (towards distal shaft 284 ). Strut restraint 288 is adapted to move distally over distal shaft 284 to allow the struts to move radially inward and extend a greater length along distal shaft 284 .
FIGS. 22A and 22B illustrate an exemplary embodiment of a proximal filter that can be incorporated into any filter system described herein. The system includes proximal filter 300 and proximal sheath 302 , shown in a retracted position in FIG. 22A . Proximal filter 300 includes valve elements 304 in an open configuration in FIG. 22A . When valve elements 304 are in the open configuration, foreign particles 306 can pass through opening 308 and through the valve and become trapped in proximal filter 300 , as is shown in FIG. 22A . To collapse proximal filter 300 , proximal sheath 302 is advanced distally relative to proximal filter 300 . As the filter begins to collapse, the valve elements are brought closer towards one another and into a closed configuration, as shown in FIG. 22B . The closed valve prevents extrusion of debris during the recapture process.
The distal filters shown are merely exemplary and other filters may be incorporated into any of the systems herein. FIG. 23A illustrates a portion of an exemplary filter system. The system includes guiding member 340 (distal sheath not shown), strut 342 , expansion support 344 , and filter element 346 . Strut 342 is secured directly to guiding member 340 and strut 342 is secured either directly or indirectly to expansion support 344 . Filter material 346 is secured to expansion support 344 . Distal end 348 of filter material 346 is secured to guiding member 340 .
FIG. 23B illustrates a portion of an exemplary filter system. The system includes guiding element 350 , strut support 352 secured to guiding element 350 , strut 354 , expansion support 356 , and filter material 358 . Strut support 352 can be secured to guiding element 350 in any suitable manner (e.g., bonding), and strut 354 can be secured to strut support 352 in any suitable manner.
FIG. 23C illustrates a portion of an exemplary filter system. The system includes guiding element 360 , strut support 362 secured to guiding element 360 , strut 364 , expansion support 366 , and filter material 368 . Expansion support 366 is adapted to be disposed at an angle relative to the longitudinal axis of guiding member 360 when the distal filter is in the expanded configuration. Expansion support 366 includes trailing portion 362 and leading portion 361 . Strut 364 is secured to expansion support 366 at or near leading portion 361 . FIG. 23D illustrates an exemplary embodiment that includes guiding member 370 , strut support 372 , strut 374 , expansion support 376 , and filter material 378 . Expansion support 376 includes leading portion 373 , and trailing portion 371 , wherein strut 374 is secured to expansion element 376 at or near trailing portion 371 . Expansion support 376 is disposed at an angle relative to the longitudinal axis of guiding member 370 when the distal filter is in the expanded configuration.
FIG. 23E illustrates an exemplary embodiment of a distal filter in an expanded configuration. Guiding member 380 is secured to strut support 382 , and the filter includes a plurality of struts 384 secured to strut support 382 and to expansion support 386 . Filter material 388 is secured to expansion support 386 . While four struts are shown, the distal filter may include any number of struts.
FIG. 23F illustrates an exemplary embodiment of a distal filter in an expanded configuration. Proximal stop 392 and distal stop 394 are secured to guiding member 390 . The distal filter includes tubular member 396 that is axially slidable over guiding member 390 , but is restricted in both directions by stops 392 and 394 . Strut 398 is secured to slidable member 396 and to expansion support 393 . Filter material 395 is secured to slidable member 396 . If member 396 slides axially relative to guiding member 390 , filter material 395 moves as well. Member 396 is also adapted to rotate in the direction “R” relative to guiding member 390 . The distal filter is therefore adapted to independently move axially and rotationally, limited in axial translation by stops 392 and 394 . The distal filter is therefore adapted such that bumping of the guiding member or the distal sheath will not disrupt the distal filter opposition, positioning, or effectiveness.
As shown in FIGS. 23A-23B , in some embodiments, the strut 342 , 354 has a straight configuration. A straight configuration may allow for a shorter attachment between the filter and the guiding member. In other embodiments, as shown in FIGS. 23C-23D , the strut 364 , 374 , takes a curved configuration. In still other embodiments, the strut has two or more curves. For example, the strut may take a sinusoidal configuration and transition from a first curve to the opposite curve to aid in transition to the filter frame. In some embodiments, the first curve may have a larger radius than the opposite curve. In still other embodiments, the first curve may have a smaller radius than the opposite curve.
FIGS. 24A-24C illustrate exemplary embodiments in which the system includes at least one distal filter positioning, or stabilizing, anchor. The positioning anchor(s) can help position the distal anchor in a proper position and/or orientation within a bodily lumen. In FIG. 24A the system includes distal filter 400 and positioning anchor 402 . Anchor 402 includes expandable stent 404 and expandable supports 406 . Supports 406 and filter 400 are both secured to the guiding member. Anchor 402 can be any suitable type of expandable anchor, such as, for example without limitation, stent 404 . Anchor 402 can be self-expandable, expandable by an expansion mechanism, or a combination thereof. In FIG. 24A , stent 404 can alternatively be expanded by an expansion balloon. Anchor 402 is disposed proximal to filter 400 . FIG. 24B illustrates an embodiment in which the system includes first and second anchors 412 and 414 , one of which is proximal to filter 410 , while the other is distal to filter 410 . FIG. 24C illustrates an embodiment in which anchor 422 is distal relative to filter 420 .
In some embodiments the distal filter is coupled, or secured, to a guiding member that has already been advanced to a location within the subject. The distal filter is therefore coupled to the guiding member after the distal filter has been advanced into the subject, rather than when the filter is outside of the subject. Once coupled together inside the subject, the guiding member can be moved (e.g., axially translated) to control the movement of the distal filter. In some embodiments the guiding member has a first locking element adapted to engage a second locking element on the distal filter assembly such that movement of the guiding member moves the distal filter in a first direction. In some embodiments the distal filter assembly has a third locking element that is adapted to engage the first locking element of the guiding member such that movement of the guiding member in a second direction causes the distal filter to move with the guiding member in the second direction. The guiding member can therefore be locked to the distal filter such that movement of the guiding member in a first and a second direction will move the distal filter in the first and second directions.
By way of example, FIGS. 25A-25D illustrate an exemplary embodiment of coupling the distal filter to a docking wire inside of the subject, wherein the docking wire is subsequently used to control the movement of the distal filter relative to the distal sheath. In FIG. 25A , guide catheter 440 has been advanced through the subject until the distal end is in or near the brachiocephalic trunk 441 . A docking wire, comprising a wire 445 , locking element 442 , and tip 444 , has been advanced through guide catheter 440 , either alone, or optionally after guiding wire 446 has been advanced into position. Guiding wire 446 can be used to assist in advancing the docking wire through guide catheter 440 . As shown, the docking wire has been advanced from the distal end of guide catheter 440 . After the docking wire is advanced to the desired position, guide catheter 440 , and if guiding wire 446 is used, are removed from the subject, leaving the docking wire in place within the subject, as shown in FIG. 25B . Next, as shown in FIG. 25C , the filter system, including proximal sheath 448 with a proximal filter in a collapsed configuration therein (not shown), distal sheath 450 , with a distal filter assembly (not shown) partially disposed therein, is advanced over wire 445 until a locking portion of the distal filter (not shown but described in detail below) engages locking element 442 . The distal filter assembly will thereafter move (e.g., axially) with the docking wire. Proximal sheath 448 is retracted to allow proximal filter 454 to expand (see FIG. 25D ). Distal sheath 450 is then actuated (e.g., bent, rotated, and/or translated axially) until it is in the position shown in FIG. 25D . A straightened configuration of the distal sheath is shown in phantom in FIG. 25D , prior to bending, proximal movement, and/or bending. The docking wire is then advanced distally relative to distal sheath 450 , which advances distal filter 456 from distal sheath 450 , allowing distal filter 456 to expand inside the left common carotid artery, as shown in FIG. 25D .
FIGS. 26A-26D illustrate an exemplary method of preparing an exemplary distal filter assembly for use. FIG. 26A illustrates a portion of the filter system including proximal sheath 470 , proximal filter 472 is an expanded configuration, distal shaft 474 , and articulatable distal sheath 476 . Distal filter assembly 478 includes an elongate member 480 defining a lumen therein. Elongate member 480 is coupled to distal tip 490 . Strut 484 is secured both to strut support 482 , which is secured to elongate member 480 , and expansion support 486 . Filter element 488 has pores therein and is secured to expansion support 486 and elongate member 480 . To load distal filter assembly 478 into distal sheath 476 , loading mandrel 492 is advanced through distal tip 490 and elongate member 480 and pushed against distal tip 490 until distal filter assembly 478 is disposed within distal sheath 476 , as shown in FIG. 26C . Distal tip 490 of the filter assembly remains substantially distal to distal sheath 476 , and is secured to the distal end of distal sheath 476 . Distal tip 490 and distal sheath 476 can be secured together by a frictional fit or other type of suitable fit that disengages as described below. Loading mandrel 492 is then removed from the distal filter and distal sheath assembly, as shown in FIG. 26D .
FIG. 26E illustrates docking wire 500 including wire 502 , lock element 504 , and distal tip 506 . Docking wire 500 is first advanced to a desired position within the subject, such as is shown in FIG. 25B . The assembly from FIG. 26D is then advanced over docking wire, wherein distal tip 490 is first advanced over the docking wire. As shown in the highlighted view in FIG. 26F , distal tip 490 of the distal filter assembly includes first locking elements 510 , shown as barbs. As the filter/sheath assembly continues to be distally advanced relative to the docking wire, the docking wire locking element 504 pushes locks 510 outward in the direction of the arrows in FIG. 26F . After lock 504 passes locks 510 , locks 510 spring back inwards in the direction of the arrows shown in FIG. 26G . In this position, when docking wire 500 is advanced distally (shown in FIG. 26F ), lock element 504 engages with lock elements 510 , and the lock element 504 pushes the distal filter assembly in the distal direction. In this manner the distal filter can be distally advanced relative to the distal sheath to expand the distal filter. Additionally, when the docking wire is retracted proximally, locking element 504 engages the distal end 512 of elongate member 480 and pulls the distal filter in the proximal direction. This is done to retrieve and/or recollapse the distal filter back into the distal sheath after it has been expanded.
FIGS. 27A and 27B illustrate an exemplary embodiment in which guiding member 540 , secured to distal filter 530 before introduction into the subject is loaded into articulatable distal sheath 524 . The system also includes proximal filter 520 , proximal sheath 522 , and distal shaft 526 . FIG. 27B shows the system in a delivery configuration in which both filters are collapsed.
FIGS. 28A-28E illustrate an exemplary distal filter assembly in collapsed and expanded configurations. In FIG. 28A , distal filter assembly 550 includes a distal frame, which includes strut 554 and expansion support 555 . The distal frame is secured to floating anchor 558 , which is adapted to slide axially on elongate member 564 between distal stop 560 and proximal stop 562 , as illustrated by the arrows in FIG. 28A . The distal filter assembly also includes membrane 552 , which has pores therein and is secured at its distal end to elongate member 564 . The distal filter assembly is secured to a guiding member, which includes wire 566 and soft distal tip 568 . The guiding member can be, for example, similar to the docking wire shown in FIGS. 26A-26E above, and can be secured to the distal filter assembly as described in that embodiment.
The floating anchor 558 allows filter membrane 552 to return to a neutral, or at-rest, state when expanded, as shown in FIG. 28A . In its neutral state, there is substantially no tension applied to the filter membrane. The neutral deployed state allows for optimal filter frame orientation and vessel apposition. In the neutral state shown in FIG. 28A , floating anchor 558 is roughly mid-way between distal stop 560 and proximal stop 562 , but this is not intended to be a limiting position when the distal filter is in a neutral state.
FIG. 28B illustrates the distal filter being sheathed into distal sheath 572 . During the sheathing process, the distal filter is collapsed from an expanded configuration (see FIG. 28A ) towards a collapsed configuration (see FIG. 28C ). In FIG. 28B , distal sheath 572 is moving distally relative to the distal filter. The distal end of the distal sheath 572 engages with strut 554 as it is advanced distally, causing the distal end of strut 554 to moves towards elongate member 564 . Strut 554 can be thought of as collapsing towards elongate member 564 from the configuration shown in FIG. 28A . The force applied from distal sheath 572 to strut 554 collapses the strut, and at the same time causes floating anchor 558 to move distally on tubular member 564 towards distal stop 560 . In FIG. 28B , floating anchor 558 has been moved distally and is engaging distal stop 560 , preventing any further distal movement of floating anchor 558 . As strut 554 is collapsed by distal sheath 572 , strut 554 will force the attachment point between strut 554 and expansion support 555 towards tubular member 564 , beginning the collapse of expansion support 555 . Distal sheath 572 continues to be advanced distally relative to the distal filter (or the distal filter is pulled proximally relative to the distal sheath, or a combination of both) until the distal filter is collapsed within distal sheath 572 , as is shown in FIG. 28C . Filter membrane 552 is bunched to some degree when the filter is in the configuration shown in FIG. 28C . To deploy the distal filter from the sheath, guiding member 566 is advanced distally relative to the distal sheath (or the distal sheath is moved proximally relative to the filter). The distal portions of filter membrane 552 and expansion support 555 are deployed first, as is shown in FIG. 28D . Tension in the filter membrane prevents wadding and binding during the deployment. When strut 554 is deployed from the distal sheath, expansion support 555 and strut 554 are able to self-expand to an at-rest configuration, as shown in FIG. 28E . Floating anchor 558 is pulled in the distal direction from the position shown in FIG. 28D to the position shown in FIG. 28E due to the expansion of strut 554 .
FIGS. 29A-29E illustrate a portion of an exemplary filter system with a lower delivery and insertion profile. In FIG. 29A , the system includes proximal sheath 604 with a larger outer diameter than distal sheath 602 . In some embodiments proximal sheath 604 has a 6 F outer diameter, while distal sheath 602 has a 5 F outer diameter. A guiding member including distal tip 606 is disposed within the distal sheath and the proximal sheath. FIG. 29B illustrates tear-away introducer 608 , with receiving opening 610 and distal end 612 . Introducer is first positioned within a subject with receiving opening 610 remaining outside the patient. As shown in FIG. 29C , the smaller diameter distal sheath is first advanced through the receiving opening of introducer 608 until the distal end of the distal sheath is disposed distal relative to the distal end of the introducer. The introducer is then split apart and removed from the subject, as shown in FIG. 29D . The filter system can then be advanced distally through the subject. The introducer can be a 5 F introducer, which reduces the insertion and delivery profile of the system.
The embodiments in FIGS. 25A-25B above illustrated some exemplary systems and methods for routing filter systems to a desired location within a subject, and additional exemplary embodiments will now be described. FIGS. 30A and 30B illustrate an exemplary embodiment similar to that which is shown in FIGS. 27A and 27B . The filter system shows distal filter 650 and proximal filter 644 in expanded configurations. Proximal sheath 642 has been retracted to allow proximal filter 644 to expand. Distal filter, which is secured to guiding member 648 , are both advanced distally relative to distal articulating sheath 640 . The filter system does not have a dedicated guidewire that is part of the system, but distal sheath 640 is adapted to be rotated and steered to guide the system to a target location within the subject.
FIGS. 31A-31C illustrate an exemplary over-the-wire routing system that includes a separate distal port for a dedicated guidewire. A portion of the system is shown in FIG. 31B , including distal articulating sheath 662 and proximal sheath 660 (the filters are collapsed therein). FIG. 31B is a highlighted view of a distal region of FIG. 31A , showing guidewire entry port 666 near the distal end 664 of distal sheath 662 . FIG. 31C is a sectional view through plane A of distal sheath 662 , showing guidewire lumen 672 , spine element 678 , distal filter lumen 674 , and steering element 676 (shown as a pull wire). Guidewire lumen 672 and distal filter lumen 674 are bi-axial along a portion of distal sheath, but in region 670 guidewire lumen 672 transitions from within the wall of distal sheath 662 to being co-axial with proximal sheath 660 .
To deliver the system partially shown in FIGS. 31A-31C , a guidewire is first delivered to a target location within the subject. The guidewire can be any type of guidewire. With the guidewire in position, the proximal end of the guidewire is loaded into guidewire entry port 666 . The filter system is then tracked over the guidewire to a desired position within the subject. Once the system is in place, the guidewire is withdrawn from the subject, or it can be left in place. The proximal and distal filters can then be deployed as described in any of the embodiments herein.
FIGS. 32A-32E illustrate an exemplary routing system which includes a rapid-exchange guidewire delivery. The system includes distal articulating sheath 680 with guidewire entry port 684 and guidewire exit port 686 . The system also includes proximal sheath 682 , a distal filter secured to a guiding member (collapsed within distal sheath 680 ), and a proximal filter (collapsed within proximal sheath 682 ). After guidewire 688 is advanced into position within the patient, the proximal end of guidewire 688 is advanced into guidewire entry port 684 . Distal sheath (along with the proximal sheath) is tracked over guidewire 688 until guidewire 688 exits distal sheath 680 at guidewire exit port 686 . Including a guidewire exit port near the entry port allows for only a portion of the guidewire to be within the sheath(s), eliminating the need to have a long segment of guidewire extending proximally from the subject's entry point. As soon as the guidewire exits the exit port, the proximal end of the guidewire and the proximal sheath can both be handled.
FIG. 32B shows guidewire 688 extending through the guidewire lumen in the distal sheath and extending proximally from exit port 686 . Guidewire 688 extends adjacent proximal sheath 682 proximal to exit port 686 . In FIG. 32B , portion 690 of proximal sheath 682 has a diameter larger than portion 692 to accommodate the proximal filter therein. Portion 692 has a smaller diameter for easier passage of the proximal sheath and guidewire. FIG. 32C shows a sectional view through plane 32 C- 32 C of FIG. 32B , with guidewire 688 exterior and adjacent to proximal sheath 682 . Proximal filter 694 is in a collapsed configuration within proximal sheath 682 , and guiding member 696 is secured to a distal filter, both of which are disposed within distal shaft 698 .
FIG. 32D shows relative cross-sections of exemplary introducer 700 , and distal sheath 680 through plane 32 D- 32 D. Distal sheath 680 includes guidewire lumen 702 and distal filter lumen 704 . In some embodiments, introducer 700 is 6 F, with an inner diameter of about 0.082 inches. In comparison, the distal sheath can have a guidewire lumen of about 0.014 inches and distal filter lumen diameter of about 0.077 inches.
FIG. 32E shows a sectional view through plane 32 E- 32 E, and also illustrates the insertion through introducer 700 . Due to the smaller diameter of portion 692 of proximal sheath 682 , guidewire 688 and proximal sheath 682 more easily fit through introducer 700 than the distal sheath and portion of the proximal sheath distal to portion 692 . The size of the introducer may vary depending on the diameter of the filter system. The introducer may range in size from 4 F to 15 F. In certain embodiments, the size of the introducer is between 4 F and 8 F. Guidewire 688 may vary in diameter between 0.005 and 0.02 inches or between 0.01 and 0.015 inches. In some situations, it may be desirable to have a guidewire smaller than 0.005 inches or larger than 0.02 inches in diameter. The smaller diameter proximal portion 692 of proximal sheath 682 allows for optimal sheath and guidewire movement with the introducer sheath. In certain aspects, it may be desirable for the cross-section of proximal filter deployment member 697 to take a non-circular shape to reduce the profile of proximal sheath 682 . Guiding member 696 and distal sheath pull wire 676 are both disposed through distal shaft 698 .
In certain embodiments, the guiding member is a core wire. Use of a core wire may be desirable to decrease the diameter of the filter system. A core wire is also flexible and able to access tortuous anatomies. The material and diameter of the guiding member may vary depending on the desired level of column strength or flexibility. In certain embodiments, the core wire may be tapered such that a distal section of the core wire has a smaller diameter than a proximal section of the core wire to increase flexibility at the distal section.
In certain clinical scenarios, it may be desirable for the guiding member to take the form of a tubular core member having a guidewire lumen running therethrough. In several embodiments, the tubular core member is a catheter shaft. The presence of the guidewire lumen allows the user to deliver the filter system to the correct position by advancing the filter system over the guidewire. A tubular core member allows the user to select an appropriate guidewire for the procedure rather than restricting the user to the wire core shaft. A guiding member having a guidewire lumen can potentially reduce the delivery profile of the filter system by not requiring separate lumens for the guiding member and the guidewire.
FIG. 33A illustrates filter system 700 having tubular core member 720 extending along an elongate axis of filter system 700 and slidably disposed through distal shaft 716 . The distal end of tubular core member 720 is positioned in a distal, atraumatic tip 740 of filter system 700 , while the proximal end of tubular core member 720 is positioned in the control handle. The proximal end of tubular core member 720 is connected to an actuation mechanism capable of advancing tubular core member 720 distally or retracting tubular core member 720 proximally with respect to distal shaft 716 . Distal filter assembly 726 may be mounted on a distal section of tubular core member 720 . Proximal filter 704 and distal filter 726 are illustrated as formed from a plurality of struts such as a woven wire or laser cut basket, however any of the polymeric membrane filters disclosed elsewhere herein may be used in filter system 700 .
In certain embodiments, tubular core member 720 defines a guidewire lumen 745 . Tubular core member 720 may have a distal guidewire entry port at the distal end of tubular core member 720 and a proximal guidewire exit port at the proximal end of tubular core member 720 . In other embodiments, the proximal guidewire port may be positioned at any position along the length of the tubular core member.
The length of tubular core member 720 may range from about 50 cm to about 300 cm. In some embodiments, the length may be less than 50 cm; while in other embodiments, the length may be greater than 300 cm. In several embodiments, the length of tubular core member 720 is between about 50 and about 150 cm, between about 75 and about 125 cm, or between about 100 cm and about 150 cm. The inner diameter of tubular core member 720 may range from about 0.01 to about 0.075 cm. In other embodiments, the inner diameter of tubular core member 720 is less than 0.01 cm; while in still other embodiments, the inner diameter is greater than 0.075 cm. The outer diameter of tubular core member 720 may range from about 0.025 to about 0.1 cm. In certain embodiments, the outer diameter of tubular core member 720 is less than 0.025 cm; while in other embodiments, the inner diameter is greater than 0.1 cm.
In certain clinical scenarios, it may be desirable to increase the column strength of tubular core member 720 , thus improving support and pushability to aid advancement of distal filter assembly 726 out of distal sheath 718 . In certain scenarios, tubular core member 720 may be constructed from a material stiffer than the material from which distal shaft 716 is constructed. A stiffer tubular core member 720 can help improve the column strength of filter system 700 . The tubular core member 720 may be constructed from metallic materials such as stainless steel, Nitinol, cobalt chromium (MP35N), or other alloys used in medical devices. Alternatively, tubular core member 720 may be constructed from a polymer construction such as nylon, polyester, polypropylene, polyimide, or other polymers exhibiting similar properties. In some embodiments, tubular core member 720 may be constructed from a combination of metallic materials and polymeric materials. In some embodiments, the inner diameter of tubular core member 720 is either coated with or constructed of a lubricious polymer (e.g. HDPE, PTFE, FEP, etc.). In still other embodiments, tubular core member may include reinforcements. For example, a ribbon or other stiffening member may extend along a section of tubular core member 720 . Alternatively, tubular core member 720 may have a multi-lumen profile, a first lumen for a guidewire and a second lumen for a stiffening mandrel. Tubular core member 720 may also transition from a multi-lumen profile to a single lumen profile to increase flexibility along the single lumen section of the tubular core member. In still other embodiments, tubular core member 720 may include one or more longitudinal strands dispersed within the tubular core member shaft to improve tensile strength. In some embodiments, tubular core member 720 may have a braided or coiled shaft to increase column strength. In certain embodiments, the braid consists of both metallic and polymer materials. In other embodiments, the braid consists of only metal; while in still other embodiments, the braid consists of only polymer materials.
In other clinical scenarios, it may be desirable to provide more flexibility in certain sections or along the entire length of tubular core member 720 . When filter system 700 is deployed in a curved lumen, a rigid tubular core member 720 or other guiding member may pull the leading portion 732 of distal filter 736 away from the vessel wall if the distal region of tubular core member 720 or other guiding member lacks sufficient flexibility to deflect relative to filter system 700 in a tortuous anatomy.
In certain embodiments, tubular core member 720 may be constructed from a more flexible material. In other embodiments, a first portion of tubular core member 720 may be constructed from a flexible material, while a second portion of tubular core member 720 is constructed from a stiffer material. Alternatively, removal of portions of tubular core member 720 may provide greater flexibility along certain sections of tubular core member 720 . For example, a series of slots, cuts, or a spiral pattern may be cut into a section of tubular core member 720 to provide a flex zone having a greater flexibility than proximal and distal adjacent portions of tubular core member 720 . The pattern of cuts may vary along the tubular core member shaft to vary flexibility along tubular core member 720 . The flexible portion may alternatively comprise a coil, helix, or interrupted helix. In other embodiments, a first portion of the tubular core member may also have a thinner wall than a second portion of the tubular core member. In still other embodiments, tubular core member 720 may be tapered to increase stiffness along a first section of the tubular core member and increase flexibility along a second section of the tubular core member.
In certain embodiments, a distal section of tubular core member 720 may be more flexible than a proximal section of the tubular core member 720 using any of the methods discussed above. The length of the flexible distal section may measure from about 5 cm to about 50 cm, from about 10 to about 40 cm, or from about 15 to about 25 cm. In other embodiments, the flexible distal section may be less than 5 cm or greater than 50 cm.
Several embodiments may include a flexible coupler 722 to allow distal filter assembly 726 to deflect relative to the rest of filter system 700 . In several embodiments, tubular core member 720 includes a flexible coupler 722 positioned proximal to distal filter assembly 726 . In several embodiments, flexible coupler 722 defines a lumen through which a guidewire may pass. In some embodiments, flexible coupler 722 is spliced into a gap along tubular core member 720 . In some embodiments, tubular core member 720 may comprise a distal tubular core member and a proximal tubular core member. The distal end of the proximal tubular core member may be joined to the proximal end of flexible coupler 722 , while the proximal end of the distal tubular core member is joined to the distal end of flexible coupler 722 . In still other embodiments, tubular core member 720 and flexible coupler 722 are integrally formed such as by providing core member 720 with a plurality of transverse slots as is described elsewhere herein.
In some clinical scenarios, it may be desirable for flexible coupler 722 to be more flexible than tubular core member 720 , while still demonstrating properties strong enough to resist deformation under tensile loads. Flexible coupler 722 may be constructed from materials, such as polymers, multiple polymers, Nitinol, stainless steel, etc. In certain embodiments, flexible coupler 722 may be created by piercing, slotting, grooving, scoring, cutting, laser cutting or otherwise removing material from a tubular body to increase flexibility. Alternatively, a flexible coupler 722 may be integrally formed with tubular core member 720 using any of the above mentioned patterns. In another embodiment, flexible coupler 722 is created by thinning a portion of tubular core member 720 to create a more flexible region. Flexible coupler 722 may also be deformed into a serrated or bellows shape without removing any material from the tubular body. Any of the other methods discussed above to increase the flexibility of tubular core member 720 may also be applied.
In some embodiments, a flexible section 738 of tubular core member 722 may be configured to be more flexible than a proximal section of tubular core member 722 . In some aspects, flexible section 738 is positioned distal to flexible coupler 722 . The length of flexible section 738 may measure from about 5 mm to about 50 mm, from about 10 to about 30 mm, or from about 20 to about 40 mm. In other embodiments, the flexible distal section may be less than 5 mm or greater than 50 mm.
FIGS. 33B-D illustrate cross sections at various positions along the dual filter system depicted in FIG. 33A . FIG. 33B illustrates a cross section of filter system 700 , proximal to proximal filter assembly 704 . Guidewire 721 is disposed through a lumen defined by tubular core member 720 , and tubular core member 720 is disposed through a lumen defined by distal shaft 716 . In certain embodiments, at least a portion of distal sheath 718 may be articulated via pull wire 737 . FIG. 33B shows that at least a portion of pull wire 737 may be disposed through distal shaft 716 , but external to tubular core member 720 . In some embodiments, at least a portion of pull wire 737 may pass through a lumen embedded in at least a portion of the distal shaft wall or distal sheath wall. In FIG. 33B , a portion of distal shaft 716 may be disposed through a lumen defined by proximal shaft 701 . Proximal filter frame 714 may extend through a lumen embedded in at least a portion of the proximal filter shaft wall 701 . Proximal filter shaft 701 is disposed through a lumen defined by proximal sheath 702 .
FIG. 33C depicts a cross section distal to the cross section depicted in FIG. 33B through distal sheath 718 . Distal sheath is illustrated in a simplified form, but typically will include all of the deflection mechanisms of FIGS. 9A-9E , discussed above. FIG. 33C shows guidewire 721 disposed through a lumen defined by tubular core member 720 . At least a portion of tubular core member 720 is disposed through a lumen defined by distal sheath 718 . As depicted in 33 C, at least a portion of distal sheath 718 may be provided with a reinforcement such as an embedded coil or braid 719 to improve torquing capabilities. In some embodiments, the entire length of distal sheath 718 may comprise a reinforcing element such as a braid. Pull wire 737 may extend through a lumen extending through at least a portion of the distal sheath 718 , and distal sheath spinal element 741 may extend through at least a portion of distal sheath 718 . In some embodiments, the outer diameter of distal sheath 718 is substantially similar to the outer diameter of proximal sheath 702 . In other embodiments, distal sheath 718 extends through a lumen defined by proximal sheath 702 .
FIG. 33D depicts a cross section distal to the cross-section depicted in FIG. 33C . FIG. 33D shows guidewire 721 disposed through a lumen defined by tubular core member 720 . Tubular core member 720 is coaxial with flexible coupler 722 . In certain embodiments, the diameter of flexible coupler 722 may be larger than the diameter of tubular core member 720 . In other embodiments, flexible coupler 722 may have the same diameter as tubular core member 720 . In still other embodiments, the diameter of flexible coupler 722 may be smaller than the diameter of tubular core member 720 . In certain embodiments, the flexible coupler may not be a separate component.
As shown in FIGS. 34A-C , a tubular core member 720 coupled with a flexible coupler 722 has the advantage of providing improved column strength along a substantial length of the filter system 700 , but providing the flexibility necessary for distal filter assembly 726 to position itself independent of the position of distal shaft 716 . Flexible coupler 722 allows distal filter frame element 728 to create a better seal against the vessel wall to help prevent embolic debris from flowing between distal filter 736 and the vessel wall.
A filter system having a flexible coupler 722 is deployed similarly to the method described in FIGS. 2A-2D . In one embodiment, as distal sheath 718 is advanced into the left common carotid artery, tubular core member 720 is advanced distally relative to distal sheath 718 . FIG. 34B illustrates filter system 700 after tubular core member 720 is advanced into the left common carotid artery. Distal filter 736 expands and flexible coupler 722 deflects relative to filter system 700 such that distal filter frame element 728 is circumferentially apposed to the vessel wall. Strut 724 may be proximally retracted as desired to tilt the frame element 728 to improve the fit of the distal filter 736 within the vessel.
In certain embodiments, the stiffness of tubular core member 720 may be further reduced during use by the operator by withdrawing the guidewire until the distal end of the guidewire is proximal to flexible coupler 722 such that the guidewire is no longer disposed within flexible coupler 722 , thus reducing stiffness.
FIGS. 35A-B illustrate a tubular body 750 suitable for use as a flexible coupler 722 . A tubular body 750 having a proximal end 754 and a distal end 756 may be formed by wrapping a ribbon or wire around a mandrel or by laser cutting a tube with a spiral pattern to form a coil. The width of spaced regions 752 a,b between each adjacent coil loop 751 may be different in an unstressed orientation depending on the desired properties. In some embodiments, it may be desirable to provide greater flexibility, in which case, spaced region 752 b should be wider to allow for a greater range of movement. In certain clinical scenarios, it may be desirable to provide smaller spaced regions 752 a between each coil portion 751 to help prevent a first edge 753 a and a second edge 753 b of each coil portion 751 from dislodging plaque from the vessel wall or damaging the vessel wall. In an alternate embodiment, a flexible coupler 722 having wider spaced regions 752 a between each coil portion 751 may be covered by a thin sheath such as shrink wrap tubing to provide flexibility and protect the vessel wall from flexible coupler 722 .
In FIG. 35C , a tubular body 760 having a proximal end 764 and a distal end 766 is laser cut with a plurality of slots 762 , each slot 762 having a first end 768 a and a second end 768 b . In some embodiments, two or more slots 762 form a circumferential ring 771 around flexible coupler 722 . In several embodiments, a plurality of circumferential rings 771 is laser cut into a tubular body 760 . The plurality of circumferential rings 771 may be staggered such that a first slot of a first circumferential ring is misaligned from a first slot of a second circumferential ring. The plurality of slots 762 are configured such that flexible coupler 722 flexes angularly while retaining good torque resistance and tensile displacement resistance.
FIG. 35D depicts a flexible coupler 722 constructed from a tubular body 770 having a proximal end 774 and a distal end 776 . Tubular body 770 is laser cut with a spiral pattern, the spiral pattern having a plurality of interlocking ring portions, wherein a first interlocking ring portion 778 a interlocks with a complementary second interlocking ring portion 778 b . Flexible coupler 722 has an interlocking pattern designed to resist axial deformation (stretching) when placed in tension. FIG. 35E illustrates flexible coupler 722 also having interlocking ring portions 778 . In this embodiment, an axial element 784 is positioned across an interlocking feature 782 to improve the axial stiffness of flexible coupler 722 when subject to tensile loading.
Although the above mentioned embodiments were discussed in connection with a tubular core member, the same properties may be applied to any other guiding member. The guiding member may incorporate any of the above mentioned properties alone, or in combination, to manipulate flexibility and column strength along the guiding member shaft. The embodiments may also be used in connection with the proximal filter or any other catheter-based system.
In certain clinical scenarios, it may be desirable for the filter opening to circumferentially appose the vessel wall. This helps prevent debris from flowing past the filter. In a straight lumen, a filter can achieve good apposition with the vessel wall, thus preventing plaque or blood clots from flowing past the filter when it is deployed in a vessel. In contrast, when a filter is deployed in a curved lumen, the filter frame element can settle into a number of different rotational orientations in the lumen. In some clinical scenarios, when the filter is deployed in a curved lumen, it is possible for the filter frame element to pull away from the vessel wall particularly on the inner radius thus leading to poor apposition and blood leakage past the filter.
In current settings, practitioners may seek to overcome this poor positioning by using contrast injections and fluoroscopic imaging in one or more views. The filter is then either re-sheathed and redeployed or rotated or repositioned without re-sheathing, a process that can dislodge plaque from the vessel wall or otherwise damage the vessel. Neither of these solutions is satisfactory due to the extended procedure time and the increased possibility of vessel damage due to increased device manipulation.
In certain scenarios, it may be advantageous to add a tethering member to a filter assembly. FIGS. 36A-E illustrate tethering member 842 attached to proximal filter assembly 804 . Tethering member 842 is configured to draw proximal filter frame element 814 closer to the vessel wall in order to form a seal with the inner surface of the vessel. Proper apposition of proximal filter assembly 804 relative to the vessel wall prevents debris from flowing past proximal filter assembly 804 . This can be achieved with a flexible tethering member (e.g. monofilament polymer, braided polymer, suture, wire, etc.) or with a rigid or semi-rigid member such as nitinol, thermoplastic, stainless steel, etc.
Tethering member 842 has a first end 844 and a second end 846 . In FIG. 36A , the first end 844 of tethering member 842 is affixed to proximal sheath 802 , while the second end 846 of tethering member 842 is affixed to proximal filter assembly 804 . In some embodiments, tethering member 842 is affixed to filter frame element 814 ; while in other embodiments, tethering member 842 is affixed to proximal filter 806 . FIGS. 36B-C illustrate how tethering member 842 laterally deflects the frame 814 and pulls filter frame element 814 toward the vessel wall when the operator retracts proximal sheath 802 . Proximally retracting tethering member 842 allows the operator to control the deflection and angle of proximal filter frame element 814 . In other embodiments, tethering member 842 can be actuated passively rather than actively (i.e. by the operator) by forming tethering member 842 from an elastic material or spring in order to elastically pull the edge of proximal filter frame element 814 toward the vessel wall.
In still other embodiments, the second end 846 of tethering member 842 may be attached to a feature disposed along proximal filter 806 . For example, in FIG. 36E , the second end 846 of tethering member 842 is connected to a rib 848 formed on proximal filter 806 . In still other embodiments, the first end 844 of tethering member 842 may be attached to an elongate member such as a pull wire slidably disposed along the length of the catheter system to a control actuator in the control handle. This allows the operator to control the deflection of proximal filter frame element 814 independently from proximal sheath 802 .
In certain embodiments, it may be preferable to attach a distal end of tethering member 842 to a single location on proximal filter assembly 804 . Alternatively, as shown in FIG. 36D , it may be preferable to attach the distal end of tethering member 842 to two or more positions on proximal filter assembly 804 .
In order to facilitate sheathing and to minimize tangling when proximal filter assembly 804 is collapsed into proximal sheath 802 , tethering member 842 may be twisted to form a coil 849 , as shown in FIG. 37A . Twisted portion 849 retracts and stays out of the way when proximal filter assembly 804 is sheathed, and twisted portion 849 will untwist and straighten as the operator deploys proximal filter assembly 804 . The design is also helpful for controlling the slack in tethering member 842 during sheathing and unsheathing. Tethering member 842 may be formed from a heat deformable polymer and applying heat to deform the polymer into a twisted configuration. Tethering member may alternatively be formed from nitinol or any other material having suitable properties. In other embodiments, it may be preferable for tethering member 842 to form a coil ( FIG. 37B ), pre-formed to particular shapes ( FIG. 37C ), or have two or more tethering members ( FIG. 37D ). One or more tethering members may be formed into any other design that may decrease the likelihood that tethering member 842 will become tangled with other catheters or devices.
Although the previously discussed tethering members have been discussed in connection with proximal filter assemblies, a tethering member may be used in connection with a distal filter, other filter devices, or any intraluminal device that may desirably be laterally displaced, tilted or otherwise manipulated into a desired orientation, such as to improve alignment including improving apposition with a vessel wall.
In some clinical scenarios, it may be desirable to place a single filter in a blood vessel. Any of the above mentioned features of the dual filter embodiments may be applied to the single filter embodiments described below, including, but not limited to, filter design, sheath articulation, or guiding member flexibility or column strength. In addition, filter systems described herein can be utilized in connection with a variety of intravascular interventions. The embodiments described below will be discussed in connection with a TAVI procedure, but the filter systems may be used with other intravascular or surgical interventions such as balloon valvuloplasty, coronary artery bypass grafting, surgical valve replacement, etc. and should not be construed as limited to the TAVI procedure.
In certain situations, it may be desirable to position the filter in the aorta, distal to the aortic valve but proximal to the brachiocephalic artery ostium, such that the entire arterial blood supply can be filtered. The aortic filter may also be positioned in the aorta, between the right brachiocephalic artery ostium and the left carotid artery ostium. In other scenarios, the aortic filter may be positioned between the left carotid artery ostium and the left subclavian artery ostium, while in still other clinical situations may make it preferable to position the aortic filter in the descending aorta, distal to the left subclavian artery ostium. In some cases, an aortic filter can be positioned in the aorta in combination with brachiocephalic and left carotid artery filters in order to capture all embolic debris.
An aortic filter can be positioned at various locations along a catheter system. In one embodiment, the aortic filter can be positioned on a catheter separate from the TAVI or pigtail catheter and inserted through the left or right brachial artery or the right or left femoral artery. Using a separate aortic filter catheter decreases the overall diameter of the TAVI catheter and allows the operator to position the aortic filter independently from aortic valve. Further, the aortic filter will not dislodge plaque along the vessel wall when the TAVI catheter is repositioned or rotated.
In another embodiment, the aortic filter can be positioned on the TAVI catheter shaft, proximal to the valve prosthesis. To decrease the size of the overall catheter system, the diameter of the TAVI catheter system proximal to the valve prosthesis may be reduced in size. This embodiment decreases the number of total devices in the operating environment, thus decreasing the likelihood that devices will get tangled.
In yet another embodiment, the aortic filter may be positioned on the TAVI introducer. This embodiment enables the operator to position the aortic filter independently from the position of the TAVI catheter. The filter is also less likely to dislodge plaque along the vessel wall when the TAVI catheter is repositioned or rotated. Introducing the aortic filter on the TAVI introducer also decreases the total number of catheters into the operating environment.
In still another embodiment, the aortic filter is positioned on a pigtail catheter shaft, proximal to the pigtail. Affixing the aortic filter to the pigtail catheter does not increase the overall diameter of the TAVI system or add any additional catheters into the operating environment.
In one embodiment, the aortic filter is positioned on an extended pigtail introducer sheath. This embodiment enables the operator to position the aortic filter separately from the location of the pigtail without adding any additional catheters into the operating environment. Positioning the aortic filter on the pigtail introducer sheath also does not increase the overall diameter of the TAVI system. Further, the aortic filter will not dislodge plaque along the vessel while when the pigtail and/or TAVI catheter is repositioned or rotated.
Various methods can be used to perform a TAVI procedure in connection with an aortic filter. In one method, the aortic filter is positioned as early as possible in the procedure at any location in the aorta previously described, and the aortic filter may be deployed using any of the above mentioned devices. The TAVI catheter may then be inserted through the filter and the TAVI implantation is performed. Afterward, the TAVI catheter and aortic filter are removed.
In an alternative method, a guidewire is positioned through the aorta and the pigtail catheter is inserted into the aorta. A TAVI catheter can then be advanced to a position just proximal of where the aortic filter will be deployed. The aortic filter may be deployed at any position described above. Using any of the previously discussed embodiments, a catheter carrying an aortic filter deploys an aortic filter in the aorta. The aortic filter also forms a seal against both the TAVI catheter and the vessel wall such that debris cannot flow past the filter. After the aortic filter is deployed, the TAVI catheter is advanced to the implant location and the implant procedure is performed. When the procedure is over, the TAVI catheter is withdrawn just proximal to the filter such that the operator can retrieve the aortic filter. The aortic filter, TAVI, and pigtail catheters are then all withdrawn from the operating environment. These steps are not limited to the order in which they were disclosed. For example, the TAVI catheter may be advanced to the implant location before the aortic filter is deployed.
FIG. 38A depicts a TAVI catheter 933 that is deployed across an aortic filter assembly 904 in the aorta 999 . In some scenarios, aortic filter assembly 904 may not fully appose the TAVI catheter shaft, thus leaving room for debris to flow between the TAVI catheter 933 and the vessel wall. In these scenarios, it may be preferential to configure aortic filter assembly 904 to appose TAVI catheter 933 and prevent substantially all debris from flowing past aortic filter assembly 904 without significantly degrading filter capture performance. It may also be preferential to modify aortic filter assembly 904 in scenarios where TAVI catheter 933 passes through aortic filter assembly 904 .
FIG. 38B illustrates an aortic filter assembly 904 designed to pass over a guidewire 907 or other guiding member. Aortic filter assembly 904 may have a channel 909 on the exterior surface of aortic filter assembly 904 . Channel 909 is constructed such that a TAVI deployment catheter or other catheter may pass through channel 909 . The operator may also rotate aortic filter assembly 904 such that the TAVI catheter properly passes through channel 909 . The control handle may indicate the rotational location of channel 909 help the operator correctly orient aortic filter 904 . Alternatively, channel 909 may have at least one or two radiopaque markers to enable identification of channel 909 using fluoroscopy.
FIG. 38C depicts aortic filter assembly 904 having a leading edge 911 and a trailing edge 913 . Aortic filter assembly 904 passes over a guidewire 907 or other guiding member. Leading edge 911 overlaps trailing edge 913 to form an overlapping portion 935 . The control handle may indicate the location of overlapping portion 935 so the operator can torque aortic filter assembly 904 to position overlapping portion 935 over the TAVI or other catheter shaft. Overlapping portion 935 may have a radiopaque marker to allow the operator to monitor aortic filter placement under fluoroscopy.
FIG. 38D depicts an aortic filter assembly 904 designed to pass over a guidewire 907 or other guiding member. Aortic filter 904 has a first filter portion 915 and a second filter portion 917 , second filter portion 917 having a first edge 917 a , and a second edge 917 b . The first edge 917 a and the second edge 917 b of second filter portion 917 overlap first filter portion 915 to form a joint 914 . The control handle may indicate the location of joint 914 so the operator can torque aortic filter assembly 904 to position joint 914 against the shaft of the TAVI catheter. As the operator advances a catheter-based device across aortic filter 904 , second filter portion 917 caves inward such that joint 914 forms a seal around the catheter shaft. Aortic filter assembly 904 may include a radiopaque marker to allow the operator to identify joint 914 under fluoroscopy.
FIGS. 39 A-C depict an aortic filter device having two or three or four or more aortic lobes or filters. Each aortic filter lobe 904 a,b,c is joined together along a first side 919 of each aortic filter lobe 904 a,b,c . Aortic filter lobes 904 a,b,c join together about a longitudinal axis of the aortic filter system. The aortic filter system is configured such that a TAVI catheter 933 or other catheter-based device may pass between a first aortic filter assembly 904 b and a second aortic filter assembly 904 c . The first and second aortic filters 904 b,c forming a seal around the TAVI catheter 933 , thus preventing debris from flowing past the aortic filter system.
FIG. 40A depicts generally conical aortic filter assembly 904 resembling an umbrella. Aortic filter 904 may pass over a guidewire 907 or other guiding member. Aortic filter assembly 904 has a plurality of self-expanding tines 923 , each tine having a proximal end and a distal end. Each tine joins together at a first end 903 of aortic filter assembly 904 . In addition, a filter portion 925 is suspended between tines 923 . Filter portion 925 may be fairly inflexible or flexible to stretch over the TAVI catheter 933 or other catheter-based device. When an operator advances TAVI catheter 933 past aortic filter assembly 904 , TAVI catheter 933 passes between a first tine 923 and a second tine 923 such that a filter portion 925 stretches over TAVI catheter 933 to form a seal between filter portion 925 and TAVI catheter 933 .
Alternatively, FIG. 40B depicts an aortic filter assembly 904 resembling a flower. In one embodiment, aortic filter assembly 904 has two or more petals 943 arranged in a circular array that allow TAVI catheter 933 or other catheter-based device to pass between petals 943 . Petals 943 may overlap one another to create a seal between adjacent petals 943 . Petals 943 also create a seal around TAVI catheter 933 as the catheter passes between petals 943 . The shape of each petal 943 may include an arch to better accommodate the circular shape of the aorta. Each petal 943 may have a length between two to six centimeters. Although in some embodiments, the length may be less than in two centimeters; while in still other embodiments, the length may be greater than six centimeters. In one embodiment, the individual petals are comprised of a frame 944 that is covered with a filter element 945 . The frame 944 may be constructed of a shape memory material such as Nitinol, or other material such as stainless steel, cobalt supper alloy (MP35N for example) that has suitable material properties. The filter element 945 may be constructed of a polyurethane sheet that has been pierced or laser drilled with holes of a suitable size. Other polymers may also be used to form the filter element, in the form of a perforated sheet or woven or braided membranes. Thin membranes or woven filament filter elements may alternatively comprise metal or metal alloys, such as nitinol, stainless steel, etc.
Any of the aortic filter assemblies described above may also include frame element 914 formed from a material suitable to form a tight seal between aortic filter assembly 904 and TAVI catheter 933 or other catheter-based device as the filters fill under systolic blood pressure.
FIGS. 41A-B depicts an aortic filter assembly 904 having an inflatable portion 927 defining a distal opening 912 of aortic filter 906 . In some embodiments, inflatable portion 927 forms a continuous ring. Inflatable portion 927 forms a seal against the vessel wall such that debris cannot pass between aortic filter assembly 904 and the vessel wall. Inflatable portion 927 may also form a seal against a TAVI catheter passed between aortic filter assembly 904 and the vessel wall.
As depicted in FIG. 41A , inflatable portion 927 and filter element 906 may form a channel 929 on an exterior surface of aortic filter assembly 904 through which a catheter-based device may pass. Channel 929 forms a seal against the catheter such that debris may not flow between the aortic filter assembly 904 and the catheter.
FIG. 41B illustrates an inflatable portion 927 having a gap 931 through which a catheter-based device may pass. Filter element 906 may also form a channel on the exterior surface of the aortic filter assembly 904 through which the catheter may pass.
In an embodiment which includes an inflatable annulus or other support, the inflatable support is placed in fluid communication with a source of inflation media by way of an inflation lumen extending throughout the longitudinal length of the catheter shaft. Once the filter has been positioned at a desired site, the annulus can be inflated by injection of any of a variety of inflation media, such as saline. The inflation media may thereafter be aspirated from the filter support, to enable collapse and withdraw of the filter. The inflation media may include a radiopaque dye to help the operator locate the inflatable annulus under fluoroscopy.
Although the filter systems described above were discussed in connection with a single filter system, the filter designs may also be used in connection with a dual filter system.
FIG. 42 depicts one embodiment of a filter assembly that may be used in connection with any filter-based device, including the dual filter and single filter systems described above. Filter assembly 926 may comprise a filter membrane 936 , a filter frame element 928 , and at least one radiopaque marker. Filter membrane may 936 may be constructed from a polyurethane film or any other polymer or material exhibiting suitable properties. In some embodiments, a laser or other mechanism may be used to create at least one filter hole in the filter membrane through which blood may flow. The at least one filter hole is small enough such that a blood clot or piece of embolic debris exceeding a predetermined dimension cannot pass through. The filter membrane may be formed into a conical or other shape by heat sealing a first edge of the filter membrane to a second edge of the filter membrane, although other methods may be used to join a first edge of the filter membrane to a second edge of the filter membrane. In several embodiments, filter assembly 926 may also include flexible coupler 922 .
A frame element 928 may be shaped from a Nitinol wire, but, as discussed in earlier paragraphs, the frame element may be shaped from any other suitable material or textured to exhibit desired properties. In some embodiments, at least one radiopaque marker is incorporated into filter assembly 926 . In one embodiment, a 90/10 platinum/iridium coil marker is positioned around frame element 928 and bonded with an adhesive. Alternatively, other types of radiopaque markers may be integrated into or affixed to frame element 928 . Other methods of affixing the radiopaque marker may also be used.
In several embodiments, filter assembly 926 includes a strut tubing 924 . Strut tubing 924 may be constructed from PET heat shrink tube, polyimide tube, or any other material exhibiting suitable properties. In one embodiment, strut tubing 924 is affixed to one or more legs of frame element 928 with an adhesive, although other means for affixation may also be used. Additional mechanisms may also be used to reinforce the adhesive or other means of affixation. Alternatively, strut tube 924 may be slipped over one or more portions of the frame element 928 and may additionally be bonded in place.
In some embodiments, filter membrane 936 may be attached to frame element 928 by heat-sealing a first portion of filter membrane 936 to a second portion of filter membrane 936 to form a sleeve through which frame element 928 may pass. An adhesive may be used to reinforce the bond between the frame element and the filter membrane. Other mechanisms may also be used to affix frame element 928 to filter membrane 936 . Additional mechanisms may also be used to reinforce the adhesive or other affixation mechanism.
In some embodiments, frame element 928 is attached to a filter shaft 920 via a stainless steel crimp 998 , although other mechanisms may be used to affix frame element 928 to a filter shaft 920 . Additional affixation methods may also be used to reinforce the stainless steel crimp 998 or other mechanism.
In several embodiments, a cannulated distal tip 940 having an atraumatic distal end with a guidewire exit port is joined to the distal end of filter shaft 920 .
FIG. 43 illustrates a proximal portion of an exemplary filter system. The portion shown in FIG. 43 is generally the portion of the system that remains external to the subject and is used to control the delivery and actuation of system components. Proximal sheath 1010 is fixedly coupled to proximal sheath hub 1012 , which when advanced distally will sheath the proximal filter (as described herein), and when retracted proximally will allow the proximal filter to expand. The actuation, or control, portion also includes handle 1016 , which is secured to proximal shaft 1014 . When handle 1016 is maintained axially in position, the position of the proximal filter is axially maintained. The actuation portion also includes distal sheath actuator 1022 , which includes handle 1023 and deflection control 1020 . Distal sheath actuator 1022 is secured to distal shaft 1018 . As described herein, the distal articulating sheath is adapted to have three independent degrees of motion relative to the proximal sheath and proximal filter: rotation, axially translation (i.e., proximal and distal), and deflection, and distal sheath actuator 1022 is adapted to move distal sheath 1018 in the three degrees of motion. Distal sheath 1018 is rotated in the direction shown in FIG. 43 by rotating distal sheath actuator 1022 . Axial translation of distal sheath occurs by advancing actuator 1022 distally (pushing) or by retracting actuator 1022 proximally (pulling). Distal sheath 218 is deflected by axial movement of deflection control 1020 . Movement of deflection control 1020 actuates the pull wire(s) within distal sheath 1018 to control the bending of distal sheath 1018 . Also shown is guiding member 1024 , which is secured to the distal filter and is axially movable relative to the distal sheath to deploy and collapse the distal filter as described herein. The control portion also includes hemostasis valves 1026 , which in this embodiment are rotating.
FIG. 44 illustrates an exemplary 2-piece handle design that can be used with any of the filter systems described herein. This 2-piece handle design includes distal sheath actuator 1046 , which includes handle section 1048 and deflection control knob 1050 . Deflection control knob 1050 of distal sheath actuator 1046 is secured to distal shaft 1054 . Axial movement of distal sheath actuator 1046 will translate distal shaft 1054 either distally or proximally relative to the proximal filter and proximal sheath. A pull wire (not shown in FIG. 44 ) is secured to handle section 1048 and to the distal articulatable sheath (not shown in FIG. 44 ). Axial movement of deflection control knob 1050 applies tension, or relieves tension depending on the direction of axial movement of deflection control knob 1050 , to control the deflection of the distal articulatable sheath relative to the proximal filter and proximal sheath 1044 , which has been described herein. Rotation of distal sheath actuator 1046 will rotate the distal sheath relative to the proximal filter and proximal sheath. The handle also includes housing 1040 , in which proximal sheath hub 1042 is disposed. Proximal sheath hub 1042 is secured to proximal sheath 1044 and is adapted to be moved axially to control the axial movement of proximal sheath 1044 .
FIG. 45 illustrates another exemplary embodiment of a handle that can be used with any of the filter systems described herein. In this alternate embodiment the handle is of a 3-piece design. This 3-piece handle design comprises a first proximal piece which includes distal sheath actuator 1061 , which includes handle section 1063 and deflection control knob 1065 . Deflection control knob 1065 of distal sheath actuator 1061 is secured to distal shaft 1067 . Axial movement of distal sheath actuator 1061 will translate distal shaft 1067 either distally or proximally relative to the proximal filter and proximal sheath. A pull wire (not shown in FIG. 45 ) is secured to handle section 1063 and to the distal articulatable sheath (not shown in FIG. 45 ). Axial movement of deflection control knob 1065 applies tension, or relieves tension depending on the direction of axial movement of deflection control knob 1065 , to control the deflection of the distal articulatable sheath relative to the proximal filter and proximal sheath 1069 . Rotation of distal sheath actuator 1061 will rotate the distal sheath relative to the proximal filter and proximal sheath 1069 . The handle design further includes a second piece comprising central section 1060 which is secured to proximal shaft 1071 . A third distal piece of this handle design includes housing 1062 . Housing 1062 is secured to proximal sheath 1069 . Housing 1062 is adapted to move axially with respect to central section 1060 . With central section 1060 held fixed in position, axial movement of housing 1062 translates to axial movement of proximal sheath 1069 relative to proximal shaft 1071 . In this manner, proximal filter 1073 is either released from the confines of proximal sheath 1069 into expandable engagement within the vessel or, depending on direction of movement of housing 1062 , is collapsed back into proximal sheath 1069 .
FIG. 46 depicts another embodiment of a control handle. The control handle has a proximal filter control 1100 and a distal filter control 1102 . To deploy the device, the distal shaft of the catheter is fed over a guidewire and manipulated into position in the patient's anatomy. To deploy the proximal filter, the proximal filter sheath control 1120 is withdrawn proximally while holding the proximal filter handle 1118 stationary. The proximal filter sheath control 1120 is a sliding control; however, any other control such as a rotating knob, a pivoting lever, etc. may be used to withdraw the sheath.
When the proximal filter is properly deployed, the distal filter contained in the distal sheath is advanced distally and positioned in the target location by advancing the distal filter control 1102 while holding the proximal filter control 1100 stationary. During this positioning process, the distal filter control 1102 can be advanced, retracted or rotated relative to the proximal filter control 1100 , and as needed, the deflection of the distal sheath may be controlled by actuating the distal sheath deflection control 1112 relative to the distal filter sheath handle 1110 . The distal sheath deflection control 1112 is a pivoting control; however, any other control such as a rotating knob, a sliding knob, etc. may be used to deflect the sheath. Once the sheath containing the collapsed distal filter is positioned correctly, the position of the distal filter control 1102 is locked relative to the proximal filter control 1100 by tightening the proximal handle hemostasis valve 1116 . Next, the distal filter may be deployed by advancing the guiding member 1108 by grasping the distal filter Luer fitting 1104 until the filter is deployed. The position and orientation of the distal filter may be adjusted by advancing, retracting or rotating the distal filter Luer fitting 1104 relative to the distal filter sheath handle 1110 . Finally, the position of the distal filter may be fixed relative to the distal filter sheath handle 1110 by tightening the distal handle hemostasis valve 1106 . To remove the device upon completion of the procedure, the aforementioned procedure is reversed.
FIGS. 47A through 47I illustrate cross-sections through the control handle illustrated in FIG. 46 , taken along the section lines indicated in FIG. 46 .
FIGS. 47A-B depict cross-sectional areas of proximal filter control 1100 . The distal shaft 1108 is disposed through a lumen defined by the articulating distal sheath 1114 . In these figures, the articulating distal sheath 1114 is disposed through a lumen defined by the proximal filter shaft 1124 , and the proximal filter shaft is disposed through a lumen defined by the front handle 1118 .
FIG. 47C depicts a cross-sectional area of a distal section of distal filter control 1102 . In FIG. 47C , articulating distal sheath 1114 is disposed through a lumen defined by the rear handle 1110 as shown in FIG. 47C . FIG. 47D shows a cross-sectional view proximal to the cross-section shown in FIG. 47C . In FIG. 47D , guiding member 1108 is disposed through a lumen defined by the rear handle 1110 . Guiding member 1108 defines a lumen 1128 through which a guidewire may pass. FIG. 47E shows a cross-sectional view proximal to the cross-section shown in FIG. 47D . The guiding member 1108 is coaxial with a stainless steel hypotube 1130 . Hypotube 1130 reinforces the guiding member 1108 .
FIG. 47F depicts a longitudinal cross-section of proximal filter control 1100 . At the distal end of proximal filter control 1100 , there is a nose piece 1132 holding the front handle 1118 together. Proximal to nose piece 1132 there is a proximal filter sheath control 1120 to actuate the proximal filter sheath and deploy the proximal filter. The proximal filter sheath control is associated with a locking mechanism 1126 to prevent unintentional filter deployment and to actuate a sealing mechanism to prevent blood leakage. The locking mechanism 1126 comprises a locking element 1134 , an elastomeric seal 1138 , a spring 1136 , and a nut 1140 for holding locking mechanism 1126 together. In certain embodiments, squeezing the proximal filter sheath control 1120 will release the locking element 1134 between the proximal sheath 1122 and proximal filter shaft 1124 .
FIGS. 47G-H depicts a longitudinal cross section of distal filter control 1102 . At a distal section of the distal filter control 1102 , there is a mechanism to actuate articulating distal sheath 1114 . The actuation mechanism includes an axially movable deflection lever 1112 pivoting on distal sheath pivot 1146 . The distal sheath deflection lever 1112 is connected to the distal sheath pull wire at attachment point 1150 . The pull wire is disposed through channel 1148 . Proximal to rear handle 1110 there is a distal handle hemostasis valve 1106 . Distal handle hemostasis valve 1106 comprises elastomeric seal 1152 and HV nut 1154 . Distal filter shaft 1108 and hypotube 1130 extend proximally from distal filter control 1102 and terminate at distal filter luer lock fitting 1104 .
An alternative control handle uses a rotating screw drive mechanism to deflect a distal end of a distal articulating sheath is shown in FIG. 48 . In certain clinical scenarios, it may be desirable to include a mechanism that prevents the articulating sheath from unintentionally deflecting when the operator releases the handle. The mechanism incorporates a lead screw 1214 which is inherently self-locking in that tip deflection will be locked wherever the handle control is released by the operator. A rotating screw drive mechanism provides an easy to manufacture design to control the pivot of the articulating sheath. The rate of deflection of the tip is controlled by the pitch of the screw threads 1218 , thus rapid deflection of the tip, which can lead to unintentional vessel damage, can be prevented.
While specific embodiments have been described herein, it will be obvious to those skilled in the art that such embodiments are provided by way of example only. Numerous variations, changes, and substitutions will now occur to those skilled in the art without departing from that which is disclosed. It should be understood that various alternatives to the embodiments described herein may be employed in practicing the disclosure. | Single filter and multi-filter endolumenal methods and systems for filtering fluids within the body. In some embodiments a blood filtering system captures and removes particulates dislodged or generated during a surgical procedure and circulating in a patient's vasculature. In some embodiments a filter system protects the cerebral vasculature during a cardiac valve repair or replacement procedure. | 0 |
TECHNICAL FIELD
Embodiments are generally related to sensor systems and devices. Embodiments are also related to oil filters utilized in internal combustion engines. Embodiments are additionally related to techniques for monitoring oil usage and quality and reducing the frequency of oil changes thereof.
BACKGROUND OF THE INVENTION
A typical oil change for modern cars or light trucks includes both draining the oil and replacing the filter every 3,000 to 7,000 miles. It is estimated in the U.S., alone, that over 1 billion gallons of engine oil annually are changed in the passenger car/light truck segment every year. An additional 250 Million gallons of oil are consumed in the commercial truck market segment.
There is a growing need to minimize the flow of unregulated waste oil in the environment. Extending the useful life of engine lubricating oil can significantly reduce contamination of the air and ground water (through evaporation and landfill seepage, respectively). Also, a reduction in engine oil consumption can help to lessen our dependence on foreign oil.
Modern cars, trucks and other transportation vehicles are designed for unprecedented life and reduced maintenance. Fewer components associated with the car/truck require regular replacement. For example, spark plugs and engine coolant now last 100,000 miles or more. Exhaust systems last the life of the vehicle. The chassis no longer requires lubrication. As a result, the ongoing cost of vehicle ownership is going down. This trend will continue. The reduced cost of vehicle ownership is especially important in the heavy-duty truck and off-highway market segments. Initial vehicle investment, reliability, and vehicle up time all contribute to company profitability. Therefore, reduced maintenance costs and more vehicle time on the road are very attractive to a fleet management company. In summary, extended oil change intervals are good for both profitability and the environment.
BRIEF SUMMARY OF THE INVENTION
The following summary is provided to facilitate an understanding of some of the innovative features unique to the embodiments and is not intended to be a full description. A full appreciation of the various aspects of the embodiments can be gained by taking the entire specification, claims, drawings, and abstract as a whole.
It is, therefore, one aspect of the embodiments to provide for improved sensing systems and devices.
It is another aspect of the embodiments to provide for an oil management system utilized in internal combustion engines.
It is a further aspect of the embodiments to provide a system for monitoring oil quality and oil filter effectiveness thus reducing the frequency of oil changes thereof.
The aforementioned aspects and other objectives and advantages can now be achieved as described herein. An oil management system is disclosed, which includes an oil filter utilized in association with an internal combustion engine. The oil filter comprises filtration media for filtering engine oil associated with the internal combustion engine. One or more types of time-release additives can be impregnated into the filtration media. The time release additives are automatically released into the engine oil filter from the filtration media in order to replenish additives already present in the engine oil.
Additionally, a sensor module can be provided that communicates with the oil filter and detects one or more attributes of the engine oil filtered through the filtration media of oil filter in order to efficiently conserve and manage the oil and reduce the interval of oil changes thereof by extending the life of the engine oil through the replenishment of the additives present in the engine oil. A housing (e.g., canister) can be provided for maintaining the oil filter. The sensor module is located preferably, but not exclusively within the oil filter housing. The sensor module can continuously or periodically monitor the oil in order to measure multiple parameters of oil quality and/or oil filter condition. The filter can be configured from high efficiency filtration media, such as, for example, nano-fiber based filtration media. Power to the sensor module can be capacitive or wired.
Additionally, a wireless module can be associated with and in communication with the sensor module to permit sensor data compiled by the sensor module to be transmitted wirelessly to a receiver. A monitoring device can be utilized, which monitors data transmitted wirelessly from the sensor module. The monitoring device is associated with the receiver and comprises a memory for maintaining the data transmitted wirelessly from the sensor module. Additionally, a GPS device can be associated with and/or integrated with the monitoring device, wherein the GPS device permits the data stored within the memory of the monitoring device to be polled or up-linked.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying figures, in which like reference numerals refer to identical or functionally-similar elements throughout the separate views and which are incorporated in and form a part of the specification, further illustrate the present invention and, together with the detailed description of the invention, serve to explain the principles of the present invention.
FIG. 1 illustrates an exploded view of an example oil filter apparatus that can be adapted for use in accordance with an embodiment;
FIG. 2( a ) illustrates a side view of the oil filter apparatus depicted in FIG. 1 ;
FIG. 2( b ) illustrates a general pictorial diagram illustrating the flow of oil filtration and an oil filter basket arrangement, which may be implemented in accordance with the oil filter apparatus depicted in FIGS. 1 and 2( a );
FIG. 3 illustrates pictorial diagram of an oil management system that can be implemented in accordance with one embodiment;
FIG. 4 illustrates a high-level block diagram of an oil management system that can be implemented in accordance with another embodiment;
FIG. 5 illustrates a block diagram illustrating additional components of the system depicted in FIG. 4 ;
FIG. 6 illustrates a side view of an oil sensing system that can be implemented in accordance with an alternative embodiment;
FIG. 7 illustrates a block diagram of an oil management system that can be implemented in accordance with an alternative embodiment; and
FIG. 8 illustrates a side view of an oil sensing system that can be implemented in accordance with an alternative embodiment.
DETAILED DESCRIPTION OF THE INVENTION
The particular values and configurations discussed in these non-limiting examples can be varied and are cited merely to illustrate at least one embodiment and are not intended to limit the scope thereof.
FIG. 1 illustrates an exploded view of an example oil filter apparatus 10 that can be adapted for use in accordance with an embodiment. Note that the oil filter apparatus 10 depicted in FIG. 1 is described herein for illustrative purposes only and is not considered a limiting feature of the embodiments. Instead, oil filter apparatus 10 is provided in order to depict the context in which one embodiment can be implemented. The embodiment of FIG. 1 is therefore provided for exemplary and edification purposes only and may be modified or varied, depending upon design considerations. The embodiments disclosed herein can be implemented in the context of a wide variety of automotive systems, such as, for example, heavy duty trucks, tractor trailers, conventional automobiles, and so forth.
The example oil filter apparatus 10 depicted in FIG. 1 can incorporate a housing 12 , which may be formed as a steel filter body covered, for example, by an epoxy powder paint. An oil filter 16 can be provided in the form of a filter cartridge. Oil filter 16 is generally composed of filtration media 14 , which can be implemented, for example, in the form of pleated filter media. The filtration media 14 is preferably implemented as high-efficiency filtration media (i.e., filtration media that is at least 95% efficient at 5 microns and above).
Oil filter 16 is maintained within housing 12 below a retainer 20 and a relief valve 22 . A center tube 18 is centrally located within oil filter 16 . End disks 8 and 10 can also be provided to provide additional strength and stability to oil filter 16 within housing 12 . An anti-drain valve 6 can be located below oil filter 16 and adjacent to a tapping plate 4 formed from a bottom assembly 2 and located immediately above a bottom portion 24 . An external gasket 26 can be configured below bottom assembly 2 .
FIG. 2( a ) illustrates a side view of the oil filter apparatus 10 depicted in FIG. 1 . FIG. 2( b ), on the other hand, illustrates a general pictorial diagram illustrating the flow of oil filtration and an alternative oil filter basket arrangement, which may be implemented in accordance with the oil filter apparatus depicted in FIGS. 1 and 2( a ). Note that in FIGS. 1 , 2 ( a ) and 2 ( b ), identical or similar parts or elements are generally indicated by identical reference numerals. Thus, oil filter 16 with filtration media 14 is depicted in FIG. 2( a ).
In FIG. 2( a ), arrow 26 indicates that oil filter 16 can be located and maintained within oil filter apparatus 10 . In FIG. 2( b ), an alternative embodiment is disclosed. Oil filter 16 can be modified for placement within a basket 42 and housed within an oil filter apparatus 40 that includes elements that were depicted in FIG. 1 . Arrow 51 indicates the placement of basket 42 within oil filter apparatus 40 . Arrows 44 , 46 , 49 , and 50 indicate the general flow of filtered oil in association with the functioning of oil filter 16 . Arrows 56 , 54 , and 52 generally indicate the flow of additized oil within oil filter apparatus 40 . Note that oil filter apparatus 40 depicted in FIG. 2( b ) represents a modified implementation of oil filter apparatus 10 depicted in FIGS. 1-2( a ).
FIG. 3 illustrates pictorial diagram of an oil management system 300 that can be implemented in accordance with one embodiment. System 300 generally includes an oil filter container or housing 302 that maintains oil filter 303 that contains filtration media 304 , which can be implemented as high-efficiency filtration media. For example filtration media 304 can be configured as nano-fiber based filtration media that possess the ability to filter particles at the sub-micron level. Thus such nano-fiber based filtration media addresses two problems. First, such media prevents soot agglomeration that leads to sludge build-up. Second, such media reduces acid built-up created by combination of high soot levels and water (e.g., inherent in diesel fuel). Filtration media 304 depicted in FIG. 3 is therefore analogous to the high-efficiency filtration media 14 depicted in FIGS. 1-2( a ).
Oil filter 303 can be implemented in the context of an oil filter assembly or mechanism such as, for example, oil filter apparatus 10 depicted in FIG. 1-2 . System 300 also incorporates the use of additives 306 . As indicated by arrow 307 , additives 306 can be impregnated into filtration media 304 and housed in a standard replacement oil filter canister or housing 302 . A sensor module 308 can be embedded in the canister or housing 302 . Sensor module 308 generally detects key oil condition attributes associated with oil maintained or filtered by oil filter 303 .
In some implementations of the embodiments, additives 306 can be configured as time-release additives. It is important to note, however, that additive(s) 306 are not restricted to time-release or are necessarily impregnated into the filtration media. The additive(s) 306 can also be released based on need or simply released with no logic involved. The additive can be in the form of a gel, pellets, solid disks, etc. The additive can be presented to the oil similar to that shown in FIG. 2( b ) herein with respect to arrows 56 , 54 , 52 . In the particular embodiment depicted in FIG. 2( b ) with respect to basket 42 , the additive flows by a gel in the basket 42 on the clean side of the filter media thereof.
FIG. 4 illustrates a high-level block diagram of an oil management system 400 that can be implemented in accordance with another embodiment. Note that in FIGS. 3-5 herein, identical or similar parts or elements are generally indicated by identical reference numerals. System 400 indicates that canister 302 can maintain sensor module 308 , additives 306 and oil filter 303 . Sensor module 308 can monitor oil filter 302 and identify and detect additives 306 , depending upon design considerations.
It is important to note that the depletion of additives 306 can be anticipated. A solid mixture of additive chemistry can dissolve at a rate based on oil flow, time and temperature. The oil additive concentration levels are maintained throughout the oil filter 303 change intervals. The combination of very high-efficiency filtration (e.g., filtration media implemented via nano-fiber base filtration media) and stable additive concentration levels throughout the filter service interval precludes the need to change the oil in the sump. As indicated previously, such high-efficiency filtration media is preferably filtration media that is at least 95% efficient at 5 microns and above.
Depending on oil operating temperatures, small amounts of base oil oxidation may occur. A build up of oxidized oil can eventually result in sludge and reduced lubrication properties. In conventional systems, oxidized oil is removed when the oil is changed. According to the embodiments disclosed herein, however, if the oil filter 303 selectively removes oxidized oil, there is a reduced need to change the oil.
There are external variables that can adversely affect oil quality. With the oil change interval being extended by as much as an order of magnitude, according to the embodiments, it is also desirable to monitor oil quality. With appropriate sensors to monitor oil PH etch rate, metal contamination, pressure, temperature, soot loading in filter, and/or the presence of coolant or fuel, additional protection can be provided to systems 300 , 400 . The oil quality information can be displayed or up-linked on a real time basis utilizing monitoring device 414 disclosed in FIGS. 4 and 5 .
A wireless module 402 can be connected to sensor module 308 in order to transmit data wirelessly from sensor module 308 through antenna 404 , which is incorporated with wireless module 402 . Power 406 to sensor module 308 can be provided as capacitive 408 or wired 410 , depending upon design considerations. Sensor data can therefore be transmitted from wireless module 402 to a receiver 412 associated with an antenna 415 . Wireless communications are represented in FIG. 4 by dashed line 407 . A monitoring device 414 is associated with receiver 412 . Both the monitoring device 414 and the receiver 412 may be located within a vehicle cabin (e.g., a car, heavy duty truck, etc.). The monitoring device 414 thus monitors data transmitted wirelessly from the sensor module 308 .
FIG. 5 illustrates a block diagram illustrating additional components of the system 400 depicted in FIG. 4 . In FIG. 5 , sensor module 308 and monitoring device 414 are depicted in greater detail. Sensor module 308 can incorporate a memory unit 502 for storing data collected by sensor module 308 . Similarly, monitoring device 414 can include a memory 408 for storing data transmitted to it wirelessly (e.g., data transmitted as indicated by arrow 407 in FIG. 4 ).
Monitoring device 414 may also incorporate a Global Positioning System (GPS) device 510 . Data stored in memory 508 has the capability of being polled or up-linked utilizing GPS techniques. Note that as utilized herein, the term Global Positioning System (GPS) generally refers to the worldwide radio-navigation system that uses the position of satellites to determine locations on the earth. The GPS is formed generally from a group or constellation of orbiting man-made satellites and their respective ground station, thereby utilizing such satellites as reference points to calculate accurate positions. Monitoring device 414 can also be associated with a management module 512 that collects sensor data input and allows for historical analysis of the oil quality data, allowing for accurate maintenance scheduling and productivity analysis for engine fleet owners. Management module 512 can be implemented as a software module, which is defined and described in greater detail herein.
FIG. 6 illustrates a side view of an oil sensing system 600 that can be implemented in accordance with an alternative embodiment. Note that in FIGS. 1-8 , identical or similar parts or elements are generally indicated by identical reference numerals. Thus, systems 300 - 400 depicted herein can be modified in accordance with the configuration depicted in systems 600 - 700 as described herein. System 600 generally includes a housing or canister 302 in which filter 303 (i.e., having filter media 304 ) is located. Sensor module 308 can be implemented in the context of system 600 as a sensor probe with multiple transducers 611 , 613 , 615 . A power component 406 can be implemented as a circuit board with a power supply, signal conditioning components thereof, and wireless input/output capabilities such as that of wireless module 402 and antenna 404 depicted in FIG. 4 . Engine oil can flow through a central cavity 617 which is surrounded by filter 303 and filter media 304 thereof.
System 600 can also be equipped with a bypass filter 605 , which can bypass, for example, approximately, 6%-10% of the total engine oil flow. A plurality of TBN pellets 609 can also be provided above the filter 303 . Note that filter 303 can be configured with filter media 304 (not shown in FIG. 6 ) that filters, for example, approximately 90%-94% of total engine oil flow, depending upon design considerations and goals. Sensor module 308 can therefore indicate oil conditions, such as, for example, soot, alkalinity TBN, and so forth, thereby preventing the need to actually send the oil out to a third party or location for testing.
FIG. 7 illustrates a block diagram of an oil management system 700 that can be implemented in accordance with an alternative embodiment. System 700 incorporates the sensing system 600 depicted in FIG. 6 , such that data can be transmitted wirelessly as indicated by wireless transmissions 407 , 721 , and 726 depicted in FIG. 7 . Data can be transmitted from system 600 to a receiver (e.g., receiver 412 ) located in a heavy-duty truck 720 . Data from the truck 720 can then be transmitted to an antenna 722 and related via a GPS component 510 to a user 728 for further analysis and evaluation.
FIG. 8 illustrates a side view of an oil sensing system 800 that can be implemented in accordance with an alternative embodiment. Again, it is important to note that in FIGS. 1-8 , identical or similar parts or elements are generally indicated by identical reference numerals. System 800 is similar to that of system 600 and incorporates filter media 304 and additionally, an indentation 801 in the existing filter canister 302 .
In general, the embodiments, such as systems 300 - 800 can result in the ability to extend oil change intervals through the use of an effective removal of combustion products and replenishments of oil additives (i.e., helps to protect lubricity, reduce corrosion and keep the engine clean). This demand is met through the use of high performance/selective filtration media 304 and through the use of an effective additive replenishment strategy. Depending on their size, soot particle can be captured by filter media 304 . Smaller particles remain suspended in the oil.
The engine oil itself can be designed to suspend sub-micron soot particles. If soot concentrations are too high, however, the oil filter 303 can make up the difference. Extending the life of engine oil requires the capture of small soot particles. Also, oil additives are replaced on a timely basis. The base oil goes through very little, if any, degradation. As oil additives are depleted, systems 300 - 800 can “intelligently” refresh the oil with new additives. “Smart” filtering, along with additive replenishment, combines to extend the useful life of engine oil. It is conceivable that that the use of systems 300 - 800 , for example, can increase oil life by a factor in a range of, for example, 4-10.
Based on the foregoing it can be appreciated that the combination of oxidized oil and soot removal, additive replenishment (e.g., on a regular basis), and real-time oil quality monitoring can successfully preclude the need for regular oil changes and the unnecessary discarding of millions of gallons of perfectly fine base oil. Such an advantage not only reduces the cost of vehicle ownership, but is also beneficial for the environment.
Note that the term “module” as utilized herein can refer to a physical hardware component (i.e., a hardware module), a software component (e.g., a software module) or a combination thereof. A software module can therefore be implemented as one or more instruction modules residing in a computer memory, such as, for example, memory units 508 and/or 502 . the computer programming arts, a “module” can be typically implemented as a collection of routines and data structures that performs particular tasks or implements a particular abstract data type.
Software modules generally are composed of two parts. First, a software module may list the constants, data types, variable, routines and the like that can be accessed by other modules or routines. Second, a software module can be configured as an implementation, which can be private (i.e., accessible perhaps only to the module), and that contains the source code that actually implements the routines or subroutines upon which the module is based. Thus, for example, the term module, as utilized herein generally refers to software modules or implementations thereof. Such modules can be utilized separately or together to form a program product that can be implemented through signal-bearing media, such as, for example, transmission media and/or recordable media.
Thus, sensor module 308 can be composed of a hardware component (e.g., a sensor) and/or a software component. Similarly, wireless module 402 can also be composed of a hardware component (e.g., a wireless transmitter/receiver) and/or a software component. Management module 512 depicted in FIG. 5 , which is associated with monitoring module 414 , is preferably implemented as a software module that can be stored in a computer memory of a data-processing system and processed utilizing a microprocessor.
It will be appreciated that variations of the above-disclosed and other features and functions, or alternatives thereof, may be desirably combined into many other different systems or applications. Also that various presently unforeseen or unanticipated alternatives, modifications, variations or improvements therein may be subsequently made by those skilled in the art which are also intended to be encompassed by the following claims. | An oil management system and oil filter utilized in association with an internal combustion engine. The oil filter comprises high-efficiency filtration media for filtering engine oil associated with the internal combustion engine. At least one type of time release additive can be impregnated into the filtration media, wherein the time release additives are automatically released into the engine oil filter from filtration media in order to replenish additives already present in the engine oil. Additionally, a sensor module can be provided that monitors oil quality and oil filter efficiency through detecting one or more attributes of the engine oil filtered through the filtration media of oil filter in order to efficiently conserve and manage the oil and reduce the interval of oil changes thereof by extending the life of the engine oil through the replenishment of the additives present in the engine oil and higher filtration effectiveness of the filter. | 1 |
The Government has rights to this invention pursuant to Contract No. F30602-81-C-0189 awarded by the Department of the Air Force.
This application is a continuation of application Ser. No. 538,238, filed Oct. 3, 1983 (now abandoned).
FIELD OF THE INVENTION
This invention relates to optical wavelength division multiplexing or demultiplexing couplers and, more particularly, to such couplers of the diffraction grating type.
BACKGROUND OF THE INVENTION
Diffraction grating couplers used as optical multiplexing or demultiplexing devices take light from the input fiber or fibers, respectively, and couple it back into output fibers or fiber, respectively. These couplers utilize a diffraction grating, that is, an angularly dispersive device, that diffracts away incident collimated light at an angle dependent upon the incidence angle and the wavelength of the incident light. In this way, light can be separated by wavelength and coupled as desired.
There are several types of diffraction grating couplers, one common type using a concave diffraction grating and another common type using a radially graded refractive index (hereafter GRIN) lens with a plane diffraction grating. The concave diffraction grating type device has the advantage of not requiring any light collimating and/or refocusing optics. Its disadvantages are that extremely tight control must be exercised in forming the spherical concave surface and also in forming the grating configuration. Compounding the latter requirement is the fact that the ruling tool used to form the grating must swing through an arc as it traverses the spherical surface. In addition, concave grating type devices have a low diffraction efficiency and can suffer from image astigmatism. The disadvantage of the GRIN lens type device is that it includes an additional optical device to collimate and focus the light.
SUMMARY OF THE INVENTION
This invention overcomes the disadvantages of the two types of diffraction grating couplers noted above by providing a diffraction grating type coupler comprising an elongated optical component formed of light transmitting material. One end of the optical component is formed with a convex surface coated with a reflecting material and a portion of the other end is formed with a diffraction grating which is also coated with a reflecting material. Another portion of the other end is formed so as to receive a fiber array. The shape of the convex surface is such that the path of the light from the convex surface to any fiber in the array is equal to about one focal length.
BRIEF DESCRIPTION OF THE DRAWINGS
For a better understanding of the invention, reference is made to the following description of a preferred embodiment thereof, taken in conjunction with the figures of the accompanying drawing, in which:
FIG. 1 is a perspective view of a diffraction grating coupler in accordance with this invention;
FIG. 2 is a schematic illustration of a diffraction grating coupler in accordance with this invention; and
FIG. 3 is a schematic illustration of another diffraction grating in accordance with this invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In FIG. 1 there is illustrated a diffraction grating coupler 10 and a multiple fiber array 12. In this embodiment the coupler 10 is functioning as a multiplexer and, thus, the multiple fiber array includes a plurality of fibers (in this embodiment, eight such fibers) 14a, b, c, d, e, f, g and h, each connected to a light source (not shown), for example, a laser or a light emitting diode. It should be understood that any number of fibers can be included in the array. Each light source provides light at a different wavelength. The light from each fiber is the incident light and is combined by the coupler 10 and coupled into an output or link fiber 16 connected into a fiber optics system. It should be understood that if the coupler 10 is functioning as a demultiplexer, the incident light would include all of the wavelengths and would be transmitted along the fiber 16 to the coupler which would distribute each wavelength to its appropriate fiber 14a through 14h. In this mode, each of the fibers 14a through 14h would be connected to a suitable light detector, for example, an avalanche photodiode or a PIN diode.
In FIGS. 1 and 2, the coupler 10 can be seen to include an elongated optical component 18 formed of a good light transmitting material. In this embodiment the light transmitting material is glass and is preferably, pure fused silica. Any of various materials can be used and should have a generally uniform index of refraction. As shown in FIG. 1, the optical component 18 has a generally rectangular cross-section, but other shapes are usable.
As also shown in FIG. 1, the component 18 is actually two blocks of pure fused silica 18a and 18b having generally planar mating surfaces in abutting relationship. The blocks 18a and 18b are fixed together to form a unitary component. Conveniently the blocks 18a and 18b are fixed together by a good optical grade epoxy 20, i.e., an epoxy that transmits light. The use of two blocks of silica is preferred in some instances since it facilitates the making of coupler 10 as will be clear from later descriptions of the invention. It should be understood that a single block of material could be used as illustrated in FIG. 2 or 3.
One end of the elongated optical component 18 is formed with a convex surface 22 coated with a light reflecting material. Gold or silver are preferred materials coated on the surface 22 and this surface can be formed by any conventional technique. The preferred configuration for surface 22 is spherical where the radius of curvature is such that light emitted from the fiber array into the component 18 travels a path to the surface 22 having a length equal to about one focal length of the light reflecting surface. In this way, the light is collimated by the spherical surface 22. In some cases it may be desirable to have the configuration of surface 22 an aspherical surface, that is, a surface defined by more than one equation in order to minimize aberration. Thus, the term spherical as used herein should be construed to include an aspherical surface.
The other end of the optical component is formed with a generally planar surface 24, one portion of which is formed with a diffraction grating 26. It should be understood that the diffraction grating is a large number of grooves as shown in FIG. 2 of the drawing. It should also be understood that the size of the grooves is greatly exaggerated in FIG. 2 for the sake of clarity. The diffraction grating 26 is also coated with a light reflecting material such as gold or silver. The remaining portion of the planar surface 24 is that portion to which the multiple fiber array 12 is secured. This can also be accomplished by the use of a suitable optical grade epoxy.
The diffraction grating 26 can be formed on the planar end surface 24 by a conventional ruling tool, usually a diamond blade. The diffraction grating can also be formed on a wedge which is epoxied to the planar surface of block 18b with an optical epoxy 20, as shown in FIG. 1. It is preferred, however, to replicate the grating 26 on the end face 24. Replication can be accomplished by coating the one portion of the planar surface 24 with a suitable optical grade resin and pressing a master die having the diffraction grating pattern on its contact surface into the resin while it is still soft enough to form. Thereafter, the resin is cured and coated with the reflecting material in accord with conventional techniques. The use of two blocks 18a and 18b is preferred when the diffraction grating 26 is replicated because handling of the material is facilitated.
Various resins can be used and should have an index of refraction when cured, approximately equal to that of the light transmitting material. Suitable resins are made by Bausch and Lomb, Microscopy and Image Analysis Division, located in Rochester, N.Y.
With reference to FIG. 2, it can be seen that incident light traveling the optical component 10 until it strikes the mirrored spherical surface 22 where it is collimated and reflected through the component to the diffraction grating 26. When the collimated light strikes the diffraction grating 26 it is diffracted back to the mirrored spherical surface 22 where it is reflected and focused into an output fiber.
As shown in FIG. 2, the convex spherical surface 22 is centered with respect to the optical axis A of the component 18. With the surface 22 so centered the planar surface 24 forms an angle T with a line perpendicular to the optical axis. Angle T is approximately equal to one-half the grating incidence angle required for efficient grating operation. In some embodiments, as shown in FIG. 3, it may be desirable to have the planar surface perpendicular to the optical axis of the component. Such a perpendicular surface is shown at 24a in the component 18a. In these embodiments the convex spherical surface 22a should be off-center so that it, in effect, inclines the surface 24 to an effective angle equal to one-half the incidence angle required for efficient grating operation.
The outer surfaces of the component 18, excluding surfaces 22 and 24, may have a ground glass finish to decrease internal scattering from the convex surface 22 and from the diffraction grating 26. The ground glass finished surfaces may be blackened or otherwise treated to enhance their light trapping ability.
While in the foregoing there has been described preferred embodiments of the invention, it should be understood that various changes and modifications can be made without departing from the spirit and scope of the invention. | A wavelength division multiplexing or demultiplexing optical coupler of the diffraction grating type includes a pure fused silica optical element having a convex spherical surface on one end and a diffraction grating on a portion of its other end. The remaining portion of its other end receives a multiple fiber array for transmitting and receiving the light to be multiplexed or demultiplexed. | 6 |
DESCRIPTION
ORIGIN OF THE INVENTION
The invention described herein was made by an employee of the United States Government and may be manufactured or used by or for the Government without the payment of any royalties thereon or therefor.
TECHNICAL FIELD
This invention relates to printing plates and is directed more particularly to a plate for printing images comprises of two or more colors.
One method of printing multicolor images involves printing each color separately. This method is quite expensive and time consuming because a separate plate is needed for each color and, except for rotary presses, a separate printing run must be made for each color.
Flat multicolor printing plates are known and generally comprise a lower plate and an upper plate with a plastic gasket between them. In such plates a pattern of the image to be printed is formed in the paper-contacting surface of the lower plate and each separate part of the pattern receives ink from ink distribution channels in the upper plate. The ink distribution channels in the upper plate have the same general outline as the various parts of the pattern in the lower plate and the gasket has the same pattern as the ink distribution channels.
In making this type of multicolor printing plate, the gasket is pressed between the upper and lower plates while the plates are heated. The result often is that the plastic melts and expands into the various ink distribution channels in other openings so that ink is not properly distributed in the lower plate.
BACKGROUND ART
U.S. Pat. No. 2,514,469 to Burkhardt discloses a heat exchanger which includes one pre-formed metal plate with a plurality of corrugations or deformed areas into which pressurized water is injected to clean solder from existing passageways. A series flow passageway is established between superimposed sheet metal portions as a result of the bonding material being applied in a particular pattern to one of the sheet metal portions. Other areas of the sheets are plated with copper or zinc and covered with chromium to prevent them from being bonded.
U.S. Pat. No. 2,421,607 to Fowler discloses a method of making a metallic printing screen by laminating a solder coated screen and solder coated plate under pressure while the solder is plastic.
U.S. Pat. No. 4,021,901 to Kleine et al discloses a method for manufacturing a heat exchanger from metal sheets having a weld inhibiting material applied to one of the sheets. The sheets are clamped together and pressure-welded and hot-dashed rolled. The portions which do not weld together because of the weld-inhibiting material are then inflated by introducing air or water to form a system of internal tubular passageways.
U.S. Pat. No. 3,394,446 to Valyi discloses the method of forming a composite metal structure which includes a weld-inhibiting material. Because of the weld-inhibiting material, a pattern of passageways may be formed by the injection of fluid into areas in which welding was inhibited.
U.S. Pat. No. 3,483,616 to Shomphe discloses a method for forming a printed circuit board. An insulating board having conductor patterns on both sides and eyelet connector holes between the patterns is coated with a protected coating and then passed through a soldering machine. Solder is applied on the unprotected areas of the conductor pattern.
U.S. Pat. No. 3,048,916 to Gahlinger discloses a method of making welded passageway panels. A weld-resist pattern is printed on one-half of a metal sheet which is then folded over and subjected to high temperature and pressure. The unwelded area is then pressure-expanded to form passageways.
DISCLOSURE OF THE INVENTION
In accordance with the invention patterns corresponding to the various colors of an image to be printed are formed in the paper contacting surface of a printing plate. Each individual color pattern has a plurality of apertures extending through to the back surface of the printing plate.
A backup plate to be fused to the printing plate has ink distribution channels formed therein with each ink distribution channel including a port which extends through to the back of the backup plate and to which appropriate tubes supplying colored ink are connected. The ink distribution channels may, but need not, correspond to the exact size and shape of the respective pattern parts in the printing plate, the requirement being that ink distribution channels each encompasses all of the apertures extending through the printing plate from the various pattern parts.
To make a complete printing plate, the ink flow channels of the backup plate are coated with a solder mask material which can be removed by a liquid. A layer of solder is then applied to the backup plate and the backup plate is positioned against the printing plate. While the plates are under pressure they are heated sufficiently to make the solder plastic and allowed to cool. The plates are now fused together without blockage of any of the ink distribution channels or the ink flow apertures. The solder mask material is removed by forcing a suitable solvent through the ink flow apertures, channels and ports.
BRIEF DESCRIPTION OF THE DRAWING
The single FIGURE of the drawing shows the printing plate and backup plate used to make a multicolor printing plate in accordance with the invention and also shows the prior art gasket used between the plates.
BEST MODE FOR CARRYING OUT THE INVENTION
Referring now to the single FIGURE, the printing plate 10 and a backup plate 11, the two main components of a multicolor printing plate made in accordance with the invention, are shown. As viewed in the FIGURE the bottom or paper contacting surface of plate 10 has a pattern of a multicolored image as, for example, a multiblade, high efficiency propeller formed therein. The propeller pattern on the bottom surface of plate 10 comprises a hub 11 corresponding to a first color, inner blades 12 corresponding to a second color, blade stripes 13 corresponding to a third color and blade tips 14 corresponding to a fourth color. The various parts of the pattern are formed by engraving, etching or the like. An alternative method involves providing the pattern in a suitable form material over which the plate 10 may be cast.
Each of the pattern parts 11 through 14 is provided with one or more apertures extending through plate 10 to its top surface. The number, size and distributions of these apertures is dependent on the ink viscosity and pressure, as is known to those skilled in the art.
The backup plate 11 is provided with ink flow channels 111 through 114 corresponding to the pattern parts 11 through 14 of printing plate 10. Although the ink flow channels 111 through 114 are similar in size and shape to the corresponding pattern parts 11 through 14, this is not a requirement. It is only necessary that each of the ink flow channels 111 through 114 encompass all of the apertures of a corresponding part of the pattern parts 11-14 in the printing plate 10.
Ink input ports 211 through 214 extend from respective ones of the ink flow channels 111 through 114 through to the top surface of backup plate 11. Inks of first, second, third and fourth colors are supplied to ink input ports 211 through 214 as required by the first, second, third and fourth colors to be printed by the pattern on plate 10.
In the single FIGURE there is shown a gasket 20 which is typical of the prior art. The gasket 20 of the prior art was generally a plastic material pressed between the plates 10 and 11 binding them together. The gasket 20 is not used with the method and apparatus of the instant invention.
According to the instant invention the ink channels 11 through 114 of backup plate 11 are coated with a material to which solder will not adhere. Such materials are well known in the art of printed circuit board manufacture where they are referred to as solder mask materials.
The solder mask material used to coat the ink channels 111 through 114 should be of the type which is soluble in some liquid to facilitate its removal after 10 and 11 are bonded together as will be described presently. Preferably, a water soluble mask material is used and is applied to the ink channels 111 through 114 by means of an appropriately sized brush.
Prior to fusing the printing plate 10 and the backup plate 11 into a unitary assembly, a coating of solder is applied to the bottom surface of the plate 11. Preferably, this is accomplished by wave soldering techniques used for making printed circuit boards. This technique involves passing the bottom surface of the plate 11 rapidly over a standing wave created in a mass of molten solder.
In order to fuse plates 10 and 11 together, the solder surface or bottom surface of plate 11 is placed against the top surface of plate 10 and the plates are pressed together by a suitable means such as a clamp so that the mutual contacting surfaces of plates 10 and 11 are under a pressure of from about 1 to about 5 pounds per square inch with about 2 pounds per square inch being the preferred pressure. While the plates are being pressed together, they are heated to a temperature of about 450° F. although a temperature range of from about 295° F. to about 750° F. is acceptable.
It will be understood that different type solders have different melting temperatures and that once the melting is reached the plates may be allowed to cool to room temperature after which the pressure applied to the plates is removed. With plates 10 and 11 now fused together, the liquid soluble solder mask previously applied to the inflow channels 111 through 114 of backup plate 11 must now be removed. This is accomplished by directing through the apertures in the bottom surface of plate 10 or through the ink input ports 211-214 a liquid which will dissolve the solder mask material.
In accordance with the present invention the preferred solder mask is water soluble and, therefore, the liquid injected through the ink input ports or through the apertures in the pattern on the bottom surface of plate 10 is water. The water has a temperature in the range of from 60° F. to 180° F. The higher temperatures will increase the rapidity with which the solder mask is removed.
To remove any water trapped in the ink flow passages, ports or aperture compressed air may be injected into the ink flow ports 211 through 214 in the backup plate 11 and/or through the apertures in the bottom surface of plate 10. Additionally, or as an alternative, the multicolor printing plate made in accordance with the invention may be heated in a suitable furnace or oven to dry any remaining solder mask solvent.
The plates 10 and 11 are preferably copper. However, other materials such as aluminum may be used. Some materials such as aluminum do require extra work in preparation as well as necessitating special solders and soldering fluxes.
It will be understood that changes and modifications may be made to the foregoing described invention by those skilled in the art to which the invention pertains without departing from the spirit and scope of the invention as set forth in the claims appended hereto. | The object of the invention is to join or fuse an upper plate having ink flow channels and a lower plate having a multicolored pattern, the joining being accomplished without clogging any ink flow paths.
A pattern having different colored parts (11-14) and apertures is formed in a lower plate (10). Ink flow channels (111-114) each having respective ink input ports (211-214) are formed in an upper plate (11).
The ink flow channels (111-114) are coated with solder mask and the bottom of the upper plate (11) is then coated with solder. The upper and lower plates are pressed together at from 2 to 5 psi and heated to a temperature of from 295° F. to 750° F. or enough to melt the solder.
After the plates (10,11) have cooled and the pressure has been released, the solder mask is removed from the interior passageways by means of a liquid solvent. | 1 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is related to a provisional application entitled WELLBORE CASING U.S. Ser. No. 60/111,293, filed Dec. 7, 1998, and having Robert L. Cook, David Brisco, Bruce Stewart, Lev Ring, Richard Haut and Bob Mack as inventors thereof, and to a provisional application entitled ISOLATION OF SUBTERRANEAN ZONES U.S. Ser. No. 60/108,558, filed Nov. 16, 1998, and having Robert L. Cook as an inventor thereof, the disclosure of each of these applications being incorporated herein by this reference.
BACKGROUND OF THE INVENTION
The present invention relates generally to operations performed in conjunction with subterranean wells and, in an embodiment described herein, more particularly provides an improved expandable well screen for use in such operations.
It is well known in the art to convey a well screen into a subterranean well in a radially reduced configuration and then, after the screen has been appropriately positioned within the well, to radially expand the screen. Such expandable screens are beneficial where it is desired to position the screen below a restriction in the well, such as a restriction due to damaged casing, variations in open hole wellbore diameter, the need to pass the screen through a relatively small diameter tubular string before placing the screen in operation in a larger diameter tubular string or open hole, etc.
Presently available expandable well screens are constructed of multiple circumferentially distributed screen segments overlying an expandable inner tubular member. An outer shroud protects the screen segments against damage as the screen is being conveyed in the well, and ensures that each segment is appropriately positioned in contact with the inner tubular member and the adjacent segment, so that each segment is supported by the inner tubular member and no fluid leakage is permitted between adjacent segments, when the screen is expanded downhole. The inner tubular member has a large number of longitudinally extending slots formed therethrough, with the slots being circumferentially and longitudinally distributed on the tubular member. When the inner tubular member is expanded, each of the slots expands laterally, thereby becoming somewhat diamond-shaped.
Unfortunately, there are several problems associated with these types of expandable well screens. For example, manufacture is quite difficult due to the requirement of attaching individual screen segments to the inner tubular member in a circumferentially overlapping manner, and the requirement of positioning the segments within the outer shroud. Construction of the outer shroud is critical, since the shroud must be expandable yet sufficiently strong to maintain each screen segment in contact with an adjacent segment when the screen is expanded. If the screen segments are not in contact with each other, fluid may flow into the screen between the segments. Additionally, the inner tubular member configuration makes it difficult to connect the screen to other tubular members, such as blank sections of tubing, other screens, etc.
From the foregoing, it can be seen that it would be quite desirable to provide an improved expandable well screen. It is accordingly an object of the present invention to provide advancements in the technology of expandable well screens.
SUMMARY OF THE INVENTION
In carrying out the principles of the present invention, in accordance with an embodiment thereof, an expandable well screen is provided in which a filter element thereof is circumferentially pleated. The filter element may circumscribe an inner perforated base pipe. Associated methods are also provided.
In one aspect of the present invention, a disclosed well screen includes a filter element which is constructed in a radially compressed pleated configuration. The filter element may be made of a woven metal material. Subsequent radial expansion of the filter element “unpleats” the material, so that the filter element takes on a more circular cross-section.
In another aspect of the present invention, the filter element is constructed in multiple layers. An inner layer has openings therethrough of a size which excludes larger particles from passing through the openings, thus filtering fluid flowing through the openings. An outer layer has openings therethrough which are larger than the openings through the inner layer. The outer layer may be utilized to protect the inner layer against damage.
In still another aspect of the present invention, the well screen may be utilized in a method of servicing a subterranean well. In the method, the well is gravel packed with the screen in its radially compressed configuration. After gravel has been deposited in an annulus about the screen, the screen is radially enlarged, thereby displacing the gravel in the annulus.
In yet another aspect of the present invention, the well screen may be utilized in another method of servicing a subterranean well. In this method, perforations formed outwardly from the wellbore are pre-packed, that is, sand flow inhibiting particulate matter is deposited in the perforations. The screen is then radially enlarged opposite the perforations. In this manner, the screen retains the particulate matter in the perforations.
These and other features, advantages, benefits and objects of the present invention will become apparent to one of ordinary skill in the art upon careful consideration of the detailed description of representative embodiments of the invention hereinbelow and the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevational view of a well screen embodying principles of the present invention;
FIG. 2 is a cross-sectional view through the well screen, taken along line 2 — 2 of FIG. 1;
FIG. 3 is an enlarged view of a filter element of the well screen;
FIG. 4 is a schematicized view of a first method of servicing a subterranean well, the method embodying principles of the present invention;
FIG. 5 is a schematicized view of a second method of servicing a subterranean well, the method embodying principles of the present invention; and
FIG. 6 is an enlarged view of a portion of the well of FIG. 5 .
DETAILED DESCRIPTION
Representatively illustrated in FIG. 1 is a well screen 10 which embodies principles of the present invention. In the following description of the screen 10 and other apparatus and methods described herein, directional terms, such as “above”, “below”, “upper”, “lower”, etc., are used for convenience in referring to the accompanying drawings. Additionally, it is to be understood that the various embodiments of the present invention described herein may be utilized in various orientations, such as inclined, inverted, horizontal, vertical, etc., without departing from the principles of the present invention.
The screen 10 includes a filter element 12 , which is shown in FIG. 1 in its radially compressed pleated configuration. The filter element 12 is generally tubular and is circumferentially pleated, that is, it is folded multiple times circumferentially about its longitudinal axis. In this manner, the filter element 12 circumference as shown in FIG. 1 is substantially smaller than its circumference when it is in an “unpleated” or radially enlarged configuration. As used herein, the term “pleat” is used to include any manner of circumferentially shortening a circumferentially continuous element, and the term “unpleat” is used to include any manner of circumferentially lengthening a previously pleated element.
Referring additionally now to FIG. 2, the screen 10 is shown from a cross-sectional view thereof. In this view, it may be more clearly seen how the filter element 12 is folded so that it is alternately creased and thereby circumferentially shortened. In this view it may also be seen that the filter element 12 radially outwardly overlies an inner generally tubular perforated base pipe 14 . The base pipe 14 is optional, since the filter element 12 could be readily utilized in a well without the base pipe. However, use of the base pipe 14 is desirable when its structural rigidity is dictated by well conditions, or when it would be otherwise beneficial to provide additional outward support for the filter element 12 .
The base pipe 14 is preferably made of metal and is radially expandable from its configuration shown in FIGS. 1 & 2. Such radial expansion may be accomplished by utilizing any of those conventional methods well known to those skilled in the art. Additional methods are described in the application entitled WELLBORE CASING referred to above. For example, a device commonly known as a “pig” may be forcefully drawn or pushed through the base pipe 14 in order to radially outwardly extend the base pipe's wall.
Note that opposite ends 16 of the base pipe 14 are generally tubular and circumferentially continuous. In this manner, each of the ends 16 may be provided with threads and/or seals, etc. for convenient interconnection of the screen 10 in a tubular string. Specialized expandable end connections are not necessary. Thus, if it is desired to connect the screen 10 to another screen or to a blank (unperforated) tubular section, each end 16 may be connected directly thereto.
The filter element 12 is preferably made of a woven metal material. This material is well adapted for use in a filter element which is folded and unfolded, or otherwise pleated and unpleated, in use. The metal material may also be sintered. However, it is to be clearly understood that other materials, other types of materials, and additional materials may be utilized in construction of the filter element 12 without departing from the principles of the present invention.
Referring additionally to FIG. 3, an enlarged cross-sectional detail of the filter element 12 is representatively illustrated. In FIG. 3 it may be clearly seen that the filter element 12 is made up of multiple layers 18 , 20 , 22 , 24 of woven material. Fluid (indicated by arrows 26 ) flows inwardly through the layers 18 , 20 , 22 , 24 in the direction shown in FIG. 3 when the screen 10 is utilized in production of fluid from a well. Of course, if the screen 10 is utilized in injection of fluid into a well, the indicated direction of flow of the fluid 26 is reversed.
It will be readily appreciated upon a careful examination of FIG. 3 that layer 22 has openings 28 in its weave that are smaller than those of the other layers 18 , 20 , 24 . Thus, the layer 22 will exclude any particles larger than the openings 28 from the fluid 26 passing inwardly therethrough. The layers 18 , 20 inwardly disposed relative to the layer 22 are not necessary, but may be utilized as backup filtering layers in case the layer 22 were to become damaged (e.g., eroded), and may be utilized to provide structural support in the filter element 12 .
In one unique feature of the filter element 12 , the layer 24 outwardly the inner layer 22 and has openings 30 in its weave which are larger than the openings 28 through the inner layer 22 . Thus, the outer layer 24 will allow particles to pass therethrough which will not be permitted to pass through the inner layer 22 . However, one of the principle benefits achieved by use of the outer layer 24 is that the inner layer 22 is protected against abrasion, impact, etc. by the outer layer 24 during conveyance, positioning and deployment of the screen 10 in a well.
Referring additionally now to FIG. 4, a method 40 of servicing a subterranean well embodying principles of the present invention is representatively and schematically illustrated. In the method 40 , the screen 10 is utilized in a gravel packing operation in which gravel 42 is deposited in an annulus 44 formed between the screen and a wellbore 46 of the well. Methods of depositing the gravel 42 in the annulus 44 about the screen 10 are well known to those skilled in the art and will not be further described herein. However, it is to be clearly understood that a method of servicing a well embodying principles of the present invention may be performed using a variety of techniques for depositing the gravel 42 in the annulus 44 and using a variety of types of gravel (whether naturally occurring or artificially produced).
As shown in FIG. 4, the screen 10 is interconnected between a plug or sump packer 48 and a packer 50 . The construction of the screen 10 , particularly the configuration of the base pipe 14 as described above, convenient interconnection of the screen. In actual practice, one or more other tubular members may be interconnected between the screen 10 and each of the plug 48 and the packer 50 .
Perforations 52 extend outwardly through casing 54 and cement 56 lining the wellbore 46 . The screen 10 is positioned in the wellbore 46 opposite the perforations 52 . It is not necessary, however, for the screen 10 to be positioned opposite the perforations 52 , nor is it necessary for the perforations to exist at all, in keeping with the principles of the present invention, since the method 40 could alternatively be performed in an open hole section of the well.
When the gravel 42 has been deposited in the annulus 44 about the screen 10 , the screen is radially expanded from its initial radially reduced configuration to its radially enlarged configuration. Such radial expansion of the screen 10 redistributes the gravel 42 in the annulus 44 , for example, causing the gravel to displace upwardly about the screen in the annulus, eliminating voids in the gravel, etc. Additionally, radial expansion of the screen 10 may displace a portion of the gravel 42 into the perforations 52 . Note that it is not necessary for the filter element 12 of the screen 10 to be completely unpleated in the method 40 .
Referring additionally now to FIG. 5, another method 60 of servicing a subterranean well embodying principles of the present invention is representatively and schematically illustrated. Elements shown in FIG. 5 which are similar to those previously described are indicated in FIG. 5 using the same reference numbers. The screen 10 is depicted interconnected between the plug 48 and the packer 50 in the wellbore 46 , but other positionings and interconnections of the screen may be utilized without departing from the principles of the present invention.
In the method 60 , sand flow inhibiting particulate matter 62 , such as gravel, is deposited in the perforations 52 . This operation of depositing the particulate matter 62 in the perforations 52 is commonly referred to as “prepacking” and is well known to those skilled in the art. Therefore, it will not be further described herein. However, it is to be clearly understood that any technique of depositing the particulate matter 62 in the perforations 52 may be utilized without departing from the principles of the present invention.
After the particulate matter 62 has been deposited in the perforations 52 , the screen 10 is radially expanded from its initial radially reduced configuration to its radially enlarged configuration as described above. In one unique feature of the method 60 , the filter element 12 contacts the inner side surface of the casing 54 adjacent the perforations 52 when the screen 10 is radially expanded.
Referring additionally now to FIG. 6, an enlarged cross-sectional view representatively illustrating the interface between the screen 10 and one of the perforations 52 is shown. In this view it may be clearly seen that the filter element 12 of the screen 10 is in contact with the casing 54 surrounding the illustrated perforation 52 . In this manner, the screen 10 in its radially expanded configuration retains the particulate matter 62 within the perforation 52 .
It will be readily appreciated by one skilled in the art that the method 60 eliminates the need for depositing gravel 42 (see FIG. 4) in the annulus 44 about the screen 10 for retaining the particulate matter 62 in the perforations 52 , since the screen itself retains the particulate matter in the perforations. Note that it is not necessary for the filter element 12 of the screen 10 to be completely unpleated in the method 60 .
Of course, many modifications, additions, deletions and other changes to the embodiments described above will be apparent to a person of ordinary skill in the art upon consideration of the above descriptions, and these changes are contemplated by the principles of the present invention. Accordingly, the foregoing detailed description is to be clearly understood as being given by way of illustration and example only, the spirit and scope of the present invention being limited solely by the appended claims. | An improved expandable well screen and associated methods of servicing a subterranean well provide enhanced functionality, while increasing the convenience of manufacture and deployment of the screen, and reducing the screen's cost. In one described embodiment of the invention, an expandable well screen includes a pleated woven metal filter element disposed overlying a perforated base pipe. When the screen is appropriately positioned within a well, an expanding tool is utilized to radially enlarge the base pipe and filter element. | 4 |
This application claims benefits of Provisional application 60/051,075, filed Jun. 27, 1997.
BACKGROUND OF INVENTION
1. Field of the Invention
In general, the present invention relates to a flat field optical scanning system that can produce scan lines at high speeds, high resolution, and large formats. More particularly, the present invention relates to a flat bed optical scanning system with a polygon scanner having a fluid film bearing that accomplishes correction of repeatable and non-repeatable cross scan and in-scan errors such that the associated errors are reduced to negligible levels as the scanned energy of the laser beam is directed to its intended surface.
2. Description of the Prior Art
In a scanning system, the light source is typically a continuous wave gas laser or a laser diode. The laser beam produced by one of these devices is typically first collected by lenses that condition the beam to be either collimated or focused, is then deflected by the scan optic and then focused onto an imaging surface. Conditioning optics may also be part of the scan optic, or placed between the scan optic to influence focusing of the beam, or passive correction of scan curvature, or bearing cross-scan wobble correction using anamorphic optical elements.
Notwithstanding all of the above alternatives, the deflected light beams are scanned into a line that, when combined with a separate linear transport mechanism operating in a direction orthogonal to the scan line, produces a two-dimensional image made up of a series of small dots or pixels. Discrete picture elements (pixels or dots) are created by modulating the laser light source. A laser diode may be modulated directly by varying the applied power. A continuous wave gas laser may be modulated by use of outside means such as an acousto-optic modulator. The imaging surface itself may be either flat or curved, depending upon the optical design configuration and application of the particular scanning device. In a typical cylindrical imaging application, for example, a flexible photo-sensitive material is first loaded onto the inside or outside of the cylindrical surface matched in radius to the curvature of the scanned energy. The optical scanning device is then precisely moved along precision made rails at a constant speed along the center axis of the drum. The photo-sensitive material that is guided or attached to the cylindrical surface is scanned (or exposed) by the light beams reflected by the rotating scan optic of the optical scanning device.
Cylindrical imaging systems are inherently simple since the curvature produced by the operation of the scanner is corrected by the curvature of the cylindrical locating surface. In addition, the duty cycle or scan efficiency can approach 100% if the fall 360 degrees of the cylindrical surface is utilized. Cylindrical imaging systems do, however, have very significant limitations. The surface to be scanned (or exposed to the light) must be flexible and the length of the surface is limited by the length of the drum. While it may be possible to make the cylindrical surface very large in radius and very long, as a practical matter, cost and accuracy factors become increasingly prohibitive if the radius and length of the cylindrical surface exceed 18" and 48", respectively. Generally, in order to take advantage of the inherent simplicity of the cylindrical imaging configuration, only one scan line can be produced per revolution of the scanner. Thus the scanner must rotate at a high rate of speed to achieve a high scan rate. At high rates of speed, problems with noise, windage and deflection of the optical surface are increasingly problematic.
The rotatable scan optic in the cylindrical imaging context typically consists of a single mirror, an assembly of more than one mirror, or a glass prism with one or two reflective surfaces. Generally one scan line per revolution of the scanner is produced, although Kramer, U.S. Pat. No. 4,786,126, teaches a design whereby two scan lines per revolution may be produced. The rotatable scan optic may be mounted on a spindle supported by ball bearings or by a fluid film bearing. A fluid film bearing utilizes a gas or oil to separate and lubricate sliding surfaces and may be externally pressurized or generate its own internal pressure, referred to as self-acting. Fluid film bearings are superior to ball bearings in terms of rotational accuracy, repeatability, and high rotational speeds.
The ideal cylindrical scanning system will be capable of a very high rate of scan, high resolution, and high scan efficiency while maintaining these qualities for large sizes of reproductive media. For example, see U.S. Pat. No. 5,610,751, to Sweeney et al., that teaches a self-acting gas bearing enclosed in a spherical windowed housing used to establish an accurate, high speed, low noise, lubrication-free, contamination protected, long living, scan motor and optical assembly. Self-acting gas bearings are preferred for high performance cylindrical imaging applications where exceptional accuracy, high rotational speeds, and low velocity jitter are required. Since cylindrical imaging systems utilize, as a general rule, one scan line per revolution, the accuracy and repeatability in the registration of adjacent scan lines is solely dependent on the accuracy and repeatability of the bearing and the motor velocity control system. The use of a gas film bearing provides an accurate platform that has become the predominant technology for cylindrical imaging systems.
To summarize, cylindrical imaging systems are inherently simple, but lack the general utility of flat field systems, since they must reconcile large cylindrical surfaces and flexible reproductive materials. As demonstrated above, it is also increasingly problematic to design and operate a single scan line per revolution scanner as the scan rate is increased, aperture size and resolution is increased, and imaging format size is increased.
In a typical flat field imaging application, a photo-sensitive material, for example, is moved at constant speed by a capstan roller or other linear conveyor means, fed from continuous rolls or precut cassettes of stacked material to present the material to a stationary optical system for scanning. Alternatively, stationary photo-sensitive material may be imaged by translating the optical system. Flat field systems have superior general utility over cylindrical imaging systems because the surface that is to be imaged onto or inspected is not required to be finite in length, need not be flexible and may thus be fed continuously at great speed. Imaging of stiff metal plate materials and inspection of electronic components require the use of flat field scanning systems.
The scan optic in the flat field imaging context typically consists of a resonating or rotating single facet mirror, or an assembly of two or more mirrors, or a glass prism consisting of one or two reflecting surfaces. It is also common to have a rotating polygon or hologon having multiple reflective or refractive facets symmetric to a central rotating axis.
Flat field systems require the use of additional conditioning optics to flatten the curvature produced by the rotation of the scanner as the beams are swept into an arc. This correction is commonly known as f-theta correction. F-theta curvature error can otherwise be corrected by imaging onto a cylindrical surface having a matched radius of curvature as discussed previously. F-theta curvature may also be corrected by refractive (lenses) or reflective (mirrors) means. F-theta conditioning optics for large format, high resolution applications, typically cannot perform adequately for angles of scan much greater than 22.5 degrees of scanner rotation (45 degrees of optical scan angle) out of a total of 360 degrees. This results in an effective scan efficiency of approximately 12% for a flat field, rotating, single facet scan optic that can produce only one scan line per revolution compared to up to 100% scan efficiency that can be achieved with the cylindrical approach. Alternatively, the duty cycle of a single facet resonant scanner is improved to 30-35% at the expense of large variations in scan velocity which must be corrected for in modulation of the laser beam. This loss of scan efficiency is a significant disadvantage since the rate at which the laser must be modulated and the instantaneous power of the laser must both be increased significantly compared to the cylindrical imaging case for a given rate of scan due to the dramatic reduction of scan efficiency. If a multi-facet device is used, such as a polygon or hologon, each facet can service the 22.5 degree acceptance angle of the f-theta optics thus the scan efficiency for a polygon or hologon scanner for flat field systems can be as high as 50-80% if 8-12 facets are used. However, the use of multiple scan surfaces on the scan optic to multiply the effective scan rate, as is the case for both the polygon or hologon scanners, produces undesirable side effects unique to these types of scanners. The use of a multi-faceted holographic rotating scanner has unique advantages with respect to cross-scan error and scan efficiency compared to a rotating polygon scanner. Its principal disadvantage is the requirement for a laser having refined wavelength stability. Such a device also cannot be used for alternative wavelengths without change of design and is completely unsuitable for simultaneous multiple color scanning.
Multi-facet scanners in general, and polygon scanning systems in particular, have inherent limitations in that corrections must be made for relative errors in the facets of the polygon that deflect laser energy to create a scanned line. As the object of scan is moved away from the scanner, as is the case for large imaging formats, and as the resolution is increased, very small errors in the facets of the polygon in relation to its rotating axis and variation in the rotating velocity can produce noticeable errors. These errors are commonly known as cross-scan and in-scan related errors.
It is known to use anamorphic correcting optics that can correct for cross-scan errors. These optics become increasingly difficult and expensive to design and manufacture as the size of the imaging format increases. Typically, the anamorphic cross-scan correction approach is cost and performance limited for scan widths greater than 14" and resolution greater than 2,000 dots per inch. Though it is known to use anamorphic correction with flat field system widths of as large as 26", the cost for such a system is prohibitive. An additional disadvantage of the anamorphic approach is that the use of multiple wavelengths of light, especially at the same time, is restricted.
A well known alternative to the anamorphic approach is the use of an active cross-scan correction approach that simplifies the optical design significantly by eliminating the need for anamorphic correction elements that would be very large and very expensive for large format operations and that restricts the goal for having a system that is polychromatic. Besides the cross-scan error, the in-scan error component is also of equal importance for both cylindrical and flat field imaging. For a rotating optic producing a single scan line per revolution, in-scan errors are solely attributable to the accuracy and repeatability of the rotating velocity. To a significant extent, the accuracy need not be as good as the repeatability. For imaging systems, small variations in velocity that repeat at the same place from one scan line to the next do not produce an error that is noticeable to the human eye. Multiple facet scanners such as the rotating polygon require more refined accuracy of velocity control as well as repeatability since each facet represents a fraction of the total rotation and the period of each fraction must be nearly identical. Otherwise in-scan related errors become readily visible.
In the use of a polygon scanner, whether passive or active means are used to correct for cross-scan error, the rotatable scan optic is commonly mounted on a shaft supported by a bearing assembly normally including radial and thrust support components. Fluid film bearings are used in scanners of all types where exceptional accuracy, high rotational speeds, and low velocity jitter are required.
It is essential to the present discussion, in view of the lack of common terminology within the optical scanning and precision instrument industry in general, to distinguish between non-repeating and repeating sources of error. Non-repeating or random errors are difficult to isolate and correct. Sources of non-repeating errors in the context of optical scanning devices are often caused by aerodynamic or windage effects on the rotating optic or errors in the bearing supporting the scan optic that defines the axis of rotation of the scanner.
Repeating errors recur in the form of periodic and predictable patterns and can generally be measured, and in many cases compensated for, using feedback error correction.
Within the flat field applications, it is well known that the rotating polygon scan optic has greater potential for speed and efficiency compared to the use of the resonating scanner or single facet rotary scanner. The polygon scan optic is superior because for each rotation thereof, a polygon scan optic having "n" number of facets produces "n" number of scan lines, whereas for the single facet rotary scan optic or resonating scanner, for each revolution of the scan optic, one scan line is produced. Thus, to obtain a high resolution image on a given imaging surface in as short amount of time as possible, it is desirable to maximize the scan rate of the scan optic. In addition to the rotating polygon scanner operating at a greater scan rate, it can use a larger aperture, and the reflecting surfaces of the polygon scan optic are less susceptible to distortion from centrifugal body forces by comparison to single facet, rotating or resonant scanners.
However, this potential of the polygon scan optic cannot be realized unless scanning errors unique to the polygon scanning device can be reconciled in the design of the overall scanning system. In this regard, it is important to note the image producing quality and productivity of a polygon optical scanning device depends largely on its precision and on the scan rate and scan efficiency of the device's polygon scan optic, respectively. Precision is necessary to achieve higher resolutions, and a higher scan rate and efficiency are necessary to generate the high resolution images faster.
One significant scanning error common to polygon scanning devices is "cross-scan" error. Cross-scan error specifically refers to errors in the placement of scan lines in a direction perpendicular to the lines being scanned. The polygon cross-scan error phenomena is the result of one or more of three separate sources of error. The first source of error is the accuracy of the rotating axis of the motor-driven bearing assembly on which the polygon is mounted or integral to. This type of error is generally non-repeating in nature. The second source of error is the parallelism of the true rotating axis of the spindle and the virtual axis of the polygon. This type of error is generally repeating in nature. The virtual axis is defined as that axis best fitted to the relative angles of each of the polygon facets. The third source of error is the relative angle errors of each facet to the defined best-fit virtual axis. This error is also repeating in nature. All of these errors sum together resulting in composite cross-scan error.
Because of the above noted superior advantages of flat field scanning compared to cylindrical scanning, it has been the subject of many efforts in the prior art to develop polygon scan optic systems with various error correction schemes. For example, U.S. Pat. No. 5,365,364, to Taylor, discloses and teaches the design of an all reflective flat field imaging system with multiple facets, having high scan efficiency, suited for use at numerous operating wavelengths of light enabled by the all reflective design. The Taylor device is taught as being aerodynamically smooth to reduce bearing perturbation due to windage and, accordingly, it has a potential for improved scan rate enabled by improved scan efficiency.
U.S. Pat. No. 5,281,812, to Lee et al., discloses and teaches a flat field imaging system with an f-theta lens that utilizes a closed loop control system to correct for the repeating and non-repeating cross-scan errors of a polygon scanner in real time by implementation of a novel piezoelectric driven mirror. Lee et al. teach the limitation of single faceted scanners in the flat field context, the problems with acousto-optic modulators to influence cross-scan correction, and the cost and implementation limitations of the use of anamorphic cross-scan correction optics. Lee et al. also teach the fundamental limitations of the natural frequency of the spring-mass system embodied in the implementation of a mirror driven at high frequency by piezoelectric actuators.
U.S. Pat. No. 5,247,174, to Berman, discloses and teaches a flat field imaging system having an f-theta lens that utilizes a closed loop control system to correct for the repeating and non-repeating cross-scan errors of the polygon scanner in real time by attaching the end of a fiber optic coupled to a gas laser onto a piezoelectric actuator and correcting the errors of the polygon scanner by moving the laser beam source.
U.S. Pat. No. 4,441,126, to Greenig et al., discloses and teaches a beam deflection system having an acousto-optic modulator connected to a lens located between the laser and the polygon scan optic. The Greenig et al. reference discloses a sensor and bridge circuit to sense the position of the beam scan and error value for each facet of the scan optic. The values are averaged and a correcting signal and voltage adjustment are supplied to adjust the balance of the bridge to drive the average value toward a reference value.
U.S. Pat. No. 4,054,360, to Oosaka et al., discloses and teaches an improved method and apparatus for removing scanning error associated with the lack of perfect parallelism in a rotating polyhedral mirror. Oosaka et al. teach the use of an incident beam directed along a vertically independent optical patch and brought back into incidence on the same mirror deflection point to eliminate the error in parallelism without interfering with the horizontal scanning of the reflected beam.
The examples of prior art mentioned above focus on reduction of scanning errors in polygon scanning systems by utilizing active and passive means to reduce the repeating errors, but fail to disclose, teach or suggest the use of a fluid film bearing for rotating the polygon scan optic to reduce the non-repeating errors. The accuracy of these systems are limited by the accuracy of the bearing system which typically induces significant non-repeating errors. Alternatively, if a fluid film bearing, or more specifically, a self-acting gas bearing is utilized to reduce non-repeating errors in conjunction with active or passive means to correct for repeating errors, then a significant reduction of composite errors is realized and system accuracy improved.
Moreover, the inherent accuracy and repeatability afforded by a fluid film bearing also enables the use of an open loop control system for active correction of repeatable scanning errors. Open loop correction techniques are not practical for polygon scanning applications unless the non-repeating component of the system errors is reduced to negligible levels.
Active and passive error correction techniques are well known in the art. Active cross-scan correction implies that the errors are continuously tracked or mapped in the operation of the system and some sort of mechanism within the design continuously implements an equal and opposite error to that of the composite error of the rotating polygon sub-system. Prior art techniques include the use of an acousto-optic modulator in the path between the laser source and the rotating polygon. The acousto-optic modulator can be used to re-direct the beam at precisely the opposite angle that each polygon facet requires to achieve negligible cross-scan error. An alternative approach that has been used is to tilt a mirror in the system by use of a device such as a piezoelectric actuator or voice coil type of actuator. Piezoelectric actuators, voice coil actuators, and many other types of actuators of similar vein are broadly classified as electro-mechanical actuators.
A second undesirable source of error in optical scanning systems results from "in-scan" error. In-scan error specifically refers to errors in the placement of scan lines in a direction parallel to the lines themselves. In-scan error can also cause cross-scan errors since velocity variations of the polygon scan optic result in placement errors on the scanned media. Like cross-scan error, in-scan error is also the result of several components both repeatable and non-repeatable. The first source of in-scan error is related to the accuracy of the rotating axis of the bearing. If the rotating axis of the bearing is not perfectly aligned with the rotating axis of the polygon scan optic, there will be some repeatable error. The second error is the relative height of each of the polygon facets to the axis of rotation of the bearing. If the bearing has a nearly perfect axis of rotation, as is the case for a fluid film bearing, facet height errors are isolated to the manufacture of the polygon and its registration to the bearing axis. Facet height errors result in length variations from one scanned line to the next. The error pattern is repeatable with each fall rotation of the polygon. Facet height errors can be reduced to negligible levels by controlled manufacturing processes applied to the manufacture of the polygon. This error may also be corrected by inducing small variations in the rotating velocity of the scanner.
The third error affecting in-scan error relates to the accuracy of the speed control feedback control system that governs the rotational velocity of the polygon. The in-scan error problem for the polygon scanning system is most significant for high resolution, flat field imaging systems. This is because the distance from the polygon to the reproductive media tends to be large and incremental velocity errors less than 1/1,000,000 of a revolution of the scanner can produce noticeable in-scan related artifacts. Single facet scanning systems can tolerate much greater velocity variation so long as the velocity profile repeats from one revolution of the scanner to the next. As an example, typical single facet, air bearing, rotary scanners have incremental velocity errors on the order of 5-10 parts per million/revolution (PPM/rev) but repeat at any point of interest in the scan to a precision of less than 1.0 PPM/rev. Since the polygon scanner generates a multiplicity of scan lines per revolution, incremental velocity variation cannot be tolerated.
It is important to distinguish between "short-term" and "long-term" errors. Short-term errors are defined herein as errors that appear within fractions of a revolution up to several thousand revolutions of the rotating scanner. Long-term errors are defined as errors that occur over more than several thousand revolutions of the rotating scanner, or otherwise defined over a significant period of time or number of scan lines. Short-term and long-term errors can both be repeating and non-repeating in form. Very small short-term errors are known to produce imaging anomalies such as "banding". In general, larger errors spread over longer periods of time can be tolerated. Actual tolerances depend on many factors unique to a particular imaging application including error spacial frequency, image contrast, and overall image distortion.
In summation, the prior art has yet to disclose or teach singularly, or in any combination, and there continues to be a significant need for, a large format, flat field, high resolution, high speed optical scanning system, at a cost that makes such a device practical and usable in a significant number of applications. More particularly, the prior art is lacking and there remains a need for a flat field scanning system that utilizes a polygon scanner with a fluid film bearing to reduce non-repeating scanning errors, and has an open loop control system for active correction of repeatable scanning errors, and is capable of producing large formats at high resolution and high scan rates.
SUMMARY OF THE INVENTION
The objective of the disclosed invention is to present a flat field imaging approach that can match the resolution of current cylindrical imaging systems, match the format sizes of such systems, surpass the scan rate possible with such systems, while realizing the superior utility of a flat field system over the cylindrical imaging approach. The present invention resides in a flat field optical polygon scanning device specifically developed for large format, high scan rate, high resolution, monochromatic and polychromatic flat field scanning for imaging and inspection purposes.
In particular, the present invention relates to a polychromatic polygon scanning system having a rotating polygon scan optic, a fluid film bearing rotatably supporting the rotating polygon scan optic, and scan error correction. More specifically, the fluid film bearing is a self-acting gas bearing having exceptionally low non-repeating error. The scanner of the present invention further includes a chamber fitted with a window, for reducing non-repeatable errors induced by windage from the rotating polygon scan optic, a phase lock loop control system premised on the use of the fluid film bearing with low velocity jitter, a reflective multi-spectral f-theta correction scheme, a solid-state laser light source, and a cross-scan correction mechanism to displace position of the laser diode to influence the angle of the laser beam as it addresses each facet of the polygon. The cross-scan correction mechanism has a high natural frequency and very small inertia so that the device can be operated at exceptionally high speeds to actively correct for the repeating cross-scan errors identified in the scanning system under consideration.
The present invention also relates to a method for identifying and correcting the repeatable errors in a polygon scanning system having a fluid film bearing for the rotating polygon scan optic.
The disclosed invention results from the systematic reduction of sources of non-repeating, short-term error. Once the sources of short-term, non-repeating error are minimized, short-term repeating errors can be measured, isolated and reduced by several methods. The short-term repeating errors are separated into "cross-scan" and "in-scan" components.
By use of a fluid film bearing in general and a self-acting gas bearing in particular, aerodynamic streamling of the polygon scan optic, and a windowed enclosure surrounding the rotating polygon scan optic to minimize windage induced errors, the non-repeating component of the cross-scan error can be virtually eliminated leaving only the repeatable component. The repeatable component can then be measured, isolated and reduced by active correction using a cross-scan correction mechanism and an open loop control system.
In the context of the use of polygon scanners for generating scan lines onto reproductive media, repeatable and non-repeatable cross-scan errors manifest reduction in the image resolution that is directly proportional to the magnitude of the composite error. If the accuracy of the bearing is the least significant error, as is the case for a fluid film bearing, and air turbulence effects are minimized, a repeatable cross-scan error pattern known as "banding" will be produced. Since the banding phenomena is highly undesirable, and since it is highly repeatable with every period of rotation of the scanner, the present invention measures and corrects cross-scan errors to eliminate banding.
To successfully implement an active cross-scan correction system for polygon scanners using electro-mechanical motive devices such as piezoelectric or voice coil actuators, or electro-optical devices that influence apparent movement of the laser source, the present invention uses a self-acting gas bearing to ensure rotational axis repeatability and minimize non-repeating errors.
As with the cross-scan error component, the non-repeating error component of the in-scan error is made negligible by using a polygon scanner having a fluid film bearing in general and a self-acting gas bearing in particular, aerodynamic streamlining of the polygon scan optic, and a windowed enclosure surrounding the rotating polygon scan optic to minimize windage induced errors. In addition, an optical encoder is provided on the rotating shaft of the self-acting gas bearing to generate a highly repeatable shaft rotation reference. The low friction, high precision of the self-acting gas bearing, combined with the repeatable optical encoder, provides the unique capability of outstanding velocity control in the polygon scanner of the present invention.
Like with the cross-scan error component, the essential issue for correcting the in-scan error is that the non-repeatable component of the in-scan error is virtually eliminated leaving only the repeatable component, which can be measured, isolated and reduced by active correction, in this case, using the outstanding velocity control of the polygon scanner.
The most basic approach to reconciling in-scan errors is the design and manufacture of the bearing, polygon scan optic and velocity control system to such a degree that residual in-scan errors will have negligible effects on images created. The present invention makes it possible to uncouple the performance of the polygon imaging subsystem from the electronics control system for modulating the laser subsystem. This approach makes possible the design and production of the polygon imaging subsystem as a stand-alone product capable of interfacing with a wide variety of application platforms. Thus, the rotational velocity of the polygon scanner is controlled to sufficient precision to eliminate in-scan related artifacts or the need to actively synchronize the modulation of the laser with rotation of the scanner.
The fluid film bearing, or more particularly a self-acting gas bearing, for the polygon scanning subsystem, the use of the active cross-scan correction technique to correct for repeating relative tilt errors in the polygon facet, and the use of a feedback control system premised on the repeatable encoder enabled by the use of the fluid film bearing offers great freedom to the design of the post scan conditioning optics. In effect, the design of the post scan conditioning optics are designed as if a perfect rotating polygon were in use. As previously discussed, for the context of flat field imaging, f-theta corrective optics are used to flatten the curvature of the reflected scanned imaging field. The present invention allows the use of reflective f-theta optics to provide a design that results in a nearly universal flat field line imager that can be uncoupled from the laser modulation and can be operated over a broad range of laser wavelengths without chromatic dispersion. Besides more universal use for a broad range of single wavelength applications, the disclosed system is well suited for full color simultaneous imaging. The disclosed invention also readily accommodates the use of refractive f-theta optics as well.
Piezoelectric actuators and other beam deflection technologies such as those based on the electro-optic principle are available at reasonable cost to influence correction of polygon cross-scan errors. The essential feature of the disclosed invention is to reduce the non-repeating errors to such a degree that the repeating residual error may be accurately measured and then corrected.
The electronics of the present invention for correcting the cross-scan and in-scan errors are relatively simple, readily available and, therefore, relatively low in cost. The present invention also uses a rotational velocity control subsystem that is relatively low cost and is particularly well suited for use with the self-acting gas bearing of the present invention combined with a relatively low cost optical encoder.
The disclosed invention is simple, is adaptable to large apertures, is well suited to imaging or inspection of flat widths greater than 14" and infinite in length, is capable of scan rates greater than 1,000 Hz, is capable of resolutions greater than 1,000 dpi, is uncoupled from the laser modulation to produce near identical scan lines from one facet to the next, and, because of its reflective design, is well-suited for color imaging. In view of the above, many objects and advantages are achieved by the present invention.
It is an object of the present invention to minimize the influences of non-repeating short-term errors by use of a fluid film bearing, more specifically, a self-acting gas bearing in combination with aerodynamic streamlining and the use of a windowed chamber to further minimize non-repeating perturbations due to windage.
It is a further object of the present invention to identify the residual repeating error and non-repeating error components of the polygon scan optic and minimize the non-repeating error to a negligible amount.
It is another object of the present invention to provide a polygon scanner having a means for correcting repeating residual error components of cross-scan and in-scan errors associated with the operation of the rotating polygon scanning system.
It is a further object of the present invention to provide a polygon scanner having a precise rotating axis which is controlled by an electronic control system to separately influence the repeating in-scan and cross-scan error components.
It is a further object of the present invention to provide a polygon scanner according to the present invention having the in-scan error minimized by the use of a velocity feedback control system that depends on the repeatability of an optical encoder operating on the rotating axis of the self-acting air bearing spindle.
It is another object of the present invention to provide a polygon scanner having a cross-scan error that is minimized by the high speed displacement of a diode laser by a piezoelectric actuator or tilt of a mirror to influence a virtual displacement of the diode laser, actuated by information from a repeatable error profile stored in memory, and the real or virtual displacement of the diode laser causes an angular shift of the beam that is equal and opposite to the error on each facet of the polygon scan optic. For use of a gas laser or in the use of simultaneous color imaging, the preferred embodiment will be a mirror tilted by the use of a piezoelectric actuator. For the use of a single wavelength application that uses a laser diode, the preferred embodiment is to mount the laser diode directly to the piezoelectric actuator. For the use of a gas laser or for the use of simultaneous introduction of multiple laser colors, the use of a piezoelectric tilted mirror is the preferred embodiment. An electro-optic device may also satisfy the conditions for any of the above laser implementation scenarios.
It is a further object of the present invention to provide a polygon scanning system having a cross-scan error profile that is continuously corrected by synchronizing the high speed displacement of a diode laser, by means of a piezoelectric actuator, in a direction opposite an amount equal to the repeatable error for a particular facet of the polygon scan optic.
It is further the object of the present invention to provide an optional self-calibration system that periodically senses small repeating errors caused by long-term drift, creates an electronic map of the repeating errors, electronically corrects for the repeating errors, provides the means to correct for long-term drift, and therefore periodically self-calibrates the factory measured polygon error profile. Because of the use of the self-acting gas bearing, the correction can be made solely by influencing the phase and amplitude of a sinusoidal component that is summed into the correction map established at the factory. Because of the exceptional short term repeatability of the self-acting gas bearing, sinusoidal phase and amplitude correction need not be introduced at a high update rate.
It is a further object of the present invention to provide a velocity control system that operates exclusive of the cross-scan correction system. As a direct consequence of the use of a gas bearing and other means to reduce non-repeating errors to a negligible level a repeatable composite error profile, as constructed by measurement of the period of each scan, may be recorded. An inverse error may then be summed into the phase-locked velocity control system to substantially correct the in-scan error.
It is yet another object of the present invention to provide a large format, high scan rate, high resolution, flat field imaging, polygon scanning system having reflective f-theta correction optics, that utilizes a polygon scan optic rotatably supported by a fluid film bearing and active correction.
It is a further object of the present invention to provide a rotating polygon scan optic having a self-acting gas bearing, a windowed enclosure surrounding the rotating polygon scan optic, and an active error correction system for realizing exceptionally high scan rates compared to resonant scanners and single facet scanners while also yielding a greater scan efficiency.
It is yet another object of the present invention to achieve the above mentioned objects in a device that can be manufactured at a relatively reasonable cost that was not previously possible.
It is yet another object of the present invention to provide a scanning system that is modular in design and interactions with a means for conveying the object to be scanned and computerized means to modulate the laser element itself such that the general utility of the subject invention is optimized as a stand-alone product to service many different customers in various industries.
These and other objects of the present invention will become apparent from the following detailed description of the preferred embodiment taken in conjunction with the attached drawings that are briefly described as follows.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective schematic view of a flat field open loop polygon scanning system of the first embodiment.
FIG. 2 is a perspective schematic view of a flat field polygon scanning system with optional self-calibration for correcting long-term drift.
FIG. 3 is a section view of a first embodiment of the flat field polygon scanning system;
FIG. 4 is a cross sectional view of an alternate embodiment of a stationary laser diode and an electro-optic device.
FIG. 5 is an optical schematic of a laser light service using a collimated stationary light source;
FIG. 6 is an optical schematic of a laser light source using a diverging stationary light source;
FIG. 7 is a graph illustrating the highly repeating nature of the periodic, in-scan error for eight revolutions of an eight facet polygon scan optic connected to a self-acting gas bearing according to the present invention;
FIG. 8 is a graph that illustrates the improvement achieved by accurately measuring the highly repeatable in-scan error profile and influencing appropriate correction;
FIG. 9 is a graph that illustrates the highly repeating nature of the cross-scan error for eight revolutions of the polygon scan optic as it is rotated on a self-acting air bearing according to the present invention;
FIG. 10 is a graph that illustrates the improvement achieved by accurately measuring the highly repeatable cross-scan error profile and influencing appropriate correction.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1 there is shown an open loop flat field polygon scanning system 10. The open loop flat field polygon scanning system includes a rotating polygon optic device 50 having a fluid film (self-acting gas) bearing 88. The scanning system 10 includes a line scan speed control 100, phase locked to the outputs of an optical encoder 51 attached to and precisely aligned to the spin axis of the polygon optic device 50 and generates an output controlling the rotational speed of an electric motor 52 and a multi-facet polygon mirror or scan optic 54. The polygon mirror 54 has a plurality of facets 56 arranged about its periphery. The polygon scanning system 10 also includes an open loop cross-scan error correction subsystem 200 responsive to scan position data output from sync logic circuitry 102 generates an output signal actuating a piezoelectric actuator 60.
A laser diode 62 attached to the piezoelectric actuator 60 generates a laser light beam 64 that is directed towards the rotating polygon scan optic 54 through a window 66. The laser diode 62 is translated by the piezoelectric actuator 60 to correct for repeatable angle errors in the polygon optic device 50. Laser conditioning optics 68 are disposed between the laser diode 62 and the rotating polygon scan optic 54. The laser light beam reflected from a facet 56 of the rotating multi-facet polygon scan optic 54 is directed to the media 70 to be scanned.
A linear transport mechanism 72 transports the media 70 in a direction indicated by arrow 74 normal to the scan direction of the laser light beam indicated by arrow 76. Refractive or reflective correcting optics 28 are disposed between the polygon scan optic 54 and the media 70 being scanned.
The line scan speed control 100 consists of sync logic circuitry 102 that receives an index signal (one per revolution) and count signal (increments/revolution) from the optical encoder 51 and generates a scan position signal. The scan position signal is used to synchronize the in-scan and the cross-scan error correction subsystem 200 with the rotational position of the rotating polygon scan optic 54. In this way the in-scan and cross-scan errors are mapped to the corresponding facet of the polygon scan optic 54. A second output of the sync logic circuitry 102 is received by a fixed pattern error EPROM 104 that stores the residual in-scan velocity error that is used as a correction factor to minimize the actual beam velocity errors at the image plane. The fixed pattern error EPROM stores information of the residual in-scan errors due to the encoder disk run-out and facet height variations of the multi-facet polygon scan optic.
A reference generator 106 provides the necessary frequency reference to a phase detector 110 by dividing down the output frequency of a quartz oscillator 108. Speed selection of the polygon scan optic 54 is performed by operator selection of a division factor needed to generate the appropriate reference frequency for each speed. The output of the reference generator 106 must be stable and virtually jitter free. The phase detector 110 receives the sync signal from the sync logic circuitry 102 and the count signal from the optical encoder 51 and outputs an analog error voltage that is summed with the output of the fixed pattern error EPROM 104 in a servo compensation circuit 112. A digital to analog (D/A) converter 116 converts the digital output of the fixed pattern error EPROM 104 to an analog signal prior to being summed with the output from the phase detector 110. The servo compensation circuit 112 provides the necessary gain needed to close the velocity phase loop and maintain system stability. A PID control loop is implemented at this point forming a type II control system that maintains a tight control over the rotational rate of the polygon scan optic 54. The motor speed is controlled by a Pulse Width Modulator (PWM) and commutation circuit 114 in response to the output from the servo compensation circuit 112. While a standard three phase brushless DC motor 52 is the preferred embodiment, and is represented in FIG. 1, any suitable motor type and electronic drive circuitry may be used, such as a hysteresis synchronous or permanent magnet brush type DC motor.
The cross-scan error correction subsystem 200 consists of a facet error EPROM 202 storing cross-scan error correction information for each facet 56. The facet error EPROM 202 is addressed by the scan position data received from the sync logic circuit 102 and outputs cross-scan error correction data The cross-scan error correction data is applied to the piezoelectric actuator 60 through a digital to analog (D/A) converter 204 and a high voltage amplifier 206. The piezoelectric actuator 60 converts the output of the high voltage amplifier 206 into a mechanical displacement, modulating the position of the laser diode 62 in a way so as to cancel the polygon angle errors.
Prior to use, the polygon scanning system 10 is calibrated to define the repeatable in-scan and cross-scan errors that are stored in the fixed pattern error EPROM 104 and the facet error EPROM 202, respectively. FIGS. 7-10 illustrate the means by which these errors may be measured and verified.
After calibration, the operation of the flat field polygon scanning system 10 is as follows:
The polygon optic device 50 is actuated and the multi-facet polygon scan optic 54 is rotated at the desired speed under the control of the line scan speed control 100. Each facet 56 of the polygon scan optic 54, one at a time, will reflect the light beam generated by the laser diode 62 to scan the media 70 on the linear transport mechanism 72 in a direction indicated by arrow 76 normal to the direction of motion of the media indicated by arrow 76. The correction for fixed pattern errors from the fixed pattern error EPROM 104 is addressed by the scan position data output from the sync logic circuitry 102 and is applied to the servo compensation circuit 112 to correct for in-scan fixed pattern errors. In a like manner, the facet error EPROM 202 is addressed by the scan position data output of the sync logic circuitry 102 and is applied to the piezoelectric actuator 60 to displace the laser diode 62 correcting for cross-scan errors in the scanning of the media.
Referring to FIG. 2 there is shown an optional self-calibration embodiment of the flat field scanning system. In this embodiment the polygon optic device 50, the piezoelectric actuator 60, the laser diode 62, laser conditioning optics 68, the refractive or reflective correcting optics 28, the media 70, the linear transport mechanism 72, and the line scan speed control 100, are the same as discussed relative to FIG. 1. The cross-scan error correction subsystem 300 differs from that shown in FIG. 1. In the self-calibrated embodiment, the linear transport mechanism 72 includes a cross-scan error detector 78 that provides periodic, long-term cross-scan error information to a cross-scan error processor 308 through an amplifier 310. The cross-scan error processor 308 also receives scan position data from the sync logic circuitry 102 and contains a correction algorithm necessary to implement a cross-scan correction update scheme. The outputs from the cross-scan error processor 308 drive a sine-error EPROM 312 that also receives scan position data from the sync logic circuitry 102. The sine-error EPROM 312 contains a sine function that is mapped over a 360 degree range. The phase and amplitude of the sine function is independently adjustable and is controlled by the scan error processor 308.
A facet error EPROM 302 and a digital-to-analog converter 304 are substantially the same as the facet error EPROM 202 and analog-to-digital converter 204 discussed relative to FIG. 1. The output of the sine-error EPROM 312 is converted to an analog signal by the digital-to-analog converter 314 and summed by a summing circuit 316 with the output of the digital-to-analog converter 304. The amplified signal is then applied to the piezoelectric actuator 60 through a high voltage amplifier 306. The amplitude of the output of the digital-to-analog converter 314 is controlled by the scan error processor 308.
Referring to FIG. 3 there is shown a first embodiment of of the flat field polygon scanning system 10. The scanning system consists of a housing 11 partially enclosing the laser conditioning optics 68, the polygon optic device 50 and the correction optics 28. The piezoelectric actuator 60 and the laser diode 62 are mounted in a laser support 12 attached at one end of the housing 11, and the polygon optic device 50 is mounted at the opposite end of the housing 11 within a separate chamber 14 to reduce the influence of windage. The laser conditioning optics 68 are attached to a support cylinder 16 extending from the laser support 12 into the housing 11. A f-theta correcting mirror 20 corrects for f-theta field curvature and directs the converging laser light to the designed flat field line image indicated at 76. Laser light is emitted by the laser diode 62 that then encounters the laser conditioning optics 68 that direct the laser light to the rotating polygon scan optic 54 through the window 66. The laser diode 62 is modulated by a separate electronic control system that is not part of the disclosed invention. The laser conditioning optics 68 expand, collimate, and focus the laser light for presentation to the facets of the rotating polygon scan optic 54. The axis of the rotating polygon scan optic 54 is tilted so that each facet of the polygon scan optic encounters the conditioned laser light beam and directs the light to a post-scan flat mirror 18 attached to the housing 11 where it is reflected to a f-theta correcting mirror 20 that serves to flatten the curvature of the laser beam as it expands to the desired scan line width at the media 70. The light reflected from the f-theta correcting mirror 20 is directed to a second flat mirror 22 mounted within the housing 11 from which it is reflected to the media through an aperture 24 provided in the housing 11. A dust cover 26 encloses the housing 11 and limits ingress of dust and other contaminants into the optical cavity.
Successive adjoining facets of the rotating polygon scan optic 54 similarly encountering the conditioned laser light emitted by the laser diode 62 will cause the light to be sequentially scanned across the media 70. Each facet will have repeatable errors relative to each other and the true rotational axis of the rotating polygon scan optic 54. The piezoelectric actuator 60 with the laser diode 62 attached will move the laser diode in a linear fashion such that the trajectory of the light emerging from the conditioning optics 68 are scanned parallel to each other.
The polygon optic device 50 has a support member 80 fixedly attached to the housing 11 within the separate chamber 14. The self-acting gas bearing 88 has a rotatable spindle 90 on which is attached the rotating polygon scan optic 54, the electric motor 52, and an optical encoder 51. The optical encoder has a high density count track and index track to provide precise information of the rotation rate of the spindle as well as its precise angular position. The count track and index track information provided by the encoder is highly repeatable since the encoder is mounted directly to the spindle 90 of the self-acting gas bearing 88. Repeatable errors in rotation rate and angular position resulting from errors in the encoder are corrected by the same means that other repeatable errors in the polygon scanning system are corrected.
FIG. 4 shows an alternate embodiment for displacing the light beam emitted by a source of laser light. In this arrangement the laser light source 400 may be a laser diode or any other type of laser light source such as a gas laser. The laser light source 400 is fixedly supported in a support structure 402 attachable to the housing 11. The laser conditioning optics 68 are attached to a cylindrical extension 404 of the support structure 402 that extends into the housing 11 as described relative to FIG. 3. An electro-optic beam deflection device 406 is disposed intermediate the laser light source 400 and the laser conditioning optics 68. The electro-optic beam deflection device 406 may be of any type known in the art that functionally acts in the same way as the physical displacement of the light source relative to the optical axis of the laser conditioning optics 68.
FIG. 5 depicts another arrangement for displacing the light beam emitted by a source of laser light. It is possible to implement the cross-scan correction by having a fixed laser source and using one or more lenses mounted to a piezoelectric actuator. A collimated (infinite conjugate) beam entering the lens (or lenses) 410 will be focused at an image plane 412. A piezoelectric actuator 414 will then shift the lens resulting in direct translation of the focused beam having the same displacement of that of the lens 410 as illustrated in FIG. 5. The diverging energy from the displaced focal point is collected by the laser conditioning optics 68 resulting in an angular shift in the beam when presented to the facets 56 of the rotating polygon scan optic 54 thus having the potential of correcting the cross-scan error as previously discussed.
FIG. 6 depicts yet another possible arrangement for displacing the light beam emitted by a source of laser light. A fixed focus (focal point) 420 is presented at one finite conjugate of a lens (or lenses) 416, encounters the lens, and is focused at the other side of the lens at an image plane 418. The translation of the lens 416 by a piezoelectric actuator 424 again results in translation of the focused light beam, and in combination with further beam conditioning optics, results in an angular shift of the beam presented to the facets 56 of the rotating polygon scan optic 54. The use of the lens (or lenses) 416 with two finite conjugate focal points 420 and 422 offers the ability to increase the magnification of the translation of the relayed focal point in accordance with the equation (f1+f2)/f1.
FIG. 7 illustrates the highly repeating nature of in-scan error for eight revolutions of an eight facet polygon scan optic connected to the shaft of the self-acting gas bearing according to the present invention.
FIG. 8 illustrates the improvement achieved by applying an appropriate correction to the highly repeatable in-scan errors.
FIG. 9 illustrates the highly repeating nature of cross-scan error for several revolutions of the polygon scan optic as it is rotated on a self-acting gas bearing according to the invention.
FIG. 10 illustrates the cross-scan error after correction is implemented.
The polygon optic device 50 is contrived so that it will produce very repeatable cross-scan errors that are no worse than 10-20 times that of the final system requirements. The polygon optic device also has a velocity feedback control system that controls the short-term incremental velocity of the rotational polygon scan optic 54 to less than 1/1,000,000 of a revolution between successive revolutions. The ability to correct both the in-scan and cross-scan errors is enabled by the use of the self-acting gas bearing 88, attention to aerodynamic streamlining of the polygon scan optic 54, and the use of a separate windowed enclosure for the polygon scan optic 54 so that short-term non-repeating sources of error are negligible.
The laser beam encounters successive facets of the rotating polygon scan optic 54, and emerges essentially free of cross-scan and in-scan trajectory errors. The scanned laser beam is then encountered by a post-scan flat mirror 18 that directs the laser beam to an f-theta correcting mirror 20 which corrects the f-theta curvature of the scanned beam and directs the beam toward a second flat mirror 22 that encounters the beam and directs it to the image plane where reprographic media or other objects are scanned. The flat mirrors 18 and 22 are used to compress and position the laser beam at the desired image plane and are not essential to the basic operating principles of the invention. A spherical or aspherical powered mirror may be used for the f-theta correcting mirror 20 depending on the required imaging resolution. Use of a powered mirror to influence f-theta correction results in nearly telecentric imaging performance. Many arrangements of flat mirrors, powered mirrors and the like are possible without departing from the present invention.
A separate conveyor or capstan roller transport mechanism 72, operating at a constant velocity, and which is not a part of the disclosed invention, is required to present the media 70 or any other object to be scanned to the disclosed polygon scanning system 10.
Fiber optic coupling of diode lasers is a commonly applied technique to produce a more refined Gaussian beam profile than is possible by direct imaging of the lasing element of the diode laser itself. Another variation of the invention is to mount the end of a fiber optic strand of a fiber coupled laser diode onto the end of an electro-mechanical linear actuator. Effectively, the source of laser light from the laser diode now undergoes the exact linear motion profile as that of the actuator without having to exert vibrational acceleration stresses on the laser diode itself as occurs in the embodiment illustrated in FIG. 3.
Another variation of the proposed invention is the attachment of the end of a fiber optic strand onto the end of an electro-mechanical actuator except that the laser light source that is coupled to the fiber optic strand may be gas laser. Significant power transmission, low inertia, high frequency response, and good beam quality are realized by use of a fiber coupled laser in the context of the disclosed invention and the means for cross-scan correction.
Variations of the beam conditioning subsystem may include fiber optic coupling of the laser diode or gas laser, fiber optic coupling of three lasers into common path collimating lenses, focusing lenses or reflecting optical elements to produce the desired beam quality, focal length, and other optical parameters typical of systems of this kind.
While the invention has been described in terms of a preferred embodiment with reference to several alternative embodiments, it should be apparent to one skilled in the art that variants and substitutes to the elements of the above described invention can be adopted without departing from the present invention. Accordingly, the scope of the present invention is to be limited only by the following claims. | A polygon scanner utilizing a fluid film bearing and method for its use in a flat field imaging device having a relatively large format size, a very high scan rate and high resolution. The polygon scanner has a polygon scan optic connected to a motor, a fluid film bearing, and a windowed enclosure. Repeating cross-scan error components are mapped and actively corrected using a piezoelectric actuator to directly displace the laser element or using a mirror in the optical path that is tilted by means of an electro-optic device to influence a virtual displacement of the optical beam. The repeating components of in-scan errors are similarly, and independently, mapped and corrected by summing with the output of a phase detector in a line scan speed control system. Methods for independently correcting the errors associated with cross-scan and in-scan components in the scan optic are significantly enhanced by the use of a fluid film bearing in general and a self-acting gas bearing in particular, supporting the rotating polygon scan optic. A method for periodic calibration of the cross-scan error map established at the factory may be implemented by a self-calibration sub-routine using a stored sinusoidal voltage waveform. This simplified calibration technique of the invention is enabled by the use of a fluid film bearing in general and a self-acting gas bearing in particular. | 7 |
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