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FIELD OF THE INVENTION
A subject-matter of the invention is a process for the preparation of fluorinated compounds, namely the fluorinated compound 2,3,3,3-tetrafluoro-1-propene.
TECHNOLOGICAL BACKGROUND
Hydrofluorocarbons (HFCs) and in particular hydrofluoroolefins, such as 2,3,3,3-tetrafluoro-1-propene (HFO-1234yf), are compounds known for their properties of refrigerants and heat-transfer fluids, extinguishers, propellants, foaming agents, blowing agents, gaseous dielectrics, polymerization medium or monomer, support fluids, agents for abrasives, drying agents and fluids for energy production units. Unlike CFCs and HCFCs, which are potentially dangerous to the ozone layer, HFOs do not comprise chlorine and thus do not present a problem for the ozone layer.
Several processes for the manufacture of 1234yf are known.
WO2008/002499 describes a process for the production of a mixture of 2,3,3,3-tetrafluoro-1-propene (HFO-1234yf) and 1,3,3,3-tetrafluoro-1-propene (HFO-1234ze) by pyrolysis of 1,1,1,2,3-pentafluoropropane (HFC-245eb).
WO2008/002500 describes a process for production of a mixture of 2,3,3,3-tetrafluoro-1-propene (HFO-1234yf) and 1,3,3,3-tetrafluoro-1-propene (HFO-1234ze) by catalytic conversion of 1,1,1,2,3-pentafluoropropane (HFC-245eb) over a dehydrofluorination catalyst.
These two abovementioned patent applications are thus targeted at the production of a mixture comprising a substantial portion of product HFO-1234ze.
WO2007/056194 describes the preparation of HFO-1234yf by dehydrofluorination of HFC-245eb either with potassium hydroxide, typically an aqueous solution of at most 50% by weight of KOH, or in the gas phase in the presence of a catalyst, in particular a catalyst based on nickel, carbon or a combination of these.
The document Knunyants et al., Journal of the USSR Academy of Sciences, Chemistry Department, “Reactions of Fluoroolefins”, report 13 , “Catalytic Hydrogenation of Perfluoroolefins”, 1960, clearly describes various chemical reactions on fluorinated compounds. This document describes the substantially quantitative hydrogenation of HFP over a catalyst based on palladium supported on alumina, the temperature changing from 20° C. to 50° C. and then being maintained at this value. This document describes the dehydrofluorination of 1,1,1,2,3,3-hexafluoropropane (HFC-236ea) by passing through a suspension of KOH in dibutyl ether, in order to produce 1,2,3,3,3-pentafluoro-1-propene (HFO-1225ye) with a yield of only 60%. This document describes the hydrogenation of 1,2,3,3,3-pentafluoro-1-propene (HFO-1225ye) to give 1,1,1,2,3-pentafluoropropane (HFC-245eb) over a catalyst formed of palladium supported on alumina. During this hydrogenation, a hydrogenolysis reaction also takes place, a significant amount of 1,1,1,2-tetrafluoropropane being produced. This document describes the dehydrofluorination of 1,1,1,2,3-pentafluoropropane (HFC-245eb) to give 2,3,3,3-tetrafluoro-1-propene (HFO-1234yf) by passing into a suspension of KOH powder in dibutyl ether, with a yield of only 70%. These reactions are described independently of one another even if it is indicated that it is possible to combine them in order to synthesize a range of ethylene, propylene and isobutylene derivatives comprising variable amounts of fluorine.
The document U.S. Pat. No. 5,396,000 describes the preparation of 1,1,1,2,3-pentafluoropropane by catalytic dehydrofluorination of 1,1,1,2,3,3-hexafluoropropane (HFC-236ea) to give 1,2,3,3,3-pentafluoro-1-propene (HFO-1225ye), followed by a hydrogenation in order to produce the desired compound. The dehydrohalogenation of HFC-236ea to give HFO-1225ye is carried out in the gas phase, the reaction product being, in one example, conveyed directly to the following reactor in which the hydrogenation of the compound HFO-1225ye to give the compound HFC-245eb takes place. It is also indicated in this document that the compound HFC-236ea can be obtained by hydrogenation of hexafluoropropylene (HFP).
The document U.S. Pat. No. 5,679,875 describes the preparation of 1,1,1,2,3-pentafluoropropane by catalytic dehydrofluorination of 1,1,1,2,3,3-hexafluoropropane (HFC-236ea) to give 1,2,3,3,3-pentafluoro-1-propene (HFO-1225ye), followed by hydrogenation to produce the desired compound. The reactions are carried out in the gas phase. It is also indicated in this document that the compound HFC-236ea can be obtained by hydrogenation of hexafluoropropylene (HFP).
The document WO 2008/030440 describes the preparation of HFO-1234yf from HFO-1225ye by reacting HFO-1225ye with hydrogen in the presence of a catalyst, in order to give HFC-245eb, and by then reacting the HFC-245eb with a basic aqueous solution in the presence of a phase transfer catalyst and a non-aqueous and non-alcoholic solvent.
The document WO 2008/075017 illustrates the dehydrofluorination reaction of 1,1,1,2,3,3-hexafluoropropane (HFC-236ea) to give 1,1,1,2,3-pentafluoropropene (HFO-1225ye) at 150° C. in the presence of a 50% by weight aqueous KOH solution. In the absence of a phase transfer catalyst, the conversion after 3 and a half hours is 57.8% and the selectivity for HFO-1225ye is 52.4% (Test 1). In the presence of a phase transfer catalyst, this conversion is achieved after only 2.5 hours and the selectivity is virtually unchanged (Test 4). As indicated in Table 2 of this document, it is necessary to use an organic solvent in order to increase the selectivity for HFO-1225ye.
There exists a need for a process for the preparation of 1234yf from a starting material which is easily accessible and which results in the desired product with a high selectivity, preferably a high yield and advantageously a high productive output.
SUMMARY OF THE INVENTION
The invention thus provides a process for the preparation of 2,3,3,3-tetrafluoro-1-propene which comprises the following stages:
(i) hydrogenation of hexafluoropropylene to give 1,1,1,2,3,3-hexafluoropropane; (ii) dehydrofluorination of the 1,1,1,2,3,3-hexafluoropropane obtained in the preceding stage to give 1,2,3,3,3-pentafluoro-1-propene using a water and potassium hydroxide mixture with the potassium hydroxide representing between 58 and 86% by weight of the mixture and at a temperature of between 110 and 180° C.; (iii) hydrogenation of the 1,2,3,3,3-pentafluoro-1-propene obtained in the preceding stage to give 1,1,1,2,3-pentafluoropropane; (iv) dehydrofluorination of the 1,1,1,2,3-pentafluoropropane obtained in the preceding stage to give 2,3,3,3-tetrafluoro-1-propene using a water and potassium hydroxide mixture with the potassium hydroxide representing between 58 and 86% by weight of the mixture and at a temperature of between 110 and 180° C.
According to embodiments:
the hydrogenation stages (i) and (iii) are carried out in the same reactor, preferably with the same catalyst, a separation stage optionally being present; the hydrogenation stages (i) and/or (iii) are carried out in a multistage reactor or in at least two reactors in series, a separation stage optionally being present; the dehydrofluorination stages (ii) and/or (iv) are carried out in at least two reactors in series, the separation stage optionally being present; the stream from stage (i) comprising the 1,1,1,2,3,3-hexafluoropropane is conveyed directly to stage (ii) without separation of the reactants; the stream from stage (i) comprising the 1,1,1,2,3,3-hexafluoropropane is conveyed to stage (ii) after separation of the unreacted reactants, which are optionally recycled to stage (i); the stream from stage (ii) comprising the 1,2,3,3,3-pentafluoro-1-propene is conveyed to stage (iii) after a purification stage; the stream from stage (iii) comprising the 1,1,1,2,3-pentafluoropropane is conveyed directly to stage (iv) without separation of the reactants; the stream from stage (iii) comprising the 1,1,1,2,3-pentafluoropropane is conveyed to stage (iv) after separation of the unreacted reactants, which are optionally recycled to stage (iii).
DETAILED DESCRIPTION OF EMBODIMENTS
The invention uses four reactions in series, the reaction products being conveyed to the following stage, optionally after having been subjected to a treatment, for example a separation treatment, if need be.
It is possible to provide for feeding the following stage in part with reactants not originating from the preceding stage.
In the process, the reaction stages are carried out batchwise, semi-continuously or continuously. Advantageously, the process according to the present invention is carried out continuously. An economical process for the preparation of the compound HFO-1234yf is thus obtained, the starting material HFP being easily available commercially at a low cost.
The hydrogenation stages are carried out conventionally for a person skilled in the art. A person skilled in the art can choose the operating conditions in order for the reactions to be substantially quantitative.
The catalysts capable of being used in these reactions are those known for this purpose. Mention may in particular be made of catalysts based on a metal from Group VIII or rhenium. This catalyst may be supported, for example on carbon, silicon carbide, alumina, aluminium fluoride and the like, or may not be supported, such as Raney nickel. Use may be made, as metal, of platinum or palladium, in particular palladium, advantageously supported on carbon or alumina. It is also possible to combine this metal with another metal, such as silver, copper, gold, tellurium, zinc, chromium, molybdenum and thallium. These hydrogenation catalysts are known.
The catalyst can be present in any appropriate form, for example the form of a fixed or fluidized bed, preferably as fixed bed. The stream direction can be from the top downwards or from the bottom upwards. The catalyst bed can also comprise a specific distribution of the catalyst in order to manage the flow of heat generated by the exothermic reaction. Thus, it is possible to provide gradients in density of loading, in porosity, and the like, of the catalyst in order to regulate the exothermicity of the reaction. For example, it is possible to provide for the first part of the bed to comprise less catalyst, while the second part comprises more thereof.
It is also possible to provide stages for regeneration of the catalyst in a known way.
It is also possible to provide for the use of a diluting gas, such as nitrogen, helium or argon.
The hydrogenation stages are exothermic. The reaction temperature can be controlled using means positioned for this purpose in the reactor, if need be. The temperature can vary by a few tens of degrees during the reaction, the reaction (i) being more exothermic than the reaction (iii). For example, the inlet temperature can vary from 20° C. to 120° C., preferably between 50 and 100° C., and the increase in temperature can vary from 5° C. to 100° C.
The contact time (ratio of the catalyst volume to the total stream of the charge) is generally between 0.1 and 100 seconds, preferably between 1 and 50 seconds and advantageously between 2 and 10 seconds.
The amount of hydrogen injected can vary within wide limits. The H 2 /charge ratio can vary within wide limits, in particular between 1 (the stoichiometric amount) and 30, in particular between 1.5 and 20, advantageously between 1.1 and 3. A high ratio will result in a dilution and thus in better management of the exothermicity of the reaction.
The stream resulting from the hydrogenation stages (i) and/or (iii) can be conveyed directly to the following dehydrofluorination stage or can be subjected to a separation stage in order to separate the unreacted reactants (hydrogen, HFP or HFO-1225ye) before being conveyed to the following dehydrofluorination stage. After separation, the unreacted reactants can be recycled.
Preferably, the stream resulting from the hydrogenation stages (i) and/or (iii) is or are conveyed directly to the following dehydrofluorination stage.
The hydrogenation reactions of stage (i) and/or (iii) are preferably substantially quantitative. They can be carried out in a multistage reactor or in at least two reactors in series, a separation stage optionally being present.
The dehydrofluorination reactions are carried out by reacting HFC-236ea and/or HFC-245eb with a water and potassium hydroxide (KOH) mixture in which the potassium hydroxide is present at between 58 and 86% by weight at a temperature of between 110 and 180° C., preferably of greater than 150° C. and advantageously of between 152 and 165° C.
Preferably, the potassium hydroxide is present at between 60 and 75% in weight in the water-KOH mixture.
The water and KOH mixture used can originate from hydrates of formula KOH.xH 2 O (x being between 1 and 2). Preferably, the dehydrofluorination reactions are carried out in the presence of these potassium hydroxide hydrates in the molten state and advantageously in the absence of solvent and/or of phase transfer catalyst.
The 1,1,1,2,3,3-hexafluoropropane in stage (ii) and/or the 1,1,1,2,3-pentafluoropropane in stage (iv) is or are converted generally to more than 90%, preferably to more than 95% and advantageously to more than 98%.
A diluting gas (nitrogen, helium, argon or hydrogen) can be used in the dehydrofluorination reaction.
The dehydrofluorination reaction can be carried out in any type of reactor known to a person skilled in the art. Use may be made of a stirred reactor, a static mixer or a reactive column or the HFC-236ea and/or the HFC-245eb can very simply be sparged into the water and KOH mixture in a vessel. Use may also be made of at least two reactors in series.
The amount of KOH involved in the dehydrofluorination reactions, when they are carried out batchwise or semi-continuously, is such that the KOH/HFC-245eb or HFC-236ea molar ratio is between 1 and 20.
During the dehydrofluorination reactions, potassium fluoride is formed and, for reactions carried out continuously, it is preferable to remove from the reaction medium, continuously or batchwise, all or a portion of the KF formed. The potassium fluoride can be separated from the reaction medium by filtration.
During the dehydrofluorination reactions, water is formed and can also be removed continuously or batchwise so as to maintain the KOH content in the water-KOH mixture within the interval described above. Removal of water can be carried out by evaporation.
The stream resulting from the dehydrofluorination stage (ii) comprising the HFO-1225ye can be conveyed directly to stage (iii). Preferably, this stream is purified beforehand, for example by distillation.
The stream resulting from the dehydrofluorination stage (iv) comprising the HFO-1234yf, optionally separated from the HFC-245eb, is subjected to a stage of purification, for example by distillation.
It is possible, in the process, to provide for the hydrogenation stages (i) and (iii) to be carried out in the same reactor, preferably with the same catalyst.
The cohydrogenation is carried out in a first reactor, the outlet stream of which comprises HFC-236ea and HFC-245eb. The outlet stream can be separated and the HFC-236ea is conveyed to a first dehydrofluorination reactor while the HFC-245eb is conveyed to a second dehydrofluorination reactor. The outlet stream from the first dehydrofluorination reactor predominantly comprises HFO-1225ye and optionally unreacted HFC-236ea. The outlet stream from the first dehydrofluorination reactor can be conveyed back to the hydrogenation reactor, thus producing the compound HFC-245eb from this HFO-1225ye. The HFC-236ea possibly separated can be recycled to the top of this dehydrofluorination reactor.
The pressure in the various reactions can be atmospheric or lower than or greater than this atmospheric pressure. The pressure can vary from one reaction to another, if appropriate.
Feeding with reactants generally takes place continuously or can be sequenced, if appropriate.
The reactions are carried out in one or more reactors dedicated to reactions involving halogens. Such reactors are known to a person skilled in the art and can comprise internal coatings based, for example, on Hastelloy®, Inconel®, Monel® or fluoropolymers. The reactor can also comprise heat exchange means, if necessary.
It should be remembered that:
the degree of conversion is the % of the starting material which has reacted (number of moles of starting material which have reacted/number of moles of starting material introduced); the selectivity for desired product is the ratio of the number of moles of desired product formed to the number of moles of starting material which have reacted; the yield of desired product is the ratio of the number of moles of desired product formed to the number of moles of starting material introduced, it being possible for the yield of desired product also to be defined as the product of the conversion and of the selectivity; the contact time is the inverse of the space velocity WHSV; the space velocity is the ratio of the flow rate by volume of the total gas stream to the volume of the catalytic bed, under standard temperature and pressure conditions.
EXAMPLES
The following examples illustrate the invention without limiting it.
Example 1
Hydrogenation of HFP to Give HFC-236ea
Use is made of a jacketed tubular reactor with an internal diameter of 21 mm and a length of 1.2 m, with circulation of water maintained at 40° C. The reactor is charged with three catalytic beds of the type comprising pellets of Pd supported on alumina. The three catalytic beds differ in the content of the supported Pd and are arranged in increasing concentration. The catalytic bed having the lowest Pd content is found closest to the inlet for the reactants.
Thus, the reactor comprises a bed of 15 cm composed of catalyst having a content of Pd of 0.5% by weight on alumina but diluted with 5 times the volume of silicon carbide, a bed of 10 cm composed of catalyst having a content of Pd of 0.5% by weight on undiluted alumina and a bed of 20 cm of catalyst having a content of Pd of 2.2% by weight on alumina.
Before charging the three catalytic beds, approximately 130 cm 3 of corundum (i.e. 37 cm) were introduced into the reactor. 80 cm 3 of corundum (25 cm) were also introduced above the first catalytic bed.
The catalyst is activated using a stream of approximately 20 l/h of hydrogen at 250° C. for 12 h before it is first brought into service.
The pressure is 1 bar absolute.
With an HFP flow rate of 150 g/h (1 mol/h) and a hydrogen flow rate of 33.6 Sl/h (1.5 mol/h) and with complete conversion of HFP, a yield of HFC-236ea of 95.2% is obtained.
During the reaction, a maximum temperature of 105° C. was observed for the most dilute catalytic bed and a maximum temperature of 140° C. was observed for the other two catalytic beds.
Example 2
Dehydrofluorination of HFC-236ea to Give HFO-1225ye
Use is made of two vessels with a volume of 1 litre connected in series (the gas stream resulting from the first vessel is used to feed the second vessel) and 1000 g of water and KOH mixture in which the KOH is present at 80% by weight are charged to each vessel. The temperature of the mixture is maintained between 155 and 170° C. 165 g/h of HFC-236ea are continuously introduced for 6 hours. For complete conversion of HFC-236ea, a yield of HFO-1225ye of 93.9% is obtained.
Example 3
Hydrogenation of HFO-1225ye to Give HFC-245eb
Use is made of the same reactor as in Example 1 but with a catalytic charge comprising a bed of 23.5 cm of catalyst comprising 0.2% by weight of Pd on silicon carbide (SiC), a bed of 15 cm of catalyst comprising 0.5% by weight of Pd supported on charcoal and a bed of 40 cm of catalyst comprising 2.0% by weight of Pd on charcoal. The temperature of the water in the jacket is maintained at approximately 85° C. The pressure is 1 bar absolute.
For an HFO-1225ye flow rate of 128 g/h and a hydrogen flow rate of 33.6 Sl/h and with complete conversion, a yield of HFC-245eb of 84% is obtained.
Example 4
Dehydrofluorination of HFC-245eb to Give HFO-1234yf
Use is made of a vessel with a volume of 1 litre comprising 1000 g of a water and KOH mixture in which the KOH is present at 75% by weight. HFC-245eb is introduced continuously into the mixture, maintained at 160° C., for 2 hours with a flow rate of 138 g/h and a conversion of HFC-245eb of 83% is obtained for a selectivity for HFO-1234yf of 100%. The pressure is 1 bar.
Example 5
Use is made of the device of Example 3 with the same catalytic composition, except that the stream at the outlet of the hydrogenation reactor is introduced directly into the water and KOH mixture of the device of Example 2 comprising, in the first reactor, 850 g of water and KOH mixture in which the KOH is present at 80% by weight and, in the second reactor, 637 g of the same mixture.
2.79 mol/h of hydrogen and 1.04 mol/h of HFP are introduced continuously into the hydrogenation reactor for 5.1 hours and, after passing into the reactors comprising the water and KOH mixture, complete conversion of HFP and a yield of HFO-1225ye of 92% are obtained.
Example 6
Use is made of the same device as in Example 5, except that one mol/h of unpurified HFO-1225ye obtained in Example 5 and 1.5 mol/h of hydrogen are introduced continuously for 6.4 hours. For a conversion of HFO-1225ye of 98%, a yield of HFO-1234yf of 96.8% is obtained. | A subject-matter of the invention is a process for the preparation of 2,3,3,3-tetrafluoro-1-propene which comprises the following stages: (i) hydrogenation of hexafluoropropylene to give 1,1,1,2,3,3-hexafluoropropane; (ii) dehydrofluorination of the 1,1,1,2,3,3-hexafluoropropane obtained in the preceding stage to give 1,2,3,3,3-pentafluoro-1-propene; (iii) hydrogenation of the 1,2,3,3,3-pentafluoro-1-propene obtained in the preceding stage to give 1,1,1,2,3-pentafluoropropane; and (iv) dehydrofluorination of the 1,1,1,2,3-pentafluoropropane obtained in the preceding stage to give 2,3,3,3-tetrafluoro-1-propene. Stages (ii) and (iv) are carried out using a water and potassium hydroxide mixture with the potassium hydroxide representing between 58 and 86% by weight of the mixture and at a temperature of between 110 and 180° C. | 8 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] This invention is directed to a hydraulic fracturing system and method for enhancing an effective permeability of low permeability earth formations to increase hydrocarbon production, enhance operation efficiency by reducing fluid entry friction due to tortuosity and perforation, and to open perforations that are either unopened or not effective using traditional perforating techniques including techniques utilizing shaped explosive charges, as well as reducing entry friction in slotted pipe during multi stage hydraulic fracturing operations.
[0003] 2. Discussion of Related Art
[0004] Hydraulic fracturing is a method of extracting hydrocarbons from earth formations in which thousands of gallons of a fracturing fluid, generally water, proppants, and other chemicals, are injected into a wellbore and a surrounding earth formation. The high pressure creates fractures in the earth formation, along which hydrocarbons, such as gas and petroleum, may flow to the wellbore and collected therefrom. However, this basic hydraulic fracturing method is unable to extract a maximum amount of hydrocarbons. Generally, after an initial fracturing operation, pumping continues to cause deepening and widening of the fissures by injection of more fluid. While it is generally desirable to open a plurality of fractures in a selected stratum, the basic process is only capable of creating a few fractures at most. When an incipient fracture begins to open, the fracturing fluid enters this new space and the pressure in the wellbore and fractures decreases reducing the tendency to open new fractures. This phenomenon limits the results of the basic fracturing process.
[0005] Other known hydraulic fracturing processes attempt to improve the process described above by adding a hammer effect to transmit a relatively large hydraulic shock against the formation to be fractured. For example, U.S. Pat. No. 2,915,122 to Donald S. Hulse and U.S. Pat. No. 3,048,226 to E. W. Smith. Other known hydraulic fracturing processes use a series of pressure pulses to improve the typical fracturing process. For example, U.S. Pat. No. 3,602,311 to Norman F. Whitsitt and U.S. Pat. No. 3,933,205 to Othar Meade Kiel. However, these known processes generally effect only a small number fractures radiating from the wellbore and may cause damage to piping and equipment.
[0006] Other known hydraulic fracturing techniques attempt to overcome the issue of reduced pressure due to newly opened fractures by blocking the newly formed fractures to allow a return to the initial pressure to allow additional fractures to be created. These methods include using degradable and/or non-degradable ball sealers that enter newly opened perforations to restrict flow of fracturing fluid into the opened perforations, thus forcing the fracturing fluid to open new perforations and to create new fractures. Ball sealers land on the newly opened perforations until a complete ball-out is achieved, where all possible perforations are opened and then sealed with a ball. At this point, no more flow is possible and the ball sealers have to be removed by flowing the well back, or in the case of using degradable balls, a long period is needed to allow for the balls to dissolve. These techniques are not practical in long horizontal wells where 100 or more perforation clusters are used to stimulate the long horizontal well. Furthermore, the wait time for the degradable ball sealers to dissolve would render the operations uneconomical.
[0007] As such, there is a need for an improved hydraulic fracturing process that provides an increased hydrocarbon production without the shortcomings of the known processes.
SUMMARY OF THE INVENTION
[0008] It is one object of this invention to provide a system and method for providing a pressure pulse to a wellbore to improve fracturing of an earth formation to provide increased hydrocarbon production.
[0009] It is another object of this invention to provide the pressure pulse and minimizes or eliminates wear or damage to a fracturing pump and/or other fracturing equipment.
[0010] These and other benefits can be provided by an embodiment of this invention which includes one or more of a fracturing fluid storage tank, a pre-blender, a slurry-blender, a proppant storage and delivery system, a manifold, a high-pressure fracturing pump, a chemical truck, a flow line connected to a wellhead of a wellbore, a bleed-off valve and a bleed-off line connected to a pit. Alternative embodiments of this invention may be created without one or more of the listed components and may include additional components.
[0011] In a preferred embodiment, the fracturing tank supplies a primary component of a fracturing fluid and/or a fracturing slurry, each of which preferably comprise water. However, other fluids, gels and other materials may be used as the primary component of the fracturing fluids and/or fracturing slurry. The fracturing tank is connected to the pre-blender, for example, a mixing truck that also connects with a chemical truck, and mixes the water, polymer and other chemicals to make the fracturing fluid (without a proppant). The pre-blender connects to the manifold and/or the slurry-blender to provide either the fracturing fluid or the fracturing slurry to the high-pressure fracturing pumps. The slurry-blender is connected to the proppant storage and delivery system to create the fracturing slurry by mixing the fracturing fluid with the proppant. The slurry-blender connects to the manifold. The manifold receives the fracturing fluid, with or without proppant, at a low pressure from the pre-blender or the slurry-blender and distributes the fluid and/or slurry to the high-pressure fracturing pumps. The manifold then receives the fluids at a high pressure from the high-pressure fracturing pumps and directs the fluid to a ground iron leading to the wellhead and the wellbore.
[0012] The high-pressure fracturing pump pumps the fracturing fluid, with or without proppant, to the wellhead at a pump rate through a flow line. In a preferred embodiment, the flow line comprises a plurality of pipes which connect the high-pressure fracturing pumps, through a single or multiple common manifolds, to a wellhead of the wellbore. In an embodiment of this invention, the plurality of flow lines comprise at least one constant-flow flow line and at least one variable-flow flow line which includes the bleed-off valve and the bleed-off line. The constant-flow line supplies a first percentage of a flow rate supplied by the high-pressure fracturing pump to the wellhead. The flow rate of the constant-flow line preferably does not vary significantly. The variable-flow line supplies a second percentage of the flow rate supplied by the high-pressure fracturing pump to the wellhead. In a preferred embodiment, the flow rate of the variable-flow line can be varied by diverting a portion of the fracturing fluid via the bleed-off valve to a pit, tank, another wellhead and wellbore, or to any other holding device. In an alternative embodiment, the flow line may comprise a single pipe connected to the wellhead with a bleed-off line and without the constant-flow line.
[0013] In operation, a method of hydraulic fracturing stimulation according to one embodiment of this invention includes pumping the fracturing fluid, with or without the proppant, at a pump rate and injecting the fracturing fluid under pressure into the wellhead at an initial flow rate and creating small fractures in deep rock formations. As the system moves towards an equilibrium pressure with few or no new fractures being created and/or a fracture network complexity is no longer increasing, the method of this invention includes introducing a pressure pulse into the wellbore for a pulse period of time causing a temporary increase of pressure leading to opening new fractures. The pressure pulse comprises changing the initial flow rate to a pulse flow rate and then to a secondary flow rate. In embodiments of this invention, the pulse flow rate is less than the initial flow rate, ranging from 10% lower to nearly 100% lower, and the secondary flow rate is equal to the initial flow rate. In preferred embodiments, the pulse flow rate may range from 25% to 75% lower that the initial flow rate. More preferably, the pulse flow rate is 50% lower than the initial flow rate. In another embodiment of this invention, the pulse flow rate is ideally dropped to zero, however a zero flow rate may not be practical because of limitations on the equipment and/or because a zero flow rate will cause proppant transport issues and may damage equipment. In alternative embodiments, the pulse flow rate may be greater than the initial flow rate and/or the secondary flow rate may not equal the initial flow rate and may instead be greater than or less than the initial flow rate. In an embodiment of this invention, the pulse period of time is less than one minute. In a preferred embodiment of this invention, the pulse period of time is less than 10 seconds.
[0014] In an embodiment of the method of this invention, the pressure pulse is introduced by diverting a portion of the fracturing fluid away from the wellbore to provide a reduced flow rate to the wellbore for the pulse period of time. In this embodiment, the pump rate of the high-pressure fracturing pump remains constant so as to avoid placing additional stress on the high-pressure fracturing pump. In a preferred embodiment, the step of introducing the pressurized pulse comprises a plurality of pressurized pulses.
[0015] In an alternative embodiment, the pressure pulse is introduced by changing the pump rate of a fracturing pump from the pump rate to the pulse pump rate and back to the pump rate. Preferably, the pulse pump rate is less than the pump rate. Alternatively, the pulse pump rate is greater than the pump rate.
[0016] In another alternative embodiment, the pressure pulse includes increasing the initial flow rate to a pre-pulse flow rate, rapidly dropping the flow rate to a pulse flow rate and returning the flow rate to the pre-pulse flow rate and repeating this cycle for a number of times before returning the flow rate to the initial flow rate. This approach may be done by increasing and decreasing the pump rate and/or by redirecting the flow of fracturing fluid to change the flow rate.
[0017] The invention provides an improved hydraulic fracturing process that provides increased hydrocarbon production without the shortcomings of known processes.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] These and other objects and features of this invention will be better understood from the following detailed description taken in conjunction with the drawings, wherein:
[0019] FIG. 1 is a schematic diagram of a wellbore.
[0020] FIG. 2 is a graph showing a pump rate and a surface treating pressure of a method of hydraulic fracturing according to an embodiment of this invention.
[0021] FIG. 3 is a graph showing a wellhead pump rate and a surface treating pressure of a method of hydraulic fracturing according to an embodiment of this invention.
[0022] FIG. 4 is a schematic diagram of a system for hydraulic fracturing according to an embodiment of this invention.
[0023] FIG. 5 is a graph showing a surface treating pressure and a wellhead pump rate where a portion of a total pump flow is diverted according to another embodiment of this invention.
[0024] FIG. 6 is a schematic diagram of a portion of a system for hydraulic fracturing according to an alternative embodiment of this invention.
[0025] FIG. 7 is a graph showing a first total flow rate to a first wellhead and a second total flow rate to a second wellhead in another embodiment of this invention.
DESCRIPTION OF PREFERRED EMBODIMENTS
[0026] Hydraulic fracturing stimulation is a method of enhancing an effective permeability of a low permeability formation by extending a wellbore in the formation and creating propped fractures that enable hydrocarbon production from vast amounts of reservoir and channeling the hydrocarbons back to the wellbore from which the hydraulic fractures emanate. FIG. 1 shows a schematic view of a horizontal wellbore 10 for a fracturing operation. In this representation, the wellbore 10 extends vertically downward into the earth until reaching a target reservoir 12 (e.g. gas shale) where the wellbore 10 extends generally horizontal at a slight upward angle. It should be noted that the wellbore 10 is representative and the system and method of this invention be used with any type of wellbore that is necessary to access an earth formation. Furthermore, the method of this invention will be described in connection with gas shale however, it should be understood that the method may also be used with tight gas, tight oil, coal seam gas and other earth formations requiring hydraulic fracture stimulation including but not limited to geothermal reservoirs.
[0027] In the embodiment of FIG. 1 , the wellbore 10 includes a conductor casing 14 , a surface casing 16 , an intermediate casing 18 and a production casing 20 . However, it should be understood that the method of this invention is not limited to the wellbore 10 of FIG. 1 and may be used with other types of wellbore configurations, including fracture stimulation of vertical or slant wellbores. FIG. 1 shows the wellbore extending into the earth including a surface layer, a salt water layer, a formation layer, and the gas shale layer. However, it should be understood that the system of this invention is not limited to this geologic formation and may be used with other geologic formations. It should also be understood, that the system and method of this invention may be used with a subterranean extraction process including, but not limited to, enhanced geothermal systems.
[0028] In a preferred embodiment of this invention, the wellbore 10 further includes a plurality of perforation clusters 22 . The industry standard is to perforate multiple sections of the horizontal or vertical wellbore usually in 3 or 4 short sections called perforation clusters, spaced a short distance apart. For example, if a 200 foot section of the reservoir is to be fracture stimulated, an approach would be to perforate four, 1 foot sections of the wellbore spaced 50 feet apart, resulting in 4 clusters of perforations that should create 4 or more individual fractures. However, any number of perforation clusters and/or spacing may be used. For example, long horizontal wells may include 120 or more perforation clusters.
[0029] A typical fracture treatment is designed to be pumped at a constant flow rate to a wellhead and a wellbore, where increasing pressure in the wellbore fractures the earth formation. The method of this invention involves changing the fracturing flow rate rapidly to impart a pressure pulse that can open unopened perforations by exceeding a perforation breakdown pressure.
[0030] In an embodiment of this invention, the pressure pulse is imparted by rapidly shutting off a fracturing pump 42 ( FIG. 4 ) and turning the fracturing pump 42 back on. Alternatively, the pressure pulse may be imparted by changing by rapidly increasing or decreasing a pressure of a pump rate of the fracturing pump 42 . These methods are preferably conducted with fracturing fluid which does not include proppant, however; the methods may also be conducted with the fracturing fluid with proppant, also known as a fracturing slurry.
[0031] FIG. 2 shows a graph showing an embodiment of this invention where a pump rate 70 is varied to impart a pressure pulse to the wellhead to cause a change (ΔP) in a surface treating pressure 72 . In this embodiment, the pump rate 70 starts at an initial pump rate 74 and rapidly dropped to pulse pump rate 76 before returning to the initial pump rate 74 , this cycle is preferably repeated a plurality of times. As shown in the upper plot, the surface treating pressure 72 increases until it reaches a plateau pressure 78 . When the pulse pump rate 76 is introduced, the surface treating pressure 72 follows by dropping in pressure and rapidly increasing to a second plateau pressure 80 . The second plateau pressure 80 is at lower pressure than the plateau pressure 78 . This change in pressure (delta P (ΔP)) shows the pressure drop in the surface treating pressure 72 is associated with opening of additional perforations and/or fractures in the formation. In the embodiment of FIG. 2 , the method of this invention starts without proppant in the fracturing fluid. As the method of this embodiment proceeds, a proppant concentration 82 in the fracturing fluid is increased.
[0032] In another embodiment as shown in FIG. 3 , the method includes changing a fracturing pump rate 100 from 90 barrels per minute (bpm) to approximately 45 bpm, and then rapidly bringing the rate back to 90 bpm. Note that the rates mentioned here are meant as examples of sudden substantial rate decrease for creating a pressure pulse and are not intended to be limiting. The pumping of fracturing fluid or slurry into the wellhead causes a surface treating pressure 110 increase in the earth formation. In FIG. 3 , the pump rate 100 is increased until it reaches an initial pump rate 102 , approximately 20 bpm. Beginning at point 1 , the pump rate 100 is increased to a pre-pulse pump rate 104 , approximately 90 bpm, and rapidly dropped to a pulse pump rate 106 , approximately 45 bpm, and returned to the pre-pulse pump rate 104 , approximately 90 bpm. In this embodiment, the pulse is repeated three times before returning to the initial pump rate 102 at point 2 . The pump rate 100 causes a treating pressure 110 in the wellbore. This embodiment was implemented to induce three pressure impulses 112 , however any number of pressure impulses may be used. In each successive pulse, when the pump rate 106 was brought back up to the pre-pulse pump rate 104 , the treating pressure 110 , the pressure impulse 112 , was lower, indicating that there was less friction in the system. This could only happen if additional flow channels have been opened, thus implying that previously unopened perforations have been opened or new fractures extending from perforations have been created. Delta P (ΔP) 114 shows the pressure drop in the treating pressure 110 of each the pressure impulses 112 associated with opening of additional perforations and/or fractures in this embodiment. The significance of this is that the method of this invention opens new perforations without physical flow diverters such as ball sealers or frac balls and doesn't cost anything extra to execute. However, strain is placed on the fracturing pumps while performing this kind of rapid pump rate change.
[0033] In a preferred embodiment of this invention, rather than rapidly increasing and/or decreasing the pump rate of the fracturing pumps or in addition to changing the pump rate, a portion of the fracturing fluid, with or without proppant, is diverted away from the wellhead, changing the flow rate, in order to provide a pressure pulse to the wellbore 10 . FIG. 4 shows a schematic representation of an embodiment of an overall system layout 30 of this invention for providing a pressure pulse to the wellbore 10 with or without changing the pump rate. The system 30 of this embodiment preferably includes a fracturing tank 32 , generally a water tank, to store the water and/or other fluid that will comprise a portion of the fracturing fluid. The system 30 preferably also includes a pre-blender 34 , preferably a mixing truck that mixes the water or other fluid from the fracturing tank with other components of the fracturing fluid such as polymers and other chemicals to make the fracturing fluid. At this point, the fracturing fluid preferably does not include a proppant. The system of this invention further includes a slurry-blender 36 that mixes the fracturing fluid with the proppant and/or other chemicals to create a fracturing slurry. The proppant is stored in a proppant storage and delivery system 38 prior to mixing in the slurry-blender 36 . The system of this invention preferably further includes a manifold 40 that receives a fracturing slurry from the slurry-blender at a low pressure and distributes to a high-pressure fracturing pump 42 . The high-pressure fracturing pump 42 returns the fracturing fluid, with or without the proppant, to the manifold 40 at a high-pressure and to a flow line 44 to a wellhead 46 connected to the wellbore 10 . In a preferred embodiment, the system 30 further includes a chemical truck 48 which supplies chemicals to at least one of the pre-blender 34 and the slurry-blender 36 .
[0034] In a preferred embodiment, the system of this invention includes a plurality of flow lines 44 to the wellhead 46 . Preferably, at least one of the flow lines 44 is a variable-flow flow line 58 that is connected to a bleed-off line 50 connected to a pit 52 or some other type of storage, open or enclosed, or to another wellhead. While at least another one of the flow lines 44 is a constant rate flow line 60 . In operation, the high-pressure fracturing pump 42 supplies the fracturing fluid or the initial fracturing fluid to the flow lines 44 at a constant pressure and the constant-flow line 60 supplies a first percentage of the flow rate supplied by the high-pressure fracturing pump to the wellbore and the variable-flow line 58 supplies a second percentage of the flow rate supplied by the high-pressure fracturing pump. In a preferred embodiment, the flow rate supplied by the constant-flow line 60 does not change during the pressure pulse, while the flow rate supplied by the variable-flow line 58 changes during the pressure pulse. A bleed-off valve 54 in the bleed-off line 50 connected to the variable-flow line 58 can be opened and closed to divert a portion of the fluid from the wellhead 46 to provide the pressure pulse to the wellhead 46 . For example in FIG. 5 , two flow lines are used to supply a wellhead pump rate 90 , for example a total flow rate of 90 barrels per minute (bpm), to the wellhead 46 . In this embodiment, the constant-flow line 60 and the variable-flow line 58 each supply a percentage of the total flow (F 1 +F 2 ) for example the constant flow line supplies a constant flow rate 92 of 50% of the total flow, equaling 45 bpm, and the variable flow line supplies a variable flow rate 94 of 50% of the total flow, equaling 45 bpm. A pressure pulse is induced by allowing the constant-flow line F 2 to continue supplying the 45 bpm and redirecting the flow F 1 of the variable-flow line 58 away from the wellhead 46 for a short period of time into the pit 52 . For example, the short period of time may range from 1 minute to 1 second. Preferably, the short period of time equals 10 seconds. Alternatively, any period of time may be used. By redirecting the flow for the short amount of time, the method simulates the case where some of the pumps are being shut down (one half of the pumps in the example case), inducing a pressure impulse in a surface treating pressure 96 . As shown in FIG. 5 , when the bleed-off valve was closed and the wellhead pump rate was returned to the truck pump rate, the surface treating pressure 96 is lower than the initial treating pressure, Delta P (ΔP) 98 , indicating that there was less friction in the system. This could only happen if additional flow channels have been opened, thus implying that previously unopened perforations have been opened or new fractures extending from perforations have been created. The significance of this is that the method of this invention opens new perforations without physical flow diverters such as ball sealers or frac balls and does not require the truck pump rate to change. Please note the flow rates and times in the above example are exemplary and may be varied depending on the requirements of the wellbore and the earth formation.
[0035] In the embodiment of FIG. 5 , the method of this invention starts without proppant in the fracturing fluid. As the method of this embodiment proceeds, a proppant concentration 82 in the fracturing fluid is increased. Alternatively, the entire process may be conducted with or without the proppant.
[0036] In an alternative embodiment, one or more of the flow lines 44 may include a valve, not shown, that can be opened and closed to restrict a flow of fluid to the wellbore 10 to provide the pressure pulse.
[0037] In another embodiment of this invention, partially shown in FIG. 6 , the system includes a pair of wellheads 202 , 204 each connected to a wellbore 206 , 208 . A plurality of flow lines 210 connect to the wellheads 202 , 204 . In this embodiment, each of the wellheads include a constant rate flow line 212 , 214 and a diverter line 216 which is connected to both of the wellheads 202 , 204 . Each of the lines 212 , 214 , and 216 preferably connects to a system, not shown, for providing a pressure flow rate to the wellheads 202 , 204 , such as the system shown in FIG. 4 . In the embodiment of FIG. 6 , each of the wellheads 202 , 204 includes a separate constant flow rate line 212 , 214 and the wellheads 202 , 204 share the diverter line 216 with one or more valves 218 , 219 . In operation, the high-pressure fracturing pump, not shown, supplies the fracturing fluid or the fracturing slurry to the flow lines 210 at a constant flow rate. A first percentage of the flow rate passes through the first constant rate flow line 212 , a second percentage of the flow rate passes through the second constant flow rate line 2014 , and a third percentage of the flow rate passes the diverter line 216 . In a preferred embodiment, the flow rate supplied by each of the constant rate flow lines 212 , 214 does not change during the pressure pulse. While the flow rate supplied by the diverter line 216 is diverted to each of the wellheads 202 , 204 during the pressure pulse. For example in FIG. 7 , the high-pressure fracturing pump provides a first total flow rate 220 to the first wellhead 202 and a second total flow rate 230 to the second wellhead 204 . Initially, both valves 218 are open allowing the third percentage of the flow rate to be provided to both of the wellheads 202 , 204 . A pressure pulse 222 , 232 is induced by closing one of the valves 219 , increasing the total flow rate 220 to the first wellhead 202 and decreasing the total flow rate 230 to the second wellhead 204 for a short period of time. For example, the short period of time may range from 1 minute to 1 second. Preferably, the short period of time equals 10 seconds. Alternatively, any period of time may be used. The process is then repeated by closing the valve 218 , increasing the total flow rate 230 to the second wellhead 204 and decreasing the total flow rate 220 to the first wellhead 202 for a short period of time. With this system, the fracturing fluid is conserved and not diverted to a pit.
[0038] In operation, one or more methods of this invention impart a flow rate change in the fracturing fluid flow that is preferably at least 10% below an original wellhead treatment rate, all the way to 0 (zero) rate. In a preferred embodiment, the flow rate change ranges from 25% to 75% lower and more preferably changes by 50%. Furthermore, the pressure impulse has a duration ranging from 1 minute to 1 second. Alternatively, the pressure impulses can be induced by increasing the flow rate change.
[0039] Multiple rate reductions can be executed during any part of the fracturing process. In a preferred embodiment, the method of this invention the rate reduction, pressure pulse, is least risky and potentially most effective in a pad stage, i.e. a stage of providing the fracturing fluid without the proppant. Performing these rapid, large flow rate variations and/or pump rate variations, especially reductions, in the pad stage presents the least amount of risk because there is no proppant in the equipment, the wellbore and the formation that can settle out or bridge during rate reductions as rate reductions decrease the fluid velocity and in turn decrease the fluids' proppant transport capabilities. The rate variations are also potentially more effective in the pad stage as they open new perforations and then the proppant-less fluid is able to extend the newly created fracture before proppant has a chance to bridge off and potentially close it.
[0040] Thus, the invention provides an improved hydraulic fracturing process that provides increased hydrocarbon production without the shortcomings of known processes.
[0041] It will be appreciated that details of the foregoing embodiments, given for purposes of illustration, are not to be construed as limiting the scope of this invention. 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, which is defined in the following claims and all equivalents thereto. Further, it is recognized that many embodiments may be conceived that do not achieve all of the advantages of some embodiments, particularly of the preferred embodiments, yet the absence of a particular advantage shall not be construed to necessarily mean that such an embodiment is outside the scope of the present invention. | A hydraulic fracturing system and method for enhancing effective permeability of earth formations to increase hydrocarbon production, enhance operation efficiency by reducing fluid entry friction due to tortuosity and perforation, and to open perforations that are either unopened or not effective using traditional techniques, by varying a pump rate and/or a flow rate to a wellbore. | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority from German National Patent Application No. DE 10 2016 001 164.5, filed Feb. 2, 2016, entitled “Verfahren and Vorrichtung zum Betreiben einer Arbeitsstelle einer fadenballonbildenden Textilmaschine”, the entire contents of which are incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The present invention concerns a method or a device for operating a workstation of a yarn balloon forming textile machine, wherein a yarn balloon formed by a continuous yarn circling a spindle of the workstation is scanned with a sensor means at said workstation.
[0003] The method or the device according to the invention in particular serve for maintaining a stipulated diameter of a yarn balloon formed by a continuous yarn at a workstation of a yarn balloon forming textile machine.
BACKGROUND OF THE INVENTION
[0004] Various embodiments of production machines, where a yarn balloon is formed in the area of their often numerous workstations or at associated operating means during operation, have been known for a long time within the textile machine industry.
[0005] Such production machines therefore often comprise monitoring means for detecting and limiting the size of these yarn balloons, which can work very differently. Known monitoring means for example often include sensor means with which the circulating yarn, which forms the yarn balloon, is monitored.
[0006] A method and a device with which the yarn extraction speed from feed packages at the creel of a warping machine are optimised are for example described in German Patent Publication DE 101 03 892 A1.
[0007] A yarn balloon, the diameter of which will depend on the yarn extraction speed and the yarn pulling force amongst other things, is known to occur when a yarn is extracted overhead and at a relatively high extraction speed from a feed package positioned in an associated creel during the working process.
[0008] The size of the yarn balloon will grow with increasing yarn extraction speed.
[0009] With the method known from German Patent Publication DE 101 03 892 A1 the size of at least some of the yarn balloons created during yarn extraction is recorded and transmitted to a controller by measuring equipment arranged at the creel, will ensure that the regulation of the yarn extraction speed is acted upon when the limit values for the yarn balloons are reached.
[0010] Measuring equipment for recording the yarn balloon size can be various optically working measuring units, for example a camera, one or more light barriers or similar equipment.
[0011] As indicated above, the known method is used only for scanning the limit values for the balloon size, but provides no information about the balloon size at any time during the process. This means that a regulator not described in detail will be activated only when a stipulated limit value is exceeded or not reached, and is also deactivated when the stipulated values for the maximum extraction speed or the maximum yarn pulling force are reached.
[0012] Optically working measuring means working in connection with ring spinning machines are also known from German Patent Publication DE 22 55 663 A1 and European Patent Publication EP 0 282 745 A1, with which a yarn balloon shape and/or a yarn balloon size can be recorded.
[0013] German Patent Publication DE 22 55 663 A1 for example describes a workstation of a ring spinning machine equipped with an air or magnet mounted spinning ring, on which a spinning reel driven by the continuous yarn circulates.
[0014] As a specific difference between the speed of the spinning ring and the speed of the spinning reel is known to be necessary during operation of such workstations in order to guarantee a problem-free spinning process, the speed of the air or magnet mounted spinning ring as well as the speed of the spinning reel are checked during the spinning operation.
[0015] It is also continuously checked with this method whether a stipulated maximum yarn tension is maintained, and any yarn balloon created when spinning in the area of the spinning bobbin is checked and stabilised if necessary. This means that the expansion of the yarn curve of the yarn balloon is stabilised by measuring the yarn curve deviation of the yarn balloon from its meridian level and corresponding regulation of the yarn tension by means of variable braking of the spinning ring. The means for recording the yarn curve deviation of the yarn balloon here substantially consists of an encoder comprising a series of small photo elements as well as a trigger means that ensures that the yarn balloon is periodically illuminated.
[0016] The known devices are either relatively complicated (German Patent Publication DE 22 55 663 A1) and often also quite inaccurate, or they are very sensitive with regard to air pollution due to their large measuring range (German Patent Publication DE 101 03 892 A1).
[0017] In practice these known devices have thus not been able to prove themselves.
[0018] European Patent Publication EP 0 282 745 A1 describes a method or a device for the production and quality monitoring of workstations of a multi-spindle textile machine, which means a method and a device with which the presence of the yarns and yarn diameters are monitored.
[0019] A ring spinning machine is equipped with an optical monitoring organ for this purpose, which simultaneously checks a multitude of workstations of the textile machine arranged next to each other in series in that yarn balloons rotating in the area of the workstations are illuminated.
[0020] The monitoring organ comprises a transmitter and a receiver for this purpose, which are designed and arranged in such a way that a beam bundle emitted by the transmitter travels through the numerous circulating yarn balloons on its way to the receiver and is therefore intermittently interrupted or weakened by the yarn balloons.
[0021] This shading is converted into an electric signal in the receiver, which is used as the basis for further evaluation in an associated regulator.
[0022] The known method is used for detecting the presence of a yarn, or for monitoring the diameter of the yarn.
[0023] The method described in European Patent Publication EP 0 282 745 A1 does however occasionally work rather imprecisely, as the beam bundle is often negatively influenced by fiber and dust particles, which are almost unavoidable in the atmosphere of a spinning room, on its way from the transmitter to the receiver. The chosen arrangement of the monitoring organ also does not allow a conclusion with regard to the balloon diameters, and European Patent Publication EP 0 282 745 A1 does therefore contain no references to a regulator for maintaining a stipulated diameter of a yarn balloon either.
[0024] A workstation of a double-wire twisting and cabling machine, the quilling and winding means of which is arranged that it lies within a yarn balloon ruing operation, is also known from European Patent Publication EP 2 419 554 B1.
[0025] The workstation also comprises a monitoring means that can comprise various embodiments to be able to control the size of the yarn balloon. The monitoring means can for example work either indirectly or optically.
[0026] The size of the yarn balloon can for example be determined indirectly via a yarn tension sensor, which is arranged either between a yarn drive means and the inlet of the yarn into a spindle, which ensures the creation of the yarn balloon, or by means of a yarn tension sensor positioned between the outlet of the yarn from the spindle and a further yarn drive means.
[0027] In a further embodiment, recording the size of the yarn balloon can also be realised indirectly by measuring the performance or the torque of the drive means of the spindle. This means that the current absorbed by the spindle drive is determined with a measuring means and the size of the yarn balloon deduced from this in an evaluation means.
[0028] With regard to optical measuring means that monitor the yarn balloon circling the quilling and winding means, the use of at least two light barriers, comprising a light source for emitting a light beam and a light-sensitive detector for recording the light beam, is suggested in a first embodiment. With such a means the interruption of the light beam by the passing yarn of the yarn balloon is detected during operation. However, the known embodiment is used only for scanning the limit values for the balloon size and gives no exact indication of the size of the yarn balloon at any time of the spooling process.
[0029] In a further comparable embodiment a light sensor of the type CCD is used in combination with a beam-like, stroboscopic light source, for example an LED or laser.
[0030] With the means that acts with a light sensor and a stroboscopic light source synchronised by turning the spindle the image, and with it the shape of the yarn forming the yarn balloon, is localised when it is illuminated by the flash.
[0031] With such an embodiment different reflections are however possible, depending on the yarn thickness, yarn surface and/or yarn twists, which negatively influence the error quota and resolution of the measurement.
[0032] CCD receivers also represent extremely costly equipment, as they require a complex evaluation unit for their operation.
[0033] The monitoring means described in European Patent Publication EP 2 419 554 B1 in connection with a workstation of a double-wire twisting and cabling machine are all improvable, as they either do not measure precisely enough or are relatively costly.
[0034] A controller and regulator, with which it is monitored during operation at what angle an outer yarn enters into a torsion element of the workstation during the yarning operation, is also known from International PCT Patent Publication WO 2015/012773 A1 in connection with a workstation of a yarn machine. The torsion element then twists the outer yarn into a cord yarn with the inner yarn.
[0035] A method where the quality of a twisted yarn is monitored by an optoelectric measured value transducer comprising a light source and a light receiver is also known from European Patent Publication EP 0 638 674 B1.
[0036] With this known method a yarn circling in a relatively wide yarn guide means of optoelectric measured value transcoder with a circular movement, as is known in itself, generates signals by shading a light receiver, which are divided into a respective first and second signal by filtering.
[0037] The relevant degree of yearn twisted per time unit can then be determined for the respective yarn with an evaluation means from the first signal, whilst conclusions regarding the quality features of the yarn cab be drawn from the second signal.
SUMMARY OF THE INVENTION
[0038] Based on the above mentioned prior art the invention is based on the task of developing a method or a device with which the diameter of a yarn balloon formed by a continuous yarn can be determined, maintained, and possibly corrected at a workstation of a yarn balloon forming textile machine.
[0039] The method or the associated device should also be realised as simply and cost effectively as possible.
[0040] This tasks is solved according to the invention in that data recorded by the sensor means, which provides information about the current diameter of the tarn balloon to be monitored, is transmitted to a control circuit, in that the control circuit calculates the current actual diameter of the yarn balloon by means of this data and further known data, such as the speed of the spindle, compares this with a stipulated target diameter of the yarn balloon, and in that the control circuit ensures that the yarn balloon has the stipulated target diameter with the aid of a means switched into the yarn path of the yarn, for influencing the yarn tension.
[0041] Advantageous embodiments of the method according to the invention as well as device for implementing the method are more fully described hereinafter.
[0042] The method according to the invention in particular has the advantage that the diameter of the yarn balloon is monitored continuously from an adjustable minimum balloon size with a sensor means at every workstation of the yarn balloon forming textile machine, and corrected immediately when required by a control circuit that is connected to a means for influencing the yarn supply speed or the yarn tension of the yarn forming the yarn balloon in such a way that the yarn balloon always has a predeterminable, optimal diameter.
[0043] The construction elements necessary for implementing the method according to the invention are not only relatively cost effective, but also enable a compact construction of the workstation. This means that the space requirement of the yarn balloon forming textile machines working that comprise the workstations that work and are designed according to the invention is clearly less than the space requirement of yarn balloon forming textile machines in use to date.
[0044] The working method of the sensor means that monitors the yarn balloon is of no relevance in connection with the method according to the invention. This means that the sensor means used in connection with the method according to the invention can consist of various embodiments.
[0045] The sensor means can for example be designed as an optically working light barrier, comprising a light source as well as a light receiver, and equipped with a measuring beam designed as a light beam that monitors the circulating yarn balloon.
[0046] However, the sensor means does not need to work optically, as it is also possible to use a sensor means with a measuring beam that works on another base of the electromagnetic spectrum. The measuring beam can for example also be initiated by an ultrasound, induction, heat source etc. or its interferences, wherein a corresponding associated receiver is then also used.
[0047] In an advantageous embodiment it is envisaged that the control circuit controls the means for influencing the yarn supply speed or the yarn tension in such a way that the production speed of the workstation of the yarn balloon forming textile machine always remains high and constant outside of the start and stop phases of the workstation. This means the control circuit guarantees that the workstations of the yarn balloon forming textile machine will work at the highest possible production speed at all operating times when this is possible, which leads to a very good overall degree of effectiveness of the textile machine.
[0048] The control circuit preferably controls the means for influencing the yarn supply speed or the yarn tension in such a way that the yarn balloon already has the desired diameter during the start and stop phases of the workstation.
[0049] In this way it is ensured that the yarn balloon cannot hit components of its own workstation or components of a neighboring workstation at any time during the operation, which would certainly lead to the yarn breaking and thus to an interruption of the twisting process at the affected workstation.
[0050] In an advantageous embodiment it is envisaged in this regard that the control circuit controls the means for influencing the yarn supply speed or the yarn tension in such a way that the diameter of the yarn balloon is limited during the start and stop phases of the workstation in such a way that a yarn balloon that already has a minimum diameter is created.
[0051] Such an approach makes enables reducing the distance to the neighboring workstations of the textile machine.
[0052] A corresponding reduction of the distance of the workstations of the yarn balloon forming textile machine in turn enables a very compact construction of the textile machine, with the consequence that the space requirement of a textile machine that comprises the workstations designed and working according to the invention is clearly reduced.
[0053] The workstation with which the method according to the invention can be used preferably comprises a sensor means for scanning the diameter of the yarn balloon, a control circuit connected with the sensor means, and a means for influencing the yarn supply speed or the yarn tension of the yarn forming the yarn balloon, connected with the control circuit.
[0054] The circling yarn balloon causes shading at the sensor means, which is for example designed as a light barrier, during the twisting operation, from which the sensor means generates electric signals that are transmitted to the control circuit. The control circuit then calculates the current diameter of the yarn balloon from the time distance between two signals occurring during every yarn balloon circuit, and then with the aid of further known data.
[0055] In a case where the current actual diameter of the yarn balloon recorded by the sensor means does not equal the stipulated target diameter the means for influencing the yarn supply speed or the yarn tension connected with the control circuit comes into use. This means that the means ensures with the aid of corresponding corrections of the yarn supply speed or the yarn tension of the yarn forming the yarn balloon that the yarn balloon has the stipulated target diameter.
[0056] The yarn balloon forming textile machine with which the method according to the invention is preferably used, can consist of various kinds of textile machines or textile means.
[0057] The yarn balloon forming textile machine can for example be a double-wire twisting machine or a cabling machine, which for example produces cord yarns.
[0058] Use of the method according to the invention is however also of advantage with other textile machines, such as for example ring spinning machines.
[0059] The method according to the invention can also be used to advantage together with a warping machine or a warp creel.
[0060] In an advantageous embodiment the means connected to the control circuit for influencing the yarn supply speed and/or the yarn tension is a yarn supply means positioned before the yarn balloon in the yarn path. Such an outer yarn supply mechanism, for example switched in the yarn path of a cabling machine, enables in a precise and rapid influencing of the diameter of the yarn balloon simple way.
[0061] This means that an accurate adjustment of the target diameter of the yarn balloon is guaranteed at all times with such an outer yarn supply mechanism.
BRIEF DESCRIPTION OF THE DRAWINGS
[0062] The invention will now be described in more detail with reference to an embodiment illustrated in the drawings, wherein:
[0063] FIG. 1 is a schematic side view of a workstation of a double-wire twisting or cabling machine with a sensor means according to the invention, connected to a control circuit;
[0064] FIG. 2 is a control circuit for maintaining a target diameter of a yarn balloon monitored by the sensor means.
DETAILED DESCRIPTION OF THE INVENTION
[0065] A schematic side view of a workstation 1 of a double-wire twisting or cabling machine is shown in FIG. 1 , which comprises a creel 4 , as is usual, which is normally positioned above or behind the workstation 1 .
[0066] The creel 4 here serves for receiving at least one first feed package 7 , from which a so-called outer yarn 5 is extracted.
[0067] The workstation 1 further has a spindle 2 , rotatable around an axis of rotation 35 , in the present embodiment example consisting of a cabling spindle equipped with a protective cap 19 , in which a second feed package 15 is stored.
[0068] A so-called inner yarn 16 is extracted overhead from this second feed package 15 , and is supplied to a balloon eye or a so-called balancing system 9 arranged above the spindle 2 .
[0069] The protective cap 19 , mounted on the yarn diverting means 8 designed as a rotatable yarn plate in this embodiment example, is preferably secured against rotating by a magnetic means (not shown).
[0070] The yarn diverting means of the spindle 2 is activated by a spindle drive 3 , which can either be a direct drive or an indirect drive.
[0071] The outer yarn 5 extracted from the first feed package 7 is supplied to a controllable means 6 arranged in the yarn path between the creel 4 and the spindle 2 for influencing the yarn supply speed or the yarn tension, with which the yarn tension of the outer yarn 5 can be varied if necessary.
[0072] The means 6 is connected with a control circuit 18 via a control line, which regulates the yarn supply speed and/or the yarn tension applied to the outer yarn 5 by the means 6 .
[0073] The controllable yarn tension applied to the outer yarn 5 by the means 6 is here preferably of a magnitude that, depending on the geometry of the spindle 2 , leads to an optimisation of the free yarn balloon B, i.e. to a yarn balloon B with the smallest possible diameter.
[0074] After the means 6 the outer yarn 5 runs through the spindle drive 3 in the area of the axis of rotation of the spindle drive, and exits the hollow axis of rotation of the spindle drive 3 in a radial direction below the yarn plate 8 through a so-called yarn output bore. The outer yarn 5 then runs to the outer area of the yarn plate 8 .
[0075] With the present embodiment example the outer yarn 5 is diverted upwards at the edge of the yarn plate 8 and circles the protective cap 19 of the spindle 2 , in which the second feed package 15 is positioned, whilst forming a free yarn balloon B.
[0076] As is clear from FIG. 1 , a sensor means 33 is also arranged above the protective head 19 of the spindle 2 , which is designed as a light barrier in the embodiment example. This means that the sensor means 33 comprises a light source 41 and a light receiver 40 .
[0077] With the embodiment example shown in FIG. 1 the light barrier is positioned in such a way that a measuring beam 42 emitted by the light source 41 of the sensor means 33 , in this case a light beam, passes through the area of the yarn balloon B orthogonally to the axis of rotation 35 of the spindle 2 , and meets the associated light receiver 40 of the sensor means 33 , which is in turn connected with a control circuit 18 via a signal line.
[0078] The sensor means 33 , with which the relevant current actual diameter of the yarn balloon B to be monitored is determined, does however not have to be designed as a light barrier, but can in principle also work according to another physical principle.
[0079] The measuring beam of the sensor means 33 can for example also work with any other wavelength of the electromagnetic spectrum, for example radar, ultrasound, infrared etc.
[0080] As is clear from FIG. 1 , the outer yarn 5 extracted from the first feed package 7 and the inner yarn 16 extracted from the second feed package 15 are joined in the area of a balloon eye or a balancing system 9 , wherein the position of the balloon eye or the balancing system 9 determines the height of the free yarn balloon B that is formed.
[0081] The so-called cabling or also cording point is located in the balloon eye or the balancing system 9 , in which the two yarns, the outer yarn 5 and the inner yarn 16 , come together and for example form a cord yarn 17 .
[0082] A yarn extraction device 10 with which the cord yarn 17 is extracted and supplied to a spooling and winding device 12 via a balancing element, such as for example a compensating means 11 , is arranged above the cabling point.
[0083] The spooling and winding device 12 here comprises a drive cylinder 13 , as is usual, which drives a spool 14 by means of friction.
[0084] The means 6 for influencing the yarn supply speed and/or the yarn tension described above is either designed as an electronically regulated brake or as an active supply mechanism, wherein a combination of the two above mentioned components can also be used.
[0085] A galette, a serrated lock washer or a drive roll with a corresponding pressure roll are for example possible as design variations of a supply mechanism.
[0086] The means 6 regulates the yarn tension and/or the yarn speed of the outer yarn 5 depending on the diameter of the free yarn balloon B, which is determined by the sensor means 33 . This means that a measuring beam 42 initiated by the light source 41 of the sensor means 33 is for example crossed twice by the running outer yarn 5 forming the rotating yarn balloon B at every rotation of the yarn balloon B during the operation of the workstation 1 , which is immediately recognised as a fault in form of a shadow by the light receiver 40 of the sensor means 33 and transmitted to the control circuit 18 as an electric signal i.
[0087] The control circuit 18 then immediately calculated the current actual diameter of the yarn balloon B from the time gap between the two faults, and therefore the electric signal I generated by the light receiver 40 of the sensor means 33 at every rotation of the yarn balloon B. The control circuit 18 also immediately acts to regulate the yarn supply speed or the yarn tension of the outer yarn 5 via the means 6 if necessary when the actual detected diameter of the yarn balloon differs from the target diameter. This means that the control circuit 18 immediately initiates a correction of the diameter of the circulating yarn balloon B.
[0088] FIG. 2 shows an embodiment example for a control circuit 18 as used with the method according to the invention for maintaining a desired diameter of a yarn balloon B.
[0089] As is clear, a regulator element 20 of the control circuit 18 is connected to an input device 22 via a line 21 as well as a sensor means 33 via line 23 . The regulator element 20 is further connected with a means 6 for influencing the yarn tension via a line 24 .
[0090] Operators can enter the data of the yarn balloon created at the workstation in question via the input device 22 here, i.e. the regulator element 20 is supplied with values and data for the target diameter of a yarn balloon B via the input device.
[0091] The values and data of the target diameter of the yarn balloon B can of course be corrected at any time at the input device 22 if necessary.
[0092] The stipulated target data of the yarn balloon B are immediately compared with the actual data of the sensor means 33 in the regulator element 20 by means of the input device 22 , i.e. with data that has been generated by the sensor means 33 whilst monitoring the circulating yarn balloon B.
[0093] As already explained above the sensor means can for example be designed as a light barrier that monitors the circulating yarn forming the yarn balloon B with a light beam 42 emitted by a light source 41 .
[0094] If the regulator element 20 detects a deviation from the actual values of the yarn balloon diameter recorded by the sensor means 33 from the target values of the diameter of the yarn balloon B stipulated via the input means 22 , the regulator element 20 immediately activates the means 6 via a control line 24 , with which the yarn supply speed or the yarn tension of the outer yarn 5 can be influenced.
[0095] This means that the regulator element 20 ensures that the diameter of the monitored yarn balloon B is immediately corrected with the means 6 in a case of a deviation of actual values of the yarn balloon diameter from the target values in such a way that the target values for the diameter of the monitored yarn balloon B stipulated via the input means 22 once again exist precisely.
[0096] This means that the control circuit 18 immediately applies a correction in the control path area 25 if a fault 26 relating to the diameter of the yarn balloon B occurs in the present system, wherein regulation of the diameter of the yarn balloon B is characterized by the constant balancing of actual and target values of the yarn balloon B, i.e. such balancing is carried out at every rotation of the yarn balloon B.
[0097] This statement applies for the variable process speed of a workstation during the start and stop phases as well as during normal operation of a workstation, when a constant production speed is maintained.
[0098] The referenced balloon shape, and thus also the optimally minimised diameter of the yarn balloon B, does not only lead to a minimal energy requirement of the workstations of the yarn balloon forming textile machine, but also to a minimisation of the space requirement needed for the twisting process. This means that the space requirement needed for the twisting process, which has to date been stipulated by the yarn type or the diameter of the yarn balloons of the yarn type, amongst other things, can be clearly reduced with the method according to the invention, as there is no longer an unnecessarily large formation of the yarn balloon B thanks to the constant measuring and regulation of the diameter of the yarn balloon B irrespective of the relevant yarn type.
[0099] The continuous regulation of the diameter of the yarn balloon consequently leads to a smaller space requirement for individual workstations of a yarn balloon forming textile machine. This means that a yarn balloon forming textile machine, the workstations of which work with the method according to the invention, can be equipped with more workstations without changing the original machine length of the yarn balloon forming textile machine.
[0100] As the devices for carrying out the method according to the invention are present at every workstation, an independent yarn balloon control is possible at every workstation of the yarn balloon forming textile machine.
[0101] The values and data of the diameter of the yarn balloon of every individual workstation, or the corresponding values and data of a multitude of workstations, preferably all of the workstations of a yarn balloon forming textile machine, can also for example be evaluated in a central computer means.
[0102] The evaluated data can then serve for statistical purposes as well as for the optimisation of the referenced diameter of the yarn balloon.
[0103] Although the aim of the present method according to the invention is a twisting or cabling process that can be operated without use of a storage plate, the twisting or cabling process can also in principle be operated with an existing storage plate.
[0104] Use of the method according to the invention is in principle also possible at workstations equipped with a twisting plate. With such workstations, where the running yarn circulating during the twisting process before it circulates as a yarn balloon is subject to guiding or a constant output from a twisting plate, the method according to the invention can be used to advantage.
[0105] The method according to the invention can also be used to advantage in connection with a reference spindle. This means that the method according to the invention is used on at least one workstation of the yarn balloon forming textile machine, which works as a reference spindle. The values determined by the reference spindle by means of method according to the invention are then used for setting up the neighboring workstations of the textile machine.
[0106] It will therefore be readily understood by those persons skilled in the art that the present invention is susceptible of a broad utility and application. Many embodiments and adaptations of the present invention other than those herein described, as well as many variations, modifications and equivalent arrangements will be apparent from or reasonably suggested by the present invention and the foregoing description thereof, without departing from the substance or scope of the present invention. Accordingly, while the present invention has been described herein in detail in relation to its preferred embodiment, it is to be understood that this disclosure is only illustrative and exemplary of the present invention and is made merely for purposes of providing a full and enabling disclosure of the invention. The foregoing disclosure is not intended or to be construed to limit the present invention or otherwise to exclude any such other embodiment, adaptations, variations, modifications and equivalent arrangements, the present invention being limited only by the claims appended hereto and the equivalents thereof. | A method for operating a workstation ( 1 ) of a yarn balloon forming textile machine, wherein a yarn balloon (B) formed by a continuous yarn ( 5 ) circling a spindle ( 2 ) of the workstation ( 1 ) is scanned with a sensor means ( 33 ) at said workstation. Data (D) recorded by the sensor means ( 33 ), providing information about the current diameter of the yarn balloon (B) to be monitored, is transmitted to a control circuit ( 18 ), in that the control circuit ( 18 ) calculates the current actual diameter of the yarn balloon (B) by means of this data (D) and further known data, compares this with a stipulated target diameter of the yarn balloon (B), and in that the control circuit ( 18 ) ensures that the yarn balloon (B) has the stipulated target diameter with the aid of a means ( 6 ) switched into the yarn path of the yarn ( 5 ), for influencing the yarn tension. | 3 |
This nonprovisional application is a continuation of International Application No. PCT/EP2010/068227, which was filed on Nov. 25, 2010, and which claims priority to German Patent Application No. DE 10 2009 055 715.6, which was filed in Germany on Nov. 26, 2009, and which are both herein incorporated by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention concerns an intake manifold with an integrated charge air cooler.
2. Description of the Background Art
From the practice of motor vehicle construction, proposals are known for integrating charge air coolers into an intake manifold of an internal combustion engine, wherein the charge air cooler is cooled indirectly, which is to say with coolant flowing through it. It is customary in this context to provide the charge air cooler with a flange plate, so that it can be inserted in an opening of an intake manifold housing in the manner of a plug-in unit and the edge of the flange plate can be screwed or welded to the housing. With this type of construction, vibrations or thermally caused distortions are transmitted directly to the charge air cooler via the flange plate.
SUMMARY OF THE INVENTION
It is therefore an object of the invention to provide an intake manifold with an integrated charge air cooler, in which the charge air cooler is especially well protected from vibrations and distortions.
Because the charge air cooler is essentially fully enclosed by the housing, it can be accommodated in the housing in a sufficiently damped manner. The required feed-throughs for the coolant have a relatively small cross-sectional area and can be sealed with respect to the housing by suitable devices such that no significant forces from vibrations or thermal distortions are transmitted to the charge air cooler. In accordance with the invention, the charge air cooler is elastically supported with respect to the housing. In this way, vibrations that are first transmitted from the internal combustion engine to the housing are damped with respect to the charge air cooler, or the charge air cooler and the intake manifold housing are decoupled. In accordance with the invention, the support is accomplished by means of at least one elastic support member, which is located on a header of the charge air cooler in a detailed design that is preferred but not required. The support member may be composed of a block of an elastic material such as rubber or the like, for example, but this is not required. For example, fastening to the header can take place by means of clamping, possibly by means of a flexible tab of the header. The arrangement of the support member on the header has in particular the advantage that the support forces act on structures that are relatively insensitive mechanically.
In general, charge air within the meaning of the invention is understood to mean the gas supplied to the internal combustion engine, and in this sense also includes any desired mixtures of air and exhaust gas if exhaust gas recirculation is provided. The intake manifold in accordance with the invention can be combined with diesel engines as well as with gasoline engines.
In an embodiment of the invention, the charge air cooler has essentially the shape of a cuboid, wherein the charge air cooler can be inserted in one of the housing parts perpendicular to the largest side surface of the cuboid. This simplifies assembly of the intake manifold. In a detailed design that is preferred but not required, the charge air cooler is inserted from above.
It is advantageous in general for the charge air cooler of an intake manifold in accordance with an embodiment of the invention to be designed as a tube heat exchanger with a stack of flat tubes, wherein the coolant flows through the flat tubes and the charge air flows around them. Such construction offers high cooling performance with low weight and a small installation space. In a preferred detail design in this regard, one header is located at each end of the flat tubes, wherein the flat tubes and the headers are manufactured as a soldered block from metal, preferably aluminum. In addition to the simple and economical manufacture, there are no seals between the coolant region and the charge air region in such a construction, so that the danger of a water hammer is reduced. In another preferred detail design, at least one of the headers has a base region and a header wall that are produced together as one piece from a formed sheet metal part. This reduces both the manufacturing costs and the number of soldered joints, resulting in an especially low reject rate. For example, it is possible to make a header from only three parts, namely the formed sheet metal part and two cover parts, and in another embodiment from five parts, namely the formed sheet metal part and a total of four cover parts.
In another preferred detail design, the tube bundle includes at least two rows of tubes in a depth direction, so that multiple flow paths are available for the coolant and the heat exchanger performance can be optimized for a given installation space. In a preferred embodiment, the rows of tubes can includes separate flat tubes, and in an alternative preferred embodiment can include a one-piece flat tube with separate flow passages. Such a one-piece flat tube can be manufactured as an extruded part, for example. Furthermore, it is preferred for the coolant to flow through the rows of tubes sequentially in opposite directions, in particular in a counterflow configuration with regard to the direction of flow of the charge air. This optimizes the heat exchanger performance for a given installation space. In addition, in the case of a two-row heat exchanger with a redirection region at the end, for example, both coolant connections can be provided on the same header.
In one possible embodiment of the invention, at least one side part is arranged on the charge air cooler, wherein the side part has a structuring for producing a labyrinth seal with respect to an inside wall of the housing. By this means, a leakage flow of the charge air between the charge air cooler and the housing wall is prevented in a simple way. A labyrinth seal is effective even if the housing wall forms bulges or similar deformations as a result of temperature variations. An elastomer seal can optionally be provided in addition to the labyrinth seal.
In another embodiment, at least two support members are connected to one another via a coupling link. This makes installation easier and ensures retention of the support elements on the charge air cooler, either by itself or as an additional measure. In one preferred detail design, the coupling link has a sealing member to seal the charge air cooler with respect to the housing, so that sealing against such occurrences as leakage flows of the charge air around the charge air cooler can be accomplished at the same time.
It is advantageous in general for a header of the charge air cooler to have an overhang extending in the flow direction of the charge air beyond an inlet plane or outlet plane of a cooler network. For instance, this form can produce improved or simplified sealing against leakage flows of the charge air, for example between the header and a housing wall. In particular, it is preferred for the overhang to be provided with a sealing member and/or to form a support for a sealing member.
Depending on the requirements, the housing can be made of a plastic or a light metal, for example based on aluminum.
It is preferred for an engine flange for attachment to an intake region of a cylinder head to be provided at the outlet of the housing, wherein the engine flange preferably can be made of plastic or a light metal in accordance with requirements. For optimizing the costs, provision can be made for the engine flange to be made of light metal while the housing of the intake manifold is made of a plastic, for example. In this case the engine flange and housing are fastened together as separate parts, for example by means of threaded fittings. If the engine flange and housing are made of the same material, such as plastic or aluminum, they can be designed as a single piece of uniform material. A single-piece design with uniform material also includes the case in which, for structural reasons, the housing and engine flange are prefabricated from plastic and are then welded together as separate parts, for example by means of ultrasonic welding. Alternatively thereto, the engine flange can be molded with the housing in a single casting operation if the shape allows for this in casting.
In another embodiment, a coolant connection of the charge air cooler is elastically sealed in an airtight manner to the housing in the region of the feed-throughs. The elastic sealing reduces the transmission of distortions and vibration from the housing to the charge air cooler.
In generally advantageous manner, provision can be made for at least one coolant connection of the charge air cooler to be joined material-to-material with the charge air cooler, in a preferred detail design by means of soldering, and/or for at least one coolant connection of the charge air cooler to be joined in an interlocking manner with the charge air cooler, in a preferred detail design by means of threaded fittings and/or clips.
In an embodiment, at least one coolant connection of the charge air cooler is provided on a top side of the charge air cooler with respect to gravity. In this way, additional venting openings can be eliminated, since venting of the charge air cooler takes place automatically through its coolant connections.
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 hereinbelow 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 shows an exploded three-dimensional view of an intake manifold with an integrated charge air cooler according to the invention.
FIG. 2 shows an exploded three-dimensional view of the charge air cooler from FIG. 1 .
FIG. 3 shows a partially cut away, inverted three-dimensional view of the charge air cooler from FIG. 1 .
FIG. 4 shows a partial cross-section of the charge air cooler from FIG. 1 .
FIG. 5 shows a first variant of a housing part of the intake manifold from FIG. 1 with adjoining engine flange.
FIG. 6 shows a second variant of the housing part from FIG. 5 with adjoining engine flange.
FIG. 7 shows a three-dimensional view of a variant of the intake manifold from FIG. 1 with installed support members.
FIG. 8 shows a three-dimensional view of the charge air cooler from FIG. 3 .
FIG. 9 shows an enlarged cutaway view of the charge air cooler from FIG. 4 in the region of a header.
DETAILED DESCRIPTION
The intake manifold according to the invention shown in FIG. 1 comprises an outer housing 1 made of plastic, which comprises a bottom housing part la and a top housing part 1 b . The bottom housing part 1 a encloses the majority of the volume of the housing interior, and has an inlet 2 in the form of a tubular flange for connection to a charge air duct and an outlet 3 in the form of a rectangular opening that extends over the majority of one side wall.
The second, top housing part 1 b is designed essentially in the shape of a flat cover with rib structures 4 provided for reinforcement. Reinforcing rib structures 4 are also located over all side walls of the bottom housing part 1 a.
The installation position of the housing 1 relative to an internal combustion engine that is not shown corresponds essentially to the position in FIG. 1 . The parting plane between the housing parts 1 a , 1 b extends essentially horizontally. A charge air cooler 5 installed in the housing has essentially a cuboid shape that is essentially enclosed by the interior space of the housing 1 present between the housing parts la, 1 b . The largest side area of the cuboid extends horizontally and parallel to the parting plane between the housing parts 1 a , 1 b . As FIG. 1 shows, the charge air cooler 5 can be inserted in the bottom housing part 1 a perpendicular to the largest side area of the cuboid. Here, the orientation relative to the perpendicular relates to the installation position in the motor vehicle. It is a matter of course that the preassembly of the parts before installation in the motor vehicle can also take place in another spatial orientation. In the example according to FIG. 1 , the two housing parts 1 a , 1 b are screwed together in a sealing manner along an edge 1 c that is provided with holes. Alternatively, the parts can also be permanently welded or glued together.
In order to avoid lateral leakage flow of the charge air, sides of the charge air cooler implemented as headers 11 , 14 are embedded in convex projections 1 d of the housing part 1 a , which projections form an undercut with respect to the housing in the region of the inlet 2 . Moreover, additional sealing devices that are not shown in FIG. 1 and FIG. 2 can be provided between the headers 11 , 14 and the side walls of the housing part 1 a or convex projections 1 d ; see the variation in FIG. 3 through FIG. 5 , for example.
A first feed-through 6 for accommodating an inlet connection fitting 7 (see FIG. 2 ) for a coolant of the charge air cooler 5 is located in a bottom side of the bottom housing part 1 a . A second feed-through 8 for an outlet connection fitting 9 of the charge air cooler 5 is located in the cover-like top housing part 1 b . The connection fitting 9 is located on a top side of the charge air cooler 5 , so that no additional venting bores are provided on the charge air cooler 5 . Venting of the charge air cooler 5 with respect to the coolant flowing through it takes place without difficulty in the installed state and in operation through the upper coolant connection 9 .
The charge air cooler 5 is designed entirely as a soldered block from aluminum parts. In a known manner, at least some of the parts are solder-plated on one or both sides and are soldered in a soldering furnace after mechanical preassembly and fixturing.
In accordance with the exploded view in FIG. 2 , the charge air cooler 5 comprises a stack of, in the present case, two rows of separate flat tubes 10 , which are arranged sequentially in a depth direction T or a direction of the charge air flow. In the present case, the flat tubes extend in the horizontal plane. The coolant, for example engine coolant of a low-temperature coolant circuit, flows through the two rows R 1 , R 2 of flat tubes in opposite directions. As FIG. 2 shows, the coolant, which enters through the bottom coolant connection 7 , first flows in the row R 2 , which is to the rear in the air flow direction, is then redirected by 180° in a header 11 , and flows through the front row R 1 of flat tubes 10 in the direction opposite the rear row R 2 . With regard to the air flow, flow through the rows R 1 , R 2 takes place first through R 1 and then through R 2 , which is to say in the counterflow method.
Layers of ribs which are not shown are provided in each case between the stacked flat tubes 10 , wherein the ribs are continuous over both rows R 1 , R 2 . Located at each end of the stack of flat tubes 10 are side parts 12 that have multiple corrugation-like ribs 12 a , so that the side parts 12 can be formed from a metal sheet in a simple manner. Together with corresponding rib-shaped formations in the opposite side surfaces of the housing parts 1 a , 1 b , the ribs 12 a form a labyrinth seal; see in particular the detail representation in FIG. 4 . As a result of the multiple overlaps, good sealing of the charge air flow with respect to leakage flows between the charge air cooler 5 and housing parts 1 a , 1 b is achieved with simple means, and a leakage flow along the top and bottom side surfaces is avoided. Depending on requirements, an elastomer seal 13 can also be provided in addition, which in the representation in FIG. 4 is placed on an upward-bent, terminal edge 12 b of the side part 12 as an elongated profile.
The redirecting header 11 that is located on the end, and a header 14 on the inlet side, are made in the same construction style from a formed sheet metal part 16 and four side cover parts 15 . The formed sheet metal part 16 is provided in a center section or base part with two rows of feed-throughs 17 to accommodate the ends of the flat tubes 10 , after which lateral overhangs are folded over to form an outer header wall 18 divided into two parts. The ends of the formed sheet metal part meet in a separating region 19 between the two parts of the header wall 18 . In the case of the redirecting header 11 , openings (not shown) for the coolant to flow through are provided in this separating wall 19 . In the case of the header 14 on the inlet side, the separating wall 19 is made without openings, so that one half of the header 14 is used for the intake of the fluid and the other half of the header 14 is used for the discharge of the fluid. Overall, the charge air cooler is thus designed as a U-flow cooler with regard to the coolant flow.
The headers 11 , 14 are each completed by four cover parts 15 , which are mechanically held in tabs 20 at the edge of the sheet metal part 16 for fixturing. In a variant that is not shown, it is possible to provide only two cover parts per header 11 , 14 . On the inlet-side of header 14 , a profiled fitting 7 is placed in an opening on one of the bottom cover parts 15 , and a fitting 9 that is likewise profiled is placed on a top cover part 15 . The fittings 7 , 9 constitute coolant connections, wherein the bottom fitting 7 is used for the intake of the coolant and the top fitting 9 is used for the discharge of the coolant.
In an alternative embodiment that is not shown, the fittings 7 , 9 can also be put in place after the soldering procedure as separate parts, for example plastic parts, by means of threaded fittings, clips, adhesives or other means.
In a preferred detail design of the exemplary embodiment from FIG. 3 , the charge air cooler 5 is elastically supported on the bottom housing part 1 a by means of a spring member in the form of two spring plates 21 . The spring plates 21 are designed in the form of sheet metal strips with curved ends, wherein the curved ends each rest against one of the cover parts 15 of the headers 11 , 14 . A slight elastic mobility of the charge air cooler 5 relative to the housing 1 is provided by the spring member 21 , so that vibrations of the housing 1 are damped with respect to the charge air cooler 5 , and thermal expansions of the housing 1 and charge air cooler 5 are compensated. In useful fashion for this purpose, sufficient elastic sealing component (not shown) with respect to the feed-throughs 6 , 8 in the housing parts 1 a , 1 b are provided on the coolant connections 7 , 9 .
FIG. 5 and FIG. 6 show two embodiments, in each of which an engine flange 22 for screwing the intake manifold from FIG. 1 to the cylinder head of an internal combustion engine is provided at the bottom housing part 1 a at its outlet-side opening 3 .
In the example from FIG. 5 , the engine flange 22 , as well as the housing part 1 a, is made of plastic, with the engine flange 22 and the housing part 1 a being friction welded to one another. Consequently, they form a one-piece plastic component composed of a uniform material.
In the example from FIG. 6 , the engine flange 22 is made of aluminum, wherein it is screwed by means of threaded fittings 22 a to the housing part 1 a , which is made of plastic like the housing part in FIG. 5 . In a variation that is not shown, it is also possible for both the engine flange 22 and the housing 1 to be made of a light metal such as aluminum. Manufacture from aluminum is desirable in the case of especially high charge pressures or also in the case of high local temperatures, for example in conjunction with a high pressure exhaust gas recirculation system. Insofar as pressures and temperatures allow forming from plastic, this is frequently, but not necessarily, desirable for reasons of cost and weight. Depending on requirements, the housing parts 1 a , 1 b also may be made of different materials, such as aluminum and plastic.
In the most general sense, charge air within the meaning of the invention is understood to mean the gas supplied to the internal combustion engine, and in this sense also includes any desired mixtures of air and exhaust gas if exhaust gas recirculation is provided. The intake manifold in accordance with the invention can be combined with diesel engines as well as with gasoline engines.
In the additional exemplary embodiment shown in FIG. 7 to FIG. 9 , the charge air cooler 5 is supported with respect to the housing 1 by means of elastic support members 23 . The support members, eight in all, are molded as prismatic blocks from an elastic material such as rubber, and they each have bores or recesses 23 a on the top by means of which they are better secured to the housing 1 .
The support members 23 have the cross-section of a right triangle with a curved hypotenuse. They each rest on the side cover pieces 15 of the headers and are fastened in a clamping manner by means of a flexible tab 24 that is provided in a projecting edge of the formed sheet metal part 16 .
Each pair of support members 23 located on opposite side parts 15 of a header constitutes a structural unit together with a coupling link 25 , or is joined together by the coupling link 25 .
The coupling link 25 includes a sealing member formed as an elongated sealing lip that runs along an edge of the header and creates a seal between the housing 1 and the charge air cooler 5 , by which means leakage flows of the charge air are avoided. FIG. 8 shows one of the units composed of support members 23 and coupling link 25 during the process of installation (direction of arrow). The unit [can] be manufactured as a one-piece molded part of a single material, or can also have multiple assembled components.
Another difference from the first exemplary embodiment in FIG. 1 resides in the shape of the headers 11 , 14 . These each have an overhang 26 in the flow direction of the charge air by which they project past an inlet plane formed by the front edges of the flat tubes 10 and an outlet plane formed by the back edges of the flat tubes 10 of the cooler network of flat tubes and ribs.
In the present case, this overhang 26 serves as a support for contact of the coupling link 25 formed as a sealing lip. In alternative embodiments, a separate sealing member can also be arranged on the overhang 26 and/or the overhang forms a labyrinth seal together with a suitable form of the housing that encompasses the overhang.
It is a matter of course that the individual features of the different exemplary embodiments may be appropriately combined with one another as required.
The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are to be included within the scope of the following claims. | An intake manifold is provided that includes an integrated charge air cooler and a housing having a first housing part and a second housing part connected thereto. The charge air flows into the housing via an inlet and flows out of the housing via an outlet. The charge air cooler is disposed in the housing and is permeated by the charge air on the path from the inlet to the outlet. Also, the charge air cooler is completely enclosed by the housing, except for passages for passing a cooling fluid, and the charge air cooler is elastically supported relative to the housing by at least one elastic bearing element in particular disposed on a collector of the charge air cooler. | 5 |
This application claims priority to Korean Patent Application No. 2005-99064, filed on Oct. 20, 2005, and all the benefits accruing therefrom under 35 U.S.C. §119(a), the contents of which are herein incorporated by reference in its entirety.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to compositions comprising sulfur-containing dispersants. Specifically, the present invention relates to a sulfide phosphor paste composition comprising the sulfur-containing dispersants.
More particularly, the present invention relates to a composition comprising a sulfur-containing dispersant which has a structure containing both a carboxyl group and a thiol group as head groups or a structure containing a thiol or thiophene group as a head group, and a sulfide phosphor paste composition comprising the sulfur-containing dispersant.
2. Description of the Related Art
In recent years, various display devices have been developed and widely used as replacements for cathode ray tubes (CRTs). Such display devices include flat panel displays (FPDs), e.g., liquid crystal displays, plasma display panels, electroluminescence displays and field emission displays, and vacuum fluorescent displays. These display devices necessarily include fluorescent films and thus their luminescent properties are dependent on the physical properties of the fluorescent films.
Sulfide phosphors, such as SrGa 2 S 4 , are widely used in the fields of field emission displays and cathodoluminescent displays. Fluorescent films for a variety of display devices are produced by preparing a phosphor paste composition comprising a phosphor, uniformly applying the phosphor paste composition to a given support, and drying the coated support. Representative sulfide phosphor paste compositions are composed of a mixture of a solvent, a binder, and a sulfide phosphor, and optionally comprise a dispersant for improving the dispersibility of the phosphor.
Such sulfide phosphor pastes tend to react with moisture or be chemically unstable in organic solvents (e.g., ethyl cellulose, terpineol and butyl carbitol acetate (BCA)) used in the preparation of the pastes. Some constituent components of sulfide phosphor paste compositions may be completely dissolved in solvents, such as ethyl cellulose, thus deteriorating the luminescent properties of display devices comprising fluorescent films produced from the compositions.
Where the viscosity reduction effect of dispersants in sulfide phosphor pastes is insufficient, the phosphors are inevitably used in relatively small amounts. Conversely, since an increased loading amount of phosphors can cause an increase in the viscosity of sulfide phosphor pastes, the workability of fluorescent films prepared therefrom is poor, e.g., through formation of non-uniform fluorescent films, leading to low yields and low productivity of the fluorescent films.
BRIEF SUMMARY OF THE INVENTION
Therefore, the present invention has been made in view of the above problems of the prior art, and it is one object of the present invention to provide a sulfur-containing dispersant capable of improving the dispersibility of particulate materials, including phosphors for use in a sulfide phosphor paste composition. It is another object of the present invention to provide a sulfide phosphor paste composition having superior dispersibility and uniform physical properties.
It is another object of the present invention to provide a high-luminance fluorescent film having excellent processability.
It is yet another object of the present invention to provide a display device comprising the fluorescent film.
In accordance with one aspect of the present invention for achieving the above objects, there is provided a dispersion composition comprising a sulfur-containing dispersant which has a dual head structure containing both a carboxyl group and a thiol group, or a structure containing a thiol or thiophene group as a head group; a particulate material; and an organic solvent.
In accordance with another aspect of the present invention, there is provided a sulfide phosphor paste composition comprising the sulfur-containing dispersant, a binder solution of an organic binder in a solvent, and a phosphor.
The phosphor paste composition may comprise 40-70% by weight of the phosphor and 0.1-3% by weight of the dispersant with respect to the phosphor powder, based on the weight of sulfur-containing dispersant, phosphor, and binder solution.
In accordance with another aspect of the present invention, there is provided a fluorescent film formed from the phosphor paste composition by a known process.
In accordance with yet another aspect of the present invention, there are provided display devices, such as cathodoluminescent displays, liquid crystal displays and electroluminescence displays, which comprise the fluorescent film.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other objects, features and other advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:
FIG. 1 is a 1 H-NMR spectrum of a sulfur-containing dispersant synthesized in Preparative Example 1 of the present invention;
FIG. 2 is a graph showing changes in viscosity according to the changes in the shear rate of phosphor paste compositions prepared in Examples 1 to 3 and Comparative Example 1;
FIG. 3 is a graph showing changes in viscosity according to the changes in the shear rate of phosphor paste compositions prepared in Examples 4 to 6 and Comparative Example 2;
FIG. 4A is a graph showing the luminescent properties of fluorescent films produced from phosphor paste compositions prepared in Examples 1 and 2 and Comparative Example 1, and FIG. 4B is an enlarged partial view of the graph shown in FIG. 4 a ; and
FIG. 5A is a graph showing the luminescent properties of fluorescent films produced from phosphor paste compositions prepared in Examples 4 and 5 and Comparative Example 2, and FIG. 5B is an enlarged partial view of the graph shown in FIG. 5A .
DETAILED DESCRIPTION OF THE INVENTION
It will be understood in the following disclosure of the present invention, that when an element or layer is referred to herein as being “disposed on” another element or layer, the element or layer is in at least partial contact with another element or layer, and there are no intervening elements or layers present. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items.
It will also be understood that, although the terms first, second, third, etc., may be used herein to describe various elements, processes, components, and/or layers, these elements, processes, components, and/or layers should not be limited by these terms.
As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.
Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.
The present invention will now be described in more detail.
A sulfur-containing dispersant as disclosed herein has a dual head structure containing both a carboxyl group and a thiol group or a structure containing a thiol or thiophene group as a head group.
Specifically, the sulfur-containing dispersant comprises:
a compound of Formula 1
wherein
X is substituted C 1-200 alkyl, unsubstituted C 1-200 alkyl, substituted aryl, unsubstituted aryl, substituted arylalkyl, or unsubstituted arylalkyl,
R is H or methyl, and P is a number from 1 to 10;
a compound of Formula 2
wherein 1 is a number from 1 to 20;
a compound of Formula 3
CH 3 (CH 2 ) 10 CH 2 —SH (3);
a compound of Formula 4
or a combination comprising at least one of the foregoing compounds.
The sulfur-containing dispersant serves to improve the dispersibility of a sulfide phosphor paste composition and permits an increase in the amount of the phosphor used while maintaining the viscosity of the phosphor paste composition at a constant level. Accordingly, a phosphor paste composition comprising the sulfur-containing dispersant can be used to produce a fluorescent film or a display device having improved luminance.
More specifically, the dispersant of Formula 1 can be represented by Formula 5 below:
wherein A is H or C 1-12 alkyl, m and n are each independently a number from 1 to 20, and R is as defined in Formula 1.
In an exemplary embodiment, a dispersant of Formula 5 can be synthesized by Reaction Scheme 1 below.
wherein BMA represents butyl methacrylate, TMSMA represents trimethylsilyl methacrylate, and m and n are as defined in Formula 5.
The sulfur-containing dispersant is useful in dispersion compositions including sulfide phosphor paste compositions, but is not limited thereto. The sulfur-containing dispersant can be added to any dispersion in which particulate materials, including nanomaterials such as inorganic nanoparticles, are dispersed in organic solvents. As used herein, the term “nanomaterials” refers to particulate materials having an average largest dimension of less than 1,000 nanometers (nm), specifically less than or equal to 500 nm, and more specifically less than or equal to 100 nm.
The present invention provides a phosphor paste composition comprising a binder solution and a phosphor, in addition to the sulfur-containing dispersant. The components other than the sulfur-containing dispersant may be identical or similar to those used in conventional phosphor paste compositions.
The binder solution includes a solvent and an organic binder. The organic binder functions to impart the viscosity of the phosphor paste composition after being dissolved in the solvent and to impart a binding force to the components after the phosphor paste composition is dried. Examples of organic binder resins that can be used in the present invention include, but are not limited to, acrylic polymers, styrenic polymers, cellulose polymers, methacrylic ester polymers, styrene-acrylic ester copolymers, and polycarbonate polymers. Exemplary binders include polystyrene, polyvinylbutyral, polyvinyl alcohol, polyethylene oxide, polypropylene carbonate, polymethylmethacrylate, and ethyl cellulose. Combinations comprising at least one of the foregoing organic binders may also be used. In an embodiment, cellulose polymers, such as for example ethyl cellulose, are preferred upon screen printing.
Taking into consideration the kinds of the phosphor and the organic binder and the desired physical properties of the phosphor paste composition, the solvent used to prepare the binder solution can be selected from commercially available solvents and solvent mixtures. There is no particular restriction as to the kind of solvents that can be used in the phosphor paste composition of the present invention, but it is preferred to use solvents that are volatilized at 150° C. or higher.
Exemplary solvents include aromatic hydrocarbon compounds, e.g., toluene and xylene, ether compounds, e.g., tetrahydrofuran and 1,2-butoxyethane, ketone compounds, e.g., acetone and methyl ethyl ketone, ester compounds, e.g., ethyl acetate, butyl acetate and butyl carbitol acetate (BCA), alcohol compounds, e.g., isopropyl alcohol, diethylene glycol monobutyl ether, terpineol and 2-phenoxyethanol, and the like. A preferred mixed solvent consists of terpineol and butyl carbitol acetate in a mixing ratio of 1:1 (w/w) to 1:2.5 (w/w) and preferably 1:1.7 (w/w).
The binder solution includes 1.5-5% by weight of the organic binder and the remainder of solvent, based on the combined weights of organic binder and solvent. When the organic binder is used in an amount of less than 1.5% by weight, the amount of the solvent used is relatively large compared to that of the organic binder, leading to a deterioration in the coating quality of a fluorescent film. Meanwhile, when the organic binder is used in an amount exceeding 5% by weight, the content of the solvent is lower relative to the organic binder, thus reducing the amount of the phosphor used in the phosphor paste composition.
The phosphor used in the phosphor paste composition is not specially restricted so long as it is used to prepare conventional phosphor paste compositions. There is no restriction as to the kind and composition of the phosphor used in the present invention. Since the phosphor paste composition is mainly used to form fluorescent films for display devices, such as cathodoluminescent displays, liquid crystal displays and electroluminescence displays, the kind and composition of the phosphor may be suitably selected according to the kind of excitation sources used in the display devices to excite the fluorescent films formed from the phosphor paste composition.
Specifically, as suitable phosphors, there can be used commercially available red, green and blue phosphors in the form of oxide solid solutions that are currently used in display devices. A preferred phosphor is a mixture of oxides of barium, magnesium and aluminum in the form of a solid solution. Particularly, the dispersant can be added to a paste composition comprising a sulfide phosphor, such as SrGa 2 S 4 or La 2 O 2 S, to further improve the dispersibility of the composition.
More specifically, examples of sulfide phosphors that can be used in the present invention include, but are not limited to, SrS:Eu 2+ , SrGaS:Eu 2+ , SrGa 2 S 4 , SrCaS:Eu 2+ , ZnS:Ag + , CaS:Eu 2+ , ZnS:Cu + Al 3+ , ZnS:Ag + , Cl − , La 2 O 2 S, La 2 O 2 S:Eu 3+ , Y 2 O 2 S:Eu 3+ , CaAl 2 S 4 , and BaAl 2 S 4 :Eu 2
The phosphor paste composition may further comprise at least one additive selected from plasticizers, leveling agents, lubricants, antifoamers and the like so long as the physical properties of the composition are not significantly adversely affected.
The phosphor paste composition may comprise 40-70% by weight of the phosphor and 0.1-3% by weight of the dispersant with respect to the phosphor powder, based on the weight of sulfur-containing dispersant, phosphor, and binder solution. When the content of the dispersant is less than 0.1% by weight, the amount of the phosphor used is relatively increased and thus the viscosity of the phosphor paste composition is not maintained at a constant level. Also, when the content of the dispersant exceeds 3% by weight, the contents of the other components such as the phosphor and organic binder decrease relative to the dispersant, and the physical properties of the phosphor paste composition may be adversely affected.
Typically, the amount of phosphor dispersed in a similar phosphor paste composition but using non-sulfur-containing dispersants can be less than 40% by weight based on the weight of phosphor, dispersant, and binder solution. However, use of the sulfur-containing dispersants disclosed herein can allow an increase in the phosphor content of the phosphor paste composition to 40-70% by weight, based on the weight of phosphor, dispersant, and binder solution. The increased phosphor content in the phosphor paste composition can improve the luminance of a fluorescent film formed from the phosphor paste composition.
The phosphor paste composition can be prepared by adding the dispersant to the binder solution and adding the phosphor powder thereto. Specifically, the phosphor paste composition can be prepared in accordance with the following procedure. First, an organic binder, such as ethyl cellulose, is dissolved in a mixed solvent of butyl carbitol acetate and α-terpineol. Then, to the solution are added the sulfur-containing dispersant and an additive, such as an antifoamer or a lubricant, followed by the addition of a phosphor. The resulting mixture is homogeneously dispersed using a mill, such as a 3-roll mill, to prepare the final phosphor paste composition.
In another aspect, the present invention is directed to a fluorescent film produced from the phosphor paste composition. The fluorescent film is produced by applying the phosphor paste composition to a support, such as glass or transparent plastic, to form a particular pattern thereon and heating the coated support by drying and baking to remove volatiles (e.g., solvent) and harden the phosphor paste. The phosphor paste composition desirably forms a uniform, low defectivity layer on the support. Thus, in an embodiment, a fluorescent film comprises a phosphor layer comprising the phosphor, the organic binder, and the sulfur-containing dispersant, and the support, wherein the phosphor layer is disposed on and in at least partial contact with the support.
The fluorescent film can be produced and patterned using known techniques, including but not limited to pattern screen printing, electrophoresis, photolithography, ink jet, and the like.
Since the fluorescent film produced from the phosphor paste composition comprising the sulfur-containing dispersant enables the use of a larger amount of the phosphor in proportion to the amounts of organic binder and sulfur-containing dispersant, the luminance is thereby improved, whereas any increase in viscosity is relatively limited and does not significantly adversely affect the coating properties and/or uniformity of the phosphor paste composition and any fluorescent film prepared therefrom. Thus, the processability of the fluorescent film is improved.
The fluorescent film can be used for the fabrication of a variety of display devices, including cathodoluminescent displays, liquid crystal displays, electroluminescence displays, field emission displays and vacuum fluorescent displays. Display devices comprising the fluorescent film exhibit improved luminescent properties and uniform physical properties.
The present invention will be explained in more detail with reference to the following examples illustrating preferred embodiments of the present invention. These examples are given for the purpose of illustration and are not to be construed as limiting the scope of the invention.
PREPARATIVE EXAMPLE 1
Preparation of Sulfur-Containing Dispersant of the Formula (6)
Methyl trimethylsilyl dimethylketene acetal (3.48 g, 20 mmol, Aldrich) as an initiator, tetrabutylammonium-3-chlorobenzoate (0.8 g, 0.2 mmol) as a catalyst, and purified acetonitrile (0.5 ml) were placed in a 50 ml round-bottom flask, and stirred using a magnetic bar for one hour. To the reaction solution was slowly added a solution of butyl methacrylate (BMA, 8.18 g, 57.5 mmol, Aldrich) and trimethylsilyl methacrylate (TMSMA, Aldrich) in purified THF (3 ml). The resulting mixture was stirred for 2 hours. After the disappearance of the butyl methacrylate and trimethylsilyl methacrylate was confirmed by gas chromatography (GC), a solution (0.5 ml) of tetrabutylammonium-3-chlorobenzoate (0.8 g, 0.2 mmol) in acetonitrile was added thereto. To the reaction solution was added a solution of 2-(methylthio)ethyl methacrylate (1.6 g, 10 mmol) in purified THF (2 ml). After the resulting mixture was stirred for 2 hours, the solvents were removed using a rotary evaporator. The obtained residue was dissolved in methanol and refluxed at 70° C. for 3 hours. The methanol was removed from the reaction solution using a rotary evaporator. The obtained residue was dissolved in methylene chloride, washed with distilled water, and filtered. After the methylene chloride was removed from the filtrate using a rotary evaporator, the obtained residue was dried in a vacuum oven for 12 hours, yielding a dispersant (9.2 g) as a viscous oil. The structure of the dispersant (6) was identified by 1 H-NMR spectroscopy ( FIG. 1 ).
EXAMPLE 1
A commercially available SrGa 2 S 4 powder (KX501A Kasei Optonix Ltd., Japan) was used as a phosphor. The phosphor powder was dried in a vacuum at 130° C. for 24 hours before use Separately, 0.51 g of ethyl cellulose as an organic binder was dissolved in a mixed solvent of α-terpineol (4.61 g) and butyl carbitol acetate (7.68 g) to prepare a binder solution. The phosphor powder was added to the binder solution, and then the sulfur-containing dispersant prepared in Preparative Example 1 was added thereto. The resulting mixture was milled to prepare a phosphor paste composition of the present invention.
EXAMPLES 2 AND 3
Phosphor paste compositions were prepared in the same manner as in Example 1, except that 1-dodecanethiol (1-dodecanethiol, Aldrich, USA) (Example 2) of Formula 3 and 3-dodecylthiophene (1-dodecanethiol, Aldrich, USA) (Example 3) of Formula 4 were used as dispersants.
COMPARATIVE EXAMPLE 1
A phosphor paste composition was prepared in the same manner as in Example 1, except that no dispersant was used.
EXAMPLES 4 TO 6
Phosphor paste compositions were prepared in the same manner as in Examples 1 to 3, respectively, except that a La 2 O 2 S powder (KX-681, Kasei, Japan) was used as a phosphor.
COMPARATIVE EXAMPLE 2
A phosphor paste composition was prepared in the same manner as in Comparative Example 1, except that a La 2 O 2 S powder (KX-681, Kasei, Japan) was used as a phosphor.
EXPERIMENTAL EXAMPLE 1
Evaluation of Changes in Viscosity of Phosphor Paste Compositions
Changes in viscosity with increasing shear rates of the phosphor paste compositions prepared in Examples 1 to 3 and Comparative Example 1 were measured, and the obtained results are shown in FIG. 2 . The viscosity was measured using a viscometer (AR2000, Thermal Analysis, USA). The measurement was done using a #14 spindle at 24.5-25.5° C. for 30 seconds. For comparison, changes in the viscosity of the phosphor paste prepared in Comparative Example 1 were measured according to changes in shear rate, and the results are shown in FIG. 2 .
The graph shown in FIG. 2 demonstrates that the phosphor paste composition of Example 1 using the sulfur-containing dispersant exhibits distinct viscosity reduction effect when compared to the phosphor paste composition prepared in Comparative Example 1.
These results suggest that the phosphor paste compositions comprising the dispersants permit the use of a larger amount of the phosphor, thus improving the luminescent properties of fluorescent films produced from the compositions.
EXPERIMENTAL EXAMPLE 2
Evaluation of Changes in Viscosity of Phosphor Paste Compositions
Changes in viscosity with increasing shear rates of the phosphor paste compositions prepared in Examples 4 to 6 and Comparative Example 2 were measured by the same procedure as described in Experimental Example 1. The results are shown in FIG. 3 . The graph shown in FIG. 3 demonstrates that the phosphor paste composition of Example 5 using the sulfur-containing dispersant exhibits distinct viscosity reduction effect when compared to the phosphor paste composition prepared in Comparative Example 2.
These results suggest that the phosphor paste compositions comprising the sulfur-containing dispersants permit the use of a larger amount of the phosphor, thus improving the luminescent properties of fluorescent films produced from the compositions.
EXPERIMENTAL EXAMPLE 3
Evaluation of Luminescent Properties of Phosphor Paste Compositions
Each of the phosphor paste compositions prepared in Examples 1 and 2 and Comparative Example 1 was coated using a film applicator (BYK-Gardner®) to a thickness of 30 μm on a glass support. The coating layer was fired to 480° C. at a rate of 5° C./min. using a lamp to form a fluorescent film. The luminescent properties of the fluorescent film were evaluated.
The evaluation of the luminescent properties was conducted using a Phosphor of Emission and Decay Measurement System (an assembly of a VUV excimer lamp (USHIO, Japan) and a vacuum chamber system (Motech vacuum, Korea)) under the following conditions:
Vacuum pressure: 3-10 torr
Light source wavelength: 146 nm
Wavelength range: 230-780 nm
Wavelength interval: 1 nm.
The results are shown in FIG. 4 a . FIG. 4 b is an enlarged partial view of the graph shown in FIG. 4 a . For comparison, the luminescent properties of the phosphor powder used in Example 1 were measured and the obtained results are shown in the figures.
As shown in FIGS. 4 a and 4 b , the maximum luminescence intensity of the compositions (Examples 1 and 2) prepared using the sulfur-containing dispersants is increased by 3.4% and 2.1%, respectively, compared to that of the phosphor powder. In contrast, the maximum luminescence intensity of the composition (Comparative Example 1) using no dispersant is decreased by 4.0%, compared to that of the phosphor powder. These results show that the phosphor paste compositions comprising the dispersants exhibit improved luminescence intensity as compared to conventional phosphor paste compositions.
EXPERIMENTAL EXAMPLE 4
Evaluation of Luminescent Properties of Phosphor Paste Compositions
The luminescent properties of the phosphor paste compositions prepared in Examples 4 and 5 and Comparative Example 2 were evaluated by the same procedure as described in Experimental Example 3.
The results are shown in FIG. 5 a . FIG. 5 b is an enlarged partial view of the graph shown in FIG. 5 a.
As shown in FIGS. 5 a and 5 b , the maximum luminescence intensity of the fluorescent films produced from the compositions (Examples 4 and 5) using the sulfur-containing dispersants is increased by 3.0% and 3.6%, respectively, compared to that of the phosphor powder. In contrast, the maximum luminescence intensity of the fluorescent film produced from the composition (Comparative Example 2) using no dispersant is decreased by 2.8%, compared to that of the phosphor powder. These results show that the phosphor paste compositions comprising the dispersants improve the luminescence intensity of fluorescent films as compared to conventional phosphor paste compositions.
Although the preferred embodiments have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications and variations are possible, without departing from the scope and spirit of the invention as disclosed in the appended claims. Accordingly, such modifications and variations are intended to come within the scope of the appended claims.
As apparent from the above description, the novel sulfur-containing dispersant has advantages that it improves the dispersibility of a phosphor paste composition and solves the problem of oxidation arising from the use of organic solvents. Particularly, the sulfur-containing dispersant exhibits superior effects when it is used to prepare a sulfide phosphor paste composition.
Since the phosphor paste composition comprising the sulfur-containing dispersant has improved dispersibility and constant viscosity, it permits the use of a larger amount of a phosphor, thus enabling the formation of uniform fluorescent films having improved luminescent properties. Therefore, according to the present invention, display devices, such as LCDs, having high luminance and excellent processability can be fabricated. | A sulfide phosphor paste composition comprising a sulfur-containing dispersant, and a fluorescent film prepared therefrom, are provided. The sulfur-containing dispersant has a dual head structure containing both a carboxyl group and a thiol group or a structure containing a thiol or thiophene group as a head group. An oligomeric sulfur-containing dispersant is also provided. Adsorption of the dispersant on the surface of the sulfide phosphor prevents aggregation of the phosphor particles, and thereby improves the dispersibility of the sulfide phosphor paste composition, the homogeneity of the phosphor in the paste composition, and the density of a film produced from the paste composition. Fluorescent films and display devices produced from the phosphor paste composition exhibit improved luminescent properties and excellent processability. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a process for preparing a carbon product by using a coal type acicular coke. More particularly, it relates to a process for preparing a carbon product having excellent thermal shock resistance.
2. Description of the Prior Arts
Acicular cokes used for various carbon products have been produced by using petroleum type sources. Recently, various processes for producing acicular cokes by using coal type oils have been proposed.
The carbon products have been used as graphite electrodes, carbon brushes, carbon products of machines, electrode plates and substrates for chemical plants in various industrial fields. Recently, high quality of the carbon products has been required and various characteristics such as electrical, mechanical and thermal charactertistics of the carbon products have been improved to obtain high quality carbon products because of developments and rationalizations of technology.
For example, in a preparation of artificial graphite electrodes for steel productions, certain ultra-high power operation has been employed because of the rationalization by steel makers. As a result, it has been required to use a graphite electrode having excellent thermal shock resistance in high quality. That is, a graphite electrode having excellent characteristics such as great strength and low thermal expansion coefficient, low electric specific resistance and low modulus of elasticity has been required. Various conditions for the preparation of carbon products have been studied to provide satisfactory characteristics. It has been proposed to attain various improvements in steps of preparations of carbon products such as a condition for selecting particle sizes of cokes in blending and a selection of a kind and content of a binder, and a kneading operation, a molding operation, a baking operation, an immersing operation and a graphitizating operation. An improvement of a coke itself for the carbon product has been also studied.
Thus, it has been known that the carbon products prepared by using a coal type acicular coke, have characteristics such as low thermal expansion coefficient and excellent graphitizability, however there has not been found any technology for obtaining a carbon product having satisfactory characteristics for high thermal shock resistance especially high strength.
The inventors have studied, in detail, functions of characteristics of cokes for imparting characteristics of carbon products in order to prepare carbon products having excellent thermal shock resistance by using coal type acicular cokes. As a result, the inventors have found that qualities of carbon products especially thermal shock resistance closely relate to pore volume of the coal type acicular cokes.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a process for preparing a carbon product having excellent thermal shock resistance by using a coal type acicular coke.
The foregoing and other objects of the present invention have been attained by providing a process for preparing a carbon product which comprises: (a) mixing a hydrocarbon material derived from coal with a hydrocarbon solvent having a boling point or a distillation temperature for 95 vol % of the solvent less than 350° C. and a B.M.C.I. value of 5 of 70, said value being defined as: B.M.C.I.=48,640/k+473.7S-456.8, wherein k is the average boiling point (°K.) and S is the specific gravity at 60° F., (b) separating insoluble material which settles from the resulting mixture upon standing, (c) removing by distillation at least a portion of said solvent from the insoluble matter free mixture, (d) coking the residue obtained after distillation, thereby forming an acicular, green coke, (e) calcining the acicular green coke, thereby obtaining an acicular calcined coke having a pore volume of more than 40×10 -3 cc/g; and (f) blending the acicular calcined coke with a binder, shaping the blend and graphitizing the blend at a high temperature. The pore volume is preferably in a range of 60 to 200 m cc./g.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The coal type acicular coke can be obtained by coking a coal type source such as coal tar and coal tar pitch if necessary, after a modification such as a separation o quinolin-insoluble matters (hereinafter referring to as Q.I.) from the coal type source and then calcining it.
The preparation of the coal type acicular coke will be illustrated in detail.
The sources are hydrocarbons containing Q.I. and condensed ring aromatic compounds. More particularly, the coal type sources can be coal tar and soft coal tar pitch.
The coal type source is admixed with hydrocarbons having a boiling point or a distillation temperature for 95 vol % of the solvent less than 350° C. and a B.M.C.I. value of 5 to 70, said value being defined as
B.M.C.I.=48,640/k.+473.7S-456.8
wherein k represents an average boiling point (°K.), and S represents a specific gravity at 60° F., which can be cyclohexane, kerosene and mixtures of kerosene and naphthalene oil at a ratio of 1:0.3 to 1:1 by weight.
The mixture of the coal type source and the solvent is kept in settling to precipitate the insoluble matters and the insoluble matters are separated by a simple operation such as a decantation to obtain hydrocarbons which do not substantially contain Q.I. A content of Q.I. in the hydrocarbons including condensed aromatic compounds obtained as a supernatant is decreased to less than 0.8% by weight preferably less than 0.3% by weight especially less than 0.1% by weight, based on the modified coal type source as described below.
The operations in the mixing step, the sedimentation step and the separation step are preferably carried out at a temperature of about 60° to 350° C. for the easy operations. For example, it is preferable to carry out at about 60° to 90° C. in the case of coal tar source and at about 150° to 290° C. in the case of soft coal tar pitch source.
The resulting supernatant is distilled at a distillation temperature of lower than a boiling point of the solvent or a distillation temperature for 95 vol. % or lower than about 350° C. The distillate is recovered and can be reused as the solvent if desired. For example, when coal tar is used as the source, it is preferable, for a coking, to form a pitch by heating to about 300° C. after the distillation of the solvent (such as a boiling point of 81° C. in the case of cyclohexane). After the distillation, the residue is discharged as the modified source.
The resulting modified source is used as a stock oil for coking. The acicular green coke is obtained by coking it by a delayed coking process. The main operations for the delayed coking process is as follows.
A recycle ratio as a ratio of a recycle oil fed from a fine distillation tower to a newly fed stock oil for coking is in a range of about 0 to 2. The mixture fed into the coking drum is heated at about 440° to 520° C. as the temperature at the outlet of the furnace. The coking drum is operated so as to maintain the temperature for about 24 to 48 hours. The top of the coking drum is kept at about 400° to 500° C. under a pressure of about 1.5 to 10 atm. An oil and a vapor are recycled from the coking drum to a fine distillation tower. Thus, the acicular green coke containing about 5 to 13% of volatile matters is obtained and is calcined at about 1000° to 1600° C. to obtain the acicular coke.
The resulting acicular coke is pulverized, seived and blended so as to produce the carbon product having high quality.
The most important operation of the present invention is to select the acicular coke which has the specific pore volume per 1 g. of the acicular coke measured by a mercury compressing process. A sample for the measurement is prepared by seiving it to be 10 to 20 mesh (Japanese Industrial Standard) and it is measured as follows. The pore volume per 1 g. of coke is measured by a mercury porosimetry process. Mercury is compressed into pores of the coke as the sample after evacuating under a reduced pressure of lower than 0.03 mmHg. and a volume of mercury impregnated from the reduced pressure of 0.1 kg./cm 2 to the pressure of 1000 kg./cm 2 is measured to calculate the pore volume.
Radius of pores measured by the equation of
γ=75000/p
wherein γ represents a radius of pores (A) and p represents a pressure (kg./cm 2 ), in the 480 dyne/cm of a surface tension of mercury and 140° of a contact angle, is usually in a range of 7.5×10 1 to 7.5×10 5 A.
In order to obtain the acicular coke having a pore volume of more than 40×10 -3 cc./g., various conditions such as a selection of the hydrocarbon source, an amount of the removed Q.I., a condition for coking and a temperature and a time for calcination, can be selected. In usual, the acicular coke having a pore volume of more than 40×10 -3 cc./g. for the present invention can be obtained by selecting the above-mentioned conditions.
In the relation of the pore volume and the quality of the carbon product, the carbon product having excellent thermal shock resistance can be obtained by using the acicular coke having a pore volume of more than 40×10 -3 cc./g. preferably more than 60×10 -3 cc./g. especially more than 80×10 -3 cc./g. The porosity is preferably less than 200×10 -3 cc./g. especially less than 150×10 -3 cc./g. When the acicular coke having a large pore volume such as more than 200×10 -3 cc./g. is used, the strength of the carbon product is disadvantageously low.
A preparation of an artificial graphite electrode as a typical process for preparing a carbon product by using the acicular coke having the specific pore volume will be illustrated in detail.
The acicular coke as an aggregate is pulverized and seived to separate it into grains having a maximum diameter of about 10 mm and powders having sizes of 200 mesh or less. The grain and the powder are blended at a ratio of about 60:40 to 40:60 to control the particle sizes. The coke having suitable particle sizes is blended to a binder such as a coal tar pitch at a ratio of about 70 to 76% of the coke to about 24 to 30% of the binder and the mixture was kneaded at about 140° to 160° C. The resulting kneaded mixture was cooled and molded by an extrusion molding at about 80° to 120° C. to obtain a molded product. The molded product is baked at a maximum temperature of about 750° to 1000° C. to obtain a baked product.
If it is necessary to improve characteristics of the baked product, a pitch is impregnated into the baked product at about 250° C. under a reduced pressure and the impregnated product is baked again as a second baking. The operations for the impregnation and the baking can be repeated if necessary.
The resulting baked product is graphitized in an electric furnace etc. at about 2600° to 3000° C. under feeding an electric current for about 2 to 4 days and annealing for longer than 10 days to obtain the object graphite electrode.
In accordance with the process of the present invention, the carbon product having excellent thermal shock resistance can be obtained by the simple process without any special complicated operation. This is especially advantageous.
In accordance with the present invention, the coal type source is coked and calcined to obtain the coal type acicular coke having a specific pore volume and the coke is used as the aggregate to obtain the carbon product having high strength and low thermal expansion coefficient and excellent thermal shock resistance as the baked, graphitized carbon product such as the artificial graphite electrode having high quality and high strength.
The present invention will be further illustrated by certain examples which are provided for purposes of illustration only.
EXAMPLE 1
A soft coal tar pitch having 6.8% by weight of a content of Q.I. was admixed with hydrocarbons as mixture of kerosene and naphthalene oil having about 250° C. of a distillation temperature for 95 vol. % and about 40 of B.M.C.I. value as the solvent. The mixture was heated and mixed and kept in stand-steel for sedimentation and a supernatant was separated and distilled to remove the solvent. A modified source having less than 0.1% by weight of a content of Q.I. was obtained. The operations were carried out by a batch system. The modified source was heated from the ambient temperature and maintained at about 480° C. under a pressure of about 2.5 kg./cm 2 for about 22 hours whereby it was coked to obtain an acicular green coke. The acicular green coke was charged into a crucible with a cap and heated at about 1300° C. for about 2 hours under flowing nitrogen gas to calcine it. The acicular coke was obtained. The acicular coke was pulverized, seived and reduced to separate it into various mesh particles. The coke having a particle size of 10 to 20 mesh (Japanese Industrial Standard) was sampled and a pore volume of the sample was measured by a cathetometer and a mercury compressing type porosimeter. As a result, the pore volume for pores having radius of from 7.5×10 1 to 7.5×10 5 A was 49×10 -3 cc./g.
The cokes having different particle sizes were blended to give the distribution of the particle sizes as follows. 5 wt. % of 4 to 6 mesh; 20 wt. % of 6 to 10 mesh; 15 wt. % of 10 to 20 mesh; 10 wt. % of 20 to 36 mesh; 16 wt. % of 100 to 200 mesh; 16 wt. % of 200 to 325 mesh and 18 wt. % of less than 325 mesh.
Hundred wt. parts of the blended coke were admixed with 33 wt. parts of coal tar pitch (softening point of about 80° C.) as the binder and kneaded at about 145° C. for about 1 hour to obtain a mixture of coke and the binder. The mixture was cooled to about 115° C. and extruded for an extrusion molding at 115° C. at a nozzle ratio of 1/3.75 to obtain rodes of the extruded products which had a diameter of about 2 cm and a length of about 12 cm.
The extruded products were charged with a packing powder in an electric furnace and baked by heating the furnace to about 1000° C. during about 72 hours, to obtain baked products. Then, the baked products were charged with the packing powder in a graphite crucible and graphitized in an industrial graphitization furnace by heating it to about 3000° C. to obtain graphite products.
In accordance with Japanese Industrial Standard R 7202, characteristics of the resulting graphite products (two samples) were measured. The mean values are shown in Table 1 in the column of Example 1.
EXAMPLE 2
In accordance with the process of Example 1 except using a soft coal tar pitch having 2.7% by weight of a content of Q.I. and operating in a continuous system, a modified source having less than 0.1% by weight of a content of Q.I. was produced.
The modified source was coked by a delayed coking process for about 24 hours under conditions of a temperature at an outlet of a furnace of 500° to 515° C.; a recycle ratio of about 0.3; and a pressure at a top of a coking drum of about 3.5 kg./cm 2 G. to obtain an acicular green coke.
In accordance with the process of Example 1, the acicular green coke was calcined to obtain an acicular calcined coke and a pore volume of the acicular calcined coke was measured. The pore volume was 60×10 -3 cc./g/ coke.
In accordance with the process of Example 1 except admixing the acicular coke with 32 wt. parts of coal tar pitch as the binder and extruding the mixture at a nozzle ratio of 1/3 in an extrusion molding to obtain an extruded product having a diameter of about 2.5 cm and graphitizing the extruded product after baking at about 3000° C. for about 30 minutes in Tamman electric furnace, a graphite product was prepared. The characteristics of the baked product and the graphite product are shown in Table 2 in the column of Example 2.
EXAMPLE 3
In accordance with the process of Example 1 except charging the acicular green coke obtained in Example 2 in a crucible without a cap, it was calcined to obtain an acicular coke and a pore volume was measured. As a result, the pore volume was 85×10 -3 cc./g. coke.
In accordance with the process of Example 2 except using the resulting acicular coke and 34 wt. parts of coal tar pitch as the binder, a graphite product was prepared. The characteristics of the products are shown in Table 2 in the column of Example 3.
EXAMPLE 4
In accordance with the process of Example 1 except adding kerosene having about 250° C. of a distillation temperature for 95 vol. % and about 19 of B.M.C.I. value as the solvent to the soft coal tar pitch and operating in a continuous system, a modified source having less than 0.1% by weight of a content of Q.I. was produced.
The modified source was coked by a delayed coking process for about 24 hours under conditions of a temperature at an outlet of a furnace of 485° to 505° C.; a recycle ratio of about 0.7 to 1.1; and a pressure at a top of a coking drum of about 3.5 kg./cm 2 G. to obtain an acicular green coke.
In accordance with the process of Example 1, the acicular green coke was calcined at 1400° to 1460° C. in an industrial rotary kiln to obtain an acicular calcined coke and a pore volume of the acicular calcined coke was measured. The pore volume was 93×10 -3 cc./g. coke.
In accordance with the process of Example 2 except admixing the acicular coke with 35 wt. parts of coal tar pitch as the binder a graphite product prepared. The characteristics of the baked product and the graphite product are shown in Table 2 in the column of Example 4.
TABLE 1______________________________________Pore volume of coke Example 1(× 10.sup.-3 cc./g.) 49______________________________________Characteristics of graphiteproductBending strength (kg/cm.sup. 2) 78Thermal expansioncoefficient (× 10.sup.-7 /°C.) 7.0Electric specific resistance(× 10.sup.-4, Ω-cm) 7.32Modulus of elasticity(kg/mm.sup.2) 706______________________________________
TABLE 2______________________________________Pore volume of Exp. 2 Exp. 3 Exp. 4coke (× 10.sup.-3 cc./g.) 60 85 93Kind of product B.P. G.P. B.P. G.P. B.P. G.P.______________________________________Characteristics ofproductBending strength(kg./cm.sup.2) 125 92 130 107 -- 100Thermal expansioncoefficient(× 10.sup.-7 /°C.) 13.4 6.9 13.1 6.6 -- 7.2Electric specificresistance(× 10.sup.-4, Ω-cm) 55.6 9.74 54.4 9.42 44.9 11.1Modulus of elasticity(kg./mm.sup.2) 1115 616 1204 658 1149 691______________________________________ Note: B.P.: Baked Product G.P.: Graphite product | A process for preparing a carbon product, which comprises: (a) mixing hydrocarbon material derived from coal with a hydrocarbon solvent having a boiling point or a distillation temperature for 95 vol % of the solvent less than 350° C. and a B.M.C.I. value of 5 to 70, the value being defined as: B.M.C.I.=48,640/k+473.7S-456.8, wherein k is the average boiling point (°K) and S is the specific gravity at 60° F., (b) separating insoluble material which settles from the resulting mixture upon standing, (c) removing by distillation at least a portion of said solvent from the insoluble matter free mixture, (d) coking the residue obtained after distillation, thereby forming an acicular, green coke, (e) calcining the acicular green coke, thereby obtaining an acicular calcined coke having a pore volume of more than 40+10 -3 cc/g, and (f) blending the acicular calcined coke with a binder, shaping the blend and graphitizing the blend at a high temperature. | 2 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims priority to German Patent Application No. 102010054685.2, filed Dec. 16, 2010, which is incorporated herein by reference in its entirety.
TECHNICAL AREA
[0002] The technical field relates to a rear floor module arranged between two frame rails of a vehicle body running essentially in the longitudinal direction of the vehicle.
BACKGROUND
[0003] Frame rails of a motor vehicle body are typically connected with each other by one or more cross members in the rear of the body, to form a closed rear or back frame. The position of the cross member varies when viewed in the longitudinal direction of the vehicle, and adjusted to the respective motor vehicle configuration or the motor vehicle type. For example, depending on whether the motor vehicle is to be equipped with a trailer/towing device or an extendible load carrier, this may require that corresponding changes be made to the design of the vehicle body, in particular with respect to the position of the cross member. This holds true in equal measure for different vehicle types, for example for sedans or caravans or station wagons or limousines.
[0004] In addition, new drive concepts for vehicles, in particular for hybrids or fuel-cell powered vehicles, require a modified or variably adjustable partitioning of the installation space for accommodating energy storage modules or fuel containers. In particular for hybrids or purely electric-powered vehicles, it is desirable to incorporate the batteries they require as deeply as possible in the vehicle, to improve the center of gravity of the vehicle. For example, DE 10 2007 047 037 A1 discloses a motor vehicle body with two opposing rear side frame rails, wherein at least one auxiliary frame and/or one or more cross members can be allocated to the rear side frame rails and secured thereto.
[0005] The side frame rails, the auxiliary frame or the cross members are here already provided in advance with a number of joints, which are designed and arranged in such a way that one or more correspondingly adjusted aggregates and/or add-on parts can be modularly secured to the side frame rails in proximity to the joints, depending on the equipment currently desired for the motor vehicle rear frame. It is complicated and costly from the standpoint of production and assembly to have available a plurality of different body variants, e.g., in which sheet metal parts for the body must be separately fabricated and conceived for each type of vehicle. In addition to the body structure, motor vehicles exhibit a chassis, which is fabricated parallel to the body in the process of manufacturing the motor vehicle, and joined in its entirety with the preconfigured body in a joining process generally referred to as a marriage. In particular, in the rear area, the chassis exhibits a wheel suspension with lateral, pivoted axle journals, wherein the left and right axle journals are typically coupled by means of a Watt linkage.
[0006] In known vehicle configurations, the Watt linkage is mounted on load-bearing structural components of the body, or pivoted thereto. In this way, a Watt linkage coupling is established in the area of a cross member structure that joins the two frame rails of a motor vehicle body in the transverse direction (y) of the vehicle. A plurality of individual assembly steps involving the use of several components is required precisely for attaching and assembling a Watt linkage to the body.
[0007] Therefore, at least one object is to provide a rear cross member of a motor vehicle body that is improved in terms of weight and installation variability, and distinguished by both lower production and assembly costs and a reduced weight. At least another object is to create a rear vehicle platform-independent rear cross member structure that can be individually adjusted to different vehicle types and equipment, and is easy to assemble. In addition, the process of joining the motor vehicle body and chassis is to be simplified and optimized, while economizing on assembly steps and reducing the number of components required for assembly. In addition, other objects, desirable features, and characteristics will become apparent from the subsequent summary and detailed description, and the appended claims, taken in conjunction with the accompanying drawings and this background.
SUMMARY
[0008] This object is achieved with a rear floor module, with a motor vehicle body, as well as with a motor vehicle. The rear floor module is designed for a motor vehicle body, and meant to arrange between two rear frame rails of the vehicle body running essentially in the longitudinal direction of the vehicle. The floor module here exhibits a floor tray essentially running flatly between the frame rails of the vehicle body, as well as at least one integrated cross member. The cross member integrated in the floor tray can here be separately connected with the frame rails for transmitting mechanical forces, and further exhibits a connecting structure to which at least one component of a vehicle chassis can be directly secured. Instead of a separate Watt linkage coupling to the motor vehicle body to be realized in several assembly steps and using several attachment components, the Watt linkage can be indirectly coupled to a cross member integrated in a rear floor module.
[0009] The floor module can here be connected with a Watt linkage in advance, in particular to create a preconfigured installation unit comprised of the floor module and Watt linkage, which can also be arranged on the vehicle only following the marriage of the body and chassis. The floor module is here preferably designed as a structurally reinforced plastic component, if necessary as a hybrid component with structurally reinforcing metal inserts. The floor module is provided for connection with the load-bearing structural components of the motor vehicle or its body only when the vehicle is in the final assembly stages. Because the rear floor module is provided, the assembly process can be simplified by reducing the number of parts.
[0010] In addition, the error proneness of the assembly process can be reduced. This is because, by mounting the cross member on the frame rails, the floor tray also achieves the final assembly position envisaged for it and vice versa. Differently configured floor modules that each exhibit one or more cross members varyingly positioned in the longitudinal direction (x) of the vehicle can also always be secured to the frame rail in largely an identical manner. Therefore, no redundant joints for the floor module or cross member need to be provided on the body, in particular on the frame rail.
[0011] A first development provides that at least sections of the floor tray and/or cross member be made out of plastic. The floor tray and/or cross member preferably is essentially of plastic. Using a plastic material for the floor tray and/or cross member permits a decrease in overall vehicle weight, and can to this extent help cut fuel consumption by the vehicle. The configuration as a plastic module also enables a flexible adjustment of the position of the cross member within the floor module and/or relative to the frame rails. As a whole, this makes it possible to provide a platform and vehicle type-independent assembly concept. The respective floor module must be adjusted to varyingly partitioned installation spaces in the vehicle, and correspondingly varying positions of the cross member, in particular with respect to the longitudinal direction of the vehicle.
[0012] A further development provides that the floor tray and cross member is designed as a single piece. The floor tray and cross member are preferably fabricated as an injection molded plastic component. Depending on the existing installation situation, a plurality of differently configured floor modules individually tailored to a respective vehicle type or manufacturing platform can here be prefabricated, for example in a plastic injection molding process. For example, the ranges of different floor modules obtainable as a result can vary with respect to the position of its/their cross members, to account for the in part differing installation circumstances for the respective vehicle or vehicle type.
[0013] It further proves advantageous for at least one lateral boundary edge of the floor tray to exhibit an attachment profile adjusted to the geometry of the allocated frame rail for attachment to at least one of the frame rails. For example, an attachment profile projecting from the lateral edge of the floor tray can be provided, e.g., which comes to abut the top side, bottom side or interior lateral wall of the allocated frame rail, and can there be joined with the latter.
[0014] In relation to the vertical direction (z) of the vehicle, the preferably structurally reinforced cross member extends above and/or below the lateral attachment profile of the floor tray. It can further lie within the height range of the floor tray and/or its attachment profile. In particular, given an embodiment in which the cross member comes to lie under the floor tray or under or adjacent to a lateral attachment profile, the cross member can be connected with a coupling structure for receiving the chassis components that naturally come to lie under and/or overlap the floor module.
[0015] Because the end sections of the cross member integrated in the floor module that lie in the transverse direction of the vehicle come to lie under the frame rails, the frame rails and floor module side cross member can exhibit a comparably large, reciprocal coupling area extending over nearly the entire width of the cross member and/or frame rail, which enables as torsion-resistant and rigid a force-transmitting connection as possible between the frame rails and cross members. In this regard, the rear floor module performs a dual function. Its floor tray fills out the gap between the rear side frame rails extending essentially in the longitudinal direction of the vehicle. By contrast, the cross member integrated into the floor module acts as a structurally reinforcing component, but given the one-piece configuration of the floor tray and cross member, is preferably attached together with the floor module to the vehicle body, preferably to its rear frame rails.
[0016] In another embodiment, the cross member exhibits a connecting structure for directly linking at least one chassis component to the cross member, and hence to the floor module. As a result, the preferably structurally reinforced cross member can also act as a receptacle or linking point for the components of a chassis to be secured to the body. Instead of an individual linking structure to be separately joined with the frame rails of the body, the former can in the present embodiment be directly integrated in the cross member preferably designed as an injection molded plastic component.
[0017] In addition, it may prove advantageous to provide a depression for accommodating the at least one chassis component in a bottom side of the floor module, roughly bordering the cross member in the longitudinal direction of the vehicle. Because the floor module is preferably designed as an injection-molded component, it can exhibit nearly any geometric contour without any additional outlay in terms of structure or assembly, and hence be adjusted to the later location and position of additional vehicle components, in particular chassis components.
[0018] In a further development of the above, it can also prove especially advantageous that the cross member be designed to receive or mount a Watt linkage of the chassis. This advantageously eliminates the need for an individual or separate linking structure on the body-side rear frame rails for receiving a Watt linkage. When a final assembly position is reached, the Watt linkage preferably comes to lie in the depression of the floor module adjacent to the cross member. Because the floor module receptacle provided for the Watt linkage also directly borders the cross member, a structurally reinforcing element recessed or embedded in the cross member material can exhibit a metal sleeve or bushing for receiving the Watt linkage bearing. It here also proves advantageous for the sleeve or the connecting structure to be provided on the cross member to extend essentially in the vertical direction (z) of the vehicle, so that the Watt linkage can be screwed to or otherwise connected with the cross member during the marriage of the body and chassis in the longitudinal or vertical direction of the vehicle. However, it is also conceivable to separately arrange or secure the preconfigured Watt linkage on the floor module already before the marriage of body and chassis, and only functionally connect the Watt linkage with the chassis during installation of the floor module.
[0019] In another embodiment, the cross member integrates a sleeve aligned essentially in the longitudinal direction (x) of the vehicle or vertical direction (z) of the vehicle, which is used to accommodate a bearing or bearing bolt of the Watt linkage of the chassis. The alignment of the sleeve here corresponds either to the alignment of the Watt linkage bearing and/or the direction of assembly or attachment envisaged by the process for manufacturing the motor vehicle. The floor module essentially designed as an injection molded plastic component can be used to adjust the configuration of the cross member linking area of the floor module to prescribed installation conditions in a largely variable and nearly cost-neutral manner.
[0020] A further development of the above can also provide that that a receptacle that comes to lie flush with the carrier-side sleeve or reinforcing structure be incorporated in a cheek adjacent to a depression of the floor module in a longitudinal direction. As already the case with respect to the carrier-side sleeve, the receptacle is used to link or mount the bearing of the Watt linkage. If an installation in the vertical direction of the vehicle is to be strictly observed, it can also be provided as a departure from the above that a linking structure already be furnished in the area of the Watt linkage bearing, on the chassis side, as it were, which can be mounted, preferably screwed, in the z-direction into another linking structure corresponding thereto, for example on the cross member and/or spaced apart from the latter in a longitudinal or transverse direction of the vehicle.
[0021] In another embodiment, the end sections of the cross member lying in the transverse direction of the vehicle project laterally from the floor tray of the floor module, and its projecting end sections exhibit a supporting surface that is provided or to be provided with an attachment means, with which the cross member can be supported from below by the respectively allocated frame rail of the body once it has reached its final assembly position. The supporting surface advantageously exhibits a shape corresponding to the outer contour of the allocated frame rail, thereby allowing the supporting surface and bottom side of the allocated frame rail to mutually about each other over as large an area as possible, roughly on the entire surface. The frame rail and/or supporting surface can further be provided with individual attachment means, like screws, rivets, screw holes, and/or welding nuts, to structurally connect the floor module preferably designed as an injection molded plastic component with the frame rails fabricated out of sheet metal shells.
[0022] In the case of a plastic floor module, the connection segments, in particular, those for receiving screws can be provided with metal sleeves recessed or embedded in the plastic material or local metal inserts to impart sufficient stability to the plastic component, in particular in its connecting regions bordering other components of the body.
[0023] In another embodiment, a transverse web running between the opposing attachment profiles on the edge side extends on the top side of the floor module at roughly the height of the at least one cross member in relation to the longitudinal direction (x) of the vehicle. This transverse web is able to impart additional stiffness to the floor module. In particular, the floor module in the transverse web area can be provided with a structurally reinforcing metal insert, so as to impart an inherently enhanced strength and structural rigidity to not just the cross member, but also to the tray-shaped floor module. The transverse web can also be regarded as an upwardly directed elongation of the cross member that passes through the floor module.
[0024] It can generally be envisaged in further embodiments of the floor module that at least one structurally reinforcing metal insert be provided, at least in the area of the at least one cross member, in the area of at least one edge-side attachment profile, in the area of a transverse web, in the area of the at least one floor tray and/or in the area of the connecting structure for the chassis component. The metal insert(s) can here exhibit a geometry adjusted to the respective purpose and envisaged installation site, and in particular structurally reinforce the linking or attachment points provided on the floor module.
[0025] In order to screw the floor module with the adjacent body and/or chassis components, individual sleeves or metal threads are advantageously incorporated, which make it possible to screw or bolt corresponding connecting sites with the adjacent body components. It can further be provided that the floor module, in particular its cross member, but also the floor tray, be designed as a plastic reinforced with fiber or in some other way, in particular as a glass or carbon fiber-reinforced plastic, so that any transverse forces and moments acting on the cross members can be absorbed and, if necessary, diverted to adjacent body components, such as the rear frame rails. Possible plastic materials here include preferred thermoplastic elastomers, in particular those based on polypropylene (PP) or polyamide (PA), as well as duroplastics, in particular unsaturated polyester resins (UP). In addition, the floor module, in particular the area of its cross member, can incorporate structurally reinforcing ribs, which preferably can exhibit a parallel, perpendicular, crossed, lattice-like or hexagonal structure relative to the longitudinal and/or transverse direction of the cross member.
[0026] Another embodiment further provides that the floor tray of the rear floor module exhibits at least one depression for accommodating vehicle components and functional parts, as well as for accommodating a spare wheel and/or battery and/or at least one fuel container, for example an oil or liquid gas container. In particular, in hybrid or purely electric-powered vehicles, a depression designed for holding accumulators can be provided in the area of the floor tray. For example, the floor tray can be divided into two preferably coherent sections by the cross member located above the tray level. For example, the division can provide that one or more receptacles upstream from the cross beam in the traveling direction be furnished for one or more batteries or accumulators, and/or that the floor module incorporate a spare wheel well lying behind the at least one cross member.
[0027] The arrangement of the cross member along with its geometric configuration and dimensioning are preferably geared toward optimizing the available installation space. Depending on whether and to what extent the motor vehicle is to be provided with a spare wheel, accumulators, batteries and fuel tanks, or other functional components, such as a retractable load carrier in the rear area, the position of the cross member as viewed in the longitudinal direction of the vehicle can be adjusted by providing a rear floor module made of plastic individually tailored to the respective installation requirements. In this regard, a respective adjustment of the actual body and frame rails is no longer required.
[0028] Another embodiment provides a motor vehicle body that exhibits at least two side frame rails and at least one floor module arranged between the frame rails. The opposing end sections of a cross member extending between the frame rails and integrated into the floor module are arranged on the frame rails, and there separately connected with the respective frame rails. This floor module can exhibit all of the aforementioned characteristics and advantages.
[0029] A further embodiment also provides that the two frame rails exhibit several attachment points or attachment sites spaced apart from each other according to a predetermined grid in the longitudinal direction of the vehicle, which correspond with varying cross member positions of floor modules with different configurations. In this regard, a floor module tailored to the respective vehicle configuration can be provided with cross members varyingly positioned in the longitudinal direction of the vehicle, for example, and connected with the frame rails universally furnished with several attachment points, without separately adjusting the frame rails.
[0030] This makes it possible to make adjustments for the most varied of configurations of a vehicle type, which can be designed like a hybrid, with or without a rear luggage rack, a caravan or a limousine, by correspondingly selecting a floor module provided separately for the respective vehicle configurations, without having to introduce changes to the metal or sheet metal components of the body for this purpose, in particular to their rear frame rails. Therefore, the same type of frame rail can be used for the most varied of vehicle configurations. For example, if the vehicle is to be provided with a hybrid or electric motor drive concept, the specific position of the cross member and the module partitioning can be varied, in particular with respect to receiving depressions for emergency or spare wheels, as well as for batteries and/or fuel tanks, by selecting a respective floor module envisaged for the respective vehicle configuration. It is further conceivable for the floor module to exhibit not just one, but several cross members spaced apart from each other, e.g., in the longitudinal direction (x) of the vehicle, which each can be separately connected with the rear frame rails of the body.
[0031] Another embodiment further provides a motor vehicle, which exhibits at least one of the previously described rear floor modules and/or is provided with a previously described body.
BRIEF DESCRIPTION OF THE FIGURES
[0032] The present invention will hereinafter be described in conjunction with the following drawing figures, wherein like numerals denote like elements, and:
[0033] FIG. 1 is a perspective view of a floor module along with a Watt linkage attached thereto;
[0034] FIG. 2 is the view according to FIG. 1 in a possible installation situation on the body of a motor vehicle;
[0035] FIG. 3 is a detailed and magnified view of a Watt linkage mounted as denoted on FIG. 1 ;
[0036] FIG. 4 is a perspective, isolated view of the floor module, viewed at an inclination from the back; and
[0037] FIG. 5 is the floor module according to FIG. 4 viewed from the bottom.
DETAILED DESCRIPTION
[0038] The following detailed description is merely exemplary in nature and is not intended to limit application and uses. Furthermore, there is no intention to be bound by any theory presented in the preceding background or summary or the following detailed description.
[0039] The rear floor module 10 depicted on FIG. 1 , FIG. 2 , FIG. 4 , and FIG. 5 in various configurations and in perspective in different views exhibits a cross member 14 extending essentially in the transverse direction (y) of the vehicle, as well as a floor tray 12 designed as a single piece with the latter. In the embodiment shown, the floor tray 12 is designed as an approximately rectangular surface structure, which can be attached to the side frame rails 54 , 56 of a motor vehicle body shown on FIG. 2 with the edge profiles 18 lying on the outside in the transverse direction (y) of the vehicle by means of passage openings 26 incorporated therein, which in turn are preferably furnished with metal inserts.
[0040] The floor module 10 is further designed to directly accommodate a chassis component, in the present case to attach a Watt linkage 46 , 48 . In this regard, it exhibits a connecting structure or attachment section 40 , on which chassis components 46 , 48 can be directly joined with the floor module 10 . The Watt linkage 46 , 48 running essentially in the transverse direction of the vehicle connects the two axle journals 50 , 52 depicted on FIGS. 1 and 2 , and is attached with a bolt 42 to the cross member 14 of the floor module 10 in the area of a bearing that comes to lie centrally between the frame rails 54 , 56 . In order to accommodate the Watt linkage 46 , 48 , in particular to mount the hinge 45 connecting the two rods 46 , 48 with each other, a sleeve designed to accommodate the bearing bolt 42 is incorporated in the cross member 14 and, if necessary, also in the opposing cheek structure 44 of the receiving depression 24 or there embedded in the plastic component in the area of the cross member 14 , as depicted on FIG. 3 . In particular, the Watt linkage 46 , 48 can be preconfigured and connected with or to the floor module 10 before any marriage of the body and chassis, so that the floor module 10 preassembled with the Watt linkage 46 , 48 can be joined as a structural unit with the body or chassis even after the reciprocal assembly of body and chassis.
[0041] In a magnified view, FIG. 3 further shows that the cross member 14 facing the Watt linkage 45 is provided with a concave indentation 47 that enables the collision-free assembly and mobility of the hinge 45 in the area of the floor module 10 . FIG. 6 further shows how the Watt linkage 45 is bolted by means of a screw, bolt, or nut 16 extending essentially in the longitudinal direction (x) of the vehicle. Also denoted in the depiction according to FIGS. 2 and 4 are corresponding screws or bolts 58 that pass through passage openings 26 . Since the body frame rails 54 , 56 are preferably fabricated as sheet metal shells with the formation of lateral, outwardly or inwardly protruding flange sections, it is provided that the floor module edge profile 18 be bolted to the inside of the flange sections projecting on the frame rail 54 , 56 for purposes of linking the edge profile 18 of the floor module 10 .
[0042] The end sections 28 of the depicted cross member 14 lying in the transverse direction (y) of the vehicle exhibit a structure that laterally projects relative to the floor tray 12 , which exhibits an essentially flat supporting surface 30 with individual attachment holes toward the top, facing a bottom side of the frame rails 54 , 56 . At a lower edge facing away from the supporting surface 30 and shown on FIG. 5 , the cross member 14 exhibits clearance holes 36 allocated to the passage or attachment openings 26 , which make it possible, for example, to bolt an upwardly projecting bolt 58 into the frame rail 54 , 56 or its linking flange through a cross member 14 that is at least regionally hollow or configured with a hollow chamber profile. Provided toward the front in the traveling direction (x) adjacent to the supporting surface 30 of the cross member 14 is a roughly circular recess 34 , which serves to accommodate a suspension strut. Another front, lateral flange section 32 extends the supporting surface 30 upstream from this recess 34 , and just as the supporting surface 30 , can be directly joined with the bottom side of an allocated frame rail 54 , 56 , preferably bolted thereto.
[0043] The rear section of the floor module 10 shown on FIG. 1 , FIG. 2 , FIG. 4 , and FIG. 5 exhibits a depression configured like a spare wheel well, in which an attachment dome 20 is provided for securing the spare wheel. At the front, the spare wheel well borders a transverse web 22 that roughly coincides with the position of the cross member 14 lying below in relation to the longitudinal direction (x) of the vehicle. Another depression 24 resembling a pocket is situated in front of the transverse web 22 , and can preferably be used to accommodate other functional components, such as one or more vehicle batteries, fuel tanks, or similar energy-storing modules.
[0044] The transverse web 22 can also extend somewhat more broadly in the longitudinal direction (x) of the vehicle than the cross member 14 . In this way, a depression 62 that approximately passes through the floor module 10 in the transverse direction (y) of the vehicle can be formed on the bottom side of the floor module 10 shown on FIG. 1 between the cross member 14 and a side cheek 44 of the receiving depression 24 facing the cross member, and be provided for accommodating a Watt linkage 46 , 48 , as shown on FIG. 1 , FIG. 2 and FIG. 3 .
[0045] FIG. 2 schematically denotes individual attachment sites 64 in different positions in the longitudinal direction (x) of the vehicle, on which one or more cross members 14 of varyingly configured floor modules 10 can be arranged with respectively different cross member positions. In this way, the installation space can be adjusted to the respective vehicle-specific requirements just by using a floor module 10 tailored to a specific vehicle configuration, without having to adjust any other body components, such as the frame rails 54 , 56 . In addition, except for their respective cross member 14 , the varyingly configured floor modules can be secured to the frame rails 54 , 56 of the body in the same exact way, while always retaining a constant outer periphery. Nearly the entire floor module 10 is advantageously designed as an injection molded plastic part and/or hybrid component based on plastic, with locally provided metal inserts. In comparison to cross members 14 made out of steel or metal, this can help minimize the vehicle weight.
[0046] While at least one exemplary embodiment has been presented in the foregoing summary and detailed description, it should be appreciated that a vast number of variations exist. It should also be appreciated that the exemplary embodiment or exemplary embodiments are only examples, and are not intended to limit the scope, applicability, or configuration in any way. Rather, the foregoing summary and detailed description will provide those skilled in the art with a convenient road map for implementing an exemplary embodiment, it being understood that various changes may be made in the function and arrangement of elements described in an exemplary embodiment without departing from the scopes set forth in the appended claims and their legal equivalents. | A rear floor module is arranged between two rear frame rails of a vehicle body running essentially in the longitudinal direction of the vehicle. The floor module includes, but is not limited to a floor tray essentially extending flatly between the frame rails and at least one integrated cross member, which is configured for separately connection with the frame rails for transmitting mechanical forces, and which is provided with a connecting structure to which at least one component of a vehicle chassis can be secured. | 1 |
BACKGROUND OF THE INVENTION
This invention relates to crimping apparatus and more particularly relates to a tool of this type for crimping a connector sleeve to a stranded cable.
Generally, a crimping tool must be capable of exerting sufficient pressure on several surfaces of a connector sleeve to cause the sleeve walls to be deformed so as to engage and frictionally hold the stripped portion of a cable which has been positioned within the sleeve bore. A crimping tool must not exert pressures in excess of this captivating pressure, since overpressurization often results in both cable strand breakage and connector sleeve splitting, which render the crimped connector useless for its intended purpose.
The crimping tool may also be required to perform other functions ancillary to the crimping process. These functions may include the forming of mounting or bearing surfaces on the sleeve, the forming of the entire connector into a shape as required by mounting volume considerations, the forming of apertures for the passage of mounting hardware through the sleeve or the sleeve and cable, the preventing of the application of excessive force in order to minimize distortion of a pre-formed sleeve portion or surface or the maintaining of a particular shaped surface or section while pressure is applied to adjacent surfaces or sections.
The crimping tool may, additionally, be required to establish and hold the connector sleeve and cable in a rigid relationship to one another and to the crimping tool. This positioning apparatus complicates the crimping tool and a preferred tool should be operable without elements utilized solely for holding the connector sleeve and the cable.
Crimp-type connectors have been formed with a flat portion having a through aperture, to allow passage of mounting hardware, and a tube, with its axis displaced above the plane of the flat portion, into which a cable end is placed. This offset tube is then crimped to the cable end by a tool which applies opposed forces of a magnitude sufficient to press the inner wall of the tube into intimate engagement with the cable strands. Large and often abrupt forces are generated by the crimping tool and the cable strands are often deformed and even nicked or severed by the crimping operation. The crimping tool must be designed to prevent contact with the flat portion of the connector during the crimping operation or the large forces exerted during crimping will be transmitted to that portion and will distort the mounting hardware aperture and the flat contact surface to such an extent that the crimped connector cannot be used at the intended connection surface.
Other crimp-type connectors have been formed by crimping a portion of tube to a cable end and then shearing the mounting hardware passage through the crimped tube and cable in a single operation of the crimping tool. Shearing a cylindrical tube containing a cable causes strands to have less high-pressure contact with the entire tube interior and results in unsatisfactory electrical contact between cable and mounting surface. The force necessary to shear the tube and the cable is usually obtained from explosive expansion, requiring that a relatively complex and massive tool be used and necessitating that the tool hold both tube and cable firmly in position so as not to be prematurely ejected from the tool and thereby create a hazardous condition.
A more compact and conductive connector is formed by inserting a cable end into a sleeve having co-aligned apertures. A passage is formed by displacing the cable strands from the region defined by a line extending between the two apertures. As the cable strands are displaced and the apertures in the wall of the sleeve have been previously formed, no shearing operation is necessary. The sleeve may now be crimped to the formed cable by the application of opposed forces along the entire exterior length of the sleeve, resulting in a high conductivity electrical connection. The need for abruptly generated forces is eliminated and relatively slow and steady engagement of the crimping tool may be utilized. It is desirable that the piercing portion of the tool remain within the passage formed in the cable during the crimping operation so that the passage shape is not altered. Because of the requirement for maintaining the position of the piercing portion, the crimping tool must be constructed in such a manner that the portions of the tool exerting the crimping force are unaffected by the piercing portion, to prevent the formation of a loose contact between the connector sleeve and the cable strands in the immediate vicinity of the mounting hardware passage. This is exactly that region of the connector at which firm contact is desired so as to provide the shortest and, therefore, the lowest electrical resistance path from the cable through the connector sleeve to the terminal to which the connector is to be mounted. The proper crimping tool for a connector of this type must provide this crimping pressure in the region immediately adjacent to the aperture while forming as large a crimped surface as possible for contact with the mounting surface and also preventing the collapse or return movement of the cable strands into the mounting hardware passage.
SUMMARY OF THE INVENTION
A crimping tool for the above described type of connector is described hereinafter.
To provide the necessary piercing of the cable and the necessary crimping pressure upon the connector sleeve while maintaining the integrity of the mounting hardware passage and preventing the application of excessive crimping pressures to the connector sleeve, the crimping tool in accordance with the invention has a piercing portion extended from the crimping portion of a first member which can be moved towards the crimping portion of a second member. The crimping portion of the second member is provided with a recess to receive the piercing portion of the first member such that the members may continue to come together until the opposing crimping portions have moved to a position which produces the required crimping pressure upon the sleeve of a stranded cable connector inserted between the two opposed crimping portions. An adjustable stop is provided in one member to bear against a buttress portion on the other member, thereby limiting the minimum distance between the crimping portions of the first and second members. The crimping tool is also provided with means for indicating the magnitude of crimping force produced on the connector sleeve.
The novel crimping tool set forth hereinabove has the advantage that it permits the piercing portion to form and maintain the mounting hardware through-passage while the crimping portions apply the pressure necessary to press the sleeve wall against the cable, forming flat portions for connector contact over the entire length of the sleeve surface including that area immediately adjacent to the mounting hardware through-passage. The crimping tool is easy to manufacture and does not require complex or massive components.
Accordingly, it is the primary object of the present invention to provide a novel crimping tool for forming stranded cable connections.
Another object of the present invention is to provide a crimping tool of the type described herein which is compact, yet embodies all the desirable mechanical features required for crimping a stranded cable connector.
A further object is to provide a crimping tool of the type described characterized by its ease of manufacture at low cost and the simplified crimping operation resulting from the use of the tool.
These and other objects of this invention will become apparent from the following description of the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevation of a crimping tool in accordance with the teachings of the instant invention;
FIG. 2 is a partially-sectionalized view in side elevation of the crimping tool in the open position and embodying the teachings of the invention and further showing a connector sleeve and stranded cable in the positions occupied preparatory to the passage forming and crimping operations;
FIG. 3 is a partially-sectionalized view in side elevation of the crimping tool of FIG. 2 in the closed position and further showing the completed stranded cable connector formed by the tool;
FIG. 4 is a partially-sectionalized view in side elevation of a portion of a crimping tool in accordance with the invention and showing one embodiment of a force measurement device used therewith; and
FIGS. 5, 6 and 7 are side elevations of alternate embodiments incorporating the teachings of the invention.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIG. 2, a bare stranded cable portion 10 of an insulated cable 12 is positioned within a metallic connector sleeve 20 which is to be crimped to the end of cable 12. Connector sleeve 20 is tubular and of known diameter, although the size of the connector sleeve is variable dependent upon the particular diameter stranded cable 10 that is chosen. Connector sleeve 20 includes two diametrically co-aligned apertures 21 and 22 formed in connector sleeve 20.
Referring to FIGS. 1 through 4, crimping tool 30 in accordance with the invention comprises a first member 31, a second member 32 and pivot means 33 to allow the cooperating ends of members 31 and 32 to be moved towards one another. The second member 32 includes a crimping portion 34 at one end, against which the conductor sleeve 20 is positioned. The first lever member 31 includes a cooperating crimping portion 35, which will be generally parallel to crimping portion 34 when connector sleeve 20 is properly crimped. The surface length of crimping portions 34 and 35 are preferably longer in length than conductor sleeve 20. In accordance with the invention, piercing portion 36 extending from portion 35 is cylindrical in cross-section and terminates at its free end with a gently sloping conical point 37. A recess 38 is formed in crimping portion 34 to receive the point 37 during the latter phase of the crimping operation.
It is desired to establish a minimum spacing between crimping portions 34 and 35 to avoid splitting conductor sleeve 20 or breaking strands of cable 10 and to obtain flat, parallel surfaces on the exterior of the conductor sleeve 20. A limit buttress portion 42 is formed upon the first lever member 31. An adjustment screw 39 is threadably engaged within a tapped aperture 40 through screw buttress portion 41 and through the second member 32 upon which screw buttress portion 41 is formed. Adjustment screw 39 is rotated into, or out of, tapped aperture 40 to extend an adjustable distance from screw buttress portion 41 such that during a crimping operation the surface 39a of adjustment screw 39 will engage the surface 42a of limit buttress portion 42 to prevent the application of excessive crimping pressure to connector sleeve 20. By this mechanism, a pair of flat parallel surfaces are provided on sleeve 20 without splitting the connector sleeve or breaking cable strands through overpressure.
In a typical application, connector sleeve 20 is to be crimped to stranded cable 10 and an aligned passage for mounting hardware is to be formed in the stranded cable so as to be aligned with pre-formed apertures 21 and 22. A portion of insulation sleeve 12 is stripped away to expose an end portion of stranded cable 10, which end portion is inserted into the bore of the connector sleeve 20. The adjustment screw 39 is rotated into, or out of, tapped aperture 40 until the distance between surfaces 39a and 42a of the adjustment screw 39 and the screw buttress 41 are set to a predetermined position, to allow the crimping portions 34 and 35 to press the interior surface of sleeve 20 into intimate engagement with the adjacent strands of cable 10 and form a firm frictional hold. This distance is dependent on, but less than, the diameter D of the stranded cable 10 plus twice the wall thickness T of the connector sleeve 20.
The ends 34 and 35 of crimping tool 30 are separated so that connector sleeve 20 may be generally positioned against the surface of crimping portion 34 without mechanical interference with point 37. Force is applied to members 31 and 32, at their ends opposite to the crimping portions 35 and 34 respectively, while connector sleeve 20 is rotated about the stranded cable 10 to align point 37 with aperture 21 to enable point 37 to engage the top surface of the stranded cable 10. Force is now firmly applied to move the point 37 of the piercing section 36 through stranded cable 10 and to preferably transversely displace rather than cut through the individual strands of cable 10 thereby forcing them outward into the empty annular space between the interior surface of the loosely fitted connector sleeve 20 and the exterior of the stranded cable 10. Point 37 also passes through connector sleeve aperture 22 and is received within clearance recess 38 while piercing portion 36 fills the formed passage to maintain the configuration of the formed passage while the sleeve and the cable are crimped by tool portions 34 and 35.
Clamping portion 35 now bears on the entire upper exterior surface of the conductor sleeve 20. Continued application of force causes pressures to be transmitted along the entire length of the conductor sleeve 20 by both clamping portions 34 and 35, substantially simultaneously and equally. The applied force deforms conductor sleeve 20 until the limit buttress surface 42a engages surface 39a of the adjustment screw 39 and the spacing between clamping portions 34 and 35 is at its desired minimum. The interior surface of connector sleeve 20 has been sufficiently pressed onto the stranded cable 10 and a firm frictional crimp with flat surfaces along the entire exterior length of the connector sleeve is obtained. The members 31 and 32 are now moved apart from one another and the completed connector-wire assembly is removed from the piercing portion 36, which has retained the mounting hardware passage as well as holding the cable strands in their displaced positions to thereby fill the interior volume of the connector sleeve until the crimping operation is completed.
It is also desirable to indicate the magnitude of crimping force applied by crimping portions 34 and 35 to assure that the interior surface of conductor sleeve 20 has been properly pressed onto cable portion 10. A force measurement device 44 used as part of a preferred embodiment of the present invention includes a hollow enclosure 31a formed at the end of member 31 aligned with crimping portion 34. A cylindrical member 45 having one end thereof forming cooperating crimping portion 35, with piercing portion 36 extended therefrom, is slidably extended through a first aperture 31b formed in the enclosure wall and positioned whereby piercing portion 36 and recess 38 cooperate as described above. A cylindrical indicator shaft 46 axially extends from the center of an annular disc 47, which disc is attached to the free end of member 45 and has a diameter greater than the diameter of aperture 31b, to retain member 45 when the crimping tool is not in use. Shaft 46 is slidably extended through a second aperture 31c formed in the enclosure wall opposite first aperture 31b. A spring 48 biases annular disc 47 toward the enclosure wall having aperture 31b formed therethrough. Indicator shaft 46 includes a sequence of force calibration marks 46a, the predetermined values of which are dependent upon the spring constant of spring 48 and the length of shaft 46 projecting through aperture 31c. In use, crimping portions 34 and 35 are moved toward one another until the predetermined proper one of force calibration marks 46a project through aperture 31c even with the exterior of enclosure 31a, to establish a maximum spacing between crimping portions 34 and 35.
FIGS. 5, 6, and 7 show alternative embodiments 30', 30" and 30'" of the crimping tool. In the embodiment of FIG. 5, the pivot means 33 has been placed at one end of each of the first and second members 31 and 32 to allow the members to move towards one another and the crimping portions 34 and 35 have been made with a rounded cross-section. The remaining structure is substantially as shown in FIG. 1. In this embodiment, a large mechanical advantage is always achieved. The connector sleeve, with an inserted cable end, may be positioned in the crimping portions 34 and 35 and yet enter the tool in a plane perpendicular to the axis of shaft 36 but at an angle to the members 31 and 32. This embodiment is particularly useful in applications in which a relatively thick cable is being utilized, requiring a large force to be applied to form the passage and to crimp a relatively thick sleeve wall to that cable, or in which the crimping tool must be utilized in a confined space around the cable end, such as the riser trough behind a circuitbreaker panel, in which the tool must be positioned at an angle with respect to the cable direction and force multiplication is required when the tool operator cannot unaidedly generate sufficient force, because of his awkward position.
In the embodiment of FIG. 6, a tool 30" is shown which uses another means for moving members 31 and 32 towards one another. The pivot means of tools 30 and 30' is replaced by the threaded shaft 51 and tapped aperture 50, extending through the arm 62 of U-shaped member 61. The first member 35 is affixed to shaft 51 and comprises the piercing portion 36 at one end of the first member, joined to the first crimping portion 35. A disc 53 is secured to shaft 51 and a rod opening 54 is diametrically drilled through shaft 51 at a position above the top surface of the disc 53. A rod 60 may be inserted into opening 54. The remaining structure is substantially as shown in FIG. 1. In this embodiment threaded shaft 51 is rotated by manipulation of disc 53 to move the first and second crimping portions toward one another, to pierce the cable and crimp the sleeve. If more crimping force is desired, one end of rod 60 is inserted into the rod opening 54 and the resulting large mechanical advantage multiplies the force applied to the other end of the rod 54. This embodiment is suitable for semipermanent mounting, as in a location where large numbers of cable-connector assemblies are to be formed over a period of time.
In the embodiment of FIG. 7, a crimping tool 30'" uses pneumatic or hydraulic pressure for moving crimping portions 34 and 35 towards one another. U-shaped member 61 includes a first arm 32 having a crimping portion 34 with a recess 38 formed therein. A second arm 62 includes a pressure enclosure 65 in which is mounted a piston 66 having member 31, cooperating crimping portion 35 and piercing portion 36 formed at an end thereof, which end 66a is downwardly extended as high pressure gas or fluid is forced into enclosure 65 via pipe 67 connected to a pressure source. Arm 62 contains a recess 62a, which recess closely cooperates with piston shaft 66b to guide piercing portion 36 along a straight line toward recess 38. Pressure gauge 70 and/or pressure alarm switch 71 are connected to enclosure 65 by tube 72. Pressure switch 71 may be utilized to sound a buzzer or other suitable alarm, or to shut a valve (not shown) in pressure pipe 67, when the desired pressure is reached and the required force has been produced on connector sleeve 20 by crimping portions 34 and 35. This embodiment is suited for permanent mounting, as in a central factory producing very large quantities of cable-connector assemblies.
It can be seen from the foregoing description that the present invention provides a novel crimping tool for use in substantially simultaneously piercing and crimping a connector sleeve and stranded wire, where a passage is formed in the stranded cable and its shape is maintained during application of crimping forces sufficient to distort the entire length of the connector sleeve walls and cause frictional crimp between the entire sleeve and the cable.
Although the present invention has been described in connection with several preferred embodiments thereof, many variations and modifications will now become apparent to those skilled in the art. It is, therefore, preferred that the present invention be limited not by the specific disclosure made herein, but only by the appended claims. | A crimping tool for use with a stranded cable connector having co-aligned sleeve openings, including a first member with a crimping portion; a piercing portion extended from the first crimping portion; a second member with a crimping portion and a recess for receiving the piercing portion and means to move the first and second crimping portions towards one another. A loose fitting cable connector sleeve with an inserted cable portion is positioned on the second crimping portion and the piercing portion is moved through the sleeve openings, thereby displacing the cable strands toward the interior wall of the sleeve, and forming a through passage. Movement of the cooperating crimping portions continues until the crimping portions have formed flat surface areas along the entire length of the sleeve thereupon and further movement is limited by an adjustable stop. | 7 |
BACKGROUND OF THE INVENTION
The present invention relates to magnetic materials and in particular to an alloy which when fully processed has a major portion of the grains exhibiting a (110)[001] orientation and is characterized by the grains having undergone a secondary recrystallization.
In the past, oriented electrical steels have been characterized usually by the addition of sufficient silicon to close the γ loop to such an extent that heating a steel containing 3% silicon with sufficiently low carbon content to a temperature of about 1200° C. resulted in heating said materials in the all α field, the loop having been restricted sufficiently that the alloy would avoid any phase transformation upon heating or cooling to such elevated temperatures.
Commensurate with the addition of 3% silicon to the underlying basic iron was the further factor for the necessity for the control of the manganese and sulfur contents such that a sufficient degree of manganese sulfide was required to be present in the alloy prior to the final high-temperature anneal. During such high-temperature anneal it was the function of the manganese sulfide to inhibit less favorably oriented grains in order to permit the grains having a (110)[001] orientation to grow at the expense of less favorably oriented grains. This occurred during heating of the material to the final high-temperature anneal.
However, once the desired orientation was obtained the sulfur content was no longer needed and, in fact, provided a deleterious effect on the overall magnetic characteristics such that in the commercial manufacture of oriented silicon steels, a sufficiently high temperature was obtained in the final anneal and held for a sufficiently long period of time to dissociate the manganese sulfide into its components and thereby through the use of a dry hydrogen atmosphere, the sulfur content was reduced to acceptably low levels so that the overall combination of magnetic characteristics obtainable in the steel was optimized.
In more recent years a new type of technology has been evolved which employs a different type of inhibitor, namely nitride or certain borides in combination with manganese sulfide utilized in the earlier produced oriented silicon steels. These steels in which the aluminum nitride or other inhibiting element was utilized have been known commercially as the so-called high-B steels. These high-B steels usually had an induction in excess of about 18.8 kilogauss at a magnetizing force of 10 oersted.
One common thread is apparent in these prior art steels and that is that the final heat treatment takes place near 1200° C., a temperature in excess of the α⃡γ transformation temperature for materials containing, for example, less than about 2.5% silicon. Typical of the prior art in which the aluminum nitride was utilized as the inhibiting agent is U.S. Pat. No. 3,287,183 in the name of Taguchi et al. These inventors find that two cold rolling steps must be critically controlled, the first one being within the limitation of 5 to 40%, and the second one being within the range between 81 and 95% reduction in area. In addition, Taguchi et al. required a definite relationship between the sulfur and the acid soluble aluminum together with an intermediate annealing temperature range, none of which the applicants have found to be critical. In fact, applicants have substantially less sulfur and aluminum than recommended by Taguchi et al. and the temperature of their intermediate anneal is usually in the neighborhood of about 850° C., whereas Taguchi et al. recommends 950° to 1200° C.
Another patnet to Sakakura et al. namely U.S. Pat. No. 3,632,456 describes essentially the same composition of matter and the processing which is fairly similar to Taguchi et al. and differing therefrom by requiring the annealing and quenching of the strip material in order to precipitate aluminum nitride. Sakakura et al. also find it necessary for forming a primary recrystallized microstructure in the steel sheet between cold rolling operations. To substantiate the same effect, more elucidation on the rolling schedules as well as the necessity for the precipitation of the aluminum nitride through a specified heat treatment may be found in U.S. Pat. No. 3,636,579 also in the name of Sakakura, et al.
SUMMARY OF THE INVENTION
In contrast to the prior art practices of utilizing relatively high levels of manganese sulfide and aluminum nitride to inhibit the growth of less favorably oriented grains, it has been found that smaller quantities of sulfur and aluminum can be utilized with lower annealing temperatures and thereby allow lower silicon contents which improve the saturation magnetization without unduly inhibiting the volume resistivity and still obtain the oriented crystallographic structure in a secondary recrystallized microstructure. The lower silicon compositions, that is, less than 2% silicon are such that the material upon heating in excess of about 1050° C. will undergo an α to γ transformation. It is believed that where the material undergoes an α to γ transformation the volume of crystals which will obtain the desired (110)[001] orientation in the rolling direction will be substantially smaller if the material is heated above the critical transformation temperature. Yet these high temperatures were heretofore believed necessary in order to obtain the desired degree of orientation and removal of the inhibitor impurities as suggested in the prior art teachings employing either manganese sulfide or aluminum nitride. The method of the present invention is also applicable to compositions having a closed gamma loop if the amount of aluminum, nitrogen, manganese and sulfur are controlled within the limits as set forth herein.
In the present invention, the final anneal is at a sufficiently low temperature that the material will not be exposed to a temperature above the critical temperature and yet will exhibit the (100)[001] orientation and a secondary recrystallized microstructure.
The present invention relates to an alloy which has a microstructure characterized by secondary recrystallization. In this respect the alloying components include 0.010% to 0.050% carbon, less than about 3.5% silicon, up to about 2% of a volume resistivity improving element, aluminum 0.005% to 0.015%, manganese 0.03% to 0.30%, nitrogen 0.003% to 0.015%, sulfur 0.003% to 0.012% and the balance iron with incidental impurities. The alloy when fully processed will exhibit a (110)[001] orientation and the alloy will also have a secondary recrystallized microstructure.
After the melt of the desired composition is made, it is thereafter cast and following casting the material is hot-worked preferably with a finishing temperature within the range between about 800° C. and about 1000° C. Following hot-working the material is cold-worked in one or more operations to finish gauge with an intermediate α phase anneal being interposed between each successive cold-working operation. Finally the material of finish gauge is heated to a temperature below the α-Γ transformation temperature, preferably within the range between about 850° C. and about 1050° C. for alloys containing less than 2% silicon and 1100° to 1200° C. for higher silicon content alloys. As thus manufactured, the alloy is suitable for use as a core material in electromagnetic inductive apparatus, for example, transformer cores.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The alloy of the present invention may be made in any of the well-known manners for making steel and the preferred method is to melt the components in an electric arc furnace. It, of course, will be understood that such melting procedures as those of a basic oxygen furnace or an induction furnace can also be utilized in manufacturing the alloy of the present invention.
The components in the requisite amounts are melted and preferably while the alloy is in the molten condition it is vacuum-degassed and desulfurized prior to pouring either into a tundish for continuous slab casting or for the pouring of individual ingots.
In order to more clearly demonstrate the present invention reference may be had to TABLE I hereinafter which lists the chemical composition of heats A1, A2 and B.
TABLE I______________________________________Heat* % Si % Mn % S % C % Al** % N % O______________________________________A1 0.97 0.12 0.007 0.014 0.012 0.008 0.006A2 1.07 0.07 0.008 0.014 0.012 0.009 0.006B 0.87 0.08 0.004 0.016 0.006 0.005 0.005______________________________________ *Mill analysis **Acid soluble aluminum
Heats A1 and A2 were melted in a commercial 150-ton electric arc furnace, vacuum-degassed and desulfurized prior to pouring into a number of ingots. Heat B was melted in a 10-ton electric arc furnace using previously desulfurized iron. This heat was also vacuum-degassed and thereafter was poured into a single ingot. The ingots from these heats were, after solidification, soaked and rolled in a commercial rolling mill. Two ingots from heat A1 were rolled to about 0.175 inch thick hot bands in the mill after the ingots were first slabbed and initially rolled from about 1300° C. One hot band had a finishing temperature of about 950° C. and the other had a finishing temperature of about 840° C. Samples from both hot bands were processed as follows: after pickling, the material was cold rolled to 0.080 inches and thereafter given an intermediate anneal followed by a second cold rolling to a thickness of 0.020 inches, another intermediate anneal and a final cold rolling to finish gauge of a thickness of 0.006 inches. Thereafter the material was given a final box anneal for 48 hours at 900° C. in dry hydrogen.
Under one cold rolling schedule, the hot band material was given a 5 hour box anneal at 850° C. in dry hydrogen prior to cold rolling. In this cold rolling schedule the first intermediate anneal was also a 5 hour box anneal and the second intermediate anneal was a 1 hour box anneal. All intermediate box anneals were performed at approximately 850° C. in dry hydrogen. In the other case, 2 to 3 minute strip intermediate anneals at 900° C. in dry hydrogen were given only between cold rolling stages; there was no anneal prior to cold rolling. All samples as thus processed had essentially complete secondary recrystallization to a (110)[001] orientation after final annealing
TABLE II______________________________________Hot-workFinish 60 Hz LossesTemp. inter. H.sub.c B.sub.10 P.sub.c15 P.sub.c17 P.sub.c18 P.sub.c19(°C.) Anneals (Oe) (kG) (W/lb) (W/lb) (W/lb) (W/lb)______________________________________950 Box 0.145 19.3 0.62 0.79 0.91 1.07950 Strip 0.162 19.2 0.63 0.80 0.92 1.09840 Box 0.140 19.9 0.60 0.74 0.82 0.94840 Strip 0.154 19.4 0.59 0.75 0.86 1.01______________________________________
Reference to TABLE II is made for a comparison for the magnetic characteristics exhibited by the materials after being processed as above described. It should be noted that all of the samples have a high B 10 value, a low coercive force and the 17 and 18 kilogauss core less values are comparable to commercially produced oriented silicon steel containing a minimum of about 3% silicon.
An ingot from heat A2 was hot rolled in the mill to 0.180 inches from a slab which was heated to a temperature of about 1300° C. and the finishing temperature of the hot-rolling operation was about 1000° C. The coil was rolled thereafter to 0.006 inch final gauge in the mill using the same process as above described with the exception that a 1- to 2-minute intermediate strip anneal at about 880° C. was interposed between each cold-working operation. Thereafter the cold-rolled samples were annealed for about 90 hours in dry hydrogen in a furnace with a gradient from about 850° C. to 1050° C. Extensive secondary recrystallization to the (110)[001] texture was observed in the temperature range between 900° and 950° C.
An ingot from heat B was also slabbed in the mill and the samples were hot rolled so that they had finishing temperatures of about 900° C., 1050° C. and 1200° C. The thickness of the hot rolled material was 0.160 inches. Samples were then cold rolled to 0.006 in using the same process as set forth initially above for heat A1 material with hot anneals being interposed at 850° C. both at the hot-band stage and at all intermediate thicknesses. Thereafter the cold-rolled samples were annealed for 48 hours at 900° C. after the material had been cold worked to its finished gauge thickness. Essentially complete secondary recrystallization was observed in the samples hot rolled at 900° and 1200° C. A smaller grain size, however, was observed in the sample hot rolled so that the finishing temperature was 1050° C.
TABLE III______________________________________Hot Roll 60 Hz LossesFinishing H.sub.c B.sub.10 P.sub.c15 P.sub.c17 P.sub.c19Temp. (°C.) (Oe) (kG) (W/lb) (W/lb) (W/lb)______________________________________ 900 0.15 19.7 0.61 0.79 1.101050 0.18 18.5 0.62 0.85 --1200 0.15 19.7 0.62 0.81 1.12______________________________________
By referring to TABLE III the magnetic characteristics of this latter group of materials is set forth and clearly demonstrates the advantages of the alloy and process of the present invention. Thus, it is seen that good secondary recrystallization textures can be obtained in low alloy iron melted and processed employing commercial facilities. The aluminum and sulfur contents are much lower than required for previously reported processes for obtaining a secondary recrystallized microstructure.
When heat A2 having the chemistry set forth in TABLE I was melted, four of the ingots were inoculated with a nominal addition of 0.6% chromium. The effect of the chromium was sufficiently significant that the alloy without chromium had a resistivity of about 25 microhm-centimeters whereas the ingots in which about 0.6% chromium was added exhibited an improved resistivity of about 28 microhm-centimeters. All four of the chromium-containing ingots were rolled with different hot-rolling parameters to hot-rolled bands as follows:
TABLE IV______________________________________Coil Slab T Finish T Coiling T GaugeNo. (°C.) (°C.) (°C.) (in)______________________________________18 1320 1020 700 0.16119 1320 850 650 0.17220 1160 880 ˜660 0.17821 1160 850 740 0.169______________________________________
Samples from all four hot-rolled bands were thereafter rolled to a final thickness of 0.006 inch by the following process: the hot-rolled material was pickled and then annealed for 5 hours at 850° C., cold rolled to 0.080 inch thickness, annealed for 5 hours at 850° C., cold rolled to 0.020 inch annealed for 1 hour at 850° C., cold rolled to 0.006 inches and thereafter tested. All anneals utilized a dry hydrogen atmosphere. Samples from coils numbered 18 and 20 were rolled to a finish thickness of 0.011 inches by the following process: following pickling of the hot-rolled material it was cold rolled to 0.080 inch thickness annealed for 1 hour at 850° C., cold rolled to 0.030 inch thickness annealed 1 hour at 850° C. and finally cold rolled to 0.011 inch finish thickness. Epstein samples from the 6-mil material were annealed 72 hours in dry hydrogen at 925° C. while the 11-mil materials were annealed for 48 hours at 900° C. Essentially complete secondary grain growth was obtained in all samples after these final anneals and reference to TABLE V summarizes the magnetic characteristics exhibited by the alloys.
TABLE V______________________________________ P.sub.c19Coil Final t H.sub.c B.sub.r B.sub.10 P.sub.c15 P.sub.c17 P.sub.c18 (W/No. (mils) (Oe) (kG) (kG) (W/lb) (W/lb) (W/lb) lb)______________________________________18 6 0.135 16.9 19.2 0.54 0.68 0.79 0.9318 11 0.122 16.1 18.8 0.70 0.93 -- --19 6 0.138 15.4 19.1 0.56 0.72 0.84 0.9920 6 0.145 15.7 18.6 0.57 0.77 0.91 1.0620 11 0.119 15.9 18.9 0.71 0.94 -- --21 6 0.137 15.9 18.7 0.54 0.71 0.84 0.97______________________________________
It should be noted that while the alloys containing chromium have a slightly lower B 10 value than similar alloys without chromium, the loss characteristics compare quite favorably and with the improved volume resistivity the materials become ideally suited for use as transformer core materials.
An important feature of mill processing conventional grain oriented 3% Si-Fe is the high slab temperature, 1300-1400° C., required for hot rolling to obtain the optimum texture. This high temperature hot rolling increases the final processing cost due to added energy requirements, oxidation losses, and equipment wear. It has been found according to the present invention that good textures can be obtained using slab temperatures as low as 1100 to 1200° C., as well as the conventional 1300° C. Low slab temperatures, such as 1100° and 1200° C., would result in cost savings and allow hot rolling to be done in mills that do not have special high temperature slab heating facilities.
Alloy A2 slabs 9024 and 9014, without chromium additions, were hot rolled in the mill at 1320° and 1160° C., respectively, to a hot band thickness of about 0.180 inches. The final hot band temperature of the slabs rolled at 1320° and 1160° C. were about 1020° and 880° C., respectively, and the coiling temperatures were about 720° and 630° C., respectively. After pickling, samples were rolled in the laboratory by a three stage cold rolling process to a final thickness of 6 or 11 mils using either box or strip intermediate anneals as delineated in Table VI. Alloy B was hot rolled in the mill at 1200° C. to a thickness of about 0.160 inches. This alloy was then cold rolled to final thicknesses of 6 and 11 mils using intermediate box anneals according to the following Table VI.
TABLE VI______________________________________COLD ROLLING AND ANNEALING SCHEDULES______________________________________Schedule I - Alloy A2 - Box Intermediate Annealed -6 Mil Final GaugeA. Box anneal in dry hydrogen at 850° C. for a time at temperature of about 5 hours. Rapidly cool by placing in a cooling chamber containing room temperature dry hydrogen.B. Cold roll from hot band gauge to about 0.080 inch.C. Same as A.D. Cold roll from 0.080 to about 0.020 inch.E. Same as A except soak time at 850° C. is one hour.F. Cold roll from 0.020 to about 0.006 inch.G. Programmed box anneal in dry hydrogen (Final Anneal). Heating and cooling rates of 50° C./hr with a 72 hour soak at 925° C.Schedule II - Alloy A2 - Strip Intermediate Anneal6 Mil Gauge Same as Schedule I above except that box anneal-ing steps A, C and E have been replaced by strip annealsin dry hydrogen at 825° C. for a time at temperature ofabout one minute, a heating rate of about 200° C./minute,and a cooling rate of about 80° C./minute.Schedule III - Alloy A2 and Alloy B - Box IntermediateAnnealed - 11 Mil GaugeH. Cold roll from hot band gauge to 0.080 inches.I. Box anneal at 850° C. in dry hydrogen for 1 hour at temperature.J. Cold roll from 0.080 to 0.030 inches.K. Repeat step I anneal.L. Cold roll to .011 inches.M. Programmed box anneal in dry hydrogen (final anneal). Heating and cooling rates of 50° C./hour with a 48 hour soak at 900° C.Schedule IV - Alloy B - Box Intermediate Anneal -6 Mil final Gauge Same as Schedule I except that final box annealperformed at 900° C. for 48 hours.______________________________________
Epstein samples having processing histories in accordance with the schedules shown in Table VI exhibited essentially complete secondary recrystallization structures with magnetic properties as shown in Table VII.
TABLE VII______________________________________ Hot Cold R Roll Sched- FinalAlloy/ Temp. ule Gauge H.sub.c B.sub.10 P.sub.c15 P.sub.c17Slab °C. No. (mils) (Oe) (kG) (W/lb) (W/lb)______________________________________A2/9024 1320 I 6 0.122 19.8 0.57 0.71A2/9024 1320 II 6 0.133 19.2 0.61 0.77A2/9024 1320 III 11 0.123 19.1 0.74 0.97A2/9014 1160 I 6 0.128 19.4 0.57 0.73A2/9014 1160 II 6 0.131 19.2 0.58 0.74A2/9014 1160 III 11 0.120 19.2 0.73 0.93B/705L 1200 IV 6 0.154 19.1 0.65 0.880031B/705L 1200 III 11 0.136 19.4 0.79 1.030031______________________________________
These results demonstrate that A2 alloys hot rolled at 1160° have very similar properties to those rolled at 1320° C.
In further examples of the present invention, alloy A2 slabs were hot rolled at 1100° or 1300° C. to 0.180 inches or 0.090 inches in thickness. An alloy B slab was hot rolled at about 1200° C. to a hot band thickness of 0.180 inches. The hot bands were then cold rolled to 6 or 11 mils by a two stage cold rolling process as shown in Table VIII.
TABLE VIII______________________________________TWO STAGE COLD ROLLING ANDANNEALING SCHEDULES______________________________________Schedule V 0.090" Rolled to 0.011" Final SizeN. Cold roll to 0.025 inches.O. Box anneal in dry hydrogen for one hour at 850° C. Rapidly cool by placing in a cooling chamber containing room temperature dry hydro- gen.P. Cold roll to 0.011 inches.Q. Programmed box anneal in dry hydrogen (final anneal). Heating and cooling rates of 50° C./hour with a 48 hour soak at 950° C.Schedule VI 0.090" Rolled to 0.006 Final Size Same as Schedule V with the exceptions that in thefirst cold rolling step the material is reduced to 0.020inches and in the second cold rolling step it is reducedto 0.006 inches. The final anneal is performed at 925° C.for 72 hours at temperature.Schedule VII 0.090" Rolled to 0.006 Final SizeR. Strip anneal in dry hydrogen at 825° C. for about one minute at temperature. Heating rate ˜200° C./ minute, cooling rate ˜80° C./minute.S. Cold roll to 0.020 inches.T. Repeat step R.U. Cold roll to 0.006 inches.V. Programmed final box anneal as in Schedule VI.Schedule VIII 0.180" or 0.160" Rolled to 0.011 Final SizeW. Cold roll to 0.080 inches.X. Box anneal per step O.Y. Cold roll to 0.011 inches.Z. Programmed box anneal as in previous schedules with exception that material is held at 900° C. for 48 hours.______________________________________
Alloy A2 and B material were processed into Epstein samples using the processes described in Table VIII. Those Epstein samples exhibited complete secondary recrystallization and the magnetic properties shown in Table IX.
TABLE IX__________________________________________________________________________ Hot Roll Cold R. Final Temp. Hot Band Sched- Gauge H.sub.c B.sub.10 P.sub.c15 P.sub.c17Alloy (° C.) t (mils) ule No. (mils) (Oe) (kG) (W/lb) (W/lb)__________________________________________________________________________A2 1300 90 V 11 0.114 19.2 0.71 0.91A2 1300 90 VI 6 0.114 19.8 0.60 0.74A2 1300 90 VII 6 0.118 19.6 0.61 0.76A2 1300 180 VIII 11 0.124 19.0 0.73 0.97A2 1100 180 VIII 11 0.141 19.1 0.72 0.94B 1200 160 VIII 11 0.125 19.3 0.77 0.99__________________________________________________________________________
Generally the textures and magnetic properties are equivalent to those obtained by the three stage cold rolling process according to the present invention.
It thus becomes apparent that the alloy of the present invention will demonstrate a high degree of (110) [001] orientation and a secondary recrystallized microstructure despite the fact that the material may have an open γ loop and the employment of significantly lower temperatures for the final annealing treatment. A radical departure has been demonstrated from the heretofore commercial processing of similar materials. Moreover, the process is applicable for both light gauge (0.006") as well as heavy gauge (0.012") materials although at the higher silicon contents, heavy gauges are preferred.
In addition to the preceding alloys studied, two 7000 gm (1"×5"×about 7") laboratory ingots were cast. These ingots contained 3% Si, 0.1% Mn, 0.008% S, 0.015% C, 0.012% Al, 0.012% N. In addition, one ingot contained 1.0% Cr. Sections of these ingots were hot rolled at 900° or 1200° C. to 0.180 inches, pickled, and then cold rolled in a three-stage cold rolling process to a nominal 0.012 final gauge size. Intermediate strip anneals at 850° C. in dry hydrogen were performed between cold rolling stages. The material was then given a final strip anneal at 815° C., coated with MgO+5% MgSO 4 , followed by a final alpha phase anneal at 1175° C. for 24 hours in dry hydrogen. These materials exhibited substantial secondary recrystallization and a predominantly (110)[001] texture. Coated samples from the alloy without Cr additions and hot rolled at 1200° C. exhibited the following magnetic properties: B 10 =17.7 kG, P c15 =0.58 W/lb at 60 Hz, and P c17 =0.85 W/lb at 60 Hz.
Although the invention has been shown in connection with certain specific embodiments, it will be readily apparent to those skilled in the art that various changes in the method steps and compositional limits can be made to suit requirements without departing from the spirit and scope of the invention. | An alloy and a method of making the same are described. This alloy is suitable for use in an electrical magnetic induction apparatus. The alloy is characterized in that it may undergo an α⃡γ phase transformation upon heating to a sufficiently high temperature and in which the microstructure is oriented in the (110)[001] manner as described by Miller indices and is further characterized by a secondary recrystallized microstructure. The specification is replete with magnetic induction data as well as core loss data for alloys falling within the scope of the invention. | 2 |
FIELD OF THE INVENTION
This invention relates generally to a low cost means of adding value to portable media such as “smart cards” of microprocessor or encrypted memory types, key fobs, magnetic stripe cards or any other form factor that permits electronic read/write functions that can be used to replace coins in exact change payments of small amounts spent by a consumer.
BACKGROUND OF THE INVENTION
Traditionally, exact change micropayment transactions such as vending machines, pay-for-use laundry machines, pay telephones and public transit access were facilitated through the use of coins. A user would obtain a sufficient number of coins or tokens of the correct denomination to obtain the desired product or service. Bill changers were sometimes provided but are expensive to install and maintain, and are prone to burglary with the result that coins are not generally available to the public at the place where the exact change micropayment transaction is to take place.
In recent years alternatives to coins for micropayments have been developed to reduce the nuisance of carrying or searching for exact change. These alternative payment forms have typically been such media as disposable smart cards or magnetic swipe cards. These media typically have a preloaded value when purchased from a vendor. There are major disadvantages with these micropayment media. The first disadvantage with these micropayment reload devices is to the user. With prepaid/preloaded cards, the user must purchase cards in fixed cash increments creating the problem of having residual non-useable value left on the media, depending on the vend rate for the desired product or service. The media is disposable which adds cost to the issuer. There are also additional costs associated with distribution, most notably, payments to retail vendors for distributing such media and security issues with cards that have preloaded value.
Reloadable microchip media such as smart cards and key fobs, and encrypted magnetic media such as swipe cards have the potential of overcoming all of these problems with a number of additional benefits including the ability to load non-preset or fixed amounts, facilitating a low cost means of granting repayments of error amounts or lost amounts thereby saving the costs of mailing small refund cheques and placing additional applications such as loyalty programs on the media.
Historically the replacement of coins by reloadable smart cards and other electronic micropayment media has been prohibitively expensive due to the high cost of reload devices such as currency acceptors to media and credit/debit card acceptors to media. The high cost of such reload devices has limited their availability resulting in a lack of infrastructure to support the widespread adoption of reloadable micropayment media.
Currency acceptors are high cost, armoured, mechanical reload devices prone to breakage and counterfeit money and carry substantial risks of burglary and vandalism. They must be placed in high security locations and the funds accumulated in the boxes need to be collected, counted and presented to banks in a secure environment at considerable cost.
Debit/credit card reload devices while lower in cost than currency acceptors initially carry the ongoing costs of networking to telephone or other remote communications systems in order to validate the financial transactions. In addition, these are not usable by people who have neither credit nor debit account facilities or balances with financial institutions.
Realizing these disadvantages in the deployment of reloadable micropayment reload devices the present invention provides such loading services in a completely offline environment thus reducing the capital necessary to deploy reload devices in adequate numbers to convenience the user. In addition to the added convenience the user will also have the ability to load non-fixed amounts if so desired. Such a reload device has the added benefit of enabling the issuing organization to grant refunds to their media using customers, saving the additional costs of mailing refund cheques to users who have substantiated refund claims further adding convenience to customers.
SUMMARY OF THE INVENTION
A method for a value supplier to transfer value to an electronic purse possessed by a holder without requiring direct electronic communication between said value supplier and said medium, said method comprising the steps of:
(i) providing a portable storage medium to said holder having a Card Identification Code (“CIC”), a machine readable and reconfigurable Transaction Sequence Number (“TSN”) storage area and at least one said purse wherein each said purse is a machine readable and reconfigurable storage means and has a unique purse address; (ii) recording said TSN against said CIC in a reconfigurable data storage and retrieval system; (iii) receiving a request from said holder including said CIC, a desired value and payment instructions; (iv) determining said TSN stored in said data storage and retrieval system against the CIC presented in step (iii); (v) using an encryption algorithm to generate a unique One Time Number (“OTN”) based on said CIC, said TSN, said purse address and said desired value; (vi) presenting said OTN to said user; (vii) reconfiguring said TSN in said storage and retrieval system to vary said TSN by a predetermined increment; (viii) providing a reload device having a reader for reading said TSN and CIC from said portable storage medium, CIC input means for receiving said CIC on said storage medium, OTN input means for receiving said OTN from said holder, a decrypter having a decryption algorithm corresponding to said encryption algorithm in step (v) for decrypting said OTN, a verifier for verifying that said CIC and TSN on said storage medium match said OTN input by said holder and a loader for loading value into said purse corresponding to said desired value; (ix) receiving said storage medium in said reloader; (x) determining said CIC and said TSN on said storage medium and receiving said desired value and said OTN; (xi) decrypting said OTN using said decryption algorithm; (xii) verifying whether said CIC and TSN components of said OTN conform to said CIC and said TSN on said storage medium; (xiii) if said verifying in step (xii) determines conformance, loading said desired value into the purse identified by said purse address and incrementally adjusting said TSN on said storage medium by said predetermined increment in step (vii); and, (xiv) if said verification in step (xii) fails to determine conformance, causing said reloader to display an error message.
The method may include the further steps of:
(xv) configuring said reload device to monitor a predetermined number of retries of steps (ix) through (xii) for a given of said storage medium and, should said predetermined number of retries fail to yield a determination of said conformance, to enter a “disabled” indicator on said storage medium; and, (xvi) further configuring said reload device to check for said disabled indicator and if detected, cease carrying on with the transaction steps and to display an error message to said holder.
The payment instructions received in step (iii) may include payment issuer information and may be confirmed with the issuer prior to continuing. Should payment be refused by the payment issuer the cardholder may be notified accordingly.
A reload device is provided for a portable value storage medium (“medium”). The reload device has a medium reader for reading a stored transaction sequence number (“TSN”) stored on the medium, a CIC input means for receiving a presented Card Identifier Code (“CIC”) and an OTN input means for receiving an One Time Number (“OTN”) containing encrypted TSN, CIC and value components and purse address. The reload device further has a decoder for decoding the OTN to determine the encrypted TSN, CIC and value components. The reload device also has a comparator communicating with the medium reader, CIC input means, OTN input means and decoder for comparing at least the encrypted TSN and CIC with the stored TSN and presented CIC. A loader communicates with the comparator for loading value onto the medium corresponding to the value. The comparator is configured to only load the value if the encrypted TSN and CIC components accord with the stored TSN and presented CIC. The reload device also has a TSN updater for updating the stored TSN to a next sequential TSN.
The reload device may have a security means associated with the reloader and the comparator. The security means may disable the medium upon detecting a predetermined number of unsuccessful OTN inputs against a particular CIC, causing an error message to be presented to a holder of the medium seeking to add value thereto.
A security means may, after the unsuccessful OTN inputs place a restriction on the card against further use. The medium reader may read any such restriction and notify the comparator to disable the storage medium without requiring any further unsuccessful attempts.
An OTN generator is provided for generating a One Time Number (“OTN”) for subsequent offline use with any of the issuing organization's loaders for loading a predetermined value onto a storage medium having a Card Identifier Code (“CIC”) and a reconfigurable stored Transaction Sequence Number (“TSN”). The OTN generator has a database for storage and retrieval of information on account status, CIC's for issued cards and the current TSN associated with each CIC. The OTN generator further has a system processor communicating with the database and access means associated with the processor for oral or written communication between a holder of the medium and the OTN generator. The OTN generator further has input means associated with the access means for receiving the CIC, a desired amount and type of value to be processed and a purse address. Debit means may be associated with a system processor for debiting the source of funds by an amount corresponding to the desired amount of value. Verification means may be associated with a system processor for determining whether the source of funds identified by the holder of the medium is in good standing. An encrypter may be associated with the system processor for generating the OTN according to an encryption algorithm based on at least the CIC, the TSN, the desired value and purse address. The processor may be configured to provide an error message if the account is not in good standing. The processor may be configured to signal the encryptor to generate a valid OTN and to communicate the valid OTN to the holder. The holder is thus able to input the OTN into the reloader for decryption and for the reloader to write a value onto the medium. The processor may further be configured to update the database to adjust the TSN associated with the CIC by a predetermined increment after generating a valid OTN.
The access means of the OTN generator may communicate over at least one of a computer and a telephone network. The input means of the OTN generator may be a telephone handset or a computer keyboard. The OTN generator output may be electronic via speech generator or written to a display screen or a document generator.
DESCRIPTION OF DRAWINGS
Preferred embodiments of the present invention are described below with reference to the accompanying illustrations in which:
FIG. 1 is a pictorial representation of a storage medium according to the present invention;
FIG. 2 is a perspective view illustrating a reload device according to the present invention;
FIG. 3 is a device functional block diagram of the reload device;
FIG. 4 is a device level transaction flow chart for the reload device;
FIGS. 5 and 6 are a flow chart in two parts illustrating a device level transaction flow algorithm in accordance with the present invention;
FIG. 7 is a flow chart illustrating a manner according to the present invention that an OTN may be provided to a holder;
FIG. 8 is a flow chart illustrating an alternative embodiment of a way that an OTN may be provided to a holder;
FIG. 9 is a block diagram illustrating OTN encryption elements;
FIG. 10 is a schematic illustration of an OTN generator in accordance with the present invention; and,
FIG. 11 is a flow chart illustrating a possible sequence of steps for resychronizing a TSN according to the present invention.
DESCRIPTION OF PREFERRED EMBODIMENTS
A storage medium according to the present invention is generally indicated by reference 20 in FIG. 1 . The storage medium 20 may be a magnetic stripe card although other configurations, such as a microchip contained in a card, a key fob or other physical carrier may be utilized.
The storage medium 20 has a card identification code 22 (“CIC 22 ”) unique to that storage medium 20 .
The CIC 22 would generally be user readable as the users would be required to recite it as part of the transaction described below.
The storage medium 20 has an area 24 which is machine readable and reconfigurable on which is stored a Transaction Sequence Number (“TSN”). The storage medium further has at least one area referred to as a “purse” 26 which is a reconfigurable storage means to which value may be added and from which value may be removed. The purse 26 may be part of the area 24 or an adjunct thereto. Each purse 26 would have a unique address associated with it. The address would have to be accessed to load each purse 26 .
In use, the storage medium 20 may be issued to a holder (reference 208 in FIG. 10 ) by a value supplier. The holder 208 can then contact the value supplier and, as discussed in more detail below, arrange to have value added to the purse 26 . The value is added using a reload device 50 in FIG. 2 . The reload device and the value supplier in effect communicate via an encrypted code (i.e. the One Time Number (“OTN”)) using the holder 208 as an intermediary rather than through direct electronic communication.
The storage medium 20 , once loaded, may be utilized to transfer at least a portion of the value to a storage medium reader such as a vending machine, a washing or drying machine, a telephone, a transit system or other users where preferably cashless small transactions are required. As different users may have different purse requirements, more than one purse 26 , each satisfying different user requirements, may be provided. For example a transit pass may be configured in terms of “passes” with one pass required per ride rather than having a monetary value which is debited by a medium reader. The expression “value” should therefore be broadly interpreted to include other than actual cash values loaded.
FIG. 2 is a pictorial representation illustrating a reload device 50 according to the present invention. FIG. 3 is a device functional block diagram of the reload device 50 .
The reload device 50 includes a medium reader 52 for reading information stored on the storage medium 20 , in particular the TSN on the area 24 and preferably also the purse 26 .
The reload device 50 further has a CIC input means such as the keypad 54 for receiving the CIC 22 . While a keypad 54 is illustrated, alternative means may be utilized. For example the CIC may be both printed on the card and stored on the card in machine readable form in which case the medium reader 52 may also be configured to act as the CIC input means.
The reload device 50 has an OTN input means for receiving the OTN. The OTN input means may be the keypad 54 . The OTN is an encrypted code based on the TSN, the CIC and value components. The OTN may also contain a purse identifier component such as a purse address. The OTN is in effect the message carried by the holder of the storage medium from the value supplier to the reload device 50 which enables verification of the storage medium 20 and loading of value into the purse 26 .
As the OTN is an encrypted message to the reload device 50 , the reload device 50 includes a decoder 55 which may be a reload processor 56 communicating with a first security module 58 which runs a decryption algorithm. The decoder 55 receives the OTN and determines the TSN, CIC and value components.
The reload device 50 also has a comparator for comparing the CIC and TSN input or read from the storage means 20 with the TSN and CIC determined by the decoder 55 . This may for example be accomplished by suitably configuring the reload processor 56 and having it communicate with the keypad 54 , medium reader 52 and first security module 58 . “Suitably configuring” refers to providing appropriate hardware and software either as part of or in communication with the reload processor 56 .
The comparator determines whether the information contained in the OTN accords with the TSN and CIC on the storage medium 20 . If it does, then the comparator instructs, such as through the reload processor 56 , a loader 60 to add the value to the appropriate purse 26 . If it doesn't then the comparator may simply refuse to instruct the loader 60 but more preferably will arrange for an error message to be presented to the holder of the storage means 20 . This may be accomplished by communicating the non-accord condition to the reload processor 56 which in turn instructs a display 64 also in communication therewith to display the error message.
The reload device 50 is also provided with a TSN updater for updating the TSN after each successful transaction. This may form part of the loader 60 . The TSN is updated for example by a predetermined increment or to a next predetermined sequential value after each successful transaction. This prevents the storage medium 20 from being loaded again using the same OTN. The reason it can't be loaded again is that the updated TSN will not accord with the encrypted TSN resulting in a non-accord determination by the comparator.
The reload device 50 may incorporate further security features for example a second security module 62 may communicate with the reload processor 56 to provide access codes enabling the reload processor 56 to communicate with the medium reader 52 , keypad 54 and possibly also the first security module 58 .
Additionally, the reload 50 processor 56 may be configured to monitor subsequent unsuccessful attempts to load value such as may be the case if someone is attempting to guess an OTN. The area 24 or any other area of the storage medium 20 which is machine readable may then be loaded with a “security lock-out” notation which can be detected by the medium reader 52 and communicated to the reload processor 56 . The reload processor may be further configured to disable the storage medium 20 and cause the display 64 to present a suitable error message. The restriction on reloading may be time limited.
Alternatively, once a security lock-out notation is placed on the storage medium 20 , the system can be configured to require entry of a one time “release” code to be provided by the value supplier in order to remove the security lock.
On occasion it may be necessary to resynchronize the TSN on the storage medium 20 . This might for example occur as a result of a system malfunction. Accordingly the reload processor 56 , decoder 55 and loader 60 may be configured to allow the keypad to present a coded TSN to the reload processor 56 for decoding by the decoder 55 and loading onto the storage medium 20 in lieu of any previously loaded TSN.
FIG. 4 is a device level transaction flowchart 100 for the reload device 50 illustrating user interaction with the device. Box 102 corresponds to the user inserting the storage medium 20 into the medium reader 52 and the medium reader 52 reading the storage medium 20 . Box 104 depicts the display 64 showing the balance on the card. Alternatively the display 64 could prompt for the OTN and also the CIC if the CIC isn't read by the medium reader 52 . Box 106 represents the user entering the OTN on the keypad 54 .
The reload device 50 next performs a validation algorithm at box 108 which is performed by the comparator. Should the validation result in failure as depicted by box 110 , an error message is displayed as depicted by box 112 . Should the validation prove successful, the display 64 may be instructed to display an approved load value as depicted by box 114 .
The reload processor 56 may also be configured to determine whether the approved reload amount will exceed a predetermined maximum balance in the selected purse 26 . This is depicted by box 116 . Should this occur, the display 64 may be caused to present such a message as depicted by box 110 and further prompt the holder to remove the storage medium 20 from the reload device 50 , as depicted by box 112 .
Should the selected purse 26 be capable of accepting the approved load value the reload processor 56 may instruct the display 64 to display the current balance (box 120 ) and instruct the loader 60 to load the approved value into the selected purse 26 as depicted by box 122 . The reload processor 56 may then calculate and cause the display 64 to present first the new balance (box 124 ) and finally cause the display 64 to display a message, such as at box 126 , informing the holder that the transaction is complete and prompting the holder to remove the storage means 20 from the reload device 50 .
FIGS. 5 and 6 are a flow chart in two parts illustrating a device level transaction flow algorithm 150 in accordance with the present invention.
At reference 152 the storage medium 20 is presented to the medium reader 52 . At reference 154 the display 64 shows any remaining balance on the card. The reload device next, at reference 156 , determines if any security lock-out is active on the card. If a security lock-out is active, then, at reference 158 the reload device 50 , typically through its reload processor 56 determines if the security lock-out has expired. If it has expired, then at reference 160 , it is erased, If it hasn't expired, then at reference 162 the display 64 is operated to present an appropriate message. This assumes that a time sensitive security lock-out is being used, which may not be the case. The system may be configured to require that a one time code be obtained from the value supplier in order to remove the security lock-out.
If a security lock-out is either not present or has expired the reload device 50 accepts a user entered OTN at reference 164 . The reload processor 56 extracts the TSN from the OTN at reference 166 . The comparator at 168 compares the decrypted TSN with the TSN read off of the storage medium 20 by the medium reader 52 . A failed match causes the display 64 to present an appropriate message at reference 170 . Next at reference 172 , the reload processor 56 determines whether a predetermined sequential retry threshold has been achieved. If not the storage medium may be reinserted at 152 . If it has been achieved then a security lock-out, which may be time sensitive, is placed on the storage medium 20 at reference 174 , at least temporarily disabling the storage medium 20 from operating the reload device 50 .
It will be appreciated that presence of a security lock-out disables the storage means 20 from being used with any reload device 50 . This is because the security lock-out is carried by the storage means 20 rather than by the reload device 50 .
If no security lock-out is currently active and the decrypted TSN matches the stored TSN, full decryption begins at referenced 176 . At reference 178 the comparator checks for a match between the CIC on the storage medium 20 and the CIC decrypted from the OTN. A failed match causes a return to step 170 . A successful match at reference 180 may result in the reload processor 56 determining which purse 26 to load if more than one purse 26 is available. This can be part of the information encrypted in the OTN. Next, at reference 184 , the reload processor 56 determines whether adding the approved value will exceed a maximum balance. If yes, then the display is operated to present a suitable message at reference 186 which may also prompt the holder to remove the storage medium 20 from the reload device 56 .
Should the approved load value not exceed the maximum card balance, the value is added and the TSN sequentially adjusted. Either may follow the other. According to the FIG. 6 embodiment the TSN is incremented at reference 188 and the value loaded to the purse 26 by the loader 60 at reference 190 . Appropriate accompanying messages may also be displayed. For example at reference 192 the current balance and amount being loaded may be displayed. Next at reference 194 the new balance may be displayed. Generally at reference 196 the holder is instructed to remove the card and the reload transaction is completed at reference 198 .
FIGS. 7 and 8 are flow charts illustrative of two ways that an OTN may be provided to the holder. FIG. 9 illustrates the OTN encryption elements. FIG. 10 is a schematic illustration of an OTN generator 200 in accordance with the present invention.
The OTN generator 200 has a database means 202 for storage and retrieval of information on account status associated with each storage medium 20 that has been issued and may include information on account status of the holder 208 as well as any other relevant account. The database 202 may further provide for storage and retrieval of CIC's for issued storage medium 20 and current TSN's associated with each CIC.
The OTN generator 200 has a system processor 204 which communicates with the database 202 . Access means 206 are associated with the system processor to enable communication between a holder 208 of the storage medium 20 and the system processor 204 . The access means 206 has input means 210 which may be fully automated for example relying on a computer hook-up over the Internet or utilizing touch tone features of a telephone handset. Alternatively (or additionally) the access means 206 may have input means 210 which uses human intervention such as a call centre wherein the call recipient has keyboard access to the system processor.
The input means 210 may prompt for and receive the CIC and a desired amount of value from the holder 208 . As well the input means 210 may prompt for and receive a source of funds 212 selected by the holder 208 from where the value is to be obtained. The source of funds may for example be a credit facility or a bank account held by the holder 208 . The credit facility may be a credit card company or the value supplier that controls the OTN generator 200 .
Account verification means 214 may be associated with system processor 204 for determining whether the selected source of funds is in good standing. The account verification means may in turn communicate with the source of funds 212 or with the database 202 depending on whether current or historical data is to be verified.
Debit means 216 are associated with the system processor 204 for enabling the system processor 204 to debit the source of funds 212 by an amount corresponding to the desired value and possibly also a service or transaction charge.
An encrypter 218 is associated with the system processor 204 for generating the OTN according to an encryption algorithm. As discussed above, the encryption algorithm would typically be based on at the CIC, TSN and the desired amount of value. The encryption algorithm may also take into account which purse 26 is selected if more than one is available.
The system processor 204 may be configured to signal the encrypter to generate an OTN which will cause the reload device 50 to generate an error message if the account is not in good standing. Alternately the OTN may communicate an appropriate message to the holder 208 through the access means 206 should this be the case.
The system processor 204 may be further configured to signal the encrypter to generate a valid OTN and to communicate the OTN to the holder through the access means 206 . Output means 220 may be provided in communication with the system processor 204 to link the system processor 204 with the access means 206 . The input means 210 and output means 220 may be incorporated in a common element of the OTN generator 200 .
The system processor 204 is further configured to update the database to adjust the TSN associated with the CIC of the storage medium 20 to be loaded by a predetermined increment. The predetermined increment will be the same for the OTN generator 200 as for the reload device 50 .
FIG. 7 illustrates how an OTN may be generated with the OTN generator 200 in an automated telephone system configuration. At reference 300 the holder 208 calls an automated telephone number. The holder 208 may be prompted to and may choose a language preference at reference 302 . At reference 304 the holder 208 is prompted for and enters, using a telephone keypad, the CIC number. The holder 208 is then prompted for and enters a credit card number and expiry date at reference 306 . At reference 308 the holder 208 is prompted for and enters a desired load amount, and, if applicable, a selected purse 26 .
The system processor 204 verifies the availability of funds at reference 310 through the account verification means 214 . Should the verification fail, as indicated at reference 312 , the transaction is cancelled as indicated by reference 314 .
Should the verification be successfully approved, the system processor 204 , using the encrypter 218 , generates an OTN at reference 316 . The system processor further increments the TSN in the database 202 at 318 and provides the OTN to the holder at reference 320 .
It will be appreciated that the above sequence may be varied to some extent. For example the load amount and purse may be entered before the credit card information. Also the TSN may be incremented after the OTN is provided to the card holder 208 .
FIG. 8 is a flow chart illustrating the generation of an OTN using a call centre as the access means 206 . The holder 208 phones the call centre at reference 350 and provides, possibly upon prompting, the CIC at reference 352 . The holder 208 is further prompted for and provides a credit card number and expiry date at reference 354 and a desired load amount and purse 26 at reference 356 . The holder 208 would supply the foregoing information to a call centre operator who has input means 210 for inputting the information into the system processor 204 .
The system processor 204 may verify the transaction with the source of funds 212 at reference 358 . Although it is expected that in most cases the system processor 204 would be a computer, it may be possible to use a human operator as the system processor 204 as long as access is provided to the peripheral components of the OTN generator 200 which communicate with the system processor 204 .
Should verification result in a denial, as shown at reference 360 , the transaction is cancelled at reference 362 and the holder 208 may be informed accordingly.
Should verification prove successful and result in acceptance, the call centre at reference 364 enters the data into the system processor which at reference 366 runs the encrypter 218 to calculate the OTN. This may further require accessing the database 202 to obtain the current TSN. The call centre provides the OTN to the holder 208 at reference 370 , the TSN is incremented in the database 202 at reference 368 and the transaction is complete.
FIG. 9 is a schematic diagram illustrating one manner in which an OTN may be encrypted. Two encryptions are illustrated. In a first encryption 400 , elements of the CIC, approved load amount and desired purse are loaded at references 402 , 404 and 406 respectively. The first encryption yields a first result 408 . A second encryption occurs at reference 410 and is based on the TSN which is loaded at 412 . The second encryption encrypts the TSN to yield encrypted TSN 414 . The encrypted TSN 414 is combined with the first result 408 to yield a resultant OTN 416 which is the OTN provided to the holder 208 .
FIG. 11 is a flow chart illustrating a possible sequence of steps for resychronizing a TSN when a load attempt fails. At reference 500 , the holder 208 calls a call centre to report a failed attempt. The call centre obtains the CIC and at reference 502 determines the TSN. The TSN may be encrypted at reference 504 for example using the encrypter 218 and the encrypted TSN is provided to the holder 208 at reference 506 . The user records the encrypted TSN at reference 508 and the call centre may, at reference 510 synchronize the database with the new TSN.
Reload devices 50 of the above type may be owned by different issuing organizations, each of which will have their own OTN generator 200 . Should this be the case, provision will be required to separate one organization's storage media 20 and reload devices 50 from those of another. This may be accomplished for example by having an organization identifier as part of the purse address.
The above description is intended in an illustrative rather than a restrictive sense. Variations may be apparent to those skilled in the art without departing from the spirit and scope of the invention as defined by the claims set out below. For example it may not be necessary to follow the exact sequence of steps described or to use the exact encryption methodology. Variations to these and other aspects will no doubt be apparent to those skilled in the relevant arts. | An offline code-based reload device and method for adding value to a reconfigurable memory storage means in a portable storage medium. Reload is effected using a reload device not directly connected by telephone or any other communication network to a value supplier. The system uses a “one time use number” (“OTN”) generated by a computer program containing an algorithm containing information on the value to be added and a transaction sequence number (“TSN”). Upon presentation of the portable storage medium to the reload device and entry of the OTN into a numeric keypad, the reload device decodes or disassembles the OTN to verify its authenticity, validate that it was created for the specific portable storage medium presented to the reload device and to verify through the TSN that the OTN has not been previously used to add value from the receiving reload device or any other reload device. The reload device further extracts the value from the OTN, adds the value to a selected purse on the portable storage medium and loads a new TSN to the portable storage medium. | 6 |
[0001] This is a continuation of application Ser. No. 11/600,941, filed Nov. 17, 2006, which was a continuing application of application Ser. No. 10/702,313, filed Nov. 6, 2003, now U.S. Pat. No. 7,226,959.
FIELD OF THE INVENTION
[0002] This invention relates to the synthesis and use of water soluble energy curable stereo crosslinkable ionomers used in the manufacture of coated and printed materials.
BACKGROUND OF THE INVENTION
[0003] Ionomers are polymeric compounds carrying electronic charges within the polymer chain. Ionomers build outstanding properties like hardness and solvent resistance when two or more such polymeric chains create a ladder-type structure by salt formation. The ionic complexation of identical (e.g., bridged by a higher-valent counterion) or opposing charges (e.g., acid/base neutralization of amine-functional with carboxyl-functional polymeric species) on the polymer chains results in additional crosslinks, the number per unit volume of which determines the mechanical strength of the resulting solid. The more commonly used ionic complexation route typically proceeds through use of a more stable complex of the bridging counterion with a volatile material (e.g. ammonia) to allow blending in the liquid state followed by later crosslinking upon drying to a solid. The acid/base neutralization of two oppositely charged ionomers to create crosslinking, in contrast, is largely impractical due to the impossibility of blending these materials to generate anything other than an intractable crosslinked solid.
DESCRIPTION OF RELATED ART
[0004] The photopolymerization approach to ionomer crosslinking is not novel. U.S. Pat. Nos. 6,281,271 and 6,017,982 disclose the energy curing of ethylenically unsaturated ions to build covalent molecular weight in-situ and to trigger crosslinking via ionic complexation of identical charges on two or more ionomer chains, in the presence of water and a divalent metaloxide. U.S. Pat. No. 6,180,040 teaches the formation of an ionomer via photopolymerization using energy curable compositions of ionic monomers such as metal acrylic carboxylates copolymerized with polybutadiene resins. These compounds form ionomers upon polymerization and are bridged over a metal complex in a second (vulcanization) step. In neither of these examples is the bridging ion an organic polymer, either preexisting or formed by in-situ polymerization. Fundamentally, the ionic complexation routes illustrated in the above references yield materials with regular, repeating crosslink patterns and compact ionic structures.
[0005] Ionomers that crosslink only over ethylenically unsaturated moieties (i.e., do not employ either bridging ions or acid/base combinations of separate, oppositely charged ionomers or monomers) are commonly used in coatings and photoresists. These compounds are usually water soluble polymers carrying ethylenically unsaturated groups in or grafted onto the polymer chain of the single-chain ionomer. Examples of these polymer types are neutralized acrylics described in U.S. Pat. No. 4,275,142; styrene-maleic anhydride described in U.S. Pat. Nos. 3,825,430 and 4,401,793; and polyester, or urethane polymer salts described in U.S. Pat. Nos. 6,207,346 and 5,554,712. Since no use is made of the ionic groups to create additional crosslinks, cured films made from these ionomers are often structurally weakened by the existence of ionic charges, as these sites retain moisture, which plasticizes the cured final polymer (e.g., they show lower rub resistance to water compared to uncharged polymers).
[0006] U.S. Pat. Nos. 4,745,138; 5,868,605 and 6,099,415 disclose the use of chemically similar but non-neutralized resins in energy curing compositions. However, these patents do not teach the formation of blends with resins, oligomers, or monomers that could potentially neutralize an energy curable resin in a way that might crosslink the polymer. In addition, the viscosity of these non-neutralized resins is typically high. To bring them to application viscosity they must be diluted with either a large amount of a low viscosity reactive monomer or with a solvent.
SUMMARY OF THE INVENTION
[0007] The invention is the formation and use of water soluble energy curable ionomers that form a stereo crosslinked network upon curing over ethylenically unsaturated and polyionic sites. As a result, energy curable stereo-crosslinkable ionomers are produced that deliver a low viscosity liquid and create a cured solid film having superior mechanical and solvent resistance properties along with good adhesion to difficult substrates. The materials also resist cracking and flaking, and offer improve gloss and rub resistance, and enhanced coverage when compared to existing materials used in formulating paints, inks, and coatings.
DETAILED DESCRIPTION
[0008] The present invention shows how in-situ photopolymerization can be used to generate the opposing charge type of polymer from low-viscosity liquid monomer/oligomer blends that have utility in the manufacture of coated and printed materials. The structures formed in the present invention are random, largely amorphous, three-dimensional networks of opposing charge polymers with control over the rigidity of the crosslink. The invention employs lower molecular weight oligomeric resins and water as solvent to reduce viscosity and accelerate cure at zero volatile organic content (VOC). Cure occurs in the presence of the water, and the dissolved water is allowed to concurrently dry without application of additional energy to give cured structures that are surprisingly not sensitive to water. The oligomeric resins are neutralized with ethylenically unsaturated polyamines to form water-soluble resin salts. In some instances these salts are liquids (low melting solids), but more generally they require a water content above 10% to be fluid. In most instances, in order to provide useful viscosity, the water content will be above 30%.
[0009] In water based energy curable compositions, viscosity reducing monomeric compounds, typically employed in energy curable compositions are replaced with water. There are two fundamentally different technologies used in this field. One derives from ethylenically unsaturated water based emulsions, which are dried before curing. The other is based on partially soluble energy curable material where the curing reaction is carried out in solution and does not necessarily include a drying step before cure. The precursors employed in the present invention are water soluble at least partially water-soluble, a state that is obtained from the use of truly water soluble monomers and oligomers in admixture with the required ionic materials.
Ethylenically Unsaturated Resin
[0010] The water soluble ethylenically unsaturated oligomeric or polymeric resin may have acid functional groups (e.g. carboxylic acid groups) which are partially or totally neutralized with a base (e.g., an amine) to form a water soluble resin salt. Alternatively, the resin may have basic functional groups (e.g. amino groups) which are partially or totally neutralized with an acid (e.g. a carboxylic acid) to form a water soluble resin salt. A preferred embodiment is a neutralization product, where a water soluble, acrylated, resin salt is formed from an ethylenically unsaturated energy curable resin containing acrylic groups, methacrylic groups or a combination thereof; and carboxylic acid functional groups, neutralized by a base. While a more preferred resin salt product is a neutralization product prepared from an ethylenically unsaturated amine and a polyanionic resin. Suitable examples of a polyanionic resin are polyacrylic or styrene-maleic anhydride copolymers, containing carboxyl groups, and having an acid value of at least 80 (mg KOH per 100 g polymer). Commercially available examples of such resin are Carboset GA-1167 from BF Goodrich; Joncryl 690 from SC Johnson; and SMA 1000 from ELF Atochem. It is preferred that the polyanionic resin be partially esterified via a polymer analog reaction to tailor the final properties of the compound and the final product of compositions containing the compound (propanol, isopropanol, stearic alcohol, polypropylene glycol) but that such resin have the same acid number of 80. A preferred modification uses an ethylenically unsaturated alcohol to form an ethylenically unsaturated polyanionic resin containing at least two such functions per molecule. The resin is then neutralized to a pH of at least 5.5 with an ethylenically unsaturated amine or a mixture such amine and ammonia or other caustic component. If there is no ethylenically unsaturated content in the polyanionic resin, then the tertiary amine should be ethylenically unsaturated. If the polyanionic resin is ethylenically unsaturated, then the tertiary amine may be saturated provided that it contains at least two amine groups per molecule. However, it is most preferred that both components of the resin be ethylenically unsaturated.
[0011] A particularly preferred energy curable resin is a styrene/maleic anhydride copolymer partially esterified with a hydroxy alkyl acrylate or methacrylate. The hydroxy alkyl acrylate or methacrylate preferably of such resin is preferably hydroxy butyl acrylate or methacrylate. A partially esterified styrene/maleic anhydride copolymer may be neutralized without further modification or it may be further partially esterified with an alkanol such as butanol, propanol, ethanol and the like.
[0012] The acidic or carboxylic acid (anhydride) groups of the energy curable resin are partially or totally neutralized to provide a resin having the desired range of water solubility while retaining complete miscibility with other water soluble resins.
[0013] The resins used to form the compositions of the present invention while having an acid number of at least 80 have a molecular weight between 1,000 and 25,000; and more preferably between 1,000 and 10,000; and most preferably between 1,000 and 5,000.
Neutralization Agent
[0014] Any basic compound (e.g., alkali metal hydroxides such as calcium hydroxide, potassium, hydroxide and sodium hydroxide, ammonia, amines, etc.) may be used to neutralize the acidic groups of the resin. Preferred are ammonia, amines or combinations thereof. Even more preferred is amines, while more particularly preferred is an ethylenically unsaturated tertiary amine. By employing ethylenically unsaturated tertiary amines as the neutralizing agent, the acidic groups on the energy curable resin are totally neutralized to form a water soluble resin having additional polymerizable ethylenic groups. The use of ethylenically unsaturated tertiary amines as the neutralizing agent further allows the acid groups on the resin to be totally neutralized which aids in the formation of the stereo cross-linkable water soluble ionomers of the present invention.
[0015] The ethylenically unsaturated tertiary amine neutralizing agent of the present invention has the formula:
[0000]
[0016] wherein R′ is a short chain hydrocarbon group; R″ is H or a methyl group; and R′″ is selected from the group consisting of C 1 -C 20 alkylene, C 1 -C 20 aralkylene, C 1 -C 20 alkyl substituted aralkylene and C 1 -C 20 oxyalkylated derivatives thereof; and is 1, 2, or 3.
[0017] Preferably the ethylenically unsaturated tertiary amine is a Michael Addition product of a primary or secondary amine (e.g., an alkyl amine) and two acrylic esters, wherein each of the acrylic esters contains two or more acrylate or methacrylate groups (e.g., wherein the acrylic ester is an acrylate ester or methacrylate ester of an alkane diol, a polyether diol, a glycol, a glycerol). The primary or secondary amine may be selected, for example, from ethyl amines, ethanol amines, diethanol amines and hexamethylene imines and combinations thereof. The acrylic ester may be selected from hexanediol diacrylate, dipropylene glycol diacrylate (DPGDA), tripropylene glycol diacrylate (TPGDA), trimethylolpropane triacrylate (TMPTA), pentaerythritol triacrylate (PETA) and combinations thereof. Examples of commercially available acrylic functional amines are Laromer 8996 (available from BASF); Ebecryl 7100 (available from UCB); Suncure 175 (available from Reichhold); and Ebecryl P-104 (available from UCB).
Stereo Cross-Linkable Ionomer
[0018] It should be noted that the monomeric/oligomeric nature of the ionomer components results in a random distribution of the cationic and anionic charges within the ionomer network. This differs from existing preformed polymeric ionomer pairs in which one of the pair of polymers contains cationic charges while the other contains anionic charges. In the present invention, stereo cross-linkable is defined as the ability of the oligomeric ionomers to randomly polymerize in-situ via two different mechanisms. The first mechanism being a covalent free radical photopolymerization of the resin. The second mechanism being an ionic cross-link between the acidic and basic functional groups of the resin in multiple dimensions at the same time, to form a highly crosslinked polymeric network of infinite molecular mass. For example, the ethylenically unsaturated tertiary amine neutralizing agent provides the counter ion for the acidic ethylenically unsaturated resin, which allows the ionomer formed, to stereo polymerize during photoreaction (via energy curing) and form an additional cross-linked network over the ethylenically unsaturated groups as well as over the ionic structure of the resin. Therefore, unlike other water based energy curable resin technology, where the resistance properties to be imparted by the cured resin composition depend on, and are a function of, the evaporation of the base (e.g. ammonia), for example, which shifts the acid base equilibrium in the post cure composition, here for example, the ethylenically unsaturated tertiary amine neutralizing base, and neutralized resin form an additional cross-linked network instantly on both sides of the ionomer.
[0019] Upon irradiation, either or both of the ions formed from the two oligomeric material formations increase in molecular weight by addition polymerization. The use of (meth)acrylic functional, carboxylic polymeric, and tertiary amine oligomeric resins in an energy curing mechanism results in the formation of a crosslinked ionomer with a ladder structure via the formation of covalent bonds as well as opposing ionic bonds. It is essential that one oligomeric material polymerizes but it is preferred that they both polymerize. After polymerization, a highly crosslinked structure is formed showing exceptional properties over conventional and “water-compatible” energy curable materials existing in the prior art. The use of the present composition in energy curable leads to improved cure, adhesion, hardness, mechanical and solvent resistance properties.
[0020] The water solubility of the polymeric resin salt of the present invention makes it especially suitable for water based energy curing processes while the organic acid/base crosslinking works against the tendency of ionic polymers to become mechanically weaker upon absorption of water. The control of the molecular weight between acidic and basic sites on separate oligomers allows for the formation of highly crosslinked materials which show much less brittle failure than expected for crosslinked ionomers.
[0021] For the synthesis of the resin salt three processes can be used. The first process starts from a solid carboxylic resin, which will be diluted in tertiary acrylic amine and optionally, water. The second process starts with the polymer analog reaction of alcohols with the styrene maleic anhydride resin in a solvent. In a solvent stripping step, the resin will be neutralized and diluted with tertiary acrylic amine. In the third process the solvent of the previous described ester modified resin will be azeotropically distilled with water and partially neutralized with ammonia. Afterward the resin is further neutralized with acrylated amine at 60° C.
Example 1
Comparative
[0022] SMA-1000 (40 grams, available from Atofina) solid is slurried into water (50 grams) and neutralized to pH 6.5 with concentrated NH.sub.4OH (available from Fisher Scientific). The resulting solution was 43% in solids content and had a 31 Pa·s viscosity at 10 s−1 at 40° C.
Example 2
[0023] SMA-1000 (40 grams, available from Atofina) solids is slurried into water (50 grams) and neutralized to pH 6.5 with di(2-hydroxyethyl)methyl amine (15 grams, available from Aldrich) with heating to 60° C. for 12 hours. The resulting solution was 50% solids in content and had a 30 Pa·s viscosity at 10 s−1 at 40° C.
Example 3
[0024] SMA-1000 (35 grams, available from Atofina) solids is slurried into water (50 grams) and neutralized to pH 4.5 with concentrated NH 4 OH (5 grams, available from Fisher Scientific) followed by addition of acrylated amine 16-101 (10 grams, available from Reichhold) and heating to 60° C. for 4 hours. After cooling, the resulting solution was corrected to pH 6.5 with additional concentrated ammonia and measured to be 48% in solids content and had a 48 Pas. viscosity at 10 s−1 at 40° C.
Example 4
Comparative
[0025] As described in U.S. Pat. No. 6,559,222, polymeric resin salt, styrene maleic anhydride copolymer (165 grams) having an acid number of 480 and an average molecular weight of 1000 were added together under agitation to methyl isobutyl ketone (MIBK, 120 grams). The two materials were then heated to approximately 95-110° C. over 1 to 2 hours under a nitrogen blanket. Next, N,N-dimethylbenzyl amine (0.8 grams) and a monofunctional alcohol (18 grams) such as n-propanol, ethanol or octadecanol were then added to form a polymeric mixture having an acid number between 200 to 210. The nitrogen blanket was then removed and 4-methoxyphenol (0.12 grams) and N,N-dimethylbenzylamine (0.36 grams) were added. Over a period, of time, for example 60 to 90 minutes, a hydroxy-functional acrylate such as 4-hydroxybutyl acrylate (55.80 grams) or 2-hydroxy-ethyl acrylate was then added until the acid number of the polymeric mixture is between 130 to 140. The polymeric mixture was then distilled and 4-methoxyphenol (0.12 grams) was added along with ammonium hydroxide (27.90 grams) and deionized water (327.8 grams). The mixture was then heated, for example to 99° C. The MIBK and water were then removed by distillation. When all of the MIBK had been removed, the water is returned to the mixture as a water/ammonia distillate. This material was prepared as a 37% in solids content in water and neutralized to pH 6.5 with ammonia yielding 23 Pa·s viscosity at 10 s−1 at 40° C.
Example 5
[0026] To the resin salt solution (108 grams) as prepared in Example 4 at pH 4.5 (containing 37% resin solids in water prior to the final addition of neutralizing base described in U.S. Pat. No. 6,559,222) at 60° C. was added di(2-hydroxyethyl)methyl amine (10 grams, Aldrich). After cooling, the resulting solution had a pH of 6.5 and was 43% in solids content and 20 Pa·s viscosity at 10 s−1 at 40° C.
Example 6
[0027] To resin salt solution (100 grams) as prepared in Example 4 at pH 4.5 (containing 37% resin solids in water prior to the final addition of neutralizing base described in U.S. Pat. No. 6,559,222) at 60° C. was added acrylated amine 16-101 (15 grams, Reichhold) over four hours. Upon cooling, the resulting solution was corrected to pH 6.5 with concentrated ammonia and measured to be 48% in solids content and had a 37 Pa·s viscosity at 10 s−1 at 40° C.
Example 7
Comparative
[0028] Laromer 8765 (20 grams, available from BASF Corporation, Mount Olive, N.J.) was added to the resin salt solution (25 grams) as prepared in Example 1, Irgacure 2959 (1.5 grams, available from Ciba) was then added to this solution. To complete the solution for coating, water (3 grams) and TegoRad 2200N (0.5 grams available from TegoRad Corporation) were added with stirring, and the solution set aside for 12 hours to clear the entrained air before coating and curing. The viscosity of coating solution was 0.35 Pa·s at 25° C.
Example 8
[0029] Laromer 8765 (17.5 grams, available from BASF) followed by Irgacure 2959 (1.5 grams, available from Ciba) were added with stirring to resin salt solution in water (27 grams) as prepared in Example 2. water (3.5 grams) and TegoRad 2200N (0.5 grams available from TegoRad Corporation) were then added with stirring, and the solution set aside for 12 hours to clear the entrained air before coating and curing. The viscosity of coating solution was 0.38 Pa·s at 25° C.
Example 9
[0030] Laromer 8765 (17.5 grams, BASF) followed by Irgacure 2959 (1.5 grams, available from Ciba) were added with stirring to resin salt solution in water (30.5 grams) as prepared in Example 3. TegoRad 2200N (0.5 grams available from TegoRad Corporation) was then added with stirring, and the solution set aside for 12 hours to clear the entrained air before coating and curing. The viscosity of coating solution was 0.52 Pa·s at 25° C.
Example 10
Comparative
[0031] Laromer 8765 (17.5 grams, BASF) followed by Irgacure 2959 (1.5 grams, available from Ciba) were added with stirring to resin salt solution in water (30.5 grams) as prepared in Example 4. TegoRad 2200N (0.5 grams, available from TegoRad Corporation) was then added with stirring, and the solution set aside for 12 hours to clear the entrained air before coating and curing. The viscosity of the coating solution was 0.23 Pa·s at 25° C.
Example 11
[0032] Laromer 8765 (17.5 grams, available from BASF) followed by Irgacure 2959 (1.5 grams, available from Ciba) were added with stirring to resin salt solution in water (30.5 grams) as prepared in Example 5. TegoRad 2200N (0.5 grams, available from TegoRad Corporation) was then added with stirring, and the solution set aside for 12 hours to clear the entrained air before coating and curing. The viscosity of the coating solution was 0.28 Pass at 25° C.
Example 12
[0033] Laromer 8765 (18.0 grams, available from BASF) followed by Irgacure 2959 (1.5 grams, available from Ciba) were added with stirring to resin salt solution in water (30 grams) as prepared in Example 6. TegoRad 2200N (0.5 grams, available from TegoRad Corporation) was then added with stirring, and the solution set aside for 12 hours to clear the entrained air before coating and curing. The viscosity of the coating solution was 0.25 Pa·s at 25° C.
Example 13
[0034] The coating solutions described in Examples 7 to 12 were applied by #3 and #5 wire-wound rods to Uncoated Leneta N2A charts (Leneta is a product and trademark of The Leneta Company, 15 Whitney Rd, Mahwah, N.J.). Immediately following coating, the wet film was cured by passing under 650 mJ/cm 2 of UV light (two medium pressure Hg lamps at 300 W/in each, 200 fpm on an RPC Industries processor) in air. The resulting cured surfaces were conditioned at 75° F. and 48% Relative Humidity for one day and the following measurements taken. Gloss was measured at 60-degree angle using a type DIN Geproft 4501 meter from BYK Gardner parallel to the coating direction. The rub resistance (an methyl ethyl ketone (MEK) rub and water rub test) was determined by wetting the cured coating surface and employing light finger pressure to rub the coating off as detected by the exposure of the underlying ink. The number of complete back-and-forth cycles required were recorded. Coating adhesion was measured by taking a convenient length of 610 tape (available from 3M Co., St. Paul, Minn.), laminating the tape to the cured surface under finger pressure, then lifting the tape from the surface in one rapid motion at right angle to the coated surface. The adhesion was rated a pass when the coating remained completely intact and adhered to the substrate following tape peel. The coating weight was determined gravimetrically by the difference in weight between a 10 cm.times.10 cm piece cut from the coated area and an identical size piece cut from a similar area of uncoated stock. Each measurement reported in Table 1 below is normalized to the same dry coating weight (4 g/m.sup.2).
[0000]
TABLE 1
Example
Gloss
MEK Rub
Water Rub
Adhesion
7 (comparative)
65
6
5
fail
10 (comparative)
89
12
18
pass
11
91
12
16
pass
12
95
35
20
pass
[0035] Those skilled in the art having the benefit of the teachings of the present invention as hereinabove set forth, can effect numerous modifications thereto. These modifications are to be construed as being encompassed within the scope of the present invention as set forth in the appended claims. | A homogenous, aqueous, energy curable, stereo cross linkable ionomer containing coating composition and a method of preparing same. | 2 |
BACKGROUND OF THE INVENTION
The present invention relates to a wear resistant cylinder such as an Al alloy tappet in which the outer circumferential surface is coated with a hard film, and a method of manufacturing it.
A tappet body used in a direct acting type valve operating mechanism in an internal combustion engine is generally formed from Fe material such as steel and cast iron. Recently, in order to lighten the valve operating system, it is inclined to be made of Al alloy.
However, Al alloy tappet provides lower mechanical strength and lower wear resistance than Fe material. Thus, when the tappet is inserted in a cylinder head made of the same material, Al alloy, the sliding surface is likely to wear earlier or to cause scoring.
To solve the problem, the outer circumferential surface of Al alloy tappet may be coated with wear resistant material which is different from a base metal. If the outer circumferential surface of the base metal is flat, adhesion strength of the wear resistant material is low, and high peel resistance is not available, so that it is necessary to perform preliminary treatment for the base metal to make the whole outer circumferential surface of the tappet to a rough surface.
To make the rough surface, blasting is generally applied, but for the treatment, it is necessary to employ a specialized blasting apparatus, which takes a long time to involve low productivity and high consumption of blasting material, thereby increasing manufacturing cost.
To overcome the problem, U.S. Pat. No. 5,605,122 issued to Nobuo Hara et al. discloses a tappet in which the outer circumferential surface is made to a rough surface by simple means and is coated with wear resistant material.
Describing the invention in the U.S. Patent, as shown in FIG. 10 of an attached drawing, the whole outer circumferential surface of Al alloy cylindrical tappet is made to a threaded uneven surface 2 which comprises a projection 2a and a groove 2b, and is thermally sprayed to form a film 3.
The whole outer circumferential surface of the tappet body comprises the uneven surface 2 and the film 3 thereon. The projection 2a and groove 2b provide high adhesion strength of the film 3 to the base metal to improve peel resistance in an axial direction. But, in a circumferential direction, there is neither adhesiveness nor frictional resistance by the projection and groove, so that high peel resistance is not obtained, thereby providing low durability or reliability of the tappet.
SUMMARY OF THE INVENTION
To overcome the foregoing problem, it is an object of the present invention to provide a wear resistant cylinder such as an Al alloy tappet and a method of manufacturing it in which a projection and a groove of the outer circumferential surface of the cylinder is modified in form, thereby improving peel resistance of a film to a base metal in both axial and circumferential directions.
According to one aspect of the present invention, there is provided a wear:resistant cylinder which comprises a cylinder body; a projection on an outer circumferential surface of the cylinder body; a groove which is formed adjacent to the projection on the outer circumferential surface of the cylinder body; and a wear resistant film with which the projection and the groove on the outer circumferential surface are coated, a recess being formed on a ridge of the projection.
Not only in the axial direction of the cylinder body but also in the circumferential direction, peel resistance of the film is improved, thereby increasing durability and reliability of the cylinder.
According to another aspect of the present invention, there is provided a method of manufacturing a cylinder, the method comprising the steps of forming a projection and a groove alternately on an outer circumferential surface of a cylinder body, an uneven surface being formed on a ridge said projection at the same time, and coating the outer circumferential surface of the cylinder body with a wear resistant film.
It avoids conventional blasting, thereby facilitating manufacturing of the cylinder, such as a tappet, and decreasing cost.
According to a further aspect of the present invention, there is provided a method of manufacturing a wear resistant cylinder, the method comprising the steps of forming a projection and a groove on an outer circumferential surface of a cylinder body; cutting off a ridge of the projection by a suitable length in a circumferential direction to form an uneven surface; and coating the outer circumferential surface of the cylinder body with a wear resistant film.
According to a still further aspect of the present invention, there is provided a method of manufacturing a cylinder, the method comprising the steps of forming an optional groove on an outer circumferential surface of a cylinder body; pressing a sharp cutting tool against the outer circumferential surface of the cylinder body to move the cutting tool in an axial direction to form a helical groove and a helical projection which has an uneven surface on a ridge while the cylinder body is rotated; and coating the outer circumferential surface of the cylinder body with a wear resistant film.
The recess is formed without fail, thereby increasing reliability.
BRIEF DESCRIPTION OF THE DRAWINGS
The features and advantages of the present invention will become more apparent from the following description with respect embodiments as shown in the drawings wherein:
FIGS. 1(A) and (B) show an embodiment of the first method in order of steps, (A) being a partially vertical sectioned front view of a tappet body which has a helical projection and groove on the outer circumferential surface, (B) being a partially vertical sectioned front view which shows the outer circumferential surface onto which a film is thermally sprayed;
FIG. 2 is an enlarged view of a portion (X) in FIG. 1;
FIG. 3 is an enlarged view of a portion (Y) in FIG. 1;
FIG. 4 is a horizontal sectional plan view taken along the line IV--IV in FIG. 3;
FIG. 5 is an enlarged sectional view which shows how to form a projection, a groove and an uneven surface;
FIG. 6 is an enlarged view of a portion (Z) in FIG. 1;
FIG. 7 is a sectional view similar to FIG. 5, showing an embodiment of the second manufacturing method;
FIG. 8 is a perspective view of another embodiment of the second manufacturing method;
FIG. 9 is a perspective view of an embodiment of the third manufacturing method; and
FIG. 10 is a partially vertical sectional view which shows a conventional method of manufacturing a tappet.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
FIG. 1 (A) and (B) illustrate a method of the present invention in order of steps.
A cylindrical tappet body 1 is made of conventional Al alloy such as A1--Si--Cu, and has a bore la in which a shim (not shown) made of wear resistant metal fits, on the upper surface.
As shown in FIG. 1(A), the outer circumferential surface of the tappet body 1 comprises an uneven surface 2 which comprises a helical projection 2a and groove 2b having a predetermined pitch, and as shown on an enlarged scale in FIGS. 2 to 4, an uneven surfaces 2c are formed on the projection 2a at regular intervals, such as 0.1 to 3 mm in a circumferential direction.
To form the projection 2a, groove 2b and uneven surfaces 2c, there is a method as follows.
The first method is a method of forming the projection 2a, groove 2b and uneven surfaces 2c simultaneously. As shown on an enlarged scale in FIG. 5, the tappet body 1 is held horizontally by a chuck (not shown) and is rotated at fixed speed, and a sharpened threading tool 4 is pressed against the outer circumferential surface of the tappet body 1. The threading tool 4 is moved in a direction of an arrow, i.e. in an axial direction, so that the surface of the tappet body 1 is cut to form the helical projection 2a and groove 2b.
To overlap a circumferential cutting width "W" partially formed by the cutting tool 4, or to form an overlapping portion "L" as shown in FIG. 5, by suitably determining depth "H" of cut on the surface of the tappet body 1 by the cutting tool 4, an opening angle "θ" of the cutting tool 4, and an axial feed rate of the cutting tool 4 per one rotation of the tappet body 1 or a pitch "P" of the projection 2a or groove 2b, a ridge of the projection 2a is discontinuously chipped in a direction contrary to a feed direction of the cutting tool 4 to form a plurality of discontinuous uneven surface 2c.
To form the overlapping portion "L", the relationship among the depth "H" of cut, the opening angle "θ" and the pitch "P" may be set to H tanθ/2≧P/2.
The inventors of the present invention confirmed that the uneven surface was formed on the outer circumferential surface of the tappet body 2 having a diameter of 20 to 50 mm to form the uneven surface 2c easily by setting the opening angle θ of the cutting tool 4° to 30° to 90°, the overlapping portion "L" to 0.05 to 0.35 mm, a rake angle to 20°, a back clearance angle to 25°, the pitch "P" of the projection and groove to 0.10 to 1.00 mm and the depth of cut to 0.25 to 0.80 mm.
The following is presumed. As mentioned above, the pitch decreases compared with conventional threading, a suitable overlapping portion "L" is provided between the cutting width "W" of the cutting tool 4, so that axial thickness of the ridge 2d of the projection 2a decreases. Further, the ratio of the depth "H" of cut to the pitch "P" increases and the diameter of the ridge of the projection 2a is made to be smaller than the diameter of the tappet body 1, so that reaction force in a contrary direction to feed by cutting resistance is applied to the cutting tool 4. Thus, in the tappet body 1 made of low toughness Al alloy, the ridge 2d is pressed by the reaction force, and the uneven surface 2c is formed by being cut off in a circumferential direction.
The outer circumferential surface of the tappet body 1 is formed as a roughened surface, and as shown in FIG. 1 (B), wear resistant metal such as Fe is thermally sprayed to the outer circumferential surface which comprises a roughened surface to form a film 3. The film 3 is formed as above, thereby making a tappet which provides not only axial but also circumferential high peel resistance of the film 3. There is a problem that adhesion strength of the film 3 is conventionally low in a circumferential direction, but as shown in FIGS. 4 and 6, according to the present invention, thermal spraying material is coated onto the plurality of uneven surfaces 2c formed on the projection 2a, thereby providing high adhesion effect of the film 3 in the circumferential direction to cause high peel resistance.
The uneven surfaces of the recesses 2c which are formed by cutting off the ridges 2d are not as smooth as mechanically processed surfaces, but are irregularly roughened, thereby providing suitable peel resistance to the film 3 thermally sprayed onto the surface, which is advantageous.
The second method comprises the steps of forming the projection 2a and the groove 2b and, thereafter, cutting off the ridge 2d of the projection 2a at a suitable length in a circumferential direction to form the uneven surfaces at regular intervals.
The second method comprises the steps of forming the helical projection 2a and groove 2b on the outer circumferential surface of the tappet body 1 by pressing and moving the cutting tool 4 on the outer circumferential surface of the tappet body 1 in an axial direction of the tappet body 1 while the tappet body 1 is rotated at fixed speed, and thereafter by moving the cutting tool 4 in a contrary direction (as shown by a solid arrow in FIG. 7) to a formerly moving direction (as shown in a broken arrow in FIG. 7) to form uneven surfaces (not shown) at regular intervals on the ridge 2d of the projection 2a by the cutting tool 4.
The pitch in returning the cutting tool 4 may be equal to the pitch "P" in going forth, but preferably may be significantly larger than it.
When the relationship among the depth of cut "H", the opening angle "θ" and the pitch "P" is set to H tanθ≧P/2 in a forwarding path, the irregular uneven surfaces 2c as above are formed on the ridge 2d of the projection 2a with cutting of the projection 2a. Further, when the cutting tool 4 returns, deeper recesses are formed on the ridge 2d by the cutting tool 4. Two kinds of shallower and deeper recesses improve circumferential peel resistance of the film thermally sprayed thereafter.
As another embodiment of the second method, while the tappet body 1 is rotated at fixed speed similar to the above, the sharp cutting tool 4 is pressed against the outer circumferential surface of the tappet body 1 to move the tappet body 1 in an axial direction, thereby forming the helical projection 2a and groove 2b on the outer circumferential surface of the tappet body 1. Thereafter, as shown in FIG. 8, onto the outer circumferential surface having unevenness, a pressing roller 5 on which a plurality of protrusions 5a extends axially (or in a direction crossed to the projection) is put in parallel with the tappet body 1 and pressed onto it. The pressing roller 5 and the tappet body 1 are rotated at the same circumferential speed in a contrary direction, recesses (not shown) are formed at regular intervals on the ridge 2d of the projection 2a by the protrusions 5a of the pressing roller 5.
According to this method, the ridge 2d of the projection 2a are pressed by the protrusions 5a of the pressing roller 2a to form the uneven surfaces. Burrs (not shown) which are formed at the edges of the uneven surfaces to prevent a film thermally sprayed thereafter from peeling off, thereby increasing peel resistance of the film, which is advantageous.
As a method of forming uneven surfaces on the ridge 2d of the projection 2a, in addition to the method which uses the pressing roller 5, there is a method of moving a thinner grinding wheel or a milling tool in an axial direction which is perpendicular to the projection 2a. Any of the methods may be applied.
In the third method, an optional groove is formerly formed on the outer circumferential surface. Thereafter, while the tappet body 1 is rotated around its axis, a sharp cutting tool is pressed against the outer circumferential surface to move the tappet body 1 axially, thereby forming a groove and a projection which has recesses at regular intervals on its ridge.
For example, as shown in FIG. 9, on the outer circumferential surface of the tappet body 1, a plurality of V-sectioned grooves which extend axially are formed by a rotary grindstone or a milling machine (not shown) at suitable intervals in a circumferential direction. Thereafter, similar to what is shown in FIG. 5, while the tappet body 1 is rotated around its axis, a sharp cutting tool 4 is pressed against the outer circumferential surface of the tappet body 1 to form uneven surfaces at regular intervals on a ridge 2d of a helical projection 2a.
Thereafter, similarly, a film is formed on the outer circumferential surface of the tappet body 1 by thermal spraying. Similar advantages to the second method can be achieved according to the third method. The present invention is not limited to the foregoing embodiments. For example, in the foregoing embodiments, the projection 2a and the groove 2b are helical, but a plurality of annular projections and grooves spaced in parallel to each other may be formed, and a plurality of uneven surfaces may be formed on the annular projections 2a. Instead of the above thermal spraying, the film 3 may be formed by plating or coating means. The present invention may be applied to an air cylinder, a piston of a hydraulic cylinder, a piston of an internal combustion engine, etc. in addition to an Al alloy tappet.
The foregoings merely relate to preferred embodiments of the present invention. Various changes and modifications may be made by person skilled in the art without departing from the scope of claims wherein: | A tappet made of Al alloy is used in a valve operating mechanism of an internal combustion engine of a vehicle. On the whole outer circumferential surface of the tappet, a helical projection and a helical groove are formed alternately to form an uneven surface. A plurality of uneven surfaces are formed on a ridge of the projection at regular intervals. The outer circumferential surface is coated with a wear resistant Fe film by thermal spraying. The uneven surfaces on the projection provide high adhesion strength of the film to the outer circumferential surface of the tappet to improve peel resistance, thereby increasing durability and reliability of the Al alloy tappet. | 5 |
This is a divisional of co-pending application Ser. No. 08/329,794 filed on Oct. 26, 1994.
FIELD OF THE INVENTION
The invention is directed to the vacuum coating of workpieces such as data storage disks using a continuous, valveless vacuum vessel for processing.
BACKGROUND OF THE INVENTION
The sputtering process or other deposition process that is performed in near vacuum controlled atmospheres, occurs in a chamber that is first evacuated and thereafter partially pressurized with small amounts of gas to create a minute partial atmosphere of desired composition. Multiple operations are commonly achieved with a single pump down or initial evacuation of a multiple stage, valved chamber by evacuating the chamber initially and then repressurizing to the desired partial atmosphere and reevacuating the chamber during each movement of work between stations as different coatings are applied at successive positions within a single sputtering device.
Typical of such devices is the continuous vapor deposition system of U.S. Pat. No. 5,016,562 wherein a series of modules are separated by valves and each deposition module is preceded and succeeded by an isolation module in addition to the entrance and exit load lock modules. U.S. Pat. No. 4,048,955 illustrates a vapor deposition mechanism wherein a series of processing cells or chambers are separated and isolated by above atmospheric nitrogen seals to exclude the ambient outside atmosphere.
Current rigid disk sputtering machine designs have evolved from semiconductor and thin film head applications with few modifications other than accommodating dual sided deposition. Also, system manufacturers, with limited experience or understanding with respect to thin film disks, have provided machines with overly complex designs in order to accommodate options such as substrate biasing, RF etching and RF sputtering. This complexity adds not only to initial cost, but also adds ongoing maintenance cost and reduced reliability. These sputter system manufacturers attempt to make their machines more versatile to broaden the market base by including features such as isolated process chambers, repetitive pump down to high vacuum and product versatility.
SUMMARY OF THE INVENTION
The present invention uses a valveless mechanism that is inherently more simple and less costly. A modular, but continuous vacuum vessel is used for processing. Differential pumping and gas showers are utilized to isolate the individual process stations with isolation valves used only at load lock stations where parts enter and leave the system. By eliminating chamber isolation valves and incorporating side entry of the load and unload lock stations, the main drive system is greatly simplified to a single continuous transport chain. Transfer of disk substrates from one chain drive to another is eliminated. Since isolation valves are required only at load lock stations, the linear inline configuration of the process vessel allows for modularization and expansion of the system to accommodate additional process steps or altered process steps or techniques and for pre and post sputter operations.
The system includes loading and unloading stations and intermediate modular units each of which includes processing stations and an evacuating pump mechanism. The system provides a continuous evacuated chamber or valveless device that is not partitioned and wherein workpieces are moved from processing station to processing station on a continuous transport device, such as a chain drive on which work carrying pallets are mounted at uniform intervals.
The processing stations are separated from one another by the near vacuum of the evacuated chamber and supplied with process gas to maintain a desired atmosphere and elevated pressure within the respective process chambers. Such processing pressure is an incrementally higher pressure than the intervening evacuated chamber environment, typically a ten to one pressure differential.
The processing chamber assemblies are comprised of two aligned units mounted coaxially at opposite sides of the workpieces carried on the transport to define a slotted opening therebetween through which the workpieces pass to enter and exit the station. Sputter deposition processes have evolved to the point that relatively high process pressures (10 to 40 microns Hg) are routinely employed, while turbomolecular vacuum pumps used to pump down the evacuated chamber obtain maximum throughput at about 1 micron Hg. Accordingly, the required 10 to 1 pressure differential is obtained utilizing the low conductance slits through which the work passes to and from the processing chambers and the gas supply without additional hardware. Further the mean free paths at these process pressures are less than 1 cm, so impurities are not able to diffuse into the process chamber making unnecessary hard valve isolation. Finally, the use of connecting tunnels with gas showers at the top further cleanse the disk substrates and wash impurities in the direction of the pump. Gas emanates from the shower jets with near supersonic velocity and as such has a nonstochastic momentum distribution directed preferentially across the disk surface and toward the pump.
To make a deposition device cost effective for producing products such as coated data storage disks it is important to minimize the complexity and cost of the system. Other measures of cost effectiveness are the throughput and the idle time required for service and target replacement. The single vacuum envelope design is inherently simpler and less costly than the commonly used valved structures for separation of adjoining process stations or the viscous isolation structures that are an alternative. Throughput can be enhanced by partitioning the longer operations among successive workstations to reduce the duration of the longest process time at a single workstation that would determine the overall output of the entire system. Downtime is minimized by the use of work station and load lock assemblies that can be readily released from the modular unit and replaced to enable most service and target replacement to be conducted offline while the system is in operation.
The disk processing system as shown and described contemplates a disk sputtering system that typically applies as consecutive sputtered coatings; an underlayer, a magnetic layer which is commonly a cobalt alloy and a protective, abrasion resistant overcoat such as amorphous carbon. The system could also be used for or in combination with other processes requiring a reduced pressure process atmosphere such as chemical vapor deposition, evaporative coating or sputter etching and would probably include process stations for pre and post sputtering processes such as heating or lubing.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is an isometric view of the structure of a sputtering system including the present invention. FIGS. 2 and 3 are elevation and plan views respectively of the structure of FIG. 1. FIG. 4 is a section view taken along line 4--4 of FIG. 2. FIG. 5 is a section view taken along line 5--5 of FIG. 2. FIGS. 6 and 7 are elevation and plan views respectively of the transfer rods used to load and unload workpieces into and out of the sputtering system. FIG. 8 is a section view taken along line 8--8 of FIG. 2. FIGS. 9 and 10 are respectively elevation and plan views of the system transport structure of the invention including the trolley and pallet. FIG. 11 is an elevation view of a modular processing unit including the vacuum pump.
DETAILED DESCRIPTION
FIGS. 1, 2 and 3 are each a partial view of the sputtering system of the present invention. A pair of terminal housings 4, 6 and the intervening modular process unit or units 8 form a single vacuum envelope or chamber. The parts or workpieces are loaded at a load lock 10 which is isolated by valves 12, 14 and attached to the system through an opening in the terminal housing 4. A similar device removes the workpieces at the load lock 16 mounted on the other terminal housing 6. Each of the modular process vessels 8 includes a turbomolecular vacuum pump 18 which is effective to reduce the vacuum envelope to a pressure of one micron of mercury (Hg). Each of the terminal housings 4, 6 and modular process units 8 are mounted on tables 20 to enable the interchange of units and the use of the number of processing modules required for the specific process.
FIGS. 9 and 10 show the manner in which the disk substrate workpieces 22 are carried past the workstations. A continuous chain drive element 23 is connected to the middle of a trolley 24. The trolley 24 includes a set of four rollers 25 that support the carriage assembly on the bed plate surface 26. Other rollers 27 mounted on the transport support assembly guide trolley 24 to restrain lateral movement. Rigidly attached to trolley 24 is a pallet 28 which presents three grooved projections 29 that receive and support the disk workpiece 22 in a vertical position. The modular unit workstations 30 are uniformly spaced and a like spacing is maintained between adjacent trolleys 24 on the drive chain 23 such that all work stations may function simultaneously as work pieces are moved through a series of indexed positions. Power for the transport mechanism is provided by a motor 32 (FIG. 4) mounted on one of the terminal housings 6. The shaft 33 which rotates in unison with sprocket 34 to move the trolleys 24 is driven by motor 32 through belt 35 and pulleys 36, 37. The trolleys 24 are carried above the chain 23 from the load station in terminal housing 4, through the processing stations 30 of modular units 8 and to the unloading station within the opposite terminal housing 6. The trolleys 24 with the attached unloaded pallets 28 are returned through a lower portion of the vacuum envelope as seen in FIG. 5. Through much of the return travel the trolley margins are confined in grooves 38 (FIG. 8).
FIGS. 5, 6 and 7 show the loading and unloading mechanism. The load and unload functions are substantially identical with the sequencing being reversed to successively load thirty (30) pallets within one terminal housing and successively unload thirty (30) pallets at the opposite terminal housing. A cassette 40 containing thirty (30) disks is inserted into the load lock 10 by opening valve 12 with valve 14 closed and the transfer mechanism withdrawn to the right (as seen in FIG. 5). With valve 12 closed and valve 14 open, the transport rod 41 is advanced to the position shown in FIG. 5 where the rod extends through the central openings of the disks supported in the cassette 40. As seen in the respective elevation and plan views of FIGS. 6 and 7, the transport rod 41 has thirty (30) grooves 42 with angled guide surfaces 43 at each side of each groove to permit all thirty (30) disks within the cassette to be aligned and picked up simultaneously.
The transfer mechanism 57 is of commercially available design with the principal moving assembly, that moves in unison with the disk transport rod 41, having three degrees of freedom, the X, Y and Z axes as viewed in FIG. 5. The transport mechanism includes a moving portion that slides on a frame 46 and is shrouded by an accordion pleated cover or shroud 39 which encloses a portion exterior of the terminal housing 4. With the rod 41 approximately coaxial with the center openings of the disks supported in cassette 40 within the load lock 10, the transfer mechanism (shown in part) advances from the retracted dotted line position 45, 45' to the advanced solid line position 44, 44'. This aligns the grooves 42 respectively with the disks in the cassette 40. The rod 41 is then lifted upward or elevated in the direction of the Y axis to lift the disks from the cassette 40. Rod 41 with the disks supported thereon is retracted to align the outermost disk on the rod 41 with the next pallet 28 arriving at the loading station. The rod 41 is then lowered and retracted so that the disk is transferred from rod 41 to the pallet and the distal end of the support rod is clear of the disk and pallet at the load station. The transport mechanism may now be indexed to bring the next successive pallet to the load location. The transfer mechanism is then successively advanced to align the next disk from the distal end of the rod with the pallet 28 at the load station, lowered to place the disk in the grooved projections 29 and retracted to allow the transport mechanism to be indexed. This sequence is reversed to sequentially unload the processed disks at the opposite end of the transport and load thirty (30) disks into a cassette supported in the load lock 16 adjacent the unloading site.
Though not shown herein, the transfer mechanism may include optical sensing to make more precise the positioning of the transfer rod within the openings of the disks within the cassette 40 at the load lock and to align the grooves 42 with disks in the cassette 40 and align a disk in a groove 42 with the grooved projections 29 of a pallet 28. At the unloading site the selected groove 42 is aligned with the disk supported by the grooved projections 29 of a pallet 28 and subsequently the disks supported in transfer rod grooves 42 are aligned with the corresponding support grooves in the cassette 40 positioned in the load lock 16.
If necessary, it would be possible to further isolate the adjoining workstations 30 from one another by a gas shower positioned between work stations. A delivery conduit mounted at the inside of the top wall of the modular process unit 8 can release a small amount of an inert gas through a narrow slotted opening or the equivalent to introduce a sheet of isolating gas atmosphere. The isolating gas moves from the slotted outlet to the turbomolecular vacuum pump at the bottom of the modular process unit 8 at a near supersonic velocity to not only enhance isolation between adjoining work stations, but also to purge the surfaces of disks indexing between the adjoining work stations.
The section view of FIG. 8 shows one of the process stations 30 at which a disk substrate 22 supported on a pallet 28 moves between sputtering targets 48. Coaxial flanged extension tubes 49 are mounted at openings in the modular process vessel 8. The sputtering station units include a flanged plate 50 to which is mounted a tubular enclosure element 51, a gas supply tube 52 and the power supply connection 53 leading to the sputtering target 48. A tube 54 telescoped over the tubular enclosure element 51 completes the process station enclosure wherein gas delivered through the tube 52 maintains a desired atmosphere. The tube 54 presents a flange 55 at the distal end that defines a circular opening of approximately the same diameter as the circular disk substrate workpiece 22. The pallet 28 and disk substrate workpiece 22 are indexed to place the workpiece in alignment with the circular openings in flanges 55 for the sputter coating of both sides simultaneously. The work piece and the supporting pallet are moved through the slotted opening or gap 56 between the tube flanges 55 to effect movement into and out of the sputter process station 30. The process gas is supplied through the tube 52 to maintain the atmosphere of a desired composition within the chamber defined by the flange plate 50 and tubular elements 51, 54. The slotted opening 56 between the flanges 55 provides sufficient restriction to isolate the process chamber from adjoining process chambers within the near vacuum envelope. The pressure of the process gas atmosphere within the process chamber is maintained at 10 to 40 microns Hg while the continuously pumped down vacuum envelope pressure approaches 1 micron Hg.
In operation the terminal housings 4, 6 and the intervening modular process units 8 (with four processing stations 30 provided in each unit as shown) afford a single evacuated chamber or vacuum envelope that surrounds the single inline workpiece transport assembly and isolates the process stations 30 from one another. The processing or work stations include two units which are aligned and mounted on opposite side walls of the modular process unit 8 to provide process chambers separated by a slit or slotted opening 56 through which the workpiece 22 and pallet 28 move to index the workpiece into and out of the sequence of work stations. The vacuum envelope defined by the space enclosed by the process modules and the terminal housing units is maintained at a near vacuum by the turbomolecular vacuum pumps 18 that form a part of each modular process unit 8 to achieve a vacuum approaching one micron of Hg. The slotted opening 56 associated with the workstations is sufficient to restrict the depletion of process gases supplied to the process chamber 58 and maintain a desired localized atmosphere of 10 to 40 microns Hg pressure without further control devices while effectively isolating adjoining work stations from one another.
The system is essentially valveless with a single chain conveyer used to move parts 22 along a linear path. Thus there is no requirement that the parts in process be moved from one conveying device to another. The only valves used in the system are those associated with the load lock stations 10, 16 where workpieces are loaded into the system and removed from the system at the opposite end of the linear path. Parts are loaded and unloaded at right angles to the linear processing path that functions within the single uninterrupted vacuum envelope.
A wide variety of process steps may be used with the multiple station availability. Multiple sputtering operations may be undertaken and also presputtering and post sputtering operations. Also to optimize system effectiveness the same operations may be performed at successive stations. If for example, one sputter operation requires 80 seconds of process time and two other companion operations require 20 seconds each, the output of the system would be enhanced by a factor of four by having the 80 second operation broken down into 20 second processes at four successive stations. The system would then not be constrained by the one excessively long process time.
While the invention has been particularly shown and described with reference to a preferred embodiment, 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. | A vacuum deposition system is shown in the form of a sputtering system for rigid disk substrates which uses a single vacuum envelope and a single transport to avoid multiple pump downs or valved isolation structures during the multiple coating processes or the transfer of workpieces between conveyer devices. Work stations carried by a modular processing unit provide a slotted opening through which work pieces supported on the transport enter and leave the work station and which affords sufficient restriction to enable a processing gas atmosphere to be maintained within the work station that is above the pressure of the vacuum envelope while being isolated from the adjoining work stations. The work stations are supported on and readily releasable from the modular processing units to allow service and target replacement to occur offline. The work station process steps that are of longest duration are partitioned to be performed at multiple successive work stations to make work station processing times as equal as possible and enhance system throughput. | 2 |
REFERENCE TO RELATED APPLICATIONS
[0001] This application is a Divisional of U.S. patent application Ser. No. 14/008,057, filed Oct. 21, 2013, which is a 35 U.S.C. §371 U.S. national entry of International Application PCT/US2012/030519, having an international filing date of Mar. 26, 2012, which claims the benefit of U.S. Provisional Application No. 61/468,194, filed Mar. 28, 2011, the content of each of the aforementioned applications is herein incorporated by reference in their entirety.
STATEMENT OF GOVERNMENTAL INTEREST
[0002] This invention was made with government support under grant no. CA146799, awarded by the National Institutes of Health. The government has certain rights in the invention.
BACKGROUND OF THE INVENTION
[0003] As in the case of most diseases, in order to improve the prognosis of patients, a diagnosis at an early stage is crucial. For example, esophageal cancer (EC), the 8th-most common malignancy and 6th most frequent cause of cancer death worldwide, exhibits highly aggressive behavior. Barrett's esophagus (BE) is the obligate precursor lesion of esophageal adenocarcinoma (EAC), one of the two major histologic subtypes of EC. Early detection and close periodic surveillance of BE is the best means to intervene in BE-associated neoplastic progression (BN). Existing methods for detecting EC are endoscopic biopsy and histopathological examinations, but they are limited due to their invasive nature and inability to be applied in large-scale studies.
[0004] As many as 3 million Americans harbor BE; however, 40% or more of EACs are diagnosed in subjects lacking any previous symptoms, and only 5% of patients presenting with EAC carry an antecedent diagnosis of BE. Early detection and close periodic surveillance of BE is the best means to intervene in BE-associated neoplastic progression (BN). Nevertheless, EAC develops in only 0.5%-1.0% of previously diagnosed BE patients annually. Thus, most patients presenting with EAC have not benefited from endoscopic (EGO) surveillance of BE. EGO is unsuitable and impractical for population-based screening or detection of asymptomatic BN. Furthermore, performing EGO based only on symptoms risks missing patients with asymptomatic BE and/or EAC. Noninvasive diagnosis of BE would enroll a higher proportion of individuals with BE into EGO surveillance programs before they develop EAC, increasing BN diagnosis at earlier, more survivable stages. At the same time, noninvasive diagnosis of EAC would also improve outcome.
[0005] MicroRNAs (miRNAs or miRs) are short RNA oligonucleotides of approximately 22 nucleotides that are involved in gene regulation. MicroRNAs regulate gene expression by targeting mRNAs for cleavage or translational repression. Although miRNAs are present in a wide range of species including C. elegans, Drosophila and humans, they have only recently been identified. More importantly, the role of miRNAs in the development and progression of disease has only recently become appreciated. Deregulated miRNA expression is implicated in onset and progression of different diseases including, but not limited to embryonic malformations and cancers.
[0006] As a result of their small size, miRNAs have been difficult to identify using standard methodologies. A limited number of miRNAs have been identified by extracting large quantities of RNA. MiRNAs have also been identified that contribute to the presentation of visibly discernable phenotypes. Expression array data shows that miRNAs are expressed in different developmental stages or in different tissues. The restriction of miRNAs to certain tissues or at limited developmental stages indicates that the miRNAs identified to date are likely only a small fraction of the total miRNAs.
[0007] Therefore, there still exists an imperative need to develop robust and reliable molecular diagnostic screening tools for the early detection of BE and/or EAC that will enhance the likelihood of cure and reduce the incremental costs for the treatment of advanced disease.
SUMMARY OF THE INVENTION
[0008] In one or more embodiments, the present invention provides an array of miRNA biomarkers that are detectable in the blood or serum of subjects, which comprise a noninvasive diagnostic technology that is sufficiently sensitive to detect oncogenic, cancerous, premalignant or metaplastic changes in the gastrointestinal tract of a mammalian subject.
[0009] In accordance with an embodiment, the present invention provides an array of oligonucleotide probes for identifying miRNAs, or portions or fragments thereof, in a sample, comprising probes that each selectively bind a mature miRNA, or a portion or fragment thereof, and a platform, wherein the probes are immobilized on the platform, wherein at least two probes selectively bind a human miRNA selected from human miRNAs comprising sequences of SEQ ID NOS: 1-7 and 10-14, or portions or fragments thereof, or at least two probes are selected from probes comprising sequences of SEQ ID NOS: 1-7 and 10-14, or portions or fragments thereof.
[0010] In accordance with another embodiment, the present invention provides a biochip comprising a solid substrate, and further comprising at least two oligonucleotide probes which selectively bind a human miRNA selected from human miRNAs comprising sequences of SEQ ID NOS: 1-14, or portions or fragments thereof, or at least two probes are selected from probes comprising sequences of SEQ ID NOS: 1-14, or portions or fragments thereof, which are capable of hybridizing to a target sequence under stringent hybridization conditions and attached at spatially defined address on the substrate.
[0011] In accordance with an further embodiment, the present invention provides a method of determining oncogenic, cancerous, premalignant or metaplastic changes the esophagus or gastrointestinal tract of a mammalian subject comprising (a) extracting miRNA from a sample obtained from a mammalian subject, (b) contacting the miRNA from (a) with the array or the biochip as described above, (c) performing an analysis using the array or biochip of b) to determine expression of at least one miRNA obtained from the sample, and (d) comparing the expression of at least two or more miRNA obtained from the sample tissue with the expression of at least one miRNA obtained from a control sample, wherein a detectable change in the expression of at least two or more miRNA obtained from the sample compared to control is indicative of oncogenic, cancerous, premalignant or metaplastic changes in the gastrointestinal tract of a mammalian subject.
[0012] In accordance with still another embodiment, the present invention provides a method of staging the oncogenic, cancerous, premalignant or metaplastic changes in the esophagus or gastrointestinal tract of a mammalian subject comprising a) obtaining a sample from the subject, b) contacting the RNA from (a) with the array or biochip described above, c) determining the amount of at least two miRNA selected from the group consisting of hsa-miR-200a (SEQ ID NO: 1), hsa-miR-345 (SEQ ID NO: 2), hsa-miR-373 (SEQ ID NO: 3), hsa-miR-630 (SEQ ID NO: 4), hsa-miR-663 (SEQ ID NO: 5), hsa-miR-765 (SEQ ID NO: 6), hsa-miR-625 (SEQ ID NO: 7), hsa-miR-93 (SEQ ID NO: 8), hsa-miR-106b (SEQ ID NO: 9), hsa-miR-155 (SEQ ID NO: 10), hsa-miR-130b (SEQ ID NO: 11), hsa-miR-30a (SEQ ID NO: 12), hsa-miR-301a (SEQ ID NO: 13), hsa-miR-15b (SEQ ID NO: 14), or portions or fragments thereof, or the amount of a precursor molecule of the at least one miRNA, or portions or fragments thereof, in the sample from the subject, d) comparing the amount of the at least two miRNA or the amount of a precursor molecule of the at least two miRNA of a) with at least one or more reference or control amounts, and wherein when a detectable change in the amount of at least two miRNA or portions or fragments thereof, obtained from the sample compared to the reference or control, the stage of the oncogenic, cancerous, premalignant or metaplastic changes in the gastrointestinal tract of a mammalian subject is determined.
[0013] In an embodiment, the present invention provides a method of determining oncogenic, cancerous, premalignant or metaplastic changes the esophagus or gastrointestinal tract of a mammalian subject comprising, (a) extracting miRNA from a sample obtained from a mammalian subject, (b) determining the expression of at least two miRNA obtained from the sample, and (c) comparing the expression of at least two miRNA obtained from the sample tissue with the expression of at least one miRNA obtained from a control sample, wherein a detectable change in the expression of at least one miRNA obtained from the sample compared to control is indicative of oncogenic, cancerous, premalignant or metaplastic changes in the gastrointestinal tract of a mammalian subject.
[0014] In accordance with another embodiment, the present invention provides a method of staging the oncogenic, cancerous, premalignant or metaplastic changes in the esophagus or gastrointestinal tract of a mammalian subject comprising a) obtaining a sample from the subject, b) determining the amount of at least two miRNA selected from the group consisting of hsa-miR-200a, hsa-miR-345, hsa-miR-373, hsa-miR-630, hsa-miR-663, hsa-miR-765, hsa-miR-625, hsa-miR-93, hsa-miR-106b, hsa-miR-155, hsa-miR-130b, hsa-miR-30a, hsa-miR-301a, hsa-miR-15b, or portions or fragments of any of these miRNAs thereof, or the amount of a precursor molecule of the at least two miRNA in the sample from the subject, c) comparing the amount of the at least two miRNA or the amount of a precursor molecule of the at least two miRNA of a) with at least one or more reference or control amounts, and wherein when a detectable change in the amount of at least two miRNA obtained from the sample compared to the reference or control, the stage of the oncogenic, cancerous, premalignant or metaplastic changes in the gastrointestinal tract of a mammalian subject is determined.
[0015] In accordance with a further embodiment, the present invention provides a method for diagnosing the progression the oncogenic, cancerous, premalignant or metaplastic changes in the esophagus or gastrointestinal tract of a mammalian subject comprising a) obtaining a sample from the subject, b) determining the amount of at least two miRNA selected from the group consisting of hsa-miR-200a, hsa-miR-345, hsa-miR-373, hsa-miR-630, hsa-miR-663, hsa-miR-765, hsa-miR-625, hsa-miR-93, hsa-miR-106b, hsa-miR-155, hsa-miR-130b, hsa-miR-30a, hsa-miR-301a, hsa-miR-15b or portions or fragments of any of these miRNAs thereof, or the amount of a precursor molecule of the at least two miRNA in the sample from the subject, c) comparing the amount of the at least two miRNA or the amount of a precursor molecule of the at least two miRNA of a) with at least one or more reference or control amounts, and wherein when a detectable change in the amount of at least two miRNA obtained from the sample compared to the reference or control, the progression of the oncogenic, cancerous, premalignant or metaplastic changes in the gastrointestinal tract of a mammalian subject is determined.
[0016] In accordance with yet another embodiment, the present invention provides a use of at least two miRNA selected from the group consisting hsa-miR-200a, hsa-miR-345, hsa-miR-373, hsa-miR-630, hsa-miR-663, hsa-miR-765, hsa-miR-625, hsa-miR-93, hsa-miR-106b, hsa-miR-155, hsa-miR-130b, hsa-miR-30a, hsa-miR-301a, hsa-miR-15b or portions or fragments of any of these miRNAs thereof, or of a precursor molecule thereof in a sample from a subject suffering from oncogenic, cancerous, premalignant or metaplastic changes in the gastrointestinal tract for identifying a subject being susceptible to gastrointestinal cancer therapy.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] FIG. 1 is a table of miR-array data generated from human samples that was normalized by the array control small RNA called Hurs.
[0018] FIG. 2 is a table of miR-array data generated from human samples that was normalized by Agilent's GeneSpring GX 11.5 software.
[0019] FIG. 3 is a table of miR-array data generated from cell line samples that was normalized by the array control small RNA called Hurs.
DETAILED DESCRIPTION OF THE INVENTION
[0020] By “nucleic acid” as used herein includes “polynucleotide,” “oligonucleotide,” and “nucleic acid molecule,” and generally means a polymer of DNA or RNA, which can be single-stranded or double-stranded, synthesized or obtained (e.g., isolated and/or purified) from natural sources, which can contain natural, non-natural or altered nucleotides, and which can contain a natural, non-natural or altered internucleotide linkage, such as a phosphoroamidate linkage or a phosphorothioate linkage, instead of the phosphodiester found between the nucleotides of an unmodified oligonucleotide. It is generally preferred that the nucleic acid does not comprise any insertions, deletions, inversions, and/or substitutions. However, it may be suitable in some instances, as discussed herein, for the nucleic acid to comprise one or more insertions, deletions, inversions, and/or substitutions.
[0021] In an embodiment, the nucleic acids of the invention are recombinant. As used herein, the term “recombinant” refers to (i) molecules that are constructed outside living cells by joining natural or synthetic nucleic acid segments to nucleic acid molecules that can replicate in a living cell, or (ii) molecules that result from the replication of those described in (i) above. For purposes herein, the replication can be in vitro replication or in vivo replication.
[0022] The nucleic acids used as primers in embodiments of the present invention can be constructed based on chemical synthesis and/or enzymatic ligation reactions using procedures known in the art. See, for example, Sambrook et al. (eds.), Molecular Cloning, A Laboratory Manual, 3rd Edition, Cold Spring Harbor Laboratory Press, New York (2001) and Ausubel et al., Current Protocols in Molecular Biology , Greene Publishing Associates and John Wiley & Sons, NY (1994). For example, a nucleic acid can be chemically synthesized using naturally occurring nucleotides or variously modified nucleotides designed to increase the biological stability of the molecules or to increase the physical stability of the duplex formed upon hybridization (e.g., phosphorothioate derivatives and acridine substituted nucleotides). Examples of modified nucleotides that can be used to generate the nucleic acids include, but are not limited to, 5-fluorouracil, 5-bromouracil, 5-chlorouracil, 5-iodouracil, hypoxanthine, xanthine, 4-acetylcytosine, 5-(carboxyhydroxymethyl) uracil, 5-carboxymethylaminomethyl-2-thiouridine, 5-carboxymethylaminomethyluracil, dihydrouracil, beta-D-galactosylqueosine, inosine, N 6 -isopentenyladenine, 1-methylguanine, 1-methylinosine, 2,2-dimethylguanine, 2-methyladenine, 2-methylguanine, 3-methylcytosine, 5-methylcytosine, N 6 -substituted adenine, 7-methylguanine, 5-methylaminomethyluracil, 5-methoxyaminomethyl-2-thiouracil, beta-D-mannosylqueosine, 5′-methoxycarboxymethyluracil, 5-methoxyuracil, 2-methylthio-N 6 -isopentenyladenine, uracil-5-oxyacetic acid (v), wybutoxosine, pseudouracil, queosine, 2-thiocytosine, 5-methyl-2-thiouracil, 2-thiouracil, 4-thiouracil, 5-methyluracil, uracil-5-oxyacetic acid methylester, 3-(3-amino-3-N-2-carboxypropyl) uracil, and 2,6-diaminopurine. Alternatively, one or more of the nucleic acids of the invention can be purchased from companies, such as Macromolecular Resources (Fort Collins, Co.) and Synthegen (Houston, Tex.).
[0023] The nucleotide sequences used herein are those which hybridize under stringent conditions preferably hybridizes under high stringency conditions. By “high stringency conditions” is meant that the nucleotide sequence specifically hybridizes to a target sequence (the nucleotide sequence of any of the nucleic acids described herein) in an amount that is detectably stronger than non-specific hybridization. High stringency conditions include conditions which would distinguish a polynucleotide with an exact complementary sequence, or one containing only a few scattered mismatches from a random sequence that happened to have a few small regions (e.g., 3-10 bases) that matched the nucleotide sequence. Such small regions of complementarity are more easily melted than a full-length complement of 14-17 or more bases, and high stringency hybridization makes them easily distinguishable. Relatively high stringency conditions would include, for example, low salt and/or high temperature conditions, such as provided by about 0.02-0.1 M NaCl or the equivalent, at temperatures of about 50-70° C.
[0024] The term “isolated and purified” as used herein means a protein that is essentially free of association with other proteins or polypeptides, e.g., as a naturally occurring protein that has been separated from cellular and other contaminants by the use of antibodies or other methods or as a purification product of a recombinant host cell culture.
[0025] The term “biologically active” as used herein means an enzyme or protein having structural, regulatory, or biochemical functions of a naturally occurring molecule.
[0026] As used herein, the term “subject” refers to any mammal, including, but not limited to, mammals of the order Rodentia, such as mice and hamsters, and mammals of the order Logomorpha, such as rabbits. It is preferred that the mammals are from the order Carnivora, including Felines (cats) and Canines (dogs). It is more preferred that the mammals are from the order Artiodactyla, including Bovines (cows) and Swines (pigs) or of the order Perssodactyla, including Equines (horses). It is most preferred that the mammals are of the order Primates, Ceboids, or Simoids (monkeys) or of the order Anthropoids (humans and apes). An especially preferred mammal is the human.
[0027] In accordance with one or more embodiments of the present invention, it will be understood that the types of cancer diagnosis which may be made, using the methods provided herein, is not necessarily limited. For purposes herein, the cancer can be any cancer. As used herein, the term “cancer” is meant any malignant growth or tumor caused by abnormal and uncontrolled cell division that may spread to other parts of the body through the lymphatic system or the blood stream.
[0028] The cancer can be a metastatic cancer or a non-metastatic (e.g., localized) cancer. As used herein, the term “metastatic cancer” refers to a cancer in which cells of the cancer have metastasized, e.g., the cancer is characterized by metastasis of a cancer cells. The metastasis can be regional metastasis or distant metastasis, as described herein.
[0029] The terms “treat,” and “prevent” as well as words stemming therefrom, as used herein, do not necessarily imply 100% or complete treatment or prevention. Rather, there are varying degrees of treatment or prevention of which one of ordinary skill in the art recognizes as having a potential benefit or therapeutic effect. In this respect, the inventive methods can provide any amount of any level of diagnosis, staging, screening, or other patient management, including treatment or prevention of cancer in a mammal. Furthermore, the treatment or prevention provided by the inventive method can include treatment or prevention of one or more conditions or symptoms of the disease, e.g., cancer, being treated or prevented. Also, for purposes herein, “prevention” can encompass delaying the onset of the disease, or a symptom or condition thereof
[0030] “Complement” or “complementary” as used herein to refer to a nucleic acid may mean Watson-Crick (e.g., A-T/U and C-G) or Hoogsteen base pairing between nucleotides or nucleotide analogs of nucleic acid molecules.
[0031] “Differential expression” may mean qualitative or quantitative differences in the temporal and/or cellular gene expression patterns within and among cells and tissue. Thus, a differentially expressed gene may qualitatively have its expression altered, including an activation or inactivation, in, e.g., normal versus disease tissue. Genes may be turned on or turned off in a particular state, relative to another state thus permitting comparison of two or more states. A qualitatively regulated gene may exhibit an expression pattern within a state or cell type which may be detectable by standard techniques. Some genes may be expressed in one state or cell type, but not in both. Alternatively, the difference in expression may be quantitative, e.g., in that expression is modulated, either up-regulated, resulting in an increased amount of transcript, or down-regulated, resulting in a decreased amount of transcript. The degree to which expression differs need only be large enough to quantify via standard characterization techniques such as expression arrays, quantitative reverse transcriptase PCR, northern analysis, and RNase protection.
[0032] “Identical” or “identity” as used herein in the context of two or more nucleic acids or polypeptide sequences may mean that the sequences have a specified percentage of residues that are the same over a specified region. The percentage may be calculated by optimally aligning the two sequences, comparing the two sequences over the specified region, determining the number of positions at which the identical residue occurs in both sequences to yield the number of matched positions, dividing the number of matched positions by the total number of positions in the specified region, and multiplying the result by 100 to yield the percentage of sequence identity. In cases where the two sequences are of different lengths or the alignment produces one or more staggered ends and the specified region of comparison includes only a single sequence, the residues of single sequence are included in the denominator but not the numerator of the calculation. When comparing DNA and RNA, thymine (T) and uracil (U) may be considered equivalent. Identity may be performed manually or by using a computer sequence algorithm such as BLAST or BLAST 2.0.
[0033] “Probe” as used herein may mean an oligonucleotide capable of binding to a target nucleic acid of complementary sequence through one or more types of chemical bonds, usually through complementary base pairing, usually through hydrogen bond formation. Probes may bind target sequences lacking complete complementarity with the probe sequence depending upon the stringency of the hybridization conditions. There may be any number of base pair mismatches which will interfere with hybridization between the target sequence and the single stranded nucleic acids described herein. However, if the number of mutations is so great that no hybridization can occur under even the least stringent of hybridization conditions, the sequence is not a complementary target sequence. A probe may be single stranded or partially single and partially double stranded. The strandedness of the probe is dictated by the structure, composition, and properties of the target sequence. Probes may be directly labeled or indirectly labeled such as with biotin to which a streptavidin complex may later bind.
[0034] “Substantially complementary” used herein may mean that a first sequence is at least 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 97%, 98% or 99% identical to the complement of a second sequence over a region of 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100 or more nucleotides, or that the two sequences hybridize under stringent hybridization conditions.
[0035] “Substantially identical” used herein may mean that a first and second sequence are at least 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 97%, 98% or 99% identical over a region of 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100 or more nucleotides or amino acids, or with respect to nucleic acids, if the first sequence is substantially complementary to the complement of the second sequence.
[0036] “Target” as used herein can mean an oligonucleotide or portions or fragments thereof, which may be bound by one or more probes under stringent hybridization conditions. “Target” as used herein may also mean a specific miRNA or portions or fragments thereof, which may be bound by one or more probes under stringent hybridization conditions.
[0037] In accordance with an embodiment, the present invention provides an array of oligonucleotide probes for identifying miRNAs in a sample, comprising probes that each selectively bind a mature miRNA, and a platform, wherein the probes are immobilized on the platform, wherein at least two probes selectively bind a human miRNA selected from human miRNAs consisting of sequences of SEQ ID NOS: 1-7 and 10-14 or portions or fragments thereof, or at least two probes are selected from probes consisting of sequences of SEQ ID NOS: 1-7 and 10-14, for example, hsa-miR-200a (SEQ ID NO: 1), hsa-miR-345 (SEQ ID NO: 2), hsa-miR-373 (SEQ ID NO: 3), hsa-miR-630 (SEQ ID NO: 4), hsa-miR-663 (SEQ ID NO: 5), hsa-miR-765 (SEQ ID NO: 6), hsa-miR-625 (SEQ ID NO: 7), hsa-miR-155 (SEQ ID NO: 10), hsa-miR-130b (SEQ ID NO: 11), hsa-miR-30a (SEQ ID NO: 12), hsa-miR-301a (SEQ ID NO: 13), hsa-miR-15b (SEQ ID NO: 14) or portions or fragments of any of these miRNAs thereof.
[0038] In another embodiment, the present invention provides an array of oligonucleotide probes for identifying miRNAs in a sample, comprising probes that each selectively bind a mature miRNA, and a platform, wherein the probes are immobilized on the platform, wherein at least three probes selectively bind a human miRNAs consisting of sequences of SEQ ID NOS: 1-7 and 10-14; or at least three probes are selected from probes consisting of sequences of SEQ ID NOS: 1-7 and 10-14. It will be understood by those of ordinary skill that the array can bind any number of oligonucleotide probes, including 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, and 14 probes at one time.
[0039] The nucleic acids of the present invention may also comprise a sequence of a miRNA or a variant thereof The miRNA sequence may comprise from 13-33, 18-24 or 21-23 nucleotides. The miRNA may also comprise a total of at least 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 50, 60, 70, 80, 90 and up to 100 nucleotides. The sequence of the miRNA may be the first 13-33 nucleotides of the pre- miRNA. The sequence of the miRNA may also be the last 13-33 nucleotides of the pre- miRNA. The sequence of the miRNA may comprise the sequence of SEQ ID NOS: 1-14 or portions or fragments thereof
[0040] A probe is also provided comprising a nucleic acid described herein. Probes may be used for screening and diagnostic methods, as outlined below. The probes may be attached or immobilized to a solid substrate or apparatus, such as a biochip.
[0041] The probe may have a length of from 8 to 500, 10 to 100 or 20 to 60 nucleotides. The probe may also have a length of at least 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 35, 40, 45, 50, 60, 70, 80, 90, 100, 120, 140, 160, 180, 200, 220, 240, 260, 280 or 300 nucleotides. The probe may further comprise a linker sequence of from 10-60 nucleotides.
[0042] A biochip is also provided. The biochip is an apparatus which, in certain embodiments, comprises a solid substrate comprising an attached probe or plurality of probes described herein. The probes may be capable of hybridizing to a target sequence under stringent hybridization conditions. The probes may be attached at spatially defined address on the substrate. More than one probe per target sequence may be used, with either overlapping probes or probes to different sections of a particular target sequence. In an embodiment, two or more probes per target sequence are used. The probes may be capable of hybridizing to target sequences associated with a single disorder.
[0043] The probes may be attached to the biochip in a wide variety of ways, as will be appreciated by those in the art. The probes may either be synthesized first, with subsequent attachment to the biochip, or may be directly synthesized on the biochip.
[0044] The solid substrate may be a material that may be modified to contain discrete individual sites appropriate for the attachment or association of the probes and is amenable to at least one detection method. Representative examples of substrates include glass and modified or functionalized glass, plastics (including acrylics, polystyrene and copolymers of styrene and other materials, polypropylene, polyethylene, polybutylene, polyurethanes, Teflon, etc.), polysaccharides, nylon or nitrocellulose, resins, silica or silica-based materials including silicon and modified silicon, carbon, metals, inorganic glasses and plastics. The substrates may allow optical detection without appreciably fluorescing.
[0045] The substrate may be planar, although other configurations of substrates may be used as well. For example, probes may be placed on the inside surface of a tube, for flow-through sample analysis to minimize sample volume. Similarly, the substrate may be flexible, such as a flexible foam, including closed cell foams made of particular plastics.
[0046] The biochip and the probe may be derivatized with chemical functional groups for subsequent attachment of the two. For example, the biochip may be derivatized with a chemical functional group including, but not limited to, amino groups, carboxyl groups, oxo groups or thiol groups. Using these functional groups, the probes may be attached using functional groups on the probes either directly or indirectly using a linkers. The probes may be attached to the solid support by either the 5′ terminus, 3′ terminus, or via an internal nucleotide.
[0047] The probe may also be attached to the solid support non-covalently. For example, biotinylated oligonucleotides can be made, which may bind to surfaces covalently coated with streptavidin, resulting in attachment. Alternatively, probes may be synthesized on the surface using techniques such as photopolymerization and photolithography.
[0048] A method of identifying a nucleic acid associated with a disease or a pathological condition is also provided. The method comprises measuring a level of the nucleic acid in a sample that is different than the level of a control. In accordance with an embodiment, the nucleic acid is a miRNA and the detection may be performed by contacting the sample with a probe or biochip described herein and detecting the amount of hybridization. PCR may be used to amplify nucleic acids in the sample, which may provide higher sensitivity.
[0049] The level of the nucleic acid in the sample may also be compared to a control cell (e.g., a normal cell) to determine whether the nucleic acid is differentially expressed (e.g., overexpressed or underexpressed). The ability to identify miRNAs that are differentially expressed in pathological cells compared to a control can provide high-resolution, high-sensitivity datasets which may be used in the areas of diagnostics, prognostics, therapeutics, drug development, pharmacogenetics, biosensor development, and other related areas.
[0050] The expression level of a disease-associated nucleic acid or miRNA provides information in a number of ways. For example, a differential expression of a disease-associated nucleic acid compared to a control may be used as a diagnostic that a patient suffers from the disease. Expression levels of a disease-associated nucleic acid may also be used to monitor the treatment and disease state of a patient. Furthermore, expression levels of a disease-associated miRNA may allow the screening of drug candidates for altering a particular expression profile or suppressing an expression profile associated with disease.
[0051] A target nucleic acid or portions or fragments thereof, may be detected and levels of the target nucleic acid measured by contacting a sample comprising the target nucleic acid with a biochip comprising an attached probe sufficiently complementary to the target nucleic acid and detecting hybridization to the probe above control levels.
[0052] The target nucleic acid or portions or fragments thereof, may also be detected by immobilizing the nucleic acid to be examined on a solid support such as nylon membranes and hybridizing a labeled probe with the sample. Similarly, the target nucleic or portions or fragments thereof, may also be detected by immobilizing the labeled probe to a solid support and hybridizing a sample comprising a labeled target nucleic acid. Following washing to remove the non-specific hybridization, the label may be detected.
[0053] The target nucleic acid or portions or fragments thereof, may also be detected in situ by contacting permeabilized cells or tissue samples with a labeled probe to allow hybridization with the target nucleic acid. Following washing to remove the non-specifically bound probe, the label may be detected.
[0054] The detection of the target nucleic acid, or portions or fragments thereof, can be through direct hybridization assays or can comprise sandwich assays, which include the use of multiple probes, as is generally known in the art.
[0055] A variety of hybridization conditions may be used, including high, moderate and low stringency conditions as outlined above. The assays may be performed under stringency conditions which allow hybridization of the probe only to the target. Stringency can be controlled by altering a step parameter that is a thermodynamic variable, including, but not limited to, temperature, formamide concentration, salt concentration, chaotropic salt concentration pH, or organic solvent concentration.
[0056] Hybridization reactions may be accomplished in a variety of ways. Components of the reaction may be added simultaneously, or sequentially, in different orders. In addition, the reaction may include a variety of other reagents. These include salts, buffers, neutral proteins, e.g., albumin, detergents, etc. which may be used to facilitate optimal hybridization and detection, and/or reduce non-specific or background interactions. Reagents that otherwise improve the efficiency of the assay, such as protease inhibitors, nuclease inhibitors and anti-microbial agents may also be used as appropriate, depending on the sample preparation methods and purity of the target.
[0057] A kit is also provided comprising an array of oligonucleotides as described herein, or portions or fragments thereof, as well as a biochip as described herein, along with any or all of the following: assay reagents, buffers, probes and/or primers, and sterile saline or another pharmaceutically acceptable emulsion and suspension base. In addition, the kits may include instructional materials containing directions (e.g., protocols) for the practice of the methods described herein.
[0058] In accordance with another embodiment of the present invention, it will be understood that the term “biological sample” or “biological fluid” includes, but is not limited to, any quantity of a substance from a living or formerly living patient or mammal. Such substances include, but are not limited to, blood, serum, plasma, urine, cells, organs, tissues, bone, bone marrow, lymph, lymph nodes, synovial tissue, chondrocytes, synovial macrophages, endothelial cells, and skin. In a preferred embodiment, the fluid is blood or serum.
[0059] A method of diagnosis is also provided. The method comprises detecting a differential expression level of two or more disease-associated miRNAs in a biological sample. The sample may be derived from a subject. Diagnosis of a disease state in a subject may allow for prognosis and selection of therapeutic strategy. Further, the developmental stage of cells may be classified by determining temporarily expressed disease-associated miRNAs.
[0060] In situ hybridization of labeled probes to tissue arrays may be performed. When comparing the levels of miRNA expression between an individual and a standard, the skilled artisan can make a diagnosis, a prognosis, or a prediction based on the findings. It is further understood that the genes which indicate the diagnosis may differ from those which indicate the prognosis and molecular profiling of the condition of the cells may lead to distinctions between responsive or refractory conditions or may be predictive of outcomes.
[0061] In accordance with an embodiment, the present invention provides an array of oligonucleotide probes for identifying miRNAs in a sample, comprising: probes that each selectively bind a mature miRNA; and a platform, wherein the probes are immobilized on the platform; wherein at least one probe selectively binds a human miRNA selected from human miRNAs comprising sequences of SEQ ID NOS: 1-14 or a portion or fragment thereof or at least one probe is selected from probes comprising sequences of SEQ ID NOS: 1-14 or a portion or fragment thereof.
[0062] Exemplary biochips of the present invention include an organized assortment of oligonucleotide probes described above immobilized onto an appropriate platform. Each probe selectively binds a miRNA in a sample. In certain embodiments, each probe of the biochip selectively binds a biologically active mature miRNA in a sample.
[0063] In accordance with another embodiment, the biochip of the present invention can also include one or more positive or negative controls. For example, oligonucleotides with randomized sequences can be used as positive controls, indicating orientation of the biochip based on where they are placed on the biochip, and providing controls for the detection time of the biochip when it is used for detecting miRNAs in a sample.
[0064] Embodiments of the biochip can be made in the following manner. The oligonucleotide probes to be included in the biochip are selected and obtained. The probes can be selected, for example, based on a particular subset of miRNAs of interest. The probes can be synthesized using methods and materials known to those skilled in the art, or they can be synthesized by and obtained from a commercial source, such as GeneScript USA (Piscataway, N.J.).
[0065] Each discrete probe is then attached to an appropriate platform in a discrete location, to provide an organized array of probes. Appropriate platforms include membranes and glass slides. Appropriate membranes include, for example, nylon membranes and nitrocellulose membranes. The probes are attached to the platform using methods and materials known to those skilled in the art. Briefly, the probes can be attached to the platform by synthesizing the probes directly on the platform, or probe-spotting using a contact or non-contact printing system. Probe-spotting can be accomplished using any of several commercially available systems, such as the GeneMachines™ OmniGrid (San Carlos, Calif.).
[0066] The miRNA sample can be amplified and labeled as is appropriate or desired. If amplification is desired, methods known to those skilled in the art can be applied. The miRNA samples can be labeled using various methods known to those skilled in the art. In accordance with an embodiment, the miRNA samples are labeled with digoxigenin using a Digoxigenin (DIG) Nucleotide Tailing Kit (Roche Diagnostics Corporation, Indianapolis, Ind.) in a GeneAmp® PCR System 9700 (Applied Biosystems, Foster City, Calif.).
[0067] The labeled miRNA sample is incubated with the biochip, allowing the miRNAs in the sample to hybridize with a probe specific for the miRNAs in the sample. In certain embodiments, the labeled miRNA sample is added to a DIG Easy Hyb Solution or Hybrid Easy Buffer (Roche Diagnostics Corporation, Indianapolis, Ind.) that has been preheated to hybridization temperature. The miRNA sample is the incubated with the biochip in the solution, for example, for about 4 hours to about 24 hours.
[0068] The miRNAs in the sample can be detected, identified, and quantified in the following manner. After the miRNA sample has been incubated with the biochip for an appropriate time period, the biochip is washed with a series of washing buffers, and then incubated with a blocking buffer. When Digoxigenin (DIG) labeling of the miRNA samples has been used, the biochip is then incubated with an Anti-DIG-AP antibody (Roche Diagnostics Corporation, Indianapolis, Ind.). The biochip is them washed with washing buffer and incubated with detection buffer, for example, for about 5 minutes. NBT/BCIP dye (5-Bromo-4-Chloro-3′-Indolyphosphate p-Toluidine Salt and NBT Nitro-Blue Tetrazolium Chloride) diluted with detection buffer is added to the biochip, which is allowed to develop in the dark, for example, for about 1 hour to about 2 days under humid conditions.
[0069] The biochips are scanned, for example, using an Epson Expression 1680 Scanner (Seiko Epson Corporation, Long Beach, Calif.) at a resolution of about 1500 dpi and 16-bit grayscale. The biochip images are analyzed using Array-Pro Analyzer (Media Cybernetics, Inc., Silver Spring, Md.) software. Because the identity of the miRNA probes on the biochip are known, the sample can be identified as including particular miRNAs when spots of hybridized miRNAs-and-probes are visualized. Additionally, the density of the spots can be obtained and used to quantitate the identified miRNAs in the sample.
[0070] The identity and relative quantity of miRNAs in a sample can be used to provide an miRNA profiles for a particular sample. An miRNA profile for a sample includes information about the identities of miRNAs contained in the sample, quantitative levels of miRNAs contained in the sample, and/or changes in quantitative levels of miRNAs relative to another sample. For example, an miRNA profile for a sample includes information about the identities, quantitative levels, and/or changes in quantitative levels of miRNAs associated a particular cellular type, process, condition of interest, or other cellular state. Such information can be used, for diagnostic purposes, drug development, drug screening and/or drug efficacy testing. In an embodiment, the miRNAs of the present invention are unregulated in subjects having pre-clinical EAC and BE. For example, the presence of these miRNAs in high levels compared with controls indicates a diagnosis of BE or EAC in a subject.
[0071] In another example, with regard to diagnostics, if it is known that the presence or absence of a particular miRNA or group of miRNAs is associated with the presence or absence of a particular condition of interest, then a diagnosis of the condition can be made by obtaining the miRNA profile of a sample taken from a patient being diagnosed.
EXAMPLES
[0072] Tissue Specimens. All patients provided written informed consent under a protocol approved by the Institutional Review Boards at the University of Maryland and Baltimore Veterans Affairs Medical Centers, where all endoscopies were performed. Biopsies were taken using a standardized biopsy protocol. Research tissues were obtained from macroscopically apparent Barrett's epithelium or from mass lesions in patients manifesting these changes at endoscopic examination, and histology was confirmed using parallel aliquots from identical locations obtained at the same endoscopy. All biopsy specimens were stored in liquid nitrogen prior to DNA/RNA extraction.
[0073] miRNA extraction from serum. TRIzol LS Reagent (Invitrogen, cat. no. 15596-018) was used to extract total RNA from sera of 16 patients with EAC, BE or 12 age-matched normal EGD, and 16 tissues each of EAC, BE or 12 age-matched normal EGD. 750 μl of TRIzol LS Reagent was added to 250 μl of serum sample and mixed thoroughly. After 5 minutes of incubation, 200 μl of chloroform is added to the mixture, followed by 3 minutes of incubation. Then, the mixture was centrifuged at 12,000xg for 15 minutes at 4° C. After centrifugation, the upper aqueous layer was transferred into new tubes, and 1.5 volumes of 100% ethanol was added to 1 volume of the aqueous layer. The mixture was then added to RNeasy Mini kit (QIAGEN, cat. no. 74904) columns for the total RNA extraction according to the manufacturer's instructions. 30 μl of RNase-free water was added onto the column to elute the RNA.
[0074] Quantitative RT-PCR (qRT-PCR) is an invaluable tool for highly sensitive and accurate quantitation of miRNA expression, and constitutes the standard method for independently validating microarray data. The application of TaqMan (I RT-PCR technology permits the analysis of mature miRNAs, rather than their precursors, ensuring the biological relevance of miRNA expression.
[0075] Gene Expression Microarrays. Arrays containing 60-mer oligonucleotide probes corresponding to 22,000 genes (Illumina HumanRef-8 Expression BeadChip v2, Illumina, San Diego, Calif.) were used to construct an mRNA expression database for the cell lines studied. 100 ng of total RNA was used for each labeling and hybridization reaction. Data was normalized according to the LOWESS fitting curve method using MATLAB (The MathWorks, Inc., Natick, Mass.).
[0076] MicroRNA Microarrays. MiRNA Labeling Reagent and Hybridization Kits (Agilent, Santa Clara, Calif.) and Agilent's Human miRNA Microarray V1 which contains 471 human miRs, were used to generate global miR expression profiles. This platform is designed to ensure extremely high data fidelity and robustness. Each miR is represented by 30 probes on the array (i.e., 15 replicates of 2 distinct probes hybridize to each miR). Furthermore, these 30 probes are evenly distributed across the array to minimize positional hybridization bias. 100 ng of total RNA from each cell line was phosphatase-treated and then labeled with cyanine 3-pCp. The labeled RNA was purified using Micro Bio-spin columns (BIO-RAD, Hercules, Calif.) and subsequently hybridized to a human miR microarray slide at 55° C. for 20 hours. After hybridization, the slides were washed with Gene Expression Wash Buffer (Agilent) and scanned on an Agilent Microarray Scanner (Agilent) using Agilent's Scan Control, version A. 7.0.1 software. Data was collected and normalized to non-functional small RNA internal controls.
[0077] Statistical Analysis. Results of experiments were displayed as mean ±standard deviation. To evaluate statistical significance, Student's unpaired t test was used, unless otherwise noted.
[0078] Quantitative RT-PCR for miR Expression. TaqMan MicroRNA Assays, Human (Applied Biosystems, Foster City, Calif.) were used to confirm miR expression changes identified on miR microarrays, according to the manufacturer's protocol. qRT-PCR was performed in triplicate. RNU6B (RNU6B TaqMan microRNA Assay kit, Applied Biosystems) was used as an internal control.
Example 1
[0079] MiR microarrays are hybridized to miRs extracted from matching tissues and blood obtained from 16 subjects each with esophageal adenocarcinoma (EAC), and compared to that of 12 healthy subjects.
[0080] In addition to these samples, miRs extracted from various normal esophageal, Barrett's, and EAC cell lines (HEEPiC, CHTRT, GiHTRT, QHTRT, and OE33 from ATCC, Manassas, Va.) were also used. For these experiments, we used QIAGEN's miRNeasy Mini Kit for the actual miR extraction, and Agilent's Human miRNA Microarray V1 which contains 471 human miRs.
Example 2
[0081] MiR-array data generated was normalized either by Agilent's GeneSpring GX 11.5 software or by the array control small RNA called Hurs. The normalized data was analyzed using significance analysis of microarrays (SAM).
[0082] The serum data was first normalized using the Hurs array control ( FIG. 1 ). The top 144 highest fold-change overexpressed miRs were selected that differed by a significant p-value between diseased and normal control (NC). As a final filtering criterion, to ensure that serum miRs will be robustly detectable, miRs were chosen whose individual serum levels uniformly exceeded array background by at least a factor of 5.
[0083] Next, the same data was normalized using GeneSpring GX 11.5 software, which used percentile shift normalization. This procedure generated an initial 7 possible miR candidates ( FIG. 2 ).
Example 3
[0084] The cell line data from various normal esophageal, Barrett's, and EAC cell lines (HEEPiC, CHTRT, GiHTRT, QHTRT, and 0E33) was processed in the same way as the serum data in Example 2. The cell line data SAM result generated 11 possible miR candidates ( FIG. 3 ). We arrived at a selection of 14 miR candidates (hsa-miR-200a, hsa-miR-345, hsa-miR-373*, hsa-miR-630, hsa-miR-663, hsa-miR-765, hsa-miR-625, hsa-miR-93, hsa-miR-106b, hsa-miR-155, hsa-miR-130b, hsa-miR-30a, hsa-miR-301a, hsa-miR-15b) which commonly appeared or significant in 3 separate analysis.
[0085] All references, including publications, patent applications, and patents, cited herein are hereby incorporated by reference to the same extent as if each reference were individually and specifically indicated to be incorporated by reference and were set forth in its entirety herein.
[0086] The use of the terms “a” and “an” and “the” and similar referents in the context of describing the invention (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The terms “comprising,” “having,” “including,” and “containing” are to be construed as open-ended terms (i.e., meaning “including, but not limited to,”) unless otherwise noted. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”) provided herein, is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the invention.
[0087] Preferred embodiments of this invention are described herein, including the best mode known to the inventors for carrying out the invention. Variations of those preferred embodiments may become apparent to those of ordinary skill in the art upon reading the foregoing description. The inventors expect skilled artisans to employ such variations as appropriate, and the inventors intend for the invention to be practiced otherwise than as specifically described herein. Accordingly, this invention includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the invention unless otherwise indicated herein or otherwise clearly contradicted by context. | Robust and reliable molecular diagnostic screening tools for early detection of esophageal and gastrointestinal tract cancers and pre-cancerous lesions, such as Barrett's Esophagus, and esophageal adenocarcinoma are provided. Included in the invention is an array of miRNA probes specific for identifying, diagnosing and prognosticating esophageal and gastrointestinal tract cancers and pre-cancerous lesions in subjects from blood or serum samples. A biochip comprising the array as well as methods for its use are also provided. | 2 |
BACKGROUND OF THE INVENTION
The present invention relates to wire rope and, more particularly, to plastic encapsulated wire rope having spacer strands between its central core strand and surrounding outer strands.
Plastic encapsulated wire rope, such as disclosed in U.S. Pat. No. 3,824,777, has been demonstrated to have properties such as tensile strength, fatigue life and corrosion resistance superior to those of equal size bare wire rope. Such improved properties are derived from the separation of the core strand from the outer strands and the outer strands from each other by the thermoplastic material. Suitable themoplastics include polypropylene, polyurethane, polyethylene, nylon, tetrafluroethylene or polyvinylchloride. Also useful are elastomers such as butyl or nitrile rubber. Such a coating reduces or eliminates such core to strand and strand to strand contact and abrasion when the rope is in service. Further, the coating traps any desired lubricant such as petrolatum within the strands and resists the ingress of abrasive or corrosive elements into the rope.
However, it is desirable to achieve strand gap or interstice balance in the manufacture of such plastic encapsulated wire rope. Such gap balance insures the equal load sharing by the strands of the rope and also assures the spacing between strands is filled with plastic. One method of such gap control during rope manufacture is set forth in U.S. Pat. No. 3,824,777, wherein a strand gap controller die is utilized to equally separate rope strands during the injection of the plastic.
Another spacing control method is disclosed in U.K. patent application No. 2,090,305 A, wherein a filler element of thermoplastic containing a reinforcing core is placed independently in the interstice. The presence of such independent thermoplastic element would prohibit the introduction of a flowable thermoplastic into the wire rope.
It is an object of the present invention to provide an encapsulated wire rope having uniform strand gaps and a method of making such rope.
SUMMARY OF THE INVENTION
The present invention relates to a wire rope having uniform strand separation and interstices and to a method of making such rope.
The rope is comprised of a central core usually comprising strands forming an independent wire rope core (IWRC). Such rope core is surrounded by a plurality of outer strands, each comprised of a plurality of individual wires. As such outer strands are wound around the core, there are gaps or spaces or interstices between such outer strands and the core. As the diameters of the core strand and the outer strands are normally within 25% of each other, those gaps are small. However, it is important for the wear life and other similar properties of the rope that such gaps are as uniform as possible. This insures that during the extrusion of the coating material within the rope that such coating provides a uniform spacing between the core strand and the outer strands and between adjacent outer strands. Accordingly, a spacer strand is placed in each such gap during the closing or rope forming operation. Such spacer strand can take different forms as will be later explained, but the main function of such spacer strand is to insure the uniform gap formation between the outer strands. Further, the spacer strand must be of such a configuration so as to permit the impregnation of the rope after final closing by a coating material such as a themoplastic or an elastomer in an extrusion operation.
To permit the coating to be extruded into the spaces between the core strand and the outer strand, the spacer strands must provide gaps or some other type of passage for the coating material. To insure the uniformity of the spaces between the outer strands, each spacer strand contacts both the core strand and two outer strands. Another way of viewing the preferred arrangement is that each outer strand contacts two spacer strands to assure the positioning and spacing of the outer strand. The spacer strands may take any one of several configurations. A single wire may be wound into a helix arrangement to provide the necessary spacing and coating flow configuration. A single central wire can be surrounded by either one or two helixed wires to again provide the necessary spacing and coating flow configuration. Further, two or three wires may be helically wound to form a rope structure which will provide the necessary spacing and coating flow configuration.
In particular, the present invention provides a wire rope comprising a central core including a plurality of wire strands, a plurality of outer strands surrounding said core, a plurality of spacer strands located in the interstices between said core and said outer strands, and a coating extending from substantially the outer diameter of the outer stands down to and into the central core.
The present invention also provides a method of manufacturing a wire rope comprising the steps of providing a central core strand, winding a plurality of spacer strands about said core strand, winding a plurality of outer strands about said spacer strands and said core strand so as to form evenly dimensioned interstices between said core stand and said outer strands containing said spacer strands, and injecting a coating into said wire rope so as to form a continuous, single element composition between the central core and the outer strands.
With a rope according to the invention it is possible to maintain a series of strand to strand gaps of even dimension which permits the ingress of plastic between the strands through the passageways in the spacer element into the core. The equal strand gaps permit a continuous coating of plastic to be formed to provide a positive bond for the external infilling to the underlaying infilling, thereby preventing the detachment of the external infilling under arduous operating conditions during the periods of continual flexing around smaller than desirable sheaves or drums.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings,
FIG. 1 is a cross sectional view of an encapsulated wire rope made in accordance with the present invention;
FIG. 2 is a cross sectional view of another encapsulated wire rope made in accordance with the present invention;
FIG. 3 is a cross sectional view of another encapsulated wire rope made in accordance with the present invention;
FIG. 4 is a perspective view of one embodiment of a spacer strand;
FIG. 5 is a perspective view of another embodiment of a spacer strand;
FIG. 6 is a perspective view of another embodiment of a spacer strand, and
FIG. 7 is a perspective view of another embodiment of a spacer strand.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to FIG. 1 of the drawings, a wire rope is shown generally at 10. A central core strand 14 comprises several single wires 15 in a wire rope configuration. Core 14 is surrounded by a plurality of outer strands 12, each of which is comprised of several single wires 13 in a wire rope configuration. Spacer strands 16 are present in the interstices between core 14 and outer strands 12. Spacer strands 16 are shown as comprising three wires wound to form a strand. A coating 18 extends from the outer surface of core 14 to the outer diameter limits of outer strands 12. Each spacer strand 16 contacts core 14 and two outer strands 12. Coating 18 usually comprises a thermoplastic, and separate core strand 14 from outer strands 12, as well as outer strands 12 from adjacent outer strands. Coating 18 is uniform and, due to its extruded introduction into rope 10, forms a continuous single element composition.
Referring now to FIG. 2 of the drawings, a wire rope is shown generally at 20. A central core strand 22 is provided and is comprised of a plurality of individual wires 23 in a wire rope configuration. Surrounding core strand 22 are a plurality of intermediate strands 24, each of which is comprised of a plurality of individual wires 25. Spacer strands 26 are located in the interstices between core strand 22 and intermediate strands 24, and spacer strands 9 are located in the interstices between intermediate strands 24 and outer strands 28. Spacer strands 26 and 9 are shown as comprising three wires wound to form a strand. A plurality of outer strands 28 surround intermediate strands 24. Each outer strand 28 is comprised of a plurality of individual wires 29. A coating 30 extends from the outer surface of core 22 to the outer diameter limits of outer strands 28. Each spacer strand 26 contacts core 22 and two intermediate strands 24, and each spacer strand 9 contacts an intermediate strand 24 and an outer strand 28. Coating 30 usually comprises a thermoplastic, and separates core strand 22 from intermediate strands 24, intermediate strands 24 from outer strands 28, intermediate strands 24 from adjacent intermediate strands and outer strands 28 from adjacent outer strands. Coating 30 is uniform and, due to its extruded introduction into rope 20, forms a continuous, single element composition.
Referring now to FIG. 3, a wire rope is shown generally at 32. A central core strand 34 is provided and is comprised of a plurality of individual wires 33. Surrounding core strand 34 are a plurality of intermediate strands 36, each of which is comprised of a plurality of individual wires 35. In the interstices between core strand 34 and intermediate strands 36 are located spacer strands 38. Spacer strands 38 are shown as comprising two wires wound to form a strand. A coating 40 extends from the outer surface of core 34 to the outer diameter limits of intermediate strands 36. Each spacer strand 38 contacts core 34 and two intermediate strands 36. Coating 40 usually comprises a thermoplastic, and separates core strand 34 from intermediate strands 36 and core strands 34 from adjacent core strands and intermediate strands 36 from adjacent intermediate strands. Coating 40 is uniform and, due to its extruded introduction into the rope comprising core strand 34 and intermediate strands 36, forms a continuous, single element composition. A plurality of outer strands 42 each comprising individual wires 39 surround the coated intermediate strands 36.
Referring now to FIGS. 4-7, various embodiments of the spacer strands of the present invention are shown. Normally such spacer strands are of a softer metal than the strands that they separate to avoid notching of the core or outer strands that they separate. In FIG. 4, a spacer strand is shown comprising two individual wires 44 and 46 which are helically wound about each other to form the spacer strand. It is also an embodiment of the present invention to helically wind three wires about each other to form a spacer strand; such an arrangement is shown in cross section in FIGS. 1 and 2.
In FIG. 5, a spacer strand is shown comprising a single wire 48 that is wound into a helix about an imaginary central axis.
In FIG. 6, a spacer strand is shown comprising a center wire 50 about which is wound an outer wire 52.
In FIG. 7, a spacer strand is shown comprising a center wire 54 about which are wound outer wires 56 and 58 in alternating helix arrangement. | A wire rope is provided having a central core strand about which are wound outer strands. Spacer strands are present in the gaps between such core strand and outer strands to assume the uniformity of such gaps. A coating, usually of a suitable thermoplastic, is extruded into such rope to provide a spacer between such core and such outer strands, and between adjacent outer strands. | 3 |
BACKGROUND OF THE INVENTION
This invention relates to a process for removing liquid from thickened sludge by pressing.
Sludge comprising finely divided solids in admixture with a liquid, such as water, is a by-product obtained by many industrial processes. An example of such sludge is lime sludge which is a by-product obtained in the production of sugar.
In may cases the concentration of solids of sludge is relatively low, i.e., from 0.5 to 20% by weight, and in order to permit a satisfactory handling of such sludge it is, therefore, necessary to remove a substantial amount of water therefrom so as to form a thickened sludge.
Various apparatuses are suitable for producing thickened sludge. Examples of such apparatuses are continuous centrifuges, such as decanting centrifuges, belt presses in which the sludge is compressed between two continuously travelling belts and drum filters in which sludge is sucked onto a filter cloth mounted on the exterior surface of a rotating drum by means of a vacuum generated within said drum.
The thickened lime sludge formed by using such apparatuses ordinarily has a concentration of solids of between 15 and 55% by weight. The thickened lime sludge is a plastic mass which is neither liquid nor solid.
However, if subjected to a powerful mechanical treatment, e.g. pumping, the thickened lime sludge may be made flowable and in that condition it may be pumped and transported to sludge dewatering reservoirs. Such sludge containing reservoirs, which occupy large areas, often produce a bad smell because the sluge starts to putrefy during the relatively long periods of time in which the sludge has to remain therein in order to be dewatered.
After storage in such reservoirs, the dewatered lime sludge is removed therefrom and may be utilized as a fertilizer and/or a soil improving material.
It is desirable to remove further amounts of water than possible by storing lime sludge in sludge dewatering reservoirs in order to produce a solid dry product which can be handled in a more convenient manner than the dewatered sludge produced as described above.
It has been attempted to remove water from thickened sludge by pressing, and in a prior art apparatus the thickened sludge is introduced into a cylinder comprising a piston and means for draining off liquid and is compressed therein so as to form a sludge cake.
In practice, however, it has been found that it is very difficult to provide an efficient and stable packing between the piston and the cylinder, i.e., between the high pressure zone and the low pressure zone of such an apparatus.
The main object of the invention is to convert thickened sludge into a low moisture containing material by a process, which does not suffer from the drawbacks of the prior art process.
A further object of the invention is to increase the contration of solids of thickened sludge, e.g., from 15-55% to 20-90% by weight.
SUMMARY OF THE INVENTION
These and other objects and advantages which will appear from the following description are obtained by the process of the invention, which process comprises the steps of
(1) depositing thickened sludge onto a porous support,
(2) partially removing liquid from the thickened sludge by establishing a vacuum within said porous support,
(3) compressing the partially dried sludge on said porous support at a relatively low pressure to remove additional liquid therefrom and to form a sludge cake,
(4) subsequently compressing said sludge cake on said porous support at a relatively high pressure to remove further amounts of liquid therefrom, and
(5) finally discharging the dried sludge cake from said porous support.
Surprisingly it has been found that due to the initial removal of liquid by suction through the porous support and the following compression of the partially dried sludge at a relatively low pressure, the properties of the sludge are changed in a manner such that the sludge cake can be compressed at a relatively high pressure without confining the sludge cake in a chamber which fits closely with the pressure head used for effecting the compression. Thus, it has been found that these initial treatments of the thickened sludge have the effect of making the sludge sufficiently solid to allow the sludge cake formed to be further compressed at a relatively high pressure without flowing out of the pressure zone. Consequently, the process of the invention does not require the use of packing or other sealing means to confine the sludge cake within the pressure zone.
Thus, by using the uncomplicated process of the invention, thickened sludge can be converted into a solid product having a sufficiently low concentration of liquid to allow such products to be handled in the same manner as ordinary dry products. Thus, the product obtained is sufficiently dry to be transported with conveyors ordinarily used for transporting solid materials and to be filled into sacks. Furthermore, the product obtained is capable of being spread on the fields as a fertilizer and/or soil improving material by using ordinary fertilizer distributors.
In a preferred embodiment of the precess of the invention the vacuum established in the porous support during the suction step is maintained during the following compression steps so as to facilitate the removal of liquid pressed out of the sludge.
The removal of liquid from thickened sludge by the process of the invention is preferably carried out by a cyclic process comprising the steps of establishing a vacuum within the porous support, passing the porous support through a bath of thickened sludge while maintaining said vacuum within the porous support so as to deposit at least one layer of thickened sludge on said support, passing the porous support to a compression zone while maintaining said vacuum in said porous support so as to effect a partial removal of liquid from the thickened sludge, compressing the sludge layer on said support at a relatively low pressure so as to form a sludge cake, increasing the pressure to a relatively high value so as to form a dried sludge cake and removing the dried sludge cake from the porous support by establishing a super-atmospheric pressure within said porous support.
After the removal of the dried sludge cake from the porous support, a vacuum may be established within said porous support and the steps described above may be repeated.
The compression of the sludge is preferably effected at pressures with the range of from 1 to 300 kp/cm 2 and most preferred from 10 to 300 kp/cm 2 .
The invention also relates to an apparatus for carrying out the process described above.
The apparatus of the invention comprises a porous support connectable to a vacuum source, means for depositing thickened sludge onto said porous support, a pressure head for pressing thickened sludge against said porous support at increasing pressures so as to obtain a dried sludge cake and means for removing the dried sludge cake from said porous support.
A preferred embodiment of the apparatus of the invention further comprises a frame member and means for introducing said frame member on the porous support prior to the compression step and for removing said frame member from the porous support before the removal of the dried sludge cake therefrom.
This frame member merely serves to prevent liquid pressed out of the sludge from flowing out of the pressure zone and to guide such liquid into the porous support from which it is removed by suction.
A particularly preferred embodiment of the apparatus of the invention comprises a plurality of double-sided porous supports mounted on a common rotatable shaft, a container located below said rotatable shaft, means for introducing thickened sludge into said container, means for rotating said shaft so as to successively move said porous supports through a circular path passing through said container, a compression zone and a sludge cake discharge zone, means for creating a vacuum in said porous supports during their movement through said container and towards and into said compression zone, means for compressing thickened sludge deposited on said porous support in said compression zone and means for discharging sludge cakes from said porous supports in said sludge cake discharge zone.
By using such an apparatus, the removal of liquid from thickened sludge may be effected in a cyclic semi-continuous manner. Thus, when the sludge cakes have been removed from the porous support, the latter can be reintroduced in the container holding thickened sludge, and the whole process may be repeated.
The porous supports used in the process and the apparatus of the invention preferably comprise a hollow circular flat member having a plurality of passages commumicating with the surfaces of said hollow member. The surfaces of said hollow member are preferably covered by filter discs and a layer of porous material coated on the exterior side by a filter cloth.
In order to facilitate the removal of water from the sludge, the pressure heads may also be provided with a filter disc covered by a layer of porous material and filter cloth and passage communicating with the backside of said filter disc. These passages are preferably connected to means permitting a vacuum or a super-atmospheric pressure to be established within the pressure head.
The process and the apparatus of the invention are suitable for drying a wide range of sludge products produced in various industries and production plants, such as lime sludge produced in the sugar industry and yeast sludge obtained in bakeries. Further, the process and the apparatus of the invention may be used for drying similar products obtained in the cement industry, porcelain industry, kaolin production plants, plants for chemical and biological purification of waste products, wood and cellulose industry, the ceramic industry and the mining industry.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 schematically illustrates an embodiment of an apparatus of the invention,
FIG. 2 shows a cross-sectional view of a compression station of the apparatus shown in FIG. 1, and
FIG. 3 shows a cross-sectional view of a preferred embodiment of a porous support and cooperating pressure heads of an apparatus according to the invention, the left side of FIG. 3 showing the positions of the pressure head, frame member and porous support before the compression of the sludge and the right side of the drawing showing the positions of these components during the compression of the sludge. It should be mentioned, however, that in practice the compression takes place simultaneously on both sides of the porous support.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The apparatus illustrated in FIG. 1 comprises a hollow shaft 1 mounted for rotation about a horizontal axis in the direction indicated by an arrow 2. A vacuum conduit (not shown) and a compressed air conduit (not shown) are mounted within the shaft 1. The shaft 1 is surrounded by a manifold 3, which is supporting eight hollow arms 4, each carrying at its outer end a filter element 5a - 5f. These filter elements may be of the type shown in FIG. 3. The manifold 3 is constructed in a manner so that the hollow arms 4 can be connected with the vacuum conduit and the compressed air conduit, respectively, or be closed relative to said conduits depending on the position of the filter elements 5a - 5f.
In the positions illustrated in FIG. 1, the arms 4 of the filter elements 5a - 5d and 5g - 5h are connected with the vacuum conduit, whereas the arms of the filter elements 5e and 5f are closed relative to the vacuum and compressed air conduits. During the movement of the filter elements between the positions corresponding to filter elements 5d and 5e, the filter element is connected with the compressed air conduit for a short time.
A container 6 is located below the assembly of filter elements so that the filter elements during their rotation pass through said container. The container 6 is adapted to hold a bath 7 of thickened sludge, which is to be converted into dry sludge cakes. The container 6 is connected with a pump 8 for supplying thickened sludge to the container. The container 6 further comprises an overflow pipe 9 terminating above a funnel 10 which communicates with the pump 8. This system permits the thickened sludge contained in the container 6 to be continuously circulated.
The apparatus also comprises a compression station 11 which is illustrated in detail in FIG. 2 as well as two trays 12 which are spaced apart so as to allow the filter elements to pass between said trays 12 during the rotation of the assembly of filter elements. The outer edges of the trays 12 terminate outside the apparatus and may be associated with means (not shown) for removing dried sludge cakes.
The compression station 11 illustrated in FIG. 2 comprises a U-shaped metal yoke 20 comprising two high pressure cylinders 21. The yoke 20 also comprises four hydraulic cylinders 22. A high pressure piston 23 is mounted in each cylinder 21, and a hydraulic piston 24 is mounted in each hydraulic cylinder 22. Each pressure piston 23 is connected with a press head 25, and each set of hydraulic pistons 24 located adjacent to a high pressure piston 23 is connected to an annular frame member 26. In the position of the assembly of filter elements shown in FIG. 2, a filter element 5 mounted on a hollow arm 4 is located between the two press heads 25, and a sludge layer 27 is confined in the space between each press head 25 and the adjacent surface of the filter element.
The apparatus illustrated in FIGS. 1-2 operates in the following manner:
During the rotation of the filter elements through the bath 7 of thickened sludge contained in the container 6, thickened sludge is sucked onto the surfaces on said filter elements 5 as a result of the vacuum maintained within said filter elements. The thickness of the sludge layer may be between 5 and 100 mm, when the filter elements 5 and the sludge layers deposited thereon move out of the sludge bath 7. The sludge layers are caused to adhere to the filter elements during the movement towards the compression station due to the vacuum maintained within said filter elements. When a filter element reaches the compression station 11, the rotation is stopped. The hydraulic cylinders 22 are then activated so as to bring the annular frame members 26 in contact with the edge portions of the filter element 5. Subsequently, the high pressure cylinders 21 are activated so as to cause the press heads 25 to move synchronously towards the filter element 5 and to exert a pressure on the sludge layers adhering to said filter element. The pressure exerted is gradually increased to a predetermined maximum value. Due to the vacuum maintained within the filter element 5, liquid pressed out of the sludge layers is removed through the hollow arm 4.
Finally, the hydraulic pistons 24 and the high pressure pistons 23 are caused to withdraw.
The assembly of filter elements 5 is then rotated (360/8) = 45° and during said movement the filter element moving from the compression station towards the trays 12 is connected with the compressed air conduit so as to produce a super-atmospheric pressure within the filter element and to disengage the dried sludge cakes from the filter element. These dried sludge cakes fall unto the trays 12 and are then removed.
The filter element illustrated in FIG. 3 comprises a circular core element 31 made from a plastics material or another light-weight material. The core member 31 has a bore 32 which through passages 33 is connected to a series of concentric grooves 34 provided in the surfaces of the core member 31. Each groove surface of the core member 31 is covered by a filter disc 35 coated with a layer of a porous material, which in turn is covered by a filter cloth 37.
The press heads 25 also comprises a combination of a filter disc 38, a layer 39 of a porous material and a filter cloth 40. Furthermore, the pressure heads 25 are provided with passages 41 which can be connected with a vacuum source and a source of compressed air, respectively.
The frame members 26 which are supported by piston rods 42 have front faces 43 which are adapted to engage with the peripheral edge of the filter element so as to align the filter element with the pressure head during the compression of the sludge layer 27.
During the initial portion of the compression of the sludge layers 27, the pressure heads are pressed against said layers at a pressure of the order of 1-10 kp/cm 2 so as to partially dewater the sludge layers. The water pressed out of the sludge layers is removed through the bore 32 and the passages 41.
During this initial compression the structure of the sludge layer changes and the initial plastic mass which tends to flow when strongly compressed becomes a solid rigid cake. When the pressure subsequently is increased from 1-10 kp/cm 2 to 30-300 kp/cm 2 , additional water is removed and a dry solid coherent cake is obtained.
The compression may be effected with a press head which does not fit closely to the wall member, and the distance between the periphery of the press head and the wall member may even be up to 5 mm without risking that substantial amounts of the sludge cake are pressed into said space. | Process for dewatering thickened sludge comprising the steps of depositing thickened sludge onto a porous support, partially dewatering the thickened sludge by establishing a vacuum within said porous support, compressing the partially dewatered sludge on said porous support at a pressure of from 1 to 10 kp/cm 2 to further dewater the sludge and to form a sludge cake, compressing the sludge cake on the porous support at a pressure of from 10 to 300 kp/cm 2 to further dewater the sludge cake and discharging the dewatered sludge cake from the porous support. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates generally to semiconductor devices, and more particularly to bipolar junction transistors.
2. Description of the Prior Art
As known in the art, bipolar junction transistors (BJTs), which can be formed using a CMOS compatible process, are key parts of analog integrated circuits such as band-gap voltage reference circuits. These circuits are often sensitive to Vbe (base-emitter voltage) value and Vbe mismatch of BJT.
Unfortunately, the prior art CMOS process compatible BJT structure is not able to control Vbe value and the Vbe mismatch characteristic is unsatisfactory due to salicide non-uniformity that typically occurs at the edge of the active region. The salicide is formed in the active region to reduce the contact resistance. It has been found that salicide encroachment at the edge of the active region causes P + /N well junction leakage, thus leading to worse Vbe mismatch performance. One approach to improve salicide non-uniformity is to reduce cobalt thickness during the salicide formation. However, this approach adversely affects resistance for non-salicide resistors.
Therefore, there is a need in the industry to provide an improved structure of bipolar junction transistors, which is able to control Vbe value of the BJT and provide reduced Vbe mismatch.
SUMMARY OF THE INVENTION
It is one objective of the invention to provide an improved structure of bipolar junction transistors, which is able to control Vbe value of the BJT and provide reduced Vbe mismatch.
From one aspect, in accordance with one embodiment, the present invention provides a bipolar junction transistor including an emitter region; a base region; a first isolation between the emitter region and the base region; a gate on the first isolation region and overlapping at least a portion of a periphery of the emitter region; a collector region; and a second isolation between the base region and the collector region.
From another aspect, in accordance with another embodiment, the present invention provides a bipolar junction transistor including an emitter region; a base region; a first isolation between the emitter region and the base region; a gate on the first isolation region, wherein a sidewall spacer of the gate fills into a recess between the first isolation and the emitter region; a collector region; and a second isolation between the base region and the collector region.
These and other objectives of the present invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment that is illustrated in the various figures and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention. In the drawings:
FIG. 1 is an exemplary layout diagram of a substantially concentric PNP bipolar junction transistor according to one embodiment of the invention;
FIG. 2 is a schematic, cross-sectional view of the PNP bipolar junction transistor in FIG. 1 , taken along line I-I′ of FIG. 1 ; and
FIG. 3 is a schematic, cross-sectional view of a PNP bipolar junction transistor in accordance with another embodiment of this invention.
It should be noted that all the figures are diagrammatic. Relative dimensions and proportions of parts of the drawings have been shown exaggerated or reduced in size, for the sake of clarity and convenience in the drawings. The same reference signs are generally used to refer to corresponding or similar features in modified and different embodiments.
DETAILED DESCRIPTION
The structure and layout of the present invention bipolar junction transistor (BJT) are described in detail. The improved BJT structure is described for a lateral PNP bipolar junction transistor, but it should be understood by those skilled in the art that by changing the polarity of the conductive dopants lateral NPN bipolar junction transistors can be made.
Please refer to FIG. 1 and FIG. 2 . FIG. 1 is an exemplary layout diagram of a substantially concentric PNP bipolar junction transistor 1 according to one embodiment of the invention. FIG. 2 is a schematic, cross-sectional view of the PNP bipolar junction transistor in FIG. 1 , taken along line I-I′ of FIG. 1 . As shown in FIG. 1 and FIG. 2 , the PNP bipolar junction transistor 1 can be formed in a semiconductor substrate 10 such as a P type doped silicon substrate. The PNP bipolar transistor 1 comprises a P + doping region 101 that functions as an emitter region of the PNP bipolar transistor 1 , which can be formed within an N well 14 . The rectangular shape of the emitter region 101 as set forth in FIG. 1 is merely exemplary. The contour of the emitter region 101 is indicated by dashed line.
An N + doping region such as an annular N + doping region 102 that functions as a base region of the PNP bipolar junction transistor 1 can be disposed about at least a portion of a periphery of the emitter region 101 . The rectangular shape of the N + doping region 102 as set forth in FIG. 1 is merely exemplary. An isolation region, such as an annular shallow trench isolation (STI) region 202 can be disposed between the emitter region 101 and the base region 102 . According to the embodiment of this invention, the emitter region 101 , the base region 102 and the isolation region 202 can be formed within the N well 14 .
A P + doping region such as an annular P + doping region 103 that functions as a collector region of the PNP bipolar junction transistor 1 can be disposed about at least a portion of a periphery of the base region 102 . Likewise, the rectangular shape of the P + doping region 103 as set forth in FIG. 1 is merely exemplary. An isolation region such as an annular STI region 204 can be disposed between the collector region 103 and the base region 102 . The isolation region 202 can be spaced apart and physically separated from the isolation region 204 .
A gate such as a continuous, annular polysilicon gate 104 can be provided on the isolation region 202 and overlaps with at least a portion of a periphery the emitter region 101 . The gate 104 may surround the emitter region 101 . According to the embodiment of this invention, the gate 104 may function as a Vbe (base-emitter voltage) control gate. According to the embodiment of this invention, a voltage can be applied on the gate 104 to change the characteristics of the PNP bipolar transistor 1 . For example, a negative gate voltage can be applied to the gate 104 to lower the Vbe of the PNP bipolar transistor 1 and thus lower the breakdown voltage of the PNP bipolar transistor 1 . That is at least because a negative gate voltage applied to the gate 104 can help accumulate hole at the edge between the isolation region 202 and the emitter region 101 and thus result in a more abrupt junction. For an NPN bipolar transistor, a positive gate voltage can be applied to the gate to lower the breakdown voltage. However, according to another embodiment of this invention, the gate 104 may be electrically floating and/or no gate voltage is applied to the gate 104 . According to the embodiment of this invention, the gate 104 may be a P + doped polysilicon gate. For an NPN BJT, the gate may be an N + doped polysilicon gate.
To reduce contact resistance, an emitter salicide layer 301 such as cobalt salicide or the like can be formed on at least a portion of the emitter region 101 that is not covered by the gate 104 . In this embodiment, the emitter salicide layer 301 is not formed in the recess 310 between the isolation 202 and the emitter region 101 , for example, between the inner edge of the isolation region 202 and the emitter region 101 . Since the recess 310 is blocked with the gate 104 during the salicide formation process, the salicide encroachment at the edge of the active region can be alleviated for the emitter region 101 . The P+ region 101 /N-well 14 junction leakage can be reduced by alleviating the salicide encroachment, and thereby a PNP bipolar junction transistor 1 with reduced Vbe mismatch is provided. According to the embodiment of this invention, a base salicide layer 302 such as cobalt salicide or the like can be formed on at least a portion of the base region 102 . According to the embodiment of this invention, a collector salicide layer 303 such as cobalt salicide or the like can be formed on at least a portion of the collector region 103 .
According to the embodiment of this invention, a gate dielectric layer 401 such as silicon dioxide can be formed in the recess 310 between a polysilicon layer 402 of the gate 104 and the emitter region 101 . The gate 104 may further comprise a salicide layer 403 on the polysilicon layer 402 and at least one sidewall spacer 404 .
FIG. 3 is a schematic, cross-sectional view of a PNP bipolar junction transistor 1 a in accordance with another embodiment of this invention, wherein like numeral numbers designate like regions, layers or elements. As shown in FIG. 3 , likewise, the PNP bipolar junction transistor 1 a can be formed in a semiconductor substrate 10 such as a P type doped silicon substrate. The PNP bipolar transistor 1 a comprises a P + doping region 101 that functions as an emitter region of the PNP bipolar transistor 1 a , which can be formed within an N well 14 .
An N + doping region such as an annular N + doping region 102 that functions as a base region of the PNP bipolar junction transistor 1 a can be disposed about at least a portion of a periphery of the emitter region 101 . An isolation region such as a STI region 202 can be disposed between the emitter region 101 and the base region 102 . According to the embodiment of this invention, the emitter region 101 , the base region 102 and the isolation region 202 can be formed within the N well 14 . A P + doping region such as an annular P + doping region 103 that functions as a collector region of the PNP bipolar junction transistor 1 a can be disposed about at least a portion of a periphery of the base region 102 . An isolation region such as an annular STI region 204 can be disposed between the collector region 103 and the base region 102 . The isolation region 202 can be spaced apart and physically separated from the isolation region 204 .
A gate such as a continuous, annular polysilicon gate 104 can be provided on the isolation region 202 . In this embodiment, a sidewall spacer 404 a of the gate 104 fills into a recess 310 between the isolation region 202 and the emitter region 101 . The gate 104 may surround the emitter region 101 . According to the embodiment of this invention, the gate 104 may function as a Vbe control gate. According to the embodiment of this invention, a voltage can be applied on the gate 104 to change the characteristics of the PNP bipolar transistor 1 a . For example, a negative gate voltage can be applied to the gate 104 to lower the Vbe of the PNP bipolar transistor 1 a and thus lower the breakdown voltage of the PNP bipolar transistor 1 a . That is at least because a negative gate voltage applied to the gate 104 can help accumulate hole at the edge between the isolation region 202 and the emitter region 101 and thus result in a more abrupt junction. For an NPN bipolar transistor, a positive gate voltage can be applied to the gate to lower the breakdown voltage. However, according to another embodiment of this invention, the gate 104 may be electrically floating and/or no voltage is applied to the gate 104 . According to the embodiment of this invention, the gate 104 may be a P + doped polysilicon gate. For an NPN BJT, the gate may be an N + doped polysilicon gate.
To reduce contact resistance, an emitter salicide layer 301 such as cobalt salicide or the like can be formed on at least a portion of the emitter region 101 that is not covered by the gate 104 . In this embodiment, the emitter salicide layer 301 is not formed in the recess 310 between the isolation region 202 and the emitter region 101 , for example, between the inner edge of the isolation region 202 and the emitter region 101 . Since the recess 310 is blocked with the gate 104 during the salicide formation process, the salicide encroachment at the edge of the active region can be alleviated for the emitter region 101 . The P+ region 101 /N-well 14 junction leakage can be reduced by alleviating the salicide encroachment, and thereby a PNP bipolar junction transistor 1 a with reduced Vbe mismatch is provided. According to the embodiment of this invention, a base salicide layer 302 such as cobalt salicide or the like can be formed on the at least a portion of base region 102 . According to the embodiment of this invention, a collector salicide layer 303 such as cobalt salicide or the like can be formed on at least a portion of the collector region 103 .
According to the embodiment of this invention, the recess 310 between the isolation region 202 and the emitter region 101 is filled with the spacer 404 a on the inner sidewall of the gate 104 . The polysilicon layer 402 of the gate 104 can be formed on the isolation 202 and the polysilicon layer 402 may not overlap with the emitter region 101 . In this case, there may not be gate dielectric layer formed in the recess 310 .
The BJT provided in the embodiments can be CMOS process compatible parasitic bipolar junction transistors, and is capable of controlling Vbe value of the BJT and/or providing reduced Vbe mismatch.
Those skilled in the art will readily observe that numerous modifications and alterations of the device and method may be made while retaining the teachings of the invention. | In accordance with one embodiment, the present invention provides a bipolar junction transistor including an emitter region; a base region; a first isolation between the emitter region and the base region; a gate on the first isolation region and overlapping at least a portion of a periphery of the emitter region; a collector region; and a second isolation between the base region and the collector region. | 7 |
RELATED APPLICATIONS
[0001] This is a continuation-in-part application of prior filed and currently pending applications having Ser. Nos. 09/909,451 and 10/302,397 and having official filing dates of Jul. 18, 2001 and Nov. 22, 2002 respectfully.
BACKGROUND OF THE INVENTION
INCORPORATION BY REFERENCE
[0002] Applicant(s) hereby incorporate herein by reference, any and all U.S. patents, U.S. patent applications, and other documents and printed matter cited or referred to in this application.
[0003] 1. Field of the Invention
[0004] This invention relates generally to plaster crown molding systems and more particularly to such a system having a nested foundation beam for improved support, and to a method for mounting such a combination.
[0005] 2. Description of Related Art
[0006] The following art defines the present state of this field:
[0007] Minidis, U.S. D424,709 describes a cove base design.
[0008] Roberts, U.S. Pat. No. 4,600,975 describes an indirect lighting assembly consisting of a housing structure and low voltage light tubing for retention therein, said housing structure being a unitarily extruded body having an anchor tab portion extending perpendicularly into a spacer portion and terminating in a light tube housing portion having an open area directing light generally perpendicular to the plane of said spacer portion.
[0009] Azzar et al., U.S. Pat. No. 5,157,886 describes an extruded, thermoplastic baseboard elastomeric molding strip having opposed generally flat front and rear surfaces is provided with a plurality of closely vertically, spaced horizontal, parallel ribs projecting outwardly of the flat front surface over the full surface area thereof. The strip is formed of front and rear surface layers of thermoplastic material of the same durometer hardness with the front surface layer forming at least the tips of the front surface ribs being of a low density thermoplastic material and the balance of the strip being of high density thermoplastic material. The front and rear surface layers may be of contrasting colors. The rear surface of the strip is preferably formed with concave grooves separated by a multiplicity of fine, vertically spaced horizontal, parallel rearwardly projecting ribs with a rear, center rib between adjacent fine ribs, of a larger diameter than adjacent fine ribs separating the rear surface grooves. The rear surface configuration facilitates removing of excess wet adhesive and maintenance of flush adhesive mounting of the molding strip to a building vertical wall.
[0010] Logan et al., U.S. Pat. No. 5,457,923 describes a decorative molding for a corner formed by a ceiling and a vertical wall comprising a thin strip of flexible plastic and is secured to the wall by an attachment allowing the molding strip along its upper and lower edges to be flexible to conform with uneven surfaces in the ceiling and/or wall. In one form the strip is attached to the wall by an adhesive. In another form, a wall track and clip arrangement is utilized to provide easy removal from the wall for paint or wallpaper application. A corner element is provided in one form in which ends of the strips are adhesively secured thereto in overlapping engagement. In another embodiment, the strips are telescopically connected to the corner element.
[0011] Pelosi, Jr. et al., U.S. Pat. No. 5,553,431 describes a fabricated structural beam including at least one longitudinally folded member having a web portion and a head portion. In different embodiments, a plurality of folded members may be interleaved with one another to provide configurations of varying load carrying capabilities. In all cases, the folded head portion is made rigid by forming it into a tube that is closed on all sides.
[0012] Brabant, U.S. Pat. No. 5,651,224 describes an architectural molding assembly comprising of straight molding pieces having a decorative outer surface and a channel in the rear surface thereof. A wall attaching plate is slidingly secured in the channel and has a slot or an aperture therein to engage with a fastener which is secured to a wall. The fastener may be in the form of a screw or a clamp having a projecting finger. When the attaching plates are engaged by the fasteners they are urged against the wall and maintained there under tension. No nail is inserted in the molding and molding connecting pieces and accordingly the assembly can be easily dismantled and remounted when desired.
[0013] Brooks, U.S. Pat. No. 5,823,655 describes a decorative lighting trim system comprising an assemblage of architectural moldings having a viewable surface which is structured to simulate an architectural trim or molding. The architectural molding is configured to retain lights, and to retain and conceal interconnecting electrical wiring to electrify the lights, in a manner which permits the attachment of the architectural moldings to a building surface. Because the architectural moldings are constructed to appear like conventional trims or moldings, the lighting system is virtually inconspicuous when attached to a house, building or other architectural structure, such as a fence or garage. The architectural moldings are in modular sections having varying selected lengths which allow the user to select the appropriate number and length of modular sections to extend along a given building surface, such as an eave, gable or window. The modular architectural molding assemblage is designed to be affixed relatively permanently to a building to eliminate the need for yearly seasonal hanging of lighting trim.
[0014] Richter, U.S. Pat. No. 1,249,500 describes the combination of interior illumination with the walls of a room, of a removably light confining trough involving a supporting body structure designed to contact with and be securely fastened to the said walls, the lower portion of said body having provided with a ledge; suitable brace members secured to said body above the ledge; a radially disposed member consisting the exposed wall of the trough, which radial member is supported by the said brace members and aforesaid ledge; and lighting means concealed from view with the trough.
[0015] Goodhouse, U.S. Pat. No. 1,780,125 describes a fixture for indirect illumination, a moulding strip including a fixed section constituting a supporting and reflecting means for the source of illumination and a movable section for protecting and concealing the source of illumination and interengageable means of connection provided respectively on said sections, said fixed section having a strenghening flange, projecting outwardly therefrom and disposed at an angle with an outer portion of the movable section with which it engages for strengthening and supporting purposes.
[0016] McCutcheon, U.S. Pat. No. 1,917,139 describes a new article of manufacture, a base tile comprising an upright body having its lower portion provided with a downwardly inclined lateral extension the end of which is formed with a transverse rabbet extending the entire width of the tile and opening through the top and front face of said extension to provide an open seat for floor surfacing material and an abutment at the end of the extension for engagement with a floor substructure, the walls of the rabbet being disposed at substantially right angles to each other and defining upper and lower straight edges, one of which indicates the level of the floor surfacing material and the other the level of the floor substructure.
[0017] Filsinger, U.S. Pat. No. 3,309,832 describes a ceramic trim element adapted for multi-purpose use in wail structures employing a plurality of ceramic tile assembled in a pattern, comprising: a ceramic body member including: a main body portion of uniform width having a front glazed surface, a glazed edge face, and a back unglazed surface; said main body portion having adjacent said glazed edge face a longitudinal edge section of reduced thickness providing a longitudinally extending front surface recess; and a leg portion projecting from the back surface of the main body portion at the edge opposite the reduced edge section and generally normal thereto, said leg portion having uniform width for the length of the main body portion and having an outer glazed surface merging with the outer glazed surface of the main body portion, a glazed edge face and a sloping unglazed back face merging with the back unglazed surface of the main body portion.
[0018] Juntunen, U.S. Pat. No. 5,199,237 describes a decorative receptacle covering and providing the appearance of a finished joint between the adjacent rough cut ends of two lineal moldings. The receptacle slidably receives the ends of the lineal moldings, covers the ends and allows cutting the moldings to a rough length and rough end cut, thereby reducing or eliminating the need for precision carpentry skills by one installing the moldings. Receptacles can be made for a wide variety of decorative moldings including casing moldings, base moldings, chair rail moldings, and crown moldings.
[0019] Kanarek, U.S. Pat. No. 5,226,724 describes a modular, fluorescent, indirect lighting system which may be easily mounted to most surfaces by the user, without any technical knowledge or experience, using just a screwdriver and measuring tape. The system is comprised of a family of plug-in modules, each of which contain an integral power bus, that provides power continuity to the adjacent module, and a gender conversion plug that allows the installer to configure each module so that power is supplied only from female connectors. The system includes a power source module and three sizes of illumination modules, which house single 20, 30 or 40 watt lamps, as well as inside and outside corner modules and both straight and corner adjustable-length modules. Modules selected from this family can be plugged together to create a cove lighting system for a room of almost any size or shape. The complete installation is powered by a neat line cord plugged into a standard wall outlet. And, each module can accommodate a continuous decorative facing strip that both enhances the appearance and conceals the modular nature of the system.
[0020] Singhal, U.S. Pat. No. 5,287,667 describes a tile for waterproofing the juncture of a tiled surface and a non tiled surface such as a tub and tile juncture by use of a water proof tile. The waterproof tile consists of a glazed tile surface having a curvature which directs the water away from the juncture, a non glazed surface which is cemented to the tiled wall and a bottom side which holds sealant for sealing against the non tiled surface.
[0021] Fulton, U.S. Pat. No. 5,359,817 describes trim moldings such as crown molding, chair rail molding, base molding and door casing for a building. The trim moldings are made of substantially acrylic or polyester rigid thermoset polymer components. The trim moldings may be manufactured to realistically visually simulate moldings made of natural stone. A method of manufacture of the moldings may utilizes bulk slabs or blocks of rigid thermoset polymer based materials which are then properly shaped for use as a building trim molding with mechanical material removal methods such as sawing, cutting, sanding, and polishing to achieve the desired size, shape and appearance of molding. The thermoset polymer based moldings are structured with grooves in the backside, with the grooves sized and positioned to snap onto spring biased members of mounting fixtures attached to the building for a removable attachment of the moldings.
[0022] Wu, U.S. Pat. No. 5,694,726 describes a plastic plate assembly used in fitting including a flat and linear retainer plate and a casing having curved surfaces. The retainer plate has an L-shaped retaining strip bending inwardly from either lateral side thereof. Correspondingly, the casing has an L-shaped retaining strip bending outwardly from either lateral side thereof for fitting onto the L-shaped retaining strip. The casing further has one of the lateral sides extending to form a soft extension strip at an end portion thereof. The retainer plate is mounted on the wall first and the casing is secured thereto by means of its L-shaped retaining strips fitting into the L-shaped retaining strips of the retainer plate, with the soft extension strip lying close against the wall to conceal any gaps between the casing and the wall.
[0023] Hahn, U.S. Pat. No. 6,228,507 describes a prefabricated crown molding strip designed to facilitate one-person installation and composed of plaster that is reinforced by two layers of fiber reinforcement, one of bulk fiberglass intermixed throughout the outer portion of the strip and the ornamentation thereon and a second of a sheet of fiberglass netting generally centrally located as a spine in the strip and substantially coextensive therewith. Two side surfaces of the strip are disposed generally in perpendicular planes for engagement with a wall and a ceiling, and have patterns of longitudinally extending ribs and grooves of predetermined depths for facilitating adhesive mounting of the strip, and also facilitating selective removal of plaster to accommodate irregularities on supporting surfaces. Pre-formed nail holes are molded in preselected nailing locations. Also the method of making crown molding strips in steps providing the above characteristics, in a sequence of pours of plaster in fluid state, the addition of the reinforcing fiber, and formation of the patterns of ribs and grooves.
[0024] Boomer, U.S. 2001/0045076 A1, describes a building component that is in the form of an elongate prefabricated cornice to be used in lengths around the top of a wall or walls or a room. The cornice has a mounting part and a facing part. The mounting part has a cross-section with two legs at an angle to each other. The outer edge of each leg terminates in a reflexive bend with the outer portion of the bends inwardly directed. The facing part is a strap of material capable of being snap-fitted into or slid along the mounting part with the inside of each bend serving as a seat to receive a longitudinal edge of the facing part. A corner-piece is provided to join two adjacent lengths of cornice at a corner, the corner-piece being in two parts having a wall-mountable angle bracket and a correspondingly angled cornice part to be secured thereto.
[0025] Stovax Limited, GB 2274860 describes a cornice that is formed of a series of similar ceramic elements arranged end-to-end. Each ceramic element has parallel flat ends, a concave decorative front face and a rear face. The elements are of substantially uniform transverse cross section and are symmetrical about a central longitudinal axis. The rear face is bounded by a pair of flat, longitudinally extending marginal bonding surfaces which lie on mutually perpendicular planes. Each of the bonding surfaces joins a mutually perpendicular flat abutment face respectively which in turn join the front face. The length of each cornice element may equal tha of a wall tile.
[0026] The prior art teaches many forms of crown and other wall moldings but does not teach the combination of a molding and a wooden strip formed to nest with the molding and to form a foundation of mounting the molding and for supporting the molding; the prior art does not teach the method of mounting such. The present invention fulfills these needs and provides further related advantages as described in the following summary.
SUMMARY OF THE INVENTION
[0027] The present invention teaches certain benefits in construction and use which give rise to the objectives described below.
[0028] A plaster crown molding tile and a base support foundation beam provide mating nesting surfaces such that with the beam mounted to a wall surface, the tile may be placed securely onto the beam. A space is provided for a lighting fixture between the beam and the tile. Preferably, the nesting surfaces comprise a vertical and a horizontal surfaces. Preferably, a lighting fixture is installed between the tile and the foundation beam and is hidden from view as seen from below.
[0029] A primary objective of the present invention is to provide an apparatus and method of use of such apparatus that provides advantages not taught by the prior art.
[0030] Another objective is to provide such an invention capable of overcoming the problems with mounting plaster tiles to relatively non-planar walls.
[0031] A further objective is to provide such an invention capable of mounting plaster wall tiles more easily, quickly and with less breakage than traditional mounting methods are capable of.
[0032] A still further objective is to provide such an invention capable of supporting indirect lighting fixtures and of installing such fixtures more easily.
[0033] Other features and advantages of the present invention will become apparent from the following more detailed description, taken in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0034] The accompanying drawings illustrate the present invention. In such drawings:
[0035] [0035]FIG. 1 is an exploded perspective view of the preferred embodiment of the invention;
[0036] [0036]FIG. 2 is a perspective view of the finished assembly thereof; and
[0037] [0037]FIGS. 3 and 4 are side elevational full vertical sections thereof showing two embodiments.
DETAILED DESCRIPTION OF THE INVENTION
[0038] The above described drawing figures illustrate the invention in at least one of its preferred embodiments, which is further defined in detail in the following description.
[0039] The present invention is a wall molding apparatus for use in decorating a room. Such moldings have been broadly used in contemporary structures. The apparatus comprises the combination of a plaster crown molding tile 10 or 11 , and a base support foundation beam 20 which are joined by a fastener 30 such as nails or screws. The crown molding tile 10 provides an upright body portion providing a front decorative surface 14 and, in opposition thereto, a rear wall-engaging surface 16 and beam nesting surfaces 18 as is well shown in FIG. 2. The foundation beam 20 provides a wall mounting surface 26 and in opposition thereto, tile nesting surfaces 28 . The beam nesting surfaces 18 and the tile nesting surfaces 28 are each adapted by size, shape and position, for mutual contact with each other on angularly disparate surfaces, as best seen in FIGS. 3 and 4. Preferably, the nesting surfaces are vertical and horizontal on both the beam 20 and the tile 10 , but may have an alternative angular relationship. However, it is critical to have angularly disparate surfaces, such as orthogonal surfaces, as shown, in order to meet the requirement for secured mounting, and physical assurance against the plaster tile being broken. It is shown in FIG. 3 that a vertical nesting surface is best used in some tile configurations to take the fastener 30 , while in FIG. 4, a horizontal nesting surface is shown to be better suited for receiving the fastener 30 . Thus angularly disparate surfaces are inventively an improvement over the prior art. It should be noted the nesting surfaces in both tile and beam provide the same angle of separation thereby providing excellent nesting properties. The foundation beam is preferably made of wood which provides an improved mounting surface for both the tile and any ancillary items such as light fixtures and such. The wood beam, also, may be easily shaved to account for non-planar irregularities in the surfaces of wall surface 5 .
[0040] An adequate space 40 is formed between the foundation beam 20 and an outwardly angled topper portion 15 of the molding tile 10 for insertion and mounting of a lighting fixture 50 , which is preferably fastened to the foundation beam 20 as shown in FIG. 3.
[0041] The present invention also provides a method for mounting the wall molding tile 10 and comprises the steps of forming a vertical and a horizontal tile nesting surfaces 28 a and 28 b on the foundation beam 20 , mounting the foundation beam 20 in a horizontal attitude on the wall surface 5 with the tile nesting surfaces 28 a and 28 b positioned away from the wall surface 5 , and then forming a vertical and a horizontal beam nesting surfaces 18 a and 18 b on a plaster crown molding tile 10 ; placing the beam nesting surfaces 18 a , 18 b of the molding tile 10 into contact with the nesting surfaces 28 a , 28 b of the foundation beam 20 ; and engaging the molding tile 10 with the foundation beam 20 using the means for fastening 30 .
[0042] The method may further comprise, forming a space between the beam 20 and the outwardly angled topper portion 15 of the molding tile 10 for insertion and installation of the lighting fixture 50 .
[0043] While the invention has been described with reference to at least one preferred embodiment, it is to be clearly understood by those skilled in the art that the invention is not limited thereto. Rather, the scope of the invention is to be interpreted only in conjunction with the appended claims and it is made clear, here, that the inventor(s) believe that the claimed subject matter is the invention. | A plaster crown molding tile and a base support foundation beam provide mating nesting surfaces such that with the beam mounted to a wall surface, the tile may be placed securely onto the beam. A space is provided for a lighting fixture between the beam and the tile. Preferably, the nesting surfaces comprise orthogonal surfaces. | 4 |
[0001] This application claims priority from Provisional Application No. 60/277652 entitled “HARDWARE GRAPHICS SUPPORTED SYSTEM TO CREATE ULTRA THIN INTERNET CLIENTS” filed Mar. 27, 2001 by the inventor of the present application.
FIELD OF THE INVENTION
[0002] This invention relates generally to apparatus and methods for graphics display systems and more specifically to apparatus and methods for graphics display system for markup languages.
BACKGROUND OF THE INVENTION
[0003] Computer Graphics technology has made strong progress in relatively high-end machines such as desktops and laptops. Companies such as nVidia, ATI, Genesis, Silicon Video develop graphics chips to drive CRT, LCD displays and Video terminals. These graphics chips support hardware acceleration so that computationally intensive tasks are handled by the hardware freeing up the CPU to do other tasks. Also performing computations in hardware consumes less power than if done in software.
[0004] In well-known operating systems (OS) residing on the CPU, knowledge of the pixel data of the displayed information (i.e. the images created on the display) are generated by the OS. All known operating systems for display-based devices (e.g. Personal Computers, Laptops) are aware of the pixel data information. For instance, operating system such as Windows NT, UNIX and Linux generate the information to be displayed. Graphics chips provide support to the OS to off-load the CPU and provide graphics support for primitive objects. The display information generated by operating systems to be displayed is generic (i.e. any shape, form, format, font types, color can be displayed). Because the information displayed on a computer is generic, well-known graphics chip do not have the ability to generate the display data for these devices and hence this has to be done by the OS.
[0005] Low-end devices such as ultra thin clients in devices such as TVs, cellular phones, PDAs, pagers have not benefited from the innovations in the field of computer graphics. Low-end thin client devices do not have the processing power or the memory to generate graphics for high-resolution displays.
[0006] With the Internet playing a greater role in people's lives and demand for the Internet away from desktop computers increasing, the Internet is going to be ubiquitous. It will become available on all kinds of low-end devices including mobile devices. Displays such as high-resolution displays and micro-displays are expected to play an important role in the new mobile devices. Unfortunately, existing mobile devices (e.g. Cellular phones) do not have the memory or the CPU power to drive these high-resolution displays.
SUMMARY OF THE INVENTION
[0007] Thin clients, which display information fetched from the Internet, have limited display and display update requirements, and hence, a carefully chosen set of features required by Internet related applications (e.g. browser, email client, instant messaging system) can be implemented in a graphics chip. When pages for example are downloaded from the Internet they are displayed from top to bottom. Pages can be scrolled up, down, left or right needing simple graphics capability. In addition requirements to display text, images, simple geometric shapes like buttons, choice buttons, scroll bars can be incorporated into the graphics chip to off load the demands from a processing device, such as a micro-controller or low end CPU.
[0008] In embodiments of the present invention, the graphics chip operates in unison with a processing device which sends the necessary object information to the chip to display the information. The processing device fetches markup language data from the Internet or elsewhere, parses the markup language data and creates a table of objects. The graphics chip reads the properties of these objects, such as text, image, buttons, text field objects etc., and displays them on the display devices with the use of a number of graphics engines for processing text, image and geometry objects.
[0009] The present invention, according to a first broad aspect, is a method for converting markup language data into display data. This method includes translating the markup language data into object entries within an object table, each object entry comprising a set of properties related to an item for display on a display device; separating the object entries into a plurality of object types; and processing the object entries of each of the object types with separate graphic engines to generate display data corresponding to the object entries.
[0010] According to a second broad aspect, the present invention is a graphic display system, arranged to be coupled to a display device. The system includes an interface for receiving markup language data, a markup language processor, a memory device, an object table processor, and a plurality of graphic engines. According to this aspect, the markup language processor operates to translate the received markup language data into object entries, each object entry comprising a set of properties related to an item for display on the display device. The memory device operates to store an object table that stores the object entries. The object table processor operates to separate the object entries into a plurality of object types. Each graphic engine operates to process the object entries of a specific object type to generate display data corresponding to the object entries.
[0011] In a third broad aspect, the present invention is a processing apparatus, arranged to be coupled to a graphics engine apparatus including an object table. The processing device includes an interface for receiving markup language data; parsing logic for parsing the received markup language data into one or more markup language tags; and processing logic that operates, for a plurality of the parsed markup language tags, to insert an object entry corresponding to the particular parsed markup language tag into the object table. Each object entry comprises a set of properties related to an item for display on a display device.
[0012] The present invention, according to a fourth broad aspect, is a graphics engine apparatus, arranged to be coupled to a processing apparatus and a display device. The graphics engine apparatus includes a memory device, an object table processor and a plurality of graphics engines. The memory device operates to receive object entries from the processing apparatus and store the object entries within an object table, each object entry comprising a set of properties related to an item for display on the display device. The object table processor operates to separate the object entries into a plurality of object types. Each of the graphic engines operate to process the object entries of a specific object type to generate display data corresponding to the object entries.
[0013] Other aspects and features of the present invention will become apparent to those ordinarily skilled in the art upon review of the following description of specific embodiments of the invention in conjunction with the accompanying figures.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] Embodiments of the present invention are described with reference to the following figures, in which:
[0015] [0015]FIG. 1 is a simplified block diagram illustrating a typical computer system;
[0016] [0016]FIG. 2 is a simplified block diagram illustrating a thin client system according to an embodiment of the present invention;
[0017] [0017]FIG. 3 is a flow chart illustrating the steps for fetching of Markup language files by the micro-controller of FIG. 2;
[0018] [0018]FIG. 4 is a flow chart illustrating the steps for parsing of Object language and creating of a table representing the objects fetched in Markup files fetched in the process of FIG. 3;
[0019] [0019]FIG. 5 is a high-level block diagram of a thin client system according to an embodiment of the present invention;
[0020] [0020]FIG. 6 is a logical block diagram illustrating the functionality of the graphics chip of FIGS. 2 and 5;
[0021] [0021]FIG. 7 is a logical block diagram illustrating the functionality of the Raw Data Memory of FIG. 6;
[0022] [0022]FIG. 8 is a logical block diagram illustrating the functionality of the Processed Image Memory of FIG. 6;
[0023] [0023]FIG. 9 is a logical block diagram illustrating the functionality of the Graphics Engine 1 of FIG. 6 with the Raw Data Memory of FIG. 7;
[0024] [0024]FIG. 10 is a flow chart illustrating the steps for managing the scrolling of the display;
[0025] [0025]FIG. 11 is a flow chart illustrating the steps for managing movement of a mouse (cursor) on the display;
[0026] [0026]FIG. 12 is a flow chart illustrating the steps for managing clicks of a mouse on an object displayed on the display;
[0027] [0027]FIG. 13 is a flow chart illustrating the steps for managing user interaction with Internet based applications; and
[0028] [0028]FIG. 14 is an illustration of an example web page, which is displayed over two screens.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0029] In the following detailed description of embodiments of the present invention, reference is made to the accompanying figures, which form a part hereof, and in which is shown by way of illustration specific embodiments in which the invention may be practiced. It is to be understood that other embodiments may be utilized and structural changes may be made without departing from the scope of the present invention.
[0030] [0030]FIG. 1 shows a simplified block diagram of a typical high-end computer system 112 coupled between the Internet 106 and a display device 108 . The computer system 112 of FIG. 1 comprises a high-end CPU 100 , on which runs an OS 102 , and a graphics accelerator chip 104 . The OS 102 drives the graphics chip 104 for the applications that run on it and also for information fetched from the Internet 106 . The well-known graphics chip 104 provides low level graphics functionality for the display device 108 such as draw line, draw text, BIT BLT (Bit Block Transfer) etc.
[0031] [0031]FIG. 2 shows a simplified block diagram of a thin client system 206 according to an embodiment of the present invention coupled between the Internet 106 and a display device 108 . The system 206 comprises a micro-controller or a low-end CPU 200 and a high-level graphics chip 204 according to an embodiment of the present invention as will be described herein below. The graphics chip 204 according to various embodiments of the present invention provides high-level functionality such as one or more of drawing of text, images, geometry objects and high-level graphic objects such as buttons and scroll bars. Software 210 residing on the micro-controller or the low-end CPU 200 fetches Internet files from the Internet 106 , parses the files and sends high-level commands to the graphics chip 204 .
[0032] In FIG. 1, Internet access and display capability is provided by an application such as a browser which uses the capability of the OS 102 to create the information required to be displayed on the display device 108 . The OS 102 is responsible for displaying the text, images and other GUI related components such as button, scroll bar, etc. The graphics chip 104 only provides low level graphics accelerator capabilities. In the system of FIG. 2, according to an embodiment of the present invention, Internet access and display capability is provided by software 210 , which parses the markup language files and creates high level commands for the graphics chip 204 . The graphics chip 204 processes these commands and displays information on the display device 108 . The graphics chip 204 generates the display information for the text, GUI, images and the geometry shapes.
[0033] [0033]FIG. 3 depicts a flow chart illustrating the steps performed by the software 210 according to an embodiment of the present invention for fetching markup language files (e.g. HTML, SGML, XML, WML) and/or media (e.g. GIF, JPEG) files from the Internet 106 and creating entries in an Object Table within the graphics chip 204 described below with reference to FIGS. 6 - 9 . The process of FIG. 3 starts when a request is sent to the Internet 106 to fetch a markup language file at step 302 . The file when received is parsed at step 304 as will be described herein below with reference to FIG. 4. Next, the software 210 determines if there is a file referred to in the fetched markup file that needs to be fetched at step 306 . If there is not a file to be fetched at step 306 , the software completes the process.
[0034] If there is a file that needs to be fetched, a check is made to see if the to-be-fetched file is a media file at step 308 . If the to-be-fetched file is a media file, the media file is fetched and a corresponding entry is added in the Object Table at step 310 . The process is then returned to step 306 to check if there is another file to be fetched. If at step 308 it is determined that the file is not a media file, a check is made if the to-be-fetched file is a JAVA applet. If the to-be-fetched file is a JAVA applet, a corresponding entry is added in the Object Table at step 314 and the process is returned to step 306 to check for additional files that need to be fetched. If the to-be-fetched file is not a JAVA applet, the embedded file is ignored at step 316 and returned to step 306 to check if there is another file to be fetched.
[0035] [0035]FIG. 4 depicts a flow chart illustrating the steps performed by the software 210 according to an embodiment of the present invention for the parsing of the received markup file shown at step 304 of FIG. 3. The process starts by parsing the next markup language tag in the markup file at step 402 . A check is made to determine if there is a tag left at step 416 . If there is a tag left, a check is made to determine if the tag is a text-based tag at step 404 . If the tag is a text-based tag, a text entry is added in the Object Table and the process returns to step 402 to get the next tag. If the tag is not a text-based tag, a check is made to determine if the tag is for a Graphical User Interface (GUI) based object at step 408 . If it for a GUI-based object, then an entry representing the GUI is added into the Object Table at step 410 and the process returns to 402 to get the next tag. If the tag is not a GUI-based tag, a check is made to determine if the tag is a geometry-based tag 412 . If the tag is a geometry-based tag, a corresponding entry is made in the Object Table at step 414 and the process returns to step 402 to check if there is any tag left. If the tag is not a geometry-based tag (and therefore not a text-based, GUI-based or geometry-based tag), the tag is ignored at step 418 and the process is returned to 402 to get the next tag. The process ends when there is no markup language tag left to process.
[0036] [0036]FIG. 5 depicts a high-level block diagram of an embedded system 510 providing Internet access capability for ultra-thin client systems according to an embodiment of the present invention. Within this system 510 , the micro-controller 200 is coupled to an external media 500 such as an Ethernet connection through an RJ/45 port. The graphics chip 204 receives data and commands from the micro-controller 200 via a databus 506 through a memory mapped address space mapped in the micro-controller 200 . The graphics chip 204 connects to the external display device 108 through a connector such as a VGA or a Video connector 504 . External memory 508 is an optional part of the embedded Internet access system 510 . External memory 508 is used to store the media files, which may not fit in the on-chip RAM in the graphics chip 204 .
[0037] [0037]FIG. 6 depicts a logical block diagram of the graphics chip 204 of FIGS. 2 and 5. As depicted, the graphics chip 204 comprises a Raw Data Memory (RDM) 600 , Processed Image Memory (PIM) 602 , Frame Buffer Memory (FBM) 604 and Graphics Engines 1-3 606,608.610. The RDM 600 is accessible to both the micro-controller 200 and the graphics chip 204 and is used to store the Object Table described herein below with reference to FIG. 7. The PIM 602 contains pixel data display information created from processing the raw data in the RDM 600 . Raw data in RDM is processed into final display data ready to be copied into the FBM 604 . This multi-buffer scheme is used since there is very little time between two consecutive updates of the frame buffer, called a vertical retrace. The FBM 604 is updated only between two consecutive frame updates to avoid Image tearing.
[0038] Graphics Engine 1 (GE1) 606 reads the entries in the Object Table in the RDM 600 via event 614 , generates the image display data and outputs this image display data to the processed image buffer of PIM 602 via event 616 . PIM 602 may be smaller than the FBM 604 . In such a case, GE1 606 would create only a portion of the final image in each run. Thus, it would take R/r such generations to create a complete display screen where R is the number of rows in FBM 604 and r is the number of rows in PIM 602 .
[0039] Graphics Engine 2 (GE2) 608 copies the image from the PIM 602 via event 618 and copies the image into the FBM 604 via event 620 . GE2 608 performs the copying when Graphics Engine 3 (GE3) 610 is between two refresh cycles, which is indicated to GE2 by event 612 .
[0040] GE3 610 reads the FBM 604 via event 624 and processes the data to be sent to the display 108 . This FBM 604 contains data in the pixel display form (i.e. the data to be displayed on the connected display 108 ). The size of this memory is C×R×B bytes, where C is number of columns in pixels of the display, R is the number of rows in pixels of the display and B is the bytes of data per pixel.
[0041] [0041]FIG. 7 depicts a logical block diagram illustrating the RDM 600 in relation to the micro-controller 200 and GE1 606 . The RDM 600 comprises the Command and Control Register (CCR) 702 , which enables the micro-controller 200 to send commands to the chip 204 , and the Object Table 700 , which contains information about the different objects and object data to be displayed on the page fetched from the Internet 106 .
[0042] Further, the RDM 600 comprises additional space 708 not used by the Object Table 700 and CCR 702 . This additional space 708 is used to store information about the different objects in the Object Table 700 . For example, this is the memory space in which text and image data is placed by the micro-controller 200 .
[0043] In embodiments of the present invention, the CCR 702 supports the following commands:
[0044] 1. Refresh—Refresh a complete page or a small area of the FBM 604 .
[0045] 2. Move Mouse—Move a mouse to an absolute location or relative to the previous location. X and Y position is provided with this command.
[0046] An event 704 is sent to the GE1 606 , each time a micro-controller writes a command into CCR 702 .
[0047] The micro-controller 200 fills the Object Table 700 according to the results of the parsed information received in the web pages. The following information is provided for each object in the Object Table 700 :
[0048] Location and Size: Each object's upper left hand corner and its width and height is stored in the RDM 600 . Objects are arranged in increasing pixel order in the Y direction. This makes it efficient to find the objects within a given area on the display screen. The objects for the complete web page are placed in the RDM 600 , and not just the ones, which are currently displayed.
[0049] Object Type: Type of the object to be displayed. The following is an example list of object types:
[0050] 1. Text
[0051] 2. Image (GIF, JPEG etc.)
[0052] 3. Choice Button (circle with associated text)—Selected and not selected states.
[0053] 4. Radio Button (square with associated text)—Selected and not selected states.
[0054] 5. Scroll bar (Horizontal, Vertical)—This object is displayed by the ASIC without the intervention of the micro-controller 200 .
[0055] 6.Button with associated text (depressed and non depressed states)
[0056] 7. Text Area (with associated scroll bar and rectangular box).
[0057] 8. Line (Vertical and Horizontal line)
[0058] 9. Table
[0059] Object Properties: Properties related to each object are stored. Different objects have different properties. For example, text has number of characters, font type and font size as its properties. A button object has number of characters (for the text), state of button (passive, depressed) etc. as the properties.
[0060] Data pointer: The data pointer points to the data related to the object i.e. text for the Text object, image data for an Image object. Object data can reside on the on-chip memory or on the optional external memory.
[0061] A further important property is “fixed”. This is used to identify objects, which are fixed on the displayed screen and are not moved or scrolled. These objects allow different configurations of the browser. Some objects, which are “fixed”, are scroll bars, menu buttons, status bar and the title bar.
[0062] Table 1 shows an example of what will be stored in the RDM Object Table 700 for the 2 screens of a sample web page as shown in FIG. 14.
TABLE 1 Example Object Table 700 in RDM 600 Y X Object Pixel, Pixel, Object Data Valid Y Size X Size Type Object Properties pointer Yes 10, 10, GIF Size, Image type Pointer 250 620 Image to image Yes 270, 10, Text Number of characters, Pointer 50 620 Font Type, Font Size, Bold/Italic/Underline Yes 330, 301, GIF Size, Image type Pointer 50 300 Image to image Yes 330, 301, GIF Size, Image type Pointer 50 610 Image to image Yes 380, 30, GIF Size, Image type Pointer 50 300 Image to image Yes 380, 301, GIF Size, Image type Pointer 50 610 Image to image Yes 510, 10, Text Number of characters, Pointer 280 300 font, size to text Yes 510, 301, GIF Size, Image type Pointer 290 600 Image to Yes 810, 10, Text Number of characters, Pointer 30 610 font, size to text Yes 850, 60, Choice Number of characters, Pointer 10 400 Button Selected to text Yes 865, 60, Choice Number of characters Pointer 10 400 Button to text Yes 880, 30, Text 20 500 Field Yes 880, 550, Button Number of characters Pointer 20 60 to text
[0063] [0063]FIG. 8 is a logical block diagram illustrating PIM 602 , according to an embodiment of the present invention, in relation to GE1 and GE2 608 . The PIM 602 comprises pixel data display information created from processing the raw data in RDM 600 . Raw data in RDM 600 is processed into final information ready to be copied into FBM 604 . PIM 602 comprises four logical sections, Processed Image Buffer (PIB) 800 , Scroll Buffer (SB) Up 802 , SB Down 804 and Mouse Buffer (MS) 812 .
[0064] The PIB 800 comprises the processed pixel image which has to be displayed on the display. This memory may have the same size as that of the FBM 604 ; however since the size of the FBM is potentially large (640×480×2×8 bits for 16 bit color VGA and 800×600×2×8bits for 16 bit color SVGA) keeping a complete copy of the buffer will need larger memory. PIB 800 contains the image, which the GE2 608 copies to the FBM 604 .
[0065] SB Up, SB Down 802 , 804 contain the pixel data of the image, which is to be displayed when the web page is scrolled in the up and down directions respectively.
[0066] MB 812 is used to store pixel data covered by the cursor on the screen. As the mouse moves around on the screen, the cursor covers and uncovers parts of an image. The MB 812 keeps the covered part of the display so that it can be copied back when the mouse moves to a new location.
[0067] Each buffer in the PIM 602 is associated with “status” information 806 , 808 , 810 that indicates that the information in the corresponding memory is ready for the display.
[0068] [0068]FIG. 9 is a logical block diagram illustrating the GE1 606 and its relation with RDM 600 and PIM 602 . As depicted, GE1 606 comprises Object Table Processor 900 , Text Engine 902 , Image Engine 904 and Geometry Engine 906 . The Object Table Processor 900 reads each entry in the Object table 700 and forwards the object to be processed to the corresponding engine depending on the kind of object. Text related objects are passed to the Text Engine 902 , which takes the text and generates pixel data for the text in proper font type and font size. Image objects are passed to the Image Engine 904 , which reads the image for example in JPEG or GIF, format and generates the necessary pixels for the image. Geometry objects such as line, box, button etc are passed to the Geometry Engine 906 , which draws the objects, such as lines, boxes and buttons. Outputs from each of the engines are stored within the PIB 800 of the PIM 602 .
[0069] [0069]FIG. 10 is a flow chart illustrating the steps performed for managing the scrolling of the display 108 . The process is outlined for scrolling down of the display, though it should be noted that a similar process is used to scroll left, right and up for the display 108 . The process starts when a scroll event is received by GE2 608 at step 1002 . The scroll event is generated by a mouse or an equivalent device outside the micro-controller 200 and graphics chip 204 . GE2 608 then does a block move of display data in PIB 800 at step 1004 . The size of the move depends on the size of the SBs 802 , 804 . The size of the move is the difference in size of the PIB 800 and SBs 802 , 804 . A check is made to determine if SB Down's 804 status 810 is ready at step 1006 . If the status is not ready, GE2 608 waits at step 1008 until the status is ready. If the SB Down is ready, GE2 608 copies the image data from the SB Down 804 into the bottom portion of PIB 800 at step 1010 . GE2 608 then sets the status of the SB Down 804 to “not ready” at step 1012 and instructs GE1 606 to update the SB Down 804 at step 1014 to end the process of scrolling. The next frame refresh by GE3 610 would read the updated data in the PIB.
[0070] [0070]FIG. 11 is a flow chart illustrating the steps performed according to an embodiment of the present invention for managing the movement of the mouse on the display 108 . The process starts when a mouse move event is received by the micro-controller 200 at step 1102 . The micro-controller 200 provides the new location to the graphics chip through a mouse move command at step 1104 . Subsequently, the GE2 608 copies the contents of MB 812 into the current location of the mouse pointer in the FBM 604 at step 1106 and copies the image data from the new location of the mouse from the FBM 604 into the MB 812 with its associated coordinates at step 1108 . It then draws the mouse cursor in FBM 604 in the new location of the mouse pointer at step 1110 .
[0071] [0071]FIG. 12 is a flow chart illustrating the steps performed for managing mouse click events by the software 210 on micro-controller 200 . The process starts when micro-controller 200 receives a mouse click event. The micro-controller 200 at all times remembers the current position of the mouse and a list of the objects which are affected by the click of a mouse. Subsequently, the micro-controller 200 retrieves the next object from the list of objects which are affected by a mouse click at step 1204 and checks to see if there is any object left within the list at step 1206 . If there is another object left, the micro-controller 200 checks if the mouse click is on the object at step 1208 . The following is used to find out if the mouse click occurred on the object.
[0072] X, Y coordinates of where the mouse is clicked,
[0073] Top of the current displayed page
[0074] Location of all the objects in the web page.
[0075] If the mouse is on this object, the micro-controller 200 triggers the performing of the action depending on the object type at step 1210 . If the mouse is not on this object, the process returns to step 1204 to get another object from the list of objects. The process ends when there are no more objects or if it is determined that the mouse is on a particular object.
[0076] [0076]FIG. 13 is a flow chart illustrating the steps for managing user actions, such as entering text into a text field or selection/deselection of an icon choice button. The process starts when the micro-controller 200 receives an event at step 1302 . When the text is entered into a text field or a choice button is selected, the micro-controller 200 modifies the Object Table 700 in the RDM 600 at step 1304 . The micro-controller 200 issues a “Refresh” command at step 1306 which instructs GE1 606 to re-process the image for a given rectangular region. GE1 606 then instructs GE2 608 to copy the processed image into the appropriate section in the FBM 604 at step 1308 and the process is terminated.
[0077] Although the above described embodiments were specific to graphic support systems coupled to the Internet, it should be noted that in alternative embodiments, the Internet could be any network or local environment which has access to markup language files with one or more of text, image and geometry objects. For instance, the markup language files could be accessed from a non-network source such as a local memory device.
[0078] Although the above description depicts a graphics support system in which micro-controller 200 and graphics chip 204 are separate entities locally coupled together, this should not limit the scope of the present invention. In one alternative embodiment of the present invention, the functionality of the two devices 200 , 204 are integrated together on a single semiconductor device. In another alternative embodiment, the graphics engine capability of the graphics chip 204 resides on the micro-controller 200 through an implementation within software. In this embodiment, an external graphics chip such as device 104 of FIG. 1 may be required. In yet a further alternative embodiment, the micro-controller 200 or the software 210 and the graphics chip 204 or equivalent devices may be integrated within different systems separated by a network.
[0079] Although the above descriptions of the present invention specify the use of a micro-controller, it should be recognized that other processing devices could be utilized such as a CPU or a Digital Signal Processor (DSP).
[0080] The foregoing description of a preferred embodiment of the invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise forms disclosed. Obviously, many modifications and variations will be apparent to practitioners skilled in this art. It is intended that the scope of the invention be defined by the following claims and their equivalents. | Applications such as web-browsers, email clients are currently available on high-end devices such as personal computers, workstations and laptops. The Internet has started to also become available on thin client devices such as touch panel displays, TVs, mobile phones and other handheld devices. The technology currently available for these thin client devices cannot easily utilize the technology from the high-end devices with respect to graphics due to limits on the memory and CPU power available. To overcome this problem, it is necessary to recognize that thin client devices have limited display and display update requirements, and hence, a carefully chosen set of features required by Internet related applications (e.g. browser, email client, instant messaging system) can be implemented in a graphics chip. In particular, a graphics chip can operate in unison with a processing device which sends necessary object information to the graphics chip to display. The processing device fetches the markup language data, parses the markup language data and creates a table of objects. The graphics chip reads the properties of these objects, such as text, image, buttons, text field objects etc., and displays them on the display devices with the use of a number of graphics engines for processing text, image and geometry objects. | 6 |
BACKGROUND OF THE INVENTION
1. Field of Invention
The present invention relates to preparations for topical application which contain tolnaphtate (hereinafter abbreviated as TOL) known as an antifungal agent. More specifically the Preparations of this invention are so designed as to form a flexible, strong, transparent film on the skin and gradually release TOL therefrom.
2. Prior Art
So far, tinctures, creams, gels, or the like preparations have been used for the topical treatment of mycosis.
TOL bas a potent action against fungi, especially against Trychophytons and therefore, it has long been used for the treatment of tinea pedis. However. in many cases, mycosis as represented by athlete's foot primarily occurs at moist Parts of the body. So, when an ointment or a gel preparation is applied to the affected part, it makes the affected part even more moist, thereby giving a strange feeling or staining clothing. These are shortcomings in using ointments or gel preparations. A tincture has such shortcomings as to take longer time to dry on the parts of the body to which it is applied. Furthermore it has been another shortcoming that conventional TOL-preparations result in TOL becoming crystallized in storage or when applied because of its property of being hardly soluble in most solvents.
SUMMARY OF THE INVENTION
The present invention provides film-formation-type anti-fungal preparations for topical application, consisting essentially of about 0.1% to about 1.5% of tolnaphtate, about 10% to about 20% of a dimethylaminoethyl methacrylate-methacrylic acid ester copolymer (hereinafter abbreviated as DMMA-MA), and 0.5% to about 10% of a medium chain fatty acid ester in an alcoholic solvent but containing practically no water.
BRIEF DESCRIPTION OF THE DRAWING
The ordinate shows TOL amount in the skin, while the abscissa shows time. The remaining amounts of TOL in the skin are shown by the mark " ○" for the control and by the mark " ○" for the Example 1 preparation disclosed below.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Problems to be Solved
In view of the Problem above the present inventors tried to find such base ingredients as to prevent TOL from crystallization in storage or even after application, and as to enhance transdermal absorbability of TOL and, consequently, they have completed the present invention. The preparations of this invention enhance and sustain the action of TOL and, therefore, they are expected to give an excellent efficacy in a once-a-day application.
The preparations of this invention are capable of forming a flexible strong film on the skin when applied and of keeping the drug effect for a long period of time. Proportions used in this invention are shown as percentage by weight (w/w %) of certain additive to the total weight of the whole preparation.
Means to Solve the Problem
This invention can be achieved by dissolving about 0.1%-- about 1.5% of TOL, about 10%--about 20% of DMMA-MA, and 0.5% --about 10% of a medium chain fatty acid ester in an alcoholic solvent. If necessary, about 0.1% --about 2.5% of a thickening agent and/or a plasticizer may be further added.
lOL used in this invention is a potent antifugal agent and very popular as cream- or gel-preparations. Eudragit® E100 may be a good representative for DMMA-MA.
The medium chain fatty acid ester includes glyceryl monocaprate (GMC). tetraglyceryl monocaprate (TGMC), propyleneglycol dicaprate (PGDC), tetraglyceryl hexacaprate (TGHC), and the like. TGMC is especially preferred.
The aqueous alcohol used in this invention means such a dry lower alkanol as to contain substantially no water. Lower alkanol includes ethanol, propanol, isopropanol, and the like.
Thickening agents including cellulose derivatives such as ethyl cellulose (EC), hydroxypropyl cellulose (HPC), hydroxypropylmethyl cellulose (HPMC), and the like are preferably used. Plasticizers including propylene glycol (PG), polyethylene glycol (PEG), and the like are preferably used.
The tinea pedis preparations of this invention are remarkably improved in enhancing the transdermal absorbability of TOL and in making drug effectiveness last for a long time as compared with conventional preparations, creams, gels, tinctures or the like. So, it can be expected that once-a-day application of the preparation is enough to attain good efficacy. The present invention is explained in more detail in the following Examples and Experiments, which are not intended to limit the scope of the invention.
EXAMPLE 1
Isopropanol (76g) and 5g of TGMC were put in a closed type vessel equipped with a stirrer. DMMA-MA (15g; EUDRAGIT® E100) and 3g of EC were gradually added thereto to give a clear solution, to which 1g of TOL was dissolved with stirring to make the objective preparation (100 g) of this invention.
EXAMPLES 2 -4
In substantially the same manner as in Example 1, the following instant preparations for tinea pedis were obtained.
TABLE 1______________________________________ Example 2 3 4 ControlComponents (%) (%) (%) (%)______________________________________TOL 1 1 1 1DMMA-MA 15 15 15 15GMC 5TGMC 5TGHC 5PG 3Ethanol 79 79 81Isopropanol 79______________________________________
EXPERIMENT 1
The precipitation of crystals was examined to study shelf life stability on each of the following preparations. The e in solution and the presence of crystals were examined by observation with the eye or under a microscope.
Preparations Examined
Preparations manufactured in Examples 1 to 4
Control: Control preparation shown in Table 1
TABLE 2______________________________________Stored at 5° C. in tightly closed container After After After After AfterPrepa- 1 2 1 2 3ration Initial Week Weeks Month Months Months______________________________________1 -- -- -- -- -- --2 -- -- -- -- -- ○3 -- -- -- -- -- --4 -- -- -- -- -- --Control -- -- ○______________________________________ (Remarks) --: No change in solution & no formation of crystals were observed. ○ : Change in solution & formation of crystals were observed.
EXPERIMENT 2
The in vivo transdermal absorption study shown in the following experiments was carried out, basically according to the undermentioned method:
Test Method
1. Male Wister rats (9 weeks of age, n=5-8) anesthetised by urethane have their abdominal hair removed carefully with electric clippers and electric razor.
2. The rat is fixed on its back, and then an absorption chamber (application area: 10 cm 2 ) is fixed on the surface of the hairless abdomen with an instant adhesive.
3. A pre-fixed dose of a test material (2 mg as TOL per rat) is placed into the chamber.
4. After a certain period of time, the coating film formed on the skin in the chamber is removed off with distilled water and collected into a suitable vessel.
5. The chamber is removed and the application area of the skin is cut off.
6. The sample in item 4 and the piece of the skin in Item 5 are employed for the TOL content measurement by HPLC.
Along the test method mentioned above, a comparative study for transdermal absorption of TOL was carried out on some instant preparations and a commercially available one. TOL amount in the skin 4 hours after application is as follows.
Result
TABLE 3______________________________________ TOL Amount in the skinPreparation (mcg/10 cm.sup.2)______________________________________Example 1 9.04 ± 2.50Example 2 3.97 ± 1.08Example 3 8.84 ± 2.85Example 4 6.21Commercially 0.54 ± 0.06Available______________________________________
Remarks
Commercially Available: Pasca® Gel (by Shionogi & Co., Ltd., containing 1% of TOL)
The instant preparations of this invention exhibit much her transdermal absorbabilities than the gel preparation commercially available one) which has generally been believed to exhibit: a high absorbability.
EXPERIMENT 3
TOL amounts in the skin were measured at several points of time for the preparation of Example 1 and a commercially available Preparation (1% Pasca® Gel: made-by Shionogi & Co., Ltd.), to evaluate substantiality of TOL.
Result
The result is shown in the drawing. As compared with the control the preparations of this invention were remarkably improved in the transdermal absorbability of TOL and, additionally, they are capable of keeping high TOL concentrations in the skin for a long period of time. Consequently, the preparation of this invention exhibits a much larger area under the curve (AUC), the fact of which demonstrates a high bioavailability of TOL.
From those results, it is expected that the tinea pedis preparations of this invention will give an excellent efficacy in the treatment at only a once-a-day application. | Film-formation-type antifungal preparations for external application, consisting essentially of about 0.1% to about 1.5% of tolnaphtate, about 10% to about 20% of a dimethylaminoethyl methacrylate-methacrylic acid ester copolymer and 0.5% to about 10% of a medium chain fatty acid ester in an alcoholic solvent but containing practically no water. | 0 |
BACKGROUND OF THE INVENTION
This invention is directed to novel compounds having anti-diabetic activity. Each compound of this invention is available by conversion of human proinsulin or an intermediate derived from human proinsulin.
Human proinsulin is recognized to exhibit anti-diabetic activity, albeit at a much lower level, relative to human insulin itself. The compounds of this invention exhibit anti-diabetic activity at a level much greater than that demonstrated by human proinsulin.
SUMMARY OF THE INVENTION
Thus, this invention is directed to a class of compounds having the formula ##STR2## and pharmaceutically acceptable non-toxic salts thereof in which X is --OH, -Ala-Leu-Glu-Gly-Ser-Leu-Gln-OH, or -Ala-Leu-Glu-Gly-Ser-Leu-Gln-Lys-Arg-OH.
DETAILED DESCRIPTION OF THE INVENTION
This invention is directed to three peptides, any of which may be in the form of its pharmaceutically acceptable non-toxic salt.
The peptide sequences and corresponding short-hand descriptions used herein in which the term HPI denotes human proinsulin are as follows: ##STR3##
Included in the compounds of this invention are their pharmaceutically acceptable non-toxic acid addition salts and their pharmaceutically acceptable non-toxic carboxylic acid salts.
The term "pharmaceutically acceptable non-toxic acid addition salts" encompasses both organic and inorganic acid addition salts including, for example, those prepared from acids such as hydrochloric, sulfuric, sulfonic, tartaric, fumaric, hydrobromic, glycolic, citric, maleic, phosphoric, succinic, acetic, nitric, benozic, ascorbic, p-toluenesulfonic, benzenesulfonic, naphthalenesulfonic, propionic, carbonic, and the like, or salts, such as, for example, ammonium bicarbonate. Preferably, the acid addition salts are those prepared from hydrochloric acid, acetic acid, or carbonic acid. Any of the above salts can be prepared by conventional methods.
The term "carboxylic acid salts" includes, for example, zinc, ammonium, alkali metal salts such as sodium, potassium, and lithium, and the like. Preferred carboxylic acid salts are the zinc and sodium salts.
For the sake of convenience, the amino acids of the peptides referred to herein may be described by their approved single-letter or three-letter shorthand designations.
These designations are as follows:
______________________________________Single-Letter Three-Letter Amino Acid______________________________________A Ala AlanineR Arg ArginineN Asn AsparagineD Asp Aspartic AcidC Cys CysteineE Glu Glutamic AcidQ Gln GlutamineG Gly GlycineH His HistidineI Ile IsoleucineL Leu LeucineK Lys LysineF Phe PhenylalanineP Pro ProlineS Ser SerineT Thr ThreonineY Tyr TyrosineV Val Valine______________________________________
The compounds of this invention can be prepared by routine peptide synthesis methods.
Alternatively, and preferably, the compounds of this invention can be prepared from human proinsulin. Human proinsulin is available via a variety of routes, including organic synthesis, isolation from human pancreas by conventional methodology, and, more recently, recombinant DNA methodology.
In broad outline, the production of proinsulin using recombinant DNA methodology involves obtaining, whether by isolation, construction, or a combination of both, a sequence of DNA coding for the amino acid sequence of human proinsulin. The DNA coding for human proinsulin then is inserted in reading phase into a suitable cloning and expression vehicle. The vehicle is used to transform a suitable microorganism after which the transformed microorganism is subjected to fermentation conditions leading to (a) the production of additional copies of the human proinsulin gene-containing vector and (b) the expression of human proinsulin or a human proinsulin precursor product.
In the event the expression product is a human proinsulin precursor, it generally will comprise the human proinsulin amino acid sequence joined at its amino terminal to another protein, whether foreign or that normally expressed by the gene sequence into which the human proinsulin gene has been inserted. The human proinsulin amino acid sequence is joined to the protein fragment through a specifically cleavable site, typically methionine. This product is customarily referred to as a fused gene product.
The human proinsulin amino acid sequence is cleaved from the fused gene product using cyanogen bromide after which the cysteine sulfhydryl moieties of the human proinsulin amino acid sequence are stabilized by conversion to their corresponding S-sulfonates.
The resulting human proinsulin S-sulfonate is purified, and the purified human proinsulin S-sulfonate then is converted to human proinsulin by formation of the three properly located disulfide bonds, using, for example, the method of U.S. Pat. No. 4,430,266. The resulting human proinsulin product then is purified using recognized methodology.
The compounds of this invention can be prepared by enzymatic digestion of human proinsulin. Thus, treatment of human proinsulin with trypsin leads to the production of, among others, (65-Al split)HPI. Treatment of the product mixture by gel filtration followed by reverse phase high performance liquid chromatography (HPLC) permits recovery of purified (65-Al split)HPI.
The (65-Al split)HPI is used to prepare the other compounds of this invention. Thus, treatment of (65-Al split)HPI with carboxypeptidase B yields des(64,65)HPI. Similarly, treatment of (65-Al split)HPI with chymotrypsin yields des(57-65)HPI.
As noted, the compounds of this invention have an insulin-like, anti-diabetic effect substantially greater than that recognized for human proinsulin.
The compounds of this invention, due to their insulin-like activity, are useful in the treatment of diabetes. As such, they can be used in a variety of pharmaceutical compositions and formulations and can be administered by a variety of conventional routes, such as intramuscular, intravenous, subcutaneous, and intraperitoneal.
In administering the compounds of this invention, the pharmaceutical forms suitable for injection include sterile aqueous solutions or dispersions and sterile powders for reconstitution into sterile injectable solutions or dispersions.
Sterile injectable solutions can be prepared by incorporating the compounds of this invention in the calculated amount of the appropriate solvent along with various of the other ingredients, as desired.
The following examples are provided to illustrate this invention. They are not intended to be limiting on the scope thereof.
EXAMPLE 1
Preparation of (65-Al split)HPI
Human proinsulin (312 mg wet wt.) was dissolved in 57 ml of 0.1M Tris buffer (final pH 7.0), and the solution was warmed to 25° C. in a water bath. Trypsin (25.1 micrograms) dissolved in 57 microliters of 0.05M Tris-0.02M CaCl 2 (pH 7.0) was added. The reaction was terminated after 68 minutes by lowering the pH of the solution to 2.5 by addition of acetic acid.
The acidified solution (57 ml) was chromatographed on a 5×200 cm G50 Superfine Sephadex column at 6° C. using 1M molar acetic acid as the column solvent. A large broad peak containing unreacted HPI, (32-33 split)HPI, and (65-Al split)HPI eluted first and was fairly well separated from a second peak containing di-Arg 31 ,32 human insulin.
Column fractions were pooled as follows:
______________________________________ Protein content Beginning and end of pool asPool points of pool determined by u.v.*______________________________________A 1768-2146 ml 83.3 mg of a mixture of HPI and monosplit HPI'sB 2146 ml-2464 ml 98.1 mg of a mixture of HPI and monosplit HPI'sC 2464 ml-2843 ml 34 mg of di-Arg.sup.31,32 human insulin______________________________________ *Amounts calculated based on O.D..sup.276 and a calculated extinction coefficient.
The above pools were lyophilized.
The components in the three lyophilized pools were further resolved by chromatographing the materials in three portions on a 2.5×60 cm C-18 HPLC column using 34% CH 3 CN in 0.5% trifluoroacetic acid as the column solvent.
A portion (79 mg) of Pool A dissolved in dilute HCl (final pH=2) was applied to the column and yielded two pools of interest (D and E).
______________________________________ Protein content Beginning and end of pool asPool points of pool determined by u.v.______________________________________D 519-627 ml 34.4 mg of pure (32- 33 split)HPI [43% of 79 mg]E 700-808 ml 14.7 mg of 70% pure (65-Al split)HPI [18.5% of 79 mg]______________________________________
A mixture of 4 mg of Pool A and 98 mg of Pool B was dissolved in 0.01N HCl, pH=2, applied to the column, and chromatographed to yield Pool F. Then Pool C (34 mg) was dissolved in 0.01N HCl, applied to the column, and chromatographed to yield Pool G.
______________________________________ Protein content Beginning and end of pool asPool points of pool determined by u.v.______________________________________F 10.7 mg of pure (32- 33 split)HPI (10.5% of 102 mg applied to column)G 20.3 mg of 84% pure di-Arg.sup.31-32 human insulin (59.7% of 34 mg applied of column)______________________________________
The purity of the samples was determined using analytical HPLC, polyacrylamide basic disc gel electrophoresis, and analytical Fast Protein Liquid Chromatography (FPLC). Amino acid analysis and amino acid sequencing were used to establish the identity of the compounds.
(65-Al split)HPI (11.73 mg wet weight, from Pool E) was chromatographed in five runs (approximately 2 mg load per run) on a high performance 1×25 cm Beckman Ultrasphere Octyl column.
Isocratic elution with a solvent of approximately 27.5% CH 3 CN in 0.07M NH 4 OAc, pH 7.1, was used to resolve components, and 4.34 mg of purified (65-Al split)HPI were obtained. This solution was then lyophilized. The resulting solids were dissolved in 0.05 M NH 4 HCO 3 , pH 9.0, and chromatographed on a 0.9×30 cm G25M Sephadex column (equilibrated in 0.05M NH 4 HCO 3 , pH 9.0) to obtain 3.62 mg of pure (65-Al split)HPI as determined by u.v. (83% of 4.34 mg).
EXAMPLE 2
Preparation of des(64,65)HPI
A. Initial Small Preparation
Crude (approximately 70% pure by HPLC) (65-Al split)HPI (2.10 mg wet wt.) dissolved in 0.5 ml of 0.1M Tris buffer (pH 7.5) was treated with 4.04 micrograms of Carboxypeptidase B for 40 minutes at 25° C. The reaction was terminated by adding 1.0 ml of 7M urea--0.2M acetic acid. The solution was chromatographed on a 0.9×40 cm G25M Sephadex column equilibrated with 2% acetic acid and then lyophilized.
Solid material (1.91 mg) was purified on a 5×50 mm Pharmacia Mono S column equilibrated with 7M urea--0.1M acetic acid. A linear salt gradient from 0.07 to 0.3M NaCl over 30 minutes was used to elute the protein. The main peak material was recovered and stored at 4° C.
B. Larger Preparation
Crude (approximately 70% pure by HPLC) (65-Al split)HPI (10.46 mg wet wt.) in 2.5 ml of 0.1M Tris (final pH 7.1) was treated with 20.1 micrograms of Carboxypeptidase B for 40 minutes at 25° C. The reaction was terminated by acidifying to pH 3.4 with 7M urea--0.1M acetic acid and 1M HCl. The main peak solution from Part A described above was pooled with this reaction product for the following G50SF step.
The resulting des(64-65)HPI was applied to a 2.5×125 cm G50SF Sephadex column and eluted at 6° C. with 1M acetic acid. Fractions containing des(64-65)HPI were pooled and lyophilized to obtain 8.07 mg of the desired product as determined by u.v. analysis.
The solids from the G50SF Sephadex column were chromatographed on a 5×50 mm Pharmacia Mono S cation exchange column equilibrated with 7M urea--0.1M acetic acid. A linear gradient of 0.07 to 0.3M NaCl over 30 minutes was used to elute the protein. The main peak material was chromatographed on a 0.9×40 cm G25M Sephadex column equilibrated with 2% acetic acid to obtain 3.36 mg of pure des(64-65)HPI as determined by u.v. analysis.
EXAMPLE 3
Preparation of des(57-65)HPI
A. Initial Small Preparation
Crude (approximately 50% pure by HPLC) (65-Al split)HPI (2.86 mg wet wt.) dissolved in 1.29 ml of 0.1M CaCl 2 -0.08M Tris (final pH 7.8) was treated at 25° C. with 2.56 micrograms of chymotrypsin. Aliquots containing 0.436 mg of digested protein was acidified with 7M urea-0.05M HCl at 10, 20, 30, 45, and 60 minutes to terminate the reaction. The aliquots were assayed by HPLC to determine the optimum digestion time. Based upon these results, the optimum digestion time was estimated to be about 38 minutes.
B. Larger Preparation
Crude (approximately 50% pure by HPLC) (65-Al split)HPI (16.16 mg wet wt) was digested as above for 38 minutes at 25° C. and then acidified to pH 3.0 with 5M HCl. The 30, 45, and 60 minute samples from Part A were added to the mixture for the following G50SF chromatography step.
The solution of the resulting crude des(57-65)HPI was chromatographed at 6° C. on a 2.5×125 cm G50SF Sephadex column equilibrated with 1M acetic acid. Fractions containing the des(57-65)HPI were pooled and lyophilized to obtain 5.83 mg of the desired product as determined by u.v. analysis.
The solid product from the G50SF Sephadex column was chromatographed on a 5×50 mm Pharmacia Mono S cation exchange column equilibrated with 7M urea-0.1M acetic acid. A linear gradient from 0 to 0.4M NaCl over 30 minutes was used to elute the protein. The main peak material was chromatographed on a 0.9×40 cm G25M Sephadex column packed in 2% acetic acid to obtain 3.0 mg of pure des(57-65)HPI as determined by u.v. analysis.
BIOLOGICAL ACTIVITY
A. IM-9 Radioreceptor Assay
IM-9 cells were grown in RPMI media containing 2mM glutamine, 25 mM HEPES, and 10% fetal bovine serum. Cells were harvested by centrifugation, washed, and resuspended in HEPES assay buffer, pH 7.6 [DeMeyts, P., Insulin and Growth Hormone Receptors in Human Cultured Lymphocytes and Peripheral Monocytes, Blecher, M., Ed., New York, Marcel Dekker, Inc, 301-330 (1976)]. Cell viability, determined by exclusion of trypan blue, was greater than 90% in each experiment. Triplicate tubes were prepared, each set containing 100 μl of assay buffer, human insulin, human proinsulin, or a compound of this invention, 200 μl 125 I-insulin (final concentration 1-2×10 -11 M), and 200 μl cells (about 500,000 cells). Incubations were carried out in 1.5 ml microfuge tubes at 15° C. for two hours. Concentrations of stock solutions containing insulin, proinsulin, or compound of this invention used in the binding studies were established by amino acid analysis and by their absorbance at 276 nm. The cells were resuspended during the assay every 30 minutes by inverting the tubes several times. At the end of the incubation, the tubes were centrifuged for one minute in a Beckman Microfuge, the supernatant was aspirated, the tips of the tubes containing the cell pellet were excised, and the radioactivity was measured.
The results from the foregoing are provided in Table I following.
TABLE I______________________________________IM-9 Radioreceptor Assay RelativeCompound ED.sub.50 ( --M) Potency______________________________________Human Insulin .sup. 4.27 ± 0.3 × 10.sup.-10 70Human Proinsulin 2.97 ± 0.2 × 10.sup.-8 1(65-Al split)HPI 1.93 ± 0.3 × 10.sup.-9 15des(64,65)HPI 2.13 ± 0.2 × 10.sup.-9 14des(57-65)HPI 2.05 ± 0.1 × 10.sup.-9 15______________________________________
B. Isolated Fat Cell Radioreceptor Assay
Isolated fat cells were prepared by a modification [Huber, C. T., Solomon, S. S., and Duckworth, W. C., J. Clin. Invest. 65, 461-468 (1980)] of the method described in Rodbell, M., J. Biol. Chem. 239, 375-380 (1964). All incubations were in Krebs-Ringer-Hepes (KRH) buffer, pH 7.4, with 4% bovine serum albumin (BSA) in a total volume of 2 ml. The fat cells were incubated at 15° C. for two hours with 125 I-labeled insulin (1-2×10 -11 M) and, at a selected concentration, with buffer or human insulin or human proinsulin or a compound of this invention. At selected times, triplicate 300 μl aliquots were removed and added to microfuge tubes containing 100 μl dinonyl phthalate [see Gliemann, J., Osterlind, K., Vinten, J., and Gammeltoft, S., Biochem. Biophys. Acta. 286, 1-9 (1972)]. After centrifugation for one minute in a microfuge, the tubes were cut through the oil layer, and the cell pellet was counted using a gamma counter to determine binding. Degradation of the 125 I-labeled insulin was determined by addiing the buffer layer from the microfuge tube to ice-cold KRH buffer followed immediately by sufficient trichloroacetic acid to give a final concentraton of 5%.
The results from the foregoing are provided in Table II following.
TABLE II______________________________________Isolated Fat Cell Radioreceptor Assay RelativeCompound ED.sub.50 ( --M) Potency______________________________________Human Insulin 1.43 ± 0.2 × 10.sup.-9 178Human Proinsulin 2.55 ± 0.6 × 10.sup.-7 1(65-Al split)HPI 9.91 ± 1.1 × 10.sup.-9 26des(64,65)HPI 1.16 ± 0.1 × 10.sup.-8 22des(57-65)HPI 0.94 ± 0.06 × 10.sup.-8 27______________________________________
C. Biological Activity in Isolated Rat Adipocytes
Adipocytes were prepared from epididymal fat pads by a modification (Huber, supra) of the collagenase digestion procedure of Rodbell, supra. Krebs-Ringer-HEPES (KRH) buffer, pH 7.4, containing 4% bovine serum albumin and 0.55 mM glucose was used in all isolation and incubation steps.
Approximately 2×10 5 adipocytes were incubated in one ml of buffer with 125 I-(A14) pork insulin and varying concentrations of unlabeled human insulin, human proinsulin, or a compound of this invention. Incubations were conducted at 15° C. for 4.5 hrs. At the end of the incubation period, triplicate samples were withdrawn for determination of binding (cell-associated radioactivity) as described in Frank, B. H., Peavy, D. E., Hooker, C. S., and Duckworth, W. C., Diabetes 32, 705-711 (1983). At the 15° C. temperature of the incubation, no degradation of the tracer insulin was detectable. Samples were counted with a Tracor Analytic Model 1285 gamma scintillation spectrometer with a counting efficiency of 85%.
Biological activity was assessed according to the method of Moody, A. J., Stan, M. A., Stan, M., and Glieman, J., Horm. Metab. Res. 6, 12-16 (1974) by monitoring the incorporation of 2- 3 H-glucose in total fat cell lipid. Cells were incubated with varying concentrations of cold human insulin, human proinsulin, or a compound of this invention at 37° for 1 hr, and the reaction then was terminated by the addition of 10 ml of Liquifluor (New England Nuclear). Radioactivity was determined in a Searle Isocap 300 liquid scintillation counter at an efficiency of approximately 30%. Blanks were prepared in which the scintillation fluid was added to the vials prior to the addition of cells. The average counts obtained from these vials were subtracted from those observed in all other samples.
Competitive binding curves and biological activity dose-response curves were analyzed using the PREFIT and ALLFIT programs [DeLean, A., Munson, P. J., and Rodbard, D., Am. J. Physiol. 235, E97-E102 (1978)] based on a four-parameter logistic model. These analyses indicated the concentration of insulin or proinsulin necessary to produce a half-maximal response, as well as the maximal and minimal values. All values are presented as the mean ± SEM.
The results from the foregoing are provided in Table III following.
TABLE III______________________________________Biological Activity in Isolated Rat Adipocytes RelativeCompound ED.sub.50 ( --M) Potency______________________________________Human Insulin 5.32 ± 0.7 × 10.sup.-11 233Human Proinsulin 1.24 ± 0.2 × 10.sup.-8 1(65-Al split)HPI 6.56 ± 0.9 × 10.sup.-10 19des(64,65)HPI 6.62 ± 0.3 × 10.sup.-10 19des(57-65)HPI 6.25 ± 0.3 × 10.sup.-10 20______________________________________ | A class of compounds having insulin-like activity is described. These compounds have the formula ##STR1## in which X is --OH, -Ala-Leu-Glu-Gly-Ser-Leu-Gln-OH, or -Ala-Leu-Glu-Gly-Ser-Leu-Gln-Lys-Arg-OH. | 8 |
FIELD OF THE INVENTION
[0001] The invention includes therapeutic compositions and methods, such as peptide cancer chemotherapeutic agents.
BACKGROUND OF THE INVENTION
[0002] Gangliosides are cell surface glycosphingolipids containing one or more sialic acid residues. It has been suggested that gangliosides may be localized within detergent-resistant cell membrane microdomains termed “rafts”, which may provide the environment for some proteins to function by bringing together adapter molecules, modifiers, substrates, or cofactors that would be otherwise too distant or too dilute to form complexes and activate a signal cascade. However, little has been proposed regarding the possible mechanism of action of gangliosides in signal transduction.
[0003] Ganglioside GD2 is reportedly expressed at low levels in certain neuronal populations, but is highly prevalent in many types of tumors (neuroblastoma, melanoma, small cell carcinoma of the lung, gliomas, soft tissue sarcomas and B cell lymphoma).
[0004] The extracellular matrix component Tenascin-R was described recently as a natural ligand for GD2 (Probstmeier et al., 1999). However, relatively little is known about the biological function(s) of GD2 and the functional nature of its interaction with ligands such as Tenascin-R.
[0005] GD2 has been extensively studied as a tumor marker and is used clinically as a target for antibody-mediated therapy (e.g. anti-GD2 mAb 3F8) (Cheung et al., 1985). However, anti-GD2 mAb 3F8 applied therapeutically to patients causes acute and transient pain immediately after administration. Anti-GD2 mAb 3F8-based therapeutics have been suggested for use in a wide range of cancer therapeutics and diagnostics, including neuroblastoma and leptomeningeal cancer. For example, 131 I-labeled anti-GD2 3F8 monoclonal antibody has been used in targeted radioimmunotherapy (dosed at 20 mCi/kg) in conjunction with immunotherapy with 400 mg/m2 unlabeled/unmodified 3F8. Similarly, granulocyte-macrophage colony-stimulating factor (GM-CSF) has been used in conjunction with anti-GD2 monoclonal antibody 3F8 in the treatment of patients with neuroblastoma.
SUMMARY OF THE INVENTION
[0006] In one aspect, the invention provides GD2 ligands of Formula I:
Z 1 -X 1 —X 2 —X 3 —X 4 —X 5 —X 6 —X 7 —X 8 —X 9 —X 10 —X 11 —X 12 —X 13 -Z 2 (I)
wherein X 1 is absent or Y or an analogue thereof; X 2 is absent or C or an analogue thereof; X 3 is G or Y or an analogue thereof; X 4 is G or C or Y or an analogue thereof; X 5 is I or C or an analogue thereof; X 6 is T or A or an analogue thereof; X 7 is N or an analogue thereof; X 8 is Y or an analogue thereof; X 9 is N or G or an analogue thereof; X 10 is S or C or V or T or an analogue thereof; X 11 is A or C or Y or H or S or an analogue thereof; X 12 is absent or L or C or Y or an analogue thereof; X 13 is absent or M or Y or an analogue thereof; Z 1 is an N-terminal group of the formula H2N—, RHN— or, RRN—; Z 2 is a C-terminal group of the formula —C(O)OH, —C(O)R, —C(O)OR, —C(O)NHR, —C(O)NRR; R at each occurrence is independently selected from (C 1 -C 6 ) alkyl, (C 1 -C 6 ) alkenyl, (C 1 -C 6 ) alkynyl, substituted (C 1 -C 6 ) alkyl, substituted (C 1 -C 6 ) alkenyl, or substituted (C 1 -C 6 ) alkynyl; and wherein “—” is a covalent linkage.
[0025] In alternative embodiments, the invention provides substantially pure synthetic GD2 ligands or recombinant GD2 ligands having a domain of Formula II:
—X 1 —X 2 —X 3 —X 4 —X 5 —X 6 —X 7 —X 8 —X 9 —X 10 —X 11 —X 12 —X 13 — (II)
wherein X 1 is absent or Y or an analogue thereof; X 2 is absent or C or an analogue thereof; X 3 is G or Y or an analogue thereof; X 4 is G or C or Y or an analogue thereof; X 5 is I or C or an analogue thereof; X 6 is T or A or an analogue thereof; X 7 is N or an analogue thereof; X 8 is Y or an analogue thereof; X 9 is N or G or an analogue thereof; X 10 is S or C or V or T or an analogue thereof; X 11 is A or C or Y or H or S or an analogue thereof; X 12 is absent or L or C or Y or an analogue thereof; X 13 is absent or M or Y or an analogue thereof; and wherein “—” is a covalent linkage.
[0041] In one aspect, the invention provides recombinant proteins having domains of the invention, wherein the domain is capable of mediating binding of the recombinant protein to GD2. For example, recombinant T-cell receptors having the domains of the invention may be provided in transformed T-cell lines, such as cytotoxic T-cells (a “cytotoxic T lymphocyte” or “CTL” is an immune system cell that recognises epitopes presented by class I MHC molecules through its TCR.). Transformed T-cell lines of the invention may for example be used to treat diseases such as cancers having pathological tissues characterized by expression of GD2 (similar to an approach described in United States Patent Application 20020018783 A1, published in the name of Sadelain, M. et al. on Feb. 14, 2002, incorporated herein by reference).
[0042] The GD2 ligands of the invention may further comprise a cyclic linkage between any two of X 1 through X 13 . In alternative embodiments, the GD2 ligands of the invention, or the domains of the invention, may be selected from the group consisting of: GGITNYNSALM; YCGGITNYNSACY; YCITNYNSCY; YCGGITNYNCY; YCTNYGVHCY; YCTNYGVCY; GGIANYNTS; YCGGIANYNCY; YCGGIANYNTSCY; and, YCIANYNTCY. In some embodiments, known GD2 ligands such as mAb 3F8 and tenascin-R are specifically excluded from the genus of claimed ligands in the present invention. However, in some embodiments, small molecule derivatives and analogs of known ligands (such as small peptides or peptidomimetics of the complementarity determining region of mAbs) are not excluded.
[0043] The invention also provides methods of treating a subject having a disease wherein disease cells express GD2, the method comprising administering to the subject an effective amount of the GD2 ligands of the invention. Also provided are methods of diagnosis of a disease wherein disease cells express GD2, comprising determining whether a cell from a subject binds to a GD2 ligand of the invention. The diagnostic and therapeutic methods of the invention may be carried out in vitro or in vivo.
[0044] In alternative embodiments, the GD2 ligands of the invention may be used with other therapeutic compounds, such as an effective amount of granulocyte-macrophage colony-stimulating factor. The invention provides commercial packages comprising the GD2 ligands of the invention, together with instructions for using the GD2 ligands to modulate GD2 activity or to detect cells expressing GD2.
[0045] Table 1 sets out the sequences of a number of alternative GD2 ligands or GD2 binding domains of the invention. Structure activity relationship (SAR) and deletion analysis demonstrate that some substitutions are allowed and that peptide cyclization enhances activity (peptides marked by * are inactive)
TABLE 1 Alternative domains/peptides of the Invention G G I T N Y N S A L M Y C G G I T N Y N S A C Y Y C I T N Y N S C Y Y C G G I T N Y N C Y Y C T N Y G V H C Y * Y C T N Y G V C Y * G G I A N Y N T S * Y C G G I A N Y N C Y Y C G G I A N Y N T S C Y Y C I A N Y N T C Y X 1 X 2 X 3 X 4 X 5 X 6 X 7 X 8 X 9 X 10 X 11 X 12 X 13
[0046] The invention further provides commercial packages comprising a GD2 ligand, together with instructions for using the GD2 ligand, for example by administering the GD2 ligand to a patient in need of such treatment.
[0047] In alternative embodiments, the invention provides methods of screening to identify a GD2 ligand. For example, such screening methods may involve:
a) Administering a putative GD2 ligand (such as a polypeptide derived from Tenascin-R) to a system having a GD2 moiety and a p56 Lck moiety available for association (such as a cell expressing GD2 and p56 Lck ); and, b) Measuring an association between the GD2 and the p56 Lck moieties in the system, for example by determining a kinase activity of the p56 Lck moiety. In further alternative embodiments, the invention may include: c) Measuring an association between the GD2 and the CD45 moieties in the system, for example by determining the phosphatase activity of the CD45 moiety.
[0051] In further alternative embodiments, the forgoing method further comprises:
b) Administering a putative GD2 ligand to a system having a GD2 moiety and a phosphatase such as CD45; and c) Measuring an association or functional relationship between GD2 and the phosphatase d) A competitive screening assay where test compounds (e.g. a combinatorial library) are used to displace any of the GD2 ligands described herein e) A competitive screening assay where any of the GD2 ligands described herein are used to displace test compounds
[0056] In some embodiments, the putative GD2 ligand may for example comprise a polypeptide or a non-peptidic analog such as a peptidomimetic that displays the same pharmacophore or has similar side chain functional groups.
BRIEF DESCRIPTION OF THE DRAWINGS
[0057] FIG. 1 is the full-length protein sequence of Homo sapiens tenascin-R (restrictin, janusin), from GenBank Accession XP — 040550, with a region identified in bold within a box that is identified in accordance with one aspect of the invention as a GD2 binding region. One aspect of the invention provides alternative tenascin-R proteins in which the GD2 binding region has been altered, for example to modulate the strength of the interaction between GD2 and the tenascin-R protein.
[0058] FIG. 2 shows data relating to the co-immunoprecipitation of GD2 and p56 Lck :
[0059] ( a ) R1.1 and EL4 GD2 positive cell lysates were subjected to immunoprecipitation with anti-GD2 mAb 3F8 or control mouse IgG (mlg). Presence of p56 Lck protein in the immunoprecipitates was evaluated by western blotting. p56 Lck can be immunoprecipitated by mAb 3F8 in EL4 GD2 positive cells (lane 7) but not in R1.1 cells (lane 5). Total cell lysates were used as a control for p56 Lck detection (lane 1 and 2).
[0060] ( b ) and ( c ) R1.1, EL4 GD2 negative and EL4 GD2 positive cell lysates were subjected to immunoprecipitation with anti-GD2 mAb 3F8, GM1-binding cholera toxin B, anti-p56 Lck mAb 3A5 and anti-Zap-70 mAb LR. Presence of p56 Lck kinase activity in the immunoprecipitates was evaluated by in vitro kinase assay with the p56 Lck -specific substrates Sam68 and Gap p62. The data in FIG. 2 ( b ) shows that p56 Lck kinase activity can be immunoprecipitated by mAb 3F8 in EL4 GD2 positive cells (lane 1) but not in EL4 GD2 negative cells (lane 4). The data in FIG. 2 ( c ) shows that p56 Lck kinase activity can be immunoprecipitated by mAb 3F8 in EL4 GD2 positive cells (lane 1) but by cholera toxin B in R1.1 cells (lane 4).
[0061] ( d ) R1.1 and EL4 GD2 positive cell lysates were subjected to immunoprecipitation with anti-GD2 mAb 3F8, GM1-binding cholera toxin B and anti-p56 Lck mAb 3A5. Presence of gangliosides GD2 and GM1 in the immunoprecipitates was evaluated by ELISA. Anti-p56 Lck mAb 3A5 can immunoprecipitate GD2 from EL4 GD2 positive cells, but can not immunoprecipitate GM1 from R1.1 cells. Shown are averages±SEM of one representative experiment. n=4 per experiment.
[0062] FIG. 3 shows the effect of gangliosides on the in vitro kinase activity of purified p56 Lck . The kinase activity of p56 Lck was evaluated by measuring the incorporation of 32 PO 4 in a peptidic p56 Lck substrate over time, with or without GD2 or GM1. Presence of GD2, but not GM1, can positively alter the kinetics of p56 Lck kinase activity. Activity standardized to untreated p56 Lck at the 20 minute time point. Shown are averages of 3 to 5 assays±SEM.
[0063] FIG. 4 shows:
[0064] ( a ) the effect of GD2 ligands on p56 Lck phosphorylation. Resting EL4 GD2 positive cells were treated with mAb 3F8 (13 nM) or control mouse IgG (mlg) for the indicated times. After lysis, p56 Lck protein was immunoprecipitated with anti-p56 Lck mAb 3A5 and probed for phosphotyrosine (PY) by western blotting using biotinylated anti-phosphotyrosine mAb 4G10. Anti-GD2 mAb 3F8 can induce tyrosine phosphorylation of p56 Lck within 5 minutes (lane 3) and sustain it for at least 30 minutes (lane 4).
[0065] ( b ) the effect of GD2 ligands on Zap-70 phosphorylation. Resting EL4 GD2 positive cells were treated with mAb 3F8 (13 nM) or control mouse IgG (mlg) for the indicated times. After lysis, Zap-70 protein was immunoprecipitated with anti-Zap-70 mAb LR and probed for phosphotyrosine (PY) by western blotting using anti-phosphotyrosine mAb 4G10. Anti-GD2 mAb 3F8 can induce tyrosine phosphorylation of Zap-70 within 5 minutes (lane 3). c) Effect of GD2 ligands on intracellular calcium concentrations. Resting EL4 GD2 positive cells were treated with mAb 3F8 (13 nM), control mouse IgG (mlg) or the calcium ionophore A23187. Intracellular calcium concentration was evaluated over time by flow cytometry using the calcium-sensitive fluorophore Rhod-2 AM. mAb 3F8 can induce strong, sustainable calcium changes within 5 minutes, while control mouse IgG has no effect. Addition of the p56 Lck inhibitor PP1 partially abolished mAb 3F8's effects.
[0066] Shown are averages of 4 independent assays±SEM.
[0067] FIG. 5 shows the inhibitory effect of GD2 on in vitro CD45 phosphatase activity, particularly when using the pp60 Src C-terminal phosphoregulatory sequence as a substrate. When co-incubated for 20 minutes, GD2 (but not other gangiosides) can drastically inhibit CD45 phosphatase activity, as measured by the colorimetric quantification of released free phosphate.
[0068] FIG. 6 shows the inhibitory effect of GD2 on ex vivo CD45 phosphatase activity, measured by the dephosphorylation of tyrosine 505 on p56 Lck . EL4 GD2 positive and EL4 GD 2 negative cells were treated with control mlg, anti-GD2 antibody 3F8 or anti-CD3 antibody 145-2C11 cross-linked with anti-hamster antibody G94-56 for 20 minutes at 37° C. After lysis, p56 Lck was immunoprecipitated with anti-p56 Lck 3A5 coated beads and probed for phosphotyrosine at position 505 by western blotting with anti-PY505 antibody. EL4 GD2 positive cells treated with anti-CD3 fail to induce dephosphorylation of p56 Lck at tyrosine 505 (lane 3), while EL4 GD 2 negative cells show a marked dephosphorylation with the same treatment (lane 6), indicating that the presence of GD2 inhibits the CD45 phosphatase responsible for tyrosine 505 dephosphorylation. GD2 ligands such as anti-GD2 antibody 3F8, are able to relieve CD45 of its GD2-mediated inhibition (lane 2).
[0069] FIG. 7 shows data from soft-agar clonogenic assays. EL4 GD2 positive and EL4 GD 2 negative cells were cultured in soft agar in the presence or absence of anti-GD2 antibody 3F8 (2 plates per sample).
[0070] ( a ) Total number of visible colonies. EL4 GD2 positive cells show reduced colony formation compared to EL4 GD2 negative cells. Anti-GD2 antibody 3F8 abolishes EL4 GD2 positive cells growth but does not affect EL4 GD2 negative cells.
[0071] ( b ) Typical EL4 GD2 positive and EL4 GD2 negative colonies. EL4 GD2 negative colonies contain many more cells than EL4 GD2 positive colonies. Bar=100 micrometers.
[0072] FIG. 8 shows data from tumorigenic assays. EL4 GD2 positive and EL4 GD2 negative cells were injected intraperitoneally in a) nude Balb/c and b) syngeneic C57BL/g mice. EL4 GD2 negative injected animals (left) show important ascitic tumors, whereas EL4 GD2 positive injected animals (right) show localized solid tumors (circled area). Bar=1 mm.
DETAILED DESCRIPTION OF THE INVENTION
[0073] In one aspect, the invention provides selective artificial ligands of GD2. In some embodiments, such ligands may be used to modulate ganglioside GD2 signal transduction selectively in the tissue where it is normally expressed, particularly in pathways that can be linked to tumorigenic growth or to nociceptive receptors. One aspect of the invention involves the identification of primary and tertiary structures in Tenascin-R that are critical for GD2 binding. In an alternative aspect, the invention demonstrates that a complementarity determining region of anti-GD2 mAb 3F8 is an analogue of Tenascin-R. Small peptide mimics of Tenascin-R and mimics of anti-GD2 mAb 3F8 have accordingly been designed and synthesized as selective ligands of GD2. Alternative ligands may be provided, based on the ligands of the invention, by protein mimicry and antibody mimicry techniques (Saragovi et al., 1992).
[0074] In an alternative aspect of the invention, it is demonstrated that GD2 (but not GM1) associates physically with p56 Lck in vivo, in complexes that are stable to detergent lysis. It is shown that GD2 regulates signal transduction by enhancing p56 Lck enzymatic activity in vitro and by enhancing in vivo phosphorylation of p56 Lck and the p56 Lck substrate Zap70. Accordingly, GD2 ligands of the invention may be used to cause p56 Lck -dependent fluxes in intracellular calcium in live cells, and thereby to modulate a variety of physiological or pathological cellular functions.
[0075] In an alternative aspect of the invention, it is demonstrated that GD2 (but not other gangliosides) can inhibit CD45 phosphatase activity in vitro and ex vivo. Accordingly, GD2 ligands of the invention may be used to antagonize the inhibitory action of GD2 on CD45 in live cells, and thereby to modulate a variety of physiological, immunological or pathological cellular functions.
[0076] In one aspect of the invention, expression of GD2 is shown to alter tumorigenicity in vitro and in vivo. As shown in the Examples, in EL4 clones that are otherwise phenotypically indistinguishable GD2 negative than in GD2 positive cells have equal doubling times, but soft agar colony growth is significantly more efficient in GD2 negative cells. Further, addition of GD2 ligands in this assay causes the apoptotic death of GD2 positive cells. GD2 negative cells are also more tumorigenic in vivo. GD2 positive cells injected intraperitoneally or subcutaneously in syngeneic mice only form solid tumors at the primary site, with little metastasis. In contrast, GD2 negative cells can digest the peritoneal membrane, form viscous, muscin-like ascitic tumors, small solid tumor nodules, and are highly metastatic. Accordingly, in one aspect of the invention cells may be transformed so that they are GD2 positive , and the transformed GD2 positive cells may be treated to GD2 ligands of the invention to mediate cell death, for example by an apoptotic pathway. For example, GD2 negative cancer cells may be transformed by targeted gene therapy techniques, so that the cells become GD2 positive , and the transformed GD2 positive cancer cells may be treated with a GD2 ligand of the invention.
[0077] In alternative aspects, GD2 ligands of the invention may be used to influence or modulate signal transduction in a biologically relevant manner in vitro and in vivo in the treatment of diseases such as cancer and in managing symptoms such as pain.
[0078] In one aspect, the invention provides compounds, such as GD2 ligands, that are purified, isolated or substantially pure. A compound is “substantially pure” when it is separated from the components that naturally accompany it. Typically, a compound is substantially pure when it is at least 60%, more generally 75% or over 90%, by weight, of the total material in a sample. Thus, for example, a polypeptide that is chemically synthesised or produced by recombinant technology will generally be substantially free from its naturally associated components. A nucleic acid molecule is substantially pure when it is not immediately contiguous with (i.e., covalently linked to) the coding sequences with which it is normally contiguous in the naturally occurring genome of the organism from which the DNA of the invention is derived. A substantially pure compound can be obtained, for example, by extraction from a natural source; by expression of a recombinant nucleic acid molecule encoding a polypeptide compound; or by chemical synthesis. Purity can be measured using any appropriate method such as column chromatography, gel electrophoresis, HPLC, etc.
[0079] The term “alkyl” refers to the radical of saturated aliphatic groups, including straight chain alkyl groups, branched-chain alkyl groups, cycloalkyl (alicyclic) groups, alkyl substituted cycloalkyl groups, and cycloalkyl substituted alkyl groups. Typical alkyl groups include, but are not limited to, methyl, ethyl, propyl, isopropyl, butyl, isobutyl, t-butyl, pentyl, isopentyl, hexyl, etc. The alkyl groups can be (C 1 -C 6 ) alkyl, or (C 1 -C 3 ) alkyl. A “substituted alkyl” has substituents replacing a hydrogen on one or more carbons of the hydrocarbon backbone. Such substituents can include, for example, halogen, hydroxyl, carbonyl (such as carboxyl, ketones (including alkylcarbonyl and arylcarbonyl groups), and esters (including alkyloxycarbonyl and aryloxycarbonyl groups)), thiocarbonyl, acyloxy, alkoxyl, phosphoryl, phosphonate, phosphinate, amino, acylamino, amido, amidine, imino, cyano, nitro, azido, sulfhydryl, alkylthio, sulfate, sulfonate, sulfamoyl, sulfonamido, heterocyclyl, aralkyl, or an aromatic or heteroaromatic moiety. The moieties substituted on the hydrocarbon chain can themselves be substituted, if appropriate. For instance, the substituents of a substituted alkyl may include substituted and unsubstituted forms of aminos, azidos, iminos, amidos, phosphoryls (including phosphonates and phosphinates), sulfonyls (including sulfates, sulfonamidos, sulfamoyls and sulfonates), and silyl groups, as well as ethers, alkylthios, carbonyls (including ketones, aldehydes, carboxylates, and esters), —CF 3 , —CN and the like. Exemplary substituted alkyls are described below. Cycloalkyls can be further substituted with alkyls, alkenyls, alkoxys, alkylthios, aminoalkyls, carbonyl-substituted alkyls, —CF 3 , —CN, and the like.
[0080] The terms “alkenyl” and “alkynyl” refer to unsaturated aliphatic groups analogous in length and possible substitution to the alkyls described above, but that contain at least one double or triple bond respectively. An “alkenyl” is an unsaturated branched, straight chain, or cyclic hydrocarbon radical with at least one carbon-carbon double bond. The radical can be in either the cis or trans conformation about the double bond(s). Typical alkenyl groups include, but are not limited to, ethenyl, propenyl, isopropenyl, butenyl, isobutenyl, tert-butenyl, pentenyl, hexenyl, etc. An “alkynyl” is an unsaturated branched, straight chain, or cyclic hydrocarbon radical with at least one carbon-carbon triple bond. Typical alkynyl groups include, but are not limited to, ethynyl, propynyl, butynyl, isobutynyl, pentynyl, hexynyl, etc.
[0081] A “substantially identical” sequence is an amino acid or nucleotide sequence that differs from a reference sequence only by one or more conservative substitutions, as discussed herein, or by one or more non-conservative substitutions, deletion, or insertions located at positions of the sequence that do not destroy the biological function of the test compound. Such a sequence can be at least 60% or 75%, or more generally at least 80%, 85%, 90%, or 95%, or as much as 99% identical at the amino acid or nucleotide level to the sequence used for comparison. Sequence identity can be readily measured using publicly available sequence analysis software (e.g., Sequence Analysis Software Package of the Genetics Computer Group, University of Wisconsin Biotechnology Center, 1710 University Avenue, Madison, Wis. 53705, or BLAST software available from the National Library of Medicine). Examples of useful software include the programs, Pile-up and PrettyBox. Such software matches similar sequences by assigning degrees of homology to various substitutions, deletions, substitutions, and other modifications.
[0082] In alternative embodiments, GD2 ligands can be produced by substitution of either/or (i) side chains, (ii) backbone, or (iii) ionic interaction within a peptide. Additionally, structural or functional analogs can include 1) homologs of the peptidic GD2 ligands generated by peptidomimicry and 2) analogs where the sequence/structure of the GD2 ligands is introduced in a larger protein to convey GD2 binding to that protein.
[0083] In one aspect the invention provides nucleic acids that encode peptide compounds of the invention. Such nucleic acids may be introduced into cells for expression using standard recombinant techniques for stable or transient expression. Nucleic acid molecules of the invention may include any chain of two or more nucleotides including naturally occurring or non-naturally occurring nucleotides or nucleotide analogues.
[0084] Various genes and nucleic acid sequences of the invention may be recombinant sequences. The term “recombinant” means that something has been recombined, so that when made in reference to a nucleic acid construct the term refers to a molecule that is comprised of nucleic acid sequences that are joined together or produced by means of molecular biological techniques. The term “recombinant” when made in reference to a protein or a polypeptide refers to a protein or polypeptide molecule which is expressed using a recombinant nucleic acid construct created by means of molecular biological techniques. The term “recombinant” when made in reference to genetic composition refers to a gamete or progeny or cell or genome with new combinations of alleles that did not occur in the parental genomes. Recombinant nucleic acid constructs may include a nucleotide sequence which is ligated to, or is manipulated to become ligated to, a nucleic acid sequence to which it is not ligated in nature, or to which it is ligated at a different location in nature. Referring to a nucleic acid construct as ‘recombinant’ therefore indicates that the nucleic acid molecule has been manipulated using genetic engineering, i.e. by human intervention. Recombinant nucleic acid constructs may for example be introduced into a host cell by transformation. Such recombinant nucleic acid constructs may include sequences derived from the same host cell species or from different host cell species, which have been isolated and reintroduced into cells of the host species. Recombinant nucleic acid construct sequences may become integrated into a host cell genome, either as a result of the original transformation of the host cells, or as the result of subsequent recombination and/or repair events.
[0085] In one aspect the invention provides antibodies that recognize compounds of the invention, and anti-idiotypic antibodies that in turn recognize such antibodies. The compounds of the invention can be used to prepare antibodies to GD2 ligands using standard techniques of preparation as, for example, described in Harlow and Lane (Antibodies; A Laboratory Manual, Cold Spring Harbor Laboratory, Cold Spring Harbor, N.Y., 1988), or known to those skilled in the art. Antibodies can be tailored to minimise adverse host immune response by, for example, using chimeric antibodies contain an antigen binding domain from one species and the Fc portion from another species, or by using antibodies made from hybridomas of the appropriate species.
[0086] Compounds of the invention can be prepared, for example, by replacing, deleting, or inserting an amino acid residue of a GD2 ligand or domain of the invention, with other conservatived amino acid residues, i.e., residues having similar physical, biological, or chemical properties, and screening for biological function. It is well known in the art that some modifications and changes can be made in the structure of a polypeptide without substantially altering the biological function of that peptide, to obtain a biologically equivalent polypeptide. The peptides, ligands and domains of the present invention also extend to biologically equivalent peptides, ligands and domains that differ from a portion of the sequence of novel ligands of the present invention by conservative amino acid substitutions. As used herein, the term “conserved amino acid substitutions” refers to the substitution of one amino acid for another at a given location in the peptide, where the substitution can be made without substantial loss of the relevant function. In making such changes, substitutions of like amino acid residues can be made on the basis of relative similarity of side-chain substituents, for example, their size, charge, hydrophobicity, hydrophilicity, and the like, and such substitutions may be assayed for their effect on the function of the peptide by routine testing.
[0087] In some embodiments, conserved amino acid substitutions may be made where an amino acid residue is substituted for another having a similar hydrophilicity value (e.g., within a value of plus or minus 2.0), where the following may be an amino acid having a hydropathic index of about −1.6 such as Tyr (−1.3) or Pro (−1.6)s are assigned to amino acid residues (as detailed in U.S. Pat. No. 4,554,101, incorporated herein by reference): Arg (+3.0); Lys (+3.0); Asp (+3.0); Glu (+3.0); Ser (+0.3); Asn (+0.2); Gln (+0.2); Gly (0); Pro (−0.5); Thr (−0.4); Ala (−0.5); His (−0.5); Cys (−1.0); Met (−1.3); Val (−1.5); Leu (−1.8); Ile (−1.8); Tyr (−2.3); Phe (−2.5); and Trp (−3.4).
[0088] In alternative embodiments, conserved amino acid substitutions may be made where an amino acid residue is substituted for another having a similar hydropathic index (e.g., within a value of plus or minus 2.0). In such embodiments, each amino acid residue may be assigned a hydropathic index on the basis of its hydrophobicity and charge characteristics, as follows: lie (+4.5); Val (+4.2); Leu (+3.8); Phe (+2.8); Cys (+2.5); Met (+1.9); Ala (+1.8); Gly (−0.4); Thr (−0.7); Ser (−0.8); Trp (−0.9); Tyr (−1.3); Pro (−1.6); His (−3.2); Glu (−3.5); Gln (−3.5); Asp (−3.5); Asn (−3.5); Lys (−3.9); and Arg (−4.5).
[0089] In alternative embodiments, conserved amino acid substitutions may be made where an amino acid residue is substituted for another in the same class, where the amino acids are divided into non-polar, acidic, basic and neutral classes, as follows: non-polar Ala, Val, Leu, Ile, Phe, Trp, Pro, Met; acidic: Asp, Glu; basic: Lys, Arg, His; neutral: Gly, Ser, Thr, Cys, Asn, Gln, Tyr.
[0090] Conservative amino acid changes can include the substitution of an L-amino acid by the corresponding D-amino acid, by a conservative D-amino acid, or by a naturally-occurring, non-genetically encoded form of amino acid, as well as a conservative substitution of an L-amino acid. Naturally-occurring non-genetically encoded amino acids include beta-alanine, 3-amino-propionic acid, 2,3-diamino propionic acid, alpha-aminoisobutyric acid, 4-amino-butyric acid, N-methylglycine(sarcosine), hydroxyproline, omithine, citrulline, t-butylalanine, t-butylglycine, N-methylisoleucine, phenylglycine, cyclohexylalanine, norleucine, norvaline, 2-napthylalanine, pyridylalanine, 3-benzothienyl alanine, 4-chlorophenylalanine, 2-fluorophenylalanine, 3-fluorophenylalanine, 4-fluorophenylalanine, penicillamine, 1,2,3,4-tetrahydro-isoquinoline-3-carboxylix acid, beta-2-thienylalanine, methionine sulfoxide, homoarginine, N-acetyl lysine, 2-amino butyric acid, 2-amino butyric acid, 2,4,-diamino butyric acid, p-aminophenylalanine, N-methylvaline, homocysteine, homoserine, cysteic acid, epsilon-amino hexanoic acid, delta-amino valeric acid, or 2,3-diaminobutyric acid.
[0091] In alternative embodiments, conservative amino acid changes include changes based on considerations of hydrophilicity or hydrophobicity, size or volume, or charge. Amino acids can be generally characterized as hydrophobic or hydrophilic, depending primarily on the properties of the amino acid side chain. A hydrophobic amino acid exhibits a hydrophobicity of greater than zero, and a hydrophilic amino acid exhibits a hydrophilicity of less than zero, based on the normalized consensus hydrophobicity scale of Eisenberg et al. ( J. Mol. Bio. 179:125-142, 1984). Genetically encoded hydrophobic amino acids include Gly, Ala, Phe, Val, Leu, Ile, Pro, Met and Trp, and genetically encoded hydrophilic amino acids include Thr, His, Glu, Gln, Asp, Arg, Ser, and Lys. Non-genetically encoded hydrophobic amino acids include t-butylalanine, while non-genetically encoded hydrophilic amino acids include citrulline and homocysteine.
[0092] Hydrophobic or hydrophilic amino acids can be further subdivided based on the characteristics of their side chains. For example, an aromatic amino acid is a hydrophobic amino acid with a side chain containing at least one aromatic or heteroaromatic ring, which may contain one or more substituents such as —OH, —SH, —CN, —F, —Cl, —Br, —I, —NO 2 , —NO, —NH 2 , —NHR, —NRR, —C(O)R, —C(O)OH, —C(O)OR, —C(O)NH 2 , —C(O)NHR, —C(O)NRR, etc., where R is independently (C 1 -C 6 ) alkyl, substituted (C 1 -C 6 ) alkyl, (C 1 -C 6 ) alkenyl, substituted (C 1 -C 6 ) alkenyl, (C 1 -C 6 ) alkynyl, substituted (C 1 -C 6 ) alkynyl, (C 5 -C 20 ) aryl, substituted (C 5 -C 20 ) aryl, (C 6 -C 26 ) alkaryl, substituted (C 6 -C 26 ) alkaryl, 5-20 membered heteroaryl, substituted 5-20 membered heteroaryl, 6-26 membered alkheteroaryl or substituted 6-26 membered alkheteroaryl. Genetically encoded aromatic amino acids include Phe, Tyr, and Tryp, while non-genetically encoded aromatic amino acids include phenylglycine, 2-napthylalanine, beta-2-thienylalanine, 1,2,3,4-tetrahydro-isoquinoline-3-carboxylic acid, 4-chlorophenylalanine, 2-fluorophenylalanine3-fluorophenylalanine, and 4-fluorophenylalanine.
[0093] An apolar amino acid is a hydrophobic amino acid with a side chain that is uncharged at physiological pH and which has bonds in which a pair of electrons shared in common by two atoms is generally held equally by each of the two atoms (i.e., the side chain is not polar). Genetically encoded apolar amino acids include Gly, Leu, Val, lie, Ala, and Met, while non-genetically encoded apolar amino acids include cyclohexylalanine. Apolar amino acids can be further subdivided to include aliphatic amino acids, which is a hydrophobic amino acid having an aliphatic hydrocarbon side chain. Genetically encoded aliphatic amino acids include Ala, Leu, Val, and Ile, while non-genetically encoded aliphatic amino acids include norleucine.
[0094] A polar amino acid is a hydrophilic amino acid with a side chain that is uncharged at physiological pH, but which has one bond in which the pair of electrons shared in common by two atoms is held more closely by one of the atoms. Genetically encoded polar amino acids include Ser, Thr, Asn, and Gln, while non-genetically encoded polar amino acids include citrulline, N-acetyl lysine, and methionine sulfoxide.
[0095] An acidic amino acid is a hydrophilic amino acid with a side chain pKa value of less than 7. Acidic amino acids typically have negatively charged side chains at physiological pH due to loss of a hydrogen ion. Genetically encoded acidic amino acids include Asp and Glu. A basic amino acid is a hydrophilic amino acid with a side chain pKa value of greater than 7. Basic amino acids typically have positively charged side chains at physiological pH due to association with hydronium ion. Genetically encoded basic amino acids include Arg, Lys, and His, while non-genetically encoded basic amino acids include the non-cyclic amino acids omithine, 2,3,-diaminopropionic acid, 2,4-diaminobutyric acid, and homoarginine.
[0096] The above classifications are not absolute and an amino acid may be classified in more than one category. In addition, amino acids can be classified based on known behaviour and or characteristic chemical, physical, or biological properties based on specified assays or as compared with previously identified amino acids. Amino acids can also include bifunctional moieties having amino acid-like side chains.
[0097] Conservative changes can also include the substitution of a chemically derivatised moiety for a non-derivatised residue, by for example, reaction of a functional side group of an amino acid. Thus, these substitutions can include compounds whose free amino groups have been derivatised to amine hydrochlorides, p-toluene sulfonyl groups, carbobenzoxy groups, t-butyloxycarbonyl groups, chloroacetyl groups or formyl groups. Similarly, free carboxyl groups can be derivatized to form salts, methyl and ethyl esters or other types of esters or hydrazides, and side chains can be derivatized to form O-acyl or O-alkyl derivatives for free hydroxyl groups or N-im-benzylhistidine for the imidazole nitrogen of histidine. Peptide analogues also include amino acids that have been chemically altered, for example, by methylation, by amidation of the C-terminal amino acid by an alkylamine such as ethylamine, ethanolamine, or ethylene diamine, or acylation or methylation of an amino acid side chain (such as acylation of the epsilon amino group of lysine). Peptide analogues can also include replacement of the amide linkage in the peptide with a substituted amide (for example, groups of the formula —C(O)—NR, where R is (C 1 -C 6 ) alkyl, (C 1 -C 6 ) alkenyl, (C 1 -C 6 ) alkynyl, substituted (C 1 -C 6 ) alkyl, substituted (C 1 -C 6 ) alkenyl, or substituted (C 1 -C 6 ) alkynyl) or isostere of an amide linkage (for example, —CH 2 NH—, —CH 2 S, —CH 2 CH 2 —, —CH═CH— (cis and trans), —C(O)CH 2 —, —CH(OH)CH 2 —, or —CH 2 SO—).
[0098] The GD2 ligands, peptides and domains of the invention may be covalently linked, for example, by polymerisation or conjugation, to form homopolymers or heteropolymers. Spacers and linkers, typically composed of small neutral molecules, such as amino acids that are uncharged under physiological conditions, can be used. Linkages can be achieved in a number of ways. For example, cysteine residues can be added at the peptide termini, and multiple peptides can be covalently bonded by controlled oxidation. Alternatively, heterobifunctional agents, such as disulfide/amide forming agents or thioether/amide forming agents can be used. The compound can also be linked to a lipid-containing molecule or peptide that can enhance a T cell response. The compound can also be constrained, for example, by having cyclic portions.
[0099] Peptides or peptide analogues can be synthesised by standard chemical techniques, for example, by automated synthesis using solution or solid phase synthesis methodology. Automated peptide synthesisers are commercially available and use techniques well known in the art. Peptides and peptide analogues can also be prepared using recombinant DNA technology using standard methods.
[0100] Compounds of the invention can be provided alone or in combination or conjugation with other compounds (for example, toxins, growth factors, anti-apoptotic agents, small molecules, peptides, or peptide analogues), in the presence of a liposome, an adjuvant, or any pharmaceutically acceptable carrier, in a form suitable for administration to humans. Conventional pharmaceutical practice may be employed to provide suitable formulations or compositions to administer the compounds to patients suffering from diseases such as cancer. Any appropriate route of administration may be employed, for example, parenteral, intravenous, subcutaneous, intramuscular, intracranial, intraorbital, ophthalmic, intraventricular, intracapsular, intraspinal, intracisternal, intraperitoneal, intranasal, aerosol, or oral administration. Therapeutic formulations may be in the form of liquid solutions or suspensions; for oral administration, formulations may be in the form of tablets or capsules; and for intranasal formulations, in the form of powders, nasal drops, or aerosols.
[0101] Formulations for parenteral administration may, for example, contain excipients, sterile water, or saline, polyalkylene glycols such as polyethylene glycol, oils of vegetable origin, or hydrogenated napthalenes. Biocompatible, biodegradable lactide polymer, lactide/glycolide copolymer, or polyoxyethylene-polyoxypropylene copolymers may be used to control the release of the compounds. Other potentially useful parenteral delivery systems for modulatory compounds include ethylene-vinyl acetate copolymer particles, osmotic pumps, implantable infusion systems, and liposomes. Formulations for inhalation may contain excipients, for example, lactose, or may be aqueous solutions containing, for example, polyoxyethylene-9-lauryl ether, glycocholate and deoxycholate, or may be oily solutions for administration in the form of nasal drops, or as a gel.
[0102] If desired, treatment with a compound according to the invention may be combined with more traditional therapies for the disease such as, for example, surgery or chemotherapy.
[0103] For therapeutic or prophylactic compositions, the compounds may be administered to an individual in an amount sufficient to induce the destruction of cells (such as cancer cells) or to stop or slow the destruction of cells (such as in neuroprotective treatments or treatment of pain). Amounts considered sufficient will vary according to the specific compound used, the mode of administration, the stage and severity of the disease, the age, sex, and health of the individual being treated, and concurrent treatments. As a general rule, however, dosages can range from about 1 microgram to about 100 mg per kg body weight of a patient for an initial dosage, with subsequent adjustments depending on the patient's response.
[0104] In the case of vaccine formulations, an immunogenically effective amount of a compound of the invention can be provided, alone or in combination with other compounds, with an adjuvant, for example, Freund's incomplete adjuvant or aluminum hydroxide. The compound may also be linked with a carrier molecule, such as bovine serum albumin or keyhole limpet hemocyanin to enhance immunogenicity.
[0105] In general, compounds of the invention should be used without causing substantial toxicity. Toxicity of the compounds of the invention can be determined using standard techniques, for example, by testing in cell cultures or experimental animals and determining the therapeutic index, i.e., the ratio between the LD50 (the dose lethal to 50% of the population) and the LD100 (the dose lethal to 100% of the population). In some circumstances however, such as in severe disease conditions, it may be necessary to administer substantial excesses of the compositions.
[0106] The following examples are intended to illustrate various embodiments and aspects of the invention, and do not limit the invention in any way.
EXAMPLES
[0107] Methods
[0108] Cells: EL4 murine lymphoma and R1.1 murine lymphoma were grown in RPMI 1640 medium (Life Technologies) supplemented with 5% fetal bovine serum, 2 mM glutamine, 10 mM Hepes and penicillin/streptomycin at 37° C. in 5% CO 2 humidified atmosphere. A GD2-negative mutant of EL4 was obtained after subcloning of EL4 cells resistant to culture with anti-GD2 mAb 3F8 and rabbit complement.
[0109] Flow cytometry: 10 5 cells in 50 μl FACS buffer (PBS, 0.5% BSA, 0.05% NaN 3 ) were stained for 30 minutes on ice with the following ligands: for GD2, fluorescein isothiocyanate (FITC)-conjugated anti-GD2 mAb 3F8; for GM1, FITC-conjugated cholera toxin B subunit (Sigma); for GM2, rabbit anti-GM2 mAb NANA (Matreya) followed by FITC-conjugated anti-rabbit antibody (Sigma); for GD3, mouse anti-GD3 mAb (Pharmingen) followed by FITC conjugated anti-mouse antibody (Sigma). Cells were washed twice with FACS buffer and analyzed on a flow cytometer (Becton-Dickinson) using CellQuest software.
[0110] Detection of GD2 or GM1 by ELISA: 12.5 ng/well of ganglioside (GD2, Advanced Immunochemicals or GM1) were immobilized by drying onto PVC 96-well plates (Falcon), followed by blocking with PBS-0.5% BSA for one hour. Then, anti-GD2 mAb 3F8 or biotin-CTB were added for 10 minutes. The plate was washed three times with PBS-0.5% BSA and incubated 60 minutes with horseradish peroxidase (HRP)-conjugated anti-mouse antibody or HRP-conjugated-avidin. After three washes with PBS-0.5% BSA and two with PBS, the colorimetric substrate ABTS was added and the plate read at 414 nm on a Biorad 550 plate reader.
[0111] Co-immunoprecipitation of GD2 and p56 Lck : cells (5×10 6 per sample) were washed in PBS, resuspended in 1 ml lysis buffer (150 mM NaCl, 10 mM sodium phosphate pH 7.2, 2 mM EDTA, 50 mM NaF, 1% CHAPS, 200 μM sodium orthovanadate, 1 mM PMSF, 100 μM leupeptin, 1 mM benzamidine, 300 nM aprotinin, 500 nM soybean trypsin inhibitor) and incubated 30 minutes at 4° C. Supernatants were collected from lysates after centrifugation (16000 g for 15 minutes at 4° C.). Immunoprecipitations were carried out overnight at 4° C. using 50 μl protein-G sepharose (Sigma) with either 5 μg of anti-GD2 mAb 3F8 or anti-p56 Lck mAb 3A5 (Santa Cruz Biotechnology) or control IgG; or with 50 μl avidin-agarose (Sigma) and 5 μg of biotin-CTB which is specific for GM1 gangliosides. Immunoprecipitates were washed 5 times with 1 ml of cold lysis buffer containing decreasing concentration of CHAPS detergent and samples were extracted with reduced Laemmli buffer. Samples were then used for western blot analysis (see below), or lipids from the samples were isolated for ganglioside quantification by ELISA (see above).
[0112] Biochemical analysis: Western blotting: the immunoprecipitated samples were fractionated in SDS-PAGE and transferred to membranes, p56 Lck immunoblotting was done using rabbit polyclonal anti-p56 Lck antibody. Tyrosine phosphorylation of p56 Lck and Zap70: cells (5×10 6 per sample) were washed with PBS, resuspended in 5 ml protein-free hybridoma medium containing 0.2% BSA and allowed to rest for 60 minutes at 37° C. to lower baseline kinase activity. Then, 10 μg Anti-GD2 mAb 3F8 (13 nM concentration) or non-specific mouse IgG were added for 5 and 20 minutes. Samples were then washed in cold PBS, detergent solubilized in lysis buffer and immunoprecipitated using 5 pg of anti-p56 Lck mAb 3A5 (Santa Cruz Biotechnology) or anti-Zap70 mAb LR (Santa Cruz Biotechnology). Samples were then analyzed by western blotting using anti-phosphotyrosine mAb 4G10. In vitro p56 Lck kinase activity: p56 Lck immunoprecipitates were incubated for 20 minutes at 37° C. with p56 Lck -specific substrates GAP p62 or Sam68 in a kinase reaction buffer (10 mM MnCl 2 , 20 mM Tris-HCl pH 7.4, 2.5 μM ATP, 20 μCi [γ- 32 P]ATP). The reaction was stopped by addition of reduced Laemmli buffer and boiling. Phosphorylation of p56 Lck substrates was visualized and quantified by SDS-PAGE followed by analysis on a Storm 840 phosphorimager with ImageQuant software.
[0113] Effect of exogenous GD2 on p56 Lck in vitro kinase assay: chromatographically purified p56 Lck tyrosine kinase (Upstate Biotechnology) was incubated on ice for 10 minutes in kinase buffer (100 mM Tris-HCl, pH 7.2, 125 mM MgCl 2 , 25 mM MnCl 2 , 2 mM EGTA, 150 μM ATP, 0.25 mM sodium orthovanadate, 2 mM DTT) with or without ˜20 fold molar excess of ganglioside and 10 μCi [γ- 32 P]ATP. Then 10 μg of the Src kinase substrate peptide p34 cdc2 (6-20) (Upstate Biothechnology) was added to the mix and incubated at room temperature for the times indicated, after which the reaction was stopped by addition of 100 μM iodoacetamide and by precipitation of proteins with final 10% TCA. The supematant (containing the phosphorylated peptide substrate, not precipitated by TCA) was spotted on a P81 paper (Whatman) and washed three times with 0.75% phosphoric acid and once with acetone. The [ 32 P]-peptide content was quantified using a Storm 840 phosphorimager with ImageQuant software.
[0114] GD2 ligand design and synthesis: Peptides were modeled based on Tenascin-R sequence and on diversity within Tenascin family homologs. Peptides were synthesized with an Advanced Chemtech automatic synthesizer using solid-phase Fmoc chemistry. After cleavage from resin and side-chain deprotection, peptides containing terminal cysteines were subjected to cyclization by oxydation at 4° C. under O 2 in 50 mM ammonium bicarbonate, pH 8.5. Peptides were purified (>95%) by HPLC (Varian) using a C-18 preparative column (Phenomenex), and were verified by Mass Spectometry.
[0115] Assessment of peptide-GD2 interaction by competitive ELISA: ELISAs were as described above, except that peptides (50 μg/well, in PBS) were added to the wells for 1 hour before anti-GD2 mAb 3F8 or anti-GM1 cholera toxin-B. Selectivity of inhibition is controlled by lack of effect upon GM1-CTB interactions.
[0116] Intracellular calcium studies: cells (1×10 6 per sample) were washed with Ringer's solution (155 mM NaCl, 4.5 mM KCl, 2 mM CaCl 2 , 1 mM MgCl 2 , 10 mM D-glucose, 5 mM HEPES) and resuspended in 1 ml Ringer's containing 10 μM p56 Lck inhibitor PP1 (BioMol) or vehicle for 15 minutes at 37° C. Then 5 μM Rhod-2AM (Molecular Probes) was then added to the cells and incubated for 30 minutes at room temprature with mild agitation. Cells were washed once in Ringer's, resuspended in 1 ml Ringer's and incubated for 30 minutes, after which cells were stimulated with the indicated ganglioside ligands (or calcium ionophore A23187 as control) and analyzed over a 30 minute period for intracellular Ca 2+ using a flow cytometer (Becton-Dickinson).
[0117] Soft agar colony formation: single cell suspensions of EL4 GD2 negative and EL4 GD2 positive were plated (1500 cells/plate) with or without mAb 3F8 ( 50 μg/plate) in top layer medium (RPMI 1640 containing 0.35% agar, 15% fetal bovine serum, 2 mM glutamine, 10 mM Hepes and penicillin/streptomycin) on top of a preformed bottom layer (same as above except 0.5% agar) in 100 mm polystyrene dishes (Falcon) and grown until colonies are visible by eye. Colonies were counted in a predetermined area of the plates.
[0118] In vivo tumor studies: single cell suspensions of EL4 GD2 negative and EL4 GD2 positive in Hanks' balanced salt solution (Gibco) were injected intraperitonially in nude Balb/c mice (Charles River) (1×10 6 cells per animal). Animals were sacrificed and autopsied after 7 to 10 days, depending on tumor growth.
[0119] In vitro CD45 phosphatase assay: human recombinant CD45 enzyme (BioMol, 75 units/well) was preincubated in the absence (negative control) or presence of sodium orthovanadate (positive control) or various gangliosides (16.7 μM) for 20 minutes at room temperature in half-volume 96-well microtiter plates. A CD45-specific substrate (pp60 Src C-terminal phosphoregulatory peptide, 200 μM) was then added for 20 minutes at 30° C., afterwhich the reaction was stopped and quantified with BioMol Green reagent. Plates were read at 620 nm with a Biorad 550 platew reader.
[0120] Ex vivo CD45 assay: single cell suspensions of EL4 GD2 negative and EL4 GD2 positive (1×10 7 cells/ml per treatment) were incubated in the presence of 5 μg/ml of mlg (negative control), anti-GD2 antibody 3F8 or anti-CD3 antibody 145-2C11 (Pharmingen) cross-linked with anti-hamster G94-56 (Pharmingen) for 20 minutes at 37° C. in RPMI 1640 medium supplemented with 5% fetal bovine serum, 2 mM glutamine, 10 mM Hepes and penicillin/streptomycin. Cells were then washed and detergent lysed. p56 Lck was then immunoprecipitated with anti-p56 Lck antibody coated beads and probed for phosphotyrosine 505 by western blotting with anti-PY505 (Cell Signaling Technology).
[0000] Results
[0121] To study a specific physical association between p56 Lck and gangliosides, a panel of cells was generated varying in expression of cell surface GD2, GM1, GM2 and GD3, as assessed by flow cytometry. The indicated cells (Table 2) express similar levels of p56 Lck (data not shown).
TABLE 2 Surface ganglioside expression of cells studied as assessed by FACScan Ganglioside profile p56 Lck Cells Source GM1 GD2 GD3 GM2 expression EL4 GD2 positive lymphoma mouse C57/bI6n Low high negative negative High EL4 GD2 negative lymphoma mouse C57/bI6n Low negative medium negative High R1.1 lymphoma mouse C58/J High low negative negative High
Specific and Stable Association of p56 Lck -GD2.
[0122] We performed anti-GD2 immunoprecipitations with mAb 3F8 followed by western blotting with anti-p56 Lck antibodies ( FIG. 2A ). In EL4 GD2 positive cells p56 Lck was co-precipitated with mAb 3F8 but not with control mouse IgG. In control R1.1 cells, which are GD2 negative , no antibody co-precipitated p56 Lck , although p56 Lck is expressed at high levels.
[0123] The presence and kinase activity of p56 Lck in anti-GD2 immunoprecipitates were verified and quantified ( FIGS. 2B and 2C ). The indicated immunoprecipitations were done on EL4 GD2 positive or EL4 GD2 negative cells, followed by in vitro kinase assays using the specific p56 Lck substrate Sam68. In EL4 GD2 positive approximately 15% of the p56 Lck activity was co-precipitated by anti-GD2 mAb 3F8 ( FIG. 2B , lane 1), compared with anti-Lck mAb 3A5 ( FIG. 2B , lane 2). In fact, anti-GD2 co-precipitation of the p56 Lck activity was comparable to co-precipitation by antibodies against Zap70 ( FIG. 2B , lane 3). This was in keeping with the fact that Zap70 and p56 Lck are reportedly associated physically and functionally in vivo.
[0124] The specificity of these assays is validated in studies using EL4 GD2 negative cells, where anti-GD2 mAb 3F8 did not co-precipitate a p56 Lck activity ( FIG. 2B , lane 4), while anti-Lck and anti-Zap70 antibodies did ( FIG. 2B , lanes 5 and 6). Because p56 Lck co-immunoprecipitations with anti-Zap70 antibodies were comparable in EL4 GD2 positive and EL4 GD2 negative cell lines ( FIG. 2B , lanes 3 and 6), the data suggest that association of Zap70 and p56 Lck can be GD2 independent.
[0125] Similar studies were done using EL4 GD2 positive or R1.1 (GD2 negative ) cells and assaying a p56 Lck activity by in vitro kinase activity upon the selective substrate Gap62 ( FIG. 2C ). Again, anti-GD2 co-purified a p56 Lck activity that corresponds to ˜15% of the activity purified with anti-Lck mAb 3A5. In contrast, affinity isolation of GM1 with cholera toxin b subunit-coupled beads did not co-purify a p56 Lck activity ( FIG. 2C , lane 4), although R1.1 cells have high levels of GM1 and p56 Lck ( FIG. 2C , lane 3).
[0126] The converse experiment was performed where p56 Lck was first immunoprecipitated with mAb 3A5 and then the presence of GD2 or GM1 were gauged by ELISA ( FIG. 2D ). Anti-p56 Lck immunoprecipitates from EL4 GD2 positive cells contained ˜55% of the GD2 that could be isolated with anti-GD2 mAb 3F8. In specificity controls, anti-p56 Lck immunoprecipitates from R1.1 cells did not co-precipitate the ganglioside GM1.
[0000] Functional Relevance of p56 Lck -GD 2 Association in the Absence of GD2 Ligands.
[0127] Subsequent experiments ( FIG. 3 ) addressed in vitro whether there is a functional relevance to the stable and selective GD2-p56 Lck association. Addition of exogenous GD2 to purified p56 Lck increased the kinetics of in vitro enzymatic activity from a t 1/2 of ˜25 minutes to a t 1/2 of ˜17 minutes, with a dramatic 70% increase in kinase activity at 20 minutes. However, the v max did not change, as the enzyme activity reaches a similar plateau with or without GD2 present. In control assays, p56 Lck kinase activity was not altered upon addition of exogenous GM1 ( FIG. 3 ), or addition of phosphatidylcholine or other lipids (data not shown).
[0000] Development of Artificial GD2 Ligands.
[0128] Small peptides (6-13 amino acids in length) were designed to span the primary sequence of the GD2 ligand Tenascin-R. Cyclization and other conformational constrains were introduced in these peptides to conformationally constrain them and to forcethem to adopt the β-turn structures desired.
[0129] These peptides (˜100 were synthesized) were tested for inhibition of GD2-mAb 3F8 interactions in ELISA plates (Table 3). No competitor peptide added or control irrelevant peptide added were standardized as 100% binding. For simplicity, only some of the ˜90 inactive peptides are shown.
[0130] In various embodiments, peptide analogs that actively inhibit GD2-mAb 3F8 interactions span the sequence NH 2 -Ile-Thr(Ala)-Asn-Tyr-Asn-COOH. In some embodiments, peptides of the invention may be in type IV (3:5 or 3:3) canonical β-turn configurations with a distance between the Cα1 to Cα4 atom varying between 4 and 7 Å, depending on whether Gly residues (underlined) are incorporated in the sequence. Additionally, a linear peptide of 11 amino acids (pep 51), which is unstructured in solution (data not shown) can also act as a competitive inhibitor.
TABLE 3 Selected peptide mimics . . . % Inhibition of mAb 3F8-GD2 Peptides Sequence Conformation interactions Pep 51 G G I T N Y N S A L M linear 44.96 ± 1.57 Pep 52 C G G I T N Y N S A C cyclic 30.17 ± 2.69 Pep 53 C I T N Y N S C cyclic 24.74 ± 3.29 Pep 54 C G G I T N Y N C cyclic 40.34 ± 3.17 Pep 55 C T N Y G V H C cyclic 12.23 ± 4.41 Pep 56 C T N Y G V C cyclic 14.13 ± 5.43 Pep 57 G G I A N Y N T S linear 4.33 ± 5.23 Pep 58 C G G I A N Y N C cyclic 47.60 ± 4.26 Pep 59 C G G I A N Y N T S C cyclic 48.83 ± 5.01 Pep 60 C I A N Y N T C cyclic 30.94 ± 3.53
[0131] Inhibition of mAb 3F8 bindng to immobilized GD2 by peptides, measured by competitive ELISA. No peptide or control peptide treatments are standardized as 0% inhibition. No mAb 3F8 treatment is standardized as 100% inhibition. Average of 5 indepedant experiments, n=4 in each experiment. Mean±SEM.
[0000] Functional Relevance of GD2 Ligands in p56 Lck Activation.
[0132] This example illustrates (i) whether engagement of cell surface GD2 with ligands causes the pTyr of p56 Lck ( FIG. 4A ); (ii) whether engagement of cell surface GD2 with ligands leads to the pTyr of the downstream effector Zap70 ( FIG. 4B ); (iii) whether engagement of cell surface GD2 induces intracellular calcium fluxes ( FIG. 4C ).
[0133] First, engagement of cell surface GD2 in living EL4 GD2 positive cells with the artificial GD2 ligand mAb 3F8 caused the pTyr of p56 Lck within 5 min in vivo ( FIG. 4A , lanes 3 and 4). Control mouse IgG did not cause this effect ( FIG. 4A , lanes 1 and 2).
[0134] Second, since the pTyr of p56 Lck can lead either to activation or to inactivation of this kinase depending on which Tyr residue gets phosphorylated, the pTyr profile of Zap70 was studied in vivo because it is an adapter molecule downstream of and phosphorylated by activated p56 Lck . Zap70 is transiently pTyr upon engagement of cell-surface GD2 with mAb 3F8 as a ligand ( FIG. 4B , lanes 3 and 4). This Zap70 pTyr presumably occurs via p56 Lck . Control mouse IgG did not cause Zap70 pTyr in EL4 GD2 positive cells ( FIG. 4B , lanes 1 and 2). In other specificity controls, treatment of EL4 GD2 negative cells with GD2 ligands did not cause pTyr of p56 Lck or Zap70 (data not shown) indicating that cell surface GD2 expression may be required for ligand engagement of GD2 and a subsequent effect downstream, in some embodiments.
[0135] Third, intracellular Ca ++ concentrations were measured in live EL4 GD2 positive cells after engagement of cell-surface GD2 with ligands ( FIG. 4C ). Flow cytometric analysis using the Ca ++ sensitive Rhod-2 fluorophore showed a rapid (˜5 minutes) 1.6 fold increase of intracellular Ca ++ after mAb 3F8 binding, but not after binding by control mouse antibody or CTB (data not shown). The selective p56 Lck kinase inhibitor PP1 (10 μM) markedly decreased mAb 3F8-induction of Ca ++ fluxes. This control suggests that activated p56 Lck may be responsible for aspects of the GD2 signal transduction pathway leading to intracellular Ca ++ fluxes in some embodiments.
[0000] Functional Relevance of the Presence of GD2 on CD45 Activity.
[0136] Since the CD45 phosphatase is responsible for the activation of p56 Lck , the effect of GD2 on CD45 activity was investigated. First, the effect of GD2 was tested in vitro using human recombinant CD45 enzyme and pp60 Src phosphoregulatory peptide as a substrate. As seen in FIG. 5 , GD2 can drastically inhibit CD45 phosphatase activity (85% inhibition), while other gangliosides (GM1, GM2, GD3 and GM3) had little influence on the enzymatic activity of CD45. Other than GD2, only GD1a showed significant inhibition (50%).
[0137] The inhibitory effect of GD2 on CD45 is also seen in live cells, as shown in FIG. 6 . Here, EL4 GD2 positive and EL4 GD2 negative cells were stimulated using the well-documented T cell receptor cross-linking methodology, which typically results in activation of p56 Lck following its dephosphorylation at tyrosine 505 by CD45. Interestingly, EL4GD2 positive cells are resistant to activation ( FIG. 6 , lane 3), while the EL4 GD2 negative cells ( FIG. 7 , lane 6) are readily activated upon T cell receptor cross-linking. This discrepancy can be attributed to the presence of GD2 in EL4 GD2 positive cells which can block CD45-mediated activation of p56 Lck . Of interest is the fact that GD2 ligands, such as mAb 3F8, seem to be able to alleviate GD2 inhibition of CD45 and allow for T cell receptor activation as seen by dephosphorylation of tyrosine 505 on p56 Lck ( FIG. 6 , lane 2).
[0000] Functional Relevance of GD2 and GD2 Ligands in Tumorigenic Growth.
[0138] To illustrate the effect of cell surface expression of GD2 on cancer cell growth and survival, EL4 GD2 positive and EL4 GD2 negative cells were grown in clonoenic (soft agar) assays ( FIG. 7 ), or they were injected in vivo intraperitoneally ( FIG. 8 ).
[0139] Colony formation assays in soft agar showed marked differences in growth dynamics for EL4 GD2 positive and EL4 GD2 negative cells. At day 10 of growth, the total number of EL4 GD2 positive colonies per plate were lower by 50% compared to EL4 GD2 negative colonies ( FIG. 7 a ). Moreover the EL4 GD2 negative colonies were much larger and contained more cells ( FIG. 7 b ). This is striking because both cell lines have identical doubling times in liquid culture.
[0140] Addition of mAb 3F8 in the agar layer (where it putatively diffuses, engages and activates GD2-mediated signals) totally abolished EL4 GD2 positive colony formation while having no consequences on the number and size of EL4 GD2 negative colonies. This illustrates that the GD2 ligands of the invention may be used to treat GD2 positive cells to modulate growth, for example to treat cancer cells expressing GD2 to inhibit the growth of such cells or to kill the cells. In some embodiments, EL4 GD2 positive cells die by apoptosis when GD2 is bound (data not shown), indicating that the presence of GD2 may in some embodiments allow the GD2 ligands of the invention to be used to induce apoptosis.
[0141] An evident difference is also observed when cells are grown in vivo. When injected intraperitoneally EL4 GD2 negative cells mainly form aggressive and metastatic ascitic tumors and the peritoneal cavity contains mucin-like peptidoglycans. In contrast, EL4 GD2 positive cells form localized, highly vascularized solid tumors attached to the peritoneal membrane ( FIG. 8 ).
[0000] Conclusion
[0142] Although various embodiments of the invention are disclosed herein, many adaptations and modifications may be made within the scope of the invention in accordance with the common general knowledge of those skilled in this art. Such modifications include the substitution of known equivalents for any aspect of the invention in order to achieve the same result in substantially the same way. Numeric ranges are inclusive of the numbers defining the range. In the specification, the word “comprising” is used as an open-ended term, substantially equivalent to the phrase “including, but not limited to”, and the word “comprises” has a corresponding meaning. Citation of references herein shall not be construed as an admission that such references are prior art to the present invention. All publications, including but not limited to patents and patent applications, cited in this specification are incorporated herein by reference as if each individual publication were specifically and individually indicated to be incorporated by reference herein and as though fully set forth herein. The invention includes all embodiments and variations substantially as hereinbefore described and with reference to the examples and drawings.
REFERENCES
[0143] The following documents are hereby incorporated by reference:
Cheung, N. K., Saarinen, U. M., Neely, J. E., Landmeier, B., Donovan, D., and Coccia, P. F. (1985). Monoclonal antibodies to a glycolipid antigen on human neuroblastoma cells, Cancer Research 45, 2642-9. Eisenberg, D., Schwarz, E., Komaromy, M., Wall, R. (1984). Analysis of membrane and surface protein sequences with the hydrophobic moment plot, Journal of Molecular Biology 179, 125-42. Gagnon, M., and Saragovi, H. U. (2002). Gangliosides: therapeutic agents or therapeutic targets?, Expert Opinion on Therapeutic Patents 12, 1215-1224. Probstmeier, R., Michels, M., Franz, T., Chan, B. M., and Pesheva, P. (1999). Tenascin-R interferes with integrin-dependent oligodendrocyte precursor cell adhesion by a ganglioside-mediated signalling mechanism, European Journal of Neuroscience 11, 2474-88. Saragovi, H. U., Greene, M. I., Chrusciel, R. A., and Kahn, M. (1992). Loops and secondary structure mimetics: development and applications in basic science and rational drug design, Bio/Technology 10, 773-8. Sorkin, L. S. (2000). Antibody activation and immune reactions: potential linkage to pain and neuropathy, Pain Medicine 1, 296-302. | The invention provides ligands of ganglioside GD2, including peptide ligands such as GGITNYNSALM; YCGGITNYNSACY; YCITNYNSCY; YCGGITNYNCY; YCTNYGVHCY; YCTNYGVCY; GGIANYNTS; YCGGIANYNCY; YCGGIANYNTSCY; and, YCIANYNTCY. GD2 ligands of the invention may for example be used to treat or diagnose diseases such as cancers in which cells express GD2, including neuroblastomas. | 2 |
[0001] This is a continuation of patent application Ser. No. 09/697,665, filed on Oct. 25, 2000. That application is incorporated in its entirety by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to screening equipment such is used in connection with water treatment plants and wastewater treatment facilities. The general purpose of such screening equipment is to remove solids from the fluid stream so that the solids may be processed separately from the fluid stream.
DESCRIPTION OF RELATED ART
[0003] A typical water or waste water treatment plant includes some means to screen solids from the fluid flowing into a treatment facility; this is often the first stage of treatment. For example, it is often important to catch and remove rocks, paper, cotton, cloth, or other debris from a fluid stream to protect downstream processing equipment. For another example, solids may be separated from a diversion water stream (CSO screening), wherein the solids are returned to the stream for subsequent treatment, allowing the excess liquid of a storm to by-pass sewage treatment works or to flow to storage for subsequent treatment.
[0004] Certain types of solids cause particular problems for fluid screening equipment. In particular, the widespread use of non-soluble, not readily biodegradable plastic tampon applicators is now causing significant visual and physical problems in conventional sewage treatment plants. The screening mechanisms widely used in the later half of the twentieth century were not intended for removing ½″ inch diameter and smaller solids, and consequently these solids are now reporting in filters, digesters, and even in plant discharges to receiving streams, lakes, and oceans. Depending on the type of equipment used, this causes obvious problems for the operation of the screening equipment, environmental problems, or both.
[0005] Rocks and gravel sometimes cause extreme difficulties for bar screens and screenings compactors. There is a present need for a device to remove these materials prior to screening.
[0006] A number of machines have been developed in recent years for the general purpose of removing solids from a fluid stream. Representative machines are disclosed in U.S. Pat. Nos. 4,188,294; 3,856,678; and 3,615,022 of Hagihara (plastic element filter screens); U.S. Pat. No. 1,207,376 of Davidson; U.S. Pat. No. 4,812,231 of Wiesemann (metal element screen); Link Belt traveling water screens of about 1956 or 57; and U.S. Pat. No. 2,929,504 of Lind et al. (screw screens).
[0007] Each of the above designs has certain inherent weaknesses which causes the design to be sub-optimal. For example, the plastic filter element of Hagihara has a high mortality rate and is difficult and time consuming to replace; and the filter screens derived from Wiesemann are reportedly high maintenance. Both types of screens require either pivotable or removable mountings to remove the screenings that become trapped between the down-going and up-going sections of the filtering chain conveyer. For another example, traveling water screens have tray cleaning problems associated with the fine openings of the trays, and also have sealing problems at the moving joints. For yet another example, screw screen designs impose severe lay-out constraints. Finally, the rack of spaced parallel bars that are cleaned by a rake are problematic when used with very small openings because the relatively narrow cleaning teeth, which must be narrower then the bar spacings, are weak and readily damaged.
[0008] The above efforts in the development of screening devices, and the problems that have not been solved, show that a simple, reliable, and economical screening mechanism would be a welcome advance in the art.
SUMMARY
[0009] The present invention is a device and method for clearing debris from fluid channels. In one embodiment, the device is a screening member that is permeable in part wherein debris will collect. A movable scraper then scrapes along the screen and removes the debris therefrom and transports the debris to a desired location. An embodiment of the invention, the surface that comprises the screen member, may be arcuate, and may be a surface of revolution. Different portions of the screening number may or may not be permeable. The invention may also include an overflow mechanism where overflow water is diverted into a separate unscreened fluid stream. Further, the invention may be suitable for use within a sump.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] [0010]FIG. 1 is a side elevation view of an embodiment of the present invention, shown in a typical operating environment.
[0011] [0011]FIG. 2 is plan view of an embodiment of the present invention, taken along the section C-C of FIG. 1.
[0012] [0012]FIG. 3 is an upstream elevation view of an embodiment of the invention, taken along the section A-A of FIG. 1.
[0013] [0013]FIG. 4 is a downstream elevation view of an embodiment of the invention, taken along the section B-B of FIG. 1.
[0014] [0014]FIG. 5 is a plan view of another embodiment of the invention, illustrating use in a storm overflow design.
[0015] [0015]FIG. 6 is a side elevation view of another embodiment of the present invention, shown recessed in a sump in an operating environment.
DETAILED DESCRIPTION
[0016] A device according to an embodiment of the present invention is shown in side elevation in FIG. 1. The device is situated in a fluid stream F constrained within a channel (the channel is bounded by boundary C such as concrete defining the channel as shown in FIG. 2). The fluid stream F has a flow direction as indicated by the flow arrow. The device includes a moveable pair of chains 1 (further described as 1 a and 1 b ) that revolve around the perimeter of the fluid stream F, from a point substantially near the bottom of the fluid stream F to a point above a top level L of the fluid stream. It will be understood that the chains 1 are simply representative of a moving means and could be replaced by a single chain, a belt, or any other moving member which is capable of moving within and above the fluid stream F.
[0017] The chains 1 are retained by chain guides 6 (see FIG. 2). In more detail, the chains 1 comprise front chain 1 a and rear chain 1 b (see FIG. 1), which are respectively retained by front chain guides 6 a and rear chain guides 6 b . The chain guides 6 can be any means capable of constraining the movement of the chains along their desired path, while still allowing the chains 1 to move as intended. Of course, if the chains 1 were replaced by a single chain, a belt, or other moving member, the chain guides 6 would be replaced with another suitable guiding components. As used above, “front” corresponds to upstream and “rear” corresponds to “downstream.”
[0018] One or more scrapers 2 are attached to chains 1 and move along with the movement of chains 1 . The scrapers may be a rigid scraper blade, brush, bucket, or any other component suitable for attachment to chains 1 and for engaging and moving solid debris. As shown in FIG. 1, two scrapers 2 are attached to the chains 1 but it will be understood that more or fewer may be used. As explained more below, the purpose of the scrapers are to engage and move solids from the fluid stream F to another location.
[0019] The device includes a fixed media filter screen 5 . By fixed, it is meant that the screen 5 is stationary in the fluid stream F once it has been installed. The screen 5 is permeable, and, for example, may be made of wedge wire screen, perforated metallic or non-metallic sheet, or woven membrane. The screen 5 has clear spacings of a certain preselected size designed to filter out debris of a certain size. The perforations have a cross sectional area that may be circular, rectangular, slotted, or otherwise shaped. The perforations have a cross section that has a maximum length and width that may be equal (such as a circle or square) or may vary by some multiple such as by a factor of, for example, fifteen, in the case of slotted perforations. The number fifteen is only exemplary and not a maximum. As used herein, a perforated screen is distinguishable from a bar screen, which has spacing that are vastly longer in one direction (parallel to the bars) than in the other (perpendicular to the bars). The screen may have a number of different shapes, but in an example and presently preferred embodiment the screen 5 is generally U shaped with the bottom portion of the U being adjacent the bottom of the fluid stream F and the extending sides of the U extending upward along the sides of the fluid stream F. The extending portion of one of the sides of the screen 5 is shown in the view of FIG. 1, and the bottom of the screen 5 is shown in the plan view of FIG. 2. The precise height of the screen 5 is not critical, but the height of the screen is preferably above the expected maximum height (L) of the fluid stream F, as is shown in FIG. 1.
[0020] As alternative embodiments, screen 5 could be other than U shaped. For example, the permeable surface could be any section of a surface of revolution. Or, the permeable surface could be a planar extension of a lower surface of revolution. As well as being capable of being constructed of numerous shapes, the screen 5 is not limited to any particular arrangements of permeable surface and non-permeable surface. While the primary purpose of the screen 5 is to serve as a screening element, that purpose can be achieved with a number of different screen shapes.
[0021] An upstream view looking into the device is shown in FIG. 3. A front plate 12 generally encloses a major portion of the screening mechanism. The size and shape of the front plate 12 is designed to correspond to the dimension of the fluid stream F at the location that the fluid stream F contacts the plate 12 . The plate 12 has an aperture 7 to admit fluid from fluid stream F into proximity with the screen 5 . The exact size and shape of the aperture 7 is not critical, but the size and shape of the aperture 7 is such that the admitted fluid will be into the interior of the screen 5 . Stated another way, the admitted fluid will be at least partially bounded by the bottom and sides of U shaped screen 5 .
[0022] A downstream view looking into the device is shown in FIG. 4. A fluid impermeable rear plate 13 generally comprises the rear of the device, primarily blocking the fluid stream F. The rear plate 13 has an aperture 8 , however in normal intended operation the aperture 8 is above the expected fluid flow level L so that fluid will not pass through the aperture 8 . Instead, the aperture 8 is positioned above level L, and serves as a heavy flow bypass, as described in more detail below.
[0023] It will now be appreciated that the front plate 12 , rear plate 13 , and screen 5 define a volume into which the flow F is directed. Since the front and rear plates are fluid impermeable, the fluid flow F is directed through the screen 5 . The screen 5 thus serves as a filter for the fluid flow F, and filters out solids that have a cross section greater than the size of the clear spacings in the screen 5 .
[0024] The filtered solids are removed from the screen 5 by the scrapers 2 . As shown in FIGS. 1 and 3, the chains 1 and scrapers 2 are located with respect to the screen 5 so that as the chains 1 move, the scrapers 2 will scrape along the interior of the screen 5 and will engage and carry the filtered solids. The scrapers 2 move in a path having a high point and a low point The movement of the scrapers is arcuate in the vicinity of the high point and low point and is substantially vertical between the vicinity of the high point and the low point. In the exemplary embodiment, the arcuate path is caused by sprockets 3 at the high point and similar sprocket at the low point. In between the sprocket, the movement is vertical. This arrangement allows for embodiments of the invention to be easily used in relatively deep channels or channels having deep flows, which would be substantially more difficult with prior art devices such as drum conveyers.
[0025] In the illustrated embodiment, the scrapers 2 discharge into a conveyer 10 that removes and conveys the filtered solids from the scrapers 2 to a desired location. As the conveyer 10 can include any of a number of type of devices such as wiper blades that are intended to remove and transport solids from a scraper, it need not be described in detail and is shown schematically. Examples of cleaning implements to clean the scrapers 2 include without limitation any blade or blades, brush or brushes, or the force of spraying water or other liquids or gases. The conveyer 10 can convey the filtered solids to any convenient point of disposal such as via a discharge chute or a compactor.
[0026] The chains 1 of the illustrated embodiment are supported by sprockets 3 , the sprockets being further designated as 3 a and 3 b . In particular, chain 1 a is supported by sprocket 3 a and chain 1 b is supported by sprocket 3 b , both of which are attached to rotating shaft 3 c , which is supported by adjustable bearings 3 d . The rotating shaft 3 c is rotated by a motorized device 4 , which is conventional. It will be appreciated that sprockets 3 and related drive components are merely one means of moving the chains 1 , and the present invention includes any other means to move the chains 1 . It will further be appreciated that if alternatives to the chains 1 are used such as a single chain or a belt, corresponding drive means may be included instead of or in addition to the above described drive system. Moving one or more chains or belts generally as described in connection with the present invention is well understood and the present invention includes all drive means.
[0027] The fluid flow F directed through the screen 5 enters a relief channel R. As shown in FIG. 2, the relief channel is positioned below and to the sides of the screen 5 , so that fluid can drain through the bottom and the sides of the U shaped screen 5 . The fluid flow can then be redirected into a channel to form fluid stream F 2 . It will be understood that while relief channel as described above allows drainage through the sides and the bottom of the filter screen 5 , other embodiments of the invention could provide for drainage either only through the bottom or only through the sides of the screen 5 .
[0028] The heavy flow bypass feature is now described in more detail. The aperture 8 is adjustable by adding or subtracting one or more weir bars 9 that engage the rear plate 13 . Adding weir bars 9 raises the opening height of the aperture 8 , so that a greater fluid flow level L will be required to cause any portion of the fluid to flow through the aperture 8 . It may be desirable to adjust the aperture 8 depending upon the conditions of the treatment equipment being used with the device, or for other reasons. Other embodiments of the invention could provide for adjustability of the aperture 8 by other means, such as gate that can be raised or lowered.
[0029] Another aspect of the invention is described in connection with FIG. 5, which is a plan view comparable to FIG. 2. In the embodiment illustrated in FIG. 5, the fluid flow F is split into fluid flows F 1 and F 2 . Fluid flow F 1 is formed of the fluid that flows through screen 5 . This fluid flow will be screened of solids, and represents the “normal” discharge of the device. Fluid flow F 2 is formed of fluid that flows through aperture 8 . This fluid is not screened of solids, and represents fluid such as storm overflow that exceeds the normal operating volume of the device. The fluid flow F 2 could lead to a retention pond or other suitable overflow reservoir.
[0030] Another aspect of the invention is shown in FIG. 6. Components similar to those described above are denoted with a ′ for ease of reference. A fluid flow F′ such as that contained within a pipe or channel has a sump S which is a recessed space below the adjacent floor of the pipe or channel. Thus, heavy debris such as rocks or other heavy solids will tend to settle in the sump S. The sump S is cleaned by one or more scrapers 2 ′. The scrapers 2 ′ are reciprocated between the sump S and a higher elevation by chains 1 ′, which are turn driven by motor M driven sprockets 3 ′.
[0031] It will be clear that the while a presently preferred embodiment has been described, other embodiments may also be used that will still fall within the scope of the claims. Preferably, the axis of a device according to the invention is aligned parallel to the flow line vector (as shown in the figures), the invention also contemplates other alignments. Further a number of such devices may be used together in order to provide sufficient hydraulic capacity. | The present invention is a device and method for clearing debris from fluid channels. In one embodiment, the device has a fixed screening member that is permeable in part wherein debris will collect. A movable scraper then scrapes along the screen and removes the debris therefrom and transports the debris to a desired location. In embodiments of the invention, the surface that comprises the screening member may be arcuate, and may be a surface of revolution. Different portions of the screening member may or may not be permeable. The invention may also include an overflow mechanism where overflow water is diverted into a separate unscreened fluid stream. Further, the invention may be suitable for use within a sump. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a latch for releasably securing a first member, such as a door, panel or the like, relative to a second member.
2. Description of the Prior Art
Latches are used to releasably secure panels, covers, doors, electronic modules, and the like to other structures such as compartments, cabinets, containers, doorframes, other panels, frames, racks, etc. Although many latch designs are known in the art, none offers the advantages of the present invention. The advantages of the present invention will be apparent from the attached detailed description and drawings.
SUMMARY OF THE INVENTION
The present invention is directed to improvements in latch design. The illustrated embodiment of the present invention is a rotary pawl latch with the capability to provide a compressive force between the first member and the second member. The illustrated embodiment of the present invention is of an electromechanical type. The control circuit of the latch detects when a striker attached to one member, for example a door, has moved the pawl to a first latched position. A motor is then activated that drives the pawl to a second latched position to provide compression between the first member and a second member, for example a door frame.
It is an object of the present invention to provide an electromechanical latch that provides compression between two members.
It is another object of the present invention to provide an electromechanical latch that can reverse operation to open.
It is yet another object of the present invention to provide an electromechanical latch that can detect obstructions and reverse operation.
It is yet another object of the present invention to provide an electromechanical latch that can detect premature movement of the pawl to a fully latched position and reverse operation.
It is yet another object of the present invention to provide an electromechanical latch that continues to provide a latching function in the event of power failure.
It is yet another object of the present invention to provide an electromechanical latch that permits manual opening in the event of power failure.
These and other objects of the invention will become apparent from the attached description, drawings, and claims.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1-10 are views of a latch assembly according to the present invention.
FIGS. 11A-12 are exploded views of a latch according to the present invention.
FIGS. 13-15 are views of a latch according to the present invention showing the latch in the unlatched configuration with the cover removed to reveal internal detail.
FIG. 16 is a view of a latch according to the present invention showing the latch in the unlatched configuration.
FIGS. 17-21 are a sequence of views of a latch according to the present invention showing the pawl moving from the unlatched position to the first latched position with the cover removed to reveal internal detail.
FIG. 22 is a view of a latch according to the present invention showing the pawl in the first latched position.
FIGS. 23-25 are fragmentary views of a latch according to the present invention showing the pawl in the first latched position with the cover removed to reveal internal detail.
FIGS. 26-35 are a sequence of views of a latch according to the present invention showing the pawl moving from the first latched position to the second latched position and the cam gear returning to its starting position with the cover removed to reveal internal detail.
FIGS. 36-49 are a sequence of views of a latch according to the present invention showing the pawl moving from the second latched position to the unlatched position and the cam gear returning to its starting position with the cover removed to reveal internal detail.
FIGS. 50-51 are views of the second portion of the housing of a latch according to the present invention.
FIGS. 52-53 are views of the cam gear axle of a latch according to the present invention.
FIGS. 54-60 are views of the cam gear of a latch according to the present invention.
FIGS. 61-65 are views of the trigger spring of a latch according to the present invention.
FIGS. 66-68 are views of the trigger of a latch according to the present invention.
FIGS. 69-73 are views of the combination gear of a latch according to the present invention.
FIG. 74 is a view of the motor of a latch according to the present invention.
FIGS. 75-76 are views of the bushing for supporting the end of the motor shaft of a latch according to the present invention.
FIG. 77 is a view of the motor cover of a latch according to the present invention.
FIGS. 78-79 are views of the pawl axle of a latch according to the present invention.
FIGS. 80-83 are views of the pawl torsion spring of a latch according to the present invention.
FIGS. 84-86 are views of the pawl of a latch according to the present invention.
FIGS. 87-88 are views of the circuit board of a latch according to the present invention.
FIGS. 89-92 are views of the support plate of a latch according to the present invention.
FIGS. 93-94 are views of the torsion spring of the trigger actuator lever of a latch according to the present invention.
FIGS. 95-97 are views of the trigger actuator lever of a latch according to the present invention.
FIGS. 98-99 are views of the torsion spring of the striker detector of a latch according to the present invention.
FIGS. 100-104 are views of the striker detector of a latch according to the present invention.
FIGS. 105-106 are views of the first portion of the housing of a latch according to the present invention.
FIGS. 107-108 are views of the trigger axle of a latch according to the present invention.
FIGS. 109-110 are views of the combination gear axle of a latch according to the present invention.
FIGS. 111-112 are views of the worm gear of a latch according to the present invention.
The same reference numbers are used consistently throughout the several views.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIGS. 1-112 , a latch 200 in accordance with an exemplary embodiment of the present invention can be seen. The latch 200 includes a latch housing 202 , a pawl 204 , a trigger or catch 206 , and actuation means for selectively moving the trigger 206 out of engagement with the pawl 204 and for moving the pawl 204 from a first or initial latched position to a second or final latched position to thereby draw a portion of a striker farther into the interior of the housing 202 . In the illustrated embodiment, an electrically operated actuator assembly 208 serves as the actuation means.
The latch 200 is generally applicable wherever one or more closure members need to be secured in a certain position. The latch 200 can be used together with the striker 308 to secure any two closure members together. In the illustrated example, the latch 200 is shown being used for securing a panel 300 relative to some compartment (not shown) for which the panel 300 serves as a closure. In use, the latch 200 can be secured to the interior of the compartment, for example the passenger compartment of an automobile, using any well known means such as, for example, screws, bolts, or the like, with the latch 200 positioned such that it can be engaged by the striker 308 .
Preferably, the housing 202 is of the two-piece type having a first portion 211 and a second portion 213 so as to allow the housing 202 to receive the various components of the latch 200 . Furthermore, the housing must be adapted to allow an unobstructed path to the pawl slot 258 for the striker 308 when the pawl 204 is in the open or unlatched position relative to the housing 202 . The housing 202 has an opening that allows at least a portion of the striker 308 to enter the housing 202 for engagement by the pawl 204 . In the illustrated example, the opening is in the form of a slot 212 that passes through the first and second portions 211 , 213 of the housing 202 . The slot 212 forms an open, approximately U-shaped cut-out in the housing 202 as viewed in profile. The slot 212 allows at least a portion of the striker 308 to enter the housing 202 for engagement by the pawl 204 . The slot 212 allows an unobstructed path to the pawl slot 258 when the pawl 204 is in the open configuration relative to the housing 202 . The slot 212 is sized such that the housing 202 will not interfere with the movement of the striker 308 relative to the housing 202 as the pawl 204 is moved from the unlatched position to the first latched position relative to the housing 202 by contact with the striker 308 and as the pawl 204 is rotated to the second latched position relative to the housing 202 by the electrically operated actuator assembly 208 . In the illustrated example, the housing is provided with a motor cover 228 , which provides a protective cover for the motor.
The electrically operated actuator assembly 208 includes a motor 210 , a worm gear 214 that is in the form of an Archimedes or helical screw, a combination gear 216 , a cam gear 218 , the support plate 215 , and the printed circuit board 230 . The motor 210 has an output shaft 220 that normally rotates in response to the motor being energized. Reversing the polarity of the current supplied to the motor 210 causes the direction of rotation of the output shaft 220 to be reversed. The motor 210 is received in the housing 202 and is installed at a fixed location therein. The worm gear 214 is attached to the output shaft 220 of the motor 210 such that the worm gear 214 rotates with the shaft 220 as a unit during normal operation of the latch 200 .
The combination gear 216 includes two adjacent coaxial gear wheels 229 , 227 that rotate as a unit about a common axis of rotation. The first gear wheel 229 is of a larger diameter as compared to the second gear wheel 227 . The combination gear 216 , including the gear wheels 229 , 227 , may be of one-piece or two-piece construction. The combination gear 216 is rotationally supported in the housing 202 by the combination gear axle 223 . The worm gear 214 is in mesh with the combination gear 216 . In the illustrated example, the helical screw of the worm gear 214 engages the gear teeth 225 of the gear wheel 229 , such that the worm gear 214 is in mesh with a first set of teeth 225 of the combination gear 216 . Accordingly, rotation of the worm gear 214 causes rotation of the combination gear 216 when the motor 210 is energized.
The cam gear 218 includes a gear wheel 222 , a first cam 203 , and a second cam 205 . The first cam 203 is provided on one side of the gear wheel 222 and the second cam 205 is provided on the opposite side of the gear wheel 222 . The gear wheel 222 , the first cam 203 , and the second cam 205 rotate as a unit about a common axis of rotation. The gear wheel 222 of the cam gear 218 has a plurality of gear teeth 310 evenly distributed about its circumference. The first cam 203 has a cam lobe 207 , located at a distance from the axis of rotation of the cam gear 218 , for rotating the pawl 204 . The second cam 205 is in the form of an elongated, arc-shaped raised rib and functions to selectively trip or move the catch or trigger 206 . In the illustrated example, the cam gear 218 , including the gear wheel 222 , the first cam 203 , and the second cam 205 , is of one-piece construction. The cam gear 218 is rotationally supported in the housing 202 by the cam gear axle 209 . The cam gear 218 is in mesh with the combination gear 216 . In the illustrated example, the teeth 310 of gear wheel 222 of the cam gear 218 engage the gear teeth 312 of the gear wheel 227 , such that the cam gear 218 is in mesh with a second portion or second set of teeth of the combination gear 216 . Accordingly, rotation of the combination gear 216 causes rotation of the cam gear 218 when the motor 210 is energized.
The support plate 215 is supported by the housing 202 in a fixed position relative to the housing 202 . The pawl 204 is supported for rotational movement relative to the support plate 215 and the housing 202 by the pawl axle 238 . The trigger 206 is supported for rotational movement relative to the support plate 215 and the housing 202 by the trigger axle 270 . The support plate 215 has a cut-out 224 proximate the pawl 204 such that the support plate 215 will not interfere with the movement of the striker 308 relative to the housing 202 as the pawl 204 is moved from the unlatched position to the first latched position relative to the housing 202 by contact with the striker 308 and as the pawl 204 is rotated to the second latched position relative to the housing 202 by the electrically operated actuator assembly 208 . The support plate 215 has a first window in the form of an arcuate, elongated slot 221 that allows the position of the pawl to be detected by sensors 332 and 316 provided on the circuit board 230 . The printed circuit board 230 is positioned on the opposite side of the support plate 215 as compared to the pawl 204 , the trigger 206 and the cam gear 218 . The circuit board 230 is supported by the housing 202 in a fixed position relative to the housing 202 and the support plate 215 .
The support plate 215 has a second window 324 to allow detection of the position of the cam gear 218 by a sensor 326 provided on the circuit board 230 . The second window 324 is square shaped. A portion of the cam lobe 207 of the first cam 203 registers with the second window 324 , at least when the cam gear 218 is in its initial or starting position, to allow the sensor 326 to detect when the cam gear 218 is in its initial or starting position. The sensor 326 then generates a signal to the latch control circuit 235 when the cam gear 218 is in its initial or starting position to thus allow the latch control circuit 235 to detect whether or not the cam gear 218 is in its initial or starting position.
As previously stated the latch assembly 200 includes a pawl 204 shown pivotally or rotationally supported on the support plate 215 with suitable attachment means such as the pawl axle 238 that passes through the hole 240 in the pawl 204 . The support plate 215 is provided with a hole 232 for receiving part of the pawl axle 238 . Thus, the pawl 204 is rotationally supported relative to the support plate 215 .
The pawl 204 has first and second notches 254 , 233 provided for engagement by the trigger 206 . The pawl 204 is provided with a pawl slot 258 to capture and hold the striker 308 when the pawl 204 is in either one of the first latched position (shown in FIGS. 19-26 ) and the second latched position (shown in FIGS. 29-37 ) relative to the support plate 215 . In the illustrated example, the striker 308 has a rod-shaped portion 234 that engages the pawl slot 258 as the panel 300 , for example a car door, is moved to the closed position relative to the vehicle's passenger compartment (not shown) and consequently relative to the latch 200 .
During normal operation, assuming the latch 200 is initially in the normal unlatched configuration shown in FIGS. 13-16 , when the panel 300 is closed, the rod-shaped portion 234 of the striker 308 will be positioned or caught in the pawl slot 258 with the pawl 204 being moved to the first latched position relative to the support plate 215 and housing 202 .
A pawl torsion spring 262 is installed on the support plate 215 with the coiled portion 264 of the torsion spring 262 surrounding the pawl axle 238 . An arm 268 of the torsion spring 262 engages the pawl 204 . The torsion spring 262 also has a second arm 272 that engages the support plate 215 or the housing 202 .
With the arm 272 of the torsion spring 262 in engagement with the support plate 215 or the housing 202 , the arm 268 of the torsion spring 262 exerts a force on the pawl 204 that biases the pawl 204 toward the open or unlatched position relative to the support plate 215 .
The trigger 206 is pivotally supported on the support plate 215 . The pivot axis of the trigger 206 , as defined by the trigger axle 270 , is parallel to the pivot axis or axis of rotation of the pawl 204 . Furthermore, the pivot axis of the trigger 206 , as defined by the trigger axle 270 , is spaced apart from the pivot axis or axis of rotation of the pawl 204 . The trigger 206 is pivotally movable between any one of a first engaged position (shown in FIGS. 19-26 ) and a second engaged position (shown in FIGS. 29-37 ) and a disengaged position (shown in FIGS. 17 , 18 , and 39 ) and is spring biased toward the first and second engaged positions. In the illustrated embodiment, the first and second engaged positions of the trigger 206 may be coincident, but they need not be so. A trigger spring 288 is provided for biasing the trigger 206 toward the first and second engaged positions. In other words, the trigger spring 288 biases the trigger 206 toward engagement with the pawl 204 . The trigger spring 288 is a torsion spring and has a coiled portion 274 , a first arm 276 , and a second arm 278 . The trigger spring 288 is installed on the support plate 215 with the coiled portion 274 of the torsion spring 288 surrounding the trigger axle 270 . The arm 276 of the torsion spring 288 engages the trigger 206 . The second arm 278 of the torsion spring 288 engages the support plate 215 or the housing 202 .
The trigger 206 has a lever arm 284 that extends on one side of the pivot axis of the trigger 206 as defined by the trigger axle 270 . The trigger axle 270 passes through a hole in the trigger 206 . The trigger 206 has a tooth 290 that engages the first notch 254 of the pawl 204 to hold or retain the pawl 204 in the first latched position relative to the support plate 215 . Also, the tooth 290 of the trigger 206 engages the second slot 233 of the pawl 204 to hold or retain the pawl 204 in the second latched position relative to the support plate 215 .
The trigger 206 has associated with it a trigger actuator lever 286 . The trigger actuator lever 286 is mounted within the housing 202 so that it can rotate about a common axis with the trigger 206 . The trigger actuator lever 286 has a one-way rotation stop 236 . The trigger actuator lever 286 is provided with a torsion spring 242 that biases the one-way rotation stop 236 into engagement with the trigger 206 . When the cam gear 218 starts from its initial starting position (see FIGS. 13-15 ) and rotates in the first or forward direction until the second cam 205 engages the trigger actuator lever 286 , continued rotation of the cam gear 18 in the first direction moves the one-way rotation stop 236 away from or out of engagement with the trigger 206 such that the trigger actuator lever 286 can rotate out of the way of the second cam 205 without affecting the engagement of the trigger 206 with the pawl 204 . This allows the second cam 205 to slide past the trigger actuator lever 286 without affecting the position of the trigger 206 , which must be positioned to engage the notches 254 and 233 as the cam lobe 207 of the first cam 203 moves the pawl from the first latched position to the second latched position as seen in FIGS. 26-30 .
During the opening operation of the latch 200 , the cam gear 218 starts from its initial starting position (see FIGS. 32-35 ) and rotates in the second or reverse direction until the second cam 205 engages the trigger actuator lever 286 . Continued rotation of the cam gear 18 in the second direction moves the one-way rotation stop 236 into engagement with the trigger 206 such that the trigger actuator lever 286 cannot rotate relative to the trigger 206 with the result that the second cam 205 pushes the trigger 206 out of engagement with the pawl 204 so as to release the pawl 204 for rotation to the unlatched position as illustrated in FIGS. 36-49 .
During the opening operation of the latch 200 , the cam gear 218 starts from its initial starting position (see FIGS. 32-33 ) and rotates in the second or reverse direction until the first cam 205 disengages the trigger from the pawl 204 to thus release the pawl 204 for rotation to the unlatched position. At this same time the cam lobe 207 of the first cam 203 can engage the elongated prong 314 of the pawl 204 to assist the pawl 204 toward the unlatched position if the progress of the pawl 204 under spring bias is impeded by, for example, a sticky door seal. The length of the second cam 205 is selected such that the trigger 206 is disengaged from the pawl 204 during opening before the first cam 203 can engage the pawl 204 and such that the trigger 206 will remain disengaged from the pawl 204 until the first notch 254 is beyond any possibility of engagement with the trigger 206 .
A striker detector 318 is pivotally supported within the housing 202 by the support plate 215 . The striker detector 318 is provided with a torsion spring 244 that biases the striker detector 318 into occupying a first position coincident with the position of the rod-shaped portion 234 of the striker 308 when the striker 308 is captured by the pawl 204 and the pawl 204 is in the second latched position. Accordingly, when the striker 308 is captured by the pawl 204 and the pawl 204 is in the second latched position, the striker detector 318 is pushed to a second position by the striker 308 . A portion of the striker detector 318 registers with a third window 246 provided in the support plate 215 , at least when the striker detector is in its second position, to allow a sensor 320 to detect when the striker detector 318 is in its second position, which corresponds to the striker 308 being captured by the pawl 204 and the pawl 204 being in the second latched position. The sensor 320 generates a signal to the latch control circuit 235 when the striker detector 318 is in its second position to thus allow the latch control circuit 235 to detect whether or not the striker 308 is in the proper position when the pawl 204 is in the second latched position. In the illustrated example, the third window 246 is in the form of an arcuate, elongated slot. The sensor 320 is provided on the circuit board 230 .
In the illustrated embodiment, the sensors 316 , 320 , 326 , and 332 are of the opto-electronic type. Each sensor 316 , 320 , 326 , and 332 includes a light emitter and a light detector. The pawl 204 is provided with a reflective surface at the end of the pin 219 , which is inserted into a hole in the pawl 204 . When the pawl 204 is in the first and second latched positions or any position therebetween, the reflective surface at the end of the pin 219 registers with the first window 221 . When the pawl 204 is in the first latched position, the reflective surface at the end of the pin 219 registers with the first sensor 332 to generate a signal to the latch control circuit 235 indicating that the pawl 204 is in the first latched position. When the pawl 204 is in the second latched position, the reflective surface at the end of the pin 219 registers with the second sensor 316 to generate a signal to the latch control circuit 235 indicating that the pawl 204 is in the second latched position.
The cam lobe 207 has a raised platform 348 that is provided with a reflective surface 350 . When the cam gear 218 is in the initial or starting position, the reflective surface 350 registers with the second window 324 . When the cam gear 218 is in the initial or starting position, the reflective surface 350 registers with the third sensor 326 to generate a signal to the latch control circuit 235 indicating that the cam gear 218 is in the initial or starting position.
The striker detector 318 has a raised platform 352 that is provided with a reflective surface 354 . When the striker detector 318 is in the second position, the reflective surface 354 registers with the third window 246 . When the striker detector 318 is in the second position, the reflective surface 354 registers with the fourth sensor 320 to generate a signal to the latch control circuit 235 indicating that the striker detector 318 is in the second position.
The reflective surfaces can be provided by bright or reflective paint or metallization on the corresponding surfaces. It is possible to use other sensors such as Hall effect sensors or microswitches in place of the opto-electronic sensors used in the illustrative embodiment. If Hall effect sensors are used the reflective surfaces would be replaced by magnets embedded in the corresponding parts. If microswitches are used, all three windows would have to be in the shape of elongated arc-shaped slots with pins attached to the corresponding parts passing through the support plate 215 to actuate the microswitches on the circuit board 230 .
In the illustrated embodiment, the end of the arm 268 of the pawl spring 262 is intended to be bent down into the opposite side of the same hole 356 in the pawl 204 that is occupied in part by the reflective pin 219 . Alternatively, the pin 219 can be made long enough to project out of the opposite end of the hole 356 in the pawl 204 for engagement by the arm 268 of the pawl spring 262 .
The operation of the latch 200 will now be explained. With the latch initially in the fully unlatched configuration of FIGS. 13-16 , as the panel 300 is moved to the closed position, the rod-shaped portion 234 of the striker 308 will be positioned or caught in the pawl slot 258 with the pawl 204 being moved to the first latched position relative to the support plate 215 as a result of the contact of the striker 308 with the pawl 204 . The pawl 204 is now in the first latched position relative to the support plate 215 as illustrated in FIGS. 21-26 . The trigger 206 is in its first engaged position relative to the support plate 215 and retains the pawl 204 in its first latched position. The cam lobe 207 of the cam gear 218 is in its initial position shown in FIGS. 23-24 where it does not contact the pawl 204 . As shown in FIG. 23 , when the pawl 204 reaches the first latched position a pin 219 carried by the pawl communicates the position of the pawl 204 through the arc-shaped slot 221 in the support plate 215 to the sensor 332 that is mounted on the circuit board 230 on the side of the support plate 215 opposite the pawl 204 . Once the sensor 332 detects that the pawl 204 is in the first latched position, a signal is generated to an electronic latch control circuit 235 (shown diagrammatically), that may be located remotely or provided on the circuit board 230 , that controls the current supplied to the motor 210 , and in response the control circuit 235 causes the supply of electrical current to the motor 210 with a first polarity to cause the rotation of the cam gear 218 in a first direction from its start position illustrated in FIGS. 23-30 to the position illustrated in FIGS. 29-30 . During this movement of the cam gear 218 , the cam lobe 207 of the cam gear 218 engages the elongated prong 314 of the pawl 204 and thus rotates the pawl 204 to its second latched position relative to the housing 202 . At this point the trigger 206 engages the pawl 204 to retain the pawl 204 in the second latched position. The motor 210 continues to be energized until the cam gear 218 rotates back to its initial or starting position. At that point, the sensor 326 detects that the cam gear 218 is in its initial position and signals the control circuit 235 to shut off electrical current to the motor 210 , which stops further rotation of the cam gear 218 . The latch 200 now locks the panel 300 in its closed position. As the pawl 204 is rotated to its second latched position, a sealing gasket (not shown) is compressed to form a seal between the panel 300 and opening of the compartment closed off by the panel 300 .
If normal closing is blocked, for example by items being caught between the panel 300 and the compartment opening, after a predetermined time without a signal from the sensor 326 , the control circuit 235 reverses the current to the motor to disengage the trigger 206 from the pawl 204 by the reverse movement of the second cam 205 and the panel 300 is released and the latch 200 is returned to the initial fully unlatched configuration.
To open the latch 200 the motor 210 is energized by the user using a remotely located switch (not shown). The cam gear 218 rotates from the initial position of FIGS. 32-33 in a second direction, opposite the first direction, to bring the second cam 205 into contact with the trigger actuator lever 286 as shown in FIGS. 36-39 . The rotation of the cam gear 218 in the second or reverse direction causes the second cam 205 , acting via the trigger actuator lever 286 , to rotate the trigger 206 out of engagement with the pawl 204 in order to release the pawl 204 for rotation to the unlatched position as shown in FIGS. 38-43 . The striker 308 is now released and the panel 300 can be opened. The motor 210 remains energized until the cam gear 218 is once again in its initial position as detected by the sensor 326 . When the sensor 326 senses that the cam lobe 207 , and consequently the cam gear 218 , has returned to its initial position, the sensor 326 signals the control circuit 235 to stop energizing the motor.
Referring to FIGS. 31-33 , if the pawl 204 is moved to the second latched position as detected by the sensor 316 , while the striker detector 318 does not indicate that the striker 308 is captured by the pawl 204 , then the control circuit 235 reverses the current to the motor to disengage the trigger 206 from the pawl 204 by the reverse movement of the second cam 205 and the panel 300 is released and the latch 200 is returned to the initial fully unlatched configuration. If the motor 210 or associated circuitry fail with the latch fully latched and the panel 300 closed, the trigger lever 284 is provided with a hole 322 that allows a cable (not shown) to be attached to the trigger lever 284 as a back-up mechanical release mechanism that will be operated by a lever (not shown) from the interior of the vehicle. The cable can then be pulled to disengage the trigger 206 from the pawl 204 in order to release the pawl 204 , and consequently the striker 308 , such that the panel 300 can then be opened.
If the panel 300 is closed on the inoperable latch 200 , the striker 308 can engage and move the pawl 204 to the first latched position where the pawl 204 is held by the trigger 206 and the striker 308 is captured by the pawl slot 258 . This first latched configuration is illustrated in FIGS. 19-20 . This arrangement allows the panel 300 to be secured in a near closed position until the vehicle can be taken in for service.
During the operation of the latch 200 , the latch control circuit 235 also continuously monitors the current supplied to the motor 210 . If a sudden rise in the motor current is detected due to an unexpected load during closing, the rotation of the cam gear 218 is reversed to release the latch pawl 204 as a safety measure.
The bushing 500 is provided for supporting the end of the motor shaft 220 . In the assembly views the various springs are only shown diagrammatically.
It is to be understood that the present invention is not limited to the embodiments disclosed above, but includes any and all embodiments within the scope of the appended claims. | The present invention is directed to improvements in latch design. The illustrated embodiment of the present invention is a rotary pawl latch with the capability to provide a compressive force between the first member and the second member. The illustrated embodiment of the present invention is of an electromechanical type. The control circuit of the latch detects when a striker attached to one member, for example a door, has moved the pawl to a first latched position. A motor is then activated that drives the pawl to a second latched position to provide compression between the first member and a second member, for example a door frame. | 4 |
FIELD OF THE INVENTION
This invention relates to the monitoring of induced counterpropagating signals such as stimulated Brillouin scattering in optical telecommunications systems and the control of such systems in the presence of such induced signals.
BACKGROUND TO THE INVENTION
Optical transmission systems for telecommunications typically comprise a number of system elements connected by waveguides in the form of optical fibres, there being typically a number of bi-directional line amplifiers at spaced locations between each transmitter and receiver. Such amplifiers are necessary when long distance communication is required in order to compensate for the power loss associated with transmission through the fibres.
One of the main factors limiting the maximum power which can be launched into a fibre is the effect of stimulated Brillouin scattering, the effects of which are characterised by a counterpropagated signal which is down shifted in frequency by about 11 GHz for silica glass fibres, the onset of scattering being observed at a threshold power which can be as low as 2 mW to 3 mW.
SBS (stimulated Brillouin scattering) can be suppressed by low frequency amplitude modulation (dither) of the transmission as described in U.S. Pat. No. 5,329,396 so that the peak launched power level can be increased. In effect, this modulation enables the power spectral density of the transmission to be less than the threshold of onset of SBS. A similar effect is achieved by time varying the phase angle of transmission light waves as disclosed in U.S. Pat. No. 4,560,246. There is however some degree of degradation to the transmitted signal associated with such methods of SBS suppression so that the degree of suppression utilised is ideally kept to a minimum.
Other forms of induced counterpropagating process include Rayleigh scattering and Raman scattering. In referring to induced counterpropagating processes in the context of the present application, the intended meaning encompasses the above mentioned and similar effects associated with wavelength dependent and/or non linear sources of counterpropagating signal, generally associated with bulk properties of the waveguide material, and specifically excluding reflection from fibre defects, couplings or other discontinuities in the waveguides or components of the system.
U.S. Pat. No. 4,997,277 includes a discussion of the detection of Rayleigh scattering as a means of investigating the distributed properties of an optical fibre and the use of Brillouin light amplification to investigate optical fibre properties.
It is also known from U.S. Pat. No. 5,513,029 to provide an optical transmission system in which an optical signal is modulated with a low frequency dither signal enabling individual signal and noise components in a wavelength multiplexed system to be measured at monitoring locations in the system and wherein optical amplifiers of the system are controlled so as to be responsive to the monitored data to control the optical gain profile of the optical amplifier.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide in an optical transmission system a method and apparatus for determining the presence of induced counterpropagated signals.
It is a further object of the present invention to provide in an optical transmission system a method and apparatus of controlling an element of the system in dependence upon the determination of whether an induced counterpropagated signal is present.
It is a further object of the present invention to provide in an optical transmission system a method and apparatus of controlling the amount of stimulated Brillouin scattering suppression in dependence upon the result of determining the presence of induced counterpropagated signals.
According to the present invention there is disclosed a method of transmitting signals between a plurality of system elements connected by waveguides in an optical communications system, the method comprising the steps of:
(a) monitoring at a selected system element a transmission via a selected waveguide of a selected outgoing signal in a selected forward direction;
(b) monitoring incoming signals received via said waveguide at the selected system element in a reverse direction which is opposite to the forward direction;
(c) detecting in the incoming signals a reverse signal constituted by a component of the outgoing signal propagated in the reverse direction;
(d) determining whether the reverse signal has characteristics consistent with the occurrence of an induced counterpropagation process; and
(e) controlling the transmission of signals in said system in accordance with the results of said determining step.
Preferably the determining step determines whether the reverse signal has characteristics consistent with the induced counterpropagating process comprising stimulated Brillouin scattering associated with bulk properties of the waveguide. Preferably a power distribution of the reverse signal is measured as a function of delay relative to transmission of the outgoing signal in the forward direction. Such a power distribution, typically in the form of a reflection array, will contain diffuse features if the reverse signal originates from an induced counterpropagation process distributed along the length of the waveguide and discrete features in the form of peaks in the power distribution will correspond to discrete points of reflection, for example resulting from discontinuities in the waveguide or connectors and the like. The above use of the term "diffuse" is intended to indicate a power distribution which varies smoothly as a function of delay, relative to the sharply varying power distribution features associated with discrete reflections.
Analysis of the power distribution of the reverse signal thereby allows the presence of a scattering process to be deduced. Discrete features corresponding to discrete reflections may be removed from the power distribution data and the revised power distribution data utilized in further evaluation. The further evaluation may include a best fit calculation applied to the revised power distribution data to determine best fit coefficients of a predetermined functional relationship representative of the effects of a scattering process.
An estimate of the component of power of the reverse signal due to scattering may be calculated from the above best fit calculation and compared with a threshold to determine whether a fault condition exists.
The shape of the power distribution data, as revealed in the best fit calculation, provides a basis for identifying the source of the reverse power. An exponential decay for example is characteristic of scattering processes.
The determining step may include further stages of analysing the reverse power including an analysis of wavelength multiplexed components in the reverse power to reveal the wavelength dependence of scattering. In a typical scenario, a single component in a wavelength multiplexed transmission will largely be responsible for the fault condition in which stimulated Brillouin scattering at one wavelength results in increased reverse power relative to the reverse power of the remaining components. The reverse power for the remaining components will follow the wavelength dependence of Rayleigh scattering (P=k/λ 4 ). Stimulated Brillouin scattering may be quantitively measured by estimating the amount of Rayleigh scattering of the single component by interpolation of data for the remaining components and subtracting the estimate of Rayleigh scattering from the total reverse power measured for the single component responsible for stimulated Brillouin scattering.
The system may be controlled according to the measure of stimulated Brillouin scattering by adjusting the transmitted power, re-routing data traffic, or adjusting the degree of stimulated Brillouin suppression applied to the selected signal at which the fault condition is determined to exist.
Preferably the above steps are performed under the control of a control system without operator intervention.
Preferred embodiments of the present invention will now be disclosed by way of example only and with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic diagram of an optical transmission system in accordance with the present invention;
FIG. 2 is a flowchart illustrating overall operation of a system in accordance with the present invention;
FIG. 3 is a schematic diagram of apparatus for measuring reverse power (step 1);
FIG. 4 is a schematic diagram of apparatus for measuring the variation of reverse power with delay (step 2);
FIG. 5 is a graphical representation of,
Graph A--measured reverse power including discrete features corresponding to discrete reflections,
Graph B--measured reverse power after removal of the discrete features (step 2),
Graph C--the result of curve fitting (step 3),
Graph D--the range of delay characteristics consistent with scattering;
FIG. 6 is a schematic flowchart illustrating the identification of SBS and quantatively determining SBS power (step 4);
FIG. 7 is a graphical representation of the wavelength dependence of multiplexed signals in the presence of SBS (step 4);
FIG. 8 is a graphical representation of the variation in received power in the presence of SBS (step 5); and
FIG. 9 is a graphical representation of the variation in reverse power with transmitted power (step 6).
DETAILED DESCRIPTION OF EMBODIMENTS
FIG. 1 illustrates schematically part of an optical transmission system in which elements of the system are connected by waveguides 1 in the form of optical fibres for the bi-directional transmission of optical signals. The optical signals are boosted periodically by bi-directional line amplifiers such as the amplifier 2 which is operated under the local control of a processor 3.
In the following examples, the amplifier 2 is selected as a system element at which signal monitoring is undertaken to allow determination of system faults.
Overall control of the optical transmission system is effected by a network management system 4 which maintains overall control of the routing of data traffic and the function of the system elements including amplifier 2. In the example of FIG. 1, a single fibre waveguide 1 carries four wavelength multiplexed signals S 1 , S 2 , S 3 , S 4 from a first transmitting and receiving element 5 to a second transmitting and receiving element 6. The second transmitting and receiving element 6 transmits four further wavelength multiplexed signals S 5 , S 6 , S 7 , S 8 in the opposite direction via the waveguide 1 to the first transmitting and receiving element 5. The wavelengths of signals S 1 to S 8 are mutually different.
The processor 3 is programmed to periodically carry out a procedure to monitor the presence of induced counterpropagating signals and to take appropriate remedial action. In the following description, a procedure is described which is tailored specifically to detect and quantify the effects of SBS.
Transmission in a particular direction is selected and designated in FIG. 1 as a forward direction 7 (towards the second transmitting and receiving element), any counterpropagating signal therefore being received at the amplifier 2 by propagation in a reverse direction 8.
The amplifier 2 is provided with a conventional coupling arrangement which outputs first and second tap signals 9 and 10 which are tapped from the amplified forward direction transmission and the reverse direction transmission respectively. The tap signals 9 and 10 are detected by data acquisition circuits 11 which output respective digitised data samples representing forward and reverse power to the processor 3.
The series of steps implemented under the control of the processor 3 and the network management system 4 will now be described, referring to Step 1 to Step 6 as follows. The overall sequence of steps is summarised schematically in the flowchart of FIG. 2.
Step 1; Measurement of Total Reverse Direction Power
In Step 1, the total optical power transmitted in the reverse direction as a result of reflection of the amplified signals S 1 , S 2 , S 3 , S 4 and counterpropagation induced by the amplified signals is measured. In order to distinguish such reverse power from the total. transmission signals in the reverse direction S 5 , S 6 , S 7 , S 8 , a low frequency dither is applied to the amplified forward direction transmission by applying a square wave modulation to the bias voltage of the amplifier 2 by means of a dither generator 12 as illustrated in FIG. 3. This method of measurement is disclosed in our copending application U.S. Ser. No. 08/588,176, filed Jan. 18th, 1996, the contents of which are incorporated herein by reference. The dither frequency is in the range 1 Hz to 100 Hz which is a sufficiently low frequency for the modulation of the reverse power to remain correlated to the modulation of the forward direction power. The processor 3 calculates the ratio R 1 between the measured reverse and forward direction powers and compares the ratio with a threshold value of -30 dB, this process being represented in FIG. 3 schematically by correlator 13 and comparator 14. If the threshold is exceeded, it is concluded that unsatisfactory operation merits further investigation, thereby proceeding to step 2.
Step 2; Measurement of Reverse Power as a Function of Delay and Removal of Discrete Features
The low frequency dither of the amplifier 2 used in step 1 is discontinued and in step 2 the forward direction transmission of data is utilised as a test signal in measuring the amount of reverse power as a function of delay. The first and second tap signals 9 and 10 which are representative of the forward and reverse power are sampled at a rate of 10 MHz as shown schematically in FIG. 4 by means of detectors 15, bandwidth limited amplifiers 16 and analogue to digital converters 17 and the resulting data analysed by the processor 3 using FFT (Fast Fourier Transform) techniques. The low frequency spectral components of the forward direction signals S 1 , S 2 , S 3 , S 4 provide a signature which is detected in the second tap signal 10 by correlating the second tap signal 10 with a delayed version of the first tap signal 9. This process is illustrated schematically in FIG. 4 by function blocks within processor 3 comprising an FFT step 18 of forming FFT (fast Fourier transforms) for each of the respective first and second tap signal data inputs, a dividing step 19 of dividing the results of the FFT step and an inverse FFT step 20 of forming an inverse FFT of the results of division. The resulting data r(t), referred to hereafter as a reflection array, represents the distribution of reverse power a function of delay t, the delay being defined as the elapsed time between transmission of a signal by the amplifier in the forward direction and receiving at the amplifier the same signal propagated in the reverse direction.
The above method of obtaining a reflection array is disclosed in our copending application U.S. Ser. No. 08/793,629 filed Feb. 18th, 1997, the contents of which are incorporated herein by reference. (U.S. Ser. No. 08/793,269 is derived from PCT/GB95/01918 and correspondingly published as GB-A-2292495).
Specifically, r(t) represents the proportion of transmitted power detected as reverse power per unit of delay so that the total reverse power is proportional to the area under a graph of r(t) against t.
FIG. 5 graph A illustrates graphically a typical reflection array represented as log 10 r(t) against delay t. The graphical form is approximately a straight line, corresponding to an exponential decay, with a number of sharp peaks corresponding to discrete reflections at values of delay t 1 , t 2 and t 3 . The contribution to r(t) made by discrete reflections is revealed by the peaks in the reflection array and the processor 3 smooths the data using known algorithms by identifying and removing the peaks to provide the curve shown at graph B.
A revised estimate R 2 of the ratio between reverse and forward power is then calculated by taking the integral under the curve of graph B and the resulting ratio R 2 is compared with a threshold value of -30 dB. If this threshold is exceeded, it is concluded that unsatisfactory operation merits further investigation, thereby proceeding to step 3.
Step 3; Apply Best Fit Calculation to Reflector Array, Measure Rate of Decay and Obtain Improved Estimate of Backscatter Parameter
The processor then applies a best fit algorithm to the reflection array data r(t) assuming that r(t) can be defined by a function of the form:
r(t)=A·10.sup.-αt Equation 1
where A is the initial value of reverse power and α is a measure of the decay of reverse power resulting from a signal impulse. The function of equation 1 is consistent with the reverse power being due to a scattering process, for values of α defined below. The value of α corresponds to the slope of the logarithmic graphical representation of FIG. 5. In graph C the result of the best fit calculation is shown as a straight line. The value of α obtained by the best fit calculation is compared with maximum and minimum values α max and α min which represent the limits of α for which the result is judged to be consistent with the decay in r(t) being due to a scattering process. α max corresponds to a highly lossy optical fibre whereas α min corresponds to an extremely low loss fibre. Typical values of α min and α max are 7,200 and 24,000 respectively, corresponding to the high loss and low loss limits shown in graph D.
If α falls outside of this range, the processor 3 initiates the acquisition of further data, repeating the preceding steps to obtain an improved level of confidence in the measurement.
If a value of α within the above limits is obtained, the processor proceeds on the assumption that scattering requires further analysis.
The total reverse power is then recalculated on the basis of the coefficients A and α obtained as the best fit calculation results, the new estimate of measured reverse power being the integral under the graph C of FIG. 5 and given by the expression:
R.sub.3 =A÷α Equation 2
R 3 is a backscatter parameter which represents the ratio between measured reverse cattering power and the forward power.
The processor 3 compares the value of R 3 with a threshold value of -30 dB and, if the threshold is exceeded, it is concluded that unsatisfactory operation merits further investigation, thereby proceeding to step 4.
Step 4; Measurement of Wavelength Dependence to Confirm SBS Present, Quantify SBS and Initiate Remedial Action
A candidate signal S c is selected from forward transmission signals S 1 to S 4 as being suspected of being responsible for the induced SBS. The first transmitting and receiving element 5 is instructed via the network management system to fade out the candidate signal S c while controlling the gain of the amplifier 2 such that the transmitted power levels for each of the remaining signals S i remain unchanged. Selection of the candidate signal will generally be made by the network management system based on the detection of bit errors in data received via that particular signal. The value of
R.sub.3 (ΣS.sub.i -S.sub.c),
the backscatter parameter representing reversepower excluding discrete reflections and after best fit calculation as described above, is calculated for the signals S i excluding the candidate signal S c and the result compared with the previously calculated figure
R.sub.3 (ΣS.sub.i)
for all of the signals S 1 to S 4 . If the result shows a substantial reduction in the backscatter parameter
R.sub.3 (ΣS.sub.i -S.sub.c)<R.sub.3 (ΣS.sub.i) Equation 3
this is a strong indication that the fault condition is a wavelength specific scattering process and is taken as confirmation that SBS has been induced by the candidate signal S c . If on the other hand there is little or no change in R 3 , then S c is concluded not to be the dominant source of scattering.
If S c is found to be the source of SBS, it is assumed that the reverse power P(S c ) associated with S c is made up partly of reverse power due to Rayleigh scattering p R (S c ), in addition to reverse power due to SBS, P SBS (S c ). In order to quantify the SBS contribution P SBS (S c ), the reverse power P(S c ) associated with the candidate signal S c is estimated by measuring the reverse power components P(S i ) from each of the remaining signals and interpolation on the assumption that the reverse power components follow a wavelength dependence consistent with Rayleigh scattering and given by:
P.sup.R (S.sub.i)=k/λ.sup.4 Equation 4
where P R (S i ) is the reverse power due to Rayleigh scattering for signal S i ,
k is a constant, and
λ is the wavelength of signal S i .
A suitable method of conducting such measurement of P(S i ) is to select in turn each of the transmitted signals and to apply dither to the selected signal S i . The reverse power P(S i ) is then correlated with the dither waveform to effect a power measurement which is sensitive only to the selected signal S i . This measurement can be repeated in turn for each signal S 1 to S 4 . Alternatively, mutually orthogonal pseudo-random dither sequences may be applied simultaneously to all of the signals S i and the correlator provided with spectral templates for each of the dither waveforms to enable the power components P(S i ) of each signal to be individually identified. Such a method is analogous to the method of applying dither to signals disclosed in U.S. Pat. No. 5,513,029.
FIG. 7 illustrates graphically the relationship between the reverse power components P(S i ) of the remaining signals which follow the wavelength dependence of Rayleigh scattering, the candidate signal S c in the example shown being equal to S 3 and the SBS contribution to reverse power P SBS (S 3 ) is seen to be the difference between the measured reverse power component P(S 3 ) for signal S 3 and the interpolated value I(S 3 ) of reverse power due to Rayleigh scattering of the signal S 3 .
The processor 3 is thereby able to calculate and output an estimate of the reverse power P SBS (S c ) due to SBS for the candidate signal, thereby enabling the network management system 4 to implement appropriate remedial action which may include generation of an alarm signal. Other actions may include a reduction in the transmitted power for the candidate signal S c to a level at which SBS is reduced or eliminated. Alternatively, an increased amount of SBS suppression may be applied by the first transmitting and receiving element 5 to the candidate signal. In cases of severe deterioration, it may also be appropriate for the network management system 4 to re-route the data to avoid use of the candidate signal S c in the waveguide 1 pending further investigation and repair.
As described above, removal of the candidate signal S c from transmission requires gradual fading out of the candidate signal by controlling the optical power output by the first transmitting and receiving element 5 at the wavelength of the candidate signal. Such gradual fading is necessary to avoid transients in power level occurring in elements of the system, as for example in the case of an erbium doped fibre amplifier handling several signals at different wavelengths where the effect of removing one of the signals would be to increase the amplification applied to the remaining signals. The resulting transient, typically with a time constant of the order of microseconds, typically produces sufficient change in total optical power to result in bit errors. As described in co-pending application U.S. Ser. No. 08/735759 filed Oct. 23rd, 1996 titled "Stable Power Control for Optical Transmission Systems", the contents of which are incorporated herein by reference, the provision of gradual fade-out (or fade-in) of a signal at a particular wavelength in a wavelength division multiplexed signal allows automatic gain control circuits to adjust the pump power of optical amplifiers operating on the remaining signals at other wavelengths in the system, thereby minimising the likelihood of bit errors occurring. The time constant of the gradual fade-in or fade-out is typically of the order of 60 seconds. This fading function may for example be supervised by a local microcontroller at the transmitter, the microcontroller being operable to intercept an instruction to turn off one of the component signals and implement a routine which gradually fades the signal by controlling a gain or attenuation stage within the transmitter module.
A method of adjusting the gain of amplifier elements in the system to maintain the original power levels of the remaining signals when the candidate signal is removed is disclosed in our co-pending application U.S. Ser. No. 08/715662 filed Sep. 18th, 1996, the contents of which are incorporated herein by reference. The disclosed method selects the remaining signal having the strongest power level, the output transmitted for the wavelength of the selected signal being dithered and the amplifier output monitored and correlated with the dither in order to measure the component of optical power corresponding to the selected signal. A control loop then regulates the gain of the optical amplifier to maintain the power of the selected signal at a constant value. Such a method overcomes the problem that an optical amplifier multiplying a multiplexed set of signals of different wavelength will tend to regulate the total power output and will therefore react to removal of one signal by increasing power in the remaining signals.
The above described steps 1 to 4 may be completed without degrading the performance of the system with respect to the remaining signals other than the candidate signal. Furthermore, the above steps may be performed automatically under the control of the processor 3 and the network management system 4 without manual intervention. It is envisaged that for most situations, remedial action may be effected automatically and without the intervention of an operator. There may however be circumstances under which supervisory intervention is necessary, in which case the procedure of the following additional steps may be followed.
Step 5; Measurements Using The Candidate Signal Alone
Starting from the position that the presence of SBS, or some other induced counterpropagating signal, has been detected for transmission in a particular direction at a particular amplifier and associated with the candidate signal S c , further investigation to provide evidence that the counterpropagating signal is consistent with SBS requires removal of the remaining multiplexed signals in the selected direction so that the received power at the next receiver can be measured as a function of transmitted power. As shown in FIG. 8, the presence of SBS causes the received power to level off in a characteristic manner and at a characteristic power level. Other forms of induced counterpropagating signals, such as Raman scattering, tend to occur at higher power levels than those at which SBS becomes dominant, Raman scattering also being substantially wavelength independent.
To obtain a measurement curve as shown in FIG. 8, each of the remaining signals in the forward direction is faded out gradually to avoid transients (in the manner described above with reference to fading out the candidate signal) and the transmitted power of the candidate signal set to its minimum value, for example -30 dBm. The resulting power received at the next point of measurement is then measured in the selected direction. The transmitted power setting is increased in suitable steps, for example 0.25 dB, and the received power values again measured. In the absence of the remaining signals, the power which can be injected at the candidate signal wavelength can be increased beyond normal limits, thereby enabling any deviation in linearity to be detected at high power levels. The degree of SBS may thereby be measured as the difference in power level between the normal power level of the transmitted candidate signal and the power level at which the onset of SBS is detectable.
If however the above-described procedure of step 5 has been completed without revealing the characteristic non-linear SBS deviation in power characteristic, further investigation is required according to the following step 6.
Step 6; Measurement of Reverse Power for a Range of Transmitted Power Values Using The Candidate Signal Only
The method described above with reference to steps 1, 2 and 3 may be used to measure the reverse power, excluding the effects of discrete reflections, when only the candidate signal is transmitted, after having faded out the remaining signals. The transmitter may then be controlled to adjust the transmitted power through a series of steps allowing the reverse power to be measured at each step and allowing an evaluation of the linearity of a graph of reverse power against transmitted power. A typical graph in the presence of SBS is shown in FIG. 9.
A comparison of the normal power of the candidate signal with the power at which the onset of non-linearity or SBS is observed allows parameters to be extracted to indicate the performance margins of the system. In the example of FIG. 9, the power at which the onset of SBS occurs is greater than the normal power of the candidate signal by a difference which is the margin before the onset of SBS. If the normal power of the candidate signal is greater than the power at onset of SBS, the difference is a measure of the degree of SBS as in the example of FIG. 8.
Results extracted by the above method may be used to control parameters of elements of the system, for example, the amount of margin can be used to adjust the strength of SBS suppression or the peak power setting of the amplifier can be adjusted in order to obtain the required margin before onset of SBS.
The extracted results can be compared to thresholds and alarms or status indicators raised appropriately.
Although the above description refers to SBS and its characteristics, the method may be adapted to detect other forms of non-linearity in the transmission of optical signals, or wavelength dependent reflections, by adjustment of the exponential fit described in step 3.
A system in accordance with the present invention may be programmed to systematically carry out the above described diagnostic measurement steps and take appropriate remedial action. Some of the steps may alternatively be omitted, as for example steps 5 and 6. Steps 1 to 4 may alternatively be simplified, for example by omitting the initial step 1. | An optical communications system has a control system for controlling the transmission of signals between system elements via waveguides. The occurrence of counterpropagation occurring due to scattering or other bulk properties of the waveguides is monitored under the control of the control system at selected system elements such as bidirectional optical amplifiers. A reverse signal found to be consistent with a scattering process is analysed in terms of a power distribution as a function of delay relative to transmission of an outgoing signal and any effects due to discrete scattering events are identified and removed from the power distribution data. The revised data is used to quantify the effects of the scattering process. Stimulated Brillouin scattering is identified by analysis of backscatter in terms of wavelength of selected signals in a wavelength multiplexed transmission and the control system responds by regulating operating parameters of the system such as the degree of stimulated Brillouin scattering suppression and transmission power. The system is thereby able to automatically detect the occurrence of faults associated with bulk properties of the waveguides of the system and initiate appropriate remedial action or raise alarms. | 7 |
CROSS REFERENCE TO RELATED APPLICATION
This application is a continuation of application Ser. No. 07/098,595, filed Sept. 17, 1987, now abandoned.
BACKGROUND
In large computer systems, numerous printed circuit assemblies (PCA) are connected together at a computer backplane. Each PCA may be individually modified and updated. This modification is typically not discernable from the appearance of the PCA. Therefore, information is often placed on a label on the PCA.
Often the modification or update of one PCA in a computer system may require modification of one or more PCAs in the computer system in order for the computer system to function properly. Therefore, in order to update one PCA it may be necessary to examine several PCAs in order to determine versions of which PACs are extant in the system. This can be extremely time consuming and inconvenient.
Additional problems arise when PCAs are remotely update. That is, updating certain PCAs may not require the exchanging of hardware but only the replacing of software. The replacement software may be transferred through telephone lines and installed in a PCA without a service representative being required to visit the cite of the computing system. In this case, however, the service representative would be unable to read the labels on other PCAs within the computing system. Further, he would be unable to relabel the updated PCA
SUMMARY OF THE INVENTION
In accordance with the preferred embodiment of the present invention, a method and apparatus for tracking and identifying printed circuit assemblies is presented. Within each printed circuit assembly is a non-volatile random access memory (RAM). Within each RAM is stored information about the printed circuit assembly, including the current revision level of the assembly. This information may be accessed by a user through a dedicated bus and hardware designed for this task. Additionally, through the dedicated bus and hardware, the user may update the information within the printed circuit assembly.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a block diagram of various printed circuit assemblies coupled to each other through a bus in accordance with a preferred embodiment of the present invention.
FIG. 2 shows how certain of the printed circuit assemblies in FIG. 2 may be arranged in slots in a cabinet.
FIG. 3 shows an embodiment of an interface which exists in each printed circuit assembly shown in FIG. 1, which is used to access the bus also shown in FIG. 1.
FIG. 4 and FIG. 5 show various timing diagrams describing data flow to and from the interface shown in FIG. 3.
FIG. 6 is a block diagram of processor development hardware in accordance with the preferred embodiment of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 shows a bus 100. Bus 100 is wholly dedicated to transfer informationdescribing printed circuit assemblies (PCA). Shown coupled to bus 100 are the following PCAs: a bus converter 101, a bus converter 102, a memory controller 103, a memory controller 104, a memory array 105 and a memory array 106 which are representative of sixteen memory arrays, a processor 122, a processor 123, a processor 124, a processor 125, a power system monitor 126, processor development hardware (PDH) and a clock 128.
Typically the PCAs shown in FIG. 1 will be mounted in a computer cabinet. FIG. 2 shows how processor 122, processor 123, processor 124, processor 125, power system monitor 126, PDH 127, bus converter 101, bus converter 102 and memory controller 103 might be placed within slots in a computer cabinet 130.
Each PCA shown in FIG. 1 contains a special interface to bus 100. A block diagram of this special interface is shown in FIG. 3. The interface consists of four chips interconnected as shown. Chips 201, 202 and 203 aremanufactured by Texas Instruments Incorporated, P.O. Box 225012, Dallas, Texas 75265. Chip 201 has a part number 75ALS520. Chip 202 and chip 203 have a part number 74ALS240N. A chip 204 is a 16×16 Bit Serial Nonvolatile Static RAM produced by Xicor Inc., and has a part number X2444.
Data bus 100 includes the following lines from the interface of each of thePCAs connected to bus 100: lines 205, 206, 207, 208, 209, 219, 221, and 239. Each of these lines are interconnected to the bus, and thus are interconnected with corresponding lines from interfaces in each of the PCAs connected to bus 100. Lines 241, 242, 211, 228 and 229 are all set ata logic 1. Lines 243, 220, 223, 224 and 225 are all set at logic 0. Lines 244, 245, 246, 234, 236, 237, and 238 are not connected. Lines 212, 213, 214, 215 and 216 give a uniqu five-bit address for each PCA. This unique five-bit address is determined by the slot the PCA is placed in. The unique address allows each PCA to be addressed individually.
Bus 100 is controlled by PDH 127. The following is a description of how PDH127 interacts with the interface circuit shown in FIG. 3, and thus with theinterface circuit in each of the interfaces within PCAs coupled to bus 100.
PDH 127 places a five-bit address on lines 506, 507, 508, 509 and 510. PDH 127 raises line 205 to a logic 1 . . . Chip 201 checks to see if the address on lines 506-510 matches the unique five-bit address on lines 512-516. If so, line 205 is activated to logic, 0, enabling chip 203. Chip202 is always enabled; therefore, chip 202 receives the logic 0 at line 218, inverts the signal, and through line 227 enables chip 204. Once chip 204 is enabled, chip 204 is able to read a clock signal which PDH 127 places on line 219 and a data signal which PDH places on line 221. These signals are inverted by chip 202 and placed on lines 230 and 231 respectively. Additionally, once chip 203 is activated, chip 204 may transmit data to PDH 127 by placing the information on line 240. This information is inverted by chip 203 and placed on line 239, where it is read by PDH 127.
Chip 204 is able to contain 32 bytes of information. In the preferred embodiment the following information is stored by each PCA: an assembly number which indicates the type of board, e.g., memory array, processor, etc.; a date code which indicates what revision of the board currently resides in the PCA; A hardware identification number which is used to define the processor type, a serial number for the board, a division number, which indicates the company division which manufactures the board;boot idenification number, which indicates which board will boot the system; and a software identification number which further defines the processor type. In addition a byte is reserved to store the unique five-bit address of each PCA. In the current embodiment, the Assembly number requires five bytes, so the last byte of address 0010, is reserved for PDH 127. However, this information is not actually stored in chip 204 because the information is already available to PDH 127. The following table lists how the information is arranged in sixteen 16-bit words storedin chip 204.
TABLE 1______________________________________ADDR INFORMATION STORED______________________________________0000 Assembly Number0001 "0010 "0011 Date Code0100 Hardware Indentification Number0101 "0110 Serial number0111 "1000 "1001 Division Number1010 Boot Identification Number1011 "1100 Software Identification Number1101 "1110 Unused1111 "______________________________________
The following explains how chip 204 receives and sends information. More complete information is available from the data sheet for this part.
FIG. 4 is a timing diagram indicating how data may be accessed from chip 204. FIG. 4 shows a clock signal (RCLK+) 401 which is placed on line 219, an input siganl (RDIN+) 402 to chip 204, which is placed on line 221, and a output singal (RDOUT+) 403 which is placed on line 239. As can be seen from FIG. 4, chip 204 sends or receives on bit of information per clock cycle. After being enabled chip 104 looks for a command start bit 404. These are followed by four bits 405 indicating an address within the memory array within chip 204. The address is followed by 3 bits 406 which contain a command. This command may be a "read" or a "write" or a general command which specifies chip 204 to perform some function internally. If the command is a read, as in FIG. 4, data is accessed from chip 204. Immediately upon receiving a command to read chip 204 places a first byte 407 and a second byte 408 on line 240 through chip 203 to line 239. First byte 407 and second byte 408 contain data stored within chip 204 at the address specified by bits 405.
FIG. 5 is a timing diagram indicating how information may be stored by chip204. FIG. 5 shows clock signal 401 and input signal 402 as they are used towrite data into chip 204. After being enabled chip 204 looks for a command start bit 504. These are followed by four bits 505 indicating an address within the memory array within chip 204. The address is followed by 3 bits506 which contain a command. If the command is a write, as in FIG. 5, data is written to chip 204. Upon receiving a command to write, chip 204 continues to reads a first byte 507 and a second byte 508 on line 240 which are placed on line 221. First byte 507 and second byte 508 contain data to be stored within chip 204 at the address specified by bits 505.
FIG. 6 shows a block diagram of PDH 127. A bus interface 601 essentially comprises the interface shown in FIG. 3. Bus interface 601 is coupled to bus 100 through lines 605. Additional circuitry 602 is shown coupled to lines 605 through lines 606. It is through lines 606 and their associated drives within additional circuitry 602, that PDH 127 communicates with PCAs connected to bus 100. PDH 127 communicates with computer system circuitry 603 through lines 607. Computer system circuitry 603 may includesome or all of the PCAs shown in FIG. 1. Although PDH 127 controls data flow through bus 100, PDH 127 receives instructions from computer system circuitry 603 as to what information PDH 127 should require to be accessedor stored. Ultimately a User (not shown) queries computer system circuitry 603 as to biographical information about PCAs within the computing system.For instance a user may do so by using a terminal 604 coupled to computer system 603 through line 608. Computer system circuitry 603 through lines 607 requests PDH 127 to find this information. PDH through lines 606 requests this information from the PCAs through bus 100.
Since bus 100 is not a high speed bus it may be optimal for PDH 127 to request information from each PCA at start-up time. PDH uses bus 100 to secure the biographical information from each PCA, this information may bestored in a memory 607. When biographical information is requested, PDH 127may access this information from memory 607, saving the time required to access this inforamtion through bus 100. | A method and apparatus for tracking and identifying printed circuit assemblies is presented. Information about each printed circuit assembly (PCA), including the current revision level of the PCA is stored within a non-volatile random access memory (RAM) within each PCA. The stored information may be accessed by a user through a dedicated bus and hardware designed for this task. Additionally, through the dedicated bus and hardware, the user may update the information within the printed circuit assembly. | 6 |
PRIORITY CLAIM
[0001] This application claims the benefit of priority under 35 U.S.C. §119(e) to U.S. Provisional Application No. 63/673/263, filed on Apr. 20, 2005, entitled “Fast Elasticity Modeling and Numerical Solutions of Seismic Un-Faulting”, invented by Kaihong Wei.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] This invention relates generally to the field of seismic interpretation, and more particularly, to modeling the restoration of a seismic fault.
[0004] 2. Description of the Related Art
[0005] Faults in the crust of the earth cut through the sedimentary strata and offset them. Consequently, the seismic features in a 3D seismic dataset are often broken at faults. Seismic interpreters often struggle to correctly correlate features in a formation resulting from seismic events across a fault. A seismic fault can distort the depositional characteristics of a formation and even obscure hydrocarbon reservoirs that may be present and recoverable. Therefore, a way to image seismic formations that effectively compensates in reverse for fault movement is highly desirable. An advantageous result of such a method would provide a representation of the seismic formation that is restored to the pre-faulting state. Such a virtual reversal, or restoration, of a fault line may also reveal characteristics of the geological deposition and aid in identifying and locating hydrocarbon reservoirs. Thus 3D fault restoration involves removing the offset of seismic features in a 3D volume in order to facilitate the study of faulting sequences and in result, analyzing pre-faulting depositional environments.
[0006] The throw of a fault at the crossing of an event (e.g., an interpreted horizon) may be defined as the offset introduced into that event (in cross section) by the fault. Such an offset defines a slip vector at that point on the fault face. Event offsets may differ along the fault face; i.e., the slip vectors are not constant. Reversing a fault in general requires, therefore, the calculation of slip vectors at several events in the cross section.
[0007] Fault faces and the borders of a cross-section define the boundary of a mechanical continuum. When a load, in terms of traction or displacement (slip) vector, is applied to the boundary such as a fault surface, each point in the continuum will be displaced. The continuum will be deformed. Elasticity theory states that at equilibrium under loading, the total strain energy of the deformed region is—among all possible deformation for the given load—at a minimum. Or, equivalently, the theory states that the virtual work done by any admissible deformation is zero.
[0008] Rutten (Rutten, Kees, The Slokkert Validator Documentation, Landmark Graphics Internal Technical Communication, 2002) presented an algorithm to solve the same problem of fault restoration. When a number of slip vectors on a fault trace were given to reverse faulting, Rutten used a piecewise linear function to define the slip function on the fault surface. The approach is known as the “slip-parallel deformation model” in structural geology. In that method, the vertical displacement is attenuated, moving away from the fault, by applying a simple decay function along a set of scan lines intersecting with the fault. The results of that approach, although they may appear visually reasonable in 2-D views, lack a mechanics-based foundation. Additionally, the dispersion formulation may be complicated in practice for 3-D cases.
[0009] Elasticity theory combined with finite element methods or boundary element methods have been used to study the mechanics of faulting process (see Wei, K. and De Bremaecker, J.-Cl., A Replacement for the Coulomb-Mohr Criterion, Geophysical Research Letters, 19, 1033-1036, 1992; Wei, K. and De Bremaecker, J.-Cl., Fracture Under Compression: The Direction of Fracture Initiation, International Journal of Fracture, 61, 267-294, 1993; Wei, K. and De Bremaecker, J.-Cl., Fracture Growth Under Compression, Journal of Geophysical Research, 99, 13871-13790, 1994; Wei, K. and De Bremaecker, J.-Cl., Fracture Growth-I. Formulations and Implementations, Geophysical Journal International, 122, 735-745, 1995; Wei, K. and De Bremaecker, J.-Cl., Fracture Growth-II. Case Studies, Geophysical Journal International, 122, 746-754, 1995). The focus of these studies was to understand the orientation of fault growth for a given loading. However, solving the problem of 3D fault restoration is not the same problem as understanding how a fault grows. Therefore, fault growth models are of limited significance in 3D fault restoration—even when the goal of the restoration is to provide a mechanically sound method.
[0010] The problem of restoring a fault line is not trivial to solve because a restoration must be obtained in a mechanically and geologically plausible manner. In other words, the restoration model for displacement on the fault surface (i.e., for reversing a faulting event) must provide for dispersing mechanical energy to other parts of the region in consistency with a coherent mechanical model. The model should generally be based on assumptions that are available for validation, although it must be remembered that the goal of the restoration is not a reverse modeling of the actual faulting event.
[0011] Additionally, it would be useful if such a restoration of a seismic fault could be performed in an interactive manner, such that numerous iterations of various parameters and assumptions could be tested in an economically feasible timeframe.
[0012] Furthermore, the desirable method should provide the ability to perform a transformation on fault data in 3D, at least because 3D solutions for fault restoration are closer to geological reality and provide more accurately restored structures than 2D restorations. For 3D fault reversal problems, existing methods (such as the displacement extrapolation with scan lines) are overly simplified and cannot handle the infinite combinations of the azimuth and dip of the fault surface. The applications of 3D fault restoration are basically the same as for 2D fault restorations (see Wei, K. and Maset, R., Fast Fault Reversal, Expanded Abstract of 75 th Annual International Meeting, Society of Exploratory Geophysics, Expanded Abstracts, 24, 767-770, 2005), namely for validating the correlations of interpreted horizons, for studying the structural geology, and for interpreting pre-faulting stratigraphy. However, the advantage of a 3D restoration is that out-of-plane slip vectors can be appropriately taken into account. (Note that horizon is a term that refers to a sub-surface, usually is the top or bottom of a deposition layer, which was continuous before faulting. When a faulting occurred, a horizon was broken into two pieces on each side of the fault.)
[0013] An example of a prior art method illustrating a 2D restoration is shown in FIG. 1 . The fault is represented by the slip between sections 101 and 103 . A horizon is shown as layer 104 . 2D plane 102 intersects the formation parallel to line A′A 108 . The slip surfaces of the fault are given by 105 and 106 . FIG. 1 illustrates, that even in this simple case, the out-of-plane slip vector of the faulting cannot be accurately accounted for by applying a 2D restoration, such as given by plane 102 . Typical faults are vastly more complex than as shown in FIG. 1 ; thus a 2D restoration method is very limited in scope, and ergo usefulness.
[0014] Thus, for accurately restoring the state near a fault to conditions before the fault occurred, a 3D numerical method is required for performing the necessary calculations that is computationally efficient, and whose assumptions and models are mathematically and mechanically valid.
SUMMARY
[0015] Embodiments of the present invention address the foregoing requirements by formulating the deformation problem in 3D to numerically reverse the seismic faulting using an elasticity model, and then, numerically solving the deformation problem with a numerical method in 3D. Thus, one embodiment comprises an elastic physical model for formulating the problem and a numerical method for obtaining a solution. Therefore, a novel restoration solution that is mathematically and mechanically coherent is provided.
[0016] One embodiment uses an elasticity model as the unifying approach for both 2-D and 3-D coordinates, and in result, delivers a consistent solution for all cases. The physical model disperses the slip vector from the fault surface to other parts of the region in consistency with an elastic deformation model. This provides for the handling of faults in a complex geometry, and may easily be extended from 2-D to 3-D cases. One embodiment also comprises a special technique that solves the finite element equation and a boundary element equation in a very efficient manner such that the technique can be used in an iterative and interactive way. Thanks to the special numerical technique, the method may provide the computational performance necessary for interactive graphical operations. This enhanced computational performance allows users of the method to quickly and graphically experiment with many seismic scenarios while obtaining geologically consistent interpretations and images. Examples may be used to validate the method, and the underlying theory dictates minimal distortion of markers, such as seismic reflectors, within the restored volume sections.
[0017] The methods described herein may be applied to theoretical or measured seismic data sets and assumes that a known fault surface in a seismic formation does not change during the 3D restoration. The formulation of the problem is based on the well-known principle of virtual work (also known as the D'Alembert's-Lagrange principle and is equivalent to Newton's second law), which states that at equilibrium, the work done by any virtual displacement must be zero. In one embodiment, the virtual displacement is constrained along the surface of the fault, such that the deformation of the volume results in the minimum strain energy among all admissible deformations.
[0018] Once a formulation of the 3D restoration problem has been created, the problem may be solved to yield the 3D restoration solution. For solving the problem numerically, the method may decompose the boundaries of the faulting volumes into small elements of a simple geometry. The decomposition of the surface into small elements is performed in one embodiment of the present invention using elements corresponding to a general triangle, each of which comprises 3 vertices and a surface area.
[0019] Upon decomposition into small elements, the boundary integrals can be expressed as the sum of the integrals on these small elements. Furthermore, the displacement and traction functions on the small elements may be approximated with simple functions, such as linear functions. These simple functions may be parameterized with the displacement and traction value at the vertices of an element. In this manner, the integrals on an element become a linear combination of the displacement or traction value at the vertices. After assembling the integrals, a boundary element equation on the displacement and traction at the vertices of a boundary may be obtained. When certain restoration slip vectors are specified on the fault surface, the deformation of the volume can thus be solved with any prescribed traction on the other, non-fault boundaries. The remaining slip vectors on the fault surface are resolved in enforcement of a space constraint. A solution comprising the pre-faulting seismic state of an entire volume adjacent to a fault surface can thus be obtained.
[0020] The method may further apply a space constraint to the formation surfaces on each side of the fault surface, such that points on the surface model may not overlap each other as a result of the restoration. The space constraint, which may be enforced using a repulsive or attractive stress applied normal to the surface of an element, may be iteratively applied to generate an acceptable result within a minimal spatial tolerance.
[0021] The method thus may provide a numerical result that represents the un-faulted, i.e., 3D restored, state of the formation. Seismic events may be so restored to a pre-faulting state, and interpretation and stratigraphic analysis can then be carried out with great efficiency and high accuracy. The utility of the embodiments described herein may further extend to providing 3D restoration results in a form that may be readily used for display, storage, reporting, testing, assessments and further numerical analyses; for example, the results may be extremely useful for further simulation, modeling, or validation involving theoretic or experimental seismic data.
[0022] The foregoing has outlined rather broadly the features and technical advantages of embodiments of the present invention in order that the detailed description of the invention that follows may be better understood. Additional features and advantages will be described hereinafter, which form the subject of the claims of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] A better understanding of the present invention can be obtained when the detailed description presented herein is considered in conjunction with the following drawings in which:
[0024] FIG. 1 illustrates an example of a prior art 2D restoration method;
[0025] FIG. 2 illustrates restoration slip vectors in a 3D fault event in an embodiment of the present invention;
[0026] FIG. 3 illustrates a 3D fault surface in an embodiment of the present invention;
[0027] FIGS. 4 and 5 illustrate a finite element model of volumes on either side of a fault surface in an embodiment of the present invention;
[0028] FIG. 6 is an image of a cross-section of a highly faulted formation;
[0029] FIG. 7 is an image of a cross-section of a highly faulted formation restored in 3D in an embodiment of the present invention; and
[0030] FIGS. 8-12 illustrate flowcharts of a method in an embodiment of the present invention.
[0031] While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and are herein described in detail. It should be understood, however, that the drawings and detailed description thereto are not intended to limit the invention to the particular form disclosed, but on the contrary, the intention is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the present invention as defined by the appended claims.
DETAILED DESCRIPTION
[0032] In the following description, numerous specific details are set forth such as specific reference algorithms to provide a thorough understanding of embodiments of the present invention. However, it will be obvious to those skilled in the art that embodiments of the present invention may be practiced without such specific details. In other instances, well-known mathematical method steps or components have been omitted or shown in block diagram form in order not to obscure the present description in unnecessary detail. For the most part, details concerning specific timing considerations and the like have been omitted inasmuch as such details are not necessary to obtain a complete understanding of the methods described herein and are within the skills of persons of ordinary skill in the relevant art.
[0033] One embodiment of the invention formulates the deformation problem to remove subsurface faulting fault with an elastic model and solves the deformation problem by a numerical method, such as a volume element or boundary surface element method. The method provides for computing the deformation due to the reversal of faulting on a section or a volume in a mechanically coherent manner. In one embodiment of the present invention described below, a boundary surface element method is used. Since the boundary surface element method generally requires fewer vertices than a volume element method for a given volume section, it can be generally expected to execute much faster than a volume element method. Embodiments may be practiced with a volume element method in alternate embodiments using essentially the same basic method steps as presented for the boundary surface method.
[0034] With a boundary element method, the fault surface divides a volume into two sections. A multiple subsection scheme is employed in cases where two sections are partially coupled if the fault does not entirely or completely cut through the volume. For each section, the boundary of the section is partitioned into surface elements, and a boundary integration equation may be established based on mathematical formulations of linear elasticity. The boundary equations may then be numerically solved for given slip or displacement vector on the fault surface, and the deformation solution to the fault reversal is obtained by a numerical integration over the boundary of each section. Note that the same fundamental integration equations are established for each section in 2D cases as those in 3D cases. By solving these integration equations numerically, embodiments of the present invention may obtain the deformation at any interior point of the volume. Thus the seismic events in the volume may be restored to a pre-faulting state.
[0035] Refer now to the drawings wherein depicted elements are not necessarily shown to scale and wherein like or similar elements are designated by the same reference numeral through the several views.
[0036] In FIG. 2 , a simple model of a fault event 200 is illustrated in 3D. The fault event 200 comprises the slippage of a volume section 203 relative to another volume section 201 . A horizon 204 has become discontinuous as a result of the slippage. In this simplified 3D model, the planes of the surfaces 205 and 206 define the fault. The restoration slip vectors, which indicate the displacement required to restore the fault on the fault surface are shown by vectors 212 for surface 205 , and by vectors 210 for surface 206 . The vectors 212 and 210 may be defined from the discontinuity of the horizon 204 , and used as inputs, i.e., known quantities, for solving the formal numerical equation (see Equation (3)). Even in this simple 3D model, the inadequacy of a model employing a 2D, i.e. planar, fault surface is easily recognized (refer to FIG. 1 ); a 2D fault surface cannot accurately account for the slip vectors in the formation, and will produce false results in a 3D restoration. However, the 3D fault surface methods will be equally accurate if the fault surface occurs only in 2D. Since, as a practical matter, most seismic fault surfaces may be assumed to occur in 3D, the methods presently disclosed are highly pertinent to realistic applications. Note that for the other parts of the fault surface, no restrictions for displacement other than the non-violation of the space constraint are applied.
[0037] In FIG. 3 , a model 300 of a volume intersected by a 3D fault surface is illustrated in 3D. The fault surface 306 divides the volume into sections, 304 and 302 , on either side of surface 306 . In other words, section 304 and section 302 contact each other along the fault surface 306 . Faces or partial faces of the volume and the fault surface 306 bound each section 304 , 302 . For each of the two sections 304 , 302 , a boundary element model is applied to decompose the boundary into small elements of a simple geometry. In one example implementation, a standard triangulation algorithm decomposes the known fault surface into a plurality of general triangles. Such triangulation functions are well known in the art for finite element analysis, and may employ any one of numerous rules and/or methodologies for establishing a decomposition algorithm. One example of a triangulation method often used in finite element methods is the Delaunay triangulation, in which no point, i.e. vertex, lies inside the circumcircle (or in 3D, the circumsphere) of any other triangle. Other regular or irregular triangulation methods may alternatively be implemented in a similar manner in various implementations of the present invention.
[0038] When the two volumes on either side of the fault surface (for example, sections 304 , 302 along surface 306 ) are displaced, such as during restoration, the contact boundaries may not overlap or penetrate each other, according to the presently disclosed methods. In other words, the contact boundaries are subject to a space constraint. A space constraint refers to fact that the two volumes must not penetrate each other. Since the two volumes contact each other along the fault surface, the constraint is imposed on the contact vertices of each volume (for example the vertices on surface 402 and surface 502 ). Repulsion is a traction or force per unit area, i.e., a stress, and it may be applied to the contact vertices to enforce the constraint. This represents a stress vector in the direction normal to the element (in the present example triangle) surface of a contact vertex and of a magnitude large enough to prevent an overlapping or an opening. In the direction of the normal vector at a contact vertex, the magnitude of the stress vector is positive or negative, arbitrarily for repulsion or attraction, and may be iteratively resolved until some minimum value satisfying the space constraint is converged upon. In some instances, the repulsion or attraction stress may be zero. The space constraint is a separate criteria for the 3D restoration results and is independent of decomposition geometry or other algorithms used in implementing various method steps.
[0039] In FIG. 4 , a volume element 400 illustrates a triangulated boundary surface corresponding to section 304 (refer to FIG. 3 ). In volume element 400 , surface 402 is the surface bounded by the fault surface 306 (not shown in FIG. 4 ). Similarly in FIG. 5 , a volume element 500 illustrates a triangulated boundary surface corresponding to section 302 (refer to FIG. 3 ). In volume element 500 , surface 502 is the surface bounded by the fault surface 306 (not shown in FIG. 5 ).
[0040] The examples presented describe application of an embodiment of the method of the present invention. In one example, corresponding to FIG. 2 , a volume of 16×16×8 m 3 is used. A fault, consisting of two planar surfaces, is introduced to the volume. The first planar surface dips 45 degrees W and strikes 0 degrees (i.e., N-S). The second planar surface dips 45 degrees SW and strikes N45W. In this example, a constant restoration slip vector is applied to every point on the first planar surface of the upper fault block. The restoration vectors have equal x- and z-components and zero y-component and represents sliding of the upper fault block against the fault surface. Note that the y-axis is parallel to the N-S compass direction and the z-axis is positive downward. The x-axis is perpendicular to the plane containing the directions of the x and z-axes. The restoration vectors are based on restoring a particular horizontal line on the fault surface, a line that represents the intersection of a horizontal horizon and the fault surface. Many points on the fault surface, but not those on the intersection, may be subject to an inequality constraint, and the repulsion method is used to enforce the constraint. The boundary of the fault blocks other than the fault surfaces are under a given traction in order to maintain equilibrium of forces involved. In this test, zero traction is used to simulate the case of no resistance to restoration. Where a portion of the fault is a planar surface, the deformation of the fault block consists only of space translation, resulting in no strain.
[0041] In another example, corresponding to FIGS. 3-5 , the volume remains the same, and the fault is now a curved surface with opposite curvatures in two orthogonal directions. The strike and dip of the fault vary from vertex to vertex. Since the fault surface is curved, the restoration results in strain in the fault volume. FIG. 3 shows a graphical representation where the red surface is the fault surface. In FIG. 4 , the fault surface of one section, the upper fault block, is exposed to the view, while the opposing section, the lower fault block, and the fault surface are made invisible. A few slip vectors may be graphically selected along a curved line on the fault surface. This curved line can be the intersection of a horizon with the fault surface. The restoration slip vectors are so chosen that the upper fault block will be restored to a higher position, and this fault block will remain in full contact with the fault surface. Note that the fault surface of the upper block is subject to the space constraint (i.e.; the repulsion method is applied), and the slip vector is defined at only a few locations. To enforce the space constraint, the repulsion scheme is applied in an iterative way. At any particular iteration, the penetration (or gap) of the vertices of elements under space constraint is computed, and an appropriate repulsion is applied to counter the space violation. An average violation is also computed, and the iteration stops when the average violation is less than a prescribed threshold. The following table shows the average space violation in m across the fault surface vertices for 16 iterations in one example method:
1 2 3 4 0.0252796 0.0129175 0.0115803 0.0105302 5 6 7 8 0.0096753 0.0089889 0.0084232 0.0079434 9 10 11 12 0.0075258 0.0071405 0.0068051 0.0065488 13 14 15 16 0.0063128 0.0060768 0.0058702 0.0056896
As one can see from the table, the penetration reduces from 0.0252796 m to 0.00568962 m after 16 iterations. The uniform convergence is a validating mathematic property of the repulsion algorithm.
[0042] In FIGS. 6 and 7 , 2D images of a seismic formation, before and after applying methods of the present invention are illustrated. The images show a set of normal faults that have been identified, possibly around the top of an anticline fold. In FIG. 6 , a seismic section showing horizons offset by a set of normal faults is shown. Faults 602 are involved in faulting reversal, and intersect horizons that are used as geological constraints. The elastic model in the formulation is characterized by a Young's modulus of about 3×10 9 Pa and a Poisson's ratio of 0.25. The formation is partitioned into a number of triangles, and a finite element method is used to solve the minimization problem for a given slip function on the fault trace. As shown in FIG. 7 , the faulting reversal method was applied across 12 faults 602 by requiring that visible horizons be continuous across these faults. The offset of each horizon against a specific fault defines a slip vector. Piecewise linear functions based on these slip vectors were used to approximate the displacement fields on each of the respective faults. Note that several faults 604 were not restored. Note that some faults cut through the section. For those faults with two tips inside the section, the displacement is attenuated to zero at these tips. After applying elastic deformation, the deformed formation as shown in FIG. 7 resulted.
[0043] FIGS. 8-12 , flowcharts illustrate the methods in one embodiment of the present invention. The presently described methods may also be practiced in various other embodiments that omit or rearrange the method steps shown in FIGS. 8-12 . In FIG. 8 , method 800 shows the basic elements of the method, beginning with step 801 . Seismic data regarding a formation are received in step 802 . The seismic data may be in the form of images or numerical data that may be reduced to a structure of a volume of a formation. In one example of step 802 , 3D seismic scan data of a formation containing one or more faults is provided.
[0044] The next method step 804 in FIG. 8 involves defining a physical model based on received data. In FIG. 9 , one example of step 804 beginning with step 900 is shown in further detail. From the seismic data, the location of fault surfaces and location of horizons or other features in the formation is performed in step 902 . Then in step 904 , the volume and surface boundaries of the formation are decomposed, i.e., reduced to finite elements. In step 906 , the boundary integral equation is derived and applied. In step 908 , the equation for the displacement and traction vectors is derived from the boundary integral equation, which completes method 804 at step 910 .
[0045] The method presently described assumes that the fault surface does not change for the purposes of 3D restoration. Since the goal of the present inventive methods is restoration to the un-faulted state, the actual behavior of the fault surface during the fault event is not particularly relevant. The results of embodiments of the present invention indicate that a 3D restoration that is mechanically coherent may be provided under the assumption of a fixed fault surface.
[0046] The next method step 806 in FIG. 8 involves performing a numerical procedure on the physical model. In FIG. 10 , one example of step 806 beginning with step 920 is shown in further detail. In step 921 , the boundary conditions for displacement vectors are provided. This may involve determining a slip restoration vector for a recognizable horizon split by a fault. In step 922 , initial traction values for vertices on the fault surface are assumed. In step 924 , the displacement and traction for each boundary vertex is resolved. From step 924 , the method 806 may branch off to a portion 930 , which represents an iterative solution for displacement and traction vectors on the fault surface. In step 926 , the displacement vectors are checked to see if the space constraint is violated. If the space constraint is violated, then in step 928 new repulsion stresses are estimated. In one case, an incremental or decremental change to the previous repulsion stress values is applied in step 928 . After step 928 , step 924 is repeated, and the cycle given by 930 may continue until the result of step 926 is NO. If the space constraint is not violated by the given displacement and traction values, then step 926 proceeds to step 931 , where the deformation of the entire volume may now be calculated, since all required quantities are known. The method 806 terminates at step 932 .
[0047] The next method step 808 in FIG. 8 involves generating a new unfaulted, i.e., restored, model of the formation based on a numerical procedure. In FIG. 11 , one example of step 808 beginning with step 940 is shown in further detail. In step 942 , the computed deformation from the restoration displacement vectors is applied to the original data. The resulting 3D restored volume is stored in step 944 . In one example, the 3D volume is represented as one or more 2D slices or sections. In step 946 the resulting restored 3D volume may be displayed. In one example, the display involves generating any plane from the 3D volume and displaying this in 2D. In another example of step 946 , the entire volume is displayed in 3D. In on embodiment of step 946 (not shown), a determination may also be made that the restoration was not accurate or deficient in some aspect, such that the method execution returned to step 920 and performed another iteration of method 806 with values correcting for the deficiency, and leaving other values unchanged. Method 808 terminates at step 950 .
[0048] The next method step 810 in FIG. 8 involves the restored results may be stored, displayed, reported or used for further assessments. In FIG. 12 , one example of step 810 beginning with step 960 is shown in further detail. Steps 962 , 064 or 966 represent alternative paths for specifying a data set from the restored data. In step 962 , a computation is executed on the restored data set, for example a scaling function. In step 964 a conditional query is performed to retrieve a portion of the restored data set. In step 966 , a filtering or data reduction algorithm is applied to the restored data set. Note that steps 962 - 964 may be executed in a consecutive manner with omission or repeat of certain steps, and that other methods of specifying or altering the restored data set may be applied. In step 968 , the resulting or retrieved data set may be stored or fetched, respectively. In one example, a query on a relational database is run in step 964 and the resulting query is fetched and stored in step 968 . In step 970 the data set may be displayed in an analogous manner to step 946 . In step 972 , a report or image of the resulting data set may be generated. The report or image may be in 2D or 3D, in an analogous manner as for the display in step 946 . In step 974 an method for assessing the resulting data set may be applied. In one example of step 974 , the assessment is a manual analysis and comparison with other data sets. In another example of step 974 , an algorithm is applied to the resulting data set. Other embodiments of step 974 may involve recognition of exploitable resources in the seismic formation, which were not apparent before the fault restoration.
[0049] One example implementation of a 3D restoration according to method 800 is now described in detail.
[0050] For given restoration slip vectors on fault surfaces, and given traction vectors on other parts of the volume boundaries, the deformation of the volume results in the minimum strain energy among all admissible deformations. An equivalent statement of this formulation is the well-known virtual work principle. This principle states that at equilibrium, the work done by any virtual displacement is zero. From the virtual work principle, the displacement vector at a point i in a volume can be computed from integrals of the displacement and traction vectors over the boundaries. By restriction to the points on the boundaries of the volume, one obtains a boundary integral equation.
[0051] Using Green's functions for virtual displacement and tractions, we may derive the a mathematical formulation from the virtual work principle. For each volume on either side of the fault service, such as sections 304 and 302 , the following boundary integral equation applies:
c u → ( p i ) = ∑ e = 1 E ∑ n = 1 3 t → n e ∫ S e N n ( ξ ) U ( p i , ξ ) ⅆ S ( ξ ) - ∑ e = 1 E ∑ n = 1 3 u → n e ∫ S e N n ( ξ ) T ( p i , ξ ) ⅆ S ( ξ ) ( 1 )
in equation (1) c is a constant; {right arrow over (u)}(p i ) is the displacement vector for point p i in the volume enclosed by surface S (i.e., point p i may be defined by coordinates (x i , y i , z i ) for index i); E is the total number of triangular surface elements indexed by e; n is the vertex index for a given triangular element; {right arrow over (t)} n e and {right arrow over (u)} n e are the traction and displacement vectors, respectively defined at the vertex n of element e; S e represents the surface of element e; ξ represents the points on the surface of element e; N n is a base function associated with vertex n as a function of ξ; U(p i ,ξ) is the kernel function for displacement; and T(p i ,ξ) is the kernel function for traction. After assembling the integrals, one obtains a boundary element equation on the displacement and traction at the vertices of a boundary. The integrals in equation (1) can be evaluated using a standard numerical quadrature. The resulting equation is:
c u → i = ∑ e = 1 E ∑ n = 1 3 t → n e Δ U ni - ∑ e = 1 E ∑ n = 1 3 u → n e Δ T ni ( 2 )
After reassembling, the following equation may be derived.
∑ i , j = 0 N A ij u → j = ∑ i , j = 0 N B ij t → j ( 3 )
Note that in the system of equation (3) there are N equations on N displacement vectors and N traction vectors on the surface of a volume section. Furthermore, the displacement and traction functions on the small elements may be approximated with simple functions, such as linear functions. These simple functions are parameterized with the displacement and traction value at the vertices of the element. In equation (3), A ij is a matrix reassembled from ΔT ni in equation (2), while B ij is a matrix reassembled from ΔU ni of equation (2). In such a way, the boundary integrals on an element become a linear combination of the displacement or traction value at the vertices. If a boundary condition is given, the displacement or traction vector at each vertex of the boundary is resolved. If the number of known displacement or traction vectors equals to N, the problem is well defined, and the unknown displacement at each vertex can be obtained by solving equation (3).
[0052] By applying given slip vectors on the contact surface (such as surfaces 402 and 502 ) and some traction condition to other parts of the boundary (such as the remaining surfaces of sections 302 and 304 ), equation (3) can be solved for displacement and traction vectors at each vertex on the boundary. Once the displacement and traction at each vertex on the boundary is known, the deformation at any given interior point of the part can be then obtained by equation (2). In effect, this procedure removes the faulting and restores the volume to a pre-fault state.
[0053] The next step in the fault restoration is resolving the slip vectors on the fault surface. When a horizon is offset by a fault, the discontinuity of the horizon can be used for defining the restoration slip vectors (see FIG. 2 , vectors 210 , 212 ). In this way restoration slip vectors can be defined on the intersection of the horizon and the fault. The intersection defines a polyline on the faulting surface. Note that the displacement at the other points on the fault surface cannot be defined by the discontinuity of the horizon. The extrapolation of these same slip vectors to other vertices on the fault surface would erroneously result in penetration of the volume unless a correction is made.
[0054] In a fault restoration problem, input displacement vectors may be given for the contact boundary of one volume section, for example surface 402 for section 304 , or surface 502 for section 302 . In various example case, given displacement vectors may be supplied manually, i.e., by a user, or automatically by an analytical method, from a calibrated data set, such as a digital image, of the faulted seismic formation. In one embodiment, the input displacement vectors may result from an automated analysis method operating on a 3D data set representing a faulted formation. In one embodiment, an image analysis routine operating on a 2D image may vectorize the formations on either side of a fault line, detect a horizon discontinuity from the vectorized image, and automatically return a restoration slip vector (or at least the 2D planar component thereof) for each detected discontinuity; such a process may be repeated with several images of the formation, representing different sectional views, to assemble 3D representation of the input displacement vectors. In one manual implementation, the input displacement vectors may be manually chosen such that a feature on the contact surface of one section, such as the intersection of a horizon surface with the fault surface, will meet the commensurate horizon/fault intersection of the section on the other side of the fault surface. This kind of displacement vectors are generally referred to as slip vectors, a term common in structural geology. From the point view of structure, restoration, the main quandary is the removal of the discontinuity of the horizon due to the faulting. The elasticity model can compensate for other factors to produce a deformed volume characterized by minimum seismic distortion. The specification of restoration vectors at each vertex on the fault surface is not required, the space constraint provides the means to resolve the remaining quantities.
[0055] Note that the input slip vectors are only given at the locations of a recognizable feature on the contact surface, i.e. an intersection of a horizon with the fault surface. These locations normally follow a polyline (a line comprising multiple line segments) on the contact surface, such as the case of horizon-fault intersection. In the small element model, these locations correspond to the vertex of an element at the location. The orientation of a slip vector is also so constrained that no gap or overlay would be created after the reversal, while the magnitude of the slip vector along the horizon remains constant as long as the fault extends through the entire volume section. If a fault only extends partially through a volume section, the slip vector may be tapered to zero at the tips of the fault.
[0056] The displacement or traction vectors at other locations, i.e., vertices, on the contact surface may not generally be known. However, all vertices on the contact surface must additionally satisfy the space constraint, that is, they may not overlap, i.e., cross over, the fault surface. A restricting condition is applied that the fault blocks must not penetrate each other after the restoration. The boundary condition for those points is not an equation but an inequality. To solve the problem of this type, we use the repulsion scheme proposed by Wei and De Bremaecker (see Wei, K. and De Bremaecker, J.-Cl., Fracture Growth Under Compression, Journal of Geophysical Research, 99, 13781-13790, 1994). The basic idea of this scheme is that under an appropriate repulsion or traction stress applied normal to a surface element, the fault sections do not penetrate each other. However, the exact values of the repulsions are not known in advance, but rather, may be iteratively determined, as they will converge on the solution to the inequality. Initially an estimated value of the repulsions or tractions to those points under an inequality constraint is applied. In one example, all normal tractions stresses are set to zero on the first iteration. If a penetration is found at a vertex, the repulsion stress at the corresponding element is incremented. If a gap opening is found at a vertex, the repulsion stress is decremented, in other words, attraction stress is incremented. This scheme is iterative and does converge after several iterations. Thus, with a sufficient traction applied to the fault surface vertices, the space constraint can be iteratively satisfied. In one case, satisfaction of the space constraint requires that no vertex violates the space constraint by an amount greater than a minimum displacement from the fault surface. In one example, a minimum violation of the space constraint is 10 −2 m.
[0057] FIG. 13 is a block diagram representing one set of embodiments of a computer system 1082 that may take the role of the server computer or the client computer as variously described herein.
[0058] The computer system 1082 may include at least one central processing unit CPU 1160 (i.e., processor) that is coupled to a host bus 1162 . The CPU 1160 may be any of various types, including, but not limited to, an x86 processor, a PowerPC processor, a CPU from the SPARC family of RISC processors, as well as others. A memory medium, typically including semiconductor RAM, and referred to herein as main memory 1166 , may be coupled to the host bus 1162 by means of memory controller 1164 . The main memory 1166 may store programs operable to implement any or all or any subset of the various methods embodiments described herein. The main memory may also store operating system software, as well as other software for operation of the computer system.
[0059] The host bus 1162 may couple to an expansion or input/output bus 1170 through a bus controller 1168 or bus bridge logic. The expansion bus 1170 may include slots for various devices such as a video card 1180 , a hard drive 1182 , storage devices 1190 (such as a CD-ROM drive, a tape drive, a floppy drive, etc.) and a network interface 1122 . The video card 1180 may couple to a display device such as a monitor, a projector, or a head mounted display. The network interface 1122 (e.g., an Ethernet device) may be used to communicate with other computers through a network. The computer system 1082 may also include I/O devices 1192 such as a mouse, keyboard, speakers.
[0060] Embodiments of computer system 1082 targeted for use as a server computer may be more richly endowed with processor capacity (e.g., having multiple processors), memory capacity and network access bandwidth than embodiments targeted for use as a client computer. The client computer may include the mouse, keyboard, speakers and video card (or graphics accelerator), whereas a server computer does not necessarily include these items.
[0061] Any method embodiment (or portion thereof) described herein may be implemented in terms of program instructions. The program instructions may be stored on any of various kinds of computer readable memory media. The program instructions are readable and executable (by a computer or set of computers) to implement the method embodiment (or portion thereof).
[0062] Although the embodiments above have been described in considerable detail, numerous variations and modifications will become apparent to those skilled in the art once the above disclosure is fully appreciated. It is intended that the following claims be interpreted to embrace all such variations and modifications. | Solutions to the problem of reversing seismic fault movements are formulated using a model based on elasticity theory, and using finite element and boundary element methods for generating a solution. The solution involves defining slip vectors from known formations in the fault and applying a space constraint restriction to traction values on the fault surface. The method may be applied in either 2D or 3D applications. The method is computationally fast enough to allow interactive fault reversal, and permits experimentation with various unfaulting scenarios so that a geologically acceptable solution is provided. | 6 |
FIELD OF THE INVENTION
[0001] The present invention generally relates to remote control units and more particularly to remote control units for use while wearing gloves.
BACKGROUND
[0002] Over the past several decades there has been widespread adoption by consumers of various types of audio/video players. Devices such as compact disc (CD) players, radio receivers, mp3 players, digital media players, and other similar audio/video players have become commonplace in many households. Many of these audio/video players are designed to be operable by built-in control panels, which allow users to control different functions such as adjusting the sound volume, stopping a track, rewinding a track, fast forwarding a track, etc. However, the built-in control panel is inconvenient when a audio/video player is not conveniently accessible by the user. In view of this disadvantage, remote control units have been extensively developed. Using a remote control unit, a user can perform a variety of operations such as switching to a different track on a DVD playing in a DVD player, or changing the volume of a media player, even when the player is not conveniently accessible.
[0003] In the past, when a person wearing gloves or mittens wished to use a remote control unit while wearing the glove, it has been necessary to remove the glove completely to use the remote control or other electronic device requiring manual dexterity. Accordingly, there is a need for an improved remote control and glove system which allows easy operability of the remote control or other electronic device without having to remove the glove. This problem is particularly relevant where the conditions are cold, wet or otherwise unpleasant and it would be uncomfortable and unwieldy to remove the glove or mitten.
SUMMARY
[0004] Methods and systems consistent with the present invention include a wired or wireless remote control unit engineered to be coupled to, affixed to, or fit over a gloved hand, or incorporated within a glove or mitten and having large buttons capable of being pressed through or within gloved or covered finger tips. Accordingly, a user is able operate a wired or wireless remote while wearing gloves or mittens or other hand covering and keeping their hands warm.
[0005] In one embodiment consistent with the present invention, remote control unit is affixed to the palm of the glove by a strap, belt, button, velcro, glue, snap, zipper or some other coupling device or method. In another embodiment consistent with the present invention, the remote control unit is affixed to a side posterior to the palm by a strap, belt, button, velcro, glue, snap, zipper or some other coupling device or method. In yet another embodiment consistent with the present invention, the remote control unit is integrated in the glove. A control pad for the remote control unit is enmeshed in the fabric of the glove. In one embodiment consistent with the invention, the control pad is enmeshed in the palm of the glove. In another embodiment of the invention, control pad is enmeshed in the side of the glove posterior to the palm.
[0006] In still another embodiment consistent with the present invention where the remote control unit is integrated with the glove, buttons for operating the remote control unit are located at the tips of the fingers and thumbs on the anterior or palm side of the glove. In another embodiment of the invention, the buttons for operating the remote control unit are located at the tips of the fingers and thumbs on the posterior side of the glove.
[0007] The remote control may be wired or wireless. Wireless transmission mediums include radio frequency, infrared, and any other equivalent wireless transmission medium.
[0008] Other systems, methods, features, and advantages consistent with the present invention will become apparent to one with skill in the art upon examination of the following figures and detailed description. It is intended that such additional systems, methods, features, and advantages be included within this description and be within the scope of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate an implementation of the invention and, together with the description, serve to explain advantages and principles consistent with the invention. In the drawings,
[0010] FIG. 1 illustrates a glove remote control system consistent with a first embodiment of the present invention
[0011] FIG. 2 illustrates a glove remote control system consistent with a second embodiment of the present invention;
[0012] FIG. 3 illustrates a glove remote control system consistent with a third embodiment of the present invention;
[0013] FIG. 4 illustrates a glove remote control system consistent with a fourth embodiment of the present invention;
[0014] FIG. 5 illustrates a glove remote control system consistent with a fifth embodiment of the present invention;
[0015] FIG. 6 illustrates a glove remote control system consistent with a sixth embodiment of the present invention;
[0016] FIG. 7 illustrates a glove remote control system consistent with a seventh embodiment of the present invention; and
[0017] FIG. 8 illustrates a glove remote control system consistent with an eighth embodiment of the present invention.
DETAILED DESCRIPTION
[0018] As used herein, the term “glove” is meant to include any form of hand covering, including, but not limited to, gloves, mittens, hand warmers, pockets, mitts, bandages, and wraps.
[0019] In one embodiment consistent with the present invention, a glove remote control unit is attached to a glove as illustrated in FIG. 1 . The glove remote control unit comprises a control casing, circuitry for generating signals to operate a media device such as an audio player, enlarged buttons for operation of the remote control while wearing gloves, and an adjustable strap or flexible band extending at both ends of the control casing in fully or semi-closed loop to be worn over a gloved hand or any place the user desires. Operation of this device may include transmitting or receiving commands, transmitting or receiving information, transmitting or receiving audio signals, or transmitting or receiving video signals for display. Using the glove remote control unit, a user may operate a media player through a received in the media player with removing the user's gloves, thus keeping the user's hands warm in frigid weather. The glove remote control unit also allows the user to easily carry the (receiver) unit along, storage and preventing from falling on the ground in use.
[0020] Methods and systems consistent with the present invention utilizes a belt or strap similar to that of a wrist watch or armband. The belt or strap may be an adjustable or flexible band extending at both ends of the control casing in fully or semi-closed loop to be worn over a gloved hand or any place the user desires. This strap or belt may be a chain, belt, expansion or foldable structure, a retractable mechanism for pull and extension effects, or a buckle and shackle with multiple fixing holes.
[0021] The glove remote control unit may transmit information to and receive information from the controlled device, such as a media player, by either a wired or wireless medium. The remote control unit casing and buttons can be in any size or dimension whether in a circular, square or any irregular shape desired such as in the three versions provided. The remote control casing can be controlled by pressing its large buttons through a gloved hand and is not limited to a ball, roller, or joystick integrated into the control device. Functions may include the operation of commands and data transmission or reception and transmission of remote controlled message by means of infrared or radiation frequency transmissions. The controlled device may also be an electronic home appliances, toys, education, and other domestic systems or industries.
[0022] The glove remote control unit may control audio or video functions with a 5-button infrared transmitter functions: play/pause, next track/fast forward, previous track/rewind, volume up, and volume down. The glove remote control unit may include other buttons such as a hold button. The said transmitter unit sends control signals to the receiver unit, which may be an MP3 player, cell phone, or any other consumer or industrial electrical product.
[0023] In another embodiment consistent with the present invention, the glove remote control unit is located on the side of the posterior to the palm, as illustrated in FIG. 2 .
[0024] The controls of the glove remote control unit may also be embedded or integrated inside, or on any surface of a glove that includes on top, inside the palm, or on the finger tips. This type of control device glove can be in any size or dimension whether in a circular, square or any irregular shape desired.
[0025] In yet another embodiment consistent with the present invention, the remote control unit is integrated in the glove. A control pad for the remote control unit is enmeshed in the fabric of the glove. In one embodiment consistent with the invention, the control pad is enmeshed in the palm of the glove, as illustrated in FIG. 3 . In another embodiment of the invention, control pad is enmeshed in the side of the glove posterior to the palm, as illustrated in FIG. 4 .
[0026] In still another embodiment consistent with the present invention where the remote control unit is integrated with the glove, buttons for operating the remote control unit are located at the tips of the fingers and thumbs on the anterior or palm side of the glove, as illustrated in FIG. 5 . In another embodiment of the invention, the buttons for operating the remote control unit are located at the tips of the fingers and thumbs on the posterior side of the glove, as illustrated in FIG. 6 .
[0027] FIG. 7 illustrates an interior view of the gloves illustrated in FIG. 5 or 6 . Buttons 10 , 12 , 14 , 16 , and 18 are operatively connected to control box 30 by wires 20 , 22 , 24 , 26 , and 28 , respectively. Wires 20 , 22 , 24 , 26 , and 28 are flexible and may be wire of copper or any other conductive material. Alternatively, wires 20 , 22 , 24 , 26 , and 28 may be fiber optic wires. Control box 30 processes signals received from the buttons 10 , 12 , 14 , 16 , and 18 , and transmits the corresponding command to a receiver (not shown). Control box 30 may include a power supply and transmission antenna. Control box 30 may further be connected to the receive by a wire (not shown). The wires 20 , 22 , 24 , 26 , and 28 , buttons 10 , 12 , 14 , 16 , and 18 , and control box 30 may be enmeshed in the fabric of glove 50 .
[0028] FIG. 8 illustrates yet another embodiment consistent with the present invention that utilizes a belt or strap around the fingers of the glove. The belt or strap may be an adjustable or flexible band extending at both ends of the control casing in fully or semi-closed loop to be worn over one, two, three, or four of the glove fingers. This strap or belt may be a chain, belt, expansion or foldable structure, a retractable mechanism for pull and extension effects, or a buckle and shackle with multiple fixing holes.
[0029] In one embodiment consistent with the present invention, the glove remote control unit is located on the side of the palm of the glove. In another embodiment consistent with the present invention, the glove remote control unit is located on the side of the posterior to the palm.
[0030] While there has been illustrated and described embodiments consistent with the present invention, it will be understood by those skilled in the art that various changes and modifications may be made and equivalents may be substituted for elements thereof without departing from the true scope of the invention. | Methods and systems consistent with the present invention provide a wired or wireless remote control unit engineered to fit over a gloved hand and having large buttons capable of being pressed through gloved finger tips. Accordingly, a user is able operate a wired or wireless remote while wearing gloves and keeping their hands warm. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention pertains to the art of cooking appliances and, more particularly, to a cooking appliance having an automated calibration system that maintains operational parameters of the cooking appliance within optimal limits.
2. Discussion of the Prior Art
In general, it is known that electric cooking appliances are affected by variations in supply voltage. That is, as electric cooking appliances utilize electric heating elements that output power, variations in supply voltage will result in variations in power output. Given that P=V 2 /R, a ten-volt variation in voltage will result in a significantly greater variation in power output by the electric heating element. In cooking appliances, variations in supply voltage can alter the time it takes to achieve a desired cooking temperature. In addition, variations in supply voltages make maintaining a desired temperature more difficult. When the cooking appliance is not operating under optimal conditions, pre-established operating parameters will not be able to achieve or maintain desired output conditions. Food could end up being either over or under-cooked. For example, when operating an electric cooking appliance that is programmed with a cook time, the established cook time may not be sufficient to properly cook the food if significant voltage variations occur during the cooking operation. Based thereon, it is considered important to periodically calibrate or adjust the operational parameters to correspond to the amount of heat produced by the electric elements.
In recognition of this problem, the prior art contains several examples of systems designed to compensate for variations in supply voltage. Some of these systems monitor the supply voltage and, based on the monitored voltage, alter an overall cook time for a cooking operation. Other systems monitor the supply voltage, then compare the supply voltage with a known, nominal value. The difference, if any, between the supply voltage and the known value is used to set particular cycle times of one or more electric heating elements. In still other systems, a controller monitors power and voltage values. These values are compared to stored data to determine particular cycle times of a heating element. While each of the above systems is generally effective, they fail to account for other factors which can influence power output by an electric heating element.
In addition to supply voltage variations, the resistance of an electric heating element will change over time. A change in resistance of the element will also have an effect on the amount of power output by the element. Also, the degradation of insulation around the cooking appliance and door sealing characteristics will affect the amount of heat needed to maintain a particular temperature within an appliance. None of the examples proposed in the prior art address these issues. In addition, the prior art systems are not considered to be readily adaptable to new oven designs.
Based on the above, there still exists a need in the art for an oven calibration system that will effectively maintain an oven temperature regardless of variations in supply voltage. More specifically, there exists a need for an oven calibration system that will also account for changes in oven performance resulting from ordinary wear of the cooking appliance in order to remain within optimal operating conditions.
SUMMARY OF THE INVENTION
The present invention is directed to a cooking appliance including an oven cavity, an electric heating element, a control element for selecting a desired oven cavity temperature (T P ), a timer, a control unit, and an automated calibration system, wherein the calibration system regulates or adjusts established operational parameters of the cooking appliance based upon a time/temperature relationship in order to ensure optimal cooking operations. Preferably, the timer determines an amount of time required to achieve the oven cavity temperature (T P ) during a no load condition. That is, the timer measures the amount of time it takes to reach a selected temperature (T P ) when there is no food or other items in the oven cavity that might otherwise absorb a portion of the heat. In accordance with a preferred embodiment of the invention, the calibration system is operated during a self-clean mode of operation as no food will be present in the oven cavity. During the self-clean mode, the electric heating element is operated at maximum capacity until a desired temperature (T SC ) is achieved. In this manner, an accurate measurement, corresponding to power output by the heating element, can be obtained. Once obtained, the calibration system can adjust the established operational parameters, such as offset temperatures, hysterisis temperatures and cooking times, in order to account for variations in heat delivered to and retained by the oven cavity.
Additional objects, features and advantages of the present invention will become more readily apparent from the following detailed description of a preferred embodiment when taken in conjunction with the drawings wherein like reference numerals refer to corresponding parts in the several views.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a perspective view of a wall oven including an automated calibration system constructed in accordance with the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
With initial reference to FIG. 1 , a cooking appliance constructed in accordance with the present invention is generally indicated at 2 . Cooking appliance 2 , as depicted, constitutes a double wall oven. However, it should be understood that the present invention is not limited to this model type and can be incorporated into various types of oven configurations, e.g., cabinet mounted ovens, as well as both slide-in and free-standing ranges. In any event, in the embodiment shown, cooking appliance 2 constitutes a dual oven wall unit including an upper oven 4 having upper oven cavity 6 and a lower oven 8 having a lower oven cavity 10 . Cooking appliance 2 includes an outer frame 12 for, at least, partially supporting both upper and lower oven cavities 6 and 10 .
In a manner known in the art, a door assembly 14 is pivotally mounted to outer frame 12 and, when in a closed position, extends across oven cavity 6 . As shown, door assembly 14 includes a handle 15 at an upper portion 16 thereof. Door assembly 14 is adapted to pivot at a lower portion 18 to enable selective access to within oven cavity 6 . In a manner also known in the art, door 14 is provided with a transparent zone or window 22 for viewing the contents of oven cavity 6 while door 14 is closed. A corresponding door assembly 24 , including a handle 25 and a transparent zone or window 26 , is provided to selectively access lower oven cavity 10 .
As best seen in FIG. 1 , oven cavity 6 is defined by a bottom wall 27 , an upper wall 28 , opposing side walls 30 and 31 and a rear wall 33 . In a manner known in the art, side walls 30 and 31 are provided with a plurality of vertically spaced side rails indicated generally at 34 for supported oven racks and the like in oven cavity 6 . In the preferred embodiment shown, bottom wall 27 is constituted by a flat, smooth surface designed to enhance the cleanability of oven cavity 6 . Arranged about bottom wall 27 of oven cavity 6 is a bake element 40 . Also, a top broiler element 42 is arranged along upper wall 28 of oven cavity 6 . Top broiler element 42 is provided to enable a consumer to perform a grilling process in upper oven 4 and to aid in pyrolytic heating during a self-clean operation. More specifically, both bake element 40 and top broiler element 42 are constituted by sheathed electric resistive heating elements.
Based on the above, in the preferred embodiment depicted, cooking appliance 2 actually constitutes an electric, dual wall oven. However, it is to be understood that cooking appliance 2 could also incorporate various other heat sources, such as a microwave generator, to supplement the operation of bake element 40 and top broiler element 42 . In any case, both oven cavities 6 and 10 preferably employ both radiant and convection heating techniques for cooking food items therein. To this end, rear wall 33 is shown to include a convection fan or blower 44 . Although the exact position and construction of fan 44 can readily vary in accordance with the invention, fan 44 draws in air at a central intake zone (not separately labeled) and directs the air into oven cavity 6 in a radial outward direction. Also, as clearly shown in this figure, a convection heating element 46 , which preferably takes the general form of a ring, extends circumferentially about fan 44 in order to heat the radially expelled air flow. At this point, it should be noted that a fan cover, which has not been shown for the sake of clarity of the drawings, extends about fan 44 and convection heating element 46 , preferably with the cover having an associated central inlet and a plurality of outer radial outlet openings.
As further shown in FIG. 1 , cooking appliance 2 includes an upper control panel 50 having a plurality of control elements. In accordance with one embodiment, the control elements are constituted by first and second sets of oven control buttons 52 and 53 , as well as a numeric pad 54 . Control panel 50 is adapted to be used to select desired cooking operations and, as will be discussed more fully below, input initial operating conditions for cooking appliance 2 . More specifically, the first and second sets of control buttons 52 and 53 , in combination with numeric pad 54 and a display 62 , enable a user to establish particular cooking operations, e.g., a bake mode, a broil mode, a convection cooking mode and a self-clean mode for upper and lower ovens 4 and 8 respectively and, if so equipped, selection from a menu of pre-programmed cooking operations. This arrangement has been described in co-pending application Ser. No. 10/410,155 filed Apr. 10, 2003, which is entitled “Menu Driven Control System for a Cooking Appliance,” assigned to the assignee of the present application and incorporated herein by reference.
In accordance with a preferred form of the present invention, a control unit or CPU 72 , having a non-volatile memory unit 74 , is provided to control cooking appliance 2 . As will be discussed more fully below, CPU 72 operates or controls cooking appliance 2 based on established operating parameters stored in memory 74 . That is, in order to achieve and maintain a desired temperature, various factory set operating parameters, such as offset temperatures, hysterisis temperatures and cook times, are stored in memory 74 . Upon selection of a desired cooking temperature (T P ) or a pre-programmed cooking operation, cooking appliance 2 will enter a pre-heat mode during which CPU 72 will activate one or more of the electric heating element(s), i.e., bake element 40 , broil element 42 and/or convection element 46 , to begin raising the temperature in oven cavity 6 to the desired temperature (T P ). Once the desired temperature (T P ) is reached, cooking appliance 2 will enter a cooking mode during which time CPU 72 will begin to cycle the operation of the heating element(s) 40 , 42 , 46 to maintain the temperature (T P ).
Actually, in order to maintain the desired temperature (T P ) in oven cavity 6 , CPU 72 activates the electric heating element(s) 40 , 42 , 46 until reaching the desired temperature (T P ) plus an upper offset temperature value (T 1 ). Once the upper offset temperature value is reached, the heating element(s) 40 , 42 , 46 is deactivated. The temperature in oven cavity 6 is then allowed to fall, past the desired temperature (T P ), until reaching a second or lower offset temperature value (T 2 ), at which time the electric heating element(s) 40 , 42 , 46 is reactivated. In accordance with the invention, the upper and lower offset temperature values (T 1 and T 2 ) may be identical or may differ depending on various operating conditions, such as supply voltage, heating element power rating, oven cavity size, and other various dynamics of cooking appliance 2 . In any event, the difference between the upper offset temperature (T 1 ) and the lower offset temperature (T 2 ) define a hysterisis temperature (T H ). CPU 72 continues to periodically cycle operation of the electric heating element(s) 40 , 42 , 46 to maintain the desired temperature (T P ), which is actually an average temperature value defined by a hysterisis temperature loop, until the cooking operation is terminated, either through user input or automatically by CPU 72 .
The established operating parameters are actually values based upon ideal operating conditions. That is, the offset temperatures (T 1 and T 2 ), hysterisis temperature (T H ) and cook times are based upon operating the heating element(s) 40 , 42 , 46 at a defined supply voltage in order to achieve a rated power output. Unfortunately, it is not always possible to operate under ideal conditions. Supply voltages vary, heating elements degrade over time and a variety of other factors all contribute to cooking appliance 2 operating at less than ideal conditions. Therefore, in order to operate more efficiently, it becomes necessary to periodically calibrate cooking appliance 2 . Toward that end, cooking appliance 2 includes an automated calibration system 84 which functions to periodically adjust established operational parameters of cooking appliance 2 .
In accordance with one preferred form of the invention, after a user selects a particular cooking operation and a desired temperature value (T P ) for the particular cooking operation, CPU 72 activates at least one of electric heating elements 40 , 42 and 46 to elevate a temperature of oven cavity 6 to correspond to the desired temperature value (T P ). At the same time, CPU 72 initiates a timer 88 that measures a time period by incrementing a counter indicative of a time value. CPU 72 also begins to receive signals from a temperature sensor 90 that is positioned to sense the temperature in oven cavity 6 . Once CPU 72 receives a signal from sensor 90 that oven cavity 6 has reached the desired temperature (T P ), timer 88 is stopped, while the heating element(s) 40 , 42 and 46 continues to operate until oven cavity 6 reaches the upper offset temperature. At this point, CPU 72 passes a signal representative of the desired temperature (T P ) and the time value in timer 88 to calibration system 84 . As an alternative to measuring an elapsed period of time, timer 88 could also countdown from a predetermined value. In this case, any difference between the elapsed time and the predetermined value at the moment T P is reached is sent to calibration system 84 .
The desired temperature value (T P ) and the time value are input into a control algorithm in calibration system 84 . The control algorithm then calculates a power value corresponding to the power necessary to achieve the desired temperature (T P ) in the time period measured by timer 84 . Once the power value is determined, calibration system 84 will, if necessary, make adjustments to the established operational parameters of cooking appliance 2 . That is, if the calculated power value indicates that cooking appliance 2 is not operating within an optimal range, calibration system 84 will adjust the established operating parameters, e.g., adjust the upper and lower offset temperatures (T 1 and T 2 ), the hysterisis temperature (TH) or the cook time, in order to bring the operation of cooking appliance 2 within the optimal range. More specifically, if it is found to take longer to reach T 1 , the value of T 2 is increased to prevent the oven from losing too much heat. Likewise, if the time to reach T 1 decreases, T 2 can be decreased. The adjusted or calibrated operational parameters then replace the established values in memory 74 for use in subsequent cooking operations. In this manner, food placed within oven cavity 6 will be cooked properly, that is, over and under-cooked conditions can be avoided. Moreover, if the user selects a pre-established cooking operation that uses a predetermined cook time, calibration system 84 will ensure that the cooking operation will be completed properly and on time.
The ideal time to initiate calibration system 84 is during periods when oven cavity 6 is empty, i.e., when there is no load present that would otherwise absorb heat output by the heating element(s). Therefore, in accordance with the most preferred form of the present invention, calibration system 84 is automatically activated during the self-clean mode of operation. In one preferred form of the invention, once a user selects the self-clean mode, CPU 72 actives heating elements 40 , 42 and 46 to elevate the temperature of oven cavity 6 to correspond to a self-clean temperature value (T SC ). In a manner similar to that described above, once heating elements 40 , 42 , and 46 are activated, timer 88 is initiated. CPU 72 continues to poll sensor 90 at least until a signal, representative of the self-clean temperature value (T SC ), is returned. Once oven cavity 6 has reached the self-clean temperature (T SC ), as evidenced by the return signal from sensor 90 , timer 88 is stopped. At this point, the time value is passed to calibration system 84 . Implementing the control algorithm, calibration system 84 determines if adjustments to the established operational parameters of cooking appliance 2 are required to compensate for variations in performance. If so, the adjusted or calibrated operational parameters are then stored in memory 74 so that future cooking operations are performed in the most efficient manner.
With this arrangement, the established operating parameters can be periodically updated to account for variations in supply voltage, changes over time in the resistance of the heating element(s), and other factors that would otherwise contribute to inefficient cooking operations. Furthermore, the calibration system of the present invention is forward looking in that a control system is provided that is adaptable to a wide array of oven cavity geometries, as well as future cooking appliance designs. Although described with reference to a preferred embodiment of the present invention, it should be readily apparent to one of ordinary skill in the art that various changes and/or modifications can be made to the invention without departing from the spirit thereof. For instance, the invention could also be employed with other types of electric cooking appliances, such as ranges, slide-in units and the like. In addition, the calibration system could determine the power value by using a sensed temperature at a prescribed time period. Furthermore, while the timer is described as being stopped once the desired temperature is reached, the timer could continue to operate until the upper offset temperature is reached. In general, the invention is only intended to be limited by the scope of the following claims. | A cooking appliance includes an oven cavity, an electric heating element, a control element for selecting an oven cavity temperature, a timer and a calibration system for regulating operational parameters of the cooking appliance. The calibration system adjusts operational parameters of the cooking appliance based upon an amount of time required to achieve the selected oven cavity temperature. Preferably, the timer measures the amount of time needed to achieve the oven cavity temperature during a no load condition in order to set a baseline. Once the time is determined, the calibration system adjusts offset temperatures, hysterisis temperatures and/or cooking times to account for variations in power delivered to the oven cavity. | 5 |
Research relating to the present application supported by Contract No. 58-114-1003 from the United States Department of Agriculture.
BACKGROUND OF THE INVENTION
The present invention relates to techniques for detection and identification of biological contaminants in vegetable foodstuffs. More particularly, the present invention involves the detection of insects or insect parts in whole or milled grain.
The detection of insects in stored grain and the quantitation of insect parts present in milled grain products represents a serious and continuing problem for the cereal industry. Present methods of detection primarily involve visual inspection [usually microscopic] (1, 2) and x-ray analysis (3) which require trained personnel and are time-consuming, difficult to standardize and expensive.
A variety of approaches have been used in the past to attempt development of efficient assay procedures, but none of these has proven particularly satisfactory for routine testing. These methods have included the use of nuclear magnetic resonance (4, 5, 6), sound amplification (7), infrared spectrometry (8), and chemical techniques (9). These techniques have tended to be too expensive, technically difficult and also difficult to quantify and identify the specific infestation detected. For example, sound amplification techniques (10-12) show promise for the detection of live insects in grain but provide little quantitative analysis, and are unable to detect eggs, dead insects or insect part contamination. The preferred characteristics of assays for insect contamination are as follows: it should be highly specific, be very sensitive, rapid, and inexpensive. Moreover, it ideally should be employable by persons having minimal training, particularly in non-laboratory settings, e.g., at grain elevator and mill sites.
The present invention involves approaches to the detection of insect contamination of foodstuffs such as grain, beans (e.g., coffee), spices or even viable crops (e.g., corn, etc.). These approaches involve the detection or discrimination of biological substances specific to insects and usually absent in pure foodstuffs. One such approach is an assay for the insect exoskeleton material, chitin. This test is particularly suited to the detection of live or dead specimens of the adult stages of insects and for insect parts. Another type of assay uses an immunological approach for the detection and quantitation of an insect-specific protein such as the insect muscle protein, myosin or components thereof, for example. This type of test is well suited for detecting all stages of insect development from egg to adult, whether live or dead. It should also provide an assay system that correlates well to the current insect fragment assay and whole insect analysis (eggs to adults).
Chitin is the major structural material of insect exoskeletons. This material is a beta-[1-4]-homopolymer of N-acetylglucosamine, as shown in FIG. 1. Chitin is not found in higher plants. Because of the relatively large amounts of chitin associated with the pupal and adult stages of insects, sensitive biochemical tests for chitin should provide a good means of assaying for the presence of both live and dead insect remains in plant material. Chitin may also be found in certain molds and fungi which could be an important consideration in some circumstances.
Very sensitive and rapid procedures are available for assaying for chitin. Such tests can be modified for successful determination of grain or grain product insect infestation. The most sensitive test procedures for chitin involve hydrolysis of the chitin to N-acetylglucosamine and subsequent assay for the latter compound. Several chemical degradation procedures for chitin hydrolysis have been tested and several N-acetylglucosamine tests evaluated for their suitability for grain assays. One sensitive and reliable assay technique described herein uses an alkaline hydrolysis procedure and has a current detection limit of approximately 1×10 -9 moles of N-acetylglucosamine (NAG). The average grain weevil contains approximately 1.12×10 -6 moles of NAG, which is 1000 times more NAG than is needed for a positive test. The major potential disadvantage of this assay is that it is rather lengthy and requires the use of harsh chemicals. It is clear that the procedures described herein offer a very sensitive means for grain analysis. The further adaptation of chitin assays for low cost and rapid analysis is an object of the present invention.
Immunological assays have found widespread use in clinical diagnostic settings (13), and are also becoming available for in home use, particularly for the early detection of pregnancy (14). The vast potential of these procedures for non-medical purposes has been the subject of increasing study over the last few years. Nowhere is this more evident than in the explosion of commercial uses being developed for the enzyme linked immunosorbent assays (ELISA), which are rapidly becoming standard procedure in a variety of settings (15).
In order to develop an optimal immunological assay for an insect contamination of foodstuffs, antibodies are required which are directed against an insect-specific antigen, preferably protein, likely to be present in any life stage of the contaminating insect or in insect remains. Necessarily, the antisera should not cross-react with any plant material present. For an immunoassay with broad insect-specificity, it would also be preferable to use as an antigen, a protein that is very slowly evolving. Antibodies directed against such an insect-specific protein of one species would cross-react with the same protein in a wide variety of insect species. One such protein is the insect muscle protein myosin. Myosin and components thereof are ubiquitous in insects. Myosin is present in large quantities in adult insect tissue, and is also present in appreciable quantities in other life stages. Finally, myosin is a very slowly evolving protein (16). To develop an immunoassay specific for a particular species of insect contamination, antibodies having a unique species-specificity could be prepared and used. For example, polyclonal or monoclonal antibody could be developed which is directed toward an antigen specifically characterizing a single insect species. Alternatively, polyclonal antibodies, monoclonal antibodies or mixtures thereof could be developed which recognize an epitope of an insect antigen which is common to several or all insect species of interest. Such a broadly specific monoclonal antibody could also serve in reproducible insect assays. Monoclonal antibodies provide a dependable source of identical antibodies.
SUMMARY OF THE INVENTION
The present invention involves methods for determining the estimated degree of insect contamination in a foodstuff such as whole or milled grain, for example. One of these methods involves a sensitive assay for insect-specific biological molecules. For example, assaying chitin content in a sample of said foodstuff may be utilized as a measure of insect presence. Chitin may be assayed directly or indirectly. After an assay of chitin content, the estimated degree of insect contamination in said foodstuff may be calculated from said chitin content.
The insects at all life stages or parts thereof contaminating a foodstuff include, for example: Sitophilus zeamais; Sitophilus granarius; Sitophilus oryzae; Trogoderma variabile; Trogoderma glabrum; Tribolium castaneum: Tribolium confusem; Oryzaephilus mercator; Oryzaephilus surinamensis: Rhyzopertha dominica: Prostephanus truncatus: Lasioderma serricorne: Stegobium paniceum: Callosobruchus maculatus; Attagenus mecatoma; Alphitobius diaperinus; and Plodia interpunctella.
A preferred method of chitin analysis according to the present invention involves the hydrolysis of chitin in foodstuffs such as grain, for example, to N-acetylglucosamine. The N-acetylglucosamine may then be analyzed in a manner both accurate and convenient. The N-acetylglucosamine assay is preferably colorimetric but might be enzymatic. A sample of said foodstuff is initially subjected to conditions sufficient to hydrolyze chitin contained therein to N-acetylglucosamine. The sample of said foodstuff may be subjected to conditions sufficient to chemically or enzymatically hydrolyze any chitin contained therein to N-acetylglucosamine. Chemical chitin hydrolysis may be by acid or alkali, for example. Enzymatic hydrolysis of chitin by a mixture comprising chitinase and chitobiase is a preferred method of obtaining N-acetylglucosamine. A mixture containing these enzymes is obtainable from almonds. After an assay for N-acetylglucosamine content in such a sample hydrolysate, the N-acetylglucosamine content, being a chitin product, may be correlated with the estimated degree of insect contamination in said foodstuff.
In another aspect, the present invention may involve a kit useful for the detection of insect contamination in a foodstuff. Such a kit would comprise: 1) a carrier being compartmentalized to receive one or more container means in close confinement therein; 2) a first container means comprising at least one enzyme capable of hydrolyzing chitin to N-acetylglucosamine; and 3) a second container means comprising reagents for colorimetric analysis of N-acetylglucosamine. The first container preferably comprises chitobiase and chitinase.
The present invention, in one preferred embodiment, involves an immunochemical method for determining the estimated degree of insect contamination in a foodstuff. This method, in this preferred embodiment, comprises the following steps: 1) assaying the content of insect myosin or components thereof in a sample of said foodstuff; and 2) calculating from said insect myosin or component content the estimated degree of insect contamination in said foodstuff.
A second and more general embodiment of an immunochemical method for determining the estimated degree of insect contamination in a foodstuff comprises the following steps: 1) obtaining an antibody specifically binding an insect antigen, preferably a protein antigen; 2) incubating a sample of said foodstuff with the antibody; 3) assaying antibody-sample interaction and correlating said interaction with the estimated degree of insect contamination in said foodstuff. While the insect antigen is preferably protein, it is most preferably the protein myosin, or components thereof.
In another view, the methods of the present invention for determining the estimated degree of insect contamination in a foodstuff may involve any method for assaying the amount of insect myosin or its components thereof in the foodstuff. Such a method would comprise: 1) subjecting a sample of said foodstuff to conditions sufficient to at least partially solubilize any insect myosin or components thereof contained therein; 2) assaying insect myosin or content of said sample; and 3) correlating the myosin components content with the estimated degree of insect contamination in said foodstuff.
The foodstuff of the above methods may be a whole or milled grain or any other material for which the degree of insect contamination is desired. The antibodies usable in the present methods of determining insect contamination are preferably one or more monoclonal types but may be polyclonal, as well as a mixture of one or both.
A kit useful for the immunochemical detection of insect contamination in a foodstuff may comprise: 1) a carrier compartmentalized to receive one or more container means in close confinement therein; 2) a first container means comprising an antibody specifically binding an insect antigen, said antibody being specifically or non specifically attached to a solid matrix; and 3) a second container means comprising detectably labeled antibody specific for said insect antigen.
An immunochemical kit useful for the detection of insect contamination in a foodstuff may also be described as one which comprises: 1) a carrier compartmentalized to receive one or more container means in close confinement therein; 2) a first container means comprising an antibody from a first antibody-producing species, said antibody specifically binding insect antigen and being specifically or non specifically attached to a solid matrix; and 3) a second container means comprising a detectably labeled antibody from a second antibody-producing species, said detectably labeled antibody specifically binding antibody from the first antibody-producing species. In these immunochemical kits the preferred insect antigen is insect myosin or insect myosin components. Said detectably labeled antibody may be labeled with a radiolabel, an enzyme label, a fluorescent label or a chromophore, although an enzyme label is preferred, said enzyme label catalyzing the formation of a visually colored product from an uncolored, differently colored or less colored substrate
In greater detail, the present invention involves a method of determining the amount of insect contamination in grain comprising the steps of: 1) preparing an aqueous solution or suspension of a homogenized grain sample; 2) substantially affixing at least a portion of said solution or suspension to a solid surface; 3) applying to said solid surface an antibody-enzyme conjugate, said antibody specifically binding insect antigen and said enzyme catalyzing formation of a colored product from a substrate; 4) washing unbound conjugate from the solid surface; 5) incubating the solid surface with an enzyme substrate under conditions allowing colored product to be formed when enzyme is present; and 6) correlating amounts of color formed with an amount of insect contamination.
Alternatively, such a detailed method of determining the amount of insect contamination in grain may comprise the steps of: 1) affixing to a solid surface an antibody having specific binding affinity for an insect antigen; 2) preparing an aqueous solution or suspension of a homogenized grain sample; 3) applying at least a portion of said solution or suspension to the solid surface to facilitate binding of any insect antigen to the affixed antibody; 4) washing the solid surface; 4) applying to said solid surface an antibody-enzyme conjugate, said conjugate antibody specifically binding the insect antigen and said enzyme catalyzing formation of a colored product from a substrate; 5) washing unbound conjugate from the solid surface; 6) incubating the solid surface with an enzyme substrate under conditions allowing colored product to be formed when enzyme is present; and 7) correlating amounts of color formed with an amount of insect contamination.
In these methods, the preferred insect antigen is insect myosin or a component thereof; the preferred enzyme is a peroxidase; and the preferred antibody or conjugated antibody may be monoclonal, a mixture of monoclonals or polyclonal.
In one embodiment, the present invention may be described as involving a method of determining the amount of insect contamination in a sample of grain. This particular embodied method comprises the following steps:
1) preparing an aqueous solution or suspension from a homogenized grain sample;
2) contacting a solid surface with said solution or suspension to substantially affix at least a portion of any insect antigen (preferably insect myosin or a component thereof) in said solution or suspension to the solid surface;
3) blocking nonspecific bind sites by incubation of a solution comprising a protein non cross reactive with the antibodies, myosin or its components;
4) incubating said solid surface with a first antibody from a first animal species, said first antibody specifically binding insect antigen;
5) washing unbound first antibody from the solid surface;
6) applying to said washed solid surface a labeled second antibody, said second antibody being from a second animal species, specifically binding the first antibody from the first animal species and said label being a detectable substance which is a fluorescent, radioactive or chromophoric compound or an enzyme (preferably peroxidase) catalyzing formation of a colored product from a substrate;
7) washing unbound labeled second antibody from the solid surface;
8) determining an amount of labeled second antibody bound to said washed solid surface; and
9) correlating the amount of bound labeled second antibody with an amount of insect contamination in said grain, said amount of bound labeled second antibody being proportional to insect antigen in the grain sample.
The most preferred label is an enzyme label and the above method involves (in place of steps 8) and 9)) the steps of:
8a) incubating the solid surface with an enzyme substrate under conditions allowing colored product to be formed when antibody-enzyme conjugate is present; and
9a) correlating amounts of color formed with an amount of insect contamination, said color formation being proportional to the amount of insect antigen present in the grain sample.
In one embodiment, the present invention involves a method of determining the amount of insect contamination in grain which comprises:
1) affixing via chemically or nonspecific binding to a solid surface an antibody having specific binding affinity for an insect antigen;
2) blocking remaining nonspecific binding sites by incubation with a solution comprising a protein non-cross reactive with antibodies or myosin; or, for chemical binding sites, blocking the remaining sites chemically;
3) preparing an aqueous solution or suspension of a homogenized grain sample;
4) applying (possibly after removal of solids) at least a portion of said solution or suspension to the solid surface to facilitate binding of insect antigen to the affixed antibody;
5) washing the solid surface to remove unbound components of the solution or suspension;
6) applying to said solid surface an antibody enzyme conjugate or an antibody conjugated to another label, said conjugate antibody specifically binding the insect antigen and said enzyme catalyzing formation of a colored product from a substrate;
7) washing unbound conjugate from the solid surface;
8) incubating (in the case of an enzyme label) the solid surface with an enzyme substrate under conditions allowing colored product to be formed when the enzyme of the conjugate is present or assaying for the other label; and
9) correlating colored product formed or label present with an amount of insect contamination, the color formation being proportional to amounts of insect antigen in the grain sample.
The antibodies in these procedures may be monoclonal or polyclonal, depending upon the particular specificities desired.
In certain cases the method of the present invention may involve antibodies labeled with a substance such as biotin and a labeled material such as avidin having high affinity for biotin. Such an alternate procedure comprises the steps of:
1) preparing an aqueous solution or suspension from a homogenized grain sample;
2) contacting a solid surface with said solution or suspension to substantially affix at least a portion of any insect antigen in said solution or suspension to the solid surface;
3) blocking nonspecific binding sites by incubation with a solution comprising a protein non-cross reactive with antibodies, myosin or myosin components;
4) incubating said solid surface with biotinylated antibody, said biotinylated antibody specifically binding insect antigen;
5) washing unbound biotinylated antibody from the solid surface;
6) applying to said washed solid surface labeled avidin, said avidin specifically binding the biotinylated antibody and said label being a detectable substance which is a fluorescent, radioactive or chromophoric compound or an enzyme catalyzing formation of a colored product from a substrate;
7) washing unbound labeled avidin from the solid surface;
8) determining an amount of labeled avidin bound to said washed solid surface; and
9) correlating the amount of bound labeled avidin with an amount of insect contamination in said grain, said amount of bound labeled avidin being proportional to insect antigen in the grain sample.
The latter procedure may be favorably modified by first coating the solid surface with a capture antibody necessarily (unless there are multiple, identical or similar, epitopes) having a binding affinity for an epitope of the insect antigen different from the epitope to which the biotinylated antibody binds.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates the repeating unit of chitin.
FIG. 2 schematically describes a chitin assay.
FIG. 3 relates to an NAG standard curve for a chitin assay and illustrates a linear relationship of color development and N-acetylglucosamine concentration in an assay according to Reissig et al. (19).
FIG. 4 relates to an enzymatic assay chitin assay system and shows the hydrolysis of chitin to NAG by enzymes from an almond emulsion.
FIGS. 5A and 5B describe an outline of procedures in the development of an insect-specific immunoassay.
FIG. 6 shows the elution profile (relative light absorption) of crude cricket myosin from Sephacryl S-300 gel filtration column.
FIG. 7 relates to the sensitivity of the myosin ELISA and shows a cricket myosin ELISA at various myosin concentrations.
FIG. 8 shows the linearity and range of the cricket myosin ELISA.
FIG. 9 shows the effects of reaction time variation (time increments) on the granary weevil ELISA.
FIG. 10 illustrates the effects of temperature on the granary weevil ELISA for immunological detection of insects.
FIG. 11 shows reproducibility of the granary weevil ELISA on successive days for the immunological detection of insects.
FIG. 12 illustrates the statistical reproducibility of the granary weevil ELISA (data from 5 plates run on different days).
FIG. 13 describes the sensitivity of a granary weevil myosin ELISA assay in the presence of flour.
FIG. 14 shows the sensitivity of a granary weevil myosin ELISA.
FIGS. 15A through 15E show an embodiment of the test strip assay of the present invention; FIG. 15A shows dropping of a test solution on the strip; FIG. 15B shows subsequent addition of an antibody enzyme conjugate solution; FIG. 15C illustrates washing the test strip of unbound materials; FIG. 15D shows addition of enzyme substrate to the strip; and 15E illustrates developed color proportional to the amount of insect antigen in the test solution.
FIGS. 16A through 16D show a second embodiment of the test strip assay of the present invention; FIG. 16A shows test strip immersed in a solution or suspension of test foodstuff; FIG. 16B washed test strip immersed in antibody enzyme conjugate solution; FIG. 16C washed test strip immersed in a solution containing enzyme substrate; and FIG. 16D colored product. visualized on test strip. The enzyme-labeled anti-granary weevil antibody binds to a different myosin epitope than the anti-granary weevil antibody.
FIG. 17A shows, with an ELISA for grain insects using antibody to cricket myosin, the relationship of antigen concentration in soybean and ELISA response at 414 nm with a 1:1,000 antibody concentration for two reaction times.
FIG. 17B shows, with an ELISA for grain insects using antibody to cricket myosin, the relationship of antigen concentration in soybean and ELISA response at 414 nm with a 1:10,000 antibody concentration.
FIG. 18A shows the relationship of antigen concentration in wheat and ELISA response (anti-cricket myosin antibody) at 414 nm with a 1:1,000 antibody concentration.
FIG. 18B shows the relationship of antigen concentration in wheat and ELISA response (anti-cricket myosin antibody) at 414 nm with a 1:10,000 antibody concentration.
FIG. 19 illustrates the replicability detection of granary weevils (5 weevils/sample) in a grain mixture by immunoassay. The average was 0.45 and range 0.433 to 0.472.
FIG. 20 shows the sandwich ELISA response over a series of insect antigen concentrations at various dilutions of capture antibody. The capture antibody (Ab) dilutions are shown for each symbol.
FIG. 21 illustrates the sandwich ELISA response at a series of capture antibody (capture Ab) dilutions and various antigen concentrations. The capture antibody dilutions are shown for each symbol.
FIG. 22 schematically shows the sandwich ELISA response at a series of antigen concentrations and at various dilutions of antibody-horseradish peroxidase (Ab-HRP) conjugate. The Ab-HRP dilutions are shown for each symbol.
FIG. 23 illustrates the sandwich ELISA response at a series of Ab-HRP dilutions and at several antigen concentrations. The Ab-HRP dilutions are shown for each symbol.
FIG. 24 shows the sandwich ELISA response at a series of flour levels with four different antigen concentrations. The antigen concentrations are shown for each symbol.
FIG. 25 illustrates sandwich ELISA response linearity at a series of antigen concentrations and at five flour levels. The amount of flour is shown for each symbol.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The detection of chitin or insect-specific antigens for determination of insect or insect parts in bulk foodstufs or crops is an object of the present invention.
Insofar as granular foodstuffs such as grain are concerned, immunospecific detection of insect contamination could lead to ready and efficient mechanical cleaning, e.g., by aeration to remove insect pests characteristically dwelling outside grain particles, to produce commercially acceptable bulk grain at reasonable cost.
An efficient method for integrated pest management of growing or mature crops could be developed using the insect detection procedures of the present invention. The specificity of preferred immunoassays could be arranged to detect general insect levels in such crops and to differentiate harmful versus beneficial insect presence. Hence, pesticide use could be minimized and designed to alleviate specific pest problems.
The following Examples relate to preferred specific embodiments of the insect contamination assays of the present invention and are not meant to limit the scope.
EXAMPLE 1
Chitin Analysis
A biochemical test for chitin is schematically shown in FIG. 2. Chitin, a beta [1-4] homopolymer of N-acetylglucosamine (NAG}, is preferably converted to its monomeric constituent, N-acetylglucosamine, by hydrolysis. This hydrolysis may be induced by enzymes or chemical means, e.g., with acid or alkali. Sensitive assays (e.g., colorimetric) for the N-acetylglucosamine product are available.
It has long been known that certain types of chitin, when subjected to treatment with 0.2% iodine in potassium iodide, followed by treatment with 1% sulfuric acid, develop colored products (17). A more recent modification of this procedure avoids the use of sulfuric acid and gives more uniform color production (18). The test has been used to examine the structural features of chitin in tissues. Such direct color tests for chitin may provide a means for identifying chitin in grains and grain products. One could envision simply crushing grain (or using milled grain) and adding a staining solution, followed by a simple photometric scanning system. These reactions may be adapted for the study of insect contamination.
Several very sensitive methods for N-acetylglucosamine detection have been reported in the literature. The procedure of Reissig, Strominger and Leloir (19) appears to be particularly well suited to the purposes of the present invention and is capable of detecting as little as 3×10 -10 moles of N-acetylglucosamine. Other procedures for NAG assay, such as those of Ride et al. (20) and Tsuji et al. (21) should be usable after appropriate adaptation.
The NAG assay method of Reissig et al. (19) was tested for sensitivity as follows:
One hundred microliter (ul) of aqueous NAG sample and 20 ul of K (0.8M potassium tetraborate, pH 9.1) were mixed, incubated at 100° C. for 3 minutes and cooled. Six hundred ul of DMAB reagent (1 g dimethylaminobenzaldehyde in 100 ml of analytical reagent grade glacial acetic acid with 12.5% 10N HCl) was added to the cooled mix and this second mixture was incubated at 37° C. for 20 minutes. After cooling to room temperature, the absorbance at 585 nm (nanometer) was measured. FIG. 3 shows the repeatability and linearity of this NAG assay, run at levels expected to be encountered with insect infestation of grain samples.
The conversion of chitin to NAG is a rate-limiting step in preferred available chitin analyses. While acid or alkaline hydrolysis of chitin can be dependable, they generally involve potentially hazardous reagents and may require extensive periods of time. The enzymic hydrolysis of chitin for the purpose of NAG production and assay thereof for insect detection has been accomplished as part of the present invention.
An efficient enzymatic degradation of chitin to N-acetylglucosamine requires the use of two different enzymic hydrolases: chitinase and chitobiase. These chitin-degrading enzymes are present in a wide variety of bacteria and fungi but are difficult to obtain commercially in appropriate quantities and purity. Based on the report of Wadsworth (22), the use of an enzyme preparation from almond emulsions was investigated. This enzyme preparation had been reported to have both chitinase and chitobiase activities. After considerable modification of assay conditions, and using purified chitin as a substrate, it was demonstrated that this new procedure can provide excellent linearity of NAG production over a broad range of chitin concentrations using incubation times as short as 30 minutes.
Under the following conditions, the above enzyme preparation from almond emulsions was used to hydrolyze chitin.
Certain beta-glucosidase preparations were found to have chitobiase activity and that the enzyme preparation available from almonds was contaminated with chitinase. The suitability of the almond extract in hydrolyzing chitin was investigated, and a modification of Reissig's NAG assay (19, 22) was used to quantify the NAG produced.
Method
A glycine/HCl buffer was used in all NAG assays because it was found that citrate buffer interfered with the NAG assay. A glycine/HCl buffer (0.05M, pH 3.5) was found to perform significantly better than a citrate buffer.
An incubation mixture was prepared which contained 1 ml of 0.05M buffer (pH 3.5), 0.5 ml of a 8 mg betaglucosidase/ml buffer (enzyme from almonds, Sigma, No. G0395, lot#38F-4031), 0.5 ml dH 2 O and 2.5 mg purified grade chitin (Sigma, No. C-3641, lot#107F-7115). The substrate blank (control) contained 1.5 ml of the buffer, 0.5 ml of dH 2 O, and 2.5 mg chitin. Each incubation mixture was stirred continuously with magnetic stir bars from 30 minutes at RT.
NAG Assay
The incubation mixture was centrifuged at 900× g for 3 minutes at 4° C. To 0.5 ml supernatant, 0.1 ml of potassium tetraborate was added, and heated in a vigorously boiling water bath for 8 minutes. After cooling with tap water, and adding 3 ml of 1% paraDimethylaminobenzaldehyde (DMAB, Aldrich lot#MV 00929LV; 10 g DMAB in 100 ml of 12.5% v/v 10N HCl in analytical grade glacial acetic acid is diluted with 9 volumes reagent grade glacial acetic acid just prior to use). After vortexing and placing in a 37° C. water bath for 20 minutes, then cooling with tap water the absorbance at 585 nm against a distilled water blank was determined (Beckman DU Model 2400). NAG concentration was determined by treating 0.5 ml aliquots of NAG reference solutions (1×10 -5 , 5×10 -5 , 1×10 -4 , 2×10 -4 , 4×10 -4 , 1×10 -3 M) as above, beginning with the addition of potassium tetraborate.
Results
Ride and Drystale's (20) assay was used to determine the chitin hydrolysis using beta-glucosidase rather than chitinase. After about 35 minutes of incubation, the substrate blank had an average absorbance in excess of 0.850, while the incubation mixture containing the enzyme gave an average absorbance in excess of 1.07. Hence, high absorbances were found after incubation for as little as about 35 minutes, but the solutions containing the beta-glucosidase all had significantly higher absorbances than the substrate blanks (unlike when chitinase alone was used).
In two initial chitinolysis experiments using betaglucosidase, a practical grade chitin (Sigma, lot#12F-7060) substrate and a Gly/HCl buffer (0.05M, pH 3.5), the absorbance after 30 minutes of incubation was only between 0.02 and 0.04 absorbance units (about 2×10 -5 M NAG produced). The control (substrate blanks) gave a 0.00 absorbance reading. With purified grade chitin as the substrate, incubation with beta-glucosidase for 30 minutes gave an absorbance value that exceeded 0.1 units, whereas incubation for 60 minutes gave an absorbance that exceeded 0.2 units. This translated into 7.1×10 -5 M and 1.4×10 -4 M NAG produced, respectively. Hence, beta-glucosidase catalyzed chitinolysis of practical grade chitin, as was expected.
In a later assay, beta-glucosidase was incubated with purified grade chitin for times of 0.5 hours, 1.5 hours, 19.17 hours, and 24 hours. Absorbance value ranged from ca. 0.206 for the 0.5 hour incubation to over 1.03 for the 24 hour incubation (1.14×10 -4 M NAG and 5.74×10 -4 M NAG, respectively). In another assay, it was found that a 0.5 hour incubation gave an absorbance of 0.172 and that the 24 hour incubation yielded 1.06, corresponding to 8.05×10 -5 M and 5.73×10 -4 M NAG, respectively. The following observations were also made:
1. The NAG assay shows a linear relationship (correlation coefficient, r, is greater than 0.99) between absorbance and [NAG] for concentrations less than or equal to 2×10 -4 M. Significant "flattening" occurs after [NAG]=4×10 -4 M.
2. NAG reference solution are preferably used each time an assay is run because final absorbances may vary slightly.
3. The control (substrate blank) for the hydrolysis of chitin from Sigma (purified or practical) gives a significantly lower absorbance (less than 1/10th) than the solution containing the beta-glucosidase with the chitin.
4. The Beckman DU Model 2400 Spectrophotometer gave dependable absorbance readings.
Free NAG produced at various periods of time was colorimetrically determined by the method of Reissig et al. (19) adapted for the present purpose. One hundred microliters (ul) of aqueous NAG sample and 20 ul of K 3 BO 3 (0.8M potassium tetraborate, pH 9.1) were mixed, incubated at 100° C. for 3 minutes and cooled. Six hundred ul of DMAB reagent (lg dimethylaminobenzaldehyde in 100 ml of analytical reagent grade glacial acetic acid with 12.5% 10N HCl) was added to the cooled mix and this second mixture was incubated at 37° C. for 20 minutes. After cooling to room temperature, the absorbance at 585 nm (nanometers) was measured. Data from the enzyme hydrolysis technique are shown in FIG. 4, which depicts the amount of NAG-dependent color developed upon colorimetric assay as described above when chitin-containing samples are incubated with enzymes for varying times. Note that a readily measured amount of color (0.17 absorbance units) was produced even when the enzymatic hydrolysis was carried out for only a 30 minute incubation time. The enzyme hydrolysis procedure provides an assay which is of comparable sensitivity to the chemical methods and promises to reduce the time required for accurate analyses.
The experiments described above were carried out using a dual enzyme system consisting of both chitinase and chitobiase from almonds. These results showed both a rapid and linear release of N-acetyl glucosamine from purified crab shell chitin. Readily detectable amounts of N-acetyl glucosamine were produced with as little as 15 minutes incubation of the enzymes with the chitin substrate.
Subsequent experiments were carried out using the granary weevil Sitophilus oranarius as the source of chitin. Whole weevils were frozen in liquid nitrogen in a test-tube and crushed to a powder with a pestle. Glycine/HCl buffer (0.05M, pH 3.5) was then added to yield a final concentration of 2.5 mg weevil/ml. Aliquots of this suspension were then subjected to chitinase/chitobiase hydrolysis. The amount of N-acetyl glucosamine released was shown to be proportional both to the amount of insect material added and to the period of incubation. However, the degree of hydrolysis was consistently considerably less than was observed with purified crab shell chitin. Possible reasons for these results include the presence of proteases in the ground insects which would diminish the activity of the chitinolytic enzymes; the presence of enzyme inhibitors in the extract or a need for the insect chitin to be processed further to generate a more suitable substrate for the enzymatic hydrolysis.
It is thus feasible for the degree of contamination by insects or insect parts to be detected in foodstuffs such as whole or milled grain by the direct or indirect assay of chitin.
EXAMPLE 2
Immunological Test System
Immunological assay procedures offer an exceptionally sensitive means for detecting biological compounds. The clinical assays for human chorionic gonadotropin, available as over the counter pregnancy tests, as well as assays for pesticide residues and for mycotoxins such as aflatoxin demonstrate the utility of this approach. In the most preferred immunological assay procedures of the present invent, an insect protein antigen is utilized. The muscle protein myosin, the most preferred insect antigen, is present in relatively large quantities in all life stages of insects and is found in insect remains as well. Myosin is a slowly evolving protein, so that antisera prepared against this protein cross-reacts with the myosins of other insect species.
An outline of the procedures used to develop a laboratory-style immunological assay for insect materials is given in FIG. 5. Initial studies were carried out using cricket myosin. Using antibodies obtained against cricket myosin and its components in rabbits, an ELISA (enzyme linked immunosorbent assay) was developed. It was demonstrated that this type of assay had excellent sensitivity and the potential for determining cross-reactivities with a wide variety of grain insects.
The experiments and results detailed herein establish a proof of principle test system for the development of an immunological assay to detect insect specific protein contaminating whole and milled grain. Using antibodies against an insect myosin as different from grain pest myosin as cricket myosin, a substantial cross-reaction with crude extracts from a broad range of the most common insect pests of stored grain was demonstrated. If it is assumed the average grain pest weighs approximately 2.5 mg, and that 1% of this weight is myosin (i.e., 2.5×10 -5 g of myosin), then the average grain pest contains at least 1,250 times the myosin necessary to give a positive test result in the myosin ELISA described here. The assay was also shown to be linear over a broad range of antigen concentration. It should be noted that the detection limit and linear response range of the assay are most likely limited by the protein absorptive capacity and characteristics of the polystyrene microtiter plates.
The adaptation of this laboratory-based assay to a reagent strip ("dip-stick") format is currently being developed. "Dip Stick" ELISA's are easy to perform, rapid, and inexpensive. Successful adaption of the myosin ELISA to this reagent strip format would allow relatively untrained workers to test for insect contamination of whole and milled grain at granaries, for example. Early work has focused on the enzyme linked immunospot (ELISPOT) assay reviewed by Monroe (33). The ELISPOT assay is essentially an ELISA performed on nitrocellulose, which has a much greater protein absorptive capacity than polystyrene. Preliminary results indicate the myosin ELISPOT is at least 30 times more sensitive than the myosin ELISA. Here, the average grain pest would have over 50,000 times the myosin needed to give a positive test.
As encouraging as these results with antibodies to cricket myosin have been, an ELISA using antibodies directed against the myosin of a grain pest may offer certain improvements. The present inventors have recently extracted myosin from Sitophilus granarius (granary weevil), and used it to produce polyclonal antibodies. These antibodies showed broad cross-reaction with crude extracts from a wide variety of other grain pests. Development of a dipstick assay based on these antibodies is also currently in progress.
Monoclonal antibodies to granary weevil myosin will be prepared by the usual methods well-known in this area. Monoclonal antibodies should allow even more quantitative ELISA and ELISPOT assays to be developed, and will provide an almost unlimited source of antibodies specific for the same antigenic determinants (epitopes). This will allow more ready standardization of the assay, which is important in the development of an optimal assay for use in the field. Once a standardized assay has been developed, it may be automated and incorporated for the detection of insect contamination of grain into procedures already in use at granaries for testing grain hardness and moisture content. Finally, further development of the monoclonal antibody test might also allow not only quantitation of insect infestation, but identification of the species of infesting insect.
EXAMPLE 3
Materials and Methods Involved in an Immunoassay
The myosin extraction procedure used was an adaptation of those used by Chaplain (23) and Woods (24). Crickets were obtained live from the American Angler Tackle Center (Austin, Tex.) and kept at -20° until used. Upper rear leg segments were removed from 150 crickets, and homogenized in a Waring Commercial blender with enough 0.3M sucrose/20 mM Tris-Cl/1 mM EDTA (pH 7.2) to create a semi-thick slurry. Structural residue was removed by centrifugation at 2500 rpm (SS-34 rotor) for 20 min. The pellet was then extracted with stirring in ten times its volume of 0.7M KCl/20 mM Tris-Cl(pH 7.8) for 6 hrs. at 4° C. After centrifugation at 8,000 rpm for 25 min., the supernatant was carefully removed. Actomyosin was precipitated by dilution of the supernatant to an ionic strength of 0.05 using deionized H 2 O, resuspended in a minimal amount of 0.6M KCl/5 mM MgCl 2 (pH 8.0 with NaHCO 3 ), shaken, and centrifuged at 36,000 rpm (type 40 rotor) for 2 hrs. The supernatant was then dialyzed overnight at 4° C. against 0.05M NaCl. Afterwards, the precipitate was removed by centrifugation at 10,000 rpm (SS-34 rotor) for 20 min., and the pellet resuspended in enough 0.5M NaCl to give a solution with an absorbance at 280 nm of 3.0 (determined using a Beckman DU-50 spectrophotometer). A Sephacryl S-300 (Pharmacia) gel filtration column was packed (1.5 cm×69 cm) and equilibrated with 0.5M NaCl at a flow rate of 0.8 ml/min. A 0.5 sample was loaded on to the column and 2 ml fractions were collected. Protein elution was followed by monitoring the absorbance of the fractions at 280 nm. Fractions corresponding to peaks were then frozen at -20° C. (the elution pattern is shown in FIG. 6). Myosin pellets were also purified using the ammonium sulfate precipitation procedure of Wang et al. (25). After the precipitate was resuspended and dialyzed as above, the final solution was stored under liquid N 2 .
Myosin purity was then evaluated using sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE). The method used was a modification of the procedures of Weber and Osborn (26), and is detailed in the SIGMA Chemical Company Technical Bulletin No. MWS-877 (1986). Myosin pellets were resuspended in 0.5M NaCl at an approximate protein concentration of 3 mg/ml, as determined by the method of Bradford (27). Fractions from the S-300 column were also analyzed using SDS-PAGE, and were combined as is with sample buffer. Analytical runs on 5% gels were performed with 20-25 ug of total protein; preparative gels were run with 50 ug of total protein. Gels were stained overnight in 25% isopropanol/10% acetic acid/0.1% Coomassie Blue R-250/ and 0.1% cupric acetate in deionized H 2 O, and destained in 10% ethanol/10% acetic acid in deionized H 2 O until the background staining reached an acceptable level. The gels were scanned using a GS-300 densitometer (Hoefer Scientific Instruments, San Francisco, Calif.) at 585 nm. Final protein concentrations per band were then calculated by cutting out the band peaks, weighing them, and correlating this to the total protein concentration.
Protein bands corresponding to myosin heavy chain were excised from the gels, diced with a single edged razor, and ground in a tissue grinder in 0.15M NaCl following an adaptation of the procedure of Hunter et al. (28). The final mixture, containing approximately 100 ug (microgram) of myosin heavy chain/ml, was stored at -20° C. until used. Antibodies to the denatured heavy chain of myosin were raised in 4 month old male New Zealand white rabbits using an adaptation of the procedures of Hurn and Chantler (29). For primary immunization, 0.5 ml of myosin gel mixture (50 ug of myosin heavy chain) was suspended in 0.5 ml Freund's complete adjuvant (Colorado Serum Co., Denver, Colo.), and injected subcutaneously in multiple sites on the hind quarters of the rabbit. Booster injections were given at approximately one month intervals after primary immunization, and consisted of 50 ug myosin heavy chain gel mixture (first and second boosts), or 60 ug gel mixture (third and fourth boosts), suspended in 0.15M NaCl and injected subcutaneously in multiple sites. Total volume for all booster injections never exceeded 1.5 ml. Blood was drawn from a marginal ear vein 10 days later, and allowed to clot overnight at room temperature. The next day, the clot was removed and the serum stored at -20° C.
Enzyme linked immunosorbent assay (ELISA) was performed using an adaptation of the procedure of Browning et al. (30). Microtiter wells were coated with 50 ug of the antigen solution. Antigens were usually dissolved in 0.5M NaCl. Rabbit antiserum was always diluted in buffer HNAT (10 mM Hepes-KOH, pH 7.6, 0.2% bovine serum albumin, 0.02% Tween 80) and 50 ug of first antibody was added to each well. Blank wells were prepared using rabbit preimmune sera. The second antibody was goat anti-rabbit IgG conjugated to horseradish peroxidase (Kirkegaard and Perry Laboratories). Incubations with antigen and antibodies, as well as blocking incubations, were all for 30 min. After addition of the reaction mixture, the microtiter plates were incubated for 20 min. at room temperature, and the reaction stopped by the addition of 0.1 ml 0.01% NaN 3 to each well. The absorbance was then measured either at 405 nm using a Bio-Tek Instruments Model EL310 EIA plate reader or at 414 nm using a BIORAD EIA plate reader model 2510.
Crude extracts of grain pests were prepared by taking 100 mg of the dead insect (stored at -80° C.) and grinding them up in 2 ml of 0.5 M NaCl. The resulting mixture was then centrifuged at 5000 rpm (SS-34 rotor) for 20 min, and the supernatant stored under liquid N 2 until tested.
EXAMPLE 4
Immunoassay Development
Myosin was extracted from thigh muscles of the common cricket following procedures detailed in Example 2 and 3. The crude myosin preparation was further purified on a Sephacryl (Pharmacia) S-300 gel filtration column, and the elution profile of this column is shown in FIG. 6. SDS-polyacrylamide gel electrophoresis of the crude myosin and fractions from the S-300 column was performed. After SDS-PAGE, the major bands in the crude myosin gel corresponded to myosin heavy chain (200 kD) and what may be a paramyosin subunit (105 kD). Paramyosin is a muscle protein limited in distribution to the invertebrates and forms a core in the thick filaments around which myosin wraps (31). Minor bands correspond to actin (ca. 43 kD), tropomyosin (ca. 28 kD) and myosin light chain (ca. 18 kD). As seen from S-300 column fraction PAGE gels, column gel filtration removed lower molecular weight contaminants from the crude myosin preparation. However, the apparent paramyosin was still present. Resuspended crude myosin pellets were also purified following the ammonium sulfate precipitation procedure of Wang et al. (32). SDS-polyacrylamide gels of a myosin preparation before and after the salt fractionation showed that a substantial amount of paramyosin contamination remained even after ammonium sulfate precipitation, although lower molecular weight contaminants were removed.
Antibodies directed against cricket myosin heavy chain were obtained by initially immunizing male New Zealand white rabbits with cricket myosin heavy chain bands excised from polyacrylamide gels of the S-300 column fractions. Crude cricket myosin could also be used as an immunogen to generate appropriate antibodies. Booster injections were prepared using myosin heavy chain bands from gels of ammonium sulfate precipitation purified myosin. These antibodies were then used to develop an enzyme linked immunosorbent assay (ELISA) for cricket myosin. Some details of ELISA procedures are given in Example 1. The ELISA procedure was adapted from that of Bahr et al. (34) and may be more fully described as follows. Fifty ul of antigen solution or sample was added to a microtiter well and the microtiter plate was incubated at room temperature (RT) for 30 minutes. Excess antigen or sample was removed by a single washing with buffer HN (10 mM HEPES/KOH pH 7.6, 150 mM NaCl). One hundred ul of buffer HNA (buffer HN with 1% bovine serum albumin (BSA)) was then added to each well, followed by a 30 min incubation at RT. Buffer HNA was removed and each well washed twice with buffer HNAT (buffer HN with 0.2% BSA and 0.02% TWEEN 80). Fifty ul of an antibody solution appropriately diluted in buffer HNAT (the antibody being specific for insect myosin or a component thereof) was added to each well and incubated for 30 min at RT. The antibody solution was removed and each well washed thrice with buffer HNAT. Fifty ul of a solution comprising goat antibody specific for rabbit IgG and conjugated to horseradish peroxidase was then added to each washed well. After a 30 min incubation at RT, unbound goat antibody conjugate was removed and each well washed thrice with buffer HNAT. A reaction mixture was prepared by mixing 50 ul ABTS (70 mg 2,2'-azino-bis-3-ethylbenzthiazoline sulfonic acid (Sigma); 5 ul 30% H 2 O 2 and 4.95 ml of 0.1M sodium citrate-citric acid, pH 4.2. One hundred ul of reaction mix was added to each well and incubated (preferably for 10-20 minutes). If the microtiter plate is to be scored for developed color on a spectrophotometer, color development is stopped by addition of 100 ul of stopping reagent (1.82×10 -3 M NaN 3 ) and the color produced measured spectrophotometrically at 414 nm.
The sensitivity of the myosin ELISA was evaluated by testing the ability of the ELISA to detect myosin in dilutions of a crude cricket myosin solution. FIG. 7 is a plot of the response of the myosin ELISA as a function of antigen concentration, and shows that the myosin ELISA can easily detect low (nanogram) quantities of crude myosin. The leveling of the assay response at higher total protein concentrations can be attributed to reaching the protein absorptive capacity of the polystyrene wells in the microtiter plates. The linear range of the myosin ELISA was also determined, and is shown in FIG. 8. The assay's linear response easily spanned a ten-fold total protein concentration range (22ng-380 ng), and demonstrated usability as a quantitative assay for insect myosin.
The ability of the cricket myosin-based ELISA to detect myosin in crude extracts of a wide variety of common grain pests was evaluated, and the results are reported in Table 1. The cricket myosin ELISA had a strong cross reaction with crude extracts of this broad range of the most common and serious pests of stored grain. This shows that the cricket myosin-ELISA can detect myosin in all of the grain pests tested and affirms that a cricket myosin-based ELISA may be used for detecting a wide variety of insect pests contaminating foodstuffs such as whole and milled grain.
TABLE 1______________________________________GRAIN PESTS WHOSE CRUDE EXTRACTS WEREDETECTABLE USING A CRICKETMYOSIN-BASED ELISA Assay ResponseGrain Pest (O.D. at 405 nm)______________________________________Sitophilus zeamais (maize weevil) 0.18Sitophilus granarius (granary weevil) 0.40Sitophilus oryzae (rice weevil) 0.28Trogoderma variabile (warehouse beetle) 0.78Trogoderma glabrum 0.80Tribolium castaneum (red flour beetle) 0.78Tribolium confusem (confused flour beetle) 0.39Oryzaephilus mercator (merchant grain beetle) 0.89Rhyzopertha dominica (lesser grain borer) 0.29Prostephanus truncatus (larger grain borer) 0.75Lasioderma serricorne (cigarette beetle) 0.39Stegobium paniceum (drugstore beetle) 0.22Callosobruchus maculatus (cowpea weevil) 0.76Attagenus megatoma (black carpet beetle) 0.581:500 dilution of crude cricket myosin 0.42______________________________________
EXAMPLE 5
Granary Weevil Myosin Immunoassay
Granary Weevils were obtained from the U.S. Department of Agriculture Research Service, Department of Entomology, University of Wisconsin, Madison, Wis. 53706. Antisera to crude granary weevil myosin were prepared by a procedure analogous to that of Example 2. An ELISA assay analogous to that described above for cricket myosin was developed. Table 2 shows a variety of insects detectable using this granary weevil myosin-based ELISA.
TABLE 2______________________________________Grain Pests Detectable Using anAnti-granary weevil Myosin ELISA______________________________________Sitophilus zeamais (maize weevil)Sitophilus oryzae (rice weevil)Trogoderma variabile (warehouse beetle)Trogoderma glabrumTribolium castaneum (red flour beetle)Tribolium confusem (confused flour beetle)Oryzaephilus mercator (merchant grain beetle)Rhyzopertha dominica (lesser grain borer)Prostephanus truncatus (larger grain borer)Lasioderma serricorne (cigarette beetle)Stegobium paniceum (drugstore beetle)Callosobruchus maculatus (cowpea weevil)Attagenus megatoma (black carpet beetle)Alphitobius diaperinus (lesser mealworm)Plodia interpunctella (indian mealworm)______________________________________
A number of parameters of the granary weevil myosin ELISA system were examined to be sure the assay procedure operated at optimal sensitivity and also provided data within a short period of time. The effect of varying reaction times for the assay is shown in FIG. 9. Using a 96-well microtiter plate system it was found that a minimum of approximately 15 minutes of incubation time was appropriate for this type of assay. More rapid immunoassays, for example, using a test-strip type assay described elsewhere herein, may be developed. The effect of temperature on the assay procedure is illustrated in FIG. 10. While the assay is indeed affected by temperature, the effect is not large and the small changes in the assay observed with varying temperature can readily be adjusted by including control samples in the assay system. It is important to note that the assay procedure is relatively insensitive to temperature in the normal range of operating conditions.
Another concern was that any assay procedure for detecting insect contamination has to be highly reproducible. Data from several successive days of testing using the Sitophilus granarius (grain weevil) antibody system are shown in FIGS. 11 and 12. In the FIG. 12, the error bars represent one standard deviation on either side of the average value. These data represent a collection of standard curves and the standard curves differ very little from day to day. It is anticipated that, for optimal accuracy, standards would be run each day when actual tests for contamination are being carried out.
It was necessary to establish that such immunological assays functioned properly in the presence of ground grain. Assays for live or dead insect remains in whole kernels will require grinding the grain and extracting the myosin or components of myosin. A similar extraction procedure is required for milled grain. A preliminary set of data obtained for myosin admixed with flour is presented in FIG. 13. Although some background absorption was noted in these experiments, the requisite sensitivity for insect myosin was otherwise not substantially changed.
The sensitivity of the granary weevil ELISA system is illustrated in FIG. 14. Clearly, such an immunological test provides both linearity over a broad range of myosin concentrations and has the requisite degree of sensitivity. In this type of assay it is estimated that a level of contamination of one insect per 1,000 grams of grain would be equivalent to approximately 90 nanograms of antigen. Tests have also established that such an ELISA assay can be extended in sensitivity by at least about five fold.
These results indicate that the assay is: 1) sufficiently sensitive; 2) the assay detects a broad range of insects; and 3) may be adapted to a rapid, inexpensive, and easy-to-use format.
EXAMPLE 6
Development of a Test Strip Assay
For purposes of field use, a convenient system of immunoassay may be readily developed. For example, as shown in FIGS. 15A-15E a test strip would have a substantially colorless area for receipt of a drop of test solution. The test solution would be an aqueous extract or suspension of, for example, a homogenized grain sample. A portion of this aqueous extract would then be applied to the test strips. The test strip would then be dried to enhance affixation of any insect antigen present. Subsequently, an antibody conjugated with a label such as an enzymic label would be added to the test strip. After washing unbound antibody conjugate away, a substrate solution for the enzyme would be added and color development observed. The extent of color development would be proportional to the amount of insect antigen (such as myosin or components thereof) present in the test solution.
FIGS. 16A-16D represent a more generally accepted model for such a test strip assay. In this model, the test strip 2 would contain a substantially white center of a substance such as nitrocellulose (e.g., Immobilon) which has been treated to bind an immunoglobulin 4 having specific affinity for an insect antigen such as myosin (M). The test strip would be characteristically blocked for nonspecific absorption and dipped in an aqueous solution or suspension 6 in which a grain sample has been homogenized. This would allow any antigen (M) present in the aqueous solution or suspension 6 to bind to the antibody 4 on the test strip 2. After washing 8 unbound material from the test strip 2, the test strip would then be immersed in a solution 10 containing an antibody specific for the insect antigen (M) and conjugated to an enzymic (E) or other label 12. After washing 14 away unbound antibody-enzyme conjugate 12, the test strip 2 would be dipped in a solution 16 comprising a substrate(s) for the enzyme (E) which is converted by the enzyme into a colored product (or assayed for the other label). The test strip may then be removed from the solution and the production of a colored product 18 observed when the antibody-enzyme conjugate was bound to the test strip through an insect antigen. The extent of color development or other label would be proportional to the amount of insect antigen (such as myosin or a component thereof) present in the test solution.
Such test strip assays may utilize polyclonal, monoclonal or a mixture of monoclonal antibodies and a variety of enzyme labels and color-producing substrates to maximize the ease of use and sensitivity.
EXAMPLE 7
Detection of Insect Myosin in Grain Samples
The immunological procedures described above were used to detect insect myosin in samples of corn, soybean, rye, spring wheat, hard winter wheat, oats, hulled barley, whole barley, Wehani-rice and brown rice.
Ten grams of grain were ground in a small Waring blender. 20 ul of 0.5N NaCl was added and the mixture was stirred and mixed well. The mixture was then centrifuged for 10 min. at 15,000 g. The supernatants were used to prepare test samples by addition of purified cricket myosin in varying amounts, as indicated in FIGS. 17A-18B. The test samples were then assayed by the standard ELISA procedure. Antibody concentrations were as indicated on the FIGS. 17A-18B.
FIG. 17A shows the relationship of antigen concentration in soybean and ELISA response at 414 nm with a 1:1000 serum antibody dilution. FIG. 17B shows the relationship of antigen concentration in soybean and ELISA response at 414 nm with a 1:10000 serum antibody dilution.
FIG. 18A shows the relationship of antigen response concentration in wheat and ELISA at 414 nm with a 1:1000 serum antibody dilution. FIG. 18B shows the relationship of antigen concentration in wheat and ELISA response at 414 nm with a 1:10000 serum antibody dilution. Results analogous to those of 17A-18B were obtained from samples of the other grain, bean and corn foodstuffs listed above.
Ten grams of grain were mixed with 5 granary weevils and ground in a small Waring blender. 20 ml of 0.5N NaCl was added and the mixture was stirred and mixed well. The mixture was then centrifuged for 10 min. at 15,000 g. The supernatant was used to prepare a test sample. Duplicate samples were assayed for ELISA response on five successive days (see FIG. 19).
EXAMPLE 8
Sandwich ELISA Procedure
Wells of a microtiter plate were coated with 50 ul of purified capture polyclonal antibody diluted (1:1000) in 0.15M sodium phosphate, pH 7.5. After a one hour incubation at room temperature, the wells were aspirated, and washed once with buffer HN. The wells were then incubated for one hour at room temperature with 100 ul buffer HNA. Afterwards, this solution was removed, and the wells washed twice with buffer HNAT. To each well was then added 50 ul of 0.15M sodium phosphate, pH 7.5/0.02% Tween-80, followed by 50 ul of the test solution, usually in 0.15M sodium phosphate, pH 7.5. After a 45 minute incubation at room temperature, the wells were emptied, and washed three times with buffer HNAT. Polyclonal antibody-horseradish peroxidase (HRP) conjugated by glutaraldehyde (1:500 dilution in HNAT) was then added to each well, followed by a thirty minute incubation at room temperature. The antibody conjugate was then removed, and the wells washed three times with buffer HNAT. To each well was then added 100 ul of the ABTS reaction mixture. After a reaction time of 15 minutes, the reaction was stopped by the addition of NaN 3 , and the absorbance read at 414 nm. FIG. 20 shows the sandwich ELISA response over a series of insect antigen concentrations at various dilutions of capture antibody. FIG. 21 illustrates the sandwich ELISA response at a series of capture antibody dilutions and various antigen concentrations. FIG. 22 represents the sandwich ELISA response at a series of antigen concentrations with different dilutions of antibody-HRP conjugate. FIG. 23 shows the sandwich ELISA response at a series of Ab-HRP dilutions and at various antigen concentrations.
EXAMPLE 9
Sandwich ELISA in the Presence of Flour Spiked with Free Antigen
Five groups of five sample tubes were prepared containing 0, 50, 150, 300, and 600 mg of wheat flour. A sample of each group was then spiked with 2.5 ml of the following concentrations of antigen (crude cricket myosin) in 0.15M sodium phosphate, pH 7.5: 0 ng/ul, 0.5 ng/ul, 1 ng/ul, 1.5 ng./ul, 2 ng/ul. The sandwich ELISA was performed as above, and the data analyzed for the ability of the sandwich ELISA to perform in the presence of different amounts of flour.
FIG. 24 shows the sandwich ELISA response at a series of flour concentrations with four different antigen concentrations. FIG. 25 illustrates sandwich ELISA response linearity at a series of antigen concentrations with five concentrations of flour.
EXAMPLE 10
Avidin/Streptavidin-Biotin ELISAs
Antibody Purification and Conjugation Procedure were conducted as follows: Antibodies were purified following an adaption of the method of Ey (35) on a three cm 3 column of immobilized (6% cross-linked beaded agarose) Protein A (Pierce). A 0.8 ml sample of serum (rabbit #780, Jun. 9, 1989) was combined with 2 ml column buffer (0.14M sodium phosphate, pH 8.0, 0.05% NaN 3 ), loaded on to the column, and incubated for 10 minutes. Column buffer was then passed through the column at a flow rate of 0.4 ml/min., and 1.0 ml fractions were collected until the absorbance at 280 nm of the fractions returned to about zero (23 fractions). Elution buffer (0.1M sodium citrate/citric acid, pH 4.0, 0.05% NaN ) was then passed through the column, and fractions collected until their absorbances at 280 nm returned to 0. Peak fractions corresponding to purified IgG from three runs were pooled to yield 17.6 ml of a solution with an absorbance at 280 nm of 1.189, and a calculated protein concentration of 0.87 mg/ml. This solution was then brought to 50% (NH 4 ) 2 SO 4 saturation at 0° C. by the addition of 5.18 g of powdered (NH 4 ) 2 SO 4 with stirring over a 25 minute period, followed by an additional 25 minutes of stirring on ice. After centrifugation at 20,000 xg for 20 minutes, the resulting pellet was resuspended in 0.75 ml of 0.15M sodium phosphate, pH 7.5 to give a solution approximately 20 mg/ml IgG.
The conjugation procedure used is a modification of the procedure of Engvall (36), which is based upon the original procedure of Avrameas and Ternynck (37). Horseradish peroxidase (HRP, EC 1.11.1.7, Sigma lot 66F-9700-1) was dissolved in 0.2 ml 1.25% technical grade glutaraldehyde (Sigma, 25% glutaraldehyde diluted in 0.15M sodium phosphate, pH 7.2, 0.15M NaCl) in a glass test tube, and left at room temperature, in the dark, for 17 hours. The next day, the reaction mixture was diluted to 1.0 ml with 0.1M sodium carbonate buffer, pH 9.2, and dialyzed at 4° C. against two 1.0 L changes of this buffer. The purified IgG was also dialyzed at this time. After the dialysis, 0.25 ml of the IgG solution was added to the HRP solution (in a glass test tube), and allowed to incubate at room temperature for 15 hours. The next day, 0.2 ml of 0.2M lysine was added to the reaction mixture, shaken, and allowed to sit at 4° C. for 4 hours. The reaction mixture was then made 50% in glycerol, and stored as aliquots at -80° C.
Although avidin-biotin linked ELISAs have not yet been applied to insect contamination studies, the technology is widely used and the materials are readily available. Adaptation of the present ELISA to this format should prove fairly routine.
Avidin is a homotetrameric, 66,000 molecular weight glycoprotein which has a very strong, selective, and stable affinity for the small molecule biotin (38). Avidin is capable of binding four biotin molecules, and the dissociation constant (K d ) for the avidin-biotin complex is 10 -15 M (39); this is several orders of magnitude higher than the range of typical K d s for antigen-antibody complexes (10 -6 to 10 -11 M. Both biotin and avidin can be covalently linked to proteins, while maintaining the avidin-biotin interaction, as well as protein function. Not surprisingly, a large number of immunoassays have been developed which take advantage of these unique properties. Most of these immunoassays use a form of avidin known as streptavidin, isolated from Streptomyces avidinii. Streptavidin is a 60,000 molecular weight protein that lacks the glycoprotein moiety of avidin, this leads to a much reduced background (when compared to avidin) in several types of assays (40, 41).
There are two basic types of biotin-streptavidin immunoassays. In the first type of assay, a biotinylated antibody is used to detect the antigen of interest. The antigen may be either immobilized on some solid support (indirect ELISA) or bound to a capture antibody (sandwich ELISA). The biotinylated antibody bound to the antigen is then detected using an enzyme labeled streptavidin. Addition of substrate for the enzyme produces a detectable color proportional to the amount of antigen initially present. In the second type of assay, a "bridge" is formed between biotinylated antibody and biotinylated label by streptavidin. The initial procedure is as above, however, in place of labeled streptavidin, unconjugated streptavidin is added, followed by the addition of labeled biotin. Although this assay has an extra step, this extra step can lead to increased sensitivity in the detection of antigen.
The following literature citations are incorporated by reference in pertinent part herein for the reasons cited in the above text.
REFERENCES
1. Trauba (1981), Determination of Internal Insect Infestation in Wheat: Collaborative Study, J. Assoc. Off. Anal. Chem., 64(6):1408-1410
2. Parker et al (1982), Sampling, Inspection, and Grading of Grain, in Storage of Cereal Grains and Their Products, Chapter 1, pp. 1-35, American Association of Cereal Chemists.
3. Milner et al. (1950), Application of X-Ray Technique to the Detection of Internal Insect Infestation of Grain. J. Econ. Entomol., 43:933-935.
4. Street (1971), Nuclear Magnetic Resonance for Detecting Hidden Infestation in Stored Grains, J. Georgia Entomolog. Soc., 6(4):249:254.
5. Chambers et al. (1984), Nuclear Magnetic Resonance for Studying the Development and Detection of the Grain Weevil Sitophilus granarious (L.) (Coleoptera: Curculionidae) Within Wheat Kernels. Bull. Ent. Res., 74:707-724.
6. Chambers (1987), Recent Developments in Techniques for the Detection of Insect Pests of Stored Products. BCPC Mono. No. 37 Stored Products Pest Control. 151-166.
7. Adams et al. (1953), Aural Detection of Grain Infested Internally With Insects. Science, 118:163-164.
8. Street et al. (1976), CO 2 Analyzer Detects Insects Hidden in Foods. Fd. Engng., 48:94-95.
9. Ashman et al. (1969), An Instrument for detecting Insects Within Food Grains. Milling, 151:32-36.
10. Webb et al. (1988), A Computerized Acoustical Larval Detection System. Applied Engineering in Agriculture, 4:268-274.
11. Webb et al. (1988), Acoustical System to Detect Larvae in Infested Commodities. The Florida Entomologist, 71:492-504.
12. Vick et al. (1988), Sound Detection of Stored-Produce Insects That Feed Inside Kernels of Grain. J. Econ. Entomol., 81(5):1489-1493.
13. Monroe (1984), Enzyme Immunoassay, anal. Chem., 56(8):920A-931A.
14. Shoham et al. (1987), New Immunochemical Method for Rapid Detection of Human Chriogonadotropin in Urine, Clinical Chemistry, 33(6):800-802.
15. Klausner (1987), Immunoassays Flourish in New Markets, Bio/technology, 5(6):551-556.
16. Emerson et al. (1987) Molecular Genetics of Myosin, Ann. Rev. Biochem., 56:695-726.
17. Richards et al. (1946), Correlation Between the Possession of Chitinous Cuticle and Sensitivity to DDT. Biol. Bull. 90-107.
18. Prakasam et al. (1975), An Optimum pH for the Demonstration of Chitin in Periplaneta Americana Using Lugol's Iodine. Acta Histochem., 53:238-240.
19. Reissig et al. (1955), A Modified Colorimetric Method for the Estimation of N-Acetyl-Amino Sugars. J. Biol. Chem., 217:959-966.
20. Ride et al. (1971), A Chemical Method for Estimating Fusarium oxysporum f. lycopersici in infected tomato plants. Physiol Plant Pathol., 1:409-420.
21. Tsuji et al. (1969), Analytical Chemical Studies of Amino Sugars. Determination of Hexosamines Using 3-Methyl-2-Benzothiazolone Hydrazone Hydrochloride. Chem. Pharm. Bull., 17:1505-1510.
22. Wadsworth et al. (1984), Chitinolytic Activity of Commercially Available Beta-Glycosidase in "Chitin, Chitosan and Related Enzymes", J. P. Zikakis ed., Academic Press, 181-190.
23. Chaplain et al. (1966), The Mass of Myosin per Cross-bridge in Insect Fibrillar Flight Muscle, J. Mol. Biol., 21:275-280.
24. Woods et al. (1963), Studies on the Structure of Myosin in Solution, J. Biol. Chem., 238 (3):2374-2385.
25. Wang et al. (1984), Titin is an Extraordinarily Long, Flexible, and Slender Myofibrillar Protein, Proc. Natl. Acad. Sci. USA, 81:3685-3689.
26. Webber et al. (1969), The Reliability of Molecular Weight Determinations by Dodecyl Sulfate Polyacrylamide Gel Electrophoresis, J. Biol. Chem., 244(16):4406-4412.
27. Bradford (1976), A Rapid and Sensitive Method for the Quantitation of Microgram Quantities of Protein Using the Principle of Protein-Dye Binding, Anal. Biochem., 72:248-254.
28. Hunter et al. (1986), Immunological and Biosynthetic Studies on the Mammalian 2-oxoglutarate Dehydrogenase Multienzyme Complex, Europ. J. Biochem., 155:103-109.
29. Hurn et al. (198), Production of Reagent Antibodies, Methods in Enzymology, 70:104-102.
30. Browning et al. (1987), Identification of Two Messenger RNA Cap Binding Proteins in Wheat Germ, J. Biol. Chem., 262(23):1128-11232.
31. Levine et al. (1982), Preparation and Assay of Paramyosin, Methods in Enzymology, 85(16):149-164.
32. Wang et al. (1984), Titin is an Extraordinarily Long, Flexible, and Slender Myofibrillar Protein, Proc. Natl. Acad. Sci. USA, 81:3685-3689.
33. Monroe et al. (1985), The Solid Phase Enzyme Linked Immunospot Assay: Current and Potential Applications, BioTechniques May/Jun. 222-229.
34. Bahr et al. (1980), Immunology, 41:865-873.
35. Ey (1978), Isolation of Pure IgG 1 , IgG 2a , and IgG 2b Immunoglobulins from Mouse Serum Using Protein-A Sepharose, Immunochem., 15:429-436.
36. Engvall (1980), Enzyme Immunoassay ELISA and EMIT, Methods in Enzymology, 70:418-439.
37. Avrameas et al. (1971), Peroxidase labeled antibody and Fab conjugates with enhanced intracellular penetration, Immunochem., 8:1175-1179.
38. Green et al. (1975), In: Advances in Protein Chemistry, C. B. Anfinsen, ed., 29:85.
39. Green (1963), Avidin, Biochem. J., 89:593-620.
40. Gardner (1983), Biotechniques, 1:39.
41. Haeuptle et al., (1983), Binding Sites for Lactogenic and Somatogenic Hormones from Rabbit Mammary Gland and Liver, J. Biol. Chem., 258:305. | The present invention involves approaches to the detection of insect contamination of foodstuffs such as grain, for example. These approaches involve the detection of biological substances characteristic of insects. One such approach is an assay for the insect exoskeleton material, chitin. This test is particularly suited to the detection of live or dead specimens of the adult or egg stages of insects and for insect parts. Another type of assay uses an immunological approach to the detection and quantitation of an insect-specific protein such as the insect muscle protein, myosin or components thereof, for example. This type of test is well suited for detecting all stages of insect development from egg to adult, whether live or dead. It should also provide an assay system that correlates well to the current insect fragment assay. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
Not applicable, or none.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not applicable, or none.
REFERENCE TO SEQUENCE LISTING, A TABLE, OR A COMPUTER PROGRAM LISTING COMPACT DISK APPENDIX
Not applicable, or none.
BACKGROUND OF THE INVENTION
This invention relates, generally, to improvements in electrolytic cells that generate chlorine gas and caustic solutions and delivers those products to a drinking water supply system, wastewater treatment system, industrial processing system, or a swimming pool. More particularly, it relates to a portable chlorine generator that can be used in the field to generate chlorine from common salt to sanitize or oxidize water.
U.S. Pat. No. 6,368,474 (2002); U.S. Pat. No. 5,779,874 (1998); U.S. Pat. No. 5,133,848 (1992); U.S. Pat. No. 4,724,059 (1988) and the references to record therein are believed to represent the most relevant prior art to this disclosure.
Chlor-alkali cells provide an electromotive force to split the ionic bond between sodium and chlorine elements of ordinary sodium chloride (table salt). Chlorine is used as a disinfectant in water, wastewater, and swimming pool applications. Chlorine is also used as an oxidant in water, wastewater, and industrial treatment processes. The sodium produced from the process combines with water to form sodium hydroxide (caustic) which is used as a disinfectant and pH control chemical in water, wastewater and swimming pool applications. Caustic is also used as a cleansing chemical agent in several processes.
The chlor-alkali process in its simplest form, employs the use of an anode electrode, cathode electrode, a membrane placed between the two electrodes, and solutions called electrolytes. The process employs an electrical current within the electrolytes to generate the products of the process, mainly chlorine gas and sodium hydroxide (caustic soda). The components of the chlor-alkali process are contained within a cell. The cell in conjunction with the membrane provide isolation of the electrolytes generated at each electrode. The cell also provides isolation of the of the chlor-alkali process with the outside environment. The necessity of the cell and membrane to isolate the electrolytes is discussed extensively in the prior art. The necessity of the cell to isolate the chlor-alkali process from the environment is obvious since the products of the process are hazardous to the humans and the surrounding environment.
The electrolyte at the anode is generally referred as the anolyte, and is primarily water and salt producing a saturated saltwater brine solution. The electrolyte at the cathode is generally referred as the catholyte, and is primarily a solution of sodium hydroxide, or caustic soda. The need to isolate the electrolytes with a membrane are primarily for process control and efficiency.
The claims in the prior art describe apparatuses or methods utilizing numerous parts to generate chlorine from salt. Collier (U.S. Pat. No. 4,724,059), Meyers (U.S. Pat. No. 5,133,848) and Wilkins (U.S. Pat. No. 6,368,474) describe cells having two upward extending liquid holders that contain the process electrolytes. The Wilkins cell describes the use to sight tubes to view the electrolytes and a handle to facilitate the system mobility. Although these apparatuses illustrate portability, the inventions also illustrates numerous parts that utilize specialized molded or tooled components. The applicants U.S. Pat. No. 5,779,874 illustrates a simplified single wedge flanged cell system that contains electrolytes for chlorine production. Salt can be added to the cell through the anode opening and independently operated without an external brine supply system. This configuration is certainly applicable for portable and small chlorine applications; however, the cell requires anode removal to re-supply salt to the cell.
A need therefore exists for a portable chlorination system that is simple to manufacture with minimal parts that can be purchased without expensive tooling. Such system will be available to the consumer at a reduced capital cost with significant savings in operation and maintenance costs when compared to other chlorination systems. A simplified chlorine generator will also allow development and use in remote third world areas that certainly need inexpensive yet reliable chlorination devices.
BRIEF SUMMARY OF THE INVENTION
The present invention employs a chlor-alkali cell with one cell end connected to an anolyte compartment and the opposite cell end connected to the catholyte compartment. The cell and electrolyte compartments are constructed of typical pipe fittings of suitable material available from any hardware or plumbing supply store. The cell compartments shall allow controlled access from the exterior environment to allow the addition of salt and water for the process operation. The compartment can be of any size necessary to achieve the desired level of system portability. The power system may include a power controller consisting of a power cord, dimmer switch, and a power plug receptacle. With the power controller plugged into any 120 VAC power outlet, the operator can utilize any power supply source (i.e. battery charger) plugged into the power controller where the power supply amperage is controlled by adjusting the dimmer switch. The active power supply connected to the electrodes extending from the exterior of the electrolyte compartments generate chlorine gas that is swept from the anode compartment through a vacuum system connected to a fitting at the top of the compartment lid.
The present invention eliminates the various complicated means described in the earlier patents of apparatus construction. The present invention also allows the use of any direct current power supply to generate chlorine gas.
It is therefore understood that the primary objective of this invention is to provide a chlorine generator that is economical to construct and simple to install and maintain.
Accordingly, several objects and advantages of my invention are:
(a) to provide a cell having no specialized frame or divider system that requires added tooling or specialized training to install and operate; (b) to provide cell compartments of sufficient size to house the salt and electrolytes; (c) to design cell compartments with readily available components; (d) to provide a power control system that allows the operator to utilize any direct current (DC) power supply on the chlorination system; (e) to design a power control system that allows the operator to adjust the chlorine production output to the desired level;
Further objects and advantages will become apparent from a consideration of the ensuing description and drawings.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
For a fuller understanding of the nature and objects of the invention, reference should be made to the following detailed description, taken in consideration with the accompanying drawings in which:
FIG. 1 is an isometric representation of the invention showing a power control system and direct current (DC) power source with electrical conduits connected to electrodes of a chlorine generator. FIG. 1 illustrates a chlorine generator completely assembled and ready for operation.
FIG. 2 is an isometric representation of the invention showing all the components of the chlorine generator. FIG. 2 illustrates the order at which the cell compartments are assembled.
FIG. 3 is a cross-section of the chlorine generator showing the position of interior components.
Numerical representations shown within the figures outlined above are referenced by the following components:
10 cell
20 anode compartment
30 cathode compartment
21 anode flange
31 cathode flange
22 anode opening
32 cathode opening
23 anode compartment opening
33 cathode compartment opening
24 anode lid
34 cathode lid
25 anolyte container
35 catholyte container
26 anode stem opening
36 cathode stem opening
27 anode compartment connector
37 cathode compartment connector
28 anode compartment base
38 cathode compartment base
29 anolyte port
39 catholyte port
40 cell compression collar
41 exterior compressive wedge
42 interior compressive wedge
44 compression collar opening
45 compression collar flange
50 membrane
60 anode seal
61 cathode seal
62 flange groove
63 anode stem seal
65 cathode stem seal
70 anode
80 cathode
71 anode stem
81 cathode stem
72 anode face
82 cathode face
90 electrical conduit
91 power supply
92 power control
94 plug receptacle
95 dimmer switch
96 power cord
99 alternating current (AC) power
supply
DETAILED DESCRIPTION OF THE INVENTION
The configuration of the invention can partake several forms. It is the intention of this narrative to describe in detail the invention for a chlor-alkali system that produces 0.01-1.0 kilograms (0.02-2.2 pounds) of chlorine gas per day. Illustrations of this type of system are shown in FIGS. 1 , 2 , and 3 .
FIG. 1 is an isometric representation of the invention in its assembled form. As shown in FIG. 1 , the invention is comprised of a cell 10 divided into an anode compartment 20 and a cathode compartment 30 . Continuity or attachment of anode compartment 20 with cathode compartment 30 is provided by a cell compression collar 40 .
Cell 10 is made of a rigid, non-electrically conductive material such as fiberglass, polyvinyl chloride (PVC) plastic, chlorinated polyvinyl chloride (CPVC) plastic, polyvinylidene fluoride (PVDF) plastic, polytetrafluoroethylene (PTFE) plastic or other plastics that are chemically resistant to the solutions and gases contained within cell 10 . More specifically, the material of anode compartment 20 must be chemically resistant to chlorine gas, sodium chloride, sodium chloride brine, and anolyte contained in anode compartment 20 . The material of cathode compartment 30 must be chemically resistant to hydrogen gas, sodium hydroxide, and a catholyte contained in cathode compartment 30 .
FIG. 2 best illustrates the individual features of cell 10 . As shown in FIG. 2 , cell 10 may have a cylindrical or tubular shape with attached tubular fittings, but can also have a shape in the configuration of a multi-sided polygon. Anode compartment 20 has an anode opening 22 to allow placement of an anode 70 positioned within anode compartment 20 . Anode 70 has an anode stem 71 connected perpendicular to an anode face 72 . The inside dimensions of anode compartment 20 at anode opening 22 must be slightly larger than the dimensions of anode face 72 . Cathode compartment 30 has a cathode opening 32 to allow placement of a cathode 80 positioned within cathode compartment 30 . Cathode 80 has a cathode stem 81 connected perpendicular to a cathode face 82 . The inside dimensions of cathode compartment 30 at cathode opening 32 must be slightly larger than the dimensions of cathode face 82 . The junction of anode compartment 20 and cathode compartment 30 of cell 10 includes an anode flange 21 and a cathode flange 31 . As shown by FIG. 2 , anode flange 21 and cathode flange 31 are circular in configuration. Size and shape of anode flange 21 and cathode flange 31 are primarily dependent on the dimensions of cell compressive collar 40 .
Anode compartment 20 and cathode compartment 30 are hydraulically isolated from the outside environment by an anode seal 60 and a cathode seal 61 . Anode seal 60 and cathode seal 61 are made of flexible synthetic material of variable thickness and shape having elastic properties including butyl rubber; ethylene polypropylene rubber such as EPDM, EPT, EPR; chloroprene rubber such as Norprene®; or fluorine rubber such as Viton®. The material for anode seal 60 should be chemically resistant to the anolyte contained in anode compartment 20 , and the material for cathode seal 61 should be chemically resistant to the catholyte in cathode compartment 30 . Anode seal 60 and cathode seal 61 further having a hardness less than 90 durometer, preferably less than 70 durometer. In this particular example, cathode seal 61 consists of a 3 millimeter (⅛ inch) thick flat EPDM rubber sheet having the same dimensions of cathode flange 31 . Anode seal 60 consists of a 6.35 millimeter (¼ inch) diameter Viton® rubber o-ring material in communication with a flange groove 62 , or depression encompassing the surface of anode flange 21 .
Anode compartment 20 is in open communication with cathode compartment 30 through anode opening 22 encompassed by anode flange 21 and cathode opening 32 encompassed by cathode flange 31 . Anode compartment 20 is hydraulically isolated from cathode compartment 30 by a membrane 50 . Membrane 50 is a cation selective permionic membrane typically fabricated of a fluorocarbon resin containing active acid groups such as carboxylic acid sulfonic acid groups, derivatives of these groups, or mixture of two or more of those groups. Membrane 50 may include a PTFE reinforcement mesh to add structural rigidity. Thus membrane 50 provides electrically conductive communication between anode compartment 20 and cathode compartment 30 . The dimensions of membrane 50 encompass the area between the outside edge of anode gasket 60 and the outer edge circumference of anode flange 21 . In this particular example, membrane 50 has an approximate diameter of 13 centimeters (5 inches).
A wedge or threaded configuration cell compression collar 40 uniformly compresses membrane 50 between anode seal 60 fitted within flange groove 62 on anode flange 21 and cathode seal 61 on cathode flange 31 . Cell compression collar 40 is made of a rigid material such as fiberglass, polyvinyl chloride (PVC) plastic, chlorinated polyvinyl chloride (CPVC) plastic, polyvinylidene fluoride (PVDF) plastic, polytetrafluoroethylene (PTFE) plastic, high density polyethylene (HDPE) plastic, or various types of metal including stainless steel, aluminum, and titanium. Cell compressive collar 40 encompasses anode flange 21 and cathode flange 31 .
FIG. 2 illustrates a 5, 7.6, or 10 centimeter (2, 3, or 4 inch) diameter union pipe fitting having an exterior compression wedge 41 or thread firmly attached or contiguous with the exterior circumference of cathode flange 31 , and an interior compression wedge 42 or thread firmly attached or contiguous with the interior of cell compression collar 40 . A compression collar opening 44 , defined by the interior circumference of a compression collar flange 45 on cell compression collar 40 , must be larger in diameter than the exterior dimensions of cell 10 at the junction of anode flange 21 and smaller in diameter that the outside circumference of anode flange 21 . Cell compression collar 40 is rotative having interior compression wedge 42 in symmetrical connective communication with exterior compression wedge 41 . The interior surface of compression collar flange 45 is in symmetrical communication with the back exterior surface of anode flange 21 where the surface of compression collar flange 45 meets the back surface of anode flange 21 when interior compression wedge 42 is fully engaged within exterior compression wedge 41 .
Anode flange 21 is hydraulically connected to an anolyte container 25 by an anode compartment connector 27 . Connection of anode compartment connector 27 to anode flange 21 and anolyte container 25 is by wedge communication, tapered wedge communication, glue cementing, or material fusion processes. Anolyte container 25 is connected to an anode compartment base 28 providing closed communication to the exterior environment. Connection of anolyte container 25 to anode compartment base 28 is by wedge communication, tapered wedge communication, glue cementing, or material fusion processes. Anolyte container 25 is connected to an anode lid 24 providing controlled closed communication to the exterior environment. Connection of anolyte container 25 to anode lid 24 is by tapered wedge communication or wedge communication providing access to anolyte container 25 interior. Anode lid 24 includes an anolyte port 29 providing controlled communication between the interior anode compartment 20 and other external system processes. Additional tubular or pipe fittings can be added to anolyte container 25 on either the bottom or the top, or both for increased anolyte volume or positional stability.
Cathode flange 31 is hydraulically connected to a catholyte container 35 by a cathode compartment connector 37 . Connection of cathode compartment connector 37 to cathode flange 31 and catholyte container 35 is by wedge communication, tapered wedge communication, glue cementing, or material fusion processes. Catholyte container 35 is connected to a cathode compartment base 38 providing closed communication to the exterior environment. Connection of catholyte container 35 to cathode compartment base 38 is by wedge communication, tapered wedge communication, glue cementing, or material fusion processes. Catholyte container 35 is connected to a cathode lid 34 providing controlled closed communication to the exterior environment. Connection of catholyte container 35 to cathode lid 34 is by tapered wedge communication or wedge communication providing access to catholyte container 35 interior. Cathode lid 34 includes a catholyte port 39 providing controlled communication between the interior cathode compartment 30 and other external system processes. Additional tubular or pipe fittings can be added to catholyte container 35 on either the bottom or the top, or both for increased catholyte volume or positional stability.
FIG. 3 illustrates anode 70 positioned within anode compartment 20 through anode opening 22 defined by the interior dimension of anode flange 21 . Anode 70 is made of an electrically conductive material that is chemically resistant to the chlorine gas and anolyte in anode compartment 20 . Such material includes graphite carbon, or titanium, zirconium, niobium, tungsten or tantalum having a coating of an electrically conductive electrocatalytically material of platinum rhodium, iridium, ruthenium, osmium or palladium, and/or oxide of one or more of these metals. One common example is a platinum coated titanium anode with a solid or mesh form. Cell compression collar 40 consisting of a 7.6 centimeter (3 inch) diameter CPVC union pipe fitting, anode compartment 20 consisting of a 7.6 centimeter (3 inch) diameter schedule 80 CPVC pipe, requires a 7 centimeter (2.75 inch) diameter anode face 72 which produces from 0.01-1.0 kilograms (0.02-2.2 pounds) of chlorine gas per cell per day. Anode 70 further having anode stem 71 of same material that is rigidly attached or welded to anode 70 and extending horizontally out of anode compartment 20 through an anode stem opening 26 at the outward side of anode compartment 20 opposite of anode opening 22 . Anode stem 71 may be a threaded stem 6.35 millimeter (¼ inch) in diameter and 23-24 centimeters (9 inches) long, welded perpendicular at right angles to the center inside face of anode face 72 .
Anode stem opening 26 is environmentally sealed by an anode stem seal 63 between anode stem 71 and anode compartment 20 at anode stem opening 26 . Anode stem seal 63 is made of flexible synthetic material of variable thickness and shape having elastic properties including butyl rubber; ethylene polypropylene rubber such as EPDM, EPT, EPR; chloroprene rubber such as Norprene®; or fluorine rubber such as Viton®. More specifically, the material for anode stem seal 63 should be chemically resistant to the chlorine gas and anolyte contained in anode compartment 20 , and have a hardness less than 90 durometer, preferably less than 70 durometer. In this particular example, anode stem seal 63 is a tubular material encompassing anode stem 71 . Anode stem seal 63 having a hollow interior diameter similar to, or slightly smaller than anode stem 71 diameter. Anode stem seal 63 exterior diameter is slightly larger than anode stem opening 26 diameter.
FIG. 3 further illustrates cathode 80 positioned within cathode compartment 30 through cathode opening 32 defined by the interior dimension of cathode flange 31 . Cathode 80 is made of an electrically conductive material that is chemically resistant to the hydrogen gas and catholyte in cathode compartment 30 . Such material includes titanium, iron or steel, or of other suitable metal such as nickel. The size of cathode 80 must be slightly smaller that the dimensions of cathode opening 32 , and preferably the same size of anode 70 . Cathode 80 further having a cathode stem 81 of same material that is rigidly attached or welded to cathode face 82 and extending horizontally out of cathode compartment 30 through a cathode stem opening 36 at the end of cathode compartment 30 opposite of cathode opening 32 . Cathode stem 81 may be a threaded stem 9-10 millimeter (⅜ inch) in diameter and 23-24 centimeters (9 inches) long, welded perpendicular at right angles to the center inside face of cathode face 82 .
Cathode stem opening 36 is environmentally sealed by compression of a cathode stem seal 65 between cathode stem 81 and cathode compartment 30 at cathode stem opening 36 . Cathode stem seal 65 is made of flexible synthetic material of variable thickness and shape having elastic properties including butyl rubber; ethylene polypropylene rubber such as EPDM, EPT, EPR; or chloroprene rubber such as Norprene®. More specifically, the material for cathode stem seal 65 should be chemically resistant to the hydrogen gas and catholyte contained in cathode compartment 30 , and having a hardness of less than 90 durometer, preferably less than 70 durometer. In this particular example, cathode stem seal 65 is a tubular material encompassing cathode stem 81 . Cathode stem seal 65 having a hollow interior diameter similar to, or slightly smaller than cathode stem 81 diameter. Cathode stem seal 65 exterior diameter is slightly larger than cathode stem opening 36 diameter.
As shown in FIG. 1 , anode stem 71 and cathode stem 81 portions that exit cell 10 exterior are independently connected by an electrical conduit 90 to the output of a power supply 91 . Electrical conduit 90 is a copper wire or cable of sufficient size to transmit the direct current amperage loading from power supply 91 to cell 10 . In this particular example, electrical conduit 90 is a # 10 AWG size stranded copper wire capable of transmitting 15-30 direct current amperes from power supply 91 to cell 10 .
Power supply 91 may be electrically connected to a power control 92 having a plug receptacle 94 , a dimmer switch 95 and a power cord 96 . Power cord 96 is electrically connected in series to dimmer switch 95 further connected in series to plug receptacle 94 . Power cord 96 is electrically connected to an alternating current power supply 99 . In this particular example, alternating current power supply 99 is a 120 volt alternating current (VAC) electrical energy source. Power cord 96 is a three wire # 16 AWG size stranded copper wire capable of transmitting 10 alternating current amperes from alternating current power supply 99 to power control 92 . Dimmer switch 95 is an SCR switch or variable solid state voltage regulator switch rated at 300 watts or more. Plug receptacle 94 is a three prong receptacle capable of receiving a typical 120 VAC power cord plug and capable of transmitting 15 amperes of alternating current.
Operation of Invention
It should be understood that FIG. 2 depicts cell 10 in the pre-assembly mode. The illustration of the pre-assembly mode depicts the various elements of cell 10 prior to assembly of cell 10 . It should be further understood that FIGS. 1 and 3 depict cell 10 in the assembled mode. The illustration of the assembled mode depicts the configuration of cell 10 ready for operation.
To establish an operable cell 10 as shown in FIG. 1 , the components of cell 10 must be assembled as illustrated in FIG. 2 . To assemble anode compartment 20 , anode stem seal 63 is positioned within anode stem opening 26 of anode compartment 20 . Anode 70 is then placed within anode compartment 20 through anode opening 22 . Anode stem 71 is inserted through the hollow tubular opening of anode stem seal 63 providing a compressive seal between anode stem 71 and anode compartment 20 compresses at anode stem opening 26 . Anode 70 is positioned directly behind anode opening 22 with anode stem 71 extending horizontally outward through anode stem opening 26 .
The assembly of cathode compartment 30 follows the same procedures as described in the assembly of anode compartment 20 . Nonetheless, cathode stem seal 65 is positioned within cathode stem opening 36 of cathode compartment 30 . Cathode 80 is then placed within cathode compartment 30 through cathode opening 32 . Cathode stem 81 is inserted through the hollow tubular opening of cathode stem seal 65 providing a compressive seal between cathode stem 81 and cathode compartment 30 compresses at cathode stem opening 36 . Cathode 80 is positioned directly behind cathode opening 32 with cathode stem 81 extending horizontally outward through cathode stem opening 36 .
Following installation of anode 70 in anode compartment 20 and cathode 80 in cathode compartment 30 , membrane 50 is positioned between anode seal 60 on anode flange 21 and cathode seal 61 on cathode flange 31 , providing electrically conductive communication between anode opening 22 and cathode opening 32 . With cell 10 remaining fixed in position, cell compression collar 40 having interior compression wedge 42 is rotated onto exterior compression wedge 41 which is rigidly attached or contiguous with the exterior circumference of cathode flange 31 . Interior compression wedge 42 being in connective communication with exterior compression wedge 41 allows compression collar flange 45 to uniformly seat or meet with the exterior back surface of anode flange 21 . When the interior surface of compression collar 45 meets the exterior back surface of anode flange 21 , the wedging or squeezing developed by the added torque or rotational force applied to cell compression collar 40 between interior compressive wedge 42 and exterior compressive wedge 41 redistributes the torque or rotational force to a compression force between anode flange 21 and cathode flange 31 . The compressive force is applied symmetrically along anode seal 60 and cathode seal 61 , thus sealing the interior of cell 10 from the outside environment. Frictional properties between the surface of interior compressive wedge 42 and the surface of exterior compressive wedge 41 of cell compression collar 40 maintains symmetrical compression of anode seal 60 on anode flange 21 and cathode seal 61 on cathode flange 31 when the torque or rotational force is removed.
Salt and water added to anode compartment 20 provide the means for anolyte solution. Water or sodium hydroxide added to cathode compartment 30 provide means for catholyte solution. Electrical conduit 90 is then connected to the environmentally exposed portion of anode stem 71 and cathode stem 81 . Cell 10 is further connected to any other necessary appurtenances including direct current power supply 91 and perhaps power control 92 to allow proper operation of the chlor-alkali process. Chlorine gas generated from anolyte compartment 20 exits through anolyte port 29 to the desired chlorine application. Hydrogen gas generated from the catholyte compartment 30 exits through catholyte port 39 to the atmosphere.
Routine maintenance of cell 10 requires the addition of salt and water to the anode compartment 20 , addition of dilution water to cathode compartment 30 , and removal of membrane 50 for cleaning, treatment, or replacement. Removal of membrane 50 is accomplished by applying a torque or rotational force to cell compression collar 40 in the opposite direction stipulated in the assembly mode. The amount of torque or rotational force required to release cell 10 from cell compression collar 40 must exceed the static frictional force existing between the surface of interior compressive wedge 42 and the surface of exterior compressive wedge 41 of cell compression collar 40 . Addition of salt and water to anode compartment 20 is accomplished by removal of anode lid 24 to access the interior of anode compartment 20 . Anode lid 24 can be a clear plastic or glass material to allow for visual observation of anode compartment 20 interior. A hydrometer used for testing batteries can be used to measure the density of sodium hydroxide in cathode compartment 30 . Dilution water is manually added to cathode compartment 30 when the excessive upper density limit is exceeded. The excess sodium hydroxide removed from cathode compartment 30 is disposed down a drain, kept for future cell operation, or used and needed in other treatment processes.
Conclusions, Ramifications, and Scope of Invention
As with the prior art, the novel apparatus depicted above provides a simple means to install a membrane that hydraulically isolates the anode compartment from the cathode compartment of a typical chlor-alkali cell. In addition, this invention is simple and economical to assemble from readily available components found in many areas of the world. Furthermore, the apparatus allows the addition of salt and water to the cell without removal of the electrodes. Certainly, the size of the system promotes portability without the need for a handle; however additional tubing or piping can be added to increase the cell size as desired. Lastly, the power control allows the operator us adjust any power supply to the optimum level of energy providing a range of chlorine needs with one single cell.
It will thus be seen that the objects set forth above, and those made apparent from the foregoing description, are efficiently attained and since certain changes may be made in the above construction without departure from the scope of the invention, it is intended that all matters contained in the foregoing description or shown in the accompanying shall be interpreted as illustrative and not in a limiting sense.
It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described, and all statements of the scope of the invention which, as a matter of language, might be said to fall there between. | A chlorine generator cell ( 10 ) contains components that require physical isolation between the anode compartment ( 20 ), cathode compartment ( 30 ), and outside environment. The cell ( 10 ) also contains a membrane ( 50 ) that provides selective electrical conductivity between the anode compartment ( 20 ) and cathode compartment ( 30 ). The cell ( 10 ) consists of a series of pipe fittings that allow access to the interior of cell ( 10 ) for placement of water and salt to generate chlorine. The anode stem ( 71 ) and cathode stem ( 81 ) located outside of cell ( 10 ) are connected to a power supply ( 91 ). Power supply ( 91 ) may be further connected to a power controller ( 92 ) that allows for adjustment of the energy output of power supply ( 91 ) to the optimum energy level, thus the desired chlorine output. This invention provides a chlorine generator that is portable, yet is allows for expanded size with additional pipe fittings as needed. Furthermore, this invention allows multiple to infinite chlorine output levels with a single cell ( 10 ). | 2 |
RELATED APPLICATION
This application claims priority from provisional application Ser. No. 60/827,552, which was filed on Sep. 29, 2006, and which is incorporated herein by reference in its entirety.
FIELD OF THE INVENTION
The present invention relates to the field of drug testing, and, more particularly, to a method for detecting a binding interaction between a drug and a cell membrane protein target.
BACKGROUND OF THE INVENTION
Structure-function studies of proteins impose two major requirements on biophysical spectroscopic methods. First, to succeed in such studies, a spectroscopic method should be capable of providing atomic-scale structural data with minimal perturbation to the system. Second, the protein should be maintained in a functionally relevant conformational state. Ideally, one would like to observe detailed molecular structure while the protein progresses through conformational states associated with normal function.
Although modern high-resolution NMR spectroscopy offers unique opportunities for structure-function studies of many water-soluble proteins, membrane proteins are generally less amendable to solution NMR methods. Molecular tumbling of proteins in lipid bilayer systems is insufficient to average out anisotropic magnetic interactions, thus causing broad NMR lines that lead to inevitable loss of resolution and sensitivity. One way to approach the line width problem is to solubilize membrane proteins in mixed detergent micelles that form a shell around the hydrophobic portion of the protein. These detergent-protein complexes may tumble rapidly enough in solution to produce narrow, motionally averaged NMR resonances.
Unfortunately, surrounding some proteins with detergent molecules is known to destabilize functional conformational states and/or perturb the membrane protein tertiary structure (1). There is also growing evidence that many membrane proteins adopt functionally active conformational states only when embedded in or interacting with lipid bilayers of specific composition representative of the native environment (2).
Alternatively, membrane proteins can be studied by solid-state NMR with spectral resolution improved through macroscopic alignment of the surrounding lipid bilayers with respect to the magnetic field axis. Such alignment results in all proteins in the sample having the same polar angle with respect to the bilayer normal perpendicular to the field, therefore decreasing anisotropic line shape contributions. However, longitudinal orientation of the protein in this spherical coordinate system defined by the bilayer normal remains undetermined, and the anisotropy resulting from observations over the longitudinal angle can still lead to line broadening. This remaining anisotropy can be averaged by rapid rotational diffusion of the protein about the lipid bilayer normal (3). Thus, the latter condition constitutes another essential requirement for achieving the best spectral resolution for macroscopically aligned membrane proteins in which nuclear chemical shift tensors are not uniformly aligned with B0.
Generally, lipid bilayer samples are aligned either mechanically by assembling bilayers on planar solid surfaces such as glass (4) or magnetically by forces that arise in external magnetic field for discoidal bilayered micelles (also called bicelles) with sufficient degree of anisotropic magnetic susceptibility (5, 6).
Bicelles can be prepared by mixing long-chain phospholipids such as DMPC (1,2-dimyristoyl-sn-glycero-3-phosphocholine) with a short-chain DHPC (1,2-dihexanoyl-snglycero-3-phosphocholine) in a molar ratio greater than approximately 2.5. In these bicelles, DMPC molecules form near planar bilayers that are capped by short-chain DHPC lipids. The negative sign of the bicelles' magnetic susceptibility tensor forces them to align with the bilayer surface parallel to the direction of the magnetic field. Addition of a few mol percent (with respect to the lipids) of certain lanthanide ions flips the bicelle orientation by 90° (7). For solid-state NMR experiments with membrane proteins, the bicelle magnetic field alignment method offers several important advantages including ease of sample preparation, full hydration of lipid bilayers, and long (>1 year) shelf life of biologically stable samples (8). Although several other lipid compositions for bicelles have been reported in the literature, including mixtures that maintain alignment at both acidic and basic pH values (9) and extended temperature range (10), the choice of lipid composition for anisotropic bicelles that would undergo magnetic field alignment remains limited in comparison with the mechanical (or substrate) alignment method. The latter can be successfully employed for bilayers composed from various types of lipids and under an extended range of external conditions such as temperature, ionic strength, pH, etc. (4, 11-13). Therefore, the mechanical alignment method is generally more applicable and is practiced more often in studies of membrane proteins (14, 15).
One significant drawback of the substrate-alignment method derives from the somewhat limited ability to modify the sample hydration, pH, ionic strength, and concentration of molecules in the aqueous phase. Consequently, it is virtually impossible to expose the same sample, without lengthy sample regeneration and realignment, to a variety of water-soluble agents that could be used to trigger changes in membrane protein conformation or function. These limitations of the planar substrate-aligned lipid bilayer samples prevent many applications of high-resolution solid-state NMR methods for detailed structure-function studies of membrane proteins.
Nanopore-supported lipid nanotube arrays introduced recently (16) provide an attractive way for aligning membrane protein samples for solid-state NMR experiments (17, 18). In brief, it was shown that these macroscopically aligned nano-tubular bilayers are formed by lipid self-assembly inside nano-porous anodic aluminum oxide (AAO) substrates. FIG. 1 shows a cartoon of a single lipid bilayer that is spreading along a nanopore. AAO substrates have aligned through-film nanoporous channels with exceptionally high density. Examination of typical commercial AAO membranes from Whatman International (Maidstone, UK) with scanning electron microscopy (SEM) have shown that the pore density is at least 109 pores/cm2 with an average pore diameter of 177±20 nm (Alaouie, unpublished results). Thus, for 60 μm thick substrate, the total surface area of the nanoporous channels is 334±38 cm 2 for each 1×1×0.006 cm 3 AAO strip. Elemental chemical analysis has shown that on average up to four lipid nanotubular bilayers can be deposited into each of these AAO nanopores (19). Then such a deposition would provide approximately the same lipid bilayer surface area as depositing 1300 lipid bilayers on top of a 1 cm 2 glass slide. Consequently, by stacking a few tens of AAO strips, one can achieve similar lipid volumes in NMR experiments as in the conventional glass plate method. This was indeed confirmed directly by NMR experiments that demonstrated similar signal/noise ratio for AAO-supported and glass-aligned transmembrane domain of the M2 protein of influenza A virus (17).
Recent studies have shown that the new AAO-supported bilayers retain many biophysical properties of unsupported lipid vesicles (19, 20), and they are suitable for aligning membrane proteins for high-resolution multidimensional solid-state NMR studies (17). Detailed NMR (17, 18, 21, 22) and DSC (19, 20) studies provided further characterization of the biophysical properties of such nanotubular bilayers. Specifically, 31 P NMR studies of POPC (1-palmitoyl-2-oleoyl-snglycero-3 phosphocholine) bilayers absorbed into AAO nanopores indicated that some portions of the bilayer surface were inaccessible to Pr 3+ shift reagent when the bilayer was maintained above the main phase transition temperature. Thus, it was concluded that under the latter conditions the ends of the bilayer tubules must be well sealed against the pore such that the ions cannot penetrate into the water underneath the bilayers (21).
Here, we have reexamined the nanotubular bilayer surface accessibility using Mn 2+ ions as paramagnetic broadening agents. We demonstrate that, under typical conditions of sample preparation (using DMPC lipids instead of POPC lipids) and handling above and below the main phase transition temperature, both leaflets of nanotubular bilayers are fully accessible to this divalent ion without compromising the macroscopic lipid alignment. Moreover, we demonstrate that the broadening of the 31 P resonances is reversible by a gentle treatment of the AAO stack with the chelating agent EDTA (ethylenediaminetetraacetic acid) followed by a straightforward buffer exchange at temperatures above the main phase transition. This indicates that lipid nano-tube arrays can be prepared with the bilayer surfaces fully accessible to water-soluble molecules. Thus, the high hydration levels of these structures as well as pH and desirable ion and/or drug concentrations can be easily maintained and modified. We are particularly interested in exploring these unique features that permit solvent flow through lipid nano-tube arrays for structure-function studies of membrane proteins by solid-state NMR spectroscopy. Here, we present a demonstration of such experiments at high magnetic field (19.6 T) using 17 O NMR anisotropic chemical shift effects of ion binding to the gramicidin A channel.
The molecular mechanism of ion selectivity in K + channels is based on the polypeptide backbone carbonyls (23, 24) that provide solvation for K + on binding. The same fundamental ion-binding interactions are known to contribute to the ion conductance mechanism of other ion transporters including the dimeric gramicidin A (gA) pore, which functions as a monovalent cation-selective channel (25). Gramicidin A is a 15-residue polypeptide with an alternating sequence of D- and L-amino acids: HCO-L-Val 1 -Gly 2 -L-Ala 3 -D-Leu 4 -L-Ala 5 -D-Val 6 -L-Val 7 -D-Val 8 -L-Trp 9 -D-Leu 10 -L-Trp 11 -D-Leu 12 -L-Trp 13 -D-Leu 14 -L-Trp 15 -NHCH 2 CH 2 OH (25). In bilayers formed from lipids with fatty acyl chain lengths matching the hydrophobic dimension of the right-handed b-helix, this polypeptide forms a dimer with a 4.5-Å pore accommodating ions and a single file of water molecules (26, 27). Recent NMR studies carried out with gA uniformly aligned in DMPC bilayers using the glass plate method concluded that the carbonyl oxygen of D-Leu 10 is one of the three carbonyls involved in the ion-binding site at each end of the channel (28, 29).
Specifically, significant perturbation of 17 O anisotropic chemical shift was observed when the gA binding sites were predominantly occupied with two potassium cations (29, 30). Moreover, it was determined that binding of other ions also affects the 17 O NMR chemical shift and that this parameter is a significantly more sensitive indicator for binding events than the 15 N chemical shift typically employed in such studies (29) (E. Y. Chekmenev, L. N. Miller, P. L. Gor'kov, Z. Gan, and T. A. Cross, unpublished results). qq
Here we exploit the sensitivity of the 17 O chemical shift to the local ion environment for characterizing cation solvation by the Leu10 carbonyl oxygen that helps to form the binding site for ions in the gA pore. In order to macroscopically align the gA-containing bilayers for NMR experiments and to maintain the gA pore fully hydrated and accessible to various ions, we employed lipid nanotube arrays formed inside nanoporous substrates. With the surfaces of both lipid bilayer leaflets fully accessible to aqueous solutes, we were able to utilize physically the same gA sample in a lipid bilayer environment to study reversible effects of mono- and divalent ion binding on the chemical shift properties of gA Leu 10 carbonyl oxygen. We also compare the 17 O shifts induced by ion binding to those induced by the binding of protons in the pH range from approximately 1 to 12 and find a significant difference. This unexpected result points to a difference in mechanisms for metal ion (28) and proton (31) conduction by the gA pore. Additionally, temperature and pH ranges for the nanopore alignment method are being established. The effect of lipid bilayer phase on gA Leu 10 carbonyl 17 O line width also has been investigated.
SUMMARY OF THE INVENTION
With the foregoing in mind, the present invention advantageously provides a method for detection of ligand-cell membrane protein binding by solid state NMR spectroscopy. The method starts by forming lipid bilayers inside nanopores of an anodic aluminum oxide (AAO) substrate, the lipid bilayers containing a membrane protein sample. The AAO/lipid preparation is treated with a candidate ligand having potential binding affinity for the membrane protein. Solid-state NMR analysis is performed on this treated AAO/lipid preparation so as to generate an NMR spectrum for the treated membrane protein. The solid-state NMR spectrum of the treated membrane protein is compared with the spectrum of an identical membrane protein in an untreated preparation. It is then determined whether the solid-state NMR spectrum of the treated membrane protein has shifted from the NMR spectrum of the untreated membrane protein, a shift being indicative of protein binding by the candidate ligand.
In another embodiment of the present invention, a method of screening drug candidates for binding affinity to a cell membrane protein includes supporting lipid bilayers containing the membrane protein in nanopores of a plurality of AAO/lipid preparations. This is followed by treating a portion of AAO/lipid preparations with a drug candidate or a cocktail of drug candidates. The method continues by generating a solid-state NMR spectrum of the membrane protein in the AAO/lipid preparations and generating a solid-state NMR spectrum of the membrane protein in the presence of the candidate drug or drug cocktail. Then, the method ends by comparing the solid-state NMR spectra of the membrane protein from the treated and untreated AAO/lipid preparations and equating a shift in the solid-state NMR spectrum of the treated membrane protein when compared to the untreated membrane protein as an indication of binding of the membrane protein by one of the drug candidates.
In yet another embodiment, the invention includes a solid-state NMR method for screening candidate drug binding affinity for cell membrane proteins. The method begins by introducing self-assembling lipid bilayers into nanopores of anodic aluminum oxide (AAO) support substrates, the lipid bilayer containing a cell membrane protein. The method continues by positioning the preparation in a specially designed NMR flow cell and placing the cell within the radio-frequency solenoid of the NMR instrument. A cocktail of candidate drugs is flowed through the flow cell and the AAO/lipid preparation while in the NMR instrument. A solution free of drugs is then flowed through the cell to wash the candidate drugs out of the preparation so that the cell membrane protein contained therein becomes an untreated control. A solid-state NMR spectrum is then generated for the cell membrane protein in the absence of the potential drugs. Finally, detection of a candidate drug binding to the cell membrane protein is indicated by a shift in the solid-state NMR spectrum of the cell membrane protein from the treated preparations over the untreated control preparations. The process can be repeated without removing the preparation from the NMR instrument.
BRIEF DESCRIPTION OF THE DRAWINGS
Some of the features, advantages, and benefits of the present invention having been stated, others will become apparent as the description proceeds when taken in conjunction with the accompanying drawings, presented for solely for exemplary purposes and not with intent to limit the invention thereto, and in which:
FIG. 1 depicts an embodiment of the present invention wherein a single lipid bilayer aligned inside a nanopore as a multilamellar aqueous dispersion of phospholipids is drawn inside the pores by capillary action and an arrayed structure of nanoporous channels of anodic aluminum oxide membranes is illustrated on the right;
FIG. 2 shows 31 P proton-decoupled 7 T NMR spectra of DMPC bilayers uniformly aligned by the nanoporous support at 25° C. DMPC bilayers were prepared in 10 mM Hepes buffer at pH 5.7 (A) and were exposed to 20 mM MnCl 2 for 20 min (B), followed by washing with excess 50 mM dipotassium EDTA salt for 30 min (C); the 31 P chemical shift of 85% H 3 PO 4 was referenced as 0 ppm;
FIG. 3 shows 17 O NMR spectra of 17 O-[D-Leu10]-gA uniformly aligned in DMPC bilayers in the absence and presence of KCl (2.4 M) with a peptide:lipid ratio of 1:16 and excess hydration in AAO-aligned nanotubular bilayers. Spectra were acquired in; 4 h at 40° C. using an NHMFL static probe at 19.6 T and processed with 5 ppm of line broadening; the lipid bilayer sample contained approximately 2 μmol of 17 O-[D-Leu 10 ]-gA and was aligned with the magnetic field parallel to the bilayer surface; note that the 0 ppm peak is caused by the natural abundance 17 O water signal and that the δ=196 ppm resonance is somewhat asymmetric and therefore may contain some residual contribution from the δ=178 ppm component corresponding to an unoccupied gA channel;
FIG. 4 . shows 17 O NMR spectra of 17 O-[D-Leu 10 ]-gA uniformly aligned in fully hydrated DMPC bilayers with a peptide:lipid molar ratio of 1:16 at various temperatures; each spectrum was obtained with the NHMFL static probe at 19.6 T using approximately 2 h acquisition and processed with 5 ppm line broadening; the lipid bilayer sample contained approximately 2 μmol of 17 O-[D-Leu 10 ]-gA and was aligned with the magnetic field parallel to the bilayer surface. All spectra from 37° C. to 77° C. were normalized by the amplitude of the carbonyl peak;
FIG. 5 depicts 17 O NMR spectra of 17 O-[D-Leu 10 ]-gA in DMPC bilayers uniformly aligned by AAO at various pH values and excess H 2 O with a peptide:lipid molar ratio of 1:16; other experimental conditions were as in FIG. 4 ; the resonance at 80 ppm at pH (1 is likely to be attributed to a natural abundance signal from a group that is protonated at very low pH. It should be noted here that the latter peak essentially disappeared on raising the pH; thus, it cannot be related to an irreversible process, such as lipid hydrolysis, that could occur at pH (1;
FIG. 6 demonstrates NMR signal changes upon binding drug, for example, solid-state NMR spectra of the drug target will be observed to shift, in this case spectra of the M2 Protein from Influenza A virus (a membrane protein drug target for Rimantadine and Amantadine (AMT) that are on the market today) shows dramatic changes upon Amantadine binding (red is w/AMT; blue is w/o AMT); these spectra were obtained using glass slide preparations;
FIG. 7 is a photo of a prototype NMR sample flow cell according to the present invention;
FIG. 8 shows the flow cell of FIG. 7 inserted into rectangular radio-frequency solenoid of the NMR instrument; and
FIG. 9 provides a perspective view (A) and a cross-sectional elevation view (B) of the AAO sample-flow cell of FIGS. 7 and 8 in a low-E coil assembly; the rectangular sample cell is shown in the center in B and the end plugs are adjacent the sample cell ends.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which preferred embodiments of the invention are shown. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. Although methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention, suitable methods and materials are described below. Any publications, patent applications, patents, or other references mentioned herein are incorporated by reference in their entirety. In case of conflict, the present specification, including any definitions, will control. In addition, the materials, methods and examples given are illustrative in nature only and not intended to be limiting. Accordingly, this invention may, however, be embodied in many different forms and should not be construed as limited to the illustrated embodiments set forth herein. Rather, these illustrated embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Other features and advantages of the invention will be apparent from the following detailed description, and from the claims.
Materials and Methods
Preparation of 17 O-[D-Leu 10 ]-Gramicidin A and Nanopore-Supported Lipid Bilayers.
The 17 O-[D-Leu 10 ]-gA was prepared as described previously (29), resulting in material with 57% enrichment of 17 O isotope (H 17 2 O from Cambridge Isotope Labs, Andover, Mass.). The dry peptide was codissolved with DMPC in a 1:16 molar ratio in benzene/ethanol (20:1 v/v) solvent (28) and pipetted onto the nanoporous support. The organic solution containing gA and DMPC was rapidly adsorbed. This commercial substrate, “20 nm” Anodisc 13 membranes (Whatman International), is shaped as disks 13 mm in diameter that are approximately 60 mm thick. For 31 P NMR experiments AAO disks were cut into strips less than 5 mm in width to fit into a rectangular approximately 600 μL sample coil. We have also designed a special coil for 17 O NMR that required no disk cutting. Typically, stacks of up to 40 AAO strips or disks were employed for NMR measurements. The disks have a well-aligned through-film porous structure with nanochannels directed perpendicular to the disk outer surface.
The manufacturer specifies that these nanoporous substrates have a 20-nm filtration diameter cutoff. Examination of these substrates with SEM (A. M. Alaouie, unpublished results) yielded an average pore diameter of 177±20 nm on one side, whereas the average diameter for the filtration side was 29±7 nm. Because the filtration layer is only about 2 mm thick, it is expected that only a negligible amount of lipid will be confined there. After soaking the AAO strips with gA-DMPC solution, we removed the solvent by evaporation in a hood followed by overnight vacuum drying. Substrates with deposited lipids were soaked in water and/or aqueous solutions at 45° C. for at least 4 h. Then 30-40 individual nanoporous AAO strips were stacked, and the sample holder was sealed to maintain a high level of hydration. The sample preparation protocol was also tested with pure DMPC (i.e., gA was not added).
31 P Solid-State NMR Spectroscopy
31 P Proton-decoupled NMR experiments were performed at 40° C. with a Bruker data acquisition system at 7 T equipped with an NHMFL variable-temperature 1 H/ 31 P double resonance static probe (Solid State NMR Facilities at NHMFL. All 31 P chemical shifts are presented relative to the resonance of an 85% solution of H 31 PO 4 at 0 ppm.
17 O Solid-State NMR Spectroscopy
17 O NMR experiments were performed with a Bruker data acquisition system at 19.6 T equipped with an NHMFL variable temperature single resonance static probe tuned to the 17 O operating frequency of 112.5 MHz and utilizing a large, 600-μL, rectangular sample coil (15×9×5 mm) specifically designed to fit the stacks of the Anodisc 13 substrate. The experiments employed a quadrupolar echo (29) with an 8-ms recycle delay without proton decoupling. All 17 O chemical shifts were referenced to liquid H 2 O at 0 ppm. The temperature was equilibrated for at least 15 min in all experiments. Solute exchange and pH titration experiments were carried out by exposing the Anodisc stacks for a period of at least 1 h to a manifold excess of exchangeable solute molecules at 43° C., that is, well above the main phase transition temperature of DMPC bilayers, T m ≈24° C. All 17 O measurements presented here utilized aligned samples oriented in such a way that the magnetic field was parallel to the bilayer surface.
Inherently low NMR sensitivity associated with low-g nuclei such as 15 N, 17 O, and 13 C in proteins dictates the best possible filling factor without compromising sample alignment for NMR experiments. Thus, the signal/noise ratio (S/N) of the 17 O resonance at 19.6 T from the AAO sample preparation protocol described here was compared to that on a conventional glass support (29, 30) and found to be similar, suggesting that approximately the same amount of peptide-containing lipid bilayers was deposited by both methods.
Results
Solvent Accessibility of Nanotubular Lipid Bilayers
In order to test whether both leaflets of DMPC bilayers deposited into AAO nanopores are accessible to solvent, we have monitored the 31 P resonances of lipid head groups in the absence and presence of paramagnetic Mn 21 ions. AAO-supported lipid nanotubes were prepared by deposition from multilamellar DMPC dispersion in a Hepes buffer (16, 17). This method produced fully hydrated and well-aligned nano-tubular bilayers as confirmed by 31 P NMR. Specifically, we observed a sharp resonance centered at δ ⊥ 26 −12 ppm when the substrate is aligned with the nanopores parallel to the magnetic field B 0 ( FIG. 2 A). This is consistent with the bilayers forming cylindrical tubes in the nanopores with the bilayer normal perpendicular to the axis of the nanopore and B 0 . The broad and much less intense background signal is attributed to phosphate in the AAO matrix that was prepared by an oxalic acid process.
External and inner (sealed) surfaces of lipid bilayers can be discriminated by observing differential broadening and/or shift of lipid resonances in the presence of paramagnetic ions that are likely to interact with the lipid phosphate groups situated at the bilayer surface (32). We have chosen to use paramagnetic Mn 2+ instead of commonly used lanthanide shift reagents because we were concerned with the possible chelation of the latter trivalent ions by the lipids and/or AAO surfaces. Mn 2+ ion is known to effectively increase the 31 P T 2 relaxation time that leads to excessive line broadening. Indeed, after the lipid nanotube sample was exposed at T≈43° C. to an excess of 20 mM MnCl 2 by dipping AAO chips into the solution for 20 min, the narrow lipid 31 P signal was completely broadened ( FIG. 2 B). Thus, we can conclude that the lipid head groups of both leaflets of AAO-supported bilayers were fully exposed to the ion-rich buffer and that the sample contained no sealed/inaccessible bilayers even with an average of four nested bilayers.
More importantly, for AAO-supported lipid bilayers prepared and manipulated as described here, such an exposure to metal ions can be reversed without destroying the macroscopic lipid alignment. Specifically, by dipping the AAO chips containing DMPC bilayers with bound Me into a 50 mM solution of dipotassium EDTA salt for 30 min and then immediately immersing the sample in a buffer without paramagnetic ions (all at T≈43° C.), we were able to recover; 70 6 5% of the 31 P signal ( FIG. 2 C). This demonstrates effective removal of Mn 2+ ions from bilayer surfaces. The incomplete recovery is likely caused by a partial washoff of the inner DMPC lipid nanotubes from the AAO nanopores. This was further confirmed in titration experiments with diamagnetic ions: after 15 wash cycles the 31 P signal decreased to approximately 30±5% of the initial intensity.
Reversible Ion Binding to Gramicidin a Pores
The Leu 10 carbonyl in the gramicidin A pore is one of three carbonyl sites involved in K + binding. We have monitored K + binding using the 17 O resonance of selectively labeled Lee carbonyls of gramicidin A dimers incorporated into DMPC bilayers and aligned using the AAO method. AAO substrates were positioned with the nanopore channels aligned with B 0 , and therefore both the bilayer normal and the gramicidin A pore would be approximately perpendicular to B 0 ( FIG. 3 , cartoon at top). If the tumbling of gA around the channel axis is fast, as is the case when DMPC bilayers are in a fluid phase, the gA-Leu 10 17 O NMR spectrum should be largely dictated by the average of the two principal axis components of the chemical shift tensor, δ22 and δ33. The latter values were estimated from a powder pattern spectrum observed for a lyophilized gA powder, δ22≈400 and δ33≈−35 ppm (29). For fully hydrated and rapidly tumbling gA in AAO-supported DMPC bilayers oriented in a magnetic field, as shown by a cartoon in FIG. 3 , the 17 O resonance is expected to appear at approximately δ=(δ 22 +δ 33 )/2≈183 ppm. The experimentally observed resonance at d 178 ppm ( FIG. 3 A) is close to the predicted value. Quadrupole relaxation largely determines the 15-25 ppm width of the 17 O resonance at 19.6 T.
Because the surfaces of nanotubular bilayers are fully accessible to water-soluble molecules, we were able to study the reversible binding effects of K + to the gramicidin A channel from the 17 O chemical shift using the same sample without losing its macroscopic alignment. When the gADMPC-loaded AAO stack was exposed to 2.4 M KCl to generate approximately double occupancy of K + in the dimeric channel, or one ion per monomer, a downfield shift of Δδ≈18 ppm is observed ( FIG. 3B ). Following K + removal by the EDTA wash procedure we established for Mn 2+ ions, the 17 O resonance returns to its original position ( FIG. 3 C).
17 O NMR Gramicidin A Variable Temperature Experiments
In order to study the influence of temperature on the 17 O-[DLeu 10 ]-gA resonance and stability of the AAO alignment, we have conducted a variable temperature experiment from 23 to 77° C. ( FIG. 4 ). At 23° C. the DMPC bilayer is in the gel phase, and rotational diffusion of the gramicidin A channel around its helical axis is expected to be too slow to effectively average anisotropic δ22 and δ33 components. These conditions yield a very broad line that was undetectable at the current noise level ( FIG. 4 , top). Above the phase transition temperature (T m ≈24° C.), a single resonance corresponding to fast motional conditions was detected. Importantly, the single resonance line was observed at temperatures as high as 77° C. ( FIG. 4 , bottom), indicating exceptional stability and macroscopic alignment of lipid nanotubular structures over a wide temperature range. A deterioration of signal/noise with increase in temperature is also noticeable. This can be attributed to the decrease in population difference between the spin states in equilibrium as well as to the decreased probe performance and higher thermal noise originating from the probe itself. The downfield resonance shift of up to 8 ppm at higher temperatures could be attributed to a variety of factors such as 1), changes in the chemical shift tensor components and 2), contributions of nonaxial tumbling modes. Nonaxial tumbling modes could also be responsible for broadening of the carbonyl 6.178 ppm resonance with temperature.
pH Titration of Gramicidin A Leu 10 Ion-Binding Site
Gramicidin A conducts a wide variety of monovalent cations including protons. Here, we provide an example of an NMR titration experiment in which we monitored the 17 O resonance of D-Leu 10 carbonyl in AAO-aligned gA. The titration was started at pH=7.0 by exposing the sample to an excess (about 20 mL) of 10 mM phosphate buffer with successive pH changes to 5.2, 2.8, <1 (1.4 M H 3 PO 4 ), 8.4, and 0.12 (0.1 M NaOH), all at T about 43° C. The entire titration experiment was carried out with the same DMPC-gA sample by immersing the stack of AAO substrate chips into a desired buffer for 20 min. Remarkably, from pH (1.0 to pH=8.4, i.e., over 7 orders of magnitude in proton concentration, no changes in the 17 O peak position were observed ( FIG. 5 ). At pH <1.0 (1.4 M H 3 PO 4 ), the proton concentration was comparable to that of K + in FIG. 3 , in which the downfield shift of 18 ppm was observed. Thus, we must conclude that proton conductance by the gA channel is not accompanied by structural changes or significant changes in the electrostatic environment measurable by 17 O NMR, although the conductance of small monovalent ions such as K + does affect these parameters. A small downfield shift of the 17 O line was observed at pH 12 ( FIG. 5 , bottom). At such an alkaline pH, one could expect initial formation of aluminum hydroxide in the pores. Overall, FIG. 5 demonstrates excellent stability of AAO-aligned lipid bilayers incorporating gramicidin A channels over a wide range of pH.
Discussion
31 P NMR data presented here demonstrate full accessibility of both leaflets of nanopore-confined lipid bilayers to paramagnetic Me ions. Moreover, we have shown that the broadening of the 31 P resonances is reversible by a gentle treatment of the AAO stack with the chelating agent EDTA (ethylenediaminetetraacetic acid) followed by a straightforward buffer exchange at temperatures above the main phase transition. These conditions were chosen to facilitate ion exchange because of a well-documented decrease in both lipid packing and local order parameter for lipids in the fluid phase.
Earlier 31 P NMR data on accessibility of polar headgroups of POPC (1-palmitoyl-2-oleoyl-sn-glycero-3 phosphocholine) bilayers absorbed into AAO nanopores to Pr 3+ shift reagent have shown that when the bilayer is maintained in the fluid bilayer phase, the ends of some of the lipid tubules appeared to be sealed against the pore such that the ions could not access all of the phosphate groups (21). However, when the sample was lowered below the main phase transition temperature, this seal was broken, as indicated by a shift in the 31 P resonances for all phosphates. In our buffer exchange NMR experiments the sample was always maintained at T=40-43° C., although we cannot exclude that the sample temperature was lowered below that of the DMPC main phase transition (T m about 24° C.) for a short time when the sample was transferred from the NMR spectrometer to a new buffer. We are investigating this issue further.
Regardless of the actual AAO-supported DMPC bilayer macrostructure and mechanism of solvent accessibility, we conclude that our experimental conditions result in fully accessible nanopore-confined lipid bilayers to water-soluble ions and/or chelating complexes such as EDTA. Importantly, we also observed that during these multiple solvent manipulations the macroscopic lipid alignment was maintained as assessed by 31 P NMR. Additional 31 P NMR experiments indicated that the alignment was maintained after the sample was exposed to −80° C. for a few hours and then brought back to 40° C. (not shown). This is in support of the initial work on AAO-supported lipid bilayers that showed macroscopic lipid alignment in these nanotubular structures at temperatures as low as −123° C. (16). Such exceptional stability of AAO-supported lipid bilayers to temperature variation and low-temperature storage conditions might be very advantageous over the conventional glass-plate method. Typically, the latter samples cannot be frozen or put through a freeze-thaw cycle without losing lipid alignment.
High-field 17 O NMR spectroscopy of gA in hydrated DMPC bilayers that were uniformly aligned by the AAO-nanopore method yielded a single d p 178 ppm resonance for the 17 O-DLeu 10 carbonyl site when the sample was maintained above T P 24° C. The observation demonstrates that when the DMPC nanotubular bilayer is in a fluid phase, the tumbling of the gA helix around the pore axis is fast enough to effectively average the δ22 and δ33 chemical shift tensor components. With further increase in temperature, the width of the carbonyl δ≈178 ppm resonance increases slightly (most noticeable from 67° C. to 77° C.). We attribute this broadening to a contribution of nonaxial tumbling modes rather than to a decrease in the axial peptide tumbling. An increase in nonaxial tumbling is also consistent with the downfield resonance shift of up to 8 ppm at 77° C. Overall, confinement of lipid bilayers to the nanopores does not appear to have effects on the peptide tumbling, at least to an extent that would be noticeable from 17 O NMR line shapes.
In our experiments this dimeric ion channel was fully accessible to the aqueous solvent, allowing a series of cation exchange and titration experiments to be carried out with physically the same sample. Specifically, we observed that reversible binding of K + resulted in a Δδ≈18 ppm down-field shift of the 17 O resonance at δ ⊥ that is about half of the 40 ppm shift at δ∥ reported for DMPC-gA samples aligned by glass slides (29). This difference in Dd arises from the orientation of the gA channel with respect to the magnetic field, B0: for glass-aligned samples the ion channel was parallel to B 0 , and the 17 O resonance was dictated by δ∥=δ 11 , whereas for the AAO-aligned sample, the channel was perpendicular to B 0 , so the resonance was centered at δ ⊥ ≈δ 22 +δ 33 ). The later two tensorial components are less sensitive to ion binding than δ 11 (33). The changes in δ∥ and δ ⊥ could be induced by polarizabilty effects when K + is solvated by the Leu 10 carbonyl. Solvation of K + by the channel is known to affect the individual principal components of the 15 N chemical shift tensor of Trp 11 in the same peptide plane with the Leu 10 carbonyl oxygen (28). Additionally, a structural change by just a few degrees of tilt of the peptide plane toward the ion can cause a decrease of δ∥ and an increase in δ ⊥ (34). It is also possible that the 17 O resonance we observed at 2.4 M KCl contains a fraction of the residual unshifted resonance corresponding to unbound K + . More studies are needed to evaluate these effects.
Exposing the gA channel to a high proton concentration did not result in any measurable shift of the 17 O-D-Leu 10 carbonyl resonance. This unexpected result points to a difference in mechanisms for monovalent metal ion and proton conduction by the gA pore.
The experiments described here are made possible by the use of nanoporous AAO-supported bilayers. Typically, macroscopically aligned glass-supported lipid bilayers cannot be immersed in a buffer without losing much of the lipid in the form of vesicles. Whereas AAO nanopores host only a few individual lipid bilayers, the glass plates sandwich a few thousand bilayers, a three order of magnitude difference. As a result, the AAO-supported bilayer sample is more stable, as demonstrated by the variable temperature experiments up to 77° C. To maintain stability, the hydration level of the glass-supported samples is lower than that of the MO-alignment method where maximal hydration is coupled with good macroscopic alignment and insignificant lipid loss on changing the solvent environment. The aligned nanoporous AAO substrate provides the advantages of fast accessibility by solute molecules, reversible ion exchange, and titration experiments with physically the same sample of membrane protein. Thus, one can achieve significantly better control of the bilayers by exposing the lipid nanotubes to various solutions and fine-tuning the bilayer properties by exchanging solvents with the bulk solution. In contrast, the aqueous phase of the lipid bilayers that are sandwiched between glass plates cannot be manipulated with the same ease. Typically, only gaseous exchange experiments can be carried out (35), and those are typically slower and significantly more difficult to control, especially for hygroscopic lipids.
The use of AAO-supported bilayers offers distinct advantages over both glass-slide-supported bilayers and magnetically aligned bicelle samples. The fraction of the sample volume occupied by the hydrated lipid-protein sample is approximately the same in all three classes of aligned samples. The significant fraction of MO or glass is offset by the high aqueous fraction in the bicelle samples. The AAO- and glass-supported samples have the advantage over bicelles where there is considerable isotropic averaging leading to an order parameter of approximately 0.8. The AAO and bicelle samples have the advantage that sample conditions can be easily changed without remaking the entire sample. AAO substrate-aligned samples are also advantageous in experiments with hydrated bilayer samples because of their intrinsic ability to suppress thermal gradients arising in NMR experiments at high RF power and frequencies (36). Indeed, the thermal conductivity of alumina is about 25-35 W m −1 K−1 (37) versus only about 0.6 W m −1 K −1 for water (38). It also compares very favorably with thermal conductivity of glass of about 1.1 W m −1 K −1 (37).
Although lipid formulations for bicelles that align in external magnetic field under acidic and basic pH values and extended temperature ranges have been reported in the literature (9, 10), the choices of lipid composition for such systems remain limited. Experiments carried out at the authors' NCSU laboratory indicate that macroscopically aligned lipid nanotubular bilayers can be assembled from various lipids including anionic and also lipid-cholesterol mixtures (Alaouie, A. M. and A. I. Smirnov, unpublished data). Moreover, differential scanning calorimetry data have shown that the bilayer thermodynamics is perturbed to a much smaller degree than for lipid bilayers formed on planar substrates (19, 20). Specifically, the main phase transition temperature for AAO-supported DMPC was found to be the same as for unsupported multilamellar bilayers (20). Thus, it appears that the lipid bilayers in nanoporous AAO can be maintained in the same thermodynamic phase at the same temperature as the unsupported bilayers. From this perspective, AAO-supported bilayers should provide a better mimic for native bilayers in terms of thermodynamic properties and hydrophobic matching as compared with bicelles that have altered phase behavior.
One limitation of the AAO nanopore method is that only a single unique orientation of the bilayer normal with respect to B 0 can be achieved by aligning the nanopores along B 0 . The perpendicular orientation would result in broad NMR line shapes determined by a cylindrical powder pattern. “Unflipped” bicelles also align with the bilayer normal perpendicular to the external magnetic field, the same bilayer orientation we employed for AAO-supported samples. Although bicelles can be flipped by adding lanthanides directly to lipid-protein systems (7) or to a chelating phospholipid (39), further studies are needed to find whether such manipulation of the bilayer-water interface would affect bilayer properties and/or protein rotational diffusion.
Summary
We conclude by remarking on the convenience of utilizing nanoporous AAO substrates for aligning lipid bilayers containing membrane proteins for solid-state NMR studies. In our experience, the AAO strips can be handled easily because the bilayer surfaces are well protected by the rigid structure of the substrate. The stack can be disassembled and reassembled as needed and stored in a −80° C. freezer for a long time without losing lipid and membrane peptide alignment. These properties are maintained in a very broad pH range (1-12) and temperatures as high as 70° C. We also demonstrate that the surfaces of both leaflets of such bilayers are fully accessible to aqueous solutes. Thus, high hydration levels as well as pH and desirable ion and/or drug concentrations could be easily maintained and modified as desired in a series of experiments with the same preparation of membrane protein sample. We are proposing that a large number of solid-state NMR-based studies will benefit significantly from the method described here. It will be possible to carry out a wide range of titration experiments with higher precision, shorter time, and less protein because the sample can be reused effectively without redepositing it onto the substrate. The latter feature is especially important for isotopically labeled membrane proteins that are difficult and/or expensive to express in large quantities. Another type of NMR experiment that will benefit significantly from faster solution delivery is 2 H exchange: fully accessible AAO nanochannels will provide better temporal resolution than samples aligned on glass plates (40, 41). Designing flow-through systems and integrating those with existing NMR probes would automate solvent-exchange experiments and further improve temporal resolution. Structure-function and drug-screening solid-state NMR studies could then be carried out by incorporating the protein of interest into AAO-supported lipid nanotubes and exposing the sample to various drugs and other solute molecules. In such studies a sequence of solutions could be utilized to study competitive binding or sequential conformations of membrane proteins.
In the drawings and specification, there have been disclosed typical preferred embodiments of the invention, and although specific terms may have been used, the terms are used in a descriptive sense only and not for purposes of limitation. The invention has been described in considerable detail with specific reference to these illustrated embodiments. It will be apparent, however, that various modifications and changes can be made within the spirit and scope of the invention as described in the foregoing specification and as defined in the appended claims.
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41. Tian, C. L., P. F. Gao, L. H. Pinto, R. A. Lamb, and T. A. Cross. 2003. Initial structural and dynamic characterization of the M2 protein transmembrane and amphipathic helices in lipid bilayers. Protein Sci. 12:2597-2605. | Disclosed is a method for detection of ligand-cell membrane protein binding by solid state NMR spectroscopy. The method starts by forming a lipid bilayer inside nanopores of an anodic aluminum oxide (AAO) substrate, the lipid bilayer containing a membrane protein sample. The AAO substrate is treated with multiple candidate ligands having potential binding affinity for the membrane protein. Solid-state NMR analysis is performed on the treated AAO/lipid preparation so as to generate an NMR spectrum for the treated membrane protein. The solid-state NMR spectrum of the treated membrane protein is compared with the spectrum of the same preparation of membrane protein in the absence of the ligands. It is then determined whether the solid-state NMR spectrum of the treated membrane protein has shifted from the NMR spectrum of the untreated membrane protein, a shift being indicative of protein binding by the candidate ligand. | 6 |
BACKGROUND OF THE INVENTION
The present invention relates to a control system for applying and releasing a vacuum from a work-gripping vacuum cup employed as the work-gripping element of a workpiece transporting or locating device. Such devices are widely employed in mass-production environments, typically to load and unload sheet metal parts into and from a die or to carry a part, such as an automobile windshield, to the vehicle to which it is to be installed.
Typical examples of prior art vacuum cup control systems of the type with which the present invention is concerned are found in U.S. Pat. Nos. 3,349,927; 3,568,959; 3,613,904; 3,712,415; and 4,453,755.
The foregoing patents employ a venturi passage which is connected to a source of air under pressure. Flow of air through the venturi passage induces a subatmospheric pressure in the throat of the venturi, and a passage connecting the venturi throat to the interior of the vacuum cup will induce a vacuum within the cup when the cup is applied to a workpiece surface. In the earlier of the patents identified above, it was necesary to maintain the flow of air through the venturi passage in order to maintain the vacuum in the cup because the air withdrawn from the cup flowed into the venturi passage and to the discharge vent at the end of this passage. Upon cessation of the air flow, air at atmospheric pressure was free to flow in the reverse direction through the discharge vent, venturi passage and into the vacuum cup to dissipate the vacuum. Efforts to address this problem involved the addition of structure which substantially increased the profile of the control device. This was a definite disadvantage in those applications where the cup is employed to load and unload a part from a die because the enlarged profile requires a larger die opening to provide clearance for movement of the part-handling device into and out of the die.
A second problem encountered with the earlier devices was that of quickly releasing the vacuum from the cup to release the workpiece at the conclusion of the handling operation. The passage from the discharge vent to the vacuum cup is a relatively restricted passage, and the rate of flow through this passage would diminish substantially as the pressure differential between the negative pressure within the cup and atmospheric pressure approached equalization.
In U.S. Pat. No. 4,453,755, an arrangement for conducting air from the air pressure source to the interior of the vacuum cup to achieve rapid release is disclosed; however, this approach again substantially increases the profile of the control device by the addition of a rather complex valving arrangement to the exterior of the venturi passage housing.
The present invention is directed to a control device for a vacuum cup which is of extremely compact exterior dimensions and which will automatically maintain an induced vacuum in the cup upon cessation of air flow through the venturi passage and which will achieve a rapid release of the vacuum when desired.
SUMMARY OF THE INVENTION
In accordance with the present invention, a control system for controlling the application and release of a vacuum to a workpiece-gripping vacuum cup includes a housing of relatively compact dimensions through which a venturi passage of conventional configuration extends from a venturi passage inlet to a discharge vent which is preferably fitted with a silencer. A branch passage extends through the housing from the venturi throat to a control port located to open into the interior of a vacuum cup mounted on the housing. The venturi passage inlet is connected to a source of air under pressure via a supply conduit fitted with a normally closed on-off valve which is arranged to be opened for timed intervals. When the valve is opened, air under pressure is discharged from the source through the conduit and through the venturi passage, withdrawing air in a well-known manner from the vacuum cup interior via the branch passage. A one-way check valve in the branch passage accommodates flow through the branch passage in the direction from the control port to the venturi throat but automatically closes to prevent flow through the branch passage in the reverse direction. Flow of air through the venturi passage is for a timed interval sufficient to apply the desired degree of vacuum in the vacuum cup. Upon cessation of the air flow through the venturi passage, the vacuum is held in the cup by closure of the one-way check valve in the branch passage.
To release the vacuum cup from the workpiece, a second passage extends through the housing from a second inlet to the control port. This second inlet is connected by a second conduit and a second on-off valve to the source of air under pressure. This last on-off valve is normally closed and the second passage within the housing is provided with a spring-loaded, one-way ball check valve which seats toward the second inlet. The spring loading of this valve is sufficient to maintain the ball seated in the face of vacuum in the cup but is insufficient to maintain the ball seated when pressure from the source is applied to the second inlet to the housing. When the second inlet is connected to the pressure source, by opening of the valve in the second conduit, air under pressure flows past the ball check valve and through the control port into the vacuum cup to rapidly release the vacuum.
Other objects and features of the invention will become apparent by reference to the following specification and to the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevational view of a control system embodying the present invention with the air supply system omitted and certain parts broken away or shown in section;
FIG. 2 is a top plan view of the structure shown in FIG. 1, including a schematic diagram of the air supply system, with certain parts broken away or shown in a partial section taken approximately on the line 2--2 of FIG. 1;
FIG. 3 is a cross-sectional view of the housing shown in FIG. 1, taken approximately on the line 3--3 of FIG. 1; and
FIG. 4 is a perspective view of a check valve shown in section in FIG. 3.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring first particularly to FIGS. 1 and 2, a vacuum cup designated generally 10 is provided with a fitting 12 at its upper end which is received with a T-slot 14 formed in the bottom of a housing designated generally 16. A generally hemispherical projection 18 formed on housing 16 is received within a recess 20 (FIG. 2) in a bracket arm 22 and clamped within the recess as by a clamping bolt 24. Bracket arm 22 is in turn adjustably clamped upon a rod-like frame member 26 which constitutes part of a movable frame (not shown) employed to mount and move vacuum cup 10 as may be required to move a workpiece W (FIG. 1) from one position to another. Typically, the workpiece will be a sheet metal panel which will be gripped by a group of vacuum cups during the transfer operation. Such transfer devices are well known and do not per se relate directly to the present invention which is specifically concerned with a control system which operates to apply or release a vacuum from the interior of vacuum cup 10.
The interior 28 of vacuum cup 10 communicates at the top of the cup with a vertical passage 30 which extends upwardly through the mounting fixture 12 to open at the top of the fixture. When vacuum cup 10 is mounted within T-slot 14 in housing 16, the upper end of bore 30 communicates directly with the lower end of a control port 32 (FIG. 3) opening through the bottom of housing 16 into T-slot 14.
Referring now particularly to FIG. 2, a venturi passage 34 extends through housing 16 from an inlet 36 at one end of the housing to a discharge opening 38 at the opposite end of the housing. A silencer 40 may be mounted at the discharge end of the housing.
Venturi passage 34 is of a conventional, well-known configuration and a nozzle 42 is mounted within the passage. As is well known, flow of air through passage 34 from left to right will induce a subatmospheric pressure in the region of the throat or small diameter section of the venturi. This region of reduced pressure is employed to induce a vacuum within the interior of vacuum cup 10 by the provision of a passage 44 (FIG. 3) which extends from the region of reduced pressure in the venturi passage 34 to control port 32 which, as explained above, opens into the interior of vacuum cup 10.
A one-way check valve designated generally 46 is mounted within passage 44 and oriented to permit flow from control port 32 to venturi passage 34 when the pressure at control port 32 exceeds the pressure in passage 34. When air is flowing through venturi passage 34, a subatmospheric pressure will be induced in the upper end of passage 44 and air will flow from the interior of vacuum cup 10 upwardly into control port 32, through valve 46 and upwardly into venturi passage 34 until the pressure within the interior of vacuum cup 10 is equalized with that existing in the subatmospheric pressure region of venturi passage 34.
Check valve 46 is of a one-piece molded construction of rubber or a resilient synthetic material formed into a configuration best shown in FIG. 4. The exterior of valve 46 is formed with a disk-like mounting or locating flange 48 from which upwardly protrudes a wedge-shaped outlet section 50. A cylindrical inlet portion 52 projects downwardly from the underside of flange 48.
As best seen in the cross-sectional view of FIG. 3, a passage 54 extends upwardly through the inlet 52 and wedge 50 portions of valve 46 and a slit 56 through the upper edge of wedge portion 50 defines an outlet at the upper end of passage 54. This slit 56 is normally closed. When the pressure within passage 54 of valve 46 exceeds the pressure acting on the exterior of wedge portion 50, the walls of wedge portion 50 will flex outwardly to open slit 56 to permit air to flow upwardly from passage 54 through the opened slits. If, however, the pressure acting on the exterior of wedge portion 50 exceeds that within the interior of the wedge portion, then the slit 54 will be closed to prevent flow of air through the slit. As mounted in housing 16, valve 46 thus acts as a one-way check valve which will permit air to flow from control port 32 to venturi passage 34. to evacuate vacuum cup 10 but will block the flow of air from passage 34 to control port 32 whenever the pressure at control port 32 is less than that in venturi passage 34 Once a vacuum is established within vacuum cup 10, valve 46 will lock this vacuum in place, even if the flow of air through venturi passage 34 is stopped and pressure within passage 34 returns to atmospheric pressure.
Referring now to FIG. 2, to establish an air flow through venturi passage 34, a supply conduit 58 is sealingly connected to inlet 36 and extends from inlet 36 to one control port of a solenoid-actuated, four-way reversing valve 60. A pressure source 62 is connected to an inlet port of valve 60. Valve 60 is normally centered as shown as by centering springs. Upon energization of solenoid 64, the valve shifts to the right to establish a direct connection between source 62 and conduit 58 and air flows from source 62 through conduit 58 into venturi passage 34. If at this time vacuum cup 10 is seated upon a workpiece W (FIG. 1), the flow of air through venturi passage 34 will induce a vacuum within cup 10 causing the cup to firmly grip workpiece W.
Preferably, valve 60 is actuated by a timer control T to open for a period of time sufficient to enable the resultant air flow through venturi passage 34 to induce a sufficient vacuum within vacuum cup 10 to achieve the desired grip upon workpiece W. As explained above, once this vacuum is induced, the operation of check valve 46 will maintain the vacuum within cup 10 upon the subsequent closing of valve 60 at the end of the timed interval with the resultant cessation of air flow through venturi passage 34.
In order to release the vacuum within vacuum cup 10, a second passage 66 extends into housing 16 from an inlet 68. A one-way, spring-loaded ball check valve designated generally 70 is located within passage 66 and oriented to seat toward inlet 68; that is, valve 70 will accommodate flow from inlet 68 into passage 66 but will block flow from passage 66 into inlet 68.
Referring now to FIG. 3, it is seen that passage 66 communicates with control port 32 via an inclined passage 72 through housing 16.
When a vacuum exists within cup 10, and thence at control port 32, the consequent reduced pressure in passage 66 is insufficient to overcome the biasing of the spring of the one-way check valve 70; and thus this valve will remain closed so that vacuum does not leak from cup 10.
When it is desired to release the vacuum from vacuum cup 10, solenoid 76 of valve 60 is actuated to connect pressure source 62 to conduit 74. The pressure supplied by source 62 is more than adequate to open check valve 70, and air under pressure from source 62 flows past the check valve and via conduit 72 (FIG. 3) into the control port 32 to quickly raise the pressure within the interior of vacuum cup 10 to atmospheric pressure, thus releasing the grip of vacuum cup 10 on the workpiece.
Valve 76 may be operated, if desired, with a timer control in the same fashion as valve 60; however, in most applications a manually initiated momentary opening of valve 76 is sufficient to release or dissipate the vacuum in the interior of cup 10.
While one embodiment of the invention has been described in detail, it will be apparent to those skilled in the art the disclosed embodiment may be modified. Therefore, the foregoing description is to be considered exemplary, rather than limiting, and the true scope of the invention is that defined in the following claims. | A control system for applying and releasing vacuum in a work-gripping vacuum cup includes a housing having a venturi passage for inducing a vacuum within the cup upon the flow of air through the venturi passage. A one-way check valve in a passage extending through the housing between the venturi and the vacuum cap will seal the vacuum in the cup upon cessation of flow through the venturi passage, thus enabling the cup to grip the workpiece in response to a timed pulse of air through the venturi and to maintain the grip after the air flow is stopped. A second valve controlled passage through the housing enables air under pressure to be injected into the vacuum cup to quickly release its grip on the workpiece. | 1 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] The present invention claims priority to U.S. Provisional Patent Application Serial No. 60/448,506 filed on Feb. 19, 2003 and entitled “Wall Panel For A Portable Restroom.”
TECHNICAL FIELD
[0002] This invention generally relates to a portable restroom. More specifically, to a wall panel for a portable restroom and a method of making such a wall panel for a portable restroom.
BACKGROUND
[0003] Portable restrooms are in wide-spread use today at construction sites, campgrounds, outdoor entertainment events and the like. Such portable restrooms typically have a roof connected to three side panels and a front panel having a door. The side panels and door panel are connected to a base. Prior art restrooms have wall panels that have exterior surfaces having styling lines and other features for improving the aesthetic appearance and structural integrity of the wall panel. While prior art portable restrooms incorporate wall panels that achieve their intended purpose, many problems still exist. For example, the styling lines and other features incorporated into the exterior surface of the wall panels create an interior surface of the wall panel that is replete with indentations and other features which creates a non-smooth interior surface on each of the wall panels. This non-smooth surface makes it more difficult to clean the interior surfaces of the restroom.
[0004] Therefore, what is needed is a new system and method for manufacturing the wall panels of a portable restroom. The new and improved system and method should allow the portable restroom interior to be cleaned more easily.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] Further features and advantages of the invention will become apparent from the following discussion and the accompanying drawings in which:
[0006] [0006]FIG. 1 is perspective view of the portable restroom incorporating the wall and door panels of an embodiment of the present invention;
[0007] [0007]FIG. 2 is a front view of the outside surface of the wall panel of the portable restroom of FIG. 1, in accordance with an embodiment of the present invention;
[0008] [0008]FIG. 3 is a cross-sectional view of the wall panel of FIG. 2 along lines A-A;
[0009] [0009]FIG. 4 is a front view of the inside surface of the wall panel of the portable restroom of FIG. 1; and
[0010] [0010]FIG. 5 is a flow chart illustrating a method for manufacturing a wall panel, in accordance with an embodiment of the present invention.
BRIEF SUMMARY OF THE INVENTION
[0011] In an aspect of the present invention, a portable restroom having a wall panel is disclosed. The wall panel of the present invention has an outside surface and an inside surface. The inside surface of the wall panel is smooth with out any indentations or recesses. The exterior surface of the wall panel, generally, has impressions formed therein.
[0012] In yet another aspect of the present invention, a method of making a wall panel having a smooth interior surface is disclosed.
DESCRIPTION
[0013] The following description of the preferred embodiment is merely exemplary in nature and is in no way intended to limit the invention or its application or uses.
[0014] Referring in particular to FIGS. 1 and 2, a portable restroom for use in public is generally shown and represented by reference numeral 10 . As shown in FIG. 1, the portable restroom 10 has wall panels 12 , 14 and 15 that form the sides and back of the restroom. The portable restroom 10 also includes a door panel 17 having a door as shown in phantom. It should be understood that wall panels 12 , 14 and 15 shown in phantom are substantially identical.
[0015] Portable restroom 10 also includes a roof 16 and a base 18 . As shown in FIG. 1, roof 16 and base 18 are positioned on top and bottom respectively, of wall panels 12 , 14 , and 15 . The wall panels 12 , 14 and 15 , roof 16 and base 18 form an enclosure 20 . Enclosure 20 includes a tank 22 having an aperture covered by a toilet seat 24 and a vent pipe 26 for venting gases accumulating in tank 22 out to atmosphere. The enclosure 20 also includes a toilet paper holder 28 attached to side panel 12 .
[0016] Referring in particular to FIGS. 2, 3 and 4 , wall panels 12 , 14 and 15 include an exterior surface 30 (shown in FIGS. 2 and 3) and an interior surface 32 (shown in FIGS. 3 and 4). As shown in FIG. 2, exterior surface 30 of wall panels 12 , 14 and 15 have knits or reinforcement ribs 34 to strengthen the panels (as shown in FIG. 3). The knit 34 are formed in pre-determined positions along the panel 12 such that exterior surface 30 is in contact with the interior surface 32 . Additionally, exterior surface 30 also includes style lines 36 that vary in length, and depth. These style lines 36 are indentations or raised sections on exterior surface 30 of the wall panels 12 .
[0017] In order to facilitate the cleaning of interior surface 32 of side panels 12 , 14 , and 15 interior surface 30 is smooth and does not have any reinforcement ribs or indentations or the like.
[0018] In an embodiment of the present invention, a method 50 of forming wall panels 12 , 14 , and 15 wherein exterior surface 30 is provided with knits 34 and style lines 36 and interior surface 32 is smooth is illustrated in FIG. 5. In order to form exterior surface 30 of wall panels 12 , 14 , and 15 heat is applied to a first polymer sheet such as a plastic sheet, as represented by block 52 . The first polymer sheet is further heated to a first predefined temperature, as represented by block 54 . After the first polymer sheet has been heated to the first predefined temperature, a first mold having suitable inserts to form the reinforcement ribs and styling lines are pressed into contact with the first surface of the first sheet, as represented by block 56 . At block 58 , a vacuum is applied to the mold and first sheet, which draws the first sheet into the mold and transfers the impression in the mold to the surface of the first sheet.
[0019] The interior surface 32 of wall panels 12 , 14 and 15 are formed by heating a second polymer sheet, as represented by block 60 . The second polymer sheet is heated to a second predefined temperature, as represented by block 62 . The second sheet is pressed into contact with a second mold, as represented by step 64 . The second mold has no inserts. The second sheet is formed to the desired shape by applying vacuum to the mold and second polymer sheet, as represented by step 66 . In order to form wall panels 12 , 14 and 15 , the first and the second molds are pushed together such that the first sheet having a first shape is knitted or joined to the second sheet with the second shape at pre-determined locations, as represented by block 68 . Thus, the wall panels 12 , 14 and 15 are formed of two sheets of plastic that are knitted together at predefined locations.
[0020] The above method 50 allows the side panels 12 or back panels to be formed, wherein the exterior surface has reinforcing ribs and styling lines and the interior surface is smooth. Additionally, in an embodiment of the present invention, the knits and reinforcing ribs are only formed and visible on the outside surface of the side or back wall panels of the restroom.
[0021] As any person skilled in the art will recognize from the previous description and from the figures and claims, modifications and changes can be made to the preferred embodiment of the invention without departing from the scope of the invention as defined in the following claims. | The present invention is generally directed towards a portable restroom and more specifically towards a wall panel for a portable restroom. The wall panel of the restroom has an exterior surface and an interior surface that are formed by thermoforming two plastic sheets. The exterior surface of the wall panel is formed having knit and decorative styling lines. The interior surface is smooth and free of any indentations or impressions. | 4 |
REFERENCE TO OTHER APPLICATIONS
This application is a continuation-in-part of my co-pending PCT application US01/49981, entitled “ELECTRICAL POWER GENERATION”and filed Nov. 7, 2001 designating the United States, and claims priority under 35 U.S.C. §119(e) from U.S. provisional application 60/266,841, filed Feb. 6, 2001, and, through the above-referenced PCT application, from U.S. provisional application 60/246,554, filed Nov. 7, 2000.
TECHNICAL FIELD
This invention relates to marine engine cooling and to electrical power generation, and more particularly to fuel-powered, on-board marine generators.
BACKGROUND
There are many commercially available generators, some of which are designed especially for use on board boats. A typical marine engine-generator set has a seawater-cooled engine with its crankshaft coupled to the rotor of an electrical generator, with the crankshaft and rotor collinear and horizontal as mounted in operation. Injecting the cooling seawater directly into the exhaust stream cools the engine exhaust.
On many smaller craft, electrical power generation is desirable, but space is limited. It can be particularly difficult below deck, for example, to accommodate the height of commercially available power generators. Market economics generally limit marine power generator manufacturers to the use of engines and generator components otherwise available for other, higher volume applications. A new approach to producing electrical power is needed to satisfy the market need for compact, reliable power generation.
New approaches are also desirable for cooling engines and other power-producing marine equipment. Outboard engines are known to be cooled by pumping seawater through the engine and injecting it into the exhaust stream. Because of the corrosive nature of seawater, it is recommended that such engines be regularly flushed with fresh water.
SUMMARY
I have realized that a new configuration of engine and generator components can produce an electrical power generation system suitable to meet the needs of owners of smaller watercraft, and those requiring lower output ratings. I have also realized that marine power generation equipment, such as motors, generators and the like, may be usefully cooled by circulating seawater through a heat exchanger that draws heat from a less corrosive and/or more efficient coolant flowing through the power generation equipment itself.
In one aspect of my invention, an on-board marine electrical power generator contains a conventional four-stroke, water-cooled outboard motor engine coupled to an alternator upon a transportable frame suitable for mounting on-board a boat (e.g., on a horizontal surface below deck).
By “outboard motor engine” I mean an engine designed for use in outboard motors, with a vertically-oriented crankshaft.
In some embodiments, the outboard motor engine is modified to enable its reliable operation with its crankshaft extending horizontally. In some other embodiments, the outboard engine motor shaft extends vertically and is directly coupled to an alternator rotor.
Another aspect of my invention features a fuel-powered engine with a vertically oriented shaft coupled to a vertically oriented rotor of an electrical generator laterally spaced from the engine shaft, such that the engine and generator are disposed in side-by-side relation. This configuration enables the use of commercially available, water-cooled engines and engine components from vertically-shafted, outboard marine motors, for example, while keeping the height of the overall package within a range suitable for installation on pleasure boats.
The engine preferably operates on a four-stroke, gasoline (Otto) cycle, and has an exhaust elbow adapted to mix a flow of water into the streaming exhaust to cool the exhaust before it is discharged. Four-stroke engines are particularly preferred for their ability to operate under elevated exhaust back pressures, such as are required to push water-injected exhaust streams through backwash-inhibiting exhaust risers.
The engine and generator are preferably mounted to a portable frame that may also support power-conditioning circuits for the alternator. The output shaft of the engine may be coupled to the rotor shaft of the generator by belted pulleys, for quiet power transmission at a desired speed ratio.
The alternator or generator may be of several types known in the art, but for some applications a variable speed, permanent magnet alternator is preferred. Such alternators are commonly used in generating electrical power from wind-driven turbines, for example, and can be equipped with power conditioning circuitry to provide a stable output frequency over a wide range of input speeds. An advantage of variable speed operation is that the engine can be configured to change speeds in response to load, to maintain an optimum operating efficiency and to enable the use of advantageously small, less powerful engines.
By “rotor” I mean the rotating portion of the alternator, whether carrying electrical windings as an armature, or carrying magnets.
In some embodiments, the permanent magnet alternator is coupled to the engine to run at a relatively constant, “synchronous” speed (e.g., 1800 RPM), to produce a desired output frequency. Such a configuration is appropriate for applications that will accommodate some variation in output voltage over a range of operational loads and temperatures. One advantage of this configuration is that it employs a much simpler alternator architecture than that of a wound generator stator with exciter circuits, for example, without the added expense of solid state frequency generation circuitry.
According to one aspect of the invention, an on-board marine electrical power generator includes a four-stroke, water-cooled engine with a vertically-oriented drive shaft; an alternator with a vertically oriented rotor coupled for rotation with the engine drive shaft to produce electricity and laterally spaced from the engine shaft; and a transportable frame upon which the engine and alternator are mounted in side-by-side relation.
In some applications, the generator is mounted inside a boat hull, with an exhaust system of the engine including an exhaust riser extending to above a water line of the hull. In some cases, the exhaust system extends through a transom bulkhead exhaust port, for example.
Preferably, the platform defines mounting points for securing the generator to below-deck structure.
In some embodiments, the generator also includes an enclosure surrounding the engine and alternator. In some cases, the enclosure is equipped with output power receptacles. Preferably, the enclosure admits air only for combustion, and otherwise completely encloses the engine and alternator, to significantly reduce air-borne noise from the engine and alternator.
For particular advantage in below-deck applications, for example, the generator preferably has an overall height of less than about 15 inches, more preferably less than about 12 inches. This advantageously low height is enabled with a vertically shafted engine by the side-by-side arrangement of engine and alternator.
Preferably, the generator occupies a footprint (i.e., its overall extent in a horizontal sense) with a length of less than about 25 inches and a width of less than about 15 inches. More preferably, the length is less than about 20 inches and the width is less than about 12 inches.
The engine preferably has an exhaust elbow adapted to mix a flow of water into streaming exhaust to cool the exhaust before it is discharged and, in some applications, the shaft of the engine is coupled to the rotor of the alternator by belted pulleys.
For some applications, the alternator is a variable speed, permanent magnet alternator, and the engine is configured to change speeds in response to load. For some other applications, the alternator is coupled to the engine to run at a synchronous speed.
In some embodiments, the drive shaft also turns a seawater pump, which may be directly coupled to the drive shaft at an opposite end of the engine than a pulley driving the alternator.
The engine may be cooled by a circulated coolant cooled in a liquid-liquid heat exchanger through which seawater is circulated before being injected into an exhaust system of the engine.
In some configurations the alternator is air-cooled, with air in the enclosure cooled by circulation through an air-seawater intercooler, for example.
According to another aspect of the invention, a marine electrical power generator is mounted inside a boat hull, and includes a four-stroke, water-cooled engine with a vertically-oriented drive shaft and an exhaust system including an exhaust riser extending to above a water line of the hull. A permanent magnet alternator with a cup-shaped rotor is mounted at one end of the engine drive shaft to produce electricity, and both the engine and alternator are mounted upon a transportable frame with mounting points for securing the generator inside the boat hull, such as below a deck of the boat.
In some applications, the rotor carries an arrangement of permanent magnets attached to an inner circumferential surface of the rotor. Preferably, the weight and position of the magnets are selected to balance firing impulses and radial accelerations of the engine and its rotating components.
In some cases, the alternator includes a stationary, wound stator responsive to the moving magnetic fields generated by the rotor, and packaged within the rotating rotor.
According to another aspect of the invention, a method of producing electrical power on-board a boat is provided. The method includes the steps of attaching a crankshaft of an outboard motor engine to an electrical generator, mounting the engine and generator on-board a boat, such as below deck, and running the engine to produce electrical power, and directing electrical power from the generator to a remote electrical load, such as an electrical appliance or on-board power grid, to perform useful work.
In some applications, the method also includes enclosing both the engine and generator in an enclosure.
In some cases, the engine and generator are mounted in side-by-side relation. In some other cases, the generator is mounted directly to the crankshaft at one end of the engine.
According to another aspect of my invention, an improved method of cooling marine power generation equipment is provided. Seawater is drawn from the body of water on which the boat floats, through a liquid-to-liquid heat exchanger, and then injected into a stream of exhaust before returning to the body of water. A liquid coolant is pumped along a closed path through the housing of the power generation equipment, where it absorbs heat generated by moving components within the housing, through the heat exchanger where it transfers the absorbed heat to the seawater, and then circulated back through the housing. This aspect of the invention can obtain particular advantage in combination with one or more of the aspects outlined above.
In some cases, the cooled power generation equipment comprises an outboard motor disposed rearward of a transom of the boat. In other cases, the cooled power generation equipment is mounted within the hull of the boat and employed either for propulsion or electrical power generation. In a particularly preferred example, the cooled power generation equipment comprises a vertically shafted combustion engine driving an electrical power generator mounted within the hull of a boat.
The circulated liquid coolant can be, for example, fresh water, ethylene glycol, or other liquid coolant known to be suitable for recirculating engine cooling.
Aspects of this invention can provide cost-effective electrical power generators of a physical size and power rating particularly needed by some boat owners, particularly those with moderate to low power requirements and who prefer a system that can be permanently mounted below deck and out of sight, rather than mounted outboard, for example, where they would be exposed to direct salt spray and less secure from theft. Furthermore, aspects of this invention can provide effective cooling of marine power equipment without requiring periodic flushing that is particularly undesirable for inboard equipment.
The details of one or more embodiments of the invention are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the invention will be apparent from the description and drawings, and from the claims.
DESCRIPTION OF DRAWINGS
FIGS. 1 and 2 illustrate an electrical power generator installed on board a boat.
FIG. 3 is a perspective view of the electrical power generator.
FIG. 4 is a schematic cross-sectional view of the generator, showing the side-by-side arrangement of vertically oriented engine and alternator.
FIG. 5 is a schematic cross-sectional view of a second embodiment of the generator, showing an in-line, vertical coupling of engine and alternator.
FIG. 6 is a schematic cross-sectional view of a third embodiment of the generator, showing an in-line, horizontal coupling of engine and alternator.
FIG. 7 shows an outboard marine motor cooled with recirculating coolant.
FIG. 8 shows an inboard marine engine-generator set cooled with seawater passed through a heat exchanger.
Like reference symbols in the various drawings indicate like elements.
DETAILED DESCRIPTION
Referring first to FIG. 1 , a boat 10 is equipped with an inboard, gasoline-powered engine 12 and an electric generator 14 , with both the engine and generator mounted below deck and accessible through a hatch as shown. Engine 12 and generator 14 may be fed from the same fuel tank (not shown), and exhaust through respective transom bulkhead exhaust ports 16 and 18 .
As shown in FIG. 2 , the generator 14 is mounted upon a platform 20 secured to the boat hull below the rear deck 22 . Platform 20 has appropriate mounting points (such as bolting bosses, tie-down features, or vibration-isolating mounting pads; not illustrated) for securing the generator to below-deck structure. Cooling water is suctioned from a seacock 24 through an inlet hose 26 , for injection into the exhaust stream of the generator engine as discussed in more detail below. Cooled exhaust gasses are routed through the transom 28 through an exhaust pipe 30 that rises to above the water line 32 . Generator 14 is controlled from a remote controller (e.g., switch panel 34 in FIG. 1 ), receiving input signals through electrical signal line 36 . Generated electrical power is routed to onboard electrical loads (e.g., appliances, air conditioners and such, not shown) via output cable 38 . The generator is powered by liquid fuel (e.g., gasoline or diesel fuel) from tank 40 , and a typical marine battery 41 provides 12VDC power.
Referring now to FIG. 3 , generator 14 forms a compact, readily mountable, practically stand-alone unit. The generator may be equipped with a sound-deadening enclosure 42 , as shown, or may alternately be mounted on a rigid frame 44 with open sides and top for increased air circulation. Details of a suitable enclosure 42 can be found in U.S. Pat. No. 5,929,394, the contents of which are incorporated by reference as if entirely set forth. Preferably the height “H” of the entire unit is less than about 15 inches or 38 centimeters (more preferably, less than about 12 inches or 30 centimeters), and occupies a footprint with a length “L” of less than about 25 inches or 63 centimeters (more preferably, less than about 20 inches or 50 centimeters), and a width “W” of less than about 15 inches or 38 centimeters (more preferably, less than about 12 inches or 30 centimeters). The weight of a 3 to 4 kilowatt unit is only about 120 pounds. Louvers 46 may be provided through enclosure 42 for increased air circulation, and the enclosure may optionally be equipped with output power receptacles 48 , as shown.
Turning to FIG. 4 , generator 14 contains a engine 50 coupled to an electric alternator 52 through a flexible timing or synchronous belt 54 and respective pulleys 56 and 58 . Belt 54 is of the type commonly used to drive camshafts in automotive engines, for example. Pulley 56 is mounted for rotation with one end of the vertical crankshaft 60 of engine 50 , with the other end of crankshaft 60 turning a positive displacement pump 62 for suctioning seawater from inlet hose 26 and pumping the seawater out through hose 64 into engine exhaust elbow 66 where it is injected into the exhaust stream of the engine to cool the exhaust before it enters muffler 68 .
In a presently preferred and commercially advantageous embodiment, engine 50 is a four-stroke gasoline engine designed for use in a vertical shaft configuration in outboard marine motors, and is therefore appropriate for marine environmental conditions. Such engines are typically already equipped with exhaust cooling elbow 66 and seawater pump 62 , and are therefore readily adapted for use in generator 14 by mounting the engine block to the generator frame, and supporting the lower end of crankshaft 60 in a frame-mounted bearing block 70 . For a generator 14 rated at about 3 to 4 kilowatts, a two cylinder, 15 horsepower outboard engine motor is suitable. For a generator 14 rated at only about 1–2 kilowatts, a one cylinder, 6 horsepower outboard engine motor is sufficient. As emissions regulations continue to encourage the replacement of two-stroke outboard motor engines with four-stroke versions, the cost and availability of appropriate engines suitable for use in my generator should continue to improve.
The overall height of the generator is kept advantageously low by arranging alternator 52 to occupy the same vertical space as engine 50 , with their shafts running parallel, spaced apart and vertical. The rotor shaft 72 of alternator 52 is mounted upon two spaced apart bearings (not shown) within the alternator housing, such that pulley 58 is mounted in cantilevered fashion at the end of the rotor shaft. In this example, alternator 52 is a permanent magnet alternator designed to be run at variable speed. Variable speed PM alternators are also known to be employed in wind machines and in some modern automotive systems, such as in hybrid vehicles.
Engine 50 may include a speed regulator to maintain the speed of the engine as close as possible to a speed selected with respect to the drive ratio to cause a synchronous alternator speed for producing a desired output frequency. For example, the engine may be speed-regulated about a 1500 RPM set point to cause a four-pole alternator to rotate at 1800 RPM for producing a 60 hertz output frequency. Such embodiments may require an increase in engine capacity over variable speed arrangements in order to maintain the speed and voltage within acceptable ranges over operational loads and temperatures, but advantageously do not require elaborate power conditioning circuitry.
Alternatively, generator controller 74 may include appropriate power-conditioning circuitry as is employed in variable speed, permanent magnet motor drivers, for accepting a wide range of raw power frequencies from alternator 52 and producing a desired output frequency. The cost of such circuitry will in some cases be sufficiently offset by the corresponding use of a smaller (lighter, less expensive) engine configured to operate at higher speeds in response to high load.
Other preferred features and aspects of controller 74 are disclosed in presently pending U.S. Ser. No. 09/368,200, filed Aug. 4, 1999 and incorporated herein by reference as if entirely set forth.
Referring to the embodiment of FIG. 5 , generator 14 ′ contains a vertically-shafted, four-stroke outboard engine motor 50 in which the standard flywheel at the end of its crankshaft has been replaced with a cup-shaped rotor 76 of a pancake profile, permanent magnet alternator 78 . Rotor 76 turns with the motor crankshaft and carries an arrangement of permanent magnets 80 attached to its inner circumferential surface. The weight and position of magnets 80 are selected to balance firing impulses and radial accelerations of the motor and its rotating components. Packaged within rotating rotor 76 is a stationary, wound stator 82 responsive to the moving magnetic fields generated by rotor 76 . This type of alternator can be constructed to have a very low profile or axial length, such that, replacing the flywheel of the motor, the motor-alternator combination can add only few inches to the height of the motor itself. Pump 62 may be mounted on the other end of the crankshaft, as shown, or can be electrically powered and mounted remotely for even lower package height.
The two above-described embodiments share the practical advantage of enabling the use of virtually unmodified outboard motor engines, which are produced in high quantity and therefore very reasonably priced. However, it is also possible to modify such engines for use in horizontally coupled configurations, as shown in FIG. 6 . In generator 14 ″, engine 50 ′ is mounted with its crankshaft 60 extending horizontally and coupled through a flexible coupling 82 to the rotor shaft of alternator 52 . Because engine 50 ′ was designed to operate with shaft 60 vertical, a few key modifications are made to ensure proper operation and reliability. First, engine 50 ′ is equipped with a bottom oil sump 84 with an appropriate internal oil pickup for siphoning lubricating oil up into the engine. For some outboard motor engines, other modifications may be required to keep oil from pooling on shaft seals, or collecting in internal passages and not returning properly to the sump. Second, carburetor 86 has been repositioned to maintain a vertical throat orientation as designed. In some cases, this entails installing a custom intake manifold designed for this purpose. Other necessary modifications will also be recognized and understood by those of ordinary skill, depending on the specific outboard motor engine selected for any given application.
Referring now to FIG. 7 , an outboard motor 88 has an exterior shell 90 shown in dashed outline. Within the shell a gasoline motor 92 turns a vertical drive shaft 94 that rotates a propeller 96 through a lower gearbox 98 . Gearbox 98 also turns a seawater pump 100 that pumps seawater up through conduit 102 into a high temperature side of a liquid-to-liquid heat exchanger 104 where it absorbs heat. From there, the warmed seawater is forced along conduit 106 into injection elbow 66 . The exhaust and injected seawater flow down along exhaust pipe 112 , and are ejected into the water below the water line. Meanwhile, liquid engine coolant (e.g., fresh water or ethylene glycol) is recirculated through motor 92 and heat exchanger 104 , where heat is extracted from the coolant. The coolant is motivated by pump 62 , which draws the coolant from a small reservoir 108 equipped with a fill cap 110 . Within heat exchanger 104 , the flows of seawater and coolant are maintained in their separation, such that they never mix. Because seawater never enters the housing of motor 92 , periodic flushing is not required and corrosion is reduced.
In FIG. 8 , the motor 50 ′ of generator 114 is equipped with a double pump 116 mounted to one end of its horizontal drive shaft. The outer half of pump 116 pumps seawater from inlet 26 through the hot side of heat exchanger 104 , and then into injection elbow 118 , where it is injected into the exhaust stream. The inner half of pump 116 pumps coolant from reservoir 108 through the housing of motor 50 ′, out along conduit 120 into the cold side of heat exchanger 104 , and then back into reservoir 108 , which is equipped with a pressure relief valve and an overflow tank 122 . A pressure expansion tank (not shown) may also be employed. As in the outboard motor cooling system of FIG. 7 , the two liquid flows are kept separate, and seawater never enters the housing of motor 50 ′. Thus, the motor housing can be advantageously cast of materials susceptible to corrosion from prolonged contact with salt water. Furthermore, generator 114 may be mounted in enclosed spaces below deck as no air flow is required for cooling.
Alternator 52 may be air-cooled, with either a separate air-seawater intercooler (not shown) included in enclosure 42 , or with the enclosure air circulated through heat exchanger 104 by a fan (not shown). Alternatively, alternator 52 may be liquid-cooled, either by passing the engine coolant through stator cooling tubes in the alternator, or with a separate coolant circuit that passes either through a dedicated cell of heat exchanger 104 or through a separate coolant-seawater intercooler (not shown). In any of these cases, all of the cooling seawater is preferably discharged into the exhaust at elbow 118 . The above-described alternator cooling arrangements may also be employed in cooling engine-generator sets configured with vertical drive shafts, such as shown in FIG. 4 . Details regarding a useful air-seawater intercooler can be found in my U.S. Pat. No. 5,014,660 and 5,125,378, the contents of both of which are incorporated by reference herein, as if set forth in their entirety.
A number of embodiments of the invention have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the invention. For example, the pulleys and belt of the embodiment of FIG. 4 can be arranged above the engine and alternator, with the seawater pump mounted below. Accordingly, other embodiments are within the scope of the following claims. | An on-board marine electrical power generator ( 14 ) containing a conventional four-stroke, water-cooled outboard motor engine ( 50 ) coupled to an alternator ( 52 ) upon a transportable frame ( 44 ) suitable for mounting on-board a boat. In one embodiment, the crankshaft ( 60 ) of the engine extends vertically and is coupled to a vertically oriented rotor ( 72 ) of the alternator, either directly or laterally spaced from the engine shaft. In another embodiment, the engine is modified for operation with its crankshaft extending horizontally. The physical size of the overall package is advantageously within a range suitable for installation on pleasure boats, even below deck. | 5 |
BACKGROUND OF THE INVENTION
1. Technical Field
The invention relates generally to an improved vehicle suspension system. More particularly, the invention relates to a vehicle suspension system with an improved alignment mechanism. Specifically, the invention relates to a mechanism for aligning an axle relative to the vehicle path of travel.
2. Background Information
The advent, following World War II of large load carrying capacity trucks and trailers in this country, created the need to provide a plurality of axles for increasing the capacity of trucks over that of the chassis-cab design which was manufactured with single front and rear axles. While multiple axles effectively increased carrying capacity, it was soon realized that as the number of load bearing axles increased on a given vehicle, a number of difficulties arose. Specifically, tire scuffing, loss in fuel economy and the inability to safely corner, all were problems associated with multiple axle vehicles. Mitigation of the these problems was, and continues to be, a primary concern of the industry which concern has resulted in the creation of a number of axle alignment mechanisms.
Trucks and trailers often employ suspension systems having trailing beams or rocker beams. Such suspensions generally include a longitudinally extending beam on both side of the vehicle which is pivotally connected at one end to a hanger bracket depending downwardly from the vehicle frame. The other end of the beam is generally associated with an inflatable air spring extending between the beam and the vehicle frame. The beams are generally parallel and spaced apart with an axle rigidly or resiliently attached to the beams and extending substantially normal thereto. One or more road engaging tires is then rotatably mounted on each end of the axle.
Most vehicles designed with the beam type suspension have a path of travel which is parallel to the frame rails extending longitudinally under the vehicle. For vehicles having only a front and a rear axle, the vehicle path of travel is generally defined by the parallel and spaced apart rear tires such that the direction of travel of the rear tires defines the path of travel of the vehicle. For vehicles having only a front and a rear axle, this path of travel is adequate and safe even if the rear tires are not positioned parallel with the vehicle frame rails. However, when multiple axles are utilized, the path of travel of each axle must be aligned with the line of travel of the remaining axles carried by the vehicle for safe economical vehicle operation. Specifically, if one axle is aligned with the longitudinal frame rails extending under the vehicle, and a second axle is offset relative to the longitudinal frame rails of the vehicle, as the vehicle moves over the road surface, one axle and its associated tire-wheel assemblies will track along the path of travel of the vehicle, while the second axle, which includes tire-wheel assemblies which do not rotate in a direction parallel to the path of travel of the vehicle, will drag under the vehicle increasing tire scuffing, tire wear, and creating a generally unsafe condition. When multiple axles are utilized, generally all tires affect the vehicle path of travel to some degree such that if one axle is offset relative to the vehicle path of travel, all tires will scuff, and drag under the vehicle. Additionally, as the tires are dragged along under the vehicle due to their misalignment, they continually add lateral forces to the suspension system, and consequently to the vehicle frame substantially reducing the lifespan of both the vehicle frame and suspension system components.
However, if the axles are aligned relative to the frame rails such that the tires rotate in a line parallel to the vehicle path of travel, the tire-wheel assemblies will rotate smoothly under the vehicle substantially increasing vehicle safety and vehicle performance as well as substantially increasing tire life.
For the above reasons, and specifically for safety and vehicle performance, it is necessary that each axle be carefully aligned with the vehicle, and with other load bearing axles carried by the vehicle to present a plurality of parallel and spaced apart tire-wheel assemblies for engaging the road surface and defining the precise direction of vehicle movement along the vehicle's path of travel. Such alignment is difficult for a number of reasons. Trailers as well as suspension systems may be manufactured out of tolerance, vehicle frame rails may not be perfectly parallel, and suspension systems may not be accurately mounted to the frame rails. These problems may be especially pronounced when suspension systems are added to existing equipment which may have experienced significant use.
Thus, to accommodate for the above inconsistencies in manufacturing and suspension system installation, an alignment mechanism may be included as part of the suspension system such that after the suspension system is installed on a vehicle, the axle may be moved relative to the vehicle to assure that the tire-wheel assemblies rotatably depending from the axle are substantially parallel to the vehicle path of travel. Axle alignment may be achieved by adjusting the axle mounting position relative to the parallel and spaced apart beams, or alternatively by adjusting the pivot point at which the beam is mounted to the hanger bracket.
While adjusting the axles relative to the beams is an adequate method of alignment, a number of problems are associated therewith. Specifically, such adjustment is often difficult to achieve as there is significant weight which must be moved up and down the beam to achieve the adjustment. Additionally, alignment of the axle relative to the beam often includes welding the mounting bracket to the beam after initial alignment. As such, it is difficult and expensive to realign the axle after the vehicle has been in service.
Similarly, previous alignment mechanisms which align the pivot point of the beam relative to the hanger bracket often required initial alignment of a collar within an elongated slot, which collar was welded in position after initial alignment. Once again, if the axle moved out of alignment, moving the collar previously welded to the hanger bracket is both difficult and expensive.
Thus, the need exists for an alignment mechanism which initially allows the axle to be aligned relative to the frame to assure that the tire-wheel assemblies rotatably depending from the axle are parallel to the vehicle path of travel. The need further exists for an axle alignment mechanism which will permit subsequent alignment of the axle relative to the vehicle frame without the need for cutting welds, or displacing the axle relative to the beams.
SUMMARY OF THE INVENTION
Objectives of the invention include providing a suspension system with an alignment mechanism for aligning an axle relative to a vehicle frame.
A further objective is to provide a suspension system with an alignment mechanism which permits both initial alignment of the axle relative to the vehicle, and subsequent alignment of the axle relative to the vehicle with relative ease.
Another objective is to provide an alignment mechanism which linearly displaces the pivotal connection between the beam and hanger bracket.
Still another objective of the invention is to provide an alignment mechanism for aligning an axle relative to a vehicle frame which is simple to operate.
Yet another objective of the invention is to provide a suspension system with an alignment mechanism which is of a simple construction, which achieves the stated objectives in a simple, effective and inexpensive manner, and which solves problems and satisfies needs existing in the art.
These and other objectives and advantages of the invention are obtained by the improved suspension systems, the general nature of which may be stated as including a pair of movable hanger brackets depending from the frame; a beam pivotally mounted to each movable hanger bracket; and alignment means for adjusting the position of each movable hanger bracket relative to the frame whereby the movable hanger bracket and pivotally mounted beam are movable between a first non-adjusted position and a second adjusted position.
BRIEF DESCRIPTION OF THE DRAWINGS
The preferred embodiments of the invention, illustrative of the best mode in which applicant has contemplated applying the principles, are set forth in the following description and are shown in the drawings and are particularly and distinctly pointed out and set forth in the appended claims.
FIG. 1 is a fragmentary side elevational view of the suspension system attached to a vehicle and shown with the tire-wheel assembly in dot-dash line;
FIG. 2 is an enlarged fragmentary sectional view taken along line 2--2, FIG. 1;
FIG. 3 is an enlarged fragmentary sectional view taken along line 3--3, FIG. 2;
FIG. 4 is a bottom plan view of a pair of suspension systems shown installed on a pair of fragmentary trailer frame rails shown in fragmentary, and shown with one suspension system in a non-aligned position;
FIG. 5 is a bottom plan view of a pair of suspension systems shown installed on a pair of trailer frame rails similar to FIG. 4, and shown with both suspension systems in an aligned position;
FIG. 6 is an enlarged fragmentary sectional view, similar to FIG. 3 but shown in an aligned position;
FIG. 7 is an enlarged fragmentary sectional view similar to FIG. 3 of a second embodiment of the present invention;
FIG. 8 is an enlarged fragmentary sectional view similar to FIG. 3 of a third embodiment of the present invention; and
FIG. 9 is an enlarged fragmentary sectional view similar to FIG. 3 of a fourth embodiment of the present invention.
Similar numerals refer to similar parts throughout the drawings.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The improved suspension system of the present invention is indicated generally at 1, and is particularly shown in FIG. 1 mounted on a trailer 2. Trailer 2 includes a cargo box 3 supported by a pair of frame rails 4 (one shown) extending longitudinally under the length of trailer 2. Suspension system 1 includes a pair of stationary hanger brackets 5 welded to a pair of parallel and spaced apart slide channels 6. Slide channels 6 are spaced apart a distance equal to the distance between frame rails 4 and are mounted to frame rails 4 with a plurality of mounting pins 7. While FIG. 1 shows a single suspension system 1 installed on trailer 2, it is understood that multiple suspension systems 1 may be installed under trailer 2 without departing from the spirit of the present invention.
Suspension system 1 includes a pair of parallel and spaced apart beams 10 (FIGS. 1 and 2). The first end of each beam 10 is mounted to a movable hanger bracket 11 at a pivot 12. An axle seat 13 is welded to a second end of each beam 10 for receiving an axle 14 which extends substantially perpendicular to beams 10. A U-bolt extends around each axle seat 13 and secures axle 14 to each beam 10. Each axle seat 13 is formed with an air spring mounting plate 16 whereby an air spring 17 is positioned intermediate each air spring mounting plate 16 and frame rails 4 for providing vertical load support for trailer 2. Axle 14 has a tire-wheel assembly 19 rotatably mounted on each end thereof.
In accordance with one of the main features of the present invention, and referring to FIGS. 1-3, each stationary hanger bracket 5 is formed with a forward compression plate 22, and a pair of parallel and spaced apart sidewalls 23 extending substantially perpendicular to compression plate 22. Similarly, each movable hanger bracket 11 is formed with an end plate 24, and a pair of parallel and spaced apart side plates 25 extending substantially perpendicular to end plate 24 and parallel to sidewalls 23 of stationary hanger brackets 5.
In accordance with another of the features of the present invention, each movable hanger bracket 11 is formed with a top end and a bottom end, and is positioned intermediate sidewalls 23 such that end plates 24 and compression plates 22 are substantially parallel and spaced apart. End plate 24 and side plate. 25 of each movable hanger bracket 11 are welded to a cylindrical sleeve, 26 (FIG. 3). A rubber bushing 27 is press-fit into each sleeve 26. Rubber bushings 27 are formed with a hole 28. An inner metal sleeve 31 is bonded to each rubber bushing 27 in holes 28 and is somewhat longer than sleeves 26 and rubber bushings 27, for purposes which will be described in detail hereinbelow. Each sidewall 23 is formed with a hole 32 which is axially aligned with an inner sleeve 31 whereby holes 32 and inner sleeves 31 receive a pair of pivot pins 33. Movable hanger brackets 11 are thus pivotally mounted on pivot pins 33 relative to stationary hanger brackets 5.
As discussed generally above, each beam 10 is mounted to a movable hanger bracket 11 at a pivot 12. Specifically, one end of each beam 10 is welded to a sleeve 34 which extends intermediate side plates 25. Each mounting sleeve 34 receives a rubber bushing 35 which is bonded to a pivot sleeve 36. Side plates 25 are formed with holes 37 axially aligned with pivot sleeve 36. Holes 37 and pivot sleeve 36 receive a mounting bolt 38. Spacer washers 41 (FIG. 2) are inserted over mounting bolt 38 and adjacent each side plate 25 to prevent lateral movement of beams 10 relative to movable hanger brackets 11.
Compression plates 22 of stationary hanger brackets 5 and end plates 24 of movable hanger brackets 11 are formed with axially aligned holes 42 for receiving a compression bolt 43 and nut 44. A washer 45 is interposed intermediate compression plate 22 and compression bolt 43 and similarly, a washer 46 is interposed intermediate nut 44 and end plate 24.
In accordance with one of the main features of the present invention, a spring 50 is positioned intermediate each compression plate 22 and end plate 24 which spring 50 may take the form of a bellville spring, a coil spring, a leaf spring or a compressed bushing. While any of the above springs may be positioned intermediate compression plate 22 and end plate 24 without departing of the spirit of the present invention, the preferred embodiment utilizes a high durometer bushing 51 having a hole 52 is positioned intermediate each compression plate 22 and end plate 24 with a compression bolt 43 extending through each hole 52. Additionally, a plastic washer extends around compression bolt 43 adjacent end plate 24. While bushings 51 may have a variety of sizes and configurations, in the preferred embodiment bushings 51 are square and are formed with a surface area to be positioned adjacent end plate 24 and compression plate 22 in the range of from 6 square inches to 25 square inches. Similarly, bushings 51 may be formed from an elastomeric material, a fabric reinforced rubber or urethane having a durometer in the range of from 50 to 90 Share A hardness but the durometer of bushing 51 is preferably 65 Share A hardness. Preferably, bushings 51 have a maximum deflection in the range of from 0.75 inches to 11/2 inches. As is apparent from a review of FIG. 3, when bushings 51 are manufactured of a lower durometer elastomeric material, they are somewhat larger to provide the necessary resistance as is described in detail hereinbelow. A gusset 55 extends intermediate side plates 25 and is welded to side plates 25 and end plate 24 to strengthen movable hanger brackets 11.
In operation, each movable hanger bracket 11 is rotatably supported on a pivot pin 33 with each inner sleeve 31 being clamped between sidewalls 23. Inasmuch as each inner sleeve 31 is clamped between sidewalls 23 and is longer than outer sleeve 26 and bushing 27, any lateral movement occurring between movable hanger bracket 11 and stationary hanger brackets 5 occurs as a result of lateral deflection of bushings 27 and is limited by the distance between sidewalls 23 and each outer sleeve 26. Similarly, rotational movement that occurs about pivot pins 33 is a result of radial deflection of elastomeric bushings 27.
Referring then to FIG. 4, a first suspension A is shown which is substantially axially aligned with the path of travel of trailer 2. However, a second suspension B is shown to be out of alignment with suspension system A and with the path of travel of trailer 2. Suspension system B may be out of alignment for a number of reasons. Suspension system B may have been incorrectly mounted to trailer 2, or alternatively due to manufacturing tolerances, suspension system B may have been manufactured such that if correctly mounted on trailer 2, it will remain out of alignment with other suspensions on trailer 2, and with the path of travel thereof. As can be seen from a review of FIG. 4, if trailer 2 is utilized with suspensions A and B as presently mounted, suspension system B will drag over the road surface, thus causing extensive tire wear, and possibly overstressing suspension components causing breakage.
Suspension system B may be brought into alignment with suspension system A by threading nut 44 onto compression bolt 43 thereby compressing elastomeric bushing 51. By compressing bushing 51, movable hanger bracket 11 will move from the position shown in FIGS. 3 and 4 to the position shown in FIGS. 5 and 6. The affected movable hanger bracket 11 will rotate about pivot pin 33 thus moving end plate 24 closer to compression plate 22. As elastomeric bushing 51 is compressed, interconnected beam 10 will be drawn toward compression plate 22 thus moving suspension system B from the position shown in FIG. 4 to the position shown in FIG. 5 and bringing suspension system B into alignment with suspension system A thereby substantially decreasing tire wear and removing significant stress from suspension components.
Bushing 51 is compressed intermediate end plate 24 of movable hanger bracket 11 and compression plate 25 of stationary hanger bracket 5. Bushing 51 thus must be manufactured of material of sufficient strength to apply an equal and opposite expansion force without deflection. Essentially, bushing 51 must be compressed via the threaded engagement of nut 44 on compression bolt 43 with a compressive force greater than the largest longitudinal load exerted on bushing 51. Longitudinal loads are exerted on bushing 51 when, for example, the tire-wheel assembly 19 strikes a curb, engages the edge of a pothole, or when brakes are applied to the trailer. In all these situations, a longitudinal load is transferred from the tire-wheel assemblies 19 through U-bolts 15 and axle seats 13 into beams 10. This force is transferred from beams 10 to movable hanger brackets 11, and consequentially acts upon elastomeric bushings 51. As such, the longitudinal forces acting through beams 10 are the primary forces which act upon bushings 51. Forces acting upon elastomeric bushings 51 are in the range of from 6,000 pounds to 10,000 pounds. To assure that bushing 51 will not deflect as a result of longitudinal forces acting through suspension system 1, bushings 51 are compressed such that the responding force is greater than 10,000 pounds, or greater than the maximum force felt by the suspension system as a result of longitudinal forces acting through beams 10 and movable hanger brackets 11.
Once bushing 51 is compressed, for example when in the position shown in FIG. 6, compressive forces acting on bushing 51 are extremely high when compared to the longitudinal forces acting on the bushing as a result of trailer travel such that such longitudinal forces, even at maximum are insufficient to deflect bushing 51. Bushing 51 thus is essentially a solid, non-flexible element of suspension system 1.
As can be seen from a review of FIG. 6, pivot 12 is positioned intermediate pivot pin 33 and compression bolt 43. As a result, bushings 51 will deflect a greater distance than the axial displacement of associated beam 10 as beam 10 is attached to movable hanger bracket 11 adjacent pivot pin 33 such that beam 10 travels through a smaller arc, and thus a shorter linear distance than that portion of movable hanger bracket 11 adjacent bushing 51.
Referring to a second embodiment of the present invention indicated generally at 58 in FIG. 7, a pair of movable hanger brackets 54 are mounted to a pair of stationary hanger brackets 57 on a pair of pivot pins 56 adjacent the top of hanger brackets 54. Each beam 10 is mounted to a movable hanger bracket 54 in a manner substantially identical to the first embodiment of the present invention adjacent the bottom end of each movable hanger bracket 54. However, compression bolts 43 and bushings 51 are positioned intermediate each beam 10 and pivot pin 56. Bushings 51 thus deflects less than the longitudinal displacement of beams 10 relative to stationary hanger brackets 57 as beams 10 rotate about pivot pins 56 through a lever arm longer than the lever arm which acts upon bushing 51.
A third embodiment of the suspension system of the present invention is indicated generally at 60 and is shown particularly in FIG. 8. Suspension system 60 is substantially identical to suspension systems 1 and 58 of the first and second embodiments of the present invention, and includes a pair of pivot pins 61 similar to pivot pins 33, a pair of compression bolts 43, a pair of nuts 44 and a pair of bushings 51. Suspension system 60 further includes a pair of movable hanger brackets 64 and a pair of stationary hanger brackets 65, as well as a pair of pivot pins 61. Suspension system 60 differs from suspension system 1 only in that suspension system 60 provides that bushings 51 are mounted adjacent the top end of each movable hanger bracket 64 while suspension system 1 provides that bushings 51 are mounted adjacent the bottom end of movable hanger brackets 11.
A fourth embodiment of the present invention (FIG. 9) is indicated generally at 70 and includes compression bolts 43, bushings 51, beams 10, a pair of movable hanger brackets 74, and a pair of stationary hanger brackets 75, each formed with a compression plate 76. Additionally, a pivot pin 77 pivotally attaches each movable hanger bracket 74 to each stationary hanger bracket 75. Suspension system 70 is substantially similar to suspension system 60, 58 and 1 except that each pivot pin 77 is positioned intermediate beam 10 and compression bolt 43 such that when each flexible bushing 51 is compressed, the upper portion of movable hanger bracket 74 is moved toward compression plate 76 of stationary hanger bracket 75, while beam 10 is moved away from compression plate 76 of hanger bracket 75.
As is appreciated from a review of FIGS. 6-9, all four embodiments of the present invention operate similarly, with the position of the pivot pin, beam and flexible bushing operating to increase or decrease the longitudinal movement of the beam relative to a bushing deflection.
In summary, the present invention provides a suspension system having an alignment mechanism which utilizes a flexible bushing compressed with a force substantially higher than the largest longitudinal force experienced by the bushing. This bushing may be further compressed or relaxed to reposition the axle, and interconnected tire-wheel assemblies to assure that the same are aligned with the trailer's path of travel to prevent tire scuffing and to substantially increase the life of suspension components. Additionally, the compression bolt may be periodically adjusted without the need for complicated alignment procedures to assure that as suspension components wear, suspension system 1 may remain aligned with the path of travel of trailer 2.
Accordingly, the improved vehicle suspension system with alignment is simplified, provides an effective, safe, inexpensive, and efficient device which achieves all the enumerated objectives, provides for eliminating difficulties encountered with prior devices, and solves problems and obtains new results in the art.
In the foregoing description, certain terms have been used for brevity, clearness and understanding; but no unnecessary limitations are to be implied therefrom beyond the requirement of the prior art, because such terms are used for descriptive purposes and are intended to be broadly construed.
Moreover, the description and illustration of the invention is by way of example, and the scope of the invention is not limited to the exact details shown or described.
Having now described the features, discoveries and principles of the invention, the manner in which the improved vehicle suspension system with alignment is constructed and used, the characteristics of the construction, and the advantageous, new and useful results obtained; the new and useful structures, devices, elements, arrangements, parts and combinations, are set forth in the appended claims. | A suspension system for mounting to a vehicle frame includes a pair of stationary hanger brackets each formed with a compression plate and a pair of sidewalls. A movable hanger bracket is pivotally mounted on a pivot pin intermediate the sidewalls of the stationary hanger bracket, and a beam is pivotally mounted to each movable hanger bracket. An axle extends substantially perpendicular to the beams, and is rigidly attached thereto. An elastomeric bushing is positioned intermediate the movable hanger bracket and the stationary hanger bracket with a compression bolt extending therethrough. A nut threadably engages the compression bolt to draw the movable hanger bracket toward the compression plate thereby applying a compressive force to the elastomeric bushing. As the bushing compresses and the movable hanger bracket moves toward the compression plate of the stationary hanger bracket, the beam is similarly pulled toward the compression plate of the stationary hanger bracket thereby aligning the beam and interconnected axle with the vehicle path of travel. The compression bolt may be adjusted periodically as the trailer ages through use. | 1 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. Utility application Ser. No. 12/255,951, filed Oct. 22, 2008 the contents of which is hereby incorporated by reference in its entirety.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] One or more embodiments of the invention relate to compositions and method for synthesizing the navel orangeworm pheromones and methods for using thereof for pest management.
[0004] 2. Description of the Related Art
[0005] As the need for food production in the world grows so does the need for new forms of pest control. The increasing use of conventional pesticides leads to resistant pests, severely alters the natural ecology, and damages the environment. This problem has led to innovative ways in pest management without the use of pesticides. One of the ways that has been presented is the use of insect sex pheromones (Shani, A., “Integrated pest management using pheromones,” Chemtech 28(3), pp. 30-35 (1998)).
[0006] Sex pheromones are used in the chemical communication of many insects for attracting the species of the opposite sex to engage in reproduction. Pheromones are useful for pest control largely through four means: monitoring, mass trappings, attract and kill, and disruption of communication or confusion. “Monitoring” methodology attracts the pests to a central area, which allows the grower to obtain precise information on the size of the pest population in order to make informed decisions on pesticide use or non-use. “Mass trappings” brings the pest to a common area and physically trap them, which hinder production of new generations of pests. “Attract and kill” allows the pests to be drawn into a centrally located container and killed in the container by the pesticide reducing the need to spread pesticides in broad areas. “Disruption of communication” can occur in that a large concentration of sex pheromone can mask naturally occurring pheromones or saturate the receptors in the insect causing confusion and disruption of natural reproductive means (Shani, 1998). For each one of these means, each individual species of pest needs to be treated with a tailor-made composition which can add substantially to the cost in creating a bulk amount.
[0007] Pheromones are considered relatively non-toxic, not environmentally persistent (decompose quickly in nature), and do not create resistance by pests. These qualities make them a superior choice as an alternative to pesticides. Because of the need for more environmentally friendly pest management, the industry has emphasis to develop more efficient and cost-effective production methods for the pheromones while utilizing more environmentally benign methods for their production.
[0008] One of the more pervasive pests in agriculture areas of tree-nut production is the larval worm of the moth family Lepidoptera: class Pyralidae known as the Navel Orangeworm, Amyelosis transitella . The tree-nut industry is a multi-billion dollar industry but estimates show only 1% of the cultivated land uses pheromones for pest control (Shani, 1998). With a relatively high cost for producing the pheromones, the economic impact creates a strong need to create an efficient method to produce the sex pheromone of the navel orangeworm.
[0009] One of the major sex pheromone of the navel orangeworm has been isolated and analyzed is (Z,Z)-11,13-hexadecadienal (HDAL). This pheromone and others have been described in studies and belongs in the Ando type I pheromones (Ando T. et al., “Lepidopteran sex pheromones,” Top Curr Chem 239: 51-96, 2004). HDAL has been shown in other studies to have a high affinity for binding to a major pheromone binding protein (AtraPBP) which can correlate to having some effect on the mating disruption and monitoring of the adult moths (Leal et al., “Unusual pheromone chemistry in the navel orangeworm: novel sex attractants and a behavioral antagonist,” Naturewissenshaften 92:139-146 (2005)).
[0010] A method of synthesis for HDAL was described in a 1980 publication that described an at least seven step method (Sonnett, P. E. and R. R. Heath, “Stereospecific synthesis of (Z,Z)-11,13-hexadienal, a Female Sex Pheromone of the Navel Orangeworm, Amyelosis transitella , (Lepidoptera:Pyralidae)” Journal of Chemical Ecology, 6,221-228, 1980). U.S. Pat. Nos. 4,198,533 and 4,228,093 describe similar seven or more reaction step methods. Some of the problems faced by industry in the process of making pheromones, include use of toxic reagents, lack of available refined starting materials on the market, and inefficiencies in the processes. There is need for new and better methods for synthesizing the navel orangeworm pheromones.
[0011] To the best of knowledge known at the time of the patent application, the improved methods herein for creating a synthetic composition of the navel orangeworm pheromone for use in pest management have not been described.
BRIEF SUMMARY OF THE INVENTION
[0012] One or more embodiments of the present invention are novel and improved methods for synthesizing a sex pheromone of the navel orangeworm using a reduced number of the presently used seven synthetic steps. Among other benefits these novel pheromone synthetic routes have improved stability of reactants and intermediates.
[0013] Accordingly one or more embodiments of the invention provide methods for forming various intermediates and final products including a starting material such as a halo substituted alkyl alcohol. From this starting material, a step includes forming a halo substituted alkanal. Another step includes forming a halo substituted dialkoxy substituted alkyl. Another step includes forming a dialkyloxy substituted alkynyl. Yet another step includes forming a halo substituted alkynyl. Another step includes forming dialkoxy substituted diynyl. A final step includes forming the final pheromone.
[0014] In other embodiments of the invention provides for methods of reacting the intermediate products to form the final pheromone product. The step on the starting material is an oxidation to form the next intermediate product. Another step is an O-alkyl-C-alkoxy addition that forms the next intermediate product. Another step is an alkynyl-de-halogenation to form the next intermediate product. Yet another step is a halogenation to form the next intermediate product. Another step is performing a cycle of oxidative addition and reductive elimination to form the next intermediate product. And the final step is a reduction and hydrolysis to form the cis-cis isomer of the pheromone.
[0015] Other embodiments of the invention provide for methods of forming the (Z,Z)-11,13-hexadecadienal, utilizing intermediate products in less than seven steps. The starting material in this embodiment utilizes 10-chlorodecan-1-ol. The next step utilizes 10-chlorondecanal. Another step utilizes 10-chloro-1,1-diethoxydecane. Another step utilizes but-1-yne. Yet another step utilizes both 12,12-diethoxydodec-1-yne and 1-bromobut-1-yne. Another step utilizes 16,16-diethoxyhexadeca-3,5-diyne to form the final pheromone.
[0016] Other embodiments of the invention provide for methods of forming the (Z,Z)-11,13-hexadecadienal utilizing various reagents. Accordingly, these reagents sodium bromide, sodium acetate, 2,2,6,6-tetramethylpiperidinooxy (TEMPO), ethyl acetate, and sodium hypochlorite are used on the starting material for the first step. The next step utilizes p-toluenesulfonic acid monohydrate and triethylorthoformate to form the next intermediate product. Another step utilizes reagents lithium acetylide, ethylenediamine complex and sodium iodide in dimethylsulfoxide to form another intermediate product. Another step utilizes reagents potassium hydroxide in water additionally with bromide to form a reactant. Yet another step includes hydroxylamine hydrochloride, copper (I) chloride in methanol and added to with n-propylamine to form yet another intermediate product. And the final step utilizes reagents of cyclohexene and borane-N,N-diethylaniline complex (DEANB) in tetrahydrofuran, glacial acetic acid and either aqueous sulfuric acid or metal tetrafluorborate complexes.
[0017] Other embodiments of the invention provide for forming the stable version of the navel orangeworm pheromone (Z,Z)-11,13-hexadecadienal by utilizing a method of less than six synthetic steps. Similarly, the embodiment provides a method for performing an oxidation on a starting material preferably 10-chlorodecan-1-ol to form the aldehyde. Another step protects the aldehyde by utilizing a C-alkyoxy O-alkyl addition procedure. From this intermediate product, the compound is reacted with a terminal alkyne preferably 1,3-hexadiyne that was optionally formed from an internal alkyne such as 2,4-hexadiyne by use of a nucleophilic addition to form the next intermediate product, 16,16-diethoxyhexadeca-3,5-diyne. This compound then undergoes a further reaction in the method to stereospecifically reduce the diyne moiety and de-protect the aldehyde to create the final pheromone. It is contemplated not using the optional step of forming the terminal alkyne but utilizing a commercially available compound allowing for a method of less than five synthetic steps.
[0018] The embodiments of the invention provide for steps utilizing reagents of alkali metal amides such as sodium amide in an ether to optionally rearrange the internal alkyne to a terminal alkyne and to form the next intermediate product.
[0019] Another embodiment of the invention provide for a synthesis kit that utilizes all synthetic reagents, starting materials, methods, and apparatuses for forming the (Z,Z)-11,13-hexadecadienal, navel orangeworm sex pheromone.
[0020] These and other embodiments of the present invention will readily occur to those of ordinary skill in the art in view of this disclosure.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] The above and other aspects, features and advantages of the invention will be more apparent from the following more particular description thereof, presented in conjunction with the following drawings wherein:
[0022] FIG. 1 is the outlined reaction scheme of the synthetic method for making the navel orangeworm sex pheromone. After step B, the reaction scheme diverges into two alternative pathways. The numbers in parentheses designate the formula directly adjacent to it. The letters in parentheses designate the reaction step to which the arrows connote.
[0023] FIG. 2 is the outlined reaction scheme of the synthetic method shown in FIG. 1 Pathway I also named Scheme 1a.
[0024] FIG. 3 is the outlined reaction scheme of the synthetic method shown in FIG. 1 Pathway II also named Scheme 1b.
[0025] FIG. 4 is the GC chromatograph of the Example 1 compound 7 (Z,Z)-11,13-hexadecadienal.
[0026] FIG. 5 is the GC chromatograph of a reference standard (Z,Z)-11,13-hexadecadienal.
[0027] FIG. 6 is a schematic diagram of an oxidative addition and reductive elimination reaction.
[0028] FIG. 7 is a synthetic scheme for Example 1.
DETAILED DESCRIPTION
[0029] A synthetic pheromone composition will now be described. In the following exemplary description numerous specific details are set forth in order to provide a more thorough understanding of embodiments of the invention. It will be apparent, however, to an artisan of ordinary skill that the present invention may be practiced without incorporating all aspects of the specific details described herein. In other instances, specific features, quantities, or measurements well known to those of ordinary skill in the art have not been described in detail so as not to obscure the invention. Readers should note that although examples of the invention are set forth herein, the claims, and the full scope of any equivalents, are what define the metes and bounds of the invention.
[0030] The practice of the present invention will employ unless otherwise indicated conventional methods of chemistry within the skill of the art. Such techniques, methods, reactions, and the like are explained fully in the literature such as Advanced Organic Chemistry: Reactions, Mechanisms, and structure, Ed. Jerry March 4th ed. (New York, John Wiley and sons, 1985) and Techniques and Experiments for Organic Chemistry, Addison Ault, 5th ed. (University press, 1998).
[0031] All publications and patents and patent applications cited herein are hereby incorporated by reference in their entirety.
[0032] As used in this specification and in the appended claims, the singular forms “a,” “an” and “the” include plural references unless the content clearly dictates otherwise.
[0033] The use of the word “preferably” in its various forms is for ease of reading and should not be used to read into the claims anything more.
[0034] In describing the invention and embodiments, the following terms will be employed and are intended to be defined as indicated below. If any terms are not fully defined, then the normal usage as used in the art will fill any gaps in the understanding of the terminology.
[0035] The term “substitution” is a replacement of an atom or group of atoms in a moiety by another atom or group of atoms.
[0036] The term “substituted” means that the specified group or moiety bears one or more substituents. The term “unsubstituted” means that the specified group bears no substituents. The term “optionally substituted” means that the specified group is unsubstituted or substituted by one or more substituents. It is to be understood that in the compounds of the present invention when a group is said to be “unsubstituted,” or is “substituted” with fewer groups than would fill the valencies of all the atoms in the compound, the remaining valencies on such a group are filled by hydrogen. For example, if a terminal ethyl group is substituted with one additional substituent, one of ordinary skill in the art would understand that such a group has 4 open positions left on carbon atoms. (8 initial positions, minus two for the C—C bond, minus one to which the remainder of the compound is bonded, minus an additional substituent, to leave 4 open positions). Similarly, if an ethyl group in the present compounds is said to be “disubstituted,” one of ordinary skill in the art would understand it to mean that the terminal ethyl group has 3 open positions left on the carbon atoms.
[0037] The term “reduction” is when a reductant or atom gains an electron, though there may be no shift of electrons, to decrease the oxidation content of the final product or atom. For example in a simple reaction:
[0000]
[0000] in this example R and R′ are alkyl, and H is a generalized reducing agent.
[0038] The term “oxidation” is when an oxidant or atom loses an electron, though there may be no shift of electrons, to increase the oxidation content of the final product or atom. For example in a simple reaction:
[0000]
[0000] in this example R and R′ are alkyl and O is a generalized oxidizing agent.
[0039] The term “TEMPO oxidation” is utilizing 2,2,6,6-Tetramethylpiperidinyloxy as a stable nitroxyl radical, which serves in an oxidation reaction as a catalyst. It allows for environmentally benign reactions that are good alternatives to chromium based reagents. An example of a TEMPO oxidation would be the catalyst mixed with a starting material with a metal halide, metal acetate, and metal halogenate kept at controlled concentrations and stirred at a temperature lower than ambient for less than 3 h.
[0040] The term “halogenation” is a reaction of an alkyl group with molecular halogen. A hydrogen atom in the alkyl group is substituted by a halogen atom. Reversing the substitution to replace the halogen with a hydrogen or a moiety of a carbon-alkyl group is termed “de-halogenation.” For halogenation example in simple reaction:
[0000]
[0041] For this example R is alkyl group and X is halogen.
[0042] For a de-halogenation (Alkyl de-halogenation) example:
[0000]
[0043] For this example R and R′ are alkyl groups and X is halogen.
[0044] The named “Cadiot Chodkiewicz” reaction utilizes a copper (I)-catalyzed coupling of a terminal alkyne and an alkynyl halide which offers access to an unsymmetircial diynyl (Cadiot, P.; Chodkiewicz, W. Chemistry of Acetylenes ; Viehe, H. G., Ed.; Marcel Dekker: New York, 1969; pp 597-647). An example of the reaction is in this simple scheme:
[0000]
[0045] In this example R and R′ are Alkyl groups.
[0046] The term “oxidative addition” is used in transitional metals catalyzed, organometallic reactions when there is an addition of a sigma bond to a metal. The oxidation state of the metal changes +2. See FIG. 6 for a schematic example. In this example R and R′ are alkyl groups, and X is a halogen.
[0047] The term “reductive elimination” used in transitional metals catalyzed, organometallic reactions is the reverse of oxidative addition where there is a disassociation of a sigma bond to reform the original organometallic complex. The oxidation state of the metal changes −2. See FIG. 6 for a schematic example. In this example R and R′ are alkyl groups, and X is a halogen.
[0048] The term “addition” is used referring to an unsaturated molecule with a double bond which can undergo a reaction whereby a pair of electrons is removed from the double bond (for example) and is used to attach new groups to the molecule. For example, an O-Alkyl-C-alkoxy addition transforms the aldehyde into an acetal (also called herein an acetalization) as in this simple example:
[0000]
[0049] In this example R and R′ are Alkyl groups. The term “nucleophilic addition” is an addition reaction wherein a chemical compound a π bond is removed by the creation of two new covalent bonds by the addition of a nucleophile. The nucleophile can be an anion or free electrons seeking an electrophile such as a proton. For example:
R—C≡C—C≡C—H+NaNH 2 →R—C≡C—C≡C: (−) Na (+) +NH3→R—C≡C—C≡C—Na+X—R′→R—C≡C—C≡C—R′
[0050] R and R′ are alkyl groups and X is a halogen.
[0051] In this example, because the acetylide anion is a powerful nucleophile it may displace the halide ion from the primary alkyl halide to give a substituted dialkynyl as a product.
[0052] The term triple bond migration rearrangement also called an isomerization is the process by which one molecule is transformation into another molecule which has exactly the same atoms, but wherein these atoms are rearranged. When the isomerisation occurs intramolecularly it is considered a rearrangement reaction which is an organic reaction where the carbon skeleton of a molecule is rearranged to give a structural isomer of the original molecule. For example:
[0000]
[0000] The term “hydrolysis” is used as the reverse or opposite of “condensation,” a reaction in which two molecular fragments are joined for each water molecule produced. Thus, the two joined molecular fragments are reacted with water usually in the presence of an acid to break the fragments into separate fragments. A simple example is:
[0000]
[0053] In this example R and R′ are Alkyl. The terms “cis” (Z) and “trans” (E) are also referred to as geometric stereoisomers with configurations relative to a C═C moiety. “Cis” also known as Z in nomenclature configures the carbons on a geometric plane to have the constituents of the substituted carbons on the same side of the plane as seen in the example of 2-butene. For example;
[0000]
[0054] Conversely, “trans” also known as E in nomenclature configures the carbons on a geometric plane to have the on opposite sides of the plane as seen in the example of trans-2-butene. For example;
[0000]
[0055] The term “environmentally benign” refers to using chemicals in synthetic reactions that create less of a burden on the environment. This includes but is not limited to the physical environment, the personal working environment, and the like. For example, for the physical environment, the issues in hazardous waste disposal of heavy metals and in the personal working environment, exposure to toxic chemicals being used or created by the worker or in odor concentration threshold nuisances.
[0056] The term “ambient temperature” is the normal temperature of the air and or environment around the process being performed usually between the temperature of 20° C. and 27° C. without any abnormal heat source being applied.
[0057] The term “starting material” is the compounds that are used to be reactants in each reaction step. This can be used interchangeably with intermediate products when it makes sense. For example, if a compound is having a reaction performed on it, it is a reactant and starting material. If a compound is the result of the reaction then it is not a starting material but could become a starting material if it is used in a subsequent reaction step.
[0058] The term “protecting group” is a chemical modification of a functional group moiety in order to obtain chemoselectivity in a subsequent chemical reaction of a multi-step organic synthesis. Conversely, when the protecting group is removed to allow for the functional group to be activated, this is called deprotection. For example, a compound with a terminal aldehyde is transformed into an acetal in order that the aldehyde is not available for synthetic modification in a subsequent synthetic step that could modify an un-protected aldehyde. After the subsequent synthetic step, the acetal is transformed back to the terminal aldehyde and is available as a functional group.
[0059] The terms “oxy” or “oxo” is an oxygen or a moiety that has a substituent of oxygen.
[0060] The terms “halo” and/or “halogen” refer to fluorine, chlorine, bromine or iodine.
[0061] The term “halide” is a binary compound, of which one part is a halogen atom and the other part is an element or radical that is less electronegative than the halogen, to make a fluoride, chloride, bromide, and iodide.
[0062] The term “acetal” refers to a carbon atom that is substituted with two single bonded oxygens such as an alkoxy moiety.
[0063] The term “aldehyde” refers to a terminal carbon atom bonded to a hydrogen atom and double bonded to an oxygen atom.
[0064] The term “alkyl” refers to a saturated aliphatic hydrocarbon radical including straight chain and branched chain groups of 1 to 16 carbon atoms. Examples of (C 1 to C 6 ) alkyl groups include methyl, ethyl, propyl, 2-propyl, n-butyl, iso-butyl, tent-butyl, pentyl, hexyl, and the like.
[0065] The term “alkenyl” means an alkyl moiety comprising 2 to 16 carbons having at least one carbon-carbon double bond. The carbon-carbon double bond in such a group may be anywhere along the 2 to 16 carbon chain that will result in a stable compound. Such groups could include both the E and Z isomers of said alkenyl moiety. Examples of such groups include, but are not limited to, ethenyl, propenyl, butenyl, allyl, and pentenyl.
[0066] As used herein, the term “alkynyl” means an alkyl moiety comprising from 2 to 16 carbon atoms and having at least one carbon-carbon triple bond. The carbon-carbon triple bond in such a group may be anywhere along the 2 to 16 carbon chain that will result in a stable compound. An “internal alkynyl” is when a triple bonded carbon pair is found at some position on the carbon chain that is not an end of the carbon chain. Conversely, a “terminal alkynyl” is when a triple bonded carbon pair is found at an end of the carbon chain. Examples of such groups include, but are not limited to, ethyne, propyne, 1-butyne, 2-butyne, 1-pentyne, 2-pentyne, 1-hexyne, 2-hexyne, and 3-hexyne.
[0067] The term “alkanal” means an alkyl moiety comprising 2 to 16 carbons having an aldehyde on a terminal end.
[0068] The term “alkenal” means an alkenyl moiety comprising of 2 to 16 carbons having an aldehyde on a terminal end.
[0069] As used herein, the term “diynyl” means an alkyl moiety comprising from 4 to 16 carbon atoms and having at least two carbon-carbon triple bonds. The carbon-carbon triple bond in such a group may be anywhere along the 4 to 16 carbon chain that will result in a stable compound.
[0070] The term “alkoxy”, as used herein, means an O-alkyl group wherein said alkyl group contains from 1 to 16 carbon atoms and is straight, branched, or cyclic. Examples of such groups include, but are not limited to, methoxy, ethoxy, n-propyloxy, iso-propyloxy, n-butoxy, iso-butoxy, tert-butoxy, cyclopentyloxy, and cyclohexyloxy.
[0071] The term “cycloalkenyl” means an unsaturated, monocyclic ring structure having a total of from 5 to 8 carbon ring atoms with at least one C═C double bond in the cycle. Examples of such groups include, but not limited to, cyclopentenyl, cyclohexenyl.
[0072] According to one or more embodiments of the invention, methods of synthesis for the navel orangeworm pheromone are shown in FIG. 1 , scheme 1. According to embodiments of the invention shown in FIG. 2 , scheme 1a that generally follows pathway I of scheme 1, a step A is a reaction using compound of formula 1
[0000]
[0000] a step B is a reaction using compound of formula 2
[0000]
[0000] a step C is a reaction using compound of formula 3
[0000]
[0000] step D is a reaction using compound of formula 5a
[0000]
[0000] a step E is a reaction using compound of formula 4
[0000]
[0000] and using compound of formula 5b
[0000]
[0000] a step F is a reaction using compound of formula 6
[0000]
[0000] to form the final compound of formula 7
[0000]
[0000] wherein: X and X′ is halogen; Y is —OH; Y′ is ═O; R 1 is [—CH 2 — m , alkyl; R 2 and R 4 are —C≡CH, alkynyl; R 3 is CH 3 —[CH 2 ] n —, alkyl; R 5 is [—C≡C—] p , alkynyl, R 6 is [—C≡C—] q , alkynyl R 7 is —C═C—C═C—, alkenyl, R 8 , W is —O-alkyl, —O—R 3 , —O—CH 2 —CH 3 ; R 8 is the geometric cis configuration represented by structure
[0000]
[0000] m is independently 5,6,7,8,9,10,11,12; n is independently 1,2,3; p is independently 1,2; and q is independently 1,2.
[0073] Another embodiment of the invention is when X is chlorine; X′ is bromine; R 1 is [—CH 2 —] m ; R 2 is —CCH; R 3 is CH 3 —[CH 2 ] n —; R 4 is —C≡CH; R 5 is [—C≡C—] p ; R 6 is [—C≡C—] q ; R 7 is R 8 ; R is the geometric cis configuration represented by structure
[0000]
W is —O—CH 2 —CH 3 ; m is 10; n is 1; p is 1; q is 2.
[0074] In that the steps of FIG. 2 , scheme 1a, and FIG. 3 , scheme 1b, have similar overlapping steps, those steps have been given similar lettering and numbering for ease of following the synthetic pathways. Where the two pathways diverge other letters and numbers are used to show those sequence of steps. The alphabetical and numerical order is to be used as it makes sense in the schemes shown but is not necessarily in normal alphabetical or numerical order as seen in the pathways. According to the embodiments of the invention shown in FIG. 3 , scheme 1b, that generally follows the pathway II of scheme 1, a step A is a reaction using compound of formula 1
[0000]
[0000] a step B is a reaction using compound of formula 2
[0000]
[0000] a step G is an optional reaction using compound of formula 8a
[0000]
[0000] step H is a reaction using compound of formula 3
[0000]
[0000] and compound of formula 8b
[0000]
[0000] and step F is a reaction using compound of formula 6
[0000]
[0000] to form the final compound of formula 7
[0000]
[0000] wherein: X is halogen; Y is —OH; Y′ is ═O; R 1 is [—CH 2 —] m , or alkyl; R 3 is CH 3 —[CH 2 ] n —, or alkyl; R 5 is [—C≡C—] p , or alkynyl; R 6 is [—C≡C—] q , or alkynyl; R 7 is —C═C—C═C—, alkenyl, or R 8 ; W is —O-alkyl, —O—R 3 , or —O—CH 2 —CH 3 ; R 8 is the geometric cis configuration represented by structure
[0000]
[0000] R 9 is —CH 3 , or alkyl; R 10 is ≡C (−) , carbon anion, or de-protonated carbon; M is a metal, such as but not limited to sodium, lithium, potassium, magnesium, wherein M and R 10 together may form a salt; m is independently 5, 6,7,8,9,10,11 or 12; n is independently 1,2 or 3; p is independently 1 or 2; q is independently 1 or 2.
[0075] Another embodiment of the invention is when X is chlorine; R 1 is [—CH 2 —] m ; R 2 is —C≡CH; R 3 is CH 3 —[CH 2 ] n —; R 5 is [—C≡C—] p ; R 6 is [—C≡C—] q ; R 7 is R 8 ; W is —O—CH 2 —CH 3 ; R 8 is the geometric cis configuration represented by structure
[0000]
[0000] R 9 is —CH 3 , R 10 is ≡C (−) ; M is sodium; m is 10; n is 1; p is 1; q is 2.
[0076] Other embodiments of the invention are described in the following steps.
Scheme 1: Step A:
[0077] In the method of synthesis shown in FIG. 1 , scheme 1, according to embodiments of the invention, the compound of formula (1) which is generally known and commonly acquired is reacted to form compound of formula (2), preferably using an oxidation reaction and most preferably using a TEMPO oxidation. The compound of formula (1) is preferably a halo substituted alkyl alcohol, most preferably 10-chlorodecan-1-ol, and compound of formula (2) is preferably a halo substituted alkanal, most preferably 10-chlorodecan-1-al.
[0078] The method of synthesis shown in FIG. 1 , scheme 1-step A according to embodiments of the invention is carried out using various diluents. Suitable diluents are virtually all inert organic solvents. These preferably include aliphatic, aromatic, and optionally halogenated hydrocarbons such as pentane, hexane, heptane, cyclohexane, petroleum ether, benzene, ligroin, benzene, toluene, xylene, methylene chloride, ethylene chloride, chloroform, carbon tetrachloride, chlorobenzene, and o-dichlorobenzene, ethers, such as diethyl ether, dibutyl ether, methyl-tert-butyl ether, methyl-tert amyl ether, glycol dimethyl ether and diglycol dimethyl ether, tetrahydrofuran, and dioxane; ketones such as acetone methyl ethyl ketone, methyl isopropyl ketone or methyl isobutyl ketone, esters, such as methyl acetate or ethyl acetate, nitriles, such as for example acetonitrile or propionitrile, amides such as for example, dimethylformamide, dimethylacetamide and N-methylpyrrolidone, and also dimethylsulfoxide, tetramethylene sulphone or hexamethyl phosphoric triamide. Most preferably the diluent is ethyl acetate.
[0079] The method of synthesis shown in FIG. 1 , scheme 1, step A, according to embodiments of the invention is carried out using various reagents. Suitable reagents in the reaction are alkali halides such as for example sodium bromide, sodium chloride and sodium iodide, metal acetates, such as lithium, sodium or potassium acetate, preferably sodium acetate, and alkali metal hypochlorites, preferably sodium hypochlorite.
[0080] The method of synthesis shown in FIG. 1 , scheme 1, step A, according to embodiments of the invention is carried out preferably using a catalyst, preferably cyclic nitrosyl tertiary amines, most preferably 2,2,6,6-Tetramethylpiperidinyloxy.
[0081] The reaction temperatures in method of synthesis of FIG. 1 , scheme 1, step A, according to embodiments of the invention can be varied within a wide range. In general the step can be carried out between 0 and 35° C., preferably between 5 and 10° C.
[0082] The method of synthesis shown in FIG. 1 , scheme 1, step A, according to embodiments of the invention is generally carried out under atmospheric pressure or slight positive pressure. However it is also contemplated that it is possible to operate under elevated or reduced pressures.
[0083] For carrying out the method of synthesis in FIG. 1 , scheme 1, step A, according to embodiments of the invention, the reagents are generally in approximately equimolar amounts with the starting material. However, it is possible to have one or two of the reagents in either a small excess or shortage. The catalysts are generally in lower molar amounts as is necessary for the reaction. The work up is carried out by customary methods known in the art (cf. Example 1).
Scheme 1: Step B
[0084] In the method of synthesis shown in FIG. 1 , scheme 1, according to embodiments of the invention, the compound of formula (2) is reacted to form compound of formula (3), preferably using an alkylation reaction, most preferably an O-alkyl-C-alkoxy addition reaction, particularly preferably an acetalization reaction. The compound of formula (2) is preferably a halo substituted alkanal, most preferably 10-chlorodecan-1-al and the compound of formula (3) is preferably a halo substituted dialkoxy substituted alkyl, most preferably 10-chloro-1,1-diethoxydecane.
[0085] The method of synthesis shown in FIG. 1 , scheme 1, step B, according to embodiments of the invention is carried out using various diluents. Suitable diluents are virtually all inert organic solvents. These preferably include aliphatic, aromatic, and optionally halogenated hydrocarbons such as pentane, hexane, heptane, cyclohexane, petroleum ether, benzene, ligroin, benzene, toluene, xylene, methylene chloride, ethylene chloride, chloroform, carbon tetrachloride, chlorobenzene, and o-dichlorobenzene, ethers, such as diethyl ether, dibutyl ether, methyl-tert-butyl ether, methyl-tert amyl ether, glycol dimethyl ether and diglycol dimethyl ether, tetrahydrofuran, and dioxane; ketones such as acetone, methyl ethyl ketone, methyl isopropyl ketone or methyl isobutyl ketone, esters, such as methyl acetate or ethyl acetate, nitriles, such as for example acetonitrile or propionitrile, amides such as for example, dimethylformamide, dimethylacetamide and N-methylpyrrolidone, and also dimethylsulfoxide, tetramethylene sulphone or hexamethyl phosphoric triamide. Preferably the diluent of ethyl acetate.
[0086] The method of synthesis shown in FIG. 1 , scheme 1, step B, according to embodiments of the invention is carried out using various reagents. Suitable reagents in the reaction are acetals such as chloroacetaldehyde dimethyl acetal, acetaldehyde dimethyl acetal, trimethyl orthoformate, trialkyl orthofromates most preferably triethylorthoformate, and alcohols such as methanol, ethanol, or isopropanol.
[0087] The method of synthesis shown in FIG. 1 , scheme 1, step B, according to embodiments of the invention is carried out preferably using an acid catalyst, preferably organic acid, such as methanesulfonic acid or p-toluenesulfonic acid and most preferably p-toluenesufonic acid.
[0088] The reaction temperatures in method of synthesis FIG. 1 , scheme 1, step B, according to embodiments of the invention can be varied within a wide range. In general the step can be carried out between 0 and 60° C., preferably between 15 and 25° C., most preferably at ambient temperature.
[0089] The method of synthesis shown in FIG. 1 , scheme 1, step B, according to embodiments of the invention is generally carried out under atmospheric pressure or slight positive pressure. However it is also contemplated that it is possible to operate under elevated or reduced pressures.
[0090] For carrying out the method of synthesis in FIG. 1 , scheme 1—step B according to embodiments of the invention, the reagents are generally in approximately equimolar amounts with the starting material. However, it is possible to have the reagents in either a small excess or shortage. The catalysts are generally in lower molar amounts as is necessary for the reaction. The work up is carried out by customary methods known in the art (cf. Example 1). Scheme 1: Pathway I, Step C
[0091] In the method of synthesis shown in FIG. 1 , scheme 1, pathway I, step C, according to embodiments of the invention, the compound of formula (3) is reacted to form compound of formula (4), preferably using an alkylation reaction, more preferably an alkynyl-de-halogenation reaction. The embodiments of pathway I are also referred to as Scheme 1a. The compound of formula (3) is preferably a halo substituted dialkoxy substituted alkyl, most preferably 10-chloro-1,1-diethoxydecane and the compound of formula (4) is preferably a dialkoxy substituted alkynyl, most preferably 12,12-diethoxydodec-1-yne.
[0092] The method of synthesis shown in FIG. 1 , scheme 1, pathway I, step C, according to embodiments of the invention is carried out using various diluents. Suitable diluents are virtually all inert organic solvents. These preferably include aliphatic, aromatic, and optionally halogenated hydrocarbons such as pentane, hexane, heptane, cyclohexane, petroleum ether, benzene, ligroin, benzene, toluene, xylene, methylene chloride, ethylene chloride, chloroform, carbon tetrachloride, chlorobenzene, and o-dichlorobenzene, ethers, such as diethyl ether, dibutyl ether, methyl-tert-butyl ether, methyl-tert amyl ether, glycol dimethyl ether and diglycol dimethyl ether, tetrahydrofuran, and dioxane; ketones such as acetone, methyl ethyl ketone, methyl isopropyl ketone or methyl isobutyl ketone, esters, such as methyl acetate or ethyl acetate, nitriles, such as for example acetonitrile or propionitrile, amides such as for example, dimethylformamide, dimethylacetamide and N-methylpyrrolidone, and also dimethylsulfoxide, tetramethylene sulfone or hexamethyl phosphoric triamide. Most preferably using diluent of dimethylsulfoxide.
[0093] The method of synthesis shown in FIG. 1 , scheme 1, pathway I, step C, according to embodiments of the invention is carried out using various reagents. Suitable reagents in the reaction are organometallic acetylide complexes, preferably lithium acetylide, sodium acetylide and potassium acetylide complexes, most preferably lithium acetylide, ethylenediamine complex.
[0094] The method of synthesis shown in FIG. 1 , scheme 1, pathway I, step C, according to embodiments of the invention is carried out preferably using a catalyst, most preferably a metal halide, particularly preferably sodium iodide.
[0095] The reaction temperatures in method of synthesis FIG. 1 , scheme 1, pathway I, step C, according to embodiments of the invention can be varied within a wide range. In general the step can be carried out between 10 and 60° C., preferably between 20 and 40° C., most preferably at 30° C.
[0096] The method of synthesis shown in FIG. 1 , scheme 1, pathway I, step C, according to embodiments of the invention is generally carried out under atmospheric pressure or slight positive pressure. However it is also contemplated that it is possible to operate under elevated or reduced pressures.
[0097] The yield from the method of synthesis FIG. 1 , scheme 1, pathway I, step C, according to embodiments of the invention can be varied within a wide range. Preferably the range would be greater than 50%, most preferably the range would be greater than 76%, and particularly preferably the range would be greater than 90% and very particular preferably, greater than 93%.
[0098] For carrying out the method of synthesis in FIG. 1 , scheme 1, pathway I, step C, according to embodiments of the invention, the reagents are generally in approximately equimolar amounts with the starting material. However, it is possible to have the reagents in either a small excess or shortage. The catalysts are generally in lower molar amounts as is necessary for the reaction. The work up is carried out by customary methods known in the art (cf. Example 1).
Scheme 1: Pathway I, Step D
[0099] In the method of synthesis shown in FIG. 1 , scheme 1 according to embodiments of the invention, the compound of formula (5a) is reacted to form compound of formula (5b), preferably using a substitution reaction most preferably a halogenation. The compound of formula 5(a) is preferably an alkynyl, most preferably but-1-yne and compound of formula 5(b) is preferably a halo substituted alkynyl, most preferably 1-bromobut-1-yne.
[0100] The method of synthesis shown in FIG. 1 , scheme 1, pathway I, step D, according to embodiments of the invention is carried out using various diluents. Suitable diluents are virtually all inert organic solvents. These preferably include aliphatic, aromatic, and optionally halogenated hydrocarbons such as pentane, hexane, heptane, cyclohexane, petroleum ether, benzene, ligroin, benzene, toluene, xylene, methylene chloride, ethylene chloride, chloroform, carbon tetrachloride, chlorobenzene, and o-dichlorobenzene, ethers, such as diethyl ether, dibutyl ether, methyl-tert-butyl ether, methyl-tert amyl ether, glycol dimethyl ether and diglycol dimethyl ether, tetrahydrofuran, and dioxane; ketones such as acetone, methyl ethyl ketone, methyl isopropyl ketone or methyl isobutyl ketone, esters, such as methyl acetate or ethyl acetate, nitriles, such as for example acetonitrile or propionitrile, amides such as for example, dimethylformamide, dimethylacetamide and N-methylpyrrolidone, and also dimethylsulfoxide, tetramethylene sulfone or hexamethyl phosphoric triamide. Preferably the diluent is water.
[0101] The method of synthesis shown in FIG. 1 , scheme 1, pathway I, step D according to embodiments of the invention is carried out using various reagents. Suitable reagents in the reaction are alkali metal hydroxides, such as lithium hydroxide, sodium hydroxide, and potassium hydroxide, most preferably potassium hydroxide; and halogens such as chlorine, iodine, and bromine, preferably bromine or chlorine, most preferably bromine.
[0102] The reaction temperatures in method of synthesis FIG. 1 , scheme 1, pathway I, step D, according to embodiments of the invention can be varied within a wide range. In general the step can be carried out between 10 and 85° C., preferably between 15 and 25° C., most preferably at ambient temperature.
[0103] The method of synthesis shown in FIG. 1 , scheme 1, pathway I, step D, according to embodiments of the invention is generally carried out under atmospheric pressure or slight positive pressure. However it is also contemplated that it is possible to operate under elevated or reduced pressures.
[0104] For carrying out the method of synthesis in FIG. 1 , scheme 1, pathway I, step D, according to embodiments of the invention, the reagents are generally in approximately equimolar amounts with the starting material. However, it is possible to have the halogen containing reagents in either a small excess or shortage and the metal hydroxide in great excess. The work up is carried out by customary methods known in the art (cf. Example 1).
Scheme 1: Pathway I Step E
[0105] In the method of synthesis shown in FIG. 1 , scheme 1, pathway I, step E, according to embodiments of the invention, the compound of formula (5b) is reacted with the compound of formula (4) to form compound of formula (6), preferably using a cycle of oxidative additions and reductive eliminations, most preferably a Cadiot-Chodkiewicz reaction. The compound of formula (5b) is preferably a halo substituted alkynyl, most preferably 1-bromobut-1-yne and the compound of formula (4) is preferably a dialkoxy substituted alkynyl, most preferably 12,12-diethoxydodec-1-yne. The compound of formula (6) is preferably a dialkoxy substituted diynyl and most preferably 16,16-diethoxyhexadeca-3,5-diyne.
[0106] The method of synthesis shown in FIG. 1 , scheme 1, pathway I, step E, according to embodiments of the invention is carried out using various diluents. Suitable diluents are virtually all inert organic solvents. These preferably include aliphatic, aromatic, and optionally halogenated hydrocarbons such as pentane, hexane, heptane, cyclohexane, petroleum ether, benzene, ligroin, benzene, toluene, xylene, methylene chloride, ethylene chloride, chloroform, carbon tetrachloride, chlorobenzene, and o-dichlorobenzene, ethers, such as diethyl ether, dibutyl ether, methyl-tert-butyl ether, methyl-tert amyl ether, glycol dimethyl ether and diglycol dimethyl ether, tetrahydrofuran, and dioxane; ketones such as acetone, methyl ethyl ketone, methyl isopropyl ketone or methyl isobutyl ketone, esters, such as methyl acetate or ethyl acetate, nitriles, such as for example acetonitrile or propionitrile, amides such as for example, dimethylformamide, dimethylacetamide and N-methylpyrrolidone, and also dimethylsulfoxide, tetramethylene sulfone or hexamethyl phosphoric triamide, alcohols such as methanol, ethanol, n-propanol, isopropanol, butanol, tert-butanol. Preferably the diluents of methanol and methyl-tert-butyl ether.
[0107] The method of synthesis shown in FIG. 1 , scheme 1, pathway I, step E, according to embodiments of the invention is carried out using various reagents. Suitable reagents in the reaction are monoamines (primary or alkyl hydroxylamines), such as N-methyl or N-ethyl hydroxylamine most preferably hydroxylamine hydrochloride, and basic alkyl amines, such as ethylamine, triethylamine, propylamine, preferably n-propylamine.
[0108] The method of synthesis shown in FIG. 1 , scheme 1, pathway I, step E, according to embodiments of the invention is carried out preferably using a catalyst, most preferably a metal halide, particularly preferably copper (I) chloride.
[0109] The reaction temperatures in method of synthesis FIG. 1 , scheme 1, pathway I, step E, according to embodiments of the invention can be varied within a wide range. In general the step can be carried out between −40° C. and 25° C., preferably between 0 and −20° C., most preferably about 0° C. and about −20° C.
[0110] The method of synthesis shown in FIG. 1 , scheme 1, pathway I, step E according to embodiments of the invention is generally carried out under atmospheric pressure or slight positive pressure. However it is also contemplated that it is possible to operate under elevated or reduced pressures.
[0111] For carrying out the method of synthesis in FIG. 1 , scheme 1, pathway I - step E according to embodiments of the invention, the reagents are generally in excess in molar amounts with the starting material. The catalysts are generally in lower molar amounts as is necessary for the reaction. The work up is carried out by customary methods known in the art (cf. Example 1).
[0112] The yield from the method of synthesis FIG. 1 , scheme 1, pathway I, step E according to embodiments of the invention can be varied within a wide range. Preferably the range would be greater than 50%, most preferably the range would be greater than about 76%, and particularly preferably the range would be greater than 87%.
Scheme 1: Pathway II Step G
[0113] In the method of synthesis shown in FIG. 1 , scheme 1, pathway II, step G, is an optional step according to embodiments of the invention based on commercial availability of compound of formula (8b), needs of the synthesis and the like. The embodiments of pathway II are also referred to as Scheme 1b. The compound of formula (8a) is reacted to form compound of formula (8b), preferably using a triple bond migration rearrangement reaction, most preferably an isomerization. The compound of formula (8a) is preferably an internal alkyne, most preferably 2,4-hexadiyne and the compound of formula (8b) is preferably a terminal alkyne, most preferably, 1,3-hexadiyne.
[0114] The method of synthesis shown in FIG. 1 , scheme 1, pathway II, step G, according to embodiments of the invention is carried out using various diluents. Suitable diluents are virtually all inert organic solvents. These preferably include aliphatic, aromatic, and optionally halogenated hydrocarbons such as pentane, hexane, heptane, cyclohexane, petroleum ether, benzene, ligroin, benzene, toluene, xylene, methylene chloride, ethylene chloride, chloroform, carbon tetrachloride, chlorobenzene, and o-dichlorobenzene, ethers, such as diethyl ether, dibutyl ether, methyl-tert-butyl ether, methyl-tert amyl ether, glycol dimethyl ether and diglycol dimethyl ether, tetrahydrofuran, and dioxane; ketones such as acetone, methyl ethyl ketone, methyl isopropyl ketone or methyl isobutyl ketone, esters, such as methyl acetate or ethyl acetate, nitriles, such as for example acetonitrile or propionitrile, amides such as for example, dimethylformamide, dimethylacetamide and N-methylpyrrolidone, and also dimethylsulfoxide, tetramethylene sulfone or hexamethyl phosphoric triamide. Most preferably using diluent of ether.
[0115] The method of synthesis shown in FIG. 1 , scheme 1, pathway II, step G, according to embodiments of the invention is carried out using various reagents. Suitable reagents in the reaction are bases, such as strong bases of alkali metal amides sodium amide and potassium 3-aminoproylamide, preferably sodium amide.
[0116] The reaction temperatures in method of synthesis FIG. 1 , scheme 1, pathway II, step G according to embodiments of the invention can be varied within a wide range. In general the step can be carried out between -10 and 50° C., preferably between 0 and 20° C., most preferably at 10° C.
[0117] The method of synthesis shown in FIG. 1 , scheme 1, pathway II-step G according to embodiments of the invention is generally carried out under atmospheric pressure or slight positive pressure. However it is also contemplated that it is possible to operate under elevated or reduced pressures.
[0118] The yield from the method of synthesis FIG. 1 , scheme 1, pathway II, step G according to embodiments of the invention can be varied within a wide range. Preferably the range would be greater than 50%, most preferably the range would be greater than 76%, and particularly preferably the range would be greater than 90%.
[0119] For carrying out the method of synthesis in FIG. 1 , scheme 1, pathway II, step G, according to embodiments of the invention, the reagents are generally in approximately equimolar amounts with the starting material. However, it is possible to have the reagents in either a small excess or shortage. The work up is carried out by customary methods known in the art (see C. A. Brown and A. Yamashita (1975). “Saline hydrides and superbases in organic reactions. IX. Acetylene zipper. Exceptionally facile contrathermodynamic multipositional isomerization of alkynes with potassium 3-aminopropylamide”. J. Am. Chem. Soc. 97 (4): 891-892).
Scheme 1: Pathway II Step H
[0120] In the method of synthesis shown in FIG. 1 , scheme 1, pathway II, Step H, according to embodiments of the invention, the compound of formula (3) is reacted with compound of formula (8b) to form compound of formula (6), preferably using a nucleophilic addition reaction. The reaction is optionally performed in situ with the reactions of step G. The compound of formula (3) is preferably a halo substituted dialkoxy substituted alkyl, most preferably 10-chloro-1,1-diethoxydecane, the compound of formula (8b) is preferably a terminal alkynyl, most preferably, 1,3-hexadiyne, the compound of formula (6) is preferably a dialkoxy substituted diynyl and most preferably 16,16-diethoxyhexadeca-3,5-diyne.
[0121] The method of synthesis shown in FIG. 1 , scheme 1, pathway II, step H, according to embodiments of the invention is carried out using various diluents. Suitable diluents are virtually all inert organic solvents. These preferably include aliphatic, aromatic, and optionally halogenated hydrocarbons such as pentane, hexane, heptane, cyclohexane, petroleum ether, benzene, ligroin, benzene, toluene, xylene, methylene chloride, ethylene chloride, chloroform, carbon tetrachloride, chlorobenzene, and o-dichlorobenzene, ethers, such as diethyl ether, dibutyl ether, methyl-tert-butyl ether, methyl-tert amyl ether, glycol dimethyl ether and diglycol dimethyl ether, tetrahydrofuran, and dioxane; ketones such as acetone, methyl ethyl ketone, methyl isopropyl ketone or methyl isobutyl ketone, esters, such as methyl acetate or ethyl acetate, nitriles, such as for example acetonitrile or propionitrile, amides such as for example, dimethylformamide, dimethylacetamide and N-methylpyrrolidone, and also dimethylsulfoxide, tetramethylene sulfone or hexamethyl phosphoric triamide. Preferably using diluent of ammonia, most preferably using a diluent of ether.
[0122] The method of synthesis shown in FIG. 1 , scheme 1, pathway II, step H, according to embodiments of the invention is carried out using various reagents. Suitable reagents in the reaction are bases, such as strong bases of alkali metal amides, sodium amide, lithium amide, potassium amide, magnesium amide, and potassium 3-aminoproylamide, preferably sodium amide.
[0123] The reaction temperatures in method of synthesis FIG. 1 , scheme 1, pathway II, step H, according to embodiments of the invention can be varied within a wide range. In general the step can be carried out between -10 and 50° C. , preferably between 0 and 20° C., most preferably at 10° C.
[0124] The method of synthesis shown in FIG. 1 , scheme 1, pathway II, step H, according to embodiments of the invention is generally carried out under atmospheric pressure or slight positive pressure. However it is also contemplated that it is possible to operate under elevated or reduced pressures.
[0125] The yield from the method of synthesis FIG. 1 , scheme 1, pathway II, step H, according to embodiments of the invention can be varied within a wide range. Preferably the range would be greater than 50%, most preferably the range would be greater than 76%, and particularly preferably the range would be greater than 85%.
[0126] For carrying out the method of synthesis in FIG. 1 , scheme 1, pathway II, step H, according to embodiments of the invention, the reagents are generally in approximately equimolar amounts with the starting material. However, it is possible to have the reagents in either a small excess or shortage. The work up is carried out by customary methods known in the art.
Scheme 1: Step F
[0127] In the method of synthesis shown in FIG. 1 , scheme 1 according to embodiments of the invention, the compound of formula (6) is reacted to form the compound (7), preferably using a reduction reaction and a hydrolysis reaction, more preferably an alkyne reduction and an acetal hydrolysis. The compound of formula (6) is preferably a dialkoxy substituted diynyl, most preferably 16,16-diethoxyhexadeca-3,5-diyne and the compound of formula (7) is preferably a navel orangeworm sex attractant pheromone, most preferably the cis-cis isomer of the pheromone, and particularly preferably is (Z,Z)-11,13-hexadecadien-1-al.
[0128] The method of synthesis shown in FIG. 1 , scheme 1, step F, according to embodiments of the invention is carried out using various diluents. Suitable diluents are virtually all inert organic solvents. These preferably include aliphatic, aromatic, and optionally halogenated hydrocarbons such as pentane, hexane, heptane, cyclohexane, petroleum ether, benzene, ligroin, benzene, toluene, xylene, methylene chloride, ethylene chloride, chloroform, carbon tetrachloride, chlorobenzene, and o-dichlorobenzene, ethers, such as diethyl ether, dibutyl ether, methyl-tert-butyl ether, methyl-tert amyl ether, glycol dimethyl ether and diglycol dimethyl ether, tetrahydrofuran, and dioxane; ketones such as acetone, methyl ethyl ketone, methyl isopropyl ketone or methyl isobutyl ketone, esters, such as methyl acetate or ethyl acetate, nitriles, such as for example acetonitrile or propionitrile, amides such as for example, dimethylformamide, dimethylacetamide and N-methylpyrrolidone, and also dimethylsulfoxide, tetramethylene sulfone or hexamethyl phosphoric triamide, Preferably the diluent is tetrahydrofuran.
[0129] The method of synthesis shown in FIG. 1 , scheme 1, step F, according to embodiments of the invention is carried out using various reagents. Suitable reagents in the reaction are alkenes such as 2-methyl propene, 2-butene, 2-methyl butene and cycloalkenyls, such as cyclopentene, cyclohexene, cycloheptene and cyclooctene, most preferably cyclohexene; organometallic complexes, such as borane complexes, including borane-THF, borane-methylsulfide and borane-amine complexes, preferably borane-N,N-diethylaniline;, a weak acid, such as formic acid, trifluoroacetic acid and acetic acid preferably glacial acetic acid; and either a strong aqueous acid, such as HCl or sulfuric acid, preferably sulfuric acid, or a metal tetrafluoroborate complex, such as copper (II) tetrafluoroborate or sodium borofluoride.
[0130] An unexpected benefit in using the preferred embodiment with borane-N,N-diethylaniline is the storage stability of the reagent, lack of nuisance odor and efficient reactions. While borane-THF is unstable with respect to storage past several months at ambient temperatures, DEANB is stable for long periods at ambient temperature. DEANB does not have a nuisance odor such as the case in using borane methyl sulfide. DEANB provides high yields of stereospecific product that is comparable or better than alternatives such as borane THF. DEANB as normally commercially available comes in a higher molar strength (5.6 M) than alternative boranes such as borane THF (1M) which allows more efficiency of utilizing higher concentrations in the reaction solution. Another efficiency is the reactivity of DEANB. This allows an almost stochiometric amount of reagent (2:1) to be used to form the dicyclohexyl borane as compared to the borane THF which requires an excess.
[0131] According to embodiments of the invention in FIG. 1 , scheme 1, step F, efficiencies are gained in the use of an organo metallic reducing agent in conjunction with hydrolysis agents such as a strong aqueous acid or metal fluoroborate complexes allowing for a combination of transformations in the compound with both a reduction in diynyls and hydrolysis of the acetal. Furthermore, use of the metal fluoroborate complexes allows for higher yields in the final transformation step.
[0132] The reaction temperatures in method of synthesis FIG. 1 , scheme 1-step F according to embodiments of the invention can be varied within a wide range. In general the step can be carried out between −10° C. and 80° C. , preferably between 5 and 60° C., most preferably about 5° C. and about 60° C.
[0133] The method of synthesis shown in FIG. 1 , scheme 1- step F according to embodiments of the invention is generally carried out under atmospheric pressure or slight positive pressure. However it is also contemplated that it is possible to operate under elevated or reduced pressures.
[0134] For carrying out the method of synthesis in FIG. 1 , scheme 1, step F, according to embodiments of the invention, the reagents are generally in excess in molar amounts with the starting material. The work up is carried out by customary methods known in the art (cf. Example 1). In the general work-up, the final product's separation or isolation from other synthetic constituents also known as purification can be carried out implementing common techniques such as concentration on silica gel, normal phase LC, reverse-phase HPLC, distillation or crystallization. A crystallization technique used for isolation may use a salt adducts such as sodium bisulfite. The purified final product can be held as a salt adduct to create a more stabile product. The salt adduct can subsequently be removed by application of a base. Crystallization can be advantageous because it does not apply heat, as in distillation, allowing for less degradation with thermally sensitive products.
[0135] The yield from the method of synthesis FIG. 1 , scheme 1, step F, according to embodiments can be varied within a wide range. Preferably the range would be greater than 50%, most preferably the range would be greater than about 76%, and particularly preferably the range would be greater than 87%.
[0136] The method of synthesis according to embodiments of the inventions allows the final product to be used in the methods of trapping insects, methods for attracting insect pests, methods of disrupting mating as described in U.S. patent application 2006/0280765, and to be admixed with other pheromones from the Ando type I and type II categories for the same.
[0137] The method of synthesis according to embodiments of the invention allows for a synthesis kit which may include all necessary reagents as described herein, diluents as described herein, all intermediate and starting materials as described herein, and any necessary apparatuses to perform the reaction steps as described herein.
[0138] The following example of a specific embodiment for carrying out the invention is offered for illustrative purposes only and is not intended to limit the scope of the present invention in any way.
Procedures for the Examples
[0139] The structures and purities of the compounds of the following Examples were confirmed by proton magnetic resonance spectroscopy ( 1 H NMR) and gas chromatography (GC).
[0140] Proton magnetic resonance ( 1 H NMR) spectra were determined using a 300 megahertz, Varian Mercury System spectrometer operating at a field strength of 300 megahertz (MHz). Chemical shifts are reported in parts per million (ppm) downfield from an internal tetramethylsilane standard. Alternatively, 1 H NMR spectra were referenced to residual protic solvent signal: CHCl 3= 7.26 ppm. Peak multiplicities are designated as follows: s=singlet; d=doublet; dd=doublet of doublets; t=triplet; q=quartet, qn=quintet; br=broad resonance; and m=multiplet. Coupling constants are given in Hertz. GC chromatographs were run on a 5890 Series II Hewlett Packard System fitted with a SP™-2380 30 m×0.52 mm x 0.20 μm column (SP) or HP-Ultra 2, 25 m×0.20 mm×0.33 μm column (HP). Unless otherwise stated, a gradient of 10° C./min starting at 40° C. held for 2 minutes moving the gradient for 25 minutes and bringing the temperature up to 250° C. for 2.0 minutes. Water content was estimated utilizing a Karl Fisher (KF) apparatus. Retention times (Rt) are given in minutes. All reactions were performed in septum-sealed flasks under a slight positive pressure of nitrogen, unless otherwise noted. All commercial reagents were used as received from their respective suppliers (Su). The following abbreviations are used herein: DEANB (borane-N,N-diethylaniline complex); NaBr (sodium bromide); NaOAc (sodium acetate) NaOCl (sodium hypochlorite); NaHCO 3 (sodium bicarbonate); NaHSO 3 (sodium bisulfite); NaI (sodium iodide); KOH (potassium hydroxide); Br 2 (bromine); N 2 (nitrogen); MTBE (methyl-tert-butyl ether), HONH 2 .HCl (hydroxylamine hydrochloride), CuCl (copper (I) chloride); H 2 SO 4 (sulfuric acid), DMSO (dimethylsulfoxide); MeOH (methanol); THF (tetrahydrofuran); EtOAc (ethyl acetate); min. or min (minutes); h (hours).
EXAMPLE 1
[0141] See FIG. 7 for the general synthetic scheme for Example 1.
EXAMPLE 1
STEP A
[0142]
[0143] To a solution of 10-chlorodecanol 1 (20.0 g, 103.77 mMol, Su: Laviana (Lot: T-1094001), NaBr (8.33 g, 80.94 mMol, PA reagent, Su: Acros), NaOAc.3H 2 O (21.18 g, 155.66 mMol, ACS reagent, Su: Aldrich) and 2,2,6,6-tetramethylpiperidinooxy (TEMPO) (162 mg, 1.04 mMol-(98% pure) Su: Acros) in H 2 O (40 ml, tap) and EtOAc (120 ml, ACS reagent, Pharmco/AAPER) was added drop-wise NaOCl (100 ml, 115.19 mMol, 7.11% w/v solution Su: Aldrich) while maintaining internal temperature below 10° C. and mechanical stirring. Concentration of NaOCl was determined by titration. The reaction progress was monitored by GC and considered complete when <3A% of the starting alcohol 1 was remaining. After 2 hr stirring at 5° C., water (60 ml, H 2 O tap) was charged into the reaction mixture to quench the reaction, and aqueous NaHSO 3 (˜1.0 ml, 2.0 M) was used to destroy remaining NaOCl if necessary. Check for remaining NaOCl with KI-starch test paper (Su: Fisher Scientific). Aqueous phase was extracted with EtOAc (50 ml) after phase separation. The combined organic layers were washed with H 2 O (120 ml). The resulting organic phase was concentrated under reduced pressure (pot temperature ˜35° C.) to a volume of ˜50 ml. Fresh EtOAc (100 ml) was charged into it and then concentrated under reduced pressure (pot temperature ˜35° C.) to the final volume of 50 ml. The water content of this resultant solution was checked by Karl Fisher method (repeat if necessary KF <0.4%), and the light-yellow solution was used without further purification. GC: column SP, starting condition 50° C. (1.0 min) then ramp to 250° C. at a rate of 10° C./min and hold at 250° C. for 1 minute, Rt=11.8 min for 10-chlorodecanol 1 and Rt=10.3 min for 10-chlorodecanal 2. 1 H NMR (CDCl 3 , 300 MHz): δ 9.77 (t, J=1.7 Hz, 1H), 3.53 (t, J=6.7 Hz, 2H), 2.43 (dt, J=7.5 Hz, J=1.7 Hz, 2H), 1.77 (qn, J=7.5 Hz, 2 Hz), 1.63 (m, J=7.2 Hz, 2H), 1.42 (m, J=7.2 Hz, 2H), 1.30 (br s, 8H).
EXAMPLE 1
STEP B
[0144]
[0145] To the solution of 10-chlorodecanal 2 in EtOAc (50 ml, 103.77 mMol Su: from step A) at ambient temperature, under blanket of N 2 , was charged p-toluenesulfonic acid monohydrate (200 mg, 1.04 mMol, (99%) Su: Acros) and triethylorthoformate (19 ml, 114.15 mMol (98%) Su:Acros). The reaction was monitored by GC for compound 2 consumption (compound 2 <2.0 area % by GC). After 3 hr stirring at ambient temperature, a solution of H 2 O (50 ml) and saturated NaHCO 3 (aq.) (50 ml) was poured into the reaction mixture to quench the reaction. The aqueous layer was extracted with EtOAc (50 ml) after phase separation. The combined organic phases were washed with a solution of H 2 O (50 ml) and brine (50 ml). The resulting organic phase was concentrated under reduced pressure (pot temperature ˜35° C.) to a volume of 50 ml. Fresh EtOAc (100 ml) was charged into it and then concentrated under reduced pressure (pot temperature ˜35° C.) to the final volume of 50 ml. The water content was checked by Karl Fisher method (repeat if necessary KF <0.4%). The resultant solution was concentrated under reduced pressure (pot temperature ˜35° C.) until a constant weight (˜28 g) was established. Resultant light yellow oil was used without further purification. GC: column SP, starting condition 50° C. (1.0 min) then ramp to 250° C. at a rate of 10° C./min and hold at 250° C. for 1 minute, Rt: 10.3 min for 10-chlorodecanal 2 and 9.9 min for 10-chloro-1,1-diethoxydecane 3. 1 H NMR (CDCl 3 , 300 MHz): δ 4.48 (t, J=5.93, 1H), 3.6 (m, J=7.03 Hz, 2H), 3.53 (t, J=6.8 Hz, 2H), 3.5 (q, J=7.03 Hz, 2), 1.76 (qn, J=6.85 Hz, 2H), 1.6 (m, J=6.85 Hz, 2H), 1.4 (m, J=6.85 Hz, 2H), 1.29 (br s, 10H), 1.20 (t, J=7.03 Hz, 6H);
EXAMPLE 1
STEP C
[0146]
[0147] To a dark solution of lithium acetylide, ethylenediamine complex (13.8 g, 134.90 mMol, (90%) Su: Aldrich) and NaI (0.78 g, 5.19 mMol, (99+%), Su: Acros) in DMSO (100 ml anhydrous (99.7%) Su: Acros) was charged 10-chloro-1,1-diethoxydecane 3 (27.48 g, 103.77 mMol Su: from step B) while maintaining reaction temperature around 30° C., under a blanket of N 2 . The addition funnel was rinsed with DMSO (15 ml, anhyrdrous, Su: Acros). The solution was monitored by GC for compound 3 consumption (compound 3 <2.0 Area % by GC). After 4 hr stirring at 30° C., H 2 O (200 ml) were charged into the reaction mixture to quench the reaction. The aqueous layer was extracted with heptane (2×200 ml). The organic layer was filtered through a plug of Celite® 521 (15 g, Su: Sigma-Aldrich) one by one after phase separation. The combined filtrate was washed with a solution of H 2 O (100 ml) and brine (50 ml). The water in this organic solution was removed by azeotropic distillation under normal conditions by means of adding and removing heptane (repeat if necessary until KF=˜0.2%). The resultant solution was concentrated under reduced pressure (pot temperature ˜35° C.) to give 24.6 g of 12,12-diethoxydodec-1-yne 4 as an amber liquid (93% yield over steps A thru C, after C). This material was used without further purification. GC: column SP, Rt: 12.2 for 10-chloro-1,1-diethoxydecane 3, and Rt: 11.1 min for 12,12-diethoxydodec-1-yne 4 (<5 Area %). 1 H NMR (CDCl 3 , 400 MHz): δ 4.48 (t, J=5.60, 1H), 3.6 (m, J=7.07 Hz, 2H), 3.5 (m, J=7.07 Hz, 2H), 2.18 (dt, J=7.10, 2.80 Hz, 2H), 1.94 (t, J=2.60 Hz, 1H), 1.6 (m, 2H), 1.52 (qn, J=7.2 Hz, 2H), 1.4 (m, 2H), 1.29 (br s, 10H), 1.20 (t, J=7.00 Hz, 6H).
EXAMPLE 1
STEP D
[0148]
[0149] To a solution of KOH (88.0 g, 1.57 Mole, flakes, 90+%, Su: Aldrich) in H 2 O (400 ml, tap) was charged Br 2 (17.5 ml, 340 mMole, reagent grade, Su: Aldrich) at ambient temperature. Through this potassium bromide/bromate solution in Dreschel bottle (washing bottle) with fritted tube for gas dispersal was bubbled 1-butyne 5a (5.4 g, 99.83 mMol, 98+%, Su: Aldrich) at ambient temperature until the light yellow color of this aqueous solution turned colorless. The resultant aqueous solution was extracted with MTBE (200 ml, ACS reagent, Su: Pharmco/AAPER). After the separation of aqueous and organic layer, the organic solvents (˜175 ml) were removed by normal distillation (temperature of distillate head: up to 60° C. and pot temperature: ˜85° C.) to give a light yellow solution of 1-bromobutyne 5b in MTBE. GC: column HP, isocratic 35° C. (10min), Rt: 4.92 min, 1 H NMR (CDCl 3 , 300 MHz): δ 2.22 (q, J=7.50, 2H), 1.15 (t, J=7.50 Hz, 3H);
EXAMPLE 1
STEP E
[0150]
[0151] To a suspension of hydroxylamine hydrochloride (7.6 g, 117.8 mMol, 99%, Su: Aldrich) and copper (I) chloride (0.39 g, 3.93 mMol, 97%, Su: Aldrich) in MeOH (80 ml, reagent ACS, Su: Pharmco/AAPER) at 0° C., under a blanket of N 2 , was charged n-propylamine (20 ml, 243.27 mMol, 98%, Su: Aldrich). After 15 min stirring, a solution of 12,12-diethoxydodec-1-yne 4 (10 g, 39.3 mMol, Su: from step C) in MeOH (10 ml) was charged and the addition funnel was rinsed with MeOH (5 ml). After 15 min stirring, the resulting clear solution was cooled down to −20° C. A solution of 1-bromobutyne 5b in MTBE (10.7 ml, 4.4 M, 47.2 mMol, Su: from step D) was added drop-wise within 3 hrs while maintaining temperature below −20° C. The reaction was monitored for the consumption of 12,12-diethoxydodec-1-yne 4 (<3.0 Area % by GC). After 2 hours, the resulting reaction mixture was directly extracted with heptane (3×200 ml). The extracted heptane-layer was passed through a pad of silica gel (10 g, gravity grade, Su: Silicycle). Solvent removed under reduced pressure to concentrate diyne 6 (10.5 g, 87% yield, 97.8 Area % by GC). This material was used without further purification. GC: column SP, Rt: 11.1 for 12,12-diethoxydodec-1-yne 4 (<3 Area %) and Rt: 16.8 for 16,16-diethoxyhexadeca-3,5-diyne 6. 1 H NMR (CDCl 3 , 300 MHz): δ 4.48 (t, J=5.85, 1H), 3.6 (m, J=7.10 Hz, 2H), 3.5 (m, J=7.10 Hz, 2H), 2.26 (m, J=7.50 Hz, 2H), 1.6 (m, 2H), 1.5 (m, 2H), 1.4˜1.25 (br, 12H), 1.20 (t, J=7.05 Hz, 6H), t, J=7.50 Hz, 3H).
EXAMPLE 1
STEP F
[0152]
[0153] To a solution of cyclohexene (10.6 ml, 104.84 mMol, 99%, Su: J-Star Research) in THF (20 ml {+/−0.2 ml}, distilled, Su: Pharmco/AAPER) was added DEANB (9.1 ml, 51.39 mMol, Su: Aldrich) at ˜5° C. under a blanket of N 2 . After 2 hr stirring, 16,16-diethoxyhexadeca-3,5-diyne 6 (6.3 g, 20.56 mMol Su: from Step E) was charged while maintaining temperature ˜5° C. Solution was monitored ˜2.5 hrs at ˜5° C. until clear. Solution was stirred 4 hr at ambient temperature. The solution was monitored by GC for the consumption of compound 6 (compound 6 <2.0 Area % by GC). Glacial acetic acid (15.0 ml, 261 mMol, ACS grade, Su: Pharmco/AAPER) was charged. The solution was monitored after 4 hr stirring at ambient temperature until colorless. Aqueous sulfuric acid (100 ml, 4.0 M, Su: Aldrich) was charged, and the resulting solution was stirred at 60° C. for 2 hrs. After cooling to ambient temperature, the solution was extracted with heptane (2×100 ml). The combined organic layers were washed with H 2 O (100 ml) and saturated NaHCO 3 (aq) (100 ml, Su: J-Star Research), respectively. A crude product (9.5 g) was obtained after solvent removal. This crude product was re-dissolved in heptane (100 ml) and stirred with H 2 O (100 ml). After 4 hr stirring and phase separation, the organic layer was filtered through a pad of silica gel (6.3 g, gravity grade, Su: Silicycle) and concentrated to give crude compound 7 (5.4 g, 83% yield). Vacuum distillation gave compound 7 (1.55 g, 32% yield for this step) at 129˜130° C./0.65 mmHg. GC: column SP, Rt: 14.3 min for (11Z,13,Z)-11,13-hexadecadien-1-al 7, 16.8 min for 16,16-diethoxyhexadeca-3,5-diyne 6 (<3 Area %) shown in FIG. 4 . 1 H NMR (CDCl3, 300 MHz): δ 9.77 (t, J=1.95 Hz, 1H), 6.23 (m, 2H), 5.44 (m, 2H), 2.42 (dt, J=7.27, 1.80 Hz, 2H), 2.18 (m, 4H), 1.63 (m, J=7.35 Hz, 2H), 1.4˜1.25 (broad, 12H), 1.00 (t, J=7.50 Hz, 3H).
[0154] Compound 7 obtained by the above synthesis was found to be identical to a standard navel orangeworm pheromone (Z,Z)-11,13-hexadecadien-1-al CAS number 71317-73-2 by GC shown in FIG. 5 . and by ‘H NMR.
[0155] While the invention has been described in terms of various embodiments, preferred embodiments, specific embodiments, specific examples, and applications thereof, the invention should be understood as not being limited by the foregoing detailed description, but as being defined by the appended claims and their equivalents. Numerous modifications and variations could be made thereto by those skilled in the art without departing from the scope of the invention set forth in the claims. | One or more embodiments of the invention are directed to the synthetic methods for making lepidopteran pheromones including navel orangeworm pheromones. The synthetic methods involve novel, efficient, and environmentally benign steps and procedures. | 2 |
TECHNICAL FIELD
This invention relates generally to a header of an agricultural cutting machine, such as a combine, windrower or other crop harvesting machine, or a mower, and more particularly, to a guard for a sickle of a header, integrally incorporating an air discharge system including streamlined, non-obstructive air outlets operable for effectively directing pressurized air rearwardly over the sickle and toward a floor or pan of a header, for blowing cut plant material, particularly loose grain and the like, onto a floor or pan of the header, so as to avoid loss of the material, without interfering with the cutting action or plant flow over the guard.
BACKGROUND ART
Sickles typically including cutter bars supporting a row of knives, have been used to cut plants, including, but not limited to, hay, grasses, small grains and the like, for many years. The knives are composed of a plurality of knife or sickle sections which are mounted in side by side relation forming an elongate metal knife assembly. The elongate knife assembly is normally supported so as to slide longitudinally through slots in, or over, forwardly projecting, spaced apart guards. The knife assembly moves back and forth in a reciprocating movement to move the knives relative to the guards so that the leading knife edges of the knives cross over the guards or through the slots in the guards. This produces a shearing or cutting action which severs plant stems and stalks or other material which flows into and is captured in the spaces between the knives and the guards.
In operation, as the crop cutting machine moves forwardly over a field, it is desirable for the plant stems and stalks to flow smoothly and uninterruptedly into the spaces between the guards, so as to be cleanly severed by the knives. It is also desired for the cut plant material to flow smoothly and largely uninterruptedly over the sickle, not bunch up thereon, and flow or fall onto a floor or pan of the header, particularly when the cutting machine is a harvester. Often, harvesters also include a rotary reel disposed over the sickle to facilitate the induction of the plants into the sickle, clear cut plant material from the sickle, and help move the cut crops onto the header floor. On the header, the cut crop material is typically conveyed sidewardly toward the center of the header, by an auger or belt, for induction into a feeder of the machine or other apparatus.
A problem that can occur, however, when cutting crops in the above manner, is that sometimes as a result of the cutting action, crops will not be inducted into the header, but instead will be lost. For instance, as a result of a dull or worn sickle, the crop stalks or stems may be jerked, bent, and/or torn instead of cleanly cut, which can shake grain loose from the crop before it enters the header, such that some of the loose grain can fall to the ground in front of the header. The bats or tines of reel can also strike the crops and shatter pods, etc., to loosen or thresh the grain so as to be lost, particularly under dry conditions. Still further, the augers for conveying the cut crops toward the center of the header can include fingers that operate to pull the cut crops into the auger, which can unintentionally thresh some of the grain from the crop. As a result, a significant amount of loose grain can be present in the forward region of a header, on and above the sickle and guards, which is at risk of loss if not conveyed or inducted onto the header.
Numerous devices and systems have been developed over many years, in attempts to blow loose grain toward the header. Reference in this regard, the system utilizing pressurized air directed through nozzles or jets on or in connection with the sickle guards disclosed in McDonnell U.S. Pat. No. 6,085,510, issued Jul. 11, 2000. However, an observed shortcoming of the embodiment of the system of the McDonnell patent illustrated in FIGS. 1-3 of that patent, is that the air nozzles or outlets are located in the slots of the guards in which the sickle knives move. In a second embodiment shown in FIG. 4 and subsequent Figures of the McDonnell patent, nozzles project sidewardly from the guards into the spaces between the adjacent guards, so as to be located in the crop flow paths along and between the guards. Reference also, Phillips U.S. Pat. No. 2,718,744, issued Sep. 27, 1955; and Klinger U.S. Pat. No. 2,737,006, issued Feb. 26, 1954. The Phillips and Klinger patents also utilize pressurized air nozzles, but located on structures on the guards or extending forwardly therefrom (Phillips massively so), and which also extend sidewardly into the crop flow path (more so in Klinger) so as to possibly interfere with crop flow to the cutting region between the sickle knife and side of the guard. Any outward projection of a nozzle into the crop flow path can result in contact with crop plants forwardly of the front edge of the header pan that can jar the plants, to cause them to drop grain, which can fall between the guards so as to be lost. The air flow ducts of Phillips and Klinger are also significantly larger than the guards and extend beneath the guards, so as to limit the positioning options of the guards and the header relative to the ground, particularly the closeness to the ground and the ability to orient the guards toward the ground. The Phillips and Klinger air flow ducts are also exposed to damage from contact with the ground.
Thus, what is sought is an air discharge system for guards of a sickle of a header of an agricultural plant cutting machine, that is effective for discharging flows of air rearwardly, for directing loose grain and other crop elements toward the header, yet which is unobtrusive and overcomes one or more of the problems, disadvantages, and shortcomings referenced above.
SUMMARY OF THE INVENTION
What is disclosed is an integral air discharge system for guards of a sickle of a header of an agricultural plant cutting machine, such as, but not limited to, a combine, windrower, or the like, that is effective for discharging flows of air rearwardly, for directing loose grain and other crop elements toward the header, yet which is unobtrusive and overcomes one or more of the problems, disadvantages, and shortcomings referenced above.
According to a preferred aspect of the invention, a guard for a sickle of an agricultural plant cutting machine includes a base configured for mounting to a header of a plant cutting machine adjacent to a forward edge of an upwardly facing floor of the header, and an elongate finger attached to the base and oriented relative thereto so as to extend forwardly therefrom when mounted to a header. The finger includes a forward tip portion opposite the base, the finger including a slot extending sidewardly therethrough intermediate the base and the tip portion and configured for cooperatively receiving a sickle knife for reciprocating sideward movement relative to the finger. The finger includes opposite side surfaces adjacent to opposite ends of the slot and against which the sickle knife will cut plants when reciprocated sidewardly relative to the finger, and the finger including a longitudinally extending, upwardly facing surface extending from the base to the forward tip portion. The upwardly facing surface includes a rearwardly facing air discharge nozzle therein, and the finger includes an air flow passage extending internally therethrough from an air inlet adjacent the base to the nozzle for delivering a flow of pressurized air thereto, the nozzle being at least mostly flush with or recessed into the upwardly facing surface. As a result, the nozzle is operable for discharging the flow of air rearwardly over the finger without obstructing plant material flow thereover. Preferably, the pressure of the air will be sufficient to blow at least a substantial amount of loose grain and other plant material located forwardly of the front edge of the header floor, onto the header floor for collection by a conveyor of the header for processing.
According to another preferred aspect of the invention, the air inlet is disposed beside the base, and is connected to a suitable source of pressurized air, which can be, for instance, an air compressor located on the plant cutting machine, or on the header itself. According to another preferred aspect, the guard is configured in side by side spaced apart relation with one or more additional guards, so as to be conveniently jointly mountable to a header. And, a joint air inlet or separate inlets can be provided in connection with the air flow passages, as desired or required for a particular application.
According to still another preferred aspect of the invention, the nozzle is integrated into the upwardly facing surface of the finger forwardly of or above the slot containing the sickle knife, so as to be positioned just forwardly of, or over a forward region of, the cutting region of the sickle, such that the air flow discharged from the nozzle will be strongest at the location where the most loose grain is anticipated to be present. To facilitate this positioning, the air passage will preferably include a lower portion which extends forwardly under the slot, and an upper portion in connection with the lower portion and extending upwardly and possibly rearwardly to the nozzle.
Optional aspects of the invention include a shallow concave channel or recess rearwardly of the nozzle, wherein the nozzle is oriented to discharge the flow of air through the channel, thereby facilitating the desired smooth, uninterrupted flow of plant material over the nozzle, while providing a desired airflow pattern. Alternatively, the nozzle can be flush with the surface of the finger. As another option, one or more additional nozzles can be incorporated into the upper surface of the finger, arranged in a predetermined array, and the nozzle or nozzles can be configured to discharge the flows of air therefrom in a predetermined pattern, such as a tightly focused rearwardly directed pattern, or a broader fan pattern, as determined at least in part by the effect sought to be achieved.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a top view of a combine including a header having an air discharge system for the sickle thereof, including air discharge nozzles incorporated into guards of the sickle, according to the present invention;
FIG. 2 is an enlarged fragmentary side view of the header of FIG. 1 , showing a representative sickle guard and a preferred manner of incorporation of the air discharge system of the invention into the guard, and illustrating discharge of air from a nozzle of the system and the effect thereof on loose grain above the sickle;
FIG. 3 is a simplified fragmentary top view of a representative sickle guard, illustrating a manner of incorporation of a nozzle of the system of the invention incorporated into an upwardly facing surface of the guard;
FIG. 4 is a fragmentary perspective view of a pair of guards for a sickle, showing elements of the air discharge system of the invention incorporated therein;
FIG. 5 is a fragmentary top view of the header, showing another embodiment of an air discharge nozzle usable with the system of the invention, and illustrating different air discharge patterns that can be achieved using different nozzles with the invention;
FIG. 6 is a top view of a pair of guards illustrating still another embodiment of air discharge nozzles usable with the system of the invention, and illustrating still different air discharge patterns achievable with the different nozzles;
FIG. 7 is an enlarged fragmentary partial sectional side view of a guard, illustrating a manner of incorporation of air flow passages and a nozzle of the system of the invention therein;
FIG. 8 is an enlarged fragmentary sectional side view of a guard, showing a nozzle, and illustrating discharge of a flow of air therefrom; and
FIG. 9 is a fragmentary top view of the guard of FIG. 8 , in partial section.
DETAILED DESCRIPTION OF THE INVENTION
Turning now to the drawings wherein several preferred embodiments of the invention are shown, in FIG. 1 , a conventional, well known agricultural cutting machine, which is a combine 20 , is shown including a header 22 . Header 22 is shown supported in the conventional, well-known manner on a forward end 24 of combine 20 , and is operable for cutting or severing crops such as, but not limited to, small grains such as wheat and soybeans, and inducting the severed crops into a feeder 26 for conveyance into combine 20 for threshing and cleaning, in the well known manner, as combine 20 moves forwardly over a field, as denoted by arrow F.
Referring also to FIG. 2 , which is a side view of header 22 , header 22 includes a pan or floor 28 which is supported in desired proximity to the surface of the field during the harvesting operation, and an elongate, sidewardly extending sickle 30 along a forward edge portion 32 of floor 28 , sickle 30 being operable for severing the crop for induction into header 22 , as will be explained. Header 22 additionally includes an elongate, sidewardly extending reel 34 (shown in outline form in FIG. 1 ) disposed above sickle 30 and rotatable in a direction for facilitating induction of the severed crops into header 22 . An elongate, rotatable auger 36 (also shown in outline form in FIG. 1 ) that extends in close proximity to a top surface 38 of floor 28 and has helical flights therearound is operable in cooperation with reel 34 for conveying the severed crops toward an inlet opening of feeder 26 for induction into combine 20 , in the well-known manner.
Referring more particularly to FIG. 1 , sickle 30 extends in a sideward direction along the width of floor 28 , between a first side edge portion 40 of the floor, and an opposite second side edge portion 42 . Sickle 30 includes an elongate, sidewardly extending cutter bar assembly 44 supported in substantially longitudinally aligned relation adjacent to forward edge portion 32 of floor 28 , along the length thereof.
Referring also to FIGS. 3 , 4 and 5 , cutter bar assembly 44 includes a plurality of forwardly extending, elongate guards 46 arranged in a sidewardly extending, spaced apart array, along the forward edge portion of header 22 . Each guard 46 is preferably of cast metal and includes a rearwardly located base 48 , which is suitably attached, here by a bolt 50 and a nut 52 , to a fixed bar 54 or other fixed structure of assembly 44 . Here, it can be observed that guards 46 are provided in pairs connected together by a crossmember, although it should be understood that, alternatively, they could be provided individually, or connected together in a greater number, with equal utility for the purposes of the present invention. Each guard 46 additionally includes a forwardly extending finger 56 attached to base 54 , finger 56 having a forwardly located forward tip 58 . Each finger 56 includes oppositely facing side surfaces 60 and 62 which extend forwardly from adjacent base 48 to tip 58 , and which taper convergingly as they approach tip 58 . Each finger 56 also includes an upwardly facing surface 64 which extends from base 48 to tip 58 . Each finger 56 includes a slot 66 extending therethrough between side surfaces 60 and 62 , intermediate base 48 and tip 58 , slots 66 of the respective fingers 56 being aligned along the length of sickle 30 .
Referring more particularly to FIGS. 2 and 5 , cutter bar assembly 44 supports an elongate sickle knife 68 for reciprocating longitudinal movement within slots 66 , knife 68 including a row of knife sections 70 including oppositely facing, angularly related knife edges 72 which, in conjunction with site surface 60 or 62 of adjacent guards 50 , respectively, effect a shearing or cutting action which severs plant stems and stalks or other material captured between the knives and the guards as the knife sections are reciprocatingly moved sidewardly, as denoted by arrow A in FIG. 5 . Guards 46 will typically extend beyond sickle knife 68 by no more than 12 inches, as it may be desired under some conditions to have a capability to point the guards downwardly at a small acute angle to the ground, for instance, with the sickle close to the ground, for harvesting downed crops, without the guard tips entering the ground. It is also desirable for the guards to have a smooth streamlined shape, which is relatively narrow, so as to smoothly guide the crops into the spaces therebetween, for cutting.
As noted above under the Background Art heading, as combine 20 is moved forwardly over a field containing crops, sickle knife 68 will be moved reciprocatingly sidewardly relative to guards 46 , to sever the crops which enter the spaces between guards 46 . Knife edges 72 will capture and cut the stems or stalks of the crop plants against the side surface 60 or 62 of the adjacent guard, in an area denoted as a cutting zone 74 illustrated in relation to the leftmost guard 46 in FIG. 5 . As a result of the cutting action, and particularly if the crop is dry and/or knife edges 72 are dull, and/or the side edge of the slot is worn and rounded, and also as a result of being batted by reel 34 , grain can be loosened from the crop plants, e.g., pods shattered, such that the loose grain will fall onto sickle 30 , and onto any plant material thereon, so as to be in danger of falling to the ground and being lost. Grain can also be shaken loose if the guards are large, or are not sufficiently streamlined for smooth crop flow therepast, or have obstructions that extend into the crop flow path, so as to shake or jar the crops as they are inducted into the sickle. This can be particularly problematic in drilled crops which lack defined rows and thus increase the possibility of guards 46 being propelled directly into plants during the cutting operation. Referring more particularly to FIG. 2 , loose soybeans 76 are depicted in the area above sickle 30 , as would be typically present during the harvesting of crops such as soybeans or other legumes, as well as other small grains. If not captured, at least some of loose grains 76 would typically be lost, for instance by falling through the spaces between knife sections 70 and guards 46 , or by falling forwardly over the front edge of the sickle.
To avoid or reduce the occurrence of grain loss in the above described manner, an air discharge system 78 is incorporated into some and preferably all of guards 46 of sickle 30 , according to the present invention. Air discharge system 78 includes at least one rearwardly facing air discharge nozzle 80 incorporated into upwardly facing surface 64 of each finger 56 , and an air flow passage 82 extending internally through each finger 56 from an air inlet 84 located adjacent to base 48 , to nozzle 80 , for delivering a flow of pressurized air thereto. The pressurized air is provided by a suitable source thereof, such as, but not limited to, an air pump or air compressor 86 disposed at a suitable location, such as on header 22 , and which is suitably powered, for instance, by a fluid motor, belt, shaft, chain, or the like, in the well-known manner. Compressor 86 is connected to air inlets 84 , for delivering pressurized air thereto, via an air distribution system which will preferably include a main air manifold 88 extending sidewardly beneath floor 28 of header 22 , and including a plurality of nipples or small air distribution tubes 90 emanating therefrom at appropriately spaced locations therealong corresponding to the locations of air inlets 84 . Smaller air distribution tubes 90 are shown extending from manifold 88 individually to air inlets 84 . Alternatively, it should be recognized that a variety of different air distribution system configurations can be utilized according to the present invention.
The configuration and location of air discharge nozzles 80 on surfaces 64 of respective fingers 56 can be varied according to the preferences and/or requirements for a particular application. Generally, it will be an objective of the invention for nozzles 80 to be minimally if at all obstructive to crop and plant flow over and passed fingers 56 , such that little or no resultant additional jarring or disturbing of the plants passing over the nozzle occurs so as to result in additional loosening of grain from the plants. Additionally according to the invention, an objective will be to generate rearwardly directed pressurized air flows that will be effective in blowing and directing loose grain on to floor 28 to capture the loose grain and prevent loss thereof. Further according to the invention, it will be an objective to minimize susceptibility of plugging of nozzles 80 by plant material and the like. Still further, it will be an objective when incorporating nozzles 80 and air flow passages 82 into fingers 56 , to maintain and not significantly degrade the structural integrity of the fingers, or to materially change the operability thereof. In accordance with the above objectives, several embodiments of nozzle configurations of the invention are illustrated in FIGS. 2 through 9 .
Referring more particularly to FIGS. 2 , 4 , 5 , and 7 through 9 , nozzles 80 are illustrated as rearwardly directed and recessed into upwardly facing surface 64 of fingers 56 . Of these, nozzles 80 of FIGS. 2 , 4 , 5 and 8 are circular shaped, and nozzles 80 of FIGS. 8 and 9 are diamond shaped. This represents a range of acceptable nozzles and is thus not intended to be limiting. Each nozzle 80 is also illustrated disposed at a forward end of a rearwardly extending recessed channel 92 , which, in cooperation with the nozzle configuration, facilitates and guides the pressurized air flow in a desired pattern, without significantly disrupting crop flow over upwardly facing surface 64 of the finger. However, it should be noted that other locations, including a more forward location, can be utilized according to the invention. Referring more particularly to FIG. 2 , the pressurized air flow, denoted by arrows 94 , is illustrated as flowing along a relatively low, rearwardly directed trajectory over sickle 30 and forward edge portion 32 of floor 28 . Referring in particular also to FIG. 5 , FIGS. 5 and 6 , Air flow 94 is also illustrated from the side in FIG. 8 . Here, it should be recognized that the configuration, including, but not limited to, size, shape, and angular orientation, of nozzles 80 can be determined for a particular application, as can the configuration, e.g., size, shape and angular orientation of the channel 92 if used. FIG. 5 illustrates possible air flow patterns that can be achieved with the nozzles of the invention, including a narrower pattern that generally extends over the base region of the guard in which the nozzle is located, as defined by lines 96 emanating from the respective nozzles, and a wider fan shape pattern that extends over a greater portion of the sickle knives also, as defined generally be lines 98 .
Referring in particular to FIG. 3 , a nozzle 80 which is substantially flush with surface 64 is shown, the nozzle having a generally oval or tear drop sectional shape when viewed from above. Again, this illustrates the variety of nozzle configurations that can be used according to the invention.
Referring more particularly to FIG. 6 , still another nozzle configuration is illustrated, which is a multiple nozzle arrangement including an array of three nozzles 80 disposed in surface 64 , facing in slightly offset directions, and configured to discharge streams of pressurized air in a wide ranging fan pattern, illustrated again by lines 98 emanating from each of the nozzles. Here, it should be noted that the number of nozzles, positions, and orientations, on a finger can be varied, as desired or required for a particular application.
In the fore and aft direction, nozzles 80 are preferably disposed so as to most advantageously direct the pressurized air for recovering or protecting from the loss of loose grain, without degrading the integrity and strength of the fingers. In the embodiments shown, nozzles 80 are generally located above a forward region of slot 66 through which the sickle knife reciprocates. To achieve this location, air flow passage 82 has a generally V shape, including a lower portion 100 which is routed forwardly through the finger below slot 66 , and an upper portion 102 which connects with lower portion 100 and extends rearwardly therefrom to the nozzle, or nozzles, as variously shown in the FIGS. Air flow passage 82 can be cast in place in the finger. Essentially, the fore and aft location selected here has been found to be advantageous as it places the nozzles close to the cutting zone where the largest portion of the loose grain has been typically found to be present, such that the air will be at its greatest pressure where the grain is found, and will be less likely to be dissipated by intervening plant material such as leaves, stems and the like which will be passing through the cutting zone also.
It will be understood that changes in the details, materials, steps, and arrangements of parts which have been described and illustrated to explain the nature of the invention will occur to and may be made by those skilled in the art upon a reading of this disclosure within the principles and scope of the invention. The foregoing description illustrates the preferred embodiment of the invention; however, concepts, as based upon the description, may be employed in other embodiments without departing from the scope of the invention. Accordingly, the following claims are intended to protect the invention broadly as well as in the specific form shown. | A guard for a sickle of an agricultural plant cutting machine includes a forwardly extending finger including a longitudinally extending, upwardly facing surface extending over the sickle, which includes a rearwardly facing air discharge nozzle therein located above and/or forwardly of the sickle, and the finger includes an air flow passage extending internally therethrough from an air inlet adjacent to a base of the finger to the nozzle, for delivering a flow of pressurized air thereto, the nozzle being at least mostly flush with or recessed into the upwardly facing surface. As a result, the nozzle is operable for discharging the flow of air rearwardly over the finger without obstructing plant material flow thereover, the air flow being sufficient to blow at least a substantial amount of loose grain and other plant material located forwardly of the front edge of a header floor of the machine, onto the floor for collection by a conveyor of the header for processing. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of U.S. patent application Ser. No. 13/482,062, filed May 29, 2012, which is a continuation of U.S. Pat. No. 8,186,383, filed Oct. 15, 2008, which is a U.S. national phase application filing of International Patent Application No. PCT/US2006/030399, filed Aug. 3, 2006, which claims the benefit of and priority to U.S. Provisional patent application No. 60/707,399, filed Aug. 11, 2005, the entire contents of each of which are incorporated herein by reference.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
None.
BACKGROUND OF THE INVENTION
Technical Field
This invention relates to a selector valve assembly. More particularly, it relates to a selector valve assembly which can regulate the flow of at least four different fluid materials in conjunction with a dispensing eductor.
Background Art
The use of selector valves in conjunction with eductors for mixing chemical concentrates into a stream of liquid to provide a diluted solution is well-known. For example, see U.S. Pat. Nos. 5,377,718 and 5,653,261.
While these selector valves can control and select four different chemical concentrates to be introduced into an eductor, there is a problem with residual carry-over when selecting from one chemical concentrate for another. This is caused by the use of the channeled disks 11 in the '718 and '261 patents.
All current selector valve systems which utilize two separate eductors to provide a high and low flow rate use two separate selector valves for each eductor. Not only does this add cost and complexity to the system, it makes the system easier for the end user to mishandle. They can have the selector valve pointed to one product of one eductor and accidentally fill a different product from the second eductor. These types of systems also require labeling of the dispenser for product identification which can also cause misuse.
There is a need for a selector valve which can be used in conjunction with an eductor mixing system which can reduce the incidence of product carry-over when a selector valve is moved from one position to another. There is also a need for a selector valve which can reduce costs and mishandling.
The objects of the invention therefore are:
a.) Providing an improved selector valve. b.) Providing an improved selector valve for use with a liquid mixing and dispensing apparatus. c.) Providing a selector valve of the foregoing type for use with an eductor. d.) Providing a single selector valve of the foregoing type which can accommodate two different eductors. e.) Providing a selector valve of the foregoing type which reduces the incidence of product carry-over. f.) Providing a selector valve of the foregoing type which employs a minimum number of parts and reduces incidence of improper dispensing. g.) Providing a combined selector valve and eductor assembly.
These and still other objects and advantages of the invention will be apparent from the description which follows. In the detailed description below, a preferred embodiment of the invention will be described in reference to the full scope of the invention. Rather, the invention may be employed in other embodiments.
SUMMARY OF THE INVENTION
The foregoing objects are accomplished and the shortcomings of the prior art are accomplished by the selector valve assembly of this invention which can control the flow of at least two flow paths of fluid. The selector valve assembly has a body member having a compartment with an end wall. There is an outlet passage in the end wall of the compartment and at least two passages communicate with the compartment. A rotatable member is sealably positioned in the compartment, the rotatable member having a side wall and an end wall. A first passageway extends a distance into the rotatable member from the end wall thereof. A second passageway extends through the side wall thereof and communicates with the first passageway. Rotation of the rotatable member will selectively orientate the second passageway with each of the at least two passages so as to cause liquid in the at least two passages to pass to the first and second passageways and subsequently to the outlet passage.
In a preferred embodiment, the selector valve assembly includes four passage ports connected to the body member and communicating with the second passageway in the rotatable member.
In one aspect, the selector valve assembly includes swivel ports connected to the body member and communicating with the four passages in the body member.
In another preferred embodiment, an indexing member is connected to the rotatable member.
In another aspect, the selector valve assembly includes a spring member in biasing contact with the indexing member and a spring retaining member connected to the body member and the spring member.
In yet another aspect, the selector valve assembly includes color indicator means operatively associated with each of the swivel port members.
In yet another preferred embodiment, there are two eductors connected to the outlet passage of the body member.
In still another preferred embodiment, two eductors are connected to the outlet passage of the body member by check valves.
In another aspect, a method of controlling the flow of different flow paths of fluid is provided. The method includes the steps of rotating a valve to a first position, receiving a first concentrate in the first position, discharging the first concentrate through one of two outlets, rotating the valve to a second position, receiving a second concentrate in the second position, and discharging the second concentrate through one of the two outlets.
In another aspect, a method of operating a selector valve assembly to control the flow of different flow paths of fluid is provided. The method includes the steps of rotating a member provided in the valve assembly between a plurality of positions, each position providing a fluid connection between one of a plurality of concentrates and a plurality of outlets, receiving one of the plurality of concentrates, and discharging one of the plurality of concentrates through one of the outlets.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view showing the selector valve assembly connected to two eductors;
FIG. 2 is an exploded view showing the component parts of the valve for interconnection to the eductors;
FIG. 3 is another exploded view showing the component parts for placement inside the valve body;
FIG. 4 is still another exploded view showing the valve selector indexing mechanism; and
FIG. 5 is a sectional view illustrating one position of the valve.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG. 1 , the selector valve assembly generally 10 is shown in conjunction with two eductors 12 and 13 . The preferred eductors are described in commonly owned patent application Ser. No. 11/195,052 filed Aug. 2, 2005 which teachings are incorporated herein. The selector valve assembly 10 includes a valve member 11 with a valve stem 14 housed in a tubular body member 15 to which is connected in a fluid tight manner four fluid intake ports 17 , each having nipples 19 .
As seen in FIG. 2 , the selector valve assembly 10 includes two check valve mechanisms generally 20 disposed between the valve member 11 and the eductors 12 and 13 . The check valves 20 include check balls 22 and 23 . A ball seating washer 26 and check ball guide 24 are also provided as well as a spring 28 . Sealing rings are also shown at 30 and 32 .
Referring to FIGS. 3 and 5 , valve member 11 is composed of valve stem retainer 35 which fits through slots 37 and 38 in body member 15 and over groove 40 in valve stem 14 to removably retain valve stem 14 in body member 15 . An indexing function is provided for the valve stem 14 by means of the indexing plate 42 and indexing receiver 44 . Spring 46 biases plate 42 against receiver 44 . Indexing receiver 44 is retained on valve stem 14 in a non-rotatable manner by the projections 45 in the body member 15 engaging the cut outs 47 in indexing receiver 44 . This is best seen in FIG. 4 where it is also shown the projections 43 on indexing plate 42 for riding over indexing receiver 44 and engaging the indents 41 . Indexing plate 42 rotates with valve stem 14 by means of the flat walls, one of which is shown at 49 and the flat side 51 of valve stem 14 .
As best seen in FIG. 5 , valve body member 15 has a compartment 58 in which valve stem 14 is seated. A seal ring is provided at 52 . It also has an end wall 60 . A side wall 62 is provided in valve stem 14 as well as an end wall 64 . A passageway 66 extends inwardly into valve stem 14 from the end wall thereof and joins passageway 68 which extends inwardly into valve stem 14 from side wall 62 .
As also seen in FIG. 5 , passages 18 are provided in intake ports 17 and passages 57 are provided in port housings 56 to provide fluid communication with compartment 58 as well as passageway 68 in valve stem 14 . Seal rings are shown at 54 . It will also be seen in FIG. 5 that body member 15 has eductor ports 71 which connect with eductor ports 70 of eductors 12 and 13 . Eductor ports 70 accommodate springs 28 in compartments 79 as well as check ball guides 24 . Passages 77 are disposed in eductor ports 70 and communicate with compartment 79 . Compartment 79 also accommodates check balls 22 and 23 as they are seated against valve seats 75 and 76 in body member 15 . A passage 78 is located in body member and communicates with passageway 66 in valve stem 14 as well as valve seats 75 and 76 .
Operation
A better understanding of the selector valve assembly 10 will be had by a description of its operation. Referring to FIGS. 1 and 5 , suitable sources of chemical concentrate are connected to intake ports 17 and nipples 19 such as with flexible tubing (not shown). It should be understood that eductor 12 has a faster flow rate than eductor 13 . Eductor 12 and hose 72 are employed to fill a bucket, whereas eductor 13 and hose 74 are employed to fill a bottle. When it is desired to fill a bottle, pressurized water is introduced into the inlet 80 of eductor 13 . This causes a siphoning effect on check ball 22 by means of passage 77 to move it away from the valve seat 76 to afford fluid communication with passage 78 and in turn passageways 66 and 68 . This provides a siphoning effect in intake port 17 to draw chemical concentrate into passage 18 , passageways 68 , 66 , passage 78 , compartment 79 , past intake portion 82 and into passage 77 , in that order. It is ultimately introduced into the water stream in eductor 13 in a well-known manner.
When it is desired to fill a bucket, pressurized water is introduced into the inlet 81 of eductor 12 . This causes a reduction in pressure on check ball 23 by means of passage 77 to move it away from valve seat 75 to produce a siphoning effect in passages 78 and passageways 66 and 68 as previously explained in conjunction with eductor 13 . This draws chemical concentrate into the eductor 12 and hose 72 as also previously explained. It should be noted that when a siphoning effect is produced on one of the check balls 22 or 23 , the other one is seated against its respective valve seal by means of spring 28 and the reduced pressure which moves open the other check ball.
When it is desired to introduce a different chemical concentrate in to the eductors 12 and 13 , valve stem 14 is rotated so that passageway 68 is orientated with a different intake port 17 . Rotation is facilitated by the indexing plate 42 which is spring loaded against indexing receiver 44 by means of spring 46 held captive in spring retainer 48 by clip 50 secured to valve stem 14 . Indexing between indexing plate 42 and indexing receiver 44 is accomplished in a well-known manner. This feature affords a positive locating of the valve stem 14 as well as an audible indicator.
In order to assure that the proper chemical concentrates are connected to the proper intake ports 17 , colored bands of different colors can be connected to intake ports such as shown at 84 in FIG. 1 .
An important feature of the selector valve assembly 10 are the passageways 66 and 68 in the valve stem 14 . These afford less carry-over from one chemical concentrate to the other as passageway 68 is moved from one intake port 17 to another. The reason for this is the cylindrical configuration of valve stem 14 acts as a seamless, continuous chemical pathway for either eductor 12 and 13 . The passageways 66 and 68 are preferably of 0.104 inch diameter which affords flow of maximum amount of concentrate with minimum amount of product carry-over. The combined volume of passages 66 , 68 and compartments 79 and eductor passages 77 is 0.635 ml. Also the common channel 78 between the check balls 22 , 23 and valve seats 76 , 75 respectively, is separated by less than 0.100″. This combined with the size of the compartments 79 for the check valves 20 and the size of eductor passages 77 minimizes retention of chemical concentrate.
Another important feature is serviceability. In order to service the revolving valve stem 14 or valve cylinder all that is required is to remove clips 50 and 35 . The stem 14 can be pulled straight out without removing the selector valve assembly 10 from the eductors 12 and 13 or removing the eductors 80 and 81 and valve assembly 10 from the water valves of a manifold. The spring retaining sleeve 48 connected to the valve stem 14 or handle prevents the clip 35 from backing out of position during use.
The valve assembly 10 allows for a single valve member for use with two eductors. This is a cost savings. It also provides for non unit labeling, where the product is it's own label and the selector valve points toward the intended product. This also allows for a single circuit if an electronic circuit is added for remote monitoring of chemical usage or electronic indicators (flashing lights, LED's, etc.) to further reinforce proper product selection.
The preferred material for manufacturing the selector valve stem 14 is Teflon®. The body member 15 is preferably manufactured from polypropylene.
However, other moldable plastic materials could be employed such as a polypropylene copolymer.
The detent on indexing plate 42 affords a stop and audible indicator for the position of the selector valve assembly 10 . If desired, it could be eliminated as could the color bands 84 . While the selector valve assembly 10 has been illustrated with four intake ports 17 for chemical concentrates, the selector valve can operate with fewer intake ports such as two, or a greater number such as eight. AU such modifications within the spirit of the invention are meant to be within a scope as defined by the appended claims. | A method of controlling the flow of different flow paths of fluid is provided. The method includes rotating a valve to a first position, receiving a first concentrate in the first position, discharging the first concentrate through one of two outlets, rotating the valve to a second position, receiving a second concentrate in the second position, and discharging the second concentrate through one of the two outlets. | 8 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a character recognition system and more particularly to a system in which alpha numeric characters may be hand written, with such characters being machine readable and also capable of being read as ordinary appearing alpha numeric characters.
2. Description of the Prior Art
As data processing equipment becomes more common, and the range of applications of such equipment increases, the problem of data entry assumes a more important aspect. In the past, it has been conventional to enter data by means of a key-punch machine, by which punched cards are produced through the efforts of a key-punch operator. More recently, key-to-tape and key-to-disk systems have become available, but they also require the use of a human operator whose function is solely to convert data from human readable form to machine readable form. This technique of data entry, requiring the use of a translator, is an obstacle to achieve an efficient data entry, and also represents a source of errors and inaccuracies.
Some machines have been devised to optically read certain kinds of print or typing, but these machines are not able to read characters written by hand, because of the lack of uniformity and size of such characters.
A great variety of machine readable families of characters have been devised in the past. These characters, with few exceptions, have generally not been equally well adapted for recognition by the human operator and for machine reading. The more suitable a family of characters is for machine reading, the less feasible it is to provide for visual recognition of the characters. The exceptions consist of families having relatively few characters. Although the familiar magnetically coded set of characters includes aliphatic characters as well as numerals, the alphabetic characters are rarely used, both because of their lack of similarity to conventional printed characters, and because of the difficulties encountered in decoding such characters. Moreover, the magnetically coded set is not adapted for being written by hand without the use of machinery especially constructed for that purpose.
While it is possible to train an operator to recognize esoteric symbols and codes which are designed primarily to be machine readable, such arrangements are not suitable for use by relatively unskilled persons, but are effectively restricted to highly skilled personnel or else require complicated coding machines.
In Siegal U.S. Pat. No. 4,132,976, a family of characters is described which is both operator-readable and machine-readable. While the system in that patent is adequate for a variety of purposes, the use of the system involves some limitations which it is desirable to overcome.
SUMMARY OF THE INVENTION
The principal object of the present invention is to provide a character recognition system in which a family of characters may be readily written and read by a human operator as well as by a machine.
Another object of the present invention is to provide such a system in which a relatively unskilled operator may readily and accurately enter input into a data processing system or the like, by means of written characters which are scanned in order to determine the presence or absence of portions of said characters coincident with discrete locations within a fixed array.
These and other objects and advantages of the present invention will become manifest upon an examination of the following description and accompanying drawings.
In one embodiment of the present invention there is provided a character recognition system comprising scanning means for optically scanning each of nine discrete primary positions within a 3×3 array, and four secondary discrete positions within said array, each of said secondary positions being surrounded by four primary positions, means responsive to said scanning device for determining the presence or absence of handwriting at each discrete position within said array, and output means for manifesting a character corresponding to the scanned array.
BRIEF DESCRIPTION OF THE DRAWINGS
Reference will now be made to the accompanying drawings in which
FIG. 1 is an illustration of a first embodiment of the background array;
FIG. 2 is an illustration of an alternative background array;
FIG. 3 is an illustration of the letter H appearing on a background array;
FIG. 4 is an illustration of the letter N appearing on a background array;
FIG. 5 is a functional block diagram of a system for scanning and recognizing marks within the discrete positions of the array.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG. 1, a background array is illustrated which incorporates the first embodiment of the present invention. An area 10 of the background array has nine primary discrete positions 12 and four secondary discrete positions 14. The positions 14 are arranged in a 3×3 matrix, forming four juxtaposed squares, and the four secondary positions 14 are located in the middle of each of the four squares, surrounded by four primary positions 12.
The described arrangement is replicated over a sheet of paper or the like which comprises a form facilitated in the entry of data onto the paper by a human operator. Data is entered onto the form by writing with pen and ink characters in a normal way such as the H and N illustrated in FIG. 3 and 4 respectively. It will be seen that the lines forming the characters pass through some of the discrete positions and not others, and sensing the discrete positions associated with the lines of the drawn characters identify such characters completely.
It is to be observed in FIGS. 3 and 4 that the H and N pass through the same primary positions, and may be distinguished only because the N passes through two secondary positions as illustrated.
FIG. 2 shows an alternative arrangement of the present invention, in which additional secondary positions 16 and 18 are illustrated. The secondary positions 16 are located on the right hand edge of the area 10, which is in common with the left hand edge of the corresponding area located immediately to the right of the area 10. The secondary positions 18 are located at the bottom edge of the area 10 which is also the top edge of the corresponding area immediately below the area 10. From FIGS. 1 and 2 it is apparent that the specific character areas such as the area 10 of the background array are discrete, and surround each group of secondary positions 14 and the symmetrically located primary positions which surround them. By contrast, the character areas of the background array shown in FIG. 2 are not discrete. The character area 10 may be formed of any nine primary loctions arranged in a square, as illustrated. Thus, while the background array illustrated in FIG. 1 assists in the entry of data in straight lines, and results in entered data in regular rows and columns, the background array of FIG. 2 facilitates different spacings between horizontal lines of characters when desired, and also facilitates different spacings between the characters themselves. In addition, the background array of FIG. 2 facilitates subscripts and superscripts, when the character areas 10 are not all located on the same horizontal line, but are offset upwardly or downwardly from such line.
FIG. 5 illustrates diagramatically, equipment for reading characters which are written using the present invention. The background array 20 supported on a support member 22, and light (reflected or transmitted) is received by a photo-sensitive element 24 from a primary or secondary position of the array through an optical system incorporated in a lens 26. The photo-sensitive device 24 is mechanically moved relative to the surface 20 by means of a scanning unit 28, so that the primary and secondary positions of the character area are scanned in sequence, with the output line 30 of the photo-sensitive device 24 producing a binary signal indicating whether each position contains a mark or not a mark. The line 30 is connected to the input of an output decoder 32 which supplies the output terminals 34 binary coded signals indicative of the character within the character area being scanned. The output decoder 32 is a data processing system for identifying characters recognized from the signals on the line 30. Reference is made to the aforesaid Siegel U.S. Pat. No. 4,132,976 for details concerning the mechanical, optical and electrical systems. The disclosure of the Siegel U.S. Pat. No. 4,132,976 is hereby incorporated by reference into this specification.
The details of the specific units employed for the optical, mechanical and electrical functions of the apparatus shown in FIG. 5 form no part of the present invention.
Although only two hand drawn letters are shown in FIGS. 3 and 4 of the drawings, it will be appreciated that a number of additional hand drawn letters will pass through some of the secondary positions, so that the secondary positions may be employed to identify such a character within a character area being scanned. Although the background array is of greater complexity than that described in the aforementioned Siegel U.S. Pat. No. 4,132,976, it is not so complex as to afford difficulties to a human operator using the background array to form individual characters in the usual manner, such as the H and the N illustrated in FIGS. 3 and 4. Other characters may be formed in the way illustrated in the aforementioned Siegel patent, and it will be apparent which of such characters have lines passing through the secondary positions.
The character set used with the present invention is not limited to any particular character set, but the character set illustrated in the aforementioned Siegal patent may be used if desired, or a restricted portion of such character set may be used in situations which do not require the use of every member of the character set. It will be found that some of the characters of a character set are restricted to lines which pass through primary positions only, in that event, it is not necessary to scan the secondary positions at all, thereby increasing the speed at which written information may be scanned. An example of such a character is the letter T, which uses only the top three primary locations of the top row and the center location of the second and third rows of a character area. In the character set described in the aforementioned Siegel patent, the combination of primary locations employed for the letter T is unique, and no secondary locations need be scanned in order to allow the letter T to be machine readable. In contrast, although the letter H uses only primary locations, the letter N uses the same primary locations and it is therefore necessary to scan secondary locations in order to distinguish a H from N. Therefore, the selective scanning of secondary locations, when necessary to resolve an ambiquity resulting from two or more characters sharing the same combination of primary locations, results in the possibility of substantially increased scanning speed without sacrificing the extra resolution obtainable through use of the secondary locations.
The areas within the primary and secondary locations of the background array are the only areas of the character bearing surface which are scanned. Accordingly, the presence of a mark or not a mark in any other area of the surface is not significant to recognition of the characters thereon. Accordingly, any foreign matter present on the surface bearing the characters outside the primary and secondary positions is ignored, and of no significance in the recognition of the characters. This makes it possible for an operator to make marks on the character bearing surface if desired, with the knowledge that such marks will be ignored during the machine reading process. Such marks may constitute for example, underlining of certain characters, or lines encircling one or more characters. Restricting scanning only to the areas within the primary and secondary locations decreases the sensitivity of the machine reading system to noise resulting from extraneous marks on the character bearing surface.
The primary and secondary locations are identified by circles in the embodiments illustrated in FIGS. 1 and 2, but they may be other shapes such as squares or triangles if desired for any reason. If desired, the locations may be printed in the form of circles or other shapes on the character bearing surface to guide a human operator in making a character which passes through the appropriate primary and secondary locations. If desired, the ink with which such positions are printed may be of a color which is invisible to the photo-sensitive device 24 used during scanning. Otherwise they are printed uniformly to provide the same background signal input to the photo-sensitive device 24.
The size of the circles or other shapes defining the primary and secondary locations may be of a different size than that illustrated. Increasing the size of the circles facilitates data entry, by making the appropriate circles easy to hit when an operator is entering data manually. Reducing the size of the circles increases the signal to noise ratio during machine reading, and facilitates distinguishing primary and secondary locations which have lines through them from those that do not. A compromise between these considerations leads to the use of circular areas for the primary positions which are spaced from each other by a distance equal to their diameter.
It will be apparent that various modifications and additions may be made in the apparatus and methods of the present invention, which are intended to be defined and secured by the appended claims. | A character recognition system incorporating a matrix of nine primary locations and four secondary locations, has a family of operator readable and machine readable alpha-numeric characters formed in relation to the matrix. Characters are designated by marking or not marking selected ones of the primary and secondary locations. The primary locations are scanned first to determine whether the combination of primary locations which is marked determines a single character. If not, the secondary locations are scanned to determine a unique character. | 6 |
The present invention concerns the connection of tubing components to pipes, and has particular relevance to air-conditioning systems.
The global market for air-conditioning systems has risen dramatically in the last decade and looks set to continue to expand, for example into Eastern Europe. Currently, the most advanced air-conditioning system in common use is the VRV or Variable Refrigerant Volume system. This system comes in two types: “cooling only” which is a two-pipe system, or a three pipe system which performs cooling and heating providing heating through recognised heat-pump technology.
A network of pipes is installed around the building to supply refrigerant to the relevant cooling coils (“air handlers”) in the required areas. FIG. 1 shows a known apparatus for assembly into such a network. A metal tubing component 1 is shown as a bifurcated Y-shaped junction to be connected to a metal pipe 2 . The tube component 1 comprises several sections of different diameter, for example the first branch of the junction has two in-line sections X 1 and X 2 , while the second branch has three in-line sections: Y 1 , Y 2 and Y 3 to enable the component to be fitted to various standard, i.e. commercially accepted, sizes of pipe 2 . When the component is to be fitted, the diameter of pipe 2 is determined and the correct diameter section of the component 1 is used to enable the pipe 2 to be accommodated within the section. In the figure shown, section X 2 has the correct diameter to allow pipe 2 to be inserted within it. If however pipe 2 was wider, then section X 1 would have to be used. In that case, the component would be cut off at section X 1 to allow insertion of the pipe 2 . To fix the pipe 2 within the end section of component 1 , the pipe and section are welded together. This is a cumbersome operation, especially since it is necessary to purge the weld region with nitrogen in order to prevent oxidation of the metal. Accordingly, the connection of tubing component 1 to pipe 2 is intricate and subsequently expensive and prone to error and fire risk, and takes an excessively long time to complete.
It is an object of the present invention to provide a connection kit and method which overcome the above problems. This is achieved by the use of cold jointing means with a correspondingly resized tubing component.
SUMMARY
In accordance with a first aspect of the present invention there is provided a kit of parts comprising a tubing component having at least two in-line sections with different external diameters and a set of connection means, each connection means having dimensions such that it may be joined to the tubing component at a respective section.
Preferably, each connection means comprises a locking ring.
The kit of parts may be used in fabricating an air-conditioning system.
In accordance with a second aspect of the present invention there is provided a method of connecting a tubing component to a pipe comprising the steps of:
providing a tubing component with at least two in-line sections with different external diameters; selecting a section with a substantially similar diameter to that of the pipe; if the selected section is not at an end of the tubing component, cutting the tubing component in the vicinity of the selected section so that the selected section is at an end of the tubing component; providing a set of connection means in a range of sizes; selecting a connection means of suitable dimensions for joining to the selected section; and joining the selected connection means to the tubing component at the selected section.
Preferably, each connection means comprises a locking ring.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will now be described by way of example with reference to the following figures, in which:—
FIG. 1 shows a conventional pipe assembly;
FIG. 2 shows an unconnected apparatus according to an embodiment of the present invention; and
FIG. 3 shows the apparatus of the embodiment of FIG. 2 in a connected state.
DETAILED DESCRIPTION
Referring now to FIGS. 2 and 3 , an assembly is shown according to an embodiment of the invention. Starting with FIG. 2 , again it is desired to connect a tubing component 1 ′ to a pipe 2 . The tubing component 1 ′ again comprises several sections of various external diameters, for example the in-line sections X 1 ′, X 2 ′, X 3 ′ and X 4 ′ of a first branch and in-line sections Y 1 ′, Y 2 ′ and Y 3 ′ of a second branch. However, with this embodiment the diameters of the sections are set to be standard, i.e. commercially accepted and available, sizes. Since the pipe 2 is also of a standard diameter, it is possible to select a section which has the same diameter as the pipe 2 . In the example shown in the figure, section X 2 ′ has the same diameter as the pipe, and therefore the component is cut at section X 2 ′ as shown. Clearly it is also possible to select a section of the second branch to enable this branch to be connected also.
Connection between the component 1 ′ and pipe 2 is achieved by use of a connection means 3 , which in the present embodiment comprises a locking ring. A suitable locking ring for this purpose is for example manufactured by Vulkan Lokring, Rohrverbindungen GmbH & Co. KG of Herne, Germany. Connection is achieved by inserting the ends of the pipe and component into the locking ring as shown, the ends being covered with a sealing preparation beforehand if necessary. A compression device is then used to squeeze the two end rings 4 of the locking ring together, which compresses the ends and holds them tightly and sealingly within the connection means. The compression device will preferably comprise a manually operable tool, which uses a ratchet arrangement to assist the user in forcing the rings together. A powered compression device is also available, and both of these devices are manufactured by Vulkan Lokring for example. The connected assembly is shown in FIG. 3 .
The advantage of using such a connection means is that the join can be done cold, i.e. without welding, thus reducing the complexity, time and cost of the assembly operation. Furthermore, no expensive or complex equipment is needed to fit the connection means.
A plurality of connection means of different sizes will be provided, allowing the tubing component to be fitted to a variety of sizes of pipe by appropriate selection of component width section and connection means.
Although the invention has been described with reference to the embodiments above, there are many other modifications and alternatives possible within the scope of the claims. For example, any suitable cold connection means may be used in place of the locking ring. | A kit of parts includes a tubing component having at least two in-line sections with different external diameters and a set of connection devices. Each connection device is dimensioned such that it may be joined to the tubing component at a respective section. | 8 |
FIELD OF THE INVENTION
The present invention relates to updatable optical data storage discs.
BACKGROUND OF THE INVENTION
Optical discs, such as CD-ROM (Compact Disc-Read Only Memory) or DVD-ROM (Digital Versatile Disc) media, have data stored as a series of lower "pits" formed within a plane of higher "lands". The pits are arranged in a spiral track originating at the disc's center hub and ending at the disc's outer rim. The CD-ROM and DVD-ROM formats allow for discs that are inexpensive to produce yet have high storage densities. DVD-5, which was launched in 1997, has a diameter of 120 mm and a capacity of 4.7 gigabytes (GB). However, such discs are pre-recorded and cannot be recorded on by the end user.
Rewritable optical discs typically come in the form of magneto-optical or phase-change discs. DVD-RAM (random-access-memory) are rewritable phase-change discs. These discs have a spiral tracking groove comprised of pits having a depth of about λ/4 n, or about 103 nm for a laser wavelength, λ, of 650 nm, and a refractive index, n, of 1.58. Data may be recorded by the end user in the grooves.
In phase-change discs, the recording layer is a material that can exist in two different solid phases. The material can be switched from one stable phase to another by appropriate heating by a read/write laser. Typical phase-change materials are multicomponent alloys that have a stable, compatible, crystalline phase and a metastable amorphous phase with different optical properties, namely, a different coefficient of reflectivity, R. Recording is accomplished by locally melting the recording material and then cooling it quickly enough to quench it in the amorphous phase. The material in the amorphous state (i.e., the recorded bit) can be erased by annealing by heating the bit to a temperature for a long enough period of time to recrystallize the bit. Typical phase-change materials include GeTeSb and AgInTeSb.
The specification for DVD-RAM as of August 1997 calls for a capacity of 2.7 GB. DVD-RAM discs contain no pre-recorded data (other than servo and/or format information). If any such data were recorded prior to sale to the end user, such data would detract from the 2.7 GB of recordable storage available to the end user.
SUMMARY OF THE INVENTION
It would be desirable to have an updatable phase-change disc which had the advantages of both the data densities associated with standard pre-recorded discs such as DVD-ROM as well as the recording capacity of rewritable optical media, such as DVD-RAM.
Accordingly, the present invention is directed to an updatable optical data storage disc for use with a laser having a wavelength λ. The disc includes a substrate containing pre-recorded information in the form of concentric or spiral tracks of pits and a recording layer on the pitted side of the substrate. In unrecorded portions of the recording layer, light from the laser reflected from the recording layer has a first phase, P 1 , and a first reflectivity, R 1 . In recorded portions of the recording layer, light reflected from the recording layer has a second phase, P 2 , and a second reflectivity, R 2 . The absolute value of the difference between the two phases (|P 1 -P 2 |) is preferably in the range of 30°-100°, more preferably 40°-80°, and most preferably 50°-70°. The difference between the two reflectivities (R 1 -R 2 ) should be minimized, and in any event should be less than 40% of the average of the two reflectivities 0.4 ((R 1 +R 2 )/2), more preferably less than 20%, and most preferably less than 10%. R 1 and R 2 are each preferably in the range of 15 to 40°.
The disc may be designed for use with a substrate-incident optical system. The recording layer is preferably in a crystalline state in unrecorded portions and an amorphous state in recorded portions. The recording layer preferably has a thickness within the range from about 20 to 40 nm. One preferred material for the recording layer is TeGeSb.
In one preferred embodiment, recordable tracks are positioned adjacent the pre-recorded tracks, whereby the tracks on the disc alternate in the radial direction between pre-recorded and recordable information. The disc preferably includes dielectric layers on each side of the recording layer.
The wavelength λ of the laser is preferably in the range of 400-800 nm. The pits should have a depth in the range of λ/8 to λ/4 (typically 80-140 nm depending on the wavelength), more preferably about λ/6.
In a preferred embodiment, in the land portions between the pits in a pre-recorded track, light reflected from the optical stack has one phase, P 3 , while light reflected in the pits has another phase, P 4 . The absolute value of the difference between the two phases (|P 3 -P 4 |), is preferably in the range from 120° to 240°, more preferably 160° to 200°. Usually, P 3 , the phase for light reflected in the land areas between the pits in each pre-recorded track, will be substantially equal to P 1 , the phase for light reflected in the unrecorded portions of the recordable tracks between the pre-recorded tracks.
The present invention also includes a method of reading the updatable storage disc described above. A laser beam is directed onto the pre-recorded tracks and deflected by a split detector having two detectors parallel to and aligned with the length of the pre-recorded tracks. The split detector generates a signal using the sum of the measured outputs of the detectors, thereby reading the data in the pre-recorded tracks. For the recordable tracks, the split detector generates a signal using the difference between the measured output of the two detectors. Data may be recorded in the recordable tracks by increasing the intensity of the laser to locally melt the recording layer and cooling the bit quickly enough to quench it in the amorphous state.
The present invention also includes a drive for the disc described above. The drive includes a laser, a split detector, and two sets of electronics. The laser is operable at a first energy level to read data on the disc and a second, higher energy level to write data in the recordable tracks. The split detector includes at least two detectors parallel to and aligned with the length of the pre-recorded tracks and spaced from each other such that one detector receives light reflected from a leading edge of the laser beam on a recorded bit while another detector receives light reflected from a trailing edge of the laser beam. The first electronics generates a first signal using the sum of the measured outputs of the detectors, thereby allowing the drive to read data in the pre-recorded tracks. The second electronics generates a second signal using the differential of the measured outputs of the detectors, thereby allowing the drive to read data in the recordable tracks.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 shows an overhead view of a portion of a disc according to the present invention.
FIG. 2 shows a cross-sectional view of the disc of FIG. 1 taken along the lines 2--2.
DETAILED DESCRIPTION
An updatable optical data storage disc 10 according to the present invention is shown in FIG. 1. Disc 10 includes a spiral or concentric pattern of pits A containing pre-recorded data, as well as other information such as tracking, servo, and format information. Data may be recorded by the end user in data tracks B which are provided between data pit tracks A.
A cross-sectional view of disc 10 taken along line 2--2 is shown in FIG. 2. Disc 10 comprises a substrate 12, a first dielectric layer 14, a recording layer 16, a second dielectric layer 18, and a reflecting layer 20. Additional layers may be provided over reflecting layer 20, such as a protective layer.
Laser beam 30 directs light beams C and D (but not both simultaneously) toward disc 10 and through substrate 12. Light beams C and D are reflected by the stack of layers and reflecting layer 20 toward split detector 40, which detects reflected light intensity. Split detector 40 comprises at least two detectors, but may include four detectors or more. The at least two detectors should be oriented such that a line connecting the centers of the two detectors is parallel to and aligned with the track it is reading/writing. In other words, each detector would be reading the same track but would be spaced from each other along the track direction. This spacing is such that one detector receives light from the leading edge of the laser beam on the recorded bits while the other detector receives light from the trailing edge of the laser beam. Laser 30 may track on either of data pit tracks A or recordable tracks B.
When laser 30 follows data pit tracks A, laser beam C strikes and is reflected at reflecting layer 20 over the data pits or lands between adjacent pits in a given data pit track A. The pits have a depth of about λ/4 n, where λ is the wavelength of laser beam 30 and n is the refractive index of substrate 12. For DVD products, the substrate is polycarbonate which has an index of refraction n of 1.58 and the laser beam has a wavelength λ of 650 nm and thus the pits should have a depth of about 650 nm/4(1.58) or about 103 nm. For most substrates 12, the product of 4 n is about 6. This pit depth is selected so that the difference in the beam path length between a beam which strikes a pit and a land is equal to 2λ/4 n, or λ/2 n. This ensures that the two beams are 180° out of phase, enabling easy detection of changes in light intensity at split detector 40. The information in data pit tracks A is then read by split detector 40 using the sum of the signals received from each of the two detectors ("the sum channel").
When laser 30 follows data tracks B, laser beam D is reflected by the optical stack in substrate 12 and data recorded by the user may be read by split detector 40 using edge detection. Light reflected from bits that are in one state (e.g., unrecorded bits), has a given reflectivity, R 1 and phase P 1 , and light reflected from bits in a second state (e.g., recorded bits) has a second reflectivity, R 2 , and a second phase, P 2 . The information in recordable data tracks B is then read by split detector 40 using the difference between the signals received from each of the two detectors ("the difference channel"). Bits may be recorded in recordable data tracks B by laser 30 in the conventional manner, i.e., by using laser 30 at a higher intensity to locally melt the recording material and cooling it quickly enough to quench it in the amorphous phase.
The phase-change material that comprises recording layer 16 is chosen so that the change in phase (ΔP) of light reflected from unrecorded bits (P 1 ) and recorded bits (P 2 ) is within the range from 30°-100°, more preferably from 40°-80°, and still more preferably about 50°-70°. It is also desirable to minimize the difference in reflectivity, R, between the unrecorded bit (R 1 ) and the recorded bit (R 2 ). The difference between the two reflectivities (ΔR) is preferably less than 40%, and more preferably less than 20% of the average of R 1 and R 2 , i.e., ##EQU1## The reflectivities R 1 and R 2 are preferably within the range of 15-40%.
As explained above, the depth of the pits in data pit tracks A is about λ/4 n, so that there is a phase shift of about 180° between light reflected by the pits or the lands between the pits. Although a phase shift of about 180° is desired, a phase shift within the range of 120°-240° is sufficient, although a range of 160°-200° is preferable.
The ranges for the phase shifts between the pit and land (preferably about 180° but possibly between 120° and 240°) and the unrecorded and recorded bits (preferably between 50° and 70°) are chosen so that they do not overlap. This minimizes the likelihood of cross-talk, i.e., undesired signal from the neighboring track. By minimizing cross-talk, it is possible to arrange adjacent data tracks more closely together without the danger that the laser measured signal will be adversely affected by nearby data tracks. By decreasing the spacing between adjacent data tracks, it is possible to increase the storage density of a given disc.
Preferred materials for the components of disc 10 will now be discussed.
Substrate 12 is preferably transparent, has very low birefringence, and is nominally 0.6 to 1.2 mm thick depending on the product implementation. Suitable materials include glass, polymethylmethacrylate (PMMA), polycarbonate, and amorphous polyolefin (APO).
Dielectric layers 14 and 18 preferably comprise a dielectric material such as yttrium oxide, aluminum oxide, silicon carbide, silicon nitride, or silicon dioxide. Dielectric layers 14 and 18 typically have thicknesses in the range of 5 to 100 nm.
Recording layer 16 may comprise a rewritable recording material or a write-once material. For a write-once application, suitable materials for recording layer 16 include eutectic alloys, dye polymers, ablative, and bubble-forming materials. For rewritable applications, the material must be capable of undergoing a change in its optical properties (e.g., phase change) during the recording process. Preferred materials for a rewritable recording layer 16 include GeTeSb and AgInSbTe. The thickness of a phase-change recording layer 16 is preferably within the range of about 20-40 nm.
Reflecting layer 20 preferably has a high reflectivity, such as AlCr.
Although the present invention has been described with respect to pit depths designed to create a phase shift of about 180° and recordable materials designed to create a phase shift of about 50°-70°, those skilled in the art will appreciate that this invention could also be implemented by interchanging these values, i.e., by using pit depths which cause a phase shift of about 50°-70° and by using recordable materials which cause a phase shift of about 180°.
The invention will now be further illustrated by the following non-limiting Example. All measurements are approximate.
EXAMPLE
An updatable DVD-ROM was constructed of the following materials:
______________________________________Material Thickness______________________________________glass substrate 1.2 mm(ZnS).sub.0.8 --(SiO.sub.2).sub.0.2 10 nmGe.sub.0.22 Te.sub.0.56 Sb.sub.0.22 30 nm(ZnS).sub.0.8 --(SiO.sub.2).sub.0.2 44.5 nmAl.sub.0.97 Cr.sub.0.03 100 nm______________________________________
The glass substrate had pre-recorded information in the form of pits having a depth of about 83 nm and a track pitch of 0.72 μm.
The pre-recorded information on the disc was read by a 635 nm wavelength laser directed at data pit tracks A and detecting the reflection of the beam with a split detector using the standard sum channel. The resultant oscilloscope eye pattern was such that a standard DVD-ROM drive would be able to distinguish between the signal and background noise.
The laser was then directed toward the region between adjacent pit tracks (i.e., recordable tracks B) and the resultant signal using the difference channel of the split detector was measured, thus measuring the cross-talk between the recordable track B and the two adjacent pre-recorded tracks of pits A. The cross-talk from the pre-recorded tracks was measured to be at least 30 dB smaller than the signal from the pre-recorded tracks, indicating that there was minimal interference from the adjacent pre-recorded tracks.
While still tracking on the recordable track B, various frequencies of square wave tones were recorded. The recordable track B was then read with the laser and split detector using the difference channel. For mark lengths of 0.52 μm and larger, the measured carrier-to-noise ratio (CNR) was greater than 40 dB.
The laser was then redirected toward adjacent pre-recorded tracks A to see if the recorded signal in the recordable tracks B interfered with the reading of the signal from the pits in the pre-recorded tracks. No signal (i.e., less than 5 dB) was observed in the sum channel at the frequency of the recorded tone in the neighboring recordable track. | An updatable optical data storage disc for use with a laser includes a substrate and a recording layer. The substrate contains pre-recorded information in the form of concentric or spiral tracks of pits. Recordable tracks are positioned between adjacent pre-recorded tracks, whereby the tracks on the disc alternate in the radial direction. Laser light reflected from the recorded portions of the recording layer has a different phase than does light reflected from the unrecorded portions. This phase difference must be significant enough to be sensed by the detector. The difference in the reflectivity of the unrecorded and recorded portions of the recording layer should be minimized. The invention also includes a method and drive compatible with the disc. | 6 |
This application claims priority from Provisional Application No. 60/222,182 filed Aug. 1, 2000, which is herein incorporated by reference.
FIELD OF THE INVENTION
The present invention relates generally to an optical diffuser and method for making the same, and more particularly to an optical diffuser having a high diffraction efficiency, broadband response and cost effective method of producing the same.
BACKGROUND
Reflective diffusers are required for many applications, including liquid crystal displays, to enhance their viewability. Often these diffusers, placed behind the liquid crystal element, are simply roughened reflective surfaces. These reflectors utilize no back lighting, but instead rely on the scattered reflection of the ambient light. Unfortunately, light scattered from these devices is centered around the glare angle, which is in direct line-of-sight with the undesirable reflections from their front surface. Furthermore in many applications, such as computer screens, and perhaps watches, the preferred orientation of the device is one for which viewing at the glare angle is not optimum. The situation can be improved by using holographic diffusers which allow the reflection angles of interest to be offset, so that the maximum brightness from the diffuser falls in a preferred viewing angle which is different from that of the glare. One type of holographic diffuser that is sometimes used is the reflective, “surface-relief” hologram. This hologram has the advantage over other types in that if the ambient light is white, the reflected diffuse light is also white. Another advantage of the surface-relief hologram is that embossing can reproduce it easily and inexpensively. A major disadvantage is that the surface-relief hologram can be inefficient. Only a relatively small percentage of the incident light is diffracted into the desired viewing angles (typically less than 30 degrees)
A non-holographic diffuser, when coupled with a reflective focusing screen, uses randomly sized and randomly placed minute granules, which are created by interaction of solvent particles on plastic surfaces (See U.S. Pat. No. 3,718,078, entitled, “Smoothly Granulated Optical Surface and Method for Making Same”). These granules are dimples of extremely small magnitude (one half of a micron in depth), which reflect incident light more or less uniformly over a restricted angle. However, the angles of reflectance are very small, usually about + or −3 degrees, and the light reflected from them is here again at the glare angle.
A second kind of off-axis, holographic diffuser in common use today is the volume reflection diffuser, which can be provided by Polaroid Corporation of Cambridge Mass. With volume holograms, fringes that give rise to the diffuser reflection are distributed throughout the volume of the material, unlike the surface reflection concept of the “surface-relief” holograms. Because of this, light of a wavelength that is characteristic of the spacing distance between the fringe planes is resonantly enhanced over all other wavelengths. Thus, the reflected light is highly monochromatic. For example, if the spacing is characteristic of green, then green will be the predominant reflected color for incident white light. Unlike conventional embossed holographic diffusers, the reflection can be extremely efficient, although only over a narrow wavelength band. As a result, the surface-relief hologram can appear dim because most of the incident white light falls outside of this select band. Further processing can increase the bandwidth, thus increasing the apparent brightness, but the resulting diffuser still has a predominant hue, which is in most cases undesirable. In any event the bandwidth is still somewhat restricted, thus limiting the reflection efficiency.
Therefore, an unsolved need has remained for a diffuser having a high diffraction efficiency, broadband response and cost effective manufacture, which overcomes limitations of the prior art.
SUMMARY OF THE INVENTION
In an embodiment of the present invention as set forth herein is a blazed diffuser, which includes a reflective surface having a sawtooth structure. The sawtooth structure includes a series of contiguous wedges, each of which reflects incident oblique light into a beam which is more or less normal to the gross surface of the device. This wedge structure may be regarded as simply an off-axis mirror if the wedge spacing (period) is much larger than the wavelength. Superimposed on this wedge surface is a second structural component, which by itself diffracts incident light normal to its surface into rays, which constitute only those over a restricted narrow angle (e.g. + or −15 degrees). This angle is specified as that which is desired for a particular application. In an embodiment, this second surface shape is one that uniformly scatters an incident ray throughout the viewing angle. Such a structure gives a so called “flat top” scattering. When these two structures are superimposed, light incident from a predetermined angle which is dependent on the wedge angle, is uniformly scattered throughout a specified range of viewing angles with a high degree of efficiency. Almost all incident light is utilized and efficiencies approaching 100% for all visible wavelengths are possible.
In another embodiment, a blazed diffuser is made entirely by optical, holographic means, and it can be fabricated in such a way that the broadband spectral colors are properly mixed so that the diffracted light appears white. The recording for this diffuser is done in two primary ways. The first is by recording directly from a predetermined diffuse surface, and the second is by copying from a volume diffuser into a surface diffuser.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing and other objects of this invention, the various features thereof, as well as the invention itself, may be more fully understood from the following description, when read together with the accompanying drawings in which:
FIGS. 1A, 1 B and 1 C show a number of embodiments of the diffuser in accordance with principles of the present invention;
FIGS. 2A, 2 B, 2 C, 2 D, 2 E and 2 F show a number of embodiments of reflective surfaces associated with the embodiments of the diffuser shown in FIGS. 1A, 1 B and 1 C;
FIG. 3 shows the flat top diffraction profile of the surface of FIG. 2E;
FIG. 4 shows the diffraction profile of a surface which approximates that of FIG. 2E;
FIG. 5 shows the efficiency of light reflected for the structure of a preferred embodiment;
FIG. 6 shows light rays passing into and out the diffuser shown in FIG. 1A;
FIG. 7 shows interference fringe planes and the etched surface in photoresist of an embodiment of the diffuser;
FIG. 8 shows a recording configuration of an embodiment of the diffuser that uses prism coupling;
FIG. 9 shows a method for copying from a volume diffuser into photoresist using prism coupling;
FIG. 10 shows a method for making a deep stepped wedge structure by using a prism coupling;
FIG. 11 shows a recording configuration for adding diffuse reflectance to a stepped wedge structure using prism coupling;
FIG. 12 shows a recording configuration for making a fine interference fringe structure parallel to a recording surface by means of prism coupling;
FIG. 13 shows interference fringe planes and the etched surface in photoresist of a deep stepped wedge structure; and
FIG. 14 shows a theoretical diffraction efficiency for a ten-step wedge grating structure with step height=250 nm.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention provides an improved diffuser having a high diffraction efficiency, broadband response and method for making the same.
Referring to FIG. 1A, an embodiment of the present invention as set forth herein comprises an improved diffuser including a reflective surface. The reflective surface may include a periodic wedge structure 1 , as shown in FIG. 1A, which reflects incident light 2 so that incident light 2 impinges on its surface 3 from an oblique angle, θ, into rays 4 which are approximately normal to its surface. These reflected rays 4 are contained within a small angular spread if the period p of the wedge is much greater than the wavelength of the light, λ. It is essential that the wedge angle (θ/2) for the surface 3 in FIG. 1A, be selected for the particular application (e.g. ν/2=15°) and that the period p be large compared to the wavelength (typically p>100λ). However, a period that is too large (>100 microns for example) may be visually annoying. If p is not much larger than λ, then incident light is scattered over other angles than that normal to the surface, as predicted by diffraction analysis. Furthermore the angle of scattering is then wavelength dependent, a feature that tends to detract from a desirable white diffusion pattern.
Referring further to FIG. 1B, the diffuser further includes a second structure 5 , which is disposed on the reflective surface. The second structure uniformly reflects incident rays across a prescribed angle, α. The surface 6 , which is shown in FIG. 1C, accepts an incoming oblique beam and scatters it uniformly over a range of angles, α. The scattered beam is centered on the normal to the structure with high efficiency. The geometry of the second structure 5-or scattering structure, may itself be periodic with period q, which is smaller than, equal to, or slightly larger than the wedge period p. Such examples of these structures are shown in FIG. 2 .
There are a variety of surface shapes that may be used for these structures. In the present embodiment, a shape for an element of the resulting combined surface can be described by the simple equation:
s ( x )= ax 2 +bx, (1)
where s(x) is the height of the surface and x is the coordinate on the surface, and an element is defined to span only one peak of the structure as is shown by the dimension q in FIG. 2 . The second term of equation 1 represents the tilted flat surface on wedge 3 . The first term is that of a quadratic, or parabolic reflector, either positive or negative.
Simple microlens arrays may be approximated by periodic, two-dimensional parabolic surface arrays and as such have been used successfully to create flat top diffraction patterns, i.e., uniform on-axis reflection (or transmission) over a specific range of angles. Theoretically, a plane wave of incident light is uniformly reflected from a periodic surface throughout a specific range of angles because it has a constant second derivative.
In general, the diffraction from any reflective phase surface element, s(x), can include: f ( γ ) ≈ ( 1 / q ) ∫ - q / 2 q / 2 exp [ 2 i s ( x ) k ] exp [ - i k x γ ] x ( 2 )
where γ is the reflection angle (radians), and k=2π/λ. For example, inserting for s(x) the parabolic function of equation 1, minus the wedge (sawtooth) portion, equation 2 yields f ( γ ) ~ exp [ i k γ 2 / 8 a ] ∫ t 1 t 2 exp ( - i π t 2 / 2 ) t ( 3 )
where
t 1 =−{square root over (2 a/λ )}q+{square root over ({fraction ( 1/2)})} aλ γ
and
t 2 =+{square root over (2 a/λ )}q+{square root over ({fraction ( 1/2)})} aλ γ
The integral in equation 3 is known as the Fresnel integral.
A typical plot of the amplitudes of the diffraction function of equation 3, is shown as the dashed curve 7 of FIG. 3 . Such curves are derived by data plotted in cornu spirals, which are a convenient representation of these Fresnel integrals. As the size q of the element increases, the undulations evident at the extreme angles are reduced and the curve approaches the flat top distribution, which is desired for a preferred embodiment. However, this second component of the diffuser structure is periodic, the periodicity of which is q. For a periodic structure, the angular reflection distribution is punctuated by distinct peaks, the distance between which is proportional to the wavelength, λ, but is inversely proportional to the element size q. These peaks, which represent the various orders diffracted by the structure, are centered on the solid lines 10 shown in FIG. 3 . The presence of these periodic peaks need not be detrimental to the diffuser visibility if the period q is large compared to the wavelength, in which case they will be very close together, or if the incident light is specularly broad or spatially diffuse, thus obscuring them. For the examples in FIGS. 2A and 2B, the elements 11 and 12 are as large as that of the sawtooth, i.e., q=p, which is an extreme, and perhaps a desirable case, because it also reduces the undulations in the envelope (the dashed curve) as discussed before.
For parabolic structures, the diffraction function for elements 9 and 12 , shown in FIGS. 2B and 2D, is slightly different than that represented by equation 3 due to the inverted parabolic function. The applicable equation for that surface is f ′ ( γ ) ~ exp [ i k γ 2 / 8 a ] ∫ t 3 t 4 exp ( - i π t 2 / 2 ) t ( 4 )
where
t 3 =−{square root over (2 a/λ )}q+ {square root over ({fraction (1/2)})} aλ γ
and
t 4 =+{square root over (2 a/λ )}q+ {square root over ({fraction (1/2)})} aλ γ
The function f′ is the complex conjugate of f (i.e., f′=f*), a result that is evident from Fourier analysis, and so the amplitude of f′ is also represented by the dashed curve 7 of FIG. 3 . Here again, a periodic structure as shown in FIG. 2D, results in peaks represented by the solid lines 10 .
The structures 13 and 14 shown in FIGS. 2E and 2F combine the elements described by equation 3 and equation 4. After addition of suitable requisite phase terms (to account for lateral shifts and pedestal phase functions), these surface components, in the absence of the sawtooth component, give diffraction functions f(γ)
f (γ)˜ e{exp[ik γ/2+ i ka 2 /2 ]f (γ)} (5)
where the symbol e refers to the ‘real part’.
Because of the additional phase terms in equation 5, the dashed curve 10 of FIG. 3 represents the maximum diffraction that is achieved. Furthermore, peaks occur in this curve at half the distance of those for the cases discussed so far, since the period of this combined structure is now 2q versus q previously.
The surface shown in FIG. 2G is particularly interesting. Each element of FIG. 2A alternates with its inversion shown in FIG. 2B to produce a surface without discontinuities. Each element of width P, is an offset parabola when equation (1) is applied.
A surface which approximates the undulating parabolic surface of FIG. 2E (disregarding the sawtooth or wedge) is that which is represented by a sine or cosine function. Such a function can be constructed from the surface relief etching of two interfering, coherent beams. A function describing such a surface can include:
s ( x )≈ c sin(π x/q ) (6)
where 2c is the peak-to-peak excursion of the function, which is periodic in 2q. Inserting this function into equation 2 results in the diffraction function f ( γ ) ≈ ∫ - q q exp . [ 2 i k c sin ( π x / q ) ] exp . [ - i k x γ ] x ( 7 )
whose solution is
f (γ m )˜ J m (2 kc ) (8)
where J m is the m th order Bessel function of the first kind, m is an integer, and f(γ m ) represents the amplitude of the diffracted (or reflected) beams at the discrete angles of γ=mλ/p. In FIG. 4, discrete values of |f(γ m )| 2 , for example 15 and 17, are plotted for the case in which the period 2q equals 38λ, and the angular spread is approximately ±15 degrees. As can be seen in FIG. 4, the profile 16 is not flat-topped, but peaks at specific angles ( 17 in FIG. 4 ). Such peaks tend to be reduced as the period, 2q, increases with respect to the wavelength, and a reasonable approximation to a flat top angular distribution is obtained.
Another method of producing a parabolic surface structure holographically is by the coherent interference of three laser beams in a layer of photoresist. If the sources of expanded light from each of the beams are arranged such that each source is approximately at the apex of an equilateral triangle, then the developed pattern in the photoresist will consist of a close-packed honeycomb array. By using suitable nonlinear etching characteristics of the photoresist, each honeycomb depression will develop in the shape of a paraboloid.
While the specific examples discussed so far relate to the reflection of incident light from a surface in air (i.e., n=1), the analysis also applies to cases in which the light is reflected from a surface that is covered, for example, by a plastic overcoating. In an embodiment, a reflective diffuser is provided, which includes a reflective surface that is embossed into the underside of a plastic sheet. In this embodiment, slight modifications to the analysis must be made, mainly in an alteration of the depth of the structure. (In equation 2, for example, s(x) becomes n s(x), where n is the index of refraction of the plastic). Also certain modifications would enable these devices to be used as transmission diffusers, rather than reflection diffusers.
Construction of surfaces discussed herein, and examples of which are shown in FIG. 1, may be carried out by a number of processes. For well defined periodic functions like those shown in FIG. 1, the surfaces can be formed by micro-machining or laser etching (e.g., MEMS processes). Alternatively the surfaces can be formed in two separate steps, which includes a first step that produces a periodic sawtooth structure such as that shown in FIG. 1 A. Such a strictly periodic structure can, for example, be machined with great precision and cast into a number of materials. A second step, which adds the diffusion, or second component, may be added, for example in the following way. After appropriately coating the periodic sawtooth structure with a photoresist layer, the diffusing structure may be created by exposure to appropriate optical patterns and suitable processing of the photoresist thereafter. These optical patterns may be generated as an interference pattern of a number of coherent beams (the sine wave for example), the three-beam honeycomb pattern as described above, or as a result of scanning the photoresist surface with a focused intensity modulated light beam (as with a laser). Alternatively the optical pattern to which the photoresist is exposed may be a random function resulting, for example, from a laser illuminated diffuser. Randomly diffuse functions whose angular diffraction envelope are flat-topped, are usually difficult to create, unless unique processes are used.
The randomness may be achieved for example by using small portions of the prerequisite parabolic surface, which are randomly positioned but which on the aggregate cause reflected light to be more or less uniformly reflected over the desired angle.
Another process, described in the following, is a direct holographic method. The structure created by this method is different than that discussed so far, in that the period p is of the same order as the wavelength, λ, and thus diffraction effects become important. FIG. 5 illustrates the results of scalar diffraction theory, in which curve 18 is the major diffracted order, and the diffraction efficiency approaches 100% for the wavelength of interest. The step height h for the case shown in the FIG. 6 is equal to half the peak wavelength. For a central wavelength peak of 500 nm, the step height is thus 250 nm. This efficiency curve assumes that the surface is an ideal reflector, providing 100% efficiency at the peak wavelength. The efficiencies are also high for the entire visible spectral range, roughly ranging from approximately 85% at 400 nm in the violet to approximately 75% at 700 nm in the deep red. For this reason 500 nm is generally chosen to represent the center of the visible spectrum, and the surface structure is designed to operate at this wavelength. Note that there is a significant difference between the small scale structure represented by curve 18 , and the diffraction (or reflection) from the surface 3 of FIG. 1 A. In FIG. 1A, the step height is many wavelengths, resulting in a diffraction efficiency of close to 100% for all visible wavelengths.
The parameters of FIG. 5 are chosen for the case of an air interface bordering the reflective sawtooth surface, similar to the situation shown in FIG. 1 A. In the actual case, as with the situation of FIG. 1A, a preferable configuration is the coating of the surface with a protective layer, usually a clear plastic material 19 having an index of refraction, n=1.5, as in FIG. 6 . The tilt angle of the sawtooth 3 is chosen to provide an optimum viewing angle normal to the surface when light is incident at the proper offset angle, which for illustrative purposes can be 30 degrees. The wedge angle, β/2, can be selected for the overcoated surface as shown in FIG. 6 . Snell's Law, sin θ=n sin β, for light passing from air with index 1 into a medium with index n, yields, for an entrance angle from air of θ=30 degrees, an exit angle of β=19.47 degrees within the n=1.5 surface. The wedge tilt angle is half this value, or 19.47/2=9.74 degrees. The revised step height is h=250/n=250/1.5=166.67 nm. The period p is calculated from the grating equation for normal incidence, λ=p sin θ, or p=500/sin 30°=500/(1.5 sin 19.47°)=1000 nm=1.0 micron.
One method of creating the periodic wedge is by recording the interference of two counterpropagating laser beams, 20 and 21 in FIG. 7, in a material 22 such as photoresist (n=1.7). The equation for spacing between the interference planes, d, can include:
d =λ o /[2 n sin(θ o /2)](9)
where θ o is the half angle between the beams, and λ o is the laser recording wavelength. Thus the sine of the half angle is calculated in accordance with the following:
sin (θ o /2)=λ o /(2 nd )=441.6/[(2)(1.7)(169.11)=0.76803 (10)
where a recording wavelength of λ o =441.6 nm from a He—Cd laser and an index of refraction of n=1.7 for photoresist have been used. The spacing, d, has been calculated as
d=h /[cos(β/2)=166.67/[cos(9.74°)=169.11 nm (11)
Thus equation 10 yields an angle between the beams of θ o =100.360. The interference fringe structure, 23 , is shown in FIG. 7 . This structure represents, after exposure, planes of maxima and minima of exposure intensity. When the photoresist plate is immersed in developer, etching or removal of the exposed photoresist proceeds from the top surface layer downward, the most exposed layers being removed preferentially over the least exposed layers. Ideally, the developer reaches the first zero exposure plane, which is represented by the dotted line 24 in FIG. 7 . The fringe planes lying beneath this plane are not affected by the development.
The preceding discussion represents the types of calculations that must be made in order to accurately form the fringe planes, and thus the sawtooth structure in a photoresist material, which is ultimately used as a master copy for mass production. In an embodiment, at least one of the beams, 20 and 21 , in FIG. 7, can have some variation so as to create the desirable angular diffusion.
If there were no diffuse component to the beam, then the light diffracted from the sawtooth surface relief structure would, for incident white light, display all the spectral colors from violet to red, although each would be viewable from a different angle. But controlled diffusion is a requirement of this technology. Adding a diffuse component to obtain white light means adding a variation in the grating period p or in the slope of the sawtooth, so that all colors are mixed at the same diffraction angle. For example, taking the extremes of 400 nm for violet and 700 nm for red, the period p for these two colors is, respectively, p=400/sin 30°=800 nm (violet) and p=700/sin 30°=1400 nm (red) for the same diffraction angle of 30 degrees. If these extremes in the period for the visible spectrum are now present as part of the surface relief structure, then the diffraction angles for the design wavelength of 500 nm range from 38.68 degrees to 20.92 degrees, so that the total variation is 8.68+9.08=17.76 degrees. Since the diffuser is nominally designed to operate at an angular spread of plus or minus 15 degrees from the main diffraction angle of 30 degrees (or a total angular spread of 30 degrees), there is sufficient angular variation for mixing the entire visible spectrum sufficiently to produce white light.
A method for making the diffuse structure is to use a split beam holographic setup and a predetermined diffuse surface. This method allows for flexibility in the range of recording angles. The method does, however, require the fabrication of a diffuse plate with the requisite viewing angles, which is inserted into at least one of the two recording beams. In one configuration, as shown in FIG. 8, requires the use of two prisms, 25 and 26 , with a liquid gate plate holder contacted by index matching liquid to both prisms. The calculated angles for beam 20 with respect to the normal, i.e., 49.56 degrees, is so large that it exceeds the critical angle, θ c , which is θ c =arcsin (1/n)=arcsin (1/1.7)=36.03 degrees. In the absence of a coupling medium, i.e., an air interface, all incident light would be at almost normal incidence to the face of the equilateral prism 25 . Beam 20 enters the face of the opposite prism 26 such that the angle of incidence to the photoresist material 22 from the n=1.5 glass layer is equal to 34.61 degrees. In this case the fringe spacing and tilt angle in the photoresist are as required for the example above. Because the angle of incidence of beam 20 does not exceed the critical angle into photoresist, an alternative scheme allows beam 20 to enter the tank directly from air at 58.43 degrees, A third alternative is one in which the rectangular plate holder tank is immersed in a large square tank filled completely with index matching liquid, thus eliminating the prisms altogether. While this latter method is relatively easy to implement it does require great care in allowing the index matching liquid to completely stabilize before making the recording.
Copying directly from a volume diffuser, as an alternative to the above, has many advantages. One advantage relates to a volume diffuser with the requisite offset and viewing angles, which can be efficiently produced holographically. Another advantage relates to the copying procedure, which is simpler than direct recording using a predetermined diffuse master, provided certain conditions are met. One of these conditions is that the peak wavelength of light diffracted from the master falls roughly into the center of the visible spectral range. Also the volume diffuser, which is used for copying, can have the proper angular spread to create an adequate viewing angle in the reflective mode.
A method of forming a structure like that of FIG. 7 from a volume hologram is shown in FIG. 9 . In order to form such a structure we assume that (1) photoresist 22 , is in intimate contact with the holographic diffuser 27 , (2) beam 21 is incident from outside, passing through the photoresist and into the volume hologram, (3) beam 20 is reflected from the interference planes 28 within the volume hologram back through the photoresist layer and (4) the index of refraction of the volume hologram has a typical value of n=1.5. Thus copying is done with only a single beam.
In order to create beams 20 and 21 at angles of 49.56 degrees and 30.08 degrees (as shown in FIG. 7 ), these beams, denoted as 29 and 30 in FIG. 9, must have angles of 59.61 degrees and 34.61 degrees respectively in the lower index material 27 (n=1.5). Such beams exist in the volume reflective hologram 27 only if it contains fringe planes tilted at 12.5 degrees as shown in FIG. 9, and whose spacing d=216.28 nm. This assumes that the copy wavelength is 441.6 nm. Light incident normally onto these fringe planes will reconstruct coherently at a wavelength of λ=2nh=2(1.5)(216.28)=648.85 nm, which is red. This result points out a fundamental characteristic of this type of construction; namely, that copying into a high index material at large incidence angles from a lower index master, requires that the master be red-shifted with respect to the copy. In other words, reconstruction of a blazed surface pattern producing light peaked in the green spectral region requires a master peaked in the red spectral region. Such a volume hologram can be easily made with a conventional holographic setup using red laser light (e.g., a Kr laser at 647 nm or a He—Ne laser at 633 nm) and either red-sensitive photographic emulsion or photopolymer. It is also possible to copy from a photopolymer master diffuser that is already tuned to the green spectral region, provided that certain steps are made to convert the diffuser to the red region. For example, the green Polaroid Imagix diffuser photopolymer can be copied directly into a DuPont 706 photopolymer, using either green laser light at near normal incidence or blue 441.6 nm laser light at a large angle of incidence. The DuPont material can then be tuned to the red region using DuPont CTF color tuning film, which essentially swells the photopolymer to a larger thickness, thereby increasing the spacing between the planes and changing the color from green to red.
Here again the angle for beam 20 in the photoresist is greater than the critical angle (49.56>36.03) and we must resort to coupling by means of a liquid gate. The photoresist plate is placed in a rectangular tank containing an index matching liquid for glass at n≈1.5 (e.g., xylene) that is liquid coupled to an equilateral prism, as shown in FIG. 9 .
Variations of the methods disclosed here can result in efficient directional diffusers. For example, with the first type disclosed, uniform angular spreading of the incident beam may be accomplished by a variation of either the period p or the slope θ/2 from sawtooth element to sawtooth element. However, such a procedure may require that the element size p be reduced (for example from 100λ to 10 or 20λ) so as to preserve the smooth visual texture of the diffuser. If the size p is too large, visible portions of the diffuser will not scatter into the observation direction.
A variation of the holographic method discussed herein, is the addition of a fine diffusing structure to a coarse wedge structure. This coarse wedge structure is of larger dimensions than that of the methods described in FIGS. 7 and 8, and can be constructed in the following manner, as shown in FIG. 10 . Two beams enter the photoresist layer 33 that is coated onto a glass substrate 34 from the same side 35 at an oblique angle, such that the interference fringe structure 36 is coarse and inclined at some angle with respect to the surface. Prism coupling allows for a large degree of obliquity in a manner similar to that shown in FIG. 9 .
A diffuse component can be added in a second exposure step by contacting the photoresist layer 33 to a reflective diffuser 39 , as shown in FIG. 11 . In this case the incident beam 37 is totally reflected as a diffuse beam 40 that encompasses a range of angles. The contact can be done using either a liquid gate, or by reversing the plate and attaching the diffuser directly to the glass substrate and using a liquid gate between the photoresist and the prism. For this procedure to be effective, the resist should be coated to a several micron thick layer. The first exposure should be done at a laser wavelength for which absorption is large, for example 441.6 nm, so that the amount of reflected light is minimal. The second exposure should be done at a longer, less absorbing wavelength, for example 457.9 or 476 nm, so that the reflected beam is nearly equal in intensity to the incident beam.
An alternate technique adds a fine step structure to the coarse wedge of FIG. 10, in place of the fine diffusing structure. With this technique the second exposure uses two beams that enter the photoresist from opposite sides so that the interference fringe structure is fine and parallel to the surface. This is also done by prism coupling, using a single beam 37 that is totally reflected that interferes with itself, as shown in FIG. 12, with the fine fringe structure designated as 38 . For this exposure the photoresist plate is reversed so that the surface 35 faces out. When the photoresist is developed after the composite exposure, the resulting structure is a deep wedge-shaped grating that has a fine stepped grating superimposed onto it (FIG. 13 ).
The diffraction efficiency for a ten-level structure is shown in FIG. 14 and includes the spectral distribution for diffracted orders +2, +1, 0, −1, and −2. Also included in this plot is the spectral distribution for a single-step blazed grating, which is identical to FIG. 5 . It is clearly evident that the spectral distribution for the single-step shallow blazed grating forms an envelope for the ten-level deep stepped grating. The number of orders that appear under this envelope decreases as the number of levels is reduced, but their individual spectral width increases.
As can be seen from FIG. 14, the diffraction is specularly discrete, allowing only narrow band color components to be observed at any given viewing angle. In order to avoid this often undesirable result, the photoresist can be exposed in narrow adjacent stripes that yield, for example, red, blue, and green light diffracted at the same angle to produce white. The proper angle for light diffracted from the stepped grating structure is determined by the periodicity of the coarse wedge grating, and that periodicity depends, in turn, on the oblique angle that the interference fringe structure makes with respect to the photoresist surface.
Another variation on this method consists of first making a wedge grating structure of large periodicity and adding the step structure or diffuse structure to it holographically. In this configuration, it is similar to the structure shown in FIG. 1 c . For the step structure, the procedure consists of coating the wedge structure with a thin, uniform layer of photoresist, which can be done either by dip coating or by spin coating. The coated wedge surface is then immersed in an index-matching liquid gate that is optically contacted to an equilateral glass prism, as described above. The step structure is made by exposing to a totally reflecting beam of laser light that is coupled to a diffuse surface, also described above. With this method many more diffracted orders are obtained than with the totally holographic method described above, due to the much greater depth of the preformed structure compared to that obtained holographically, but with diffuse mixing the diffracted light appears white.
The discussion has focused on devices that uniformly scatter light through a solid angle. But in some applications it may be desirable to achieve non-uniform scattering. One can modify the processes to create blazed diffusers that have a wide range of scattering properties.
Both categories of structures have been described in the foregoing in reference to their scattering properties in one dimension only. That is, the emphasis has been on showing how an incident beam whose obliquity to the surface (i.e., θ=30°) is scattered uniformly throughout an angle α, as in FIG. 1 . But in the other direction, which follows the coordinate going into the paper in all of the Figs., the illumination beam 2 (See FIG. 1) is assumed to have no obliquity, but to impinge perpendicular to the surface. In order to obtain a uniform angular diffusion, there is a similar requirement for scattering over an angle of α in this dimension also, albeit without an offset θ. For the first category of diffuser described here, the surface profile into the paper for the surface of FIG. 2 would contain the parabolic component, thus providing a diffuser, each portion of which scatters uniformly throughout a pyramidal solid angle which is offset from the incident illumination by angle θ. Similarly if a beam, which is randomly diffuse throughout a cone of angles, is reconstructed as beam 20 in FIG. 9 from the photopolymer hologram 27 , the resulting aluminized diffuser will scatter incoming light throughout a conical solid angle, offset by angle θ
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 is not intended as limiting. | A diffuser is disclosed which transmits or reflects incident light into a specific range of angles. In a preferred embodiment, this light is uniformly scattered throughout a cone of angles. The diffuser consists of two parts. The first part diffracts or reflects light into a specific offset angle. The second part, in the preferred embodiment, uniformly scatters the light through a range of angles, which is centered on the offset angle. The diffusers have utility in applications such as screens for wrist watches, computers, calculators, and cell phones. | 8 |
CROSS REFERENCE TO RELATED APPLICATIONS
This is a continuation of co-pending International Application No. PCT/EP98/00791, filed Feb. 12, 1998.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an electronic ballast for operating at least one gas discharge lamp wherein the gas discharge lamp is supplied with an alternating voltage and wherein the lamp filaments are preheated.
2. Description of the Related Art
Such a ballast is known from EP-A1-0 490 329.
As in the case of other lamps as well, in the case of gas discharge lamps on account of the phenomena of wear of the heater filaments at the end of the life of the gas discharge lamp the effect that occurs is one where the lamp electrodes wear unevenly over time, that is, the erosion of the emitting layers on the lamp electrodes is different. On account of the differing wear of the lamp electrodes, differences result in the emitting power of the two lamp electrodes.
FIG. 5 shows the consequences of this effect with reference to the current i L that is fed to the gas discharge lamp. It can be seen from FIG. 5 that a higher current flows in the one direction than in the other so that the time characteristic i L (t) has an excess of one half-wave (in FIG. 5 the positive half-wave) . As a result of the different erosion of the two lamp electrodes, asymmetries thus result that not only give rise to comparatively great light-flickering at the end of the life of the gas discharge lamp, but even in the extreme case also only permit operation of the gas discharge lamp during one half-wave (in FIG. 5 during the positive half-wave). In this case, the gas discharge lamp acts as a rectifier so that the previously described effect is termed a "rectification effect".
The work function for the electrons is higher at that electrode which has worn away to a greater extent in the course of time than at the other electrode which has worn away to a lesser extent. The minimum energy required to draw an electron out of a metal, in the present case out of the lamp electrode, is generally termed the work function. The dipole layer at the surface of the metal, that is, the lamp electrode, is then an important factor in determining the work function. The electrode that has worn away to a greater extent and which has a higher work function for the electrons than the electrode which has worn away to a lesser extent consequently heats up to a greater extent when the gas discharge lamp is put into operation than the opposing electrode. The increase in temperature in the electrode can be so great, in particular in the case of lamps with a small diameter, that portions of the glass lamp bulb can melt. In order to avoid the risk of an accident resulting from the increase in temperature of the glass lamp bulb, consequently it is necessary to identify the rectification effect and, if applicable, switch off the gas discharge lamp or reduce its power input, in which case there are already mandatory standards for monitoring the previously described uneven emission of the lamp electrodes.
As has already been mentioned above, the rectification effect manifests itself in asymmetry of the lamp current i L flowing by way of the gas discharge path of the lamp. one possibility for identifying the rectification effect is therefore to monitor the lamp current flowing by way of the gas discharge path of the lamp, in which case with this method it is certainly possible to identify differences in emission of the lamp electrodes directly, but the evaluation of these emission differences and also the translation of this identification process into a monitoring circuit arrangement that is designed as an integrated circuit, in particular as an application specific circuit (ASIC), are problematic. As an alternative to this, it is also possible to identify the rectification effect by monitoring the lamp voltage, since the asymmetries occurring in the lamp current are transferred to the lamp voltage. If, for example, the monitored lamp voltage exceeds a specific limiting value in one direction as a consequence of the asymmetrical emission of the lamp electrodes, the gas discharge lamp is switched off. In the case of this identification process, however, it is disadvantageous that the sensitivity of this method is limited, since in the case of a fault, that is, if the rectification effect occurs, the peak value of the lamp voltage that is detected is merely 60% higher than its value in the normal operating case. Moreover, even when the gas discharge lamp is dimmed, the lamp voltage is changed so that on account of the dimming of the gas discharge lamp and on account of the lamp voltage that rises in a corresponding manner as a result, it may possibly be concluded by mistake that the rectification effect is present in the gas discharge lamp. Furthermore, it would be desirable to use the changing arithmetical mean value of the monitored circuit variable for the detection of the rectification effect. This is not a possibility, however, when monitoring the lamp voltage, since--as already described--in the case of a fault the peak value of the lamp voltage is merely increased by 60% so that the increase in the mean value of the lamp voltage is not sufficient to detect the rectification effect in a sufficiently precise manner. All in all, therefore, the detection of the rectification effect by monitoring the lamp voltage is problematic.
In the case of the electronic ballast known from EP-A1-0 490 329 belonging to the applicant, a first resistor is connected in series with the primary winding of the filament-heating transformer. The current flowing through the primary winding and the first resistor generates a voltage at the resistor, which voltage is proportional to the current flowing through the heater filaments of the lamp. The voltage drop across the first resistor is evaluated by a control and regulating circuit arrangement in order to detect overvoltage or undervoltage. Identification of a rectification effect is not, however, described in this publication.
Identification of a rectification effect is, however, described in U.S. Pat. No. 5,023,516. For this purpose, a monitoring circuit arrangement is provided that comprises a series circuit arrangement consisting of two resistors and an inductor, with the series circuit arrangement being connected in parallel with a gas discharge lamp that is to be monitored. A thyristor, which is coupled to the inverter of the ballast, acts at the interconnection point between the one resistor and the inductor and thus evaluates the voltage dropping across the one resistor for the purpose of identifying the rectification effect. As soon as the voltage, which drops across the one resistor and which is proportional to the current flowing by way of the one resistor, has reached a specific limiting value, the thyristor is activated and consequently the inverter is switched off. The known monitoring circuit arrangement, however, only detects the presence of a rectification effect in one direction of polarity of the voltage dropping across the resistor.
SUMMARY OF THE INVENTION
The underlying object of the invention is to provide the known electronic ballast with a monitoring circuit arrangement with which the rectification effect can be detected in a more precise manner.
This object is achieved in accordance with the invention by means of an electronic ballast for operating at least one gas discharge lamp. The ballast includes an inverter having a load circuit which is connected to the inverter and to which a gas discharge lamp can be connected. The electronic ballast also includes a filament-heating transformer for preheating the lamp filaments of the gas discharge lamp. The primary winding of the transformer is connected in series with a first resistor in parallel with the gas discharge lamp. A monitoring circuit arrangement is provided for monitoring current flowing by way of the primary winding of the filament-heating transformer or a variable that is proportionally dependent upon such current. The interconnection point between the primary winding of the filament-heating transformer and the first resistor is connected to the monitoring circuit arrangement by way of a second resistor so that the voltage drop across the first resistor and the current which flows by way of the second resistor are fed as monitoring variables to the monitoring circuit arrangement. The monitoring circuit arrangement assesses, as a monitoring variable, the presence of the rectification effect in the gas discharge lamp in the case of a voltage drop across the first resistor which increases in a positive direction or a current flowing through the first resistor which increases in a positive direction as a function of the voltage drop across the first resistor, in that the monitoring circuit arrangement assesses, as a monitoring variable, the presence of the rectification effect in the gas discharge lamp in the case of a voltage drop across the first resistor which increases in a negative direction or a current flow through the first resistor which increases in a negative direction as a function of the current flow through the second resistor, and in that the monitoring circuit arrangement is constructed to respond to the presence of a rectification effect in the gas discharge lamp upon the monitoring variable exceeding a predetermined limiting value.
The solution in accordance with the invention thus guarantees that the rectification effect is detected in both directions of polarization of the voltage dropping across the first resistor and as a result with a high level of sensitivity.
The circuit arrangement in accordance with the present invention can be extended in a simple manner in that devices with two or more flames can be reliably monitored for the occurrence of a rectification effect in one of the gas discharge lamps.
The filament or heating current or the variable that is proportional to the heating current flowing by way of the primary winding of the filament-heating transformer is monitored in particular with the aid of a monitoring circuit arrangement which is of such a kind that, after identification of the rectification effect, it activates the inverter supplying the gas discharge lamp with an alternating voltage in order to change the frequency and/or the pulse duty factor of the alternating voltage delivered by the inverter and thus to reduce the power consumed by the gas discharge lamp. In this way, the glass bulb of the gas discharge lamp is reliably prevented from melting after the occurrence of the rectification effect.
Other advantageous and novel features of the invention are described and claimed herein.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is described in greater detail in the following with the aid of preferred exemplary embodiments and with reference to the enclosed drawing, in which:
FIG. 1 shows a first exemplary embodiment of the electronic ballast in accordance with the invention for operating a gas discharge lamp;
FIG. 2 shows voltage and current characteristics in the case of a heating current that increases in a positive direction in the circuit arrangement that is shown in FIG. 1;
FIG. 3 shows voltage and current characteristics in the case of a heating current that increases in a negative direction in the circuit arrangement that is shown in FIG. 1;
FIG. 4 shows a second exemplary embodiment of the electronic ballast in accordance with the invention; and
FIG. 5 shows the characteristic of the lamp current over the gas discharge path of a gas discharge lamp when the rectification effect occurs.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows a first exemplary embodiment of the electronic ballast in accordance with the invention for operating a gas discharge lamp, wherein the inductor which is monitored and connected in parallel with the gas discharge lamp is formed by the primary winding of a filament-heating transformer. The solution in accordance with the invention generally consists in evaluating the current flowing by way of an inductor connected in parallel with the gas discharge lamp or a variable that is proportional thereto, since the asymmetries that occur in the lamp branch in the case of a rectification effect are transferred to the current flowing by way of this inductor.
The electronic ballast shown in FIG. 1 in the main has a rectifier circuit arrangement 1, an inverter 2, a monitoring circuit arrangement 3 and also a load circuit connected to the inverter 2 which inter alia contains a gas discharge lamp 10 which is to be operated and monitored for the occurrence of the rectification effect. The rectifier 1 is connected to a mains voltage source and converts the mains voltage into a rectified intermediate voltage which is fed to the inverter 2. The inverter 2 as a rule comprises two controllable switches (not shown), for example MOS-field effect transistors, which are alternately activated by means of a corresponding control circuit arrangement so that in each case one of the switches is switched on and the other is switched off. The two inverter switches are connected in a series circuit arrangement between a supply voltage and earth, in which case the load circuit containing the gas discharge lamp 10 is connected to the common junction between the two inverter switches. In addition to the gas discharge lamp 10, the load circuit comprises a series-resonant circuit with a resonant circuit coil 4 and a resonant circuit capacitor 5 which is connected to earth. Connected to the interconnection point between the resonant circuit capacitor 5 and the resonant circuit coil 4 there is a coupling capacitor 6 which is connected to one of the lamp filaments of the gas discharge lamp 10. On account of the fact that the switches of the inverter 2 are activated alternately, the rectified intermediate voltage is converted into a "chopped" high-frequency alternating voltage. This high-frequency alternating voltage is fed to the gas discharge lamp 10 by way of the series-resonant circuit.
Before the firing voltage is applied to the gas discharge lamp 10, the lamp electrodes of the gas discharge lamp 10 are preheated in order to extend the life of the gas discharge lamp. A filament-heating transformer having a primary winding 7A and two secondary windings 7B and 7C is provided for the purpose of preheating the gas discharge lamp 10. The primary winding is connected to the series resonant circuit, whilst the secondary windings are, in each case, connected in parallel with one of the lamp filaments. In this way it is possible to supply the lamp filaments with energy in the fired mode of operation as well. During the preheating operation, the frequency of the alternating voltage delivered by the inverter 2 is changed in relation to the resonant frequency of the series-resonant circuit in such a way that the voltage across the resonant-circuit capacitor 5 and thus across the gas discharge lamp 10 does not cause the gas discharge lamp 10 to be fired. In this case, a substantially constant current flows through the lamp electrodes of the gas discharge lamp 10 that are realized as filaments, whereby the lamp filaments are preheated. At the end of the preheating phase, the frequency of the alternating voltage delivered by the inverter 2 is shifted into the proximity of the resonant frequency of the series-resonant circuit, whereby the voltage applied to the resonant-circuit capacitor 5 and the gas discharge lamp 10 is increased so that the gas discharge lamp 10 is fired.
In accordance with the invention it is proposed that the primary current i 1 flowing by way of the primary winding 7A of the filament-heating transformer be monitored. To this end, connected in series with the primary winding 7A there is a resistor 9 which is connected to earth. A further resistor 8 leads from the interconnection point between the primary winding 7A and the resistor 9 to the monitoring circuit arrangement 3 which for its part is connected to earth. The function of the electronic ballast in accordance with the invention, as shown in FIG. 1, is described in greater detail in the following with reference to FIG. 2 and FIG. 3.
As shown in FIG. 5, when the rectification effect described at the beginning occurs, asymmetries result in the lamp current i L that flows by way of the gas discharge path of the gas discharge lamp 10. As soon as this asymmetrical current i L occurs in the lamp branch, the asymmetries are transferred to the primary current i 1 flowing by way of the primary winding 7A of the filament-heating transformer. In order to be able to detect and evaluate the asymmetries that occur in the primary current i 1 , the primary current i 1 is fed by way of the resistor 9 to the monitoring circuit arrangement 3. In this connection, a distinction is to be made between two different cases, depending on whether the half-waves of the lamp current i L shown in FIG. 5 relate to the positive or negative half-waves. In other words, in accordance with the invention a distinction is made between the rectification effect that occurs in the one direction of the gas discharge lamp 10 and the rectification effect that occurs in the opposite direction.
For the case where on account of the rectification effect that occurs in the gas discharge lamp 10 a current i 3 that changes in a positive direction flows by way of the resistor 9, in accordance with the invention the rectification effect is detected by monitoring the voltage u 3 that drops across the resistor 9. FIG. 2a show the time characteristic of the voltage u 3 that drops across the resistor 9 in this case. On account of the different wear of the lamp electrodes that occurs as a result of the ageing of the lamp electrodes, in the course of time, as already described at the beginning, an excess of the positive half-waves in relation to the negative half-waves results in the voltage u 3 that drops across the resistor 9 or in the current i 3 flowing by way of the resistor 9 respectively. In the extreme case, over time the negative half-waves in the voltage and current characteristics of u 3 and i 3 respectively completely disappear so that the gas discharge lamp 10 acts as a rectifier. A threshold value U S can be defined by way of the resistance value of the resistor 9 and when this threshold value U S is exceeded the presence of the rectification effect is identified. In order to monitor the voltage u 3 dropping across the resistor 9, the monitoring circuit arrangement 3 is also connected to earth so that the monitoring point A of the monitoring circuit arrangement 3 cannot accept a potential that is more negative than the earth potential. FIG. 2b shows the characteristic of the potential u 4 that occurs at the monitoring point A. Since the potential u 4 cannot assume a more negative value than the earth potential, the voltage characteristic of u 4 only has positive half-waves that correspond to the positive half-waves of u 3 . If one of these half-waves exceeds the predefined threshold value U S , the monitoring circuit arrangement 3 interprets this as the occurrence of the rectification effect in the gas discharge lamp 10. FIG. 2c in a supplementary manner shows the current characteristic of the current i 2 flowing by way of the additional resistor 8. It can be seen from FIG. 2c that the current i 2 only occurs when the voltage u 4 applied at the monitoring point A is zero.
FIG. 3 shows the corresponding voltage and current characteristics for the case where the previously described rectification effect in the gas discharge lamp 10 occurs in the opposite direction to the case described with respect to FIG. 2. In this case, the current i 3 flowing by way of the resistor 9 or the voltage u 3 dropping across the resistor 9 assume values which rise in a negative direction so that the negative half-waves are excessive in respect of the positive half-waves in the voltage characteristic and current characteristic of u 3 and i 3 respectively. In the extreme case in the course of time the positive half-waves disappear completely so that the gas discharge lamp 10 acts as a rectifier in the opposite direction to the direction described with reference to FIG. 2. In the same way as FIG. 2b, FIG. 3b also shows that the potential u 4 that occurs at the monitoring point A on account of the connection of the monitoring circuit arrangement 3 to earth can only assume positive values so that over time with the disappearance of the positive half-waves of the voltage u 3 dropping across the resistor 9 the voltage u 4 assumes the value zero. In order, nevertheless, to be able to identify the presence of the rectification effect in the gas discharge lamp 10 in this case, in accordance with the invention it is proposed that the current i 2 flowing by way of the resistor 8 be evaluated in this case. The current i 2 can only flow by way of the resistor 8 if the voltage u 4 that occurs at the monitoring point A assumes the value zero. For this reason, from the time at which the voltage u 4 completely disappears, the current i 2 can be monitored continuously by the monitoring circuit arrangement 3. The characteristic of the current i 2 is then changed in line with the half-waves of the voltage u 3 rising in the negative direction.
For this reason, the rectification effect acting in the other direction of the gas discharge lamp 10 can be identified by monitoring the current i 2 flowing by way of the resistor 8, if this current i 2 exceeds a predetermined limiting value I S . This limiting value I S can be varied in particular by way of the value of the resistor 8. On the basis of the negative current values of the current i 2 represented in FIG. 3c, it can be seen in conjunction with FIG. 1 that the current i 2 flowing out from the monitoring circuit arrangement 3 by way of the monitoring point A is actually detected by the monitoring circuit arrangement 3. By simultaneously monitoring u 3 and also i 2 , the monitoring circuit arrangement 3 can thus reliably identify the rectification effect--irrespective of the direction in which the rectification effect occurs in the gas discharge lamp 10.
The monitoring of i 2 and u 3 in order to determine whether the limiting value I S or U S respectively has been exceeded is advantageously effected by means of standard current and voltage comparators.
As soon as the monitoring circuit arrangement 3 has identified that the voltage u 4 applied at the monitoring point A has exceeded the predetermined limiting value U S or the current i 2 flowing by way of the monitoring point A has exceeded the predetermined limiting value I S , the monitoring circuit arrangement 3 concludes that the rectification effect is present in the gas discharge lamp 10 and gives out a corresponding warning. The monitoring circuit arrangement 3 is advantageously connected to the inverter 2 and controls the operational performance of the inverter 2 after identification of a rectification effect in the gas discharge lamp 10 in such a way that the power consumed by the gas discharge lamp 10 is reduced. In particular, the monitoring circuit arrangement 3 controls the switching performance of the alternately switching switches of the inverter 2 in such a way that, for example, the frequency f of the switched-mode alternating voltage delivered by the inverter 2 is increased and/or the pulse duty factor d (that is, the relationship between the switch-on times of the two activated switches of the inverter 2) of the switched-mode alternating voltage is reduced so that the lamp current i L supplied to the gas discharge lamp 10 is reduced. In this way, excessive heating or melting of portions of the glass lamp bulb is reliably prevented. If applicable, the monitoring circuit arrangement 3 can also cause the inverter 2 to be switched off.
FIG. 4 shows a second exemplary embodiment of the electronic ballast in accordance with the invention, with a two-lamp load circuit being represented in the figure. The second lamp circuit is connected up in a manner analogous to the first lamp circuit. The second lamp circuit likewise comprises a filament-heating transformer, the primary winding 11A of which is connected to the series-resonant circuit and the two secondary windings 11B and 11C of which are connected to the lamp filaments of a second gas discharge lamp 15. Connected in series with the primary winding 11A of the second filament-heating transformer there is a resistor 13, which is additionally connected to earth. A connection leads from the interconnection point between the primary winding 11A of the second filament-heating transformer and the resistor 13 to the monitoring circuit arrangement 3 by way of a resistor 12. The monitoring circuit arrangement 3 has an OR-circuit arrangement 14, the inputs of which are connected to the monitoring points A and B and also to the resistors 8 and 12. Each of the monitoring points A and B is, as explained with reference to FIGS. 2 and 3, monitored for the occurrence of a rectification effect in the gas discharge lamp 10 and 15 respectively. The OR-circuit arrangement 14 signals the presence of a rectification effect as soon as it is possible to identify the rectification effect in one of the two gas discharge lamps 10 and 15 by monitoring the monitoring points A and B. As in the case of the exemplary embodiment shown in FIG. 1, in accordance with FIG. 4 as well after a rectification effect has been identified the inverter 2 is activated in a corresponding manner in order to reduce the power consumed by the gas discharge lamps 10 and 15 connected to the inverter 2.
The monitoring circuit arrangement 3 is advantageously designed as an ASIC (Application Specific Integrated Circuit).
On account of the proposed manner, in accordance with the invention, of monitoring the heating current which flows by way of the primary windings 7A and 11A of the corresponding filament-heating transformers and the characteristic of which changes greatly when a rectification effect is present in the corresponding gas discharge lamp 10 and 15 respectively, it is possible to identify the rectification effect in the gas discharge lamp 10 and 15 with great precision and in a reliable manner. The circuit arrangement proposed in accordance with the invention can easily be extended by means of simple measures in terms of circuit engineering in order to monitor two or more gas discharge lamps. | Method for detecting the rectification effect in at least one gas discharge lamp (10) and electronic ballast for operating at least one gas discharge lamp, which recognises the appearance of the rectification effect in the gas discharge lamp (10). In order to be able to detect the appearance of the rectification effect in the gas discharge lamp (10) simply and with high sensitivity there is monitored the current (i 1 ) flowing via a primary winding (7A), connected parallel to the gas discharge lamp (10), of a heating transformer (7A-C) or a parameter (i 2 , u 3 ) dependent upon this current (i 1 ) , and in the event that a predetermined limit value is overshot the presence of the rectification effect in the gas discharge lamp (10) is determined. | 8 |
CROSS REFERENCE OF RELATED APPLICATIONS
[0001] Pursuant to 35 U.S.C. 119, the benefit of priority from provisional Application No. 61/063,833 with filing date Feb. 7, 2008 is claimed for this Non-Provisional Application.
TECHNICAL FIELD OF THE INVENTION
[0002] The present invention relates generally to a shock resistant shoe.
BACKGROUND AND OBJECTIVES OF THE INVENTION
[0003] Shoes that contain mechanical springs or other contrivances in a prescribed volume between the foot and the surfaces on which a person is walking or running are known to develop functional problems that results in their nonuse or failure of the devices inserted in the sole to increase comfort, reduce fatigue or increase the athlete performance of the wearer. There are shoes with contrivances in the midsole that provide for cushioning of the foot against shock during a foot strike. This shock reduction can be achieved by various design and engineering techniques. Typically, inventors make use of a multiplicity of metal small diameter wave springs or cone springs. It is a primary objective of this invention to provide a shoe that uses large diameter metal cone springs in the midsole mounted in a manner such that the large diameter terminal end of the spring is proximate the board last. A second objective is provide integral wrist pin throughhole on mount discs in the out sole that allows for viewing of the spring from without while simultaneously providing a lower bearing surface for each in contact therewith. A still further objective is to provide shoe with an insole with stiffness greater than the spring rate of the selected springs such that the insole will not deform against the foot while bearing against the springs. Other objectives will become obvious during the course of the detailed description of the shoe of this invention.
BRIEF DESCRIPTION OF THE FIGURES
[0004] 1) FIG. 1 shows a side view of the first embodiment of the midsole with a cone spring mounted in a disc in the midsole.
[0005] 2) FIG. 1 a gives a sectional view of a Strobel last that can be used to replace the board last of FIG. 1 .
[0006] 3) FIG. 2 presents a side view of the cone springs of the first embodiment of this invention with small terminal end terminated wrist pin like.
[0007] 4) FIG. 3 presents a side view of the disc of FIG. 1 having an eyelet for accepting the noncircular wrist pin-like small terminal end of the cone spring of FIG. 2 .
[0008] 5) FIG. 4 presents a top view of a second embodiment with a single cone spring in the heel and two cone springs in the forefoot.
[0009] 6) FIG. 5 shows a cone spring with its circular small terminal end rigidly mounted on a disc for use in the ball and heel area of a third embodiment of the shoe of this invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0010] The present invention will be described below with reference to the accompanying figures.
[0011] Referring to the drawings of FIG. 1 a shoe in accordance with the present invention comprises: midsole assembly 2 ; an outsole 12 ; and, an upper 10 . The midsole assembly 2 comprises volumes 3 a and 3 b which are isolated from each other by divider 7 cooperating board last 6 ; mechanical springs 8 and 9 located within the separate internal volumes 3 a and 3 b of the midsole assembly 2 ; and, transparent discs 15 and 16 which are connected pivotally to the small terminal ends 8 a and 9 a of springs 8 and 9 .
[0012] The divider 7 which extends continuously from surface 3 c of the bottom interior of midsole assembly 2 up to the board last 6 where it is sealed therein to prevent the flow of fluid between volumes 3 a and 3 b. In this invention, the divider 7 is made of the same material as the midsole EVA (i.e., ethylene-venal-acetate). The divider could be made of extremely flexible material such that no flow of fluid occurs from volume 3 a to 3 b. That is, the divider may be allowed to grow toward the ball of the foot region of the shoe in response to pressure applied to the board last in the heel region during a foot strike. Likewise it would be allowed to expand in a rearward direction when volume 3 b is pressurized. Further, portions of board last 6 above volumes 3 a and 3 b contain a multiplicity of through slits 5 . The slits 5 allow air to resistively escape toward the volume commonly occupied by the sock liner of the shoe from volumes 3 a and 3 b during the natural movement of the feet during walking or running. In FIG. 1 outsole 12 is mechanically attached to midsole surface 3 d by ordinary adhesive 14 which is not shown in FIG. 1 . In the first embodiment of the shoe of this invention, the outsole 12 is composed of abrasive resistant polymeric material. The outer surface 3 d of midsole assembly 2 to which outsole 12 is adhesively attached via of adhesive 14 combine via mating through holes 22 a and 22 b in the bottom surface 3 d of midsole assembly 2 and outsole 12 , respectively, to mountingly accept transparent discs 15 and 16 which extends essentially through surface 3 d and outsole 12 . Throughhole 22 b in outsole 12 are countersunk to allow line-of-site viewing of the discs but prevent full penetration of throughhole 22 b when the discs are inserted therein. That portion of the first surfaces 15 c and 16 c of discs 15 and 16 that are in contact with the countersunk portions of throughhole 22 b is attached thereto by adhesive 14 (not shown in FIG. 1 ). The cylindrical surfaces of discs 15 and 16 are also attached to the cylindrical surfaces of throughhole 22 a by adhesive 14 (not shown in FIG. 1 ).
[0013] Discs 15 and 16 are attached to the shaped wrist pin like ends 8 a and 9 a of springs 8 and 9 , respectively, via eyelets 17 a and 18 a in male protrusion integrally attached to discs 15 and 16 . In this invention, the discs 15 and 16 are made of transparent plastics. They could, however, be made of opaque polymeric material. Also, while the discs 15 and 16 have protruding elements eyelets designed to accept the wrist pin like terminal ends of the cone springs of this invention, they could be designed with a groove in a prism integrally connected to the discs to accept the full length of the wrist like ends of the cone springs with rotational snap certainty. The adhesive 14 , when cured, has tear strength greater than 200 lbf and is designed to be resistant to corrosion by liquids commonly encountered in the workplace and during exercise or play. The thickness of Outsole 12 was selected such that it does not restrict the flextive motion of the outer sole required for comfort during the normal rolling motion of a shoe during walking and running. In the invention shown in FIG. 1 , the discs 15 and 16 are viewable from the bottom of the outsole 12 . The outsole could be assembled with an outsole that does not have the through holes of FIG. 1 .
[0014] In FIG. 1 , the side walls of the midsole on the medial and lateral are design such that they do not affect the natural function of the springs. The springs 8 and 9 are held rotatably firm at their small shaped ends 8 a and 9 a in wrist pin eyelets 17 a and 18 a, respectively, by ordinary pin fasteners not shown in FIG. 1 . The motion about the central axis 13 of throughhole 17 a and 18 a is such that the forward rolling motion of a foot strike is not impeded. With the shaped small ends 8 a and 9 a of springs 8 and 9 inserted in the throughhole 17 a and 18 a, the springs are restricted in the lateral to medial directions. Returning to FIG. 1 , the broad last 6 is presented a single polymeric material, however, it could, as shown in FIG. 1 a, be assembled as laminated element 6 a of FIG. 1 a, as having a first sheet 6 b with first and second planar surfaces 6 b 1 and 6 b 2 , respectively, composed of a thin flexible “cloth like” polymeric material with its second surface adhesively attached to a less flexible material extending over its essentially the planar second surface. The first sheet could be made of one of many materials or a composite thereof designed to allow the flow of air there through. The less flexible material may be fabricated with or without slits 5 suspended between the inner walls of the proximate cavities.
[0015] FIG. 2 shows a side view of one of the cone springs used in the first embodiment of the shoe of this invention. Cone spring 9 is of identical design and spring steel material type.
[0016] FIG. 3 presents a side view of the discs used to rotatably fix the ends of the springs of the first embodiment of the present invention. The discs are designed to allow the cone springs of FIG. 1 to rotate about the central axis 13 defined by eyelets 17 a and 18 a when small shaped ends 8 a and 9 a are inserted therein.
[0017] In the present invention, the shoe is made in a board last construction. However, it would also be possible to make the shoe of a breathable strobel lasted construction in which the abrasive polymeric material is attached via adhesive to the bottom side of the strobel last to provide an equivalent stiffness bearing surface and through slits for the resistive escape of air from volumes 3 a and 3 b.
[0018] FIG. 4 presents a bottom view of a second embodiment of this invention with a single cone spring in the heel and two cone springs in the forefoot. The outsole 34 and the midsole 35 accepts two transparent discs 16 and 16 e in the forefoot area along with cooperate sized cone springs.
[0019] Even though the springs 8 and 9 are terminated at their small ends 8 a and 9 a with essentially a 90 degree wrist like turn relative to a tangent line to the spiral direction of the last turn, they could have been terminated at their small ends in a normally accepted manner cone springs. The second embodiment of the shoe shown in FIG. 1 of this invention teaches a shoe where cone springs are mounted with their small ends fixably mounted on the transparent discs. FIG. 5 shows a cone spring 26 rigidly mounted on a transparent disc 30 with permanent adhesive 33 as shown in FIG. 5
[0020] The operation of the shoe of this invention will now be discussed. The shoe of this invention is engineered such that the springs mounted in the ball and heel regions of the shoe can pivot in the forward and rearward directions during a foot strike while at the same time providing cushioning of the foot. During a foot strike the spring in a given vacuity forcing the air in that vacuity to flow upward through the throughhole in the laminated closure 6 a attached to midsole 2 or the board last 6 . When the thick broad 6 is used with the midsole 2 the durometer of the EVA of the midsole is chosen such that it minimally interferes with the spring function of the shoe. Alternatively when the laminated closure system is used the thick broad last material is suspended from the walls of the midsole 2 via the Strobel last. | According to the principles of the first embodiment of the present invention, a midsole of a shoe comprising an integral midsole, an outer sole with transparent discs, a board last of tractable stiffness; a mechanical spring located within the midsole; and, an upper shoe body. The shoe being capable of providing line-of-sight viewing of the internally mounted contrivances for structural monitoring throughout the life of the shoe so as to improve durability, process of making comfort and acceptability. | 0 |
BACKGROUND OF THE INVENTION
This invention relates to a drive apparatus equipped with a drive mechanism having a traction-type speed change gear, for use in elevator apparatuses and the like.
Drive apparatuses for elevators are frequently equipped with a drive mechanism having a geared reduction device, with an electric motor connected to the input shaft and a drive sheave connected to the output shaft of the reduction device, and are further equipped with a hoisting rope reeved about the sheave for moving an elevator car. However, geared reduction devices produce considerable noise and vibrations which are transmitted to the building in which the elevator is provided, resulting in a deterioration of the living and working environment in the building. Furthermore, noise and vibrations are transmitted via the hoisting rope to the elevator car, with the result that the passengers within the elevator car are subjected to an unpleasant sensation.
SUMMARY OF THE INVENTION
It is the object of the present invention to provide a drive apparatus which does away with the above-described drawbacks of conventional drive apparatuses, operating silently without vibrations.
It is a further object of the invention to provide a drive apparatus of great safety. These two objects are accomplished by equipping the drive apparatus with a traction-type speed change gear in combination with an abnormality detection device and a control device. The traction-type speed change gear produces smooth, quiet transmission of power from an electric motor to an elevator drive sheave. The abnormality detection device detects when slippage occurs in the speed change gear, and the control device safely brings the elevator to an emergency stop in the event that slippage occurs.
These and other objects of the present invention will become clear upon reading the following description and studying the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross-sectional profile of an elevator apparatus showing one embodiment of a driving apparatus according to the present invention.
FIG. 2 is a partial cross-section of the apparatus of FIG. 1 as viewed from the right of FIG. 1.
FIG. 3 is a block diagram showing the connection between the abnormality detection and control portions of the driving apparatus of FIG. 1.
FIG. 4 is a circuit diagram of an abnormality detection device for use the the embodiment illustrated in FIG. 2.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Below, one embodiment of the present invention will be described as used in an elevator apparatus, while referring to FIGS. 1 through 4.
In the figures, reference numeral 1 indicates an elevator drive mechanism.
Element 2 is a traction-type speed change gear which forms one of the principal parts of the drive mechanism 1.
Element 2a is the housing of the speed change gear 2.
Element 2b is an input shaft which is rotatably mounted in the housing 2a.
Element 2c is a first roller which is secured to input shaft 2b which acts as the sun roller of the speed change gear 2.
Element 2d is an output shaft which is rotatably mounted in the housing 2a.
Element 2e represents support plates which are disposed on one end of the output shaft 2d and located within the housing 2a.
Element 2f represents roller shafts which are rigidly secured at right angles to support plates 2e, and which are located parallel to and equally separated from the cylindrical surface of the first roller 2c.
Element 2g is a frictional body which is secured inside the housing 2a and having a cylindrical inner surface.
Element 2h represents second rollers which are rotatably attached to roller shafts 2f and which are pressed against the cylindrical surface of the first roller 2c and the inner cylindrical surface of the frictional body 2g. These second rollers 2h act as planetary rollers and rotate about the sun roller, first roller 2c.
Element 3 is an electric motor which is connected to the input shaft 2b, by means of which the input shaft is rotated.
Element 4 is a drive sheave which is rigidly connected to the output shaft 2d.
Element 5 is a hoisting rope which is reeved about the drive sheave 4.
Element 6 is an elevator car which is suspended from one end of the hoisting rope 5.
Element 7 is a counterweight which is suspended from the other end of the hoisting rope 5.
Element 8 is a first rotational speed detector of the type well known in the art which measures the rate of rotation of the input shaft 2b and which produces an output voltage corresponding to this rate.
Element 9 is a second rotational speed detector which is also of the type well known in the art and which detects the rate of rotation of the output shaft 2d and which produces an output voltage corresponding to this rate.
Element 10 is an abnormality detection device which compares the outputs from the first detector 8 and the second detector 9, and element 11 is a control device which is activated by the abnormality detection device 10 when the latter determines that the difference between the outputs of first detector 8 and second detector 9 falls outside of a predetermined range.
The operation of the drive apparatus is as follows. When electric motor 3 is activated, it rotates input shaft 2b. This rotation is transmitted to the output shaft 2d through the action of the first roller 2c, the frictional body 2g, and the second rollers 2h.
Namely, when first roller 2c is rotated by the input shaft, traction between the various rollers and the frictional body 2g causes the second rollers 2h, which act as planetary rollers, to rotate about first roller 2c, which acts as the sun roller. The rotation of second rollers 2h is transmitted to the output shaft 2d by the roller shafts 2f and the support plates 2e, and the output shaft is rotated in the same direction as the input shaft but at a slower rate. Thus, the traction-type speed change gear 2 is a reduction gear.
The drive sheave 4 is thereby rotated, and the elevator car 6 and the counterweight 7 are moved by the hoisting rope in mutually opposite directions. The transmission and the change in speed which is carried out by speed change gear 2 consisting of first roller 2c, second roller 2h, etc., is carried out by tractive force, and accordingly, an elevator is obtained which produces little in the way of vibrations and noise.
The traction-type speed change gear 2 can operate only when there is sufficient tractive force between the various rollers and the frictional body. If friction is reduced by abrasion of the rollers, for example, slippage will occur between the rollers of the speed change gear, and transmission of motive force will become difficult or impossible. In the worst case, this slippage could result in the elevator car sliding freely down the elevator shaft as a result of the output shaft 2d rotating independently of the input shaft 2b.
For this reason, first and second rotational speed detectors 8 and 9, abnormality detection device 10, and control device 11 are provided in this drive apparatus. First detector 8 detects the rate of rotation of the input shaft 2b and produces a corresponding voltage. Second detector 9 likewise produces a voltage corresponding to the rate of rotation of the output shaft 2d. As shown conceptually in FIG. 3, these two output voltages are applied to the abnormality detector 10, which compares the voltages. When the difference between the voltages falls outside of a predetermined level, indicating that the input shaft 2b and the output shaft 2d are rotating at disproportionate rates, i.e. that slippage is occurring in the speed change gear 2, the abnormality detection device 10 activates the control device 11. When activated, the control device 11 causes the elevator to make an emergency stop at the nearest floor and issues an alarm.
FIG. 4 shows one example of a circuit for an abnormality detection device, consisting of a comparator portion 12, an absolute value production portion 13, and a threshold detection portion 14.
In the figure, V T8 is the output voltage of first detector 8, which is proportional to the rotational speed of input shaft 2b and V T9 is the output voltage of second detector 9, which is proportional to the rate of rotation of output shaft 2d. V T8 and V T9 are arranged in the circuit so as to be of opposite polarity. V T8 and V T9 are applied to the inverting terminal of a first op-amp 15 through resistors R 1 and R 2 . (R 1 through R 10 are all resistors). The output voltage V OUT of first op-amp 15 is -R 3 (V T8 /R 1 +V T9 /R 2 ), and R 1 and R 2 are chosen so that V OUT is normally 0.
This is possible because, when there is no slippage in the speed change gear, the rotational speed of input shaft 2b is a constant multiple of the rotational speed of output shaft 2d. If the output V T8 of first detector 8 is linearly proportional to the speed of the input shaft 2b and if the output V T9 of second detector 9 is linearly proportional to the speed of the output shaft 2d, then V T8 will be a constant multiple of V T9 as long as no slippage occurs.
Thus, V T8 /V T9 equals a negative constant, -N, which is negative since V T8 and V T9 are of opposite polarity. R 1 and R 2 are chosen such that R 1 /R 2 =-V T8 /V T9 =-N, and accordingly V OUT =-R 3 (V T8 /R 1 +V T9 /R 2 ) is 0 when there is no slippage.
However, if slippage occurs in the traction-type speed change gear, the relationship between V T8 and V T9 will change and V OUT will become non-zero. For example, if the input shaft begins to lag due to slippage, the output V T9 of the second detector will decrease in magnitude and V OUT will go negative. Alternatively, if the output shaft begins to slip and rotate freely due to the torque applied on it by the drive sheave 4, the output V T9 will increase in absolute value, and V OUT will go positive.
V OUT is applied to the input terminals of a second op-amp 16 and this second op-amp 16 outputs a positive voltage proportional to the absolute value of V OUT .
The last part of the circuit is a threshold detection portion 14. When the output of the second op-amp 16 exceeds a predetermined value, corresponding to a certain amount of slippage, the Zener diode 17 begins to conduct, driving the transistor 18, which in turn excites a normally unexcited relay coil 19. When excited, the contact of the relay coil 19 (not shown in the figure) turns on the control device 11, and the elevator is thereby controlled.
By appropriately choosing the resistors, the predetermined value of the second op-amp at which the transistor 18 turns on can be set at any desired level, corresponding to a small or a large amount of slippage in the speed change gear.
The control device 11 is not described here in detail, but may be any device of the type well known in the art which when activated can control an elevator drive mechanism so as to make an emergency stop of the elevator car at the nearest floor and issue an alarm.
The above-described drive apparatus of course has the advantage that it is quieter and produces less vibrations than a drive apparatus using a geared speed change gear, but it also has the advantage that a traction-type speed change gear is cheaper to manufacture. | A drive apparatus for elevators and the like utilizes a traction-type speed change gear to transmit power with little noise and vibrations from an electric drive motor to the drive sheave of an elevator. An abnormality detection device is provided to detect when slippage occurs in the speed change gear, and a control device activated by the abnormality detection device is provided to bring the elevator to a safe emergency stop when such slippage occurs. | 8 |
FIELD OF THE INVENTION
The present relates to turbochargers for internal combustion engines and more particularly to a simplified assembly of and arrangement for lubricating the bearing system of a turbocharger.
BACKGROUND OF THE INVENTION
Turbochargers are widely used on internal combustion engines, and in the past have been particularly used with large diesel engines, especially for highway trucks and marine applications. In distinction to superchargers, which derive their power directly from the crankshaft of the engine, turbochargers are driven by the engine exhaust gases. Exhaust gases are directed to and drive a turbine, and the turbine shaft is connected to and drives the compressor. Ambient air is compressed by the compressor and fed into the intake manifold of the engine.
More recently, in addition to use in connection with large diesel engines, turbochargers have become popular for use in connection with smaller, passenger car power plants. The use of a turbocharger in passenger car applications permits selection of a power plant that develops the same amount of horsepower from a smaller, lower mass engine. Using a lower mass engine has the desired effect of decreasing the overall weight of the car, increasing sporty performance, and enhancing fuel economy. Moreover, use of a turbocharger permits more complete combustion of the fuel delivered to the engine, thereby reducing the hydrocarbon emissions of the engine which contributes to the highly desirable goal of a cleaner environment.
As the use of turbochargers finds greater acceptance in passenger car applications, three design criteria have moved to the forefront. First, the market is demanding that all components of the power plant of a passenger car, including the turbocharger, must provide reliable operation for a much longer period than was demanded in the past. That is, while it may have been acceptable in the past to require a major engine overhaul after 80,000-100,000 miles, it is now necessary to design engine components for reliable operation in excess of 200,000 miles of operation. This means that extra care must be taken to ensure proper lubrication of bearings supporting devices that rotate at very high rotational speeds, as in a turbocharger.
The second design criterion that has moved to the forefront in passenger car applications is that the power plant must meet or exceed very strict requirements in the area of minimized hydrocarbon emissions. Third, with the mass production of turbochargers for smaller passenger cars, it is highly desirable to design a turbocharger that meets the above criteria and is comprised of a minimum number of parts, which parts are easy to manufacture and easy to assemble, in order to provide a cost effective and reliable turbocharger.
As stated above, the demand for engine components that provide an extended service life requires that extra care must be taken to ensure proper lubrication of bearings that support devices rotating at very high rotational speeds, as in a turbocharger. In the prior art, two basic systems have been adopted to deliver lubricating oil to the critical wear points of a turbocharger using two floating journal bearings. First, the central bearing housing can be provided with lubricating oil channels directed to the top of the journal bearings, the so-called “top-delivered” system. With this system, oil is delivered to the top of the journal bearings, usually at the axial center of the bearings, and the bearings are normally provided with radial apertures in the center of the bearing to allow flow of the lubricating oil radially inwardly to the interface between the shaft and the inside diameter of the journal bearing. In this system, the oil must be supplied at high pressure in order to ensure that it will migrate inwardly through an aperture in a journal bearing while the journal bearing is spinning at a very high rate.
The second basic system for delivering lubricating oil to the journal bearings of a turbocharger is to deliver the oil to the center of the rotating shaft and allow the oil to migrate axially outwardly along the shaft and over the bearings before being released to the oil return sump and to the engine crankcase. In both of these systems, in order to provide adequate lubrication to the bearings, a high flow rate of oil has been provided to ensure that adequate coverage of the bearing surfaces is obtained. Especially in connection with the top-delivered system, a high percentage of the oil flowing through the system contacts only the outboard half of the outside diameter of the journal bearing before being expelled into the oil return sump. This means that a very high volume of flow must be provided to obtain any oil film coverage of the other surfaces of the journal bearing.
This high flow of oil through the bearing housing of a turbocharger increases the opportunity for oil to leak from the bearing housing into the turbine or compressor portions of the turbocharger. Internal combustion engines, whether diesel or gasoline, are designed for optimum combustion of the fuel for which they are designed. In either type of engine, when engine crankcase lubricating oil is introduced into the combustion chamber of the engine, it is not burned effectively, and a large portion of that oil is emitted as an undesired hydrocarbon pollutant. Engine manufacturers have been diligent in reducing the amount of lubricating oil that is allowed to enter the combustion chamber of the engine by improving piston ring and valve stem seal designs, and the like. Unfortunately, turbocharger design has not kept pace with this trend.
As stated, turbochargers commonly use crankcase oil to lubricate the rotating bearing interfaces as well as the thrust surfaces that limit axial excursions of the shaft and its turbine and compressor wheels. Since turbochargers operate at extremely high rotational speeds, sometimes in excess of 200,000 RPM, generous lubrication of these bearing surfaces is critical in order to provide a turbocharger capable of a long and reliable service life. With this high flow rate of oil over the journal bearings comes the possibility that some percentage of the oil will escape past the barriers set up in the turbocharger to prevent lubricating oil from entering either the turbine housing or the compressor housing.
More specifically, if lubricating oil from the center bearing housing migrates beyond the piston ring seal provided to prevent such migration at the turbine end of the housing, lubricating oil will enter the turbine housing and will be expelled with the exhaust flow out of the engine into the atmosphere. On the other hand, if lubricating oil from the center bearing housing migrates beyond the piston ring seal at the compressor end of the housing, the lubricating oil will enter the compressor housing and will be injected into the combustion chamber of the engine where it will not be properly burned and will be emitted by the engine as an undesired hydrocarbon pollutant. Unfortunately, as a result of this phenomenon, it is commonly believed that over half of the hydrocarbon emissions of turbocharged engines come from oil leakage through the turbocharger, not from the engine itself.
Thus, it seems that these two design criteria point a designer in different directions. That is, if it is desired to achieve longer service life of a turbocharger, the flow of oil over the bearings should be increased to minimize metal-to-metal contact between parts and decrease wear of the parts. On the other hand, if hydrocarbon emissions of the engine are to be decreased, oil flow through the bearing housing should be minimized to decrease the opportunity for oil leakage into the turbine or compressor housings of the turbocharger.
Many attempts have been made to minimize leakage of oil from a turbocharger bearing housing, but these have always taken the form of adding a number of parts or a new sub-assembly, such as an oil deflector, extra seals, or the like. While this may assist in reducing oil leakage from the bearing housing, it is contrary to the third design criterion mentioned above. That is, adding more parts or a new sub-assembly tends to make the turbocharger more complicated and expensive, when it is desired to make the turbocharger simpler and easier to manufacture and assemble.
An earlier attempt at providing a simplified bearing system is shown in U.S. Pat. No. 3,993,370 to Woollenweber. That patent shows a bearing system in which the journal bearings are constrained to ride on the bearing lands of the center housing by a shoulder of the center housing on the inboard side of the bearings, and by a shoulder formed on the shaft at the turbine end and a thrust collar that rotates with the shaft at the compressor end of the center housing. With this arrangement, none of the thrust-bearing surfaces is between the shaft, which rotates at very high speed, and a stationary surface. Rather, the thrust-bearing surfaces are between the end surfaces of the journal bearings, which rotate at speeds less than the speed of the shaft, and either a stationary surface on the housing or a shoulder or collar carried by the shaft. Thus, the bearing assembly of Woollenweber provides reduced relative speed between the rotating assembly of the turbocharger and the thrust-bearing surfaces on the combined journal and thrust bearings, regardless of the direction in which the thrust force acts, and the conventional thrust bearing assembly has been eliminated.
Lubrication is still provided in the conventional manner of a positive pressure, top-delivered system that requires oil flow radially inwardly through a spinning bearing in order to deliver lubricating oil to the rotating interface between the shaft and the inside diameter of the journal bearing. A radial aperture through the journal bearing is provided for that purpose.
Another simplified bearing system is shown in Swiss Patent No. 407,665 to Buechi. That patent shows, in the context of a turbocharger, a pair of floating bearings constrained to float at their respective bearing lands within a center housing (See FIGS. 1 and 2 ). On the outboard side, the bearings are constrained from axial movement by a collar that is carried by the shaft. On the inboard side, the bearings are constrained by axial abutment surfaces on a pair of rings, which in turn are held in their axial position by conventional snap rings.
Oil is delivered centrally between the bearings and is allowed to migrate axially outwardly along the shaft to reach the bearings. It is not clear whether any attempt is made to balance the oil pressure on various surfaces of the bearings or to control the flow of oil over those surfaces to achieve maximum efficiency of lubrication of the bearings with minimum flow rate of oil. It is clear that no axial aperture is provided through the bearing, nor is any axial groove provided in the inside diameter or the outside diameter of the bearing to provide a means for controlling the flow rate of oil across the journal bearings. As a further indication that such control is not present, it is noted that Buechi believed two piston rings were required in each axial direction to control undesired oil flow into either the turbine or compressor housings.
It appears that if the Buechi structure employed normal bearing clearances between the journal bearing and the shaft, and between the journal bearing and the housing, the flow of oil around the journal bearing would be too low to provide adequate lubrication to the thrust surfaces at the axial ends of the journal bearings. On the other hand, if the clearances between the journal bearing and the shaft, and between the journal bearing and the housing, were large enough to provide oil flow adequate to lubricate the thrust bearings, the journal bearings would not provide stable rotational support for the shaft and the turbine and compressor wheels.
SUMMARY OF THE INVENTION
It is therefore a primary object of the invention to provide a turbocharger bearing system characterized by a highly efficient, controlled lubrication system that permits excellent lubrication of the bearings with a minimum of oil flow through the bearing housing, thereby providing a turbocharger that is reliable and durable in operation.
Another object of the invention is to provide a turbocharger bearing assembly that will significantly reduce the amount of oil that is leaked into the engine intake or exhaust streams, thereby greatly reducing the hydrocarbon emissions of the engine.
A further object of the invention is to accomplish the above objects while providing a turbocharger bearing assembly that is greatly simplified, being comprised of a reduced number of parts, each of which is easy to manufacture, and which are easy to assemble to form a turbocharger that is efficient and durable in operation.
In accordance with the present invention, these and other objects are achieved by providing a greatly simplified turbocharger assembly that allows accurate and efficient control of oil flow over the bearings, thereby permitting excellent lubrication of the bearings with a reduced amount of oil flow through the bearing housing, resulting in significantly lower hydrocarbon leakage from the turbocharger into the engine or engine exhaust, and ultimately lower hydrocarbon emissions by the engine. In a preferred embodiment of the invention, this is accomplished by receiving a turbocharger shaft in a central bore in the bearing housing and supporting that shaft on a pair of floating journal bearings riding on bearing lands formed in the housing. The journal bearings are axially constrained on their inboard sides by a shoulder in the bearing bore of the housing and on their outboard side by a step in the shaft at the turbine end of the bearing housing and by a flinger sleeve carried by the shaft at the compressor end of the bearing housing. The flinger sleeve is held in place on the shaft by the compressor wheel, which in turn is threaded onto the shaft by cooperating threads at the nose of the compressor wheel, thereby eliminating the need for a washer and/or nut for attaching the wheel.
To provide lubrication to the bearings, a central lubrication inlet port is provided in the housing in communication with the central bore between the bearing lands. Lubricant proceeds from the inlet port axially in both directions along the shaft through a gap between the shaft and the central bore to the journal bearings. At the journal bearings, the lubricant flows between the shaft and the journal bearings, past the axial ends of the journal bearings to lubricate the axial thrust surfaces formed thereon, and over the journal bearings to lubricate the rotating interface between the journal bearings and the housing.
In order to control oil flow through the housing and balance oil pressure around the journal bearings, great care is taken to size the various passages through the housing and around the bearings, and an axial passage is provided in the bearings extending from the inboard end of the bearings to the outboard ends thereof. This axial passage can take the form of a bore through the bearing, or a groove in the inner and/or outer diameter of the bearings.
More specifically, the passages begin with the inlet port that has a first cross sectional area. The oil then proceeds to an axial channel defined by the difference between the area of the central housing bore and the cross sectional area of the shaft disposed in the bore. This difference must be multiplied by two since the oil flow proceeds in two axial directions. If the size of the bore or the shaft is different in the two axial directions, this must be taken into account in determining the total cross sectional area of the combined axial channels. It is also possible that these axial channels may not have a constant cross sectional area along their axial extent. That is, either the central bore in the housing or the portion of the shaft disposed in the central bore could be tapered causing the cross sectional area to change along the axial length of the channel. In this instance, the area under consideration that determines oil flow is the smallest cross sectional area in that channel.
The third area to be controlled to achieve the desired flow of oil across the journal bearings is the total area available for oil flow over, under, around and through the journal bearings in the bearing lands of the housing. This area can be defined as the total area of the bearing lands minus the cross sectional area of the shaft disposed in the bearing lands, minus the cross sectional area of the journal bearings, which does not include the area of any aperture or groove in the journal bearing. Again, the sum in both axial directions must be considered to determine the total area of the third channel.
In general, the areas must be arranged so that the first area is equal to or greater than the area of the third channel around the journal bearings. In order to achieve an oil flow rate adequate to lubricate the axial end thrust surfaces of the journal bearings, an axial passage must be provided in the journal bearings, either under, over, or through the journal bearings. As a result, the flow area through the third channel will necessarily be greater than the flow area over a journal bearing located in the third channel with no axial apertures or grooves provided for this purpose. Since the journal bearings of the present invention act as both rotational journal bearings and as thrust bearings, it is important that all faces, both radial and axial, receive adequate lubrication. This is accomplished by metering the flow rate of oil across the bearings by use of an aperture or groove in the journal bearings, thereby providing a flow rate that is greater than would have been available if no such aperture or grooves were included, and less than the wasteful and polluting quantities of oil emitted into the atmosphere when a top-delivered system of lubrication is used. With this arrangement, an adequate flow rate of oil can be maintained to keep to keep the inside and outside diameter portions of the journal bearings properly lubricated, and to provide adequate lubrication to the axial thrust surfaces of the journal bearings, while still keeping the total flow rate of oil to a minimum to reduce the potential for oil leaking to the turbine or compressor housings and thus creating unwanted hydrocarbon emissions.
Preferably, the channels proceeding in the two axial directions from the inlet port are symmetrical for ease of manufacture of the parts and for uniform control of oil flow in the two directions. In addition, the journal bearings themselves are preferably identical. Alternatively, it may be desirable to provide a greater flow rate of oil in one direction than in the other. For example, it may be desirable to provide a greater flow of oil over the journal bearing at the turbine end of the bearing housing than that provided at the compressor end because the turbine end is hotter and the journal bearing at that end needs more cooling effect from the oil flow. To accomplish this, the cross sectional areas of the axial channels leading to the journal bearings can be adjusted to promote this uneven flow. Further, the cross sectional area of the oil flow channels in the region of the bearing lands can be modified so that an increased flow is permitted over the journal bearing at the turbine end of the bearing housing as compared to the flow over the journal bearing at the compressor end of the bearing housing. In a preferred embodiment of the invention, the cross sectional area of the combined, axial channels is less than the area of the inlet port and greater than the cross sectional area of the third channel around the journal bearings.
To promote axial flow of lubricating oil away from the journal bearing at the turbine end of the bearing housing, the shoulder of the shaft is provided with an abutment surface to abut the outboard end of the journal bearing, and that abutment surface has an outer diameter substantially less than the outer diameter of the journal bearing. To direct oil flow from the journal bearing into the oil return sump and away from the turbine housing, the shoulder has an increased diameter portion axially spaced from the journal bearing for flinging oil off of the shaft before it can migrate toward the turbine end of the shaft. Similarly, a flinger sleeve at the compressor end of the bearing housing has an abutment surface to abut the outboard end of the journal bearing at the compressor end of the housing, and that abutment surface has an outer diameter substantially less than the outer diameter of the journal bearing. Also, the flinger sleeve has an increased diameter portion axially spaced from the journal bearing for flinging oil off of the shaft before it can migrate toward the compressor end of the shaft.
In a preferred embodiment of the invention, the journal bearings are provided with chamfers at the intersection of the inner surface and the outer surface with the inboard and outboard ends of the bearings. In order to promote flow of lubricating oil to the interface between the shaft and the journal bearing, the chamfer at the intersection of the inner surface of the bearing with the inboard and outboard ends is greater than the chamfer at the intersection of the outer surface with the inboard and outboard ends.
Since the journal bearings of the present invention serve both as journal bearings for rotationally supporting the turbocharger shaft and as thrust bearings for limiting axial excursions of the shaft, the axial end faces of the journal bearings are preferably provided with radial grooves to promote flow of oil across those thrust surfaces. To permit the journal bearing end faces to serve as effective thrust bearing surfaces, the radial grooves preferably have adjacent ramp portions leading to flat thrust bearing lands on the end faces. In the most preferred embodiment of these bearings, the radial grooves have adjacent ramp portions leading to flat thrust bearing lands on both sides of said grooves forming symmetrical thrust surfaces on said inboard and outboard ends. With this arrangement, the journal bearings can themselves be symmetrical so that they can be assembled in the turbocharger assembly in either axial direction, thereby simplifying the assembly step and making it easier to manage.
In summary, concerning the above-described structure, it is noted that complicated turbochargers in the prior art often are constructed of more than one hundred parts. Even relatively simple turbochargers commonly used today are comprised of forty parts or more. Remarkably, the turbocharger of the present invention provides a fully functional turbocharger that is efficient and durable in operation and is comprised of a total of twelve parts.
Lastly, a method for lubricating a rotating shaft is disclosed that employs a turbocharger structure as set forth above and includes the steps of supplying the bearing housing with a lubricant under pressure, and channeling that lubricant through a series of lubricant transmission channels, the last such channel having a cross sectional area equal to or smaller than the first channel. Preferably, each successive channel has a cross sectional area equal to or smaller than the preceding channel. The method further includes the step of balancing the pressure of the lubricant to achieve substantially equal pressure on all faces of the journal bearings in the bearing lands, and the step of forming a lubricant film on the end thrust surfaces of the journal bearings.
In all of the above-described embodiments of the invention, the apparatus employed to practice this invention is relatively easy to manufacture and has a minimum number of parts. In addition, the lubrication system is efficient and effective, thereby producing a turbocharger capable of a very long useful life while still reducing the amount of lubricant necessary to achieve these ends, and, therefore, significantly reducing the amount of hydrocarbon emissions caused by the turbocharger.
These and other aspects of the invention will be more apparent from the following description of the preferred embodiments thereof when considered in connection with the accompanying drawings and appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention is illustrated by way of example and not limitation in the accompanying drawings in which like references indicate similar parts, and in which:
FIG. 1 is a front elevational view, taken in section, of a turbocharger incorporating a bearing and lubrication system in accordance with one embodiment of the invention;
FIG. 2 is an enlarged, perspective view of the journal bearing employed in the turbocharger of FIG. 1;
FIG. 3 is a further enlarged, fragmentary view of a portion of the journal bearing of FIG. 2, taken along the line 3 — 3 of FIG. 2, and illustrating some details of that portion of the journal bearing;
FIG. 4 is a perspective view of a journal bearing, as in FIG. 2, but illustrating an alternative embodiment of a journal bearing for use in connection with the turbocharger of the present invention; and
FIG. 5 is an end view of the journal bearing of FIG. 4, taken along the line 5 — 5 of FIG. 4 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
A turbocharger assembly is generally shown at 10 in FIG. 1 and is comprised of a turbine housing 12 , a compressor housing 14 , and a bearing housing 16 disposed between the turbine and compressor housings. The turbine housing 12 is attached to one end of the bearing housing 16 by a V-band clamp 18 that allows the turbine housing to be oriented in any desired rotational orientation to the bearing housing as may be required by the geometry of a particular customer's engine compartment. Similarly, the compressor housing 14 is attached to the opposite end of the bearing housing 16 by another V-band clamp 20 , which also permits the compressor housing to be positioned in any desired rotational orientation with respect to the bearing housing, as customer's needs may dictate.
A turbine wheel and shaft assembly 22 is disposed in the turbocharger 10 with the turbine wheel 24 surrounded by the turbine housing 12 and the shaft 26 extending through the bearing housing 16 and into the compressor housing 14 . A compressor wheel 28 is mounted on the distal end of the shaft 26 and is disposed in the compressor housing 14 . In the embodiment illustrated, the compressor wheel 28 is secured to the shaft 26 by internal threads 30 formed in the nose portion 32 of the compressor wheel, which threads cooperate with external threads on the distal end of the shaft 26 . To complete the rotating assembly, a flinger sleeve 34 is mounted for rotation with the shaft 26 by being captured between a shoulder 36 on the shaft and the compressor wheel 28 .
To receive the shaft 26 in the bearing housing 16 , the bearing housing 16 has a central bore 38 , and the central bore 38 includes a pair of enlarged diameter portions forming bearing lands 40 and 42 . To rotationally support the shaft 26 and the turbine and compressor wheels, a pair of rotationally floating journal bearings 44 and 46 are received in the bearing lands 40 and 42 , respectively. The bearings 44 and 46 are axially constrained to float on their respective bearings lands 40 and 42 , on their inboard sides, by shoulders 48 and 50 that are formed in the bearing housing 16 where the central bore 38 steps up to a larger diameter to form the bearing lands 40 and 42 . The bearings 44 and 46 are axially constrained to float on their respective bearings lands 40 and 42 , on their outboard sides, by a shoulder 52 on the shaft 26 at the turbine end of the bearing housing 16 , and by the flinger sleeve 34 at the compressor end of the bearing housing 16 .
When in operation, the shaft 26 of the turbocharger 10 is often subjected to axial thrust forces that may operate in either axial direction during different phases of operation. To keep the rotating assembly of the turbocharger of the present invention in its desired axial position within the turbocharger, the journal bearings 44 and 46 also act as thrust bearings. That is, when axial thrust forces are acting on the rotating assembly from the turbine end toward the compressor end, the shoulder 52 on the shaft 26 will bear against outboard end of the journal bearing 46 , and the inboard end of the bearing 46 will contact the shoulder 50 on the inboard side of the bearing land 42 to limit axial movement of the rotating assembly toward the compressor end of the turbocharger. Conversely, when axial thrust forces are acting on the rotating assembly from the compressor end toward the turbine end, the flinger sleeve 34 will bear against outboard end of the journal bearing 44 , and the inboard end of the bearing 44 will contact the shoulder 48 on the inboard side of the bearing land 40 to limit axial movement of the rotating assembly toward the turbine end of the turbocharger. With this simple arrangement, the often complicated and expensive conventional thrust bearing assembly can be completely eliminated.
In order to lubricate the bearing system described above, a lubricant, which is normally engine crankcase lubricating oil, is introduced under pressure through a lubricant inlet port 54 formed in the bearing housing 16 . The inlet port 54 is a simple straight bore in the housing 16 that communicates with the central bore 38 in the bearing housing. From the inlet port 54 , lubricant migrates axially outwardly along the shaft 26 in both axial directions in the space between the shaft 26 and the central bore 38 toward the journal bearings 44 and 46 . When the lubricant reaches the journal bearings 44 and 46 , it is constrained to flow through a plurality of flow paths around the journal bearings and into a pair of oil collection spaces 56 and 58 , and from there into an oil collection sump 60 where it is returned to the engine crankcase in a conventional manner.
In order to control the flow of lubricating oil through the bearing assembly described above and achieve optimum lubrication of the bearings with a minimum flow rate of oil, the cross sectional areas of the various channels through which the oil flows is carefully planned to ensure that the bearings are constantly surrounded by an oil film. More specifically, three distinct channels of oil flow are considered and regulated by design in order to achieve the desired results. First, the inlet port 54 is formed to have a known first cross sectional area. Second, the axial flow channels from the inlet port 54 to the journal bearings 44 and 46 have a cross sectional area defined by the area of the central bore 38 minus the area occupied by the shaft 26 . Since these axial flow channels extend in two axial directions from the inlet port 54 , the cross sectional area defined above must be doubled to compare it with the area of the inlet port 54 . Also, if the area of either the bore 38 or the shaft 26 is different on opposite sides of the inlet port 54 , this must be considered in determining the effective area of the second flow channel. Preferably, the bore 38 has a constant diameter between the bearing lands 40 and 42 in the bearing housing 16 , and the shaft 26 also has a constant diameter in the portion disposed between the bearing lands 40 and 42 . Even if these axial flow channels have a varying cross sectional area, the minimum cross sectional area will be considered for flow control purposes.
Lastly, the third channel of oil flow is defined by the paths through which oil must flow to move from the inboard side of the journal bearings 44 and 46 to the outboard side of the bearings. The cross sectional area of this third channel is thus defined by the cross sectional area of the bearing lands 40 and 42 , minus the area represented by the portion of the shaft disposed in the bearings lands 40 and 42 , and minus the area represented by the cross section of the journal bearings 44 and 46 . In this regard, it should be noted that the cross sectional area of the journal bearings does not include any area of that cross section that is represented by an axially extending aperture or groove through the bearing.
In general, the design criterion for controlling oil flow over the journal bearings is that the area of the first flow channel must be equal to or greater than the area of the third flow channel to provide predictable, pressurized, and metered oil flow to the journal bearings 44 and 46 and to the bearing lands 40 and 42 . Moreover, to achieve the desired balance of oil flow over the journal bearings 44 and 46 within the third oil flow channel, care must be taken to regulate the size of the various oil flow paths within the third oil flow channel.
The object within the third oil flow channel is to provide full 360 degree surrounding of the journal bearings 44 and 46 with a lubricating oil film so that no metal-to-metal contact is made, in order to achieve the desired long service life of the turbocharger bearing assembly. To achieve this, the clearance between the journal bearing inside diameter and the shaft 26 , and the clearance between the journal bearing outside diameter and the bearing lands 40 and 42 are regulated to achieve a balanced flow under and over the journal bearings. In addition, to balance oil pressure on the axial ends of the journal bearings 44 and 46 , an axial lubricant communication means is formed in the journal bearings. This axial lubricant communication means can take the form of an axial aperture through the bearing or an axial groove extending from the inboard end of the bearing to the outboard end.
Because the journal bearings 44 and 46 rotate at high speed (although not at the speed of the shaft 26 ), oil delivered to the journal bearings 44 and 46 tends to be forced to the outer diameter of the bearings. Since there is a significant difference in rotational speed of the shaft 26 and the journal bearings 44 and 46 , it is critical that the interface between the shaft and the journal bearings be well lubricated. For that purpose, chamfers are provided at the intersection of the inner surface and the outer surface of the journal bearings 44 and 46 with the axial end surfaces of the journal bearings, and the chamfer at the intersection of the inner surface of the journal bearings with the end surfaces thereof is greater than the chamfer at the intersection of the outer surface and the end surfaces.
After the oil has flowed across the journal bearings 44 and 46 , it is released into a space in the bearing housing 16 outboard of the bearing lands 40 and 42 . It is at this point that the turbocharger may leak lubricating oil into either the turbine or compressor housings and create undesired hydrocarbon emissions by the engine. To prevent or at least minimize this, the turbocharger of the present invention is provided with a system for allowing free flow of oil axially away from the journal bearings, while minimizing the opportunity for that oil to enter either the turbine or compressor housings.
For this purpose, the shoulder 52 on the shaft 26 at the turbine end of the shaft presents an abutment surface 62 to the outboard end of the journal bearing 46 , and the abutment surface 62 has an outside diameter substantially less than the outer diameter of the journal bearing 46 . This reduced outer diameter of the abutment surface 62 permits free flow of lubricating oil off of the journal bearing 46 into the oil collection space 58 . To discourage further migration of lubricating oil toward the turbine housing, the shoulder 52 is provided with an increased diameter portion 64 , axially spaced from the journal bearing 46 , for flinging oil off of the shoulder 52 before that oil is allowed to migrate axially toward the turbine.
Similarly, the flinger sleeve 34 at the compressor end of the shaft presents an abutment surface 66 to the outboard end of the journal bearing 44 , and the abutment surface 66 has an outside diameter substantially less than the outer diameter of the journal bearing 44 . This reduced outer diameter of the abutment surface 66 permits free flow of lubricating oil off of the journal bearing 44 into the oil collection space 56 . To discourage further migration of lubricating oil toward the compressor housing, the flinger sleeve 34 is provided with an increased diameter portion 68 , axially spaced from the journal bearing 44 , for flinging oil off of the flinger sleeve 34 before that oil is allowed to migrate axially toward the compressor housing.
In order to provide a seal to prevent migration of lubricating oil from the bearing housing 16 into either the turbine housing 12 or the compressor housing 14 , a pair of piston rings 70 are provided to seal the interface between the shoulder 52 and the bearing housing 16 , and between the flinger sleeve 34 and the bearing housing 16 .
To illustrate further details of the turbocharger of the present invention, FIG. 2 is a perspective view of one of the journal bearings 44 or 46 . As a feature of the ease of manufacture of the turbocharger of the present invention, the journal bearings 44 and 46 are preferably identical. As seen in FIG. 2, the axial end face 72 of the journal bearing 44 is provided with a plurality of radial grooves 74 to permit radial flow of lubricating oil across the end face 72 , thereby lubricating the thrust surface between the journal bearing 44 and the shoulder 48 on the bearing housing 16 . In this instance, eight such radial grooves are illustrated, circumferentially spaced 45 degrees from one another. It will be appreciated that these radial grooves 74 are formed in both ends of the journal bearing 44 , and in both ends of the journal bearing 46 . As a consequence, they serve to lubricate all four thrust surfaces on the axial ends of the journal bearings 44 and 46 . Any suitable number of such grooves will suffice, but eight is currently preferred.
It is further apparent from the illustration in FIG. 2 that the journal bearing 44 (and 46 ) has a plurality of axial apertures extending through the journal bearing from one axial end to the other. In this case, four such apertures are illustrated, coinciding with every other radial groove 74 , but it will be apparent that any other suitable number of such apertures will suffice.
As can best be seen in FIG. 3, the radial grooves 74 are preferably accompanied by adjacent ramp surfaces 78 leading to and intended to form a lubricating film at a flat thrust land surface 80 coincident with the axial end face 72 of the journal bearings 44 and 46 . Preferably, the radial groove 74 forms an angle of about 120 degrees, and the ramp surfaces 78 form an angle with the flat thrust land surface 80 of about 2-3 degrees. In the most preferred embodiment of the journal bearings, the ramp surfaces 78 extend circumferentially from the grooves 74 in both circumferential directions so that the journal bearings 44 and 46 can be assembled in either axial direction on the shaft 26 , and without regard to the rotational direction of the shaft 26 .
FIG. 4 illustrates an alternative journal bearing 82 for use with the turbocharger of the present invention. Journal bearing 82 is similar in all respects to the journal bearings 44 and 46 except that the journal bearing 82 is provided with axial grooves 84 in the inside diameter of the journal bearing extending from the inboard end of the journal bearing to the outboard end. In addition, the bearing 82 may be provided with axial grooves 86 in the outside diameter of the journal bearing extending from the inboard end to the outboard end thereof. It will be understood that these grooves can be provided on either the inside or outside diameter of the journal bearing, or both.
FIG. 5 is an end view of the journal bearing 82 clearly showing the axial grooves 84 in the inside diameter of the journal bearing and the axial grooves 86 in the outside diameter of the journal bearing.
Lastly, a method for lubricating a rotating shaft is disclosed that employs a turbocharger 10 as set forth above and includes the steps of supplying the bearing housing 16 with a lubricant under pressure, and channeling that lubricant through a series of lubricant transmission channels, the first such channel having a cross sectional area equal to or greater than the last channel. The method also includes the step of channeling the lubricant through a series of three lubricant transmission channels, each successive channel having a cross sectional area equal to or smaller than the preceding channel. The method further includes the step of balancing the pressure of the lubricant to achieve substantially equal pressure on all faces of the journal bearings in the bearing lands, and the step of forming a lubricant film on the end thrust surfaces 80 of the journal bearings 44 and 46 .
Various modifications and changes may be made by those having ordinary skill in the art without departing from the spirit and scope of this invention. Therefore, it must be understood that the illustrated embodiments of the present invention have been set forth only for the purpose of example, and that they should not be taken as limiting the invention as defined in the following claims.
The words used in this specification to describe the present invention are to be understood not only in the sense of their commonly defined meanings, but to include by special definition, structure, material, or acts beyond the scope of the commonly defined meanings. The definitions of the words or elements of the following claims are, therefore, defined in this specification to include not only the combination of elements which are literally set forth, but all equivalent structure, material, or acts for performing substantially the same function in substantially the same way to obtain substantially the same result.
In addition to the equivalents of the claimed elements, obvious substitutions, now or later known to one of ordinary skill in the art, are defined to be within the scope of the defined elements.
The claims are thus to be understood to include what is specifically illustrated and described above, what is conceptually equivalent, what can be obviously substituted, and also what incorporates the essential idea of the invention. | A greatly simplified turbocharger assembly comprised of a minimum number of parts allows accurate and efficient control of oil flow over the bearings ( 44,46 ), thereby permitting excellent lubrication of the bearings with a reduced amount of oil flow through the bearing housing ( 16 ), resulting in significantly lower hydrocarbon leakage from the turbocharger into the engine or engine exhaust, and ultimately lower hydrocarbon emissions by the engine. | 5 |
CROSS-REFERENCE TO RELATED APPLICATION
The present application claims the benefit of previously filed Provisional Patent Application, Ser. No. 60/623,113, filed Oct. 29, 2004, and incorporates by reference the contents therein.
FIELD OF INVENTION
This invention relates to a system which allows for application of a composition to a person and can be easily used in the user's home, for example a sunless tan applied in the user's own shower, and more specifically for a high-pressure, gas powered, hands free, full body self misting device.
BACKGROUND OF INVENTION
The cosmetic effect of tanned skin has long been a desired goal for many people. This desire has led to the development of a large and varied industry supplying compositions and devices to facilitate natural or UV radiation induced tanning of the skin. Another market has also developed for compositions to more rapidly provide the visual effect of tanned skin without UV radiation exposure. In addition to the development of the multitude of sun tanning, sun screening, and artificial tanning and bronzing lotions, creams, and oils now available, various applicator devices for the different compositions have been devised, ranging from simple squeeze bottles, pump sprays, and aerosols, to hand-held spray systems powered by electric compressors, fans, or pumps, to elaborate spray rooms that generate mists of suntan lotions or artificial tanning compositions for application to a user standing in the room.
These various applicator devices include U.S. Pat. No. 1,982,509 issued to Frank showing a belt-driven carriage apparatus in a vertically oriented cabinet designed to carry, among several alternatives, a compressed air sprayer head and one or more reservoirs for liquid or powder compositions to be spray applied through the sprayer head to all or part of the body of a user standing in front of the apparatus. The '509 patent does not disclose the spray application of tanning compositions, and the single spray nozzle would necessarily result in an uneven application in overlap areas as the user turns for sequential sprayer passes, and/or missed areas under the arms or on the insides of the arms and legs. The belt driven carriage of the '509 patent is raised and lowered along a guide pole in the cabinet with the start and stop positions for the carriage and the activation of the sprayer apparatus being coordinated by a complicated set of electromechanical linkages and trip-switches.
U.S. Pat. Nos. 5,460,192 and 5,664,593, both to McClain, describe variations of an apparatus to coat a user's body up to the neck with suntan lotion or sunscreen. Both variations provide for a cylindrical enclosure in which the user stands with head and neck protruding through a hole in the top of the enclosure. The apparatus of the '192 patent provides for three liquid spray nozzles directed at the shoulder level, the waist level, and at the level of the legs, respectively. When activated by a user, the apparatus sprays a dose of suntan lotion or sunscreen while the user rotates while standing. Excess spray is drained through a grating at the base of the enclosure. The apparatus of the '593 patent atomizes the lotion into a forced-air stream which then enters the enclosure through three ports at the level of the shoulder, the waist, and the legs, respectively. An evacuation fan draws air from within the enclosure through a vent close to the base of the enclosure, creating more air turbulence in the enclosure and also recirculating excess atomized lotion from the air in the enclosure back into the forced-air stream in an effort to more efficiently and more completely coat the user's body. The user's body must still rotate within the enclosure, while the user's neck protrudes through the close fitting hole in the top of the enclosure. The apparatus of the '593 patent also collects condensed over-spray from the recirculated air with the evacuation fan mechanism, as well as draining excess over-spray from the enclosure through a grating in the enclosure base.
U.S. Pat. No. 5,922,333 and others issued to Laughlin generally describe a method of applying a wide variety of fluids to the body, including sunless tanning compositions, by manually directing a spray nozzle at the area to be coated, or preferably, by atomizing the fluid into an air current and directing the air current against the person being coated, and collecting the residual spray through a venting system, preferably including a filtration means.
Still other apparatuses, such as that disclosed in U.S. Pat. No. 6,443,164 issued to Parker, et al., provide for a booth-type enclosure with a multiplicity of fixed spray nozzles at various heights in the corners of the booth. These have fixed or moving nozzles that direct a spray of artificial tanning composition at the user standing in the center of the booth. Upon completion of a spray cycle, an evacuation fan evacuates residual spray from the booth through a filtered venting system.
These devices, along with all other prior art sunless tanning devices and booths presently on the market, have major drawbacks including incomplete and/or streaky application of tanning composition, inefficient use of tanning composition, complicated equipment that requires trained operators to use, and discomfort, including possible embarrassment for the user due to the need to undress and use a public location or have another person's assistance to get a full body tan as compared with the easy hands free and private use in the user's own shower that the device of this disclosure allows.
BRIEF SUMMARY OF THE INVENTION
The high-pressure gas powered full body self misting device, henceforth designated as the device, is an apparatus that allows a person to spray a mist onto their whole body at once without using electricity, and without having to hold anything in their hands, such as a can or misting spray wand. This device can be used as a simple, do-it-yourself, misting system for fluids that are commonly applied to, or around, the body including, but not limited to, tanning solution, skin lotions, and aromatherapy mist.
For operation of the invention, the pressure vessel is first filled with a fluid through the fill valve, which is closed after filling. A gas cartridge is then connected to the gas release valve. When the gas is released via the gas release valve, the high-pressure gas from the gas cartridge pressurizes the fluid in the pressure vessel, which is then forced out through the manifold and further through mist nozzles. Depending on the applied use of the invention, the operator may stand in front of the mist nozzles to apply the mist to their skin.
It is therefore an object of the invention to supply a simple, easy to use spray misting device that a user can use in the privacy of their own home.
For a fuller understanding of the nature and objects of the invention, reference should be made to the following detailed description taken in connection with the accompanying drawings.
BRIEF DESCRIPTION OF DRAWINGS
For a fuller understanding of the nature and objects of the invention, reference should be made to the accompanying drawings, in which:
FIG. 1 : shows a schematic drawing of the mechanical features of the device;
FIG. 2 : shows a drawing of the preferred embodiment of the device in a collapsed for easy handling position; and,
FIG. 3 : shows a drawing of the preferred embodiment of the device in the deployed position.
DESCRIPTION OF PREFERRED EMBODIMENT
As shown in the FIG. 1 schematic the basic system components that make up the device ( 1 ) include a gas release valve ( 2 ), pressure vessel ( 3 ), fill valve ( 4 ), manifold ( 5 ) with mist nozzles ( 6 ), nozzle support system ( 7 ), and preferably a drain valve ( 8 ), although this component is not a necessity for operation. These components are used together with a mistable fluid that has been entered into the pressure vessel ( 3 ) through the fill valve ( 4 ), and a high-pressure gas cartridge ( 9 ), which is used to propel the mistable fluid out of the pressure vessel ( 3 ), through the manifold ( 5 ), and to the misting nozzles ( 6 ).
The gas release valve component ( 2 ) can be as simple as a fixed puncture pin (not shown) that pierces a gas cartridge ( 9 ) when it is pressed against the pin, or, as shown on FIGS. 2 and 3 , it can consist of a movable puncture pin (not shown) connected to an actuation device ( 10 ) such as a foot pedal. The gas release valve ( 2 ) can be a separate component connected to the pressure vessel ( 3 ) through high-pressure pipe or tubing, or it can be directly connected or integral to the pressure vessel ( 3 ) as shown in the preferred embodiment.
The pressure vessel ( 3 ) is a container that is capable of holding the fluid added by a user and is also capable of being pressurized with gas, which comes from the gas cartridge ( 9 ) when released by the gas release valve ( 2 ), to expel the fluid at a high pressure. The pressure vessel ( 3 ) can be any size or shape container suitable for holding the pressure of the particular gas cartridges ( 9 ) being used (standard commercially available CO2 gas cartridges are pressurized at about 860 psi at room temperature). Other types of gas cartridges can be used as is easily determined by those skilled in the art.
The fluid fill ( 11 ) and fill valve ( 4 ) allows for the fill of a mistable fluid into the pressure vessel ( 3 ). Once the pressure vessel ( 3 ) is filled the fill valve ( 4 ) is closed before the gas release valve ( 2 ) is activated so the fluid and/or gas cannot escape back through the fill valve ( 4 ) and is instead propelled through the manifold ( 5 ) and out through the misting nozzles ( 6 ). The fill valve ( 4 ) can simply be a threaded port into the pressure vessel ( 3 ) with a threaded plug for closure, or it can consist of a high-pressure ball, or other type, open/close valve well known by those skilled in the art. The fill valve ( 4 ) could also be a separate component connected to the pressure vessel ( 3 ) through high-pressure pipe or tubing, or it can be directly connected or integral to the pressure vessel ( 3 ). The fill valve ( 4 ) could also be integral to the gas release valve ( 2 ).
The manifold ( 5 ) connects the mist nozzles ( 6 ) that are simply a series of one or more misting nozzles connected in parallel or in series through a high-pressure piping or tubing manifold. The mist nozzles ( 6 ) are held in a fixed position by a nozzle support system ( 7 ), which can consist of, but is not limited to, the nozzle manifold ( 5 ) itself, suction cups (not shown) used in conjunction with a wall or other smooth surface, or a rigid structure that the mist nozzles ( 6 ) attach to. As shown in FIGS. 2 and 3 , the preferable rigid nozzle support system ( 7 ) design made from plastic pipe in the preferred embodiment allows for collapsing for easier packaging and storage.
The drain valve ( 8 ) is not an essential component of the device ( 1 ) because it is not needed for proper functioning of the device ( 1 ) but the addition of this drain valve ( 8 ) allows for easier drainage, cleaning, and drying out of the device ( 1 ). The drain valve ( 8 ) can be a separate component connected to the pressure vessel ( 3 ) through high-pressure pipe or tubing, or it can be directly connected or integral to the pressure vessel ( 3 ). A handle ( 12 ) may also be added for easy carriage when the device ( 1 ) is in the collapsed position as shown in FIG. 2 .
For operation of the device ( 1 ), the pressure vessel ( 3 ) is first filled with a fluid to be misted via a fluid fill ( 11 ) opening and through the fill valve ( 4 ), which is closed after filling. Preferably one pre-measured application of mistable fluid is entered into the pressure vessel ( 3 ) via the fluid fill ( 11 ) and through the fill valve ( 4 ). A gas cartridge ( 9 ) is then connected to the gas release valve ( 2 ) and fluidly connected to the pressure vessel ( 3 ). When the gas cartridge ( 9 ) is opened by the gas release valve ( 2 ), preferably by the user pressing the actuation device ( 10 ) such as a foot pedal, the high-pressure gas from the gas cartridge ( 9 ) pressurizes the fluid in the pressure vessel ( 3 ), such that the fluid is then forced out through the manifold ( 5 ) and through the mist nozzles ( 6 ) allowing for a one time use of the device ( 1 ). Depending on the applied use of the device ( 1 ), the operator typically stands in front of the mist nozzles ( 6 ) and slowly rotates to apply the mist to their skin. This procedure is repeated for each subsequent use of the device ( 1 ).
Since certain changes may be made in the above described misting device without departing from the scope of the invention herein involved, it is intended that all matter contained in the description thereof or shown in the accompanying figures shall be interpreted as illustrative and not in a limiting sense. | This disclosure describes a high-pressure gas powered full body self misting device that allows a person to spray a mist onto their whole body at once without using electricity, and without having to hold anything in their hand, such as a can or misting spray wand. This device can be used as a simple, do-it-yourself, misting system for fluids that are commonly applied to or around the body including, but not limited to, tanning solution, skin lotions, and aromatherapy mist. | 1 |
FIELD OF THE INVENTION
The invention relates to a split-inner-ring ball bearing having improved means for providing lubrication and cooling of the internal portions thereof, wherein the split inner ring (inner race) is provided with manifold chambers, grooves and bores interconnected for transmitting lubricant in a proportioned manner to several different internal locations in the ball bearing from a single remote supply source of the lubricant.
Antifriction rolling-element bearings have been known for a long time and many different designs are known. However, without proper lubrication and cooling during operation, the useful life of the bearings is considerably reduced.
Conventional methods of supplying lubricant to the rolling contact surfaces of a bearing by jets work well for low and medium speed bearing applications. At high operating speeds, however, bearings perform better when the lubricant is introduced through passages within the bearing rings, such as through the split of a split-inner-ring ball bearing.
Due to churning effects, the power demand of a high speed bearing increases when the flow of lubricant into the bearing is increased. It may, therefore, be desirable or necessary to introduce only a limited amount of oil into the bearing cavities while the balance of the available lubricant is used to cool the exterior bearing surfaces (the I.D. of the inner ring and the O.D. of the outer ring) to carry off the heat generated within the bearing.
This invention provides improved structure for effecting lubrication and ring cooling of a split-inner-ring ball bearing. It provides means for feeding proportioned amounts of lubricant from a single source thereof to several different locations in the bearing without using restricting orifices in the lubricant flow paths.
Prior designs of split-inner-ring ball bearings incorporating means for lubricating the internal parts of the bearings are not completely satisfactory due to the inability to supply defined amounts of lubricant to various internal parts of the bearings without providing a multitude of lubricant supply sources or providing restricting orifices which are prone to become plugged during use, thereby leading to failure of the bearing.
Accordingly, the objects of the invention are:
to provide a split-inner-ring ball bearing in which the split inner ring has internal passageways effective to divert controlled amounts of lubricant from a single external source to several different internal parts of the bearing, such as the ball members and the retainer contact surfaces thereof, for lubricating and cooling such internal parts, and for cooling the bearing inner ring surfaces, and
to provide a split-inner-ring ball bearing, as aforesaid, in which the proportioning of the lubricant flow is effected without using restricting orifices in the passageways.
Other objects and purposes of the invention will be apparent to persons skilled in the art upon reading the following specification and inspecting the accompanying drawings.
DESCRIPTION OF PRIOR ART
It has been conventional to supply lubricant to the internal parts of split-inner-ring ball bearings. FIGS. 1 to 4 illustrate prior art split-inner-ring ball bearings incorporating lubricant supply means. FIG. 1 shows a split inner ring 3 provided with a circumferential annular groove 12 in its inner wall. The groove 12 communicates with a radial passage 11 in the shaft 8. A plurality of circumferentially spaced radial bores 15 extend outwardly from the groove 12 to the inner ball raceway. FIG. 2 shows another split-inner-race ball bearing provided with an annular manifold 9A in the shaft connected by axial grooves 13A to the groove 12A which is connected to passageways 15A to provide lubricant to the inner ball raceway. Only one internal location, i.e., the inner raceway, of the bearing can be lubricated by the designs of FIGS. 1 and 2. FIG. 3 shows a split-inner-ring ball bearing in which the inner wall of the split inner ring is provided with axially spaced-apart annular manifolds 12B, 12B-1 and 12B-2 communicating with radial passageways 14B, 15B and 16B, respectively, which extend to the internal parts, i.e., the retainer contact surfaces and the inner raceway, of the bearing for supplying lubricant thereto. However, separate individual external lubricant supply means 11B, 11B-1 and 11B-2 are required to communicate with the manifolds 12B, 12B-1 and 12B-2, respectively, to supply the internal moving parts of the bearing with the desired amounts of lubricant. FIG. 4 shows another split-inner-ring ball bearing having a central annular manifold 12C connected with the passageways 14C, 15C and 16C to the internal parts of the bearing to provide lubricant to said parts. However, the flow cannot reliably be proportioned except by restricting the passageways, which is not desirable.
U.S. Pat. Nos. 3,528,711, 3,243,243 and 3,269,786 disclose ball bearings provided with means for supplying lubricant through the inner race thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a sectional view of a prior art ball bearing embodying a first embodiment of lubrication means;
FIG. 2 is a sectional view of another prior art ball bearing embodying a second embodiment of lubrication means;
FIG. 3 is a sectional view of yet another prior art ball bearing embodying a third embodiment of lubrication means;
FIG. 4 is a sectional view of still another prior art ball bearing embodying a fourth embodiment lubrication means;
FIG. 5 is a sectional view of a split-inner-ring ball bearing embodying a first embodiment of the invention;
FIG. 6 is a sectional view of a split-inner-ring ball bearing embodying a second embodiment of the invention;
FIG. 7 is an end view of one ring of the split inner ring of the ball bearing of FIG. 6; and
FIG. 8 is an end view of the other ring of the split inner ring of the ball bearing of FIG. 6.
DESCRIPTION OF PREFERRED EMBODIMENT
Referring now to the drawings, preferred embodiments of the invention are shown in FIGS. 5-8. The embodiment of FIG. 5 is similar to the embodiment of FIGS. 6-8, except that the passageways 34 and 36 of FIGS. 6-8 are omitted in the embodiment of FIG. 5, the grooves 37 extend axially in FIG. 5 and radially in FIG. 6 and the passageway 31 extends radially in FIG. 5 and axially in FIG. 6. Accordingly, the following description will proceed with reference to both embodiments and the same reference numerals will be applied to the same parts in both embodiments.
The ball bearing has an outer ring 21 surrounding a ball retainer 22 which in turn surrounds a split inner ring 23. The split inner ring 23 consists of two rings 23A and 23B, respectively, whose adjacent axial end surfaces abut against each other in a manner well known to those skilled in the art. The outer and inner rings 21 and 23 are provided with raceways 24 and 26, respectively, for receiving bearing balls 27 in a conventional manner. The bearing is mounted on the shaft 28 in any conventional way, for example, by holding the inner ring 23 between the shoulder 29 on the shaft and the locknut 30 as shown in FIG. 5.
The shaft 28 is provided with a passage 31 which communicates at one end with a lubricant supply reservoir or scoop (not shown) and which communicates at the other end with an annular manifold 32 which is formed at the interface between the shaft and one axial end of the split inner race 23. A plurality of circumferentially spaced-apart, axially extending grooves 33A are formed in the radially inner surface of the ring 23A and extend between the axial ends thereof. The ring 23B of the inner race 23 has a plurality of circumferentially spaced-apart, axially extending grooves 33B in its radial inner surface. An annular chamber 38 is formed in the inner axial end surface of the ring 23B adjacent the radially inner side thereof. The chamber 38 communicates with the inner axial ends of the grooves 33A in the ring 23A. The grooves 33B extend from the chamber 38 to the outer axial end of ring 23. The annular chamber 38 is provided so that the axial grooves 33A and 33B need not be in angular alignment for proper functioning of the lubrication structure, according to the invention. The grooves 33B have a greater radial depth than the grooves 33A and, if desired, the radial depth of grooves 33A and/or 33B can progressively increase towards the axial outer end of the ring 23B.
In the embodiment of FIGS. 6-8 only, a plurality of radially extending passageways 34 and a plurality of radially extending passageways 36 extend from grooves 33A and 33B, respectively, and to the radially outer surfaces of the rings 23A and 23B, for supplying lubricant to the inner surfaces of the retainer 22 on opposite sides of the bearing balls.
In both the embodiment of FIG. 5 and the embodiment of FIGS. 6-8, a plurality of axially inclined outwardly extending passageways 35 extend from other ones of the grooves 33A and communicate at their outer ends with radial recesses 39. The recesses 39 are formed in the inner axial end surface of ring 23 and extend to the raceway 26 of the inner ring 23 as shown in FIGS. 5, 6 and 7. The locknut 30 is provided with grooves 37 to allow excess lubricant to escape and return to the lubricant supply reservoir or to lubricate adjacent machine elements.
The rings 23A and 23B can be designed to have any suitable number of axial grooves 33A and 33B and passageways 35 (FIGS. 5-8) and passageways 34 and 36 (FIGS. 6-8) in order to supply desired proportioned amounts of lubricant to the ball raceway and the retainer and/or to channel the oil along the exterior bearing surfaces for ring cooling. The number of grooves 33A need not be equal to the number of grooves 33B and usually the number of grooves 33B is less than the number of grooves 33A. The numbers of grooves 33A and 33B are selected to channel desired portions of the supplied lubricant to the internal parts of the bearing. The lubrication and cooling requirements for different internal parts of ball bearings are different. Normally, more lubricant must be supplied to the inner ball race, in comparison with the inner surfaces of the ball retainer. For example, in the illustrated embodiment of the invention there are sixteen grooves 33A and six grooves 33B. In the illustrated embodiment, there are eight equally spaced passageways 35, two passageways 34 which are spaced 180° apart and two passageways 36 which also are spaced 180° apart. It will be noted that each of the passageways 34, 35 and 36 communicates with different ones of the grooves 33A and 33B and the passageways 34, 35 and 36 are of sufficient size for not restricting the lubricant flow assigned to them. The proportioning of the amounts of lubricant supplied to different parts of the bearing is determined principally by the number of axial grooves 33A and 33B, and the number of passageways 34, 35 and 36 that communicate with the respective bearing parts.
It will be noticed that the apparatus does not use restricting orifices for metering lubricant flow. This is advantageous because restricted orifices are vulnerable to plugging, for example, by coaked oil or extraneous contaminants that might be present in the lubricant.
OPERATION
Although the operations of both embodiments of the ball bearing, according to the invention, are believed to be evident from the foregoing description, a detailed discussion of the operation of the preferred embodiment of FIGS. 6-8 of the invention will be given to insure a complete understanding of the invention. In operation, lubricant is supplied through the passage 31 to the annular manifold 32. Due to centrifugal force generated by the rotation of the shaft 28, the lubricant is then pumped from the manifold 32 to each of the grooves 33A and thence flows outwardly from certain ones of the grooves 33A through the passageways 34 and 35, to the retainer 22 and through the recesses 39 to the ball raceway 26. Because passageways 34 and 35 each communicate with different ones of the grooves 33A, which are of about the same size, approximately equal amounts of lubricant will flow through each of the passageways 34 and 35. The total amount of lubricant reaching the leftward side of the retainer and the ball raceway, respectively, can be adjusted by changing the numbers of grooves 33A and passageways 34 and 35, respectively. The lubricant that flows through the grooves 33A that are not connected to passageways 34 or 35, together with any lubricant that is not pumped into passageways 34 and 35 from the grooves 33A connected thereto, is pumped into the annular groove 38 and thence flows through the grooves 33B. The larger depth of the grooves 33B makes it possible to receive the lubricant and facilitates flow of the lubricant through the passageways 36 to the rightward side of the retainer 22 due to the centrifugal force generated by the rotation of shaft 28. Excess lubricant that flows through the grooves 33B that are not connected to passageways 36 and any lubricant that is not pumped into passageways 36 from the grooves 33B connected thereto, cools the inner race 23 of the bearing and escapes through the grooves 37 in the locknut 30. Hence, by selecting the appropriate numbers of grooves 33A and 33B, and passageways 34, 35 and 36 in the rings 23A and 23B, a given oil flow to the bearing can be proportioned for lubricating desired bearing locations and cooling the bearing rings.
The operation of the embodiment of FIG. 5 is similar, except that the passageways 34 and 36 of FIGS. 6-8 and their corresponding functions are omitted.
Although particular preferred embodiments of the invention have been disclosed in detail for illustrative purposes, it will be recognized that variations and modifications of the disclosed apparatus, including the rearrangement of parts, lie within the scope of the present invention. | A split-inner-ring ball bearing construction is provided with means for feeding proportioned amounts of lubricant from a single source thereof to several different locations in the bearing without using restricting orifices in the lubricant flow paths. | 5 |
TECHNICAL FIELD
[0001] The present invention relates to a mobile terminal for participating in a mobile network. In particular, the present invention relates to a configurable mobile terminal being adapted to perform power consumption sensitive cell reselection. The present invention furthermore relates to a corresponding operating method for operating a mobile terminal and a corresponding computer program. The invention furthermore relates to a network entity of a mobile network that supports participation of such a mobile terminal and a corresponding method and a corresponding computer program.
BACKGROUND OF THE INVENTION
[0002] A mobile terminal, such as an user equipment (UE), is usually operated with a battery providing the necessary energy to the mobile terminal. Concerning most mobile terminals, it is generally strived for a long standby time, as a long standby time is one key performance of a mobile terminal. During standby, a mobile terminal usually searches for an appropriate cell of a mobile communication network to camp on and associates itself to such a cell that provides comparatively strong radio signal strengths and that thus guarantees a comparatively good quality of a radio connection to the mobile communication network.
[0003] In this context, publication D. Fiore et al.: “Cell Reselection Parameter Optimization in UMTS”, 2nd international symposium on wireless communication systems, 2005, IEEE, pages 50-53, describes that user equipment shall regularly search for better cell to camp on according to a cell reselection criterion. Such mechanism shall ensure an acceptable quality of the camping cell. The standby time is decreased by frequent cell reselections, as performing a cell reselection causes some energy consumption. Thus, a very reactive cell reselection mechanism, that is to say: comparatively frequent cell reselections, can guarantee an adequate quality of the camping cell at the expensive of standby time. The publication furthermore describes that a mobile terminal being located in two or more mobile network cells overlapping each other compares signal strength values provided by each of the cells and associates itself to the cell that provides the higher signal strength value. In order to avoid ping-pong effects regarding the cell reselection mechanism due to signal strength values varying in a same small value range, the mobile terminal is equipped with a hysteresis control. Accordingly, the mobile terminal remains associated to a cell, as long as the received-signal strength value of a signal provided by the cell does not leave the hysteresis range. The hysteresis range is defined by a preset value of a difference in received-signal strength between an alternative cell and the currently selected cell. It is also described that increasing the hysteresis range always reduces the reselection rate. This reduction would always lead to an increase of standby time of the mobile terminal but would not necessarily lead to a reduced cell quality.
[0004] From EP 1 300 038 a terminal device is known that is configured to select a cell requiring the least amount of energy for transmitting payload data in terms of the radiated power level.
SUMMARY OF THE INVENTION
[0005] It is a technical object of the present invention to provide a mobile terminal, in particular a stationary mobile terminal, for participating in a mobile network, wherein a standby time of the mobile terminal can be further increased. It is also a technical object of the present invention to provide a corresponding operating method for operating a mobile terminal and a corresponding computer program.
[0006] It is furthermore a technical object of the present invention to provide a network entity of a mobile network that is adapted to support power consumption sensitive cell reselection of mobile terminals participating in the mobile network. It is also a technical object of the present invention to provide a corresponding operating method for operating a network entity and a corresponding computer program.
[0007] According to a first aspect of the present invention, the technical object is achieved by a mobile terminal for participating in a mobile network, the mobile terminal being configured to be operated in a normal mode of operation, which involves a transmission of payload data, and in a low-power mode of operation, which does not involve a transmission of payload data, wherein the mobile terminal comprises:
a detector configured to detect presence of a first possible connection to the mobile network and of a second possible connection to the mobile network, the first possible connection being a connection of a first technology and the second possible connection being a connection of a second technology, a selector configured to identify which of the first possible connection and the second possible connection in the low-power mode causes less energy consumption in the mobile terminal than the other due to a difference between the first and second technology, and a controller configured to connect the mobile terminal to the mobile network through that of the possible connections, which is identified by the selector.
[0011] The present invention recognizes that, in the low-power mode, the mobile terminal can be in a situation, where the first possible connection and the second possible connection to the mobile network are present and wherein there are no explicit requirements for selecting one or the other connection, for instance requirements set by a network provider or requirements derived from a comparison of signal strengths/qualities of both connections. Generally spoken, the mobile terminal being in such situation could principally choose either the first possible connection or the second possible connection for connecting to the mobile network.
[0012] In contrast, according to prior art, a cell reselection is only performed autonomously by a mobile terminal in the normal mode, if the new connection has significantly better signal strength/quality. The mobile terminal of present invention, however, enables an autonomous change of the connection by the mobile terminal also in the low-power mode, based on a criterion of reduced energy consumption, which is required according to a respective technology of a given available connection, in the low-power mode by the mobile terminal.
[0013] According to the present invention, therefore, it is suggested that the mobile terminal comprises a selector configured to identify which of the first possible connection of the first technology and the second possible connection of the second technology allows for less energy consumption in the mobile terminal in the low-power mode than the other due to a difference between the first and second technology, and that the controller of the mobile terminal connects the mobile terminal to the mobile network through the identified less-power consuming connection in the low-power mode, unless there are higher-priority requirements for performing a cell reselection, for instance set by the network provider, the operator of the mobile terminal or defined in a relevant mobile communication standard.
[0014] The term “connection” is to be understood as comprising both, packet-switched and circuit-switched communication channels as different embodiments of establishing a connection having the mobile terminal as one end point. The term “possible connection” is to be understood as comprising also the currently active connection as one of a plurality of possible connections, from which the mobile terminal may select.
[0015] In the following, embodiments of the mobile terminal of the first aspect of the present invention are described. Additional features elucidated in the context of different embodiments can be combined with each other to form further embodiments of the mobile terminal of the first aspect of the present invention, as long as they are not explicitly described as forming mutually exclusive alternatives to each other.
[0016] The normal mode is also often called “active mode”. The low-power mode is in one embodiment a sleep mode. In a sleep mode, functional modules for operation of the mobile terminal are active only to minimum extent. All unnecessary components are shut down in a number of stages. However, the mobile device is registered and paging with the mobile network through a base station or a network node similar in function, through a connection.
[0017] It is noted, that the strongest effect of the invention on energy savings is achieved in the sleep mode. Still, some energy can be saved when implementing the invention alternatively in other modes of operation that do not involve a transmission of payload data. In another embodiment, such other modes of operation that do not involve payload data transmission are included with the sleep mode in the low-power mode according to the present invention to further increase its effect. In such embodiments, therefore, the low-power mode according to the present invention comprises different modes of operation, in which no payload data is transmitted between the mobile network and the mobile terminal, for instance the sleep mode and an idle mode. The idle mode is well known in the art. In the idle mode, more functional modules of the mobile terminal are active than in the sleep mode. When registered to a network in an idle mode, paging is carried out by a mobile terminal in order to achieve and maintain synchrony with the network.
[0018] The present invention is applicable to low-power modes that refer to payload transmission of any kind, voice or data. In one embodiment, the mobile device is configured to distinguish modes of operation additionally by the payload data to be transmitted, for instance voice or data. In this embodiment, separate respective normal and low-power modes of operation are provided for different types of payload data transmission. As an illustrative example of the advantageous applicability of the invention, a mobile terminal camping on a cell has to perform certain computing routines according to a relevant standard of the cell. A change to another available cell providing comparable signal strength can be of advantage. The required routines are often associated to technology-specific, which is meant here to include also cell-specific parameters, such as a Discontinuous Reception (DRX) cycle etc. For instance, the 3GPP specification TS25.133 defines requirements for selection towards a higher ranked cell according to signal strength/quality and defines a measurement periodicity based on DRX cycle length for a mobile terminal being served by a UMTS cell. As a matter of consequence, a cell with a shorter DRX cycle leads to a higher measurement activity, whilst larger DRX cycles require less often neighbour cell measurements. In this example, the change of technology of connection in the low-power mode is formed by changing to a connection with a cell that requires less measurement activity due to a longer DRX cycle.
[0019] Alternatively or additionally to a DRX cycle length, also timer values, such as T3212 values (relevant for both UMTS and GSM), and/or Power Class values (relevant for GSM) can be considered when determining the most suited technology with regards to power consumption employed in available cells, that is to say: when identifying, which of the possible connections causes less energy consumption in the mobile terminal than the other(s) in the low-power mode.
[0020] Hence, in dependence of the technology of the currently associated cell, the power consumption in the mobile terminal in the low-power mode can be larger or smaller. Therefore, it is advantageous that the mobile terminal, when in the low-power mode, connects to the mobile network through such of possible connections that allows for less energy consumption in the mobile terminal than the other(s).
[0021] Since the connection to the mobile network identified by the selector causes less energy consumption in the mobile terminal in the low-power mode, the standby time of the mobile terminal can be increased. Thus, the lifetime of a battery driving the mobile terminal can be increased. These technical advantages are significant, as a long standby time is a key performance feature of a mobile terminal. This is especially valid for use of the mobile terminal in a metering application.
[0022] The selection of the connection of the mobile network according to the least-energy consuming technology for the low-power mode is in one embodiment done autonomously by the mobile terminal. The mobile terminal is not necessarily dependent on a mobile network instruction. However, in other embodiments, the mobile terminal is supported by the mobile network in selecting the connection to the mobile network with regards to achieving less power consumption, especially in the case of a cell configuration causing certain required activity or a certain amount of efforts at the mobile device, which as such leads to a higher power consumption. There are activities of the mobile device, which become obvious as required activities only after the mobile device has read an entire broadcast received from the mobile network. Network support can prevent such drawbacks of increased power consumption in these situations.
[0023] It shall be understood that a single term as in the present description and in the claims shall not be construed in a sense that would reduce the applicability of the present invention to a certain mobile communication standard. For instance, the mobile terminal can be a User Equipment that is adapted to participate in a second generation (2G) and/or third generation (3G) mobile communication network. The mobile network can be a 2G, 2.5G, 3G, LTE or any other mobile communication network. The mobile network can thus be any communication network enabling mobile communication via a radio access network. The applicability of the present invention is not only reduced to methods, devices and computer programs implemented/forming or participating in a wide-area-mobile communication network, such as GSM, UMTS or LTE, but the invention can also be applied in a local mobile communication network like PICO cell, WLAN, WPAN, WiFi or similar networks.
[0024] The first technology and the second technology can in alternative embodiments follow the same technology standard or different technology standards. In an example of different technology standards, the first technology may be UMTS, employing WCDMA, and the second technology may be GSM. However, in an example of identical technology standards employed, the first technology and the second technology could both be UMTS, or, more specifically, both be WCDMA, such as WCDMA DRX 9.
[0025] In particular, presence of a possible connection from the mobile terminal to the mobile network means in one embodiment that such connection is available for the mobile terminal.
[0026] The controller of the mobile terminal is not necessarily to be understood as being a microcontroller in a conventional sense, but rather as a unit that is configured to perform necessary actions in order to effect cell reselection, e.g., disconnecting the mobile terminal from the first connection and connecting the mobile terminal to the second connection or, respectively, vice versa. Furthermore, in an embodiment, the controller is configured to effect further settings in the mobile terminal, such that power consumption in the mobile terminal is furthermore reduced. This aspect is addressed in more detail below.
[0027] In a preferred embodiment, the detector is further configured to detect that one of at least two values, namely, a first value indicative of a received-signal strength and associated with the first possible connection and at least a second value indicative of a received-signal strength associated with the at least one second possible connection, lies in a predetermined hysteresis range with respect to the respective other value. To save energy, the selector is in this embodiment preferably configured to be in operation only upon detection of this hysteresis situation, i.e., that at least one of the received-signal strength values is in the hysteresis range with respect to at least one other of the received-signal strength values. Instead of the received-signal strength, other alternative measurable parameters indicative of the current radio conditions in a functionally equivalent manner may be used for defining and detecting the hysteresis range.
[0028] The predetermined hysteresis range can have an absolute value of, e.g., 10 dB. Such hysteresis value is, e.g., appropriate for a network according to a GSM or a UMTS standard, such as a Received Signal Code Power (RSCP) in UMTS. Further relative values are possible.
[0029] In one embodiment, the selector is further configured to additionally consider, once it is in operation, in particular upon detection of the hysteresis situation, a suitability criterion for the possible connections, in addition to the energy-consumption criterion for the low-power mode. In particular, the selector is configured to additionally check the suitability criterion for the possible connections, and, in case the suitability criterion is not fulfilled by a possible connection that in the low-power mode causes less energy consumption in the mobile terminal than the other possible connections due to a difference between the first and second technology, to block the output of an identification of that possible connection. For instance, in case another cell is available for selection and would be identified according to the energy-consumption criterion by the selector, the received signal strength is additionally analysed according to the cell suitability criterion. The cell suitability criterion may for instance require the received signal strength to be above a threshold level. This is typically the case above around −105 dB, i.e., at a signal level of −104 dB or higher. In a variant of this embodiment, the suitability criterion takes into account known distance values of the mobile terminal from respective transmitters serving the possible connections. In this variant, the selector is configured to perform said identifying additionally in dependence of a first distance value and a second distance value, the first distance value indicating a first distance between a current position of the mobile terminal and a first transmitter associated with the first mobile network cell and the second distance value indicating a second distance between the current position of the mobile terminal and a second transmitter associated with the second mobile network cell. This embodiment recognizes that a distance to a transmitter serving a cell can significantly influence transmission power of the mobile terminal and, therefore, total power consumption of the mobile terminal. The longer the distance, the higher is the transmission power. This particular holds true for a WCDMA based network cell. Instead of a distance to a respective transmitter, a distance from the mobile terminal to a center area of the cell, in which an average signal strength is higher compared to an average signal strength in a remaining area in the cell, may be used.
[0030] The mobile terminal can be in situation where the first signal strength value and/or at least one of the second signal strength values fluctuate within the predetermined hysteresis range.
[0031] Within the predetermined hysteresis range, the mobile terminal is not tied to a requirement that defines which of the first possible connection and the second possible connection is to be selected for connecting to the mobile network. Such requirement may be set by a provider of the mobile network or it may be defined in an applicable communication standard, to which the mobile terminal adheres.
[0032] The mobile terminal can be connected to the mobile network through the first possible connection exhibiting the first received-signal strength value. If the mobile terminal detects that a second possible connection is present that currently offers received-signal strength in the predetermined hysteresis range with respect to the current first possible connection, and that this second possible connection allows a lower energy consumption in the mobile terminal than the current first connection, the mobile terminal of the present embodiment changes from the first connection to the second connection.
[0033] Thus, in contrast to a mobile terminal according to the prior art that does not change a current connection upon detecting a received-signal strength value for an alternative second possible connection that lies in a hysteresis range, the present embodiment provides a cell selection rule, according to which the mobile terminal shall operate in such a hysteresis situation. In particular, the mobile terminal of the first aspect of the present invention can change from a current connection offering a signal exhibiting the first received-signal strength value to another connection offering a signal exhibiting the second received-signal strength that lies in the predetermined hysteresis range.
[0034] In an embodiment, the predetermined hysteresis range can be set and stored in the mobile terminal and can also be adjusted during operation of the mobile terminal.
[0035] The first possible connection can be associated with a first mobile network cell and the second possible connection can be associated with a second mobile network cell. In this case, the controller is preferentially further configured to perform a cell reselection by connecting the mobile terminal to the mobile network through the identified possible connection. The mobile terminal thus performs a power consumption sensitive cell reselection for minimizing power/energy consumption in the mobile terminal.
[0036] In an embodiment, the mobile terminal is adapted to select a cell which is weaker in signal strength than its current serving cell, if the new cell in comparison is beneficial with respect to required power consumption within the mobile terminal.
[0037] It shall be understood, that the technology-based cell reselection according to the present invention can for instance be an inter-RAT or an intra-RAT reselection. Concerning UMTS, the following types of technology-based reselections are possible: 3G-3G, for instance between UMTS and another 3G system, FDD (frequency division duplex) to FDD inter-frequency, FDD/TDD (time division duplex) reselection, TDD/FDD reselection, TDD/TDD reselection, cell reselection 3G-2G (e.g. cell reselection to GSM), cell reselection 2G-3G (e.g. cell reselection from GSM).
[0038] Further technology-related variants can be implemented. For instance, a cell reselection may be based on an information, if available, which GSM frequency band is used. This is especially advantageous when a required power consumption per band is known.
[0039] A technology-based selection of the connection is in one embodiment implemented on the basis of an energy-consumption-selective connection to one of a plurality of mobile networks operated by one of a plurality of network providers. The mobile terminal of this embodiment is configured to be operated using one of a plurality of different subscriber identity modules, such as for instance a SIM, USIM, and/or component SIM. Thus the mobile terminal of this embodiment may be implemented in different variants, one providing for holding only one SIM, others for carrying different SIMs in parallel. While the term subscriber identity module is mostly used in the art with reference to a particular technology standard, namely GSM, it is to be understood in the context of the present specification in a merely functional way, that is, without restriction to a particular technology standard, be it GSM, UMTS, LTE or another technology standard.
[0040] The selector of the present embodiment of the mobile terminal is configured to detect, which of a first possible connection that can be established or maintained using a first subscriber identity module and of a second possible connection to a mobile network that can be established or maintained using a second subscriber identity module causes less energy consumption in the mobile terminal, the first possible connection being a connection of a first technology and the second possible connection being a connection of a second technology.
[0041] The present embodiment may be used with advantage in machine-to-machine applications. Many such application devices are fixed installations equipped with a mobile terminal, for instance in the form of a radio module. Many types of mobile terminal have a SIM holder for operating the device with a removable subscriber identity module. Typically a scan for available mobile networks is performed, when the application device is being installed in the field. In this context, the present embodiment has the advantage of providing as an output information on the most energy saving connection to a mobile network in the low-power mode, irrespective of whether a SIM for any of the respective possible connections is currently installed in the mobile device or not. Upon insertion of a respective SIM for the selected connection, the mobile device can be operated under control by the controller in a particularly power-saving low-power mode, in accordance with the present embodiment of the invention.
[0042] In an embodiment of a mobile device that carries different subscriber identity modules in operation, the network scan may be repeated automatically time after time, or upon manual or remote control input, that is, upon reception of a corresponding control signal, for instance via an AT command. For instance, in one application case an electric meter for energy consumption in a household is equipped with a mobile terminal in the form of a radio module having a plurality of subscriber identity modules for different mobile network providers. The mobile terminal of the present exemplary embodiment performs a cell selection similar to that known in the art as “Informal Network Scan”, which comprises a scan of all available networks, preferably without subscriber identify modules, prior to decide which network provide best radio conditions and is therefore recommended to be chosen for the current mobile terminal, but, in contrast to that known feature, selects a cell, based on energy consumption required for the mobile terminal, in accordance with the various aspects of the present invention. The selection may be performed initially upon start up of the mobile terminal, or during further operation after start up, or both.
[0043] An active support from the network, i.e., assistance in handing over the mobile terminal to a connection of a technology or network being better configured for power consumption, is also possible. Such network support could imply that there is some information stored in the network with regard to power saving aspects of the mobile terminal. For instance, for a first type of a mobile terminal, the first possible connection could be beneficial with regard to power saving aspects, whereas for a second type of a mobile terminal, the second possible connection could be beneficial.
[0044] In another embodiment, the mobile terminal is configured to receive network assistance in performing cell reselection towards the best suited cell with respect to power saving by receiving, from the network, signalled or provided information on most influencing factors for power consumption, such as a DRX cycle and a number of neighbour cells to be measured. There are numerous parameters influencing power consumption in the mobile terminal. In an embodiment, the mobile terminal is configured to receive, from the network, cell class information being relevant for power saving. E.g., the cells can be grouped by the network according to the power consumption they cause in the mobile terminal. In an example, cells are classified in one of ten classes, wherein, e.g., class 10 includes cells that cause particular low energy consumption and class 1 includes cells that cause particular high energy consumption. Due to such cell class information, the mobile terminal does not have to determine itself, which of the first or the second possible connection is to be preferred. Such determination could involve complex calculations, as there can be many parameters influencing power consumption.
[0045] In an embodiment, the controller is further configured to perform said connecting, in particular said cell reselection only, if one of the first signal strength value and the second signal strength value lies in the predetermined hysteresis range.
[0046] In this embodiment of the mobile terminal, it is taken into account that in case that the first signal strength value and the second signal strength value are not in the predetermined hysteresis range, there may be provided explicit requirements, for instance defined in a mobile communication standard, that specify how the mobile terminal has to be connected to the mobile network. However, if such explicit requirements are not present, the mobile terminal shall connect to the mobile network such that energy consumption in the mobile terminal is reduced. This aspect has already been addressed above.
[0047] In a preferred embodiment, the mobile terminal further comprise a first receiver configured to receive signalling information sent by a network entity of the mobile network, the signalling information including adjustment information related to a low power consumption configuration of a cell, to which the mobile terminal is currently associated. In this embodiment, the controller is further configured to adjust a connection setting in the mobile terminal for the low-power mode in dependence of the signalling information.
[0048] A network entity can be any element in a cellular network that is responsible or involved in building up a connection with a mobile terminal. In GSM this is typically a base station controller (BSC) or base station transmitter (BST), while in WCDMA it is a NodeB, but it can refer additionally to further entities within the network where information is present concerning neighbour cells of a respective cell and signal strength information preferably received from mobile terminals.
[0049] The aspect of grouping cells of a network or different networks with respect to their impact on power consumption within the mobile terminal was already outlined above. In an embodiment, the mobile terminal is configured to receive this knowledge via information provided in a broadcast of a serving cell. The information may be provided for the serving cell only. Such broadcast information can be limited to neighbour cells neighbouring the current serving cell and/or to especially suited cells that cause very low power consumption within the mobile terminal. Furthermore, the broadcast can be limited such that it only addresses terminals being interested in low power consumption rather than, e.g., fast mobility. The cell class information can be organized such that each cell is associated to a respective power indication value. Such values can be set by a higher network entity, such as by a RNC or, respectively, it can be calculated individually by each NodeB. Furthermore, a cell may comprise special settings for mobile terminals for low power consumption activity at the cost of reduced mobility.
[0050] This embodiment takes into account the recognition that the mobile terminal has a certain degree of freedom of how to be associated to a current cell. For instance, the current cell could define a minimum DRX cycle to which the mobile terminal has to be set. Besides such DRX cycle, a cell could define further parameters and variables that have to be considered by the mobile terminal for being connected to the cell.
[0051] In this embodiment, the mobile terminal receives information from the mobile network of how to be associated to the current cell such that the energy consumption in the mobile terminal is reduced.
[0052] It is preferred that, in the normal mode, the controller is configured to connect the mobile terminal to the mobile network through either the first or the second possible connection, whichever connection provides better radio conditions to the mobile terminal.
[0053] This embodiment has the advantage that the mobile terminal can be operated in two different modes. In the normal mode, the mobile terminal searches for a connection to a cell according to a known cell reselection criterion such that the most suitable radio conditions are ensured. This prior-art cell reselection does not assess the technology employed in the respective possible connection using a criterion of less energy consumption.
[0054] In this normal mode, therefore, the mobile terminal connects to the mobile network through such connection that provides the comparatively best radio conditions. The term radio conditions is used here to comprise one or more measurable parameters that are indicative of the transmission conditions of a communication channel used or to be used by the connection. Such measurable parameters are for instance a signal strength, an error rate of transmission, such as the bit or block error rate (BER), a signal-to-noise ratio, E b /N 0 , i.e., the ratio of energy per bit to noise power spectral density, or any other parameter.
[0055] For instance, the normal mode can be appropriate if the mobile terminal is moving and/or significant amount of data is transferred to the mobile terminal or from the mobile terminal via the mobile network, for instance during a phone call or during a download or upload of data. The normal mode can also be appropriate as a fall-back mode if in the low-power mode no difference in technology is detected. The connection that provides best radio conditions can be the connection that provides lower energy consumption in the mobile terminal, as an amplifier in the mobile terminal can be run at a lower amplification factor. However, it is to be noted that this mere selection according to the best radio conditions is as such known in the art and not considered by the inventors as forming a part of the present invention.
[0056] It is furthermore preferred that the mobile terminal operates in the normal mode, if the first signal strength value and the second signal strength value are not in the predetermined hysteresis range.
[0057] The other mode, the low-power mode, is advantageous, if the mobile terminal is stationary and if only very few data or no data is currently transferred to the mobile terminal or from the mobile terminal to a network entity. In this mode, the mobile terminal reduces its power consumption such that a long standby time is achieved by connecting to the mobile network through either the first or the second possible connection, whichever connection allows for lower energy consumption in the mobile terminal.
[0058] It is preferred that the mobile terminal is configured to be set either to the normal mode or to the low-power mode, in particular through an AT-command.
[0059] For instance, the selector identifies which of the first possible connection and the second possible connection allows for a longer Discontinuous Reception (DRX) Cycle than the other. A longer DRX cycle results in an increase of the total standby time of the mobile terminal. Alternatively or additionally, the selector performs identification of the low-power connection based on said power indication values named above, if available.
[0060] For instance, if the mobile terminal is connected with multiple core network (CN) domains via one node, the selector identifies the domain with the longest DRX cycle.
[0061] In another preferred embodiment, the mobile terminal further comprises a memory configured to store a list, the list naming one or more technology standards, according to which the mobile terminal is capable to operate. In this embodiment, the selector is preferentially configured to identify only such a connection of the first possible connection and the second possible connection that is a connection according to a technology named in the list. For instance, the list names technology standards from GSM DRX 9 down to GSM DRX 2 and from WCDMA DRX 9 down to WCDMA DRX 6, according to which the mobile terminal can operate. In an embodiment, a position of a certain technology standard named in the list identifies a preference of the certain technology standard.
[0062] In particular, the list stored in the memory can further comprise parameter information related to power consumption aspects for the low-power mode of operation of the mobile terminal associated with each technology standard named in the list. In this embodiment, the selector is preferentially configured to perform that identifying based on the parameter information.
[0063] For instance, the list can thus specify, which of the named technology standards allows for the lowest energy consumption in the mobile terminal. This can be implemented by a prioritizing list listing the technology standards in a certain order, for instance in a manner “WCDMA DRX 9 better than GSM DRX 9 better than WCDMA DRX 6” and so forth. In an example, the detector detects GSM DRX 9 as the first possible connection and WCDMA DRX 6 as the second possible connection. The selector consults the list stored in the memory and firstly recognizes that both the technology standard of the first possible connection and the technology standard of the second possible connection are named in the list. Generally spoken, a change from one connection to the other is thus possible. By consulting the list, the selector furthermore detects that GSM DRX 9 is better in terms of power saving aspects than WCDMA DRX 6. Thus, the selector would identify GSM DRX 9 and the controller would connect the mobile terminal through the identified possible connection GSM DRX 9 to the mobile network.
[0064] In a further preferred embodiment, the mobile terminal comprises a second receiver configured to receive a suggestions signal sent by a network entity of the mobile network, the suggestions signal indicating which of the first possible connection and the second possible connection is suggested by a network entity to be identified. In this embodiment, the selector is configured to identify the suggested possible connection.
[0065] Thus, the mobile terminal is supported by the mobile network in finding the best connection in terms of power saving aspects. This network support can be implemented either in addition or alternatively to the above named list stored in the memory of the mobile terminal. E.g., the network may indicate in the list for the serving cell and also for the neighbour cell, to which classification of power saving the respective cell belongs. Furthermore, as an alternative approach, the network only indicates the most favourable cell in its broadcast.
[0066] The first receiver and the second receiver must not be physically separated from each other but can be realized in a common receiver unit of the mobile terminal.
[0067] Considering that each cell reselection consumes additional power, the number of cell reselections performed for saving energy should be restricted to avoid a counterproductive effect on energy consumption. In a preferred embodiment the controller is further configured to change a connection of the mobile terminal to the mobile network to another of the possible connections, which is currently identified by the selector as causing less energy consumption in the mobile terminal in the low-power mode, only if a rate criterion is additionally fulfilled, the rate criterion requiring a rate of changes of the connection within a predetermined time span, during which the mobile terminal is in the low-power mode, to be smaller than a preset maximum rate of changes. In one implementation of this embodiment, the controller is configured to operate a timer on the basis of information on when cell reselection was executed. Operating the timer may comprise storing time information with regard to the last cell reselection. In a variant, operating the timer involves maintaining a list of time information entries, the list covering for example a given number of recent cell reselections including the last one. The list may be maintained following a FIFO (first in first out) scheme. Controlling the operation of the timer in particular may be performed using time information with regard to (only) those cell reselections, which were triggered by an expected improvement in power consumption. These embodiments thus allow avoiding that in fact more power is consumed due to the additional power requirements of frequent cell reselections. Of course, this requires that such cell reselections are identified by the controller.
[0068] The timer may be implemented in any known manner. A simple variant is to store a constant value of time that needs to elapse before a next cell reselection triggered with the aim of reducing power consumption may be executed.
[0069] In a preferred embodiment the controller is configured to take into account how much improvement in terms of power consumption can be achieved by a given option of a cell reselection. At least two approaches are possible for implementing this functionality:
Prospective approach: the amount of additional energy that needs to be invested is either known or estimated. It is calculated how long the cell connection needs to be maintained after the cell reselection until the cell reselection amortized power-wise. This duration is taken as the minimum timer value. Retrospective approach: after a cell reselection is done it is measured, calculated or estimated how much energy is saved since the cell reselection and not sooner as this amount has leveled the additional amount of energy spent for the cell reselection a new cell reselection is allowed.
[0072] According to a second aspect of the present invention, the technical object is achieved by a method of operating a mobile terminal for participating in a mobile network. The mobile terminal must be configured to be operated in a normal mode of operation, which involves a transmission of payload data, and in a low-power mode of operation, which does not involve a transmission of payload data. The method comprises:
detecting presence of a first possible connection to the mobile network and a second possible connection to the mobile network, the first possible connection being a connection of a first technology and the second possible connection being a connection of a second technology, identifying which of the first possible connection and the second possible connection causes less energy consumption in the mobile terminal in its low-power mode of operation than the other due to a difference between the first and second technology, and connecting the mobile terminal to the mobile network through the possible connection identified as causing less energy consumption in the low-power mode.
[0076] Principally, the operating method of the second aspect of the present invention shares the advantages of the mobile terminal of the first aspect of the present invention. In particular, the operating method has preferred embodiments that correspond to embodiments of the mobile terminal described above.
[0077] For instance, in a preferred embodiment, the operating method additionally comprises a step of detecting that one of a first value indicative of a received-signal strength and associated with the first possible connection and of at least one second value indicative of a received-signal strength associated with at least one second possible connection lies in a predetermined hysteresis range with respect to the respective other value indicative of the received-signal strength. It is also preferred that the method comprises a step of performing a cell reselection by connecting the mobile terminal to the mobile network through the identified possible connection.
[0078] The step of identifying can also comprise receiving of a suggestion signal sent by a network entity of the mobile network, the suggestion signal indicating which of the first possible connection and the second possible connection is suggested by the network entity to be identified.
[0079] According to a third aspect of the present invention, the technical object is achieved by a first computer program for operating a mobile terminal, the first computer program comprising computer code means for causing the mobile terminal to carry out the steps of the method of the second aspect of the present invention, when the first computer program is run on a computer controlling the mobile terminal.
[0080] According to a fourth aspect of the present invention, the technical object is achieved by a network entity of a mobile network, the network entity comprising a transmitter configured to send a suggestion signal to a mobile terminal, the suggestion signal identifying to the mobile terminal, which of a possible first connection of a first technology and a possible second connection of a second technology, through each of which the mobile terminal can be connected to the mobile network, causes less energy consumption in the mobile terminal in its low-power mode of operation, which does not involve a transmission of payload data, due to a difference between the first and second technology.
[0081] In the outcome, the network entity of the fourth aspect of the present invention, which can be, for instance, a base station or a network controller, allows a mobile terminal participating in a mobile network to identify one of a multitude of present possible connections to the mobile network that causes lowest energy consumption in the mobile terminal in its low-power mode due to a difference between the first and second technology. Therefore, the transmission of a simple signal can allow a plurality of mobile terminals to reduce their respective energy consumption by selecting the connection of that technology, which implies the lowest energy consumption in the low-power mode.
[0082] The transmitter of the network entity can further be configured to send signalling information, e.g., via dedicated channel or broadcast, to a mobile terminal, the signalling information including adjustment information related to a low-power-consumption configuration of a cell, to which a mobile terminal is currently associated, allowing the mobile terminal to adjust a connection setting for its low-power mode of operation in dependence of the signalling information. It has been described above with respect to the first aspect of the invention that a mobile terminal can be assisted by the network in selecting the low-power connection by receiving certain information from the network, i.e. power indication values. It shall be understood that, in an embodiment, the transmitter and the network entity are configured to generate and send such certain information. For instance, the network entity is configured to group cells in accordance with their associated power indication values for the low-power mode of operation of a mobile terminal.
[0083] It has already been described above, that a mobile terminal situated in a certain cell still has some degree of freedom of how to actually be associated to the cell. The mobile terminal can thus be associated to the cell and operate according to different adjustment settings, wherein each of the different adjustment setting causes a respective energy consumption in the low-power mode. With the signalling information transmitted by the network entity, the mobile terminal is suggested to choose such an adjustment setting that causes lowest energy consumption in the mobile terminal in the low-power mode.
[0084] Therefore, the above described advantages with respect to power saving aspects in a mobile terminal can in particular be achieved by a mobile network system comprising a mobile terminal according to the first aspect of the present invention and a network entity according to the fourth aspect of the present invention.
[0085] In accordance with a fifth aspect of the present invention, the technical object is achieved by a method of operating a network entity, the method comprising the step of:
sending a suggestion signal to a mobile terminal, the suggestion signal indicating to the mobile terminal, which of a first possible connection of a first technology and of a second possible connection of a second technology, through each of which the mobile terminal can be connected to the mobile network, causes less energy consumption in the mobile terminal in its low-power mode that does not involve a transmission of payload data, due to a difference between the first and second technology.
[0087] The operating method of the fifth aspect of the present invention shares the advantages of the network entity of the fourth aspect of the present invention. In particular, it has preferred embodiments that correspond to the preferred embodiments of the network entity described above.
[0088] According to a sixth aspect of the present invention, the technical object is achieved by a second computer program for operating a network entity of a mobile network, the second computer program comprising program code means for causing the network entity to carry out the step of the method of the fifth aspect of the present invention, when the second computer program is run on the computer controlling the network entity.
[0089] The first and the second computer program of the third and the sixth aspect of the present invention may each be stored/distributed on a suitable medium, such as an optical storage medium, or a solid-state medium supplied together with or as part of other hardware, but may each also be distributed in other forms, such as via the Internet or other wired or wireless telecommunications systems.
[0090] In the description above, only a first and a second possible connection have been named. It shall be understood, however, that more than two possible connections to the mobile network can be available for the mobile terminal and that the connection allowing for lowest power consumption in the mobile terminal in its low-power mode can be chosen among this plurality of possible connections.
[0091] The mobile terminal is advantageously a device that is not or only rarely moved and is supposed to operate for a comparatively long time. For instance, the mobile terminal can thus be a battery driven metering application device, such as a gas/water/electricity etc. metering application or a machine-to-machine (M2M) application device, operating at a fixed location and being designed for minimized energy consumption.
BRIEF DESCRIPTION OF THE DRAWINGS
[0092] These and other aspects of the invention will be apparent from and elucidated with reference to the embodiments described hereinafter.
[0093] In the following drawings:
[0094] FIG. 1 : shows schematically and exemplary a representation of a mobile terminal in accordance with the first aspect of the invention and a representation of a network entity in accordance with the third aspect of the invention,
[0095] FIG. 2 : shows exemplary a flow chart illustrating an embodiment of an operating method for a mobile terminal in accordance with the second aspect of the invention, and
[0096] FIG. 3 : shows exemplary a flow chart illustrating an embodiment of an operating method for a network entity in accordance with the fifth aspect of the invention.
DESCRIPTION OF EMBODIMENTS
[0097] FIG. 1 illustrates a typical network situation where a mobile terminal 100 has the possibility to connect to a mobile network via a network entity 200 through at least one of two connections 210 , 220 .
[0098] For connecting to the mobile network, the mobile terminal 100 is equipped with a coupler 110 . It is illustrated that the mobile terminal 100 is located in an overlapping area of two mobile network cells A and B, wherein the first possible connection 210 is associated with the first mobile network cell A and the second possible connection 220 is associated with the second mobile network cell B. The two mobile network cells A and B can be operated by the network entity 200 , which can be, for instance, a base station or a NodeB. The network entity 200 can be one of a plurality of network entities being controlled by a radio network controller (RNC), which is not shown in FIG. 1 . Such RNC could be part of a UTRAN.
[0099] The mobile terminal 100 connects to the mobile network, such that energy consumption in the mobile terminal 100 is reduced within the scope of possible connections. The mobile terminal comprises a detector 120 (DET) that detects presence of the first possible connection 210 and the second possible connection 220 . For instance the first possible connection 210 is a GSM connection and the second possible connection a UMTS connection. However, both possible connections 210 and 220 can also be of the same technology standard, for instance both connections 210 , 220 can be UMTS connections, wherein the first connection 210 is a WCDMA DRX 6 and the second connection 220 a WCDMA DRX 9 connection.
[0100] The detector 120 not only detects that two possible connections 210 , 220 are present, but also that at least one of a first received-signal strength value associated with the first possible connection 210 and a second received-signal strength value associated with the second possible connection 220 lies in a predetermined hysteresis range with respect to the respective other received-signal strength value. The predetermined hysteresis range can be stored in data storage means 122 of the detector 120 . According to prior art, a mobile terminal being associated to a current cell offering a certain signal strength does not change the currently associated cell, as long as the offered signal of an alternative possible connection is within a hysteresis range of the received-signal strength in order to avoid ping-pong effects, that is to say: in order to avoid that a mobile terminal frequently changes its current connection to a mobile network only due to insignificantly enhanced radio conditions, as such frequent changes of a current connection causes high energy consumption.
[0101] The mobile terminal is configured to be operated in a normal mode of operation, which involves a transmission of payload data, and in a low-power mode of operation, which does not involve a transmission of payload data. The normal mode of operation may involve the transmission of payload data in the form of either voice data in a point-to-point circuit-switched connection, or packet data in a packet-switched connection, or both. The low-power mode typically is either the sleep mode (only), or the idle mode (only), but comprises preferably both, the sleep mode and the idle mode. Both modes are as such known in the art and have been discussed to some detail further above.
[0102] In accordance with the first aspect of the invention, the mobile terminal 100 comprises a selector 140 that identifies which of the first possible connection 210 and the second possible connection 220 causes or, respectively, allows for less energy consumption in the mobile terminal than the other in its low-power mode of operation due to a difference in technology. After the selector 140 has identified the “low power consumption” connection, a controller 160 of the mobile terminal 100 connects the mobile terminal to the mobile network through the identified possible connection, that is: either through the connection 210 or through the connection 220 .
[0103] As the first possible connection 210 and the second possible connection 220 can each be associated to a respective mobile network cell, the controller is also configured to perform a cell reselection by connecting a mobile terminal 100 to the mobile network through the identified possible connection.
[0104] Accordingly, the mobile terminal 100 can be associated to the first cell A. The detector 120 detects that the first received-signal strength value provided by the first cell A lies within the predetermined hysteresis range that is stored in data storage means 122 . The detector 120 furthermore detects that the second possible connection 220 through cell B is present and available. The selector 140 is notified about the two possible connections 210 , 220 . It identifies which of the first and the second possible connections 210 , 220 allows for lower energy consumption in the mobile terminal 100 . This identified connection may either be connection 210 or connection 220 . The controller then connects the terminal 100 to the network through the identified connection.
[0105] The mobile terminal can further be equipped with a first receiver 170 (REC-1) that can receive signalling information 172 sent by the network entity 200 of the mobile network. For sending such signal, the network entity 200 comprises a transmitter 230 .
[0106] The signalling information 172 includes information related to low-power consumption configuration of a cell for a low-power mode of operation of the mobile terminal in connection with this cell, to which a mobile terminal is currently associated. The first receiver 170 can transmit such information to the controller 160 , which can adjust a connection setting in the mobile terminal 100 for the low-power mode in dependence of that transmitted information. For instance, the mobile terminal 100 has several possibilities to camp on a mobile network cell, for instance the network cell A or the network cell B. Within in the scope of such camping possibilities, energy consumption in the mobile terminal 100 can vary. Therefore, the network entity 200 sends signalling information 172 to the mobile terminal 100 that allows the mobile terminal 100 to deduct such settings thereof that lead to a reduced energy consumption in the low-power mode of operation of the mobile terminal 100 .
[0107] The mobile terminal 100 can also comprise a second receiver 190 (REC-2) that receives a suggestion signal 192 sent by the network entity 200 of the mobile network. The suggestion signal 192 indicates which of the first possible connection and the second possible connection is suggested by the network entity to be identified. The selector 140 can simply identify the suggested possible connection and in the outcome, the mobile terminal 100 connects itself to the suggested/identified possible connection. Thus, an indication of a cell or a carrier to be selected by the mobile terminal, for instance a low power consuming application, can be signalled by the mobile network.
[0108] Alternatively or additionally, the mobile terminal 100 comprises a memory 180 that stores a list 182 . The list 182 names one or more technology standards, according to which the mobile terminal 100 is capable to operate. If the detector 120 detects that the first possible connection 210 of the first technology standard and the second possible connection 220 of the second technology standard are present, the selector 140 identifies only such connection of the first possible connections 210 and the second possible connection 220 that is a connection according to a technology standard named in the list 182 .
[0109] The list 182 furthermore comprises parameter information related to power consumption aspects for the low-power mode of operation of the mobile terminal, associated with each technology standard named in the list 182 . Such information can be, for instance, decoded in a prioritizing list that stores information like “GSM DRX 9 better than WCDMA DRX 9 better than WCDMA DRX 6”. For instance, if the detector 120 detects that the first possible connection 210 is a WCDMA DRX 6 connection and the second possible connection 220 is a GSM DRX 9 connection, the selector 140 would firstly determine that both technology standards are stored in the list 182 of the memory 180 and would further recognize that the second possible connection 220 is to be preferred (identified), since GSM DRX 9 allows for less energy consumption in the mobile terminal 100 than the WCDMA DRX 6.
[0110] As mentioned, the mobile terminal 100 can operate in the normal mode and in the low-power mode. In the normal mode, the controller connects the mobile terminal 100 to the mobile network through either the first 210 or the second possible connection 220 , whichever connection provides better radio conditions to the mobile terminal 100 . For instance, the mobile terminal 100 operates in the normal mode if the two signal strength values associated with the first possible connection 210 and the second possible 220 , in comparison with each other, are not in the predetermined hysteresis range. Another case for the normal mode can be a situation where the mobile terminal 100 transmits a significant amount of data to the mobile network or, respectively, receives a significant amount of data from the mobile network, for instance during a phone call, a download or an upload. In this case, good radio conditions have to be present in order to ensure safe and fast data transfer.
[0111] In the low-power mode, the controller connects the mobile terminal through the identified (low-power consumption) connection. The low-power mode applies, if the mobile terminal 100 is not involved in a payload data transfer process.
[0112] The mobile terminal 100 can be set to either the normal mode or the low-power mode, in particular through an AT-command.
[0113] In view of the aforesaid, an advantageous application case of the mobile terminal 100 is a metering application device powered by battery. Concerning in particular a metering application, a long standby time is a key performance feature. Such long standby time is achieved by the mobile terminal 100 as it is connected to that connection of a plurality of possible connections that allows for lowest energy consumption in the mobile terminal 100 in the low-power mode. However, low power consumption can certainly also be advantageous for an application being constantly connected to an electric grid.
[0114] It shall be understood that the block diagram representation of the mobile terminal 100 primary serves for an evident description of the terminal 100 . It does not relate to any geometrical or structural relation between components of an actual realization of a mobile terminal in accordance with the invention. E.g., the first receiver 170 and the second receiver 190 can be realized as a common receiver. Controller 160 , detector 120 and selector 140 can be integrated in a common integrated circuit. It is furthermore possible that the selector 140 and the memory 180 are installed in an application device (not shown) and that receivers 170 and 190 , controller 160 , detector 120 , selector 140 and coupler 110 are installed on a radio module (not shown) that is coupled to the application device via an interface and arranged separately from the application device. In such case, figuratively spoken, the controller 160 , integrated in the module, can contain system determination data and can effect cell reselection. The selector coupled to the memory 180 makes the decision, through which connection the mobile terminal is to be connected, and instructs the controller 160 correspondingly via the interface (not shown).
[0115] FIG. 2 exemplary shows a flow chart illustrating an embodiment 400 of an operating method of operating a mobile terminal for participating in a mobile network. For instance, the mobile terminal 100 depicted in FIG. 1 can be operated according to the method 400 depicted in FIG. 2 . The mobile terminal is preferably configured to be operated in a normal mode of operation, which involves a transmission of payload data, and in a low-power mode of operation, which does not involve a transmission of payload data.
[0116] In a first step 410 , a presence of a first possible connection to the mobile network and a second possible connection to the mobile network is detected, the first possible connection being a connection of a first technology and the second possible connection being a connection of a second technology.
[0117] In a second step 420 , it is identified which of the first possible connection and the second possible connection causes less energy consumption in the mobile terminal in its low-power mode of operation than the other due to a difference between the first and second technology. In a third step 430 , the mobile terminal is connected to the mobile network through the identified possible connection.
[0118] In a similar manner, FIG. 3 shows exemplary a flow chart illustrating an embodiment 600 of an operating method of operating a network identity. Such network identity can be the network identity 200 depicted in FIG. 1 that comprises a transmitter 230 .
[0119] The method 600 comprises the step 610 of sending a suggesting signal to a mobile terminal, the suggestion signal identifying to the mobile terminal, which of a possible first connection and a possible second connection, through each of which the mobile terminal can be connected to the mobile network, causes less energy consumption in the mobile terminal in its low-power mode of operation. The mobile terminal can be a mobile terminal like the mobile terminal 100 depicted in FIG. 1 comprising the second receiver 190 for receiving such suggestion signal. | A mobile terminal includes a detector configured to detect presence of a first possible connection to a mobile network and a second possible connection to the mobile network, the first possible connection being a connection of a first technology and the second possible connection being a connection of a second technology. A selector identifies which of the first possible connection and the second possible connection causes less energy consumption in the mobile terminal in its low-power mode of operation, and a controller connects the mobile terminal to the mobile network through the identified possible connection. The disclosure is also directed to a corresponding operating method, a corresponding computer program, and a network entity for supporting a mobile terminal in performing a power consumption sensitive cell reselection. | 8 |
BACKGROUND OF THE INVENTION
The invention relates to a novel polyamino acid-catalyzed process for the enantioselective epoxidation of α,β-unsaturated enones and α,β-unsaturated sulfones under two-phase conditions in the presence of specific cocatalysts.
Chiral, nonracemic epoxides are known as valuable synthons for preparing optically active drugs and materials (for example (a) Bioorg. Med. Chem ., 1999, 7, 2145-2156; and (b) Tetrahedron Lett ., 1999, 40, 5421-5424). These epoxides can be prepared by enantioselective epoxidation of double bonds. In this case, two stereocenters are produced in one synthetic step. It is therefore not surprising that a large number of methods have been developed for the enantioselective epoxidation of double bonds. However, there is still a great need for novel, improved methods for enantioselective epoxidation.
The epoxidation methods limited to the specific substrates in each case include methods for the enantioselective epoxidation of α,β-unsaturated enones.
Thus, for example, the use of chiral, nonracemic alkaloid-based phase-transfer catalysts for the epoxidation of enones is described in Tetrahedron Lett ., 1998, 39, 7563-7566 , Tetrahedron Lett ., 1998, 39, 1599-1602, and Tetrahedron Lett ., 1976, 21, 1831-1834.
Tetrahedron Lett ., 1998, 39, 7353-7356 , Tetrahedron Lett ., 1998, 39, 7321-7322, and Angew. Chem., Int. Ed. Enql ., 1997, 36, 410-412 furthermore describe possibilities for the metal-catalyzed asymmetric epoxidation of enones using organic hydroperoxides.
WO-A 99/52886 further describes the possibility of enantioselective epoxidation of enones in the presence of catalysts based on sugars. Another method for epoxidation using Zn organyls and oxygen in the presence of an ephedrine derivative has been published in Liebigs Ann./Recueil , 1997, 1101-1113.
Angew. Chem., Int. Ed. Enql ., 1980, 19, 929-930 , Tetrahedron , 1984, 40, 5207-5211, and J. Chem. Soc., Perkin Trans . 1, 1982, 1317-24 describe what is known as the classical three-phase Juliá epoxidation method. In this method, the enantioselective epoxidation of α,β-unsaturated enones is carried out with the addition of enantiomer- and diastereomer-enriched polyamino acids in the presence of aqueous hydrogen peroxide and NaOH solution and of an aromatic or halogenated hydrocarbon as solvent. Further developments of these so-called three-phase conditions are to be found in Org. Synth.; Mod. Trends, Proc. IUPAC Symp . 6 th ., 1986, 275. The method is now generally referred to as the Juliá-Colonna epoxidation.
According to EP-A 403,252, it is possible also to employ aliphatic hydrocarbons advantageously in this Juliá-Colonna epoxidation in place of the original solvents.
According to WO-A 96/33183 it is furthermore possible in the presence of the phase-transfer catalyst Aliquat® 336 ([(CH 3 )(C 8 H 17 ) 3 N + ]Cl − ) and using at the same time sodium perborate, which is of low solubility in water, instead of hydrogen peroxide, for the required amount of base (NaOH) to be reduced, compared with the original conditions of Juliá and Colonna ( Tetrahedron , 1984, 40, 5207-5211), from about 3.7 to 1 equivalent.
Despite these improvements, the three-phase conditions have distinct disadvantages. The reaction times under the original conditions are in the region of days even for reactive substrates. For example, 1-6 days are required for trans-chalcone, depending on the polyamino acid used ( Tetrahedron , 1984, 40 5207-5211). A preactivation of the polyamino acid carried out in the reaction vessel, by stirring in the solvent with the addition of NaOH solution for 12 to 48 hours, shortens the reaction time for many substrates to 1 to 3 days. In this case, no intermediate workup of the catalyst is necessary (EP-A 403,252). The preactivation can be reduced to a minimum of 6 h in the presence of the NaOH/hydrogen peroxide system ( J. Chem. Soc., Perkin Trans . 1, 1995, 1467-1468).
Despite this improvement, the three-phase method cannot be applied to substrates which are sensitive to hydroxide ions ( J. Chem. Soc., Perkin Trans . 1, 1997, 3501-3507). A further disadvantage of these classical conditions is that the polyamino acid forms a gel during the reaction (or even during the preactivation). This restricts the required mixing during the reaction and impedes the working up of the reaction mixture.
Tetrahedron Lett ., 2001, 42, 3741-43 discloses that under the three-phase conditions the addition of the phase-transfer catalyst (PTC) Aliquat 336 in the epoxidation of phenyl-E-styryl sulfone leads to only a slow reaction rate (reaction time: 4 days) and a poor enantiomeric excess (21% ee). To date, no example of the use of PTCs for the epoxidation of α,β-unsaturated enones under the classical three-phase Juliá-Colonna conditions has been disclosed.
The Juliá-Colonna epoxidation has been improved further by a change in the reaction procedure. According to Chem. Commun ., 1997, 739-740, (pseudo)-anhydrous reaction conditions can be implemented by using THF, 1,2 dimethoxyethane, tert-butyl methyl ether, or ethyl acetate as solvent, a non-nucleophilic base (for example, DBU), and a urea/hydrogen peroxide complex as oxidant. The epoxidation takes place distinctly more quickly under these so-called two-phase reaction conditions. According to J. Chem. Soc., Perkin Trans . 1, 1997, 3501-3507, therefore, the enantioselective epoxidation of hydroxide-sensitive enones under the Juliá-Colonna conditions is also possible for the first time in this way.
However, the observation that, on use of the two-phase conditions, the polyamino acid must be preactivated in a separate process in order to achieve rapid reaction times and high enantiomeric excesses proves to be a distinct disadvantage. Several days are needed for this preactivation, which takes place by stirring the polyamino acid in a toluene/NaOH solution. According to Tetrahedron Lett ., 1998, 39, 9297-9300, the required preactivated catalyst is then obtained after a washing and drying procedure. However, the polyamino acid activated in this way forms a paste under the two-phase conditions, which impedes mixing during the reaction and the subsequent workup. According to EP-A 1,006,127, this problem can be solved by adsorbing the activated polyamino acid onto a solid support. Polyamino acids supported on silica gel are referred to as SCAT (silica adsorbed catalysts).
According to EP-A 1,006,111, a further variant of the Juliá-Colonna epoxidation is catalysis of the enantioselective epoxidation by the activated polyamino acid in the presence of water, a water-miscible solvent (for example, 1,2-dimethoxyethane), and sodium percarbonate. However, the use of water-miscible solvents complicates the workup (extraction) in this process.
In the Juliá-Colonna epoxidation, the reaction rate and the enantiomeric excess (ee) that can be achieved depend greatly on the polyamino acid used and the mode of preparation thereof ( Chirality , 1997, 9, 198-202). In order to obtain approximately comparable results, a standard system with poly-L-leucine (pll) as catalyst and trans-chalcone as precursor is used throughout for the development and description of novel methods in the literature. However, besides D- or L-polyleucine, other polyamino acids such as, for example D- or L-neopentylglycine are also used successfully (EP-A 1,006,127).
The object of the present invention was to provide a process that makes the homo-polyamino acid-catalyzed enantioselective epoxidation of α,β-unsaturated enones and α,β-unsaturated sulfones possible but is not subject to the disadvantages of the above-described variants of the Juliá-Colonna epoxidation. It was intended in particular to find a rapid and broadly applicable method that avoids the separate, time-consuming and complicated preactivation of the polyamino acid. At the same time, it was intended that the process have advantages in relation to the space/time yield, handling, economics, and ecology on the industrial scale.
It has now been found, surprisingly, that the epoxidation of α,β-unsaturated enones and α,β-unsaturated sulfones can be carried out under two-phase conditions in the presence of a polyamino acid, as catalyst, that has not been subjected to previous separate activation when the epoxidation takes place in the presence of a phase-transfer catalyst. This procedure surprisingly makes it possible for the reaction times to be very short with, at the same time, high enantiomeric excesses.
SUMMARY OF THE INVENTION
The invention thus relates to a process for the epoxidation of α,β-unsaturated enones or α,β-unsaturated sulfones in the presence of
(1) an organic solvent,
(2) a base,
(3) an oxidant,
(4) a diastereomer- and enantiomer-enriched homo-polyamino acid as catalyst that has not been separately preactivated, and
(5) a phase-transfer catalyst,
but without addition of water.
DETAILED DESCRIPTION OF THE INVENTION
It is crucial that the process according to the invention be carried out in the presence of a phase-transfer catalyst. Examples that can be used are quaternary ammonium salts, quaternary phosphonium salts, onium compounds, or pyridinium salts.
Phase-transfer catalysts that have proved particularly suitable are quaternary ammonium or phosphonium salts of the general formula (I)
(R 1 R 2 R 3 R 4 A) + X − (I)
in which
A is N or P,
X − is an inorganic or organic anion,
R 1 and R 2 are identical or different and are alkyl, aryl, aralkyl, cycloalkyl, or heteroaryl radicals that are optionally substituted by one or more identical or different halogen radicals, and
R 3 and R 4 are identical or different and are alkyl, aryl, aralkyl, cycloalkyl, or heteroaryl radicals that are optionally substituted by one or more identical or different halogen radicals, or R 3 and R 4 together form a C 4 -C 6 -cycloalkyl ring with A.
Phase-transfer catalysts of the general formula (I) that have proved suitable are those in which A and X − have the above-mentioned meanings, and R 1 , R 2 , R 3 , and R 4 are identical or different and are C 1 -C 18 -alkyl, C 6 -C 18 -aryl, C 7 -C 19 -aralkyl, C 5 -C 7 -cycloalkyl, or C 3 -C 18 -heteroaryl.
Particularly suitable phase-transfer catalysts are ((C 4 H 9 ) 4 N) + Hal − (particularly ((C 4 H 9 ) 4 N) + Br − ), ((C 4 H 9 ) 4 P) + Hal − (particularly ((C 4 H 9 ) 4 P) 30 Br − ), ((C 4 H 9 ) 4 N) + HSO 4 − , ((C 8 H 17 ) 4 N) + Br − , [(CH 3 )(C 8 H 17 ) 3 N + ]Cl − , and [(CH 3 )(C 4 H 9 ) 3 N + ]Cl − .
X − in the general formula (I) is an inorganic or organic cation, preferably F − , Cl − , Br − , I − , OH − , HSO 4 − , SO 4 − , NO 3 − , CH 3 COO − , CF 3 COO − , C 2 H 5 COO − , C 3 H 7 COO − , CF 3 SO 3 − , or C 4 F 9 SO 3 − .
The phase-transfer catalysts to be employed according to the invention are normally commercially available or else can be prepared by methods familiar to the skilled person.
The amount of added phase-transfer catalyst is not critical and is normally in the range 0.1 to 20 mol % (preferably in the range 0.5 to 15 mol %, particularly preferably in the range 0.5 to 11 mol %), in each case based on the α,β-unsaturated enones or α,β-unsaturated sulfone employed. However, it is to be observed with amounts that are even lower than 0.1 mol % that the reaction rate decreases markedly, while the high enantiomeric excess is unchanged.
It is possible to employ as α,β-unsaturated enones or α,β-unsaturated sulfones the compounds of the general formula (II)
in which
X is (C═O) or (SO 2 ), and
R 5 and R 6 are identical or different and are (C 1 -C 18 )-alkyl, (C 2 -C 18 )-alkenyl, (C 2 -C 18 )-alkynyl, (C 3 -C 8 )-cycloalkyl, (C 6 -C 18 )-aryl, (C 7 -C 19 )-aralkyl, (C 1 -C 18 )-heteroaryl or (C 2 -C 19 )-heteroaralkyl, each of which radicals is optionally substituted once or more than once by identical or different radicals R 7 , halogen, NO 2 , NR 7 R 8 , PO 0-3 R 7 R 8 , SO 0-3 R 7 , OR 7 , CO 2 R 7 , CONHR 7 , or COR 7 , and where optionally one or more CH 2 groups in the radicals R 5 and R 6 are replaced by O, SO 0-2 , NR 7 , or PO 0-2 R 7 ,
where R 7 and R 8 are identical or different and are H, (C 1 -C 18 )-alkyl, (C 2 -C 18 )-alkenyl, (C 2 -C 18 )-alkynyl, (C 3 -C 8 )-cycloalkyl, (C 6 -C 18 )-aryl, (C 1 -C 18 )-heteroaryl, (C 1 -C 8 )-alkyl-(C 6 -C 8 )-aryl, (C 1 -C 8 )-alkyl-(C 1 -C 19 )-heteroaryl, or (C 1 -C 8 )-alkyl-(C 3 -C 8 )-cycloalkyl, each of which radicals R 7 and R 8 is optionally substituted once or more than once by identical or different halogen radicals.
A (C 1 -C 18 )-alkyl radical means for the purpose of the invention a radical that has 1 to 18 saturated carbon atoms and that may have branches anywhere. It is possible to include in this group in particular the radicals methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, pentyl, and hexyl.
A (C 2 -C 18 )-alkenyl radical has the features mentioned for the (C 1 -C 18 )-alkyl radical, with the necessity for at least one carbon-carbon double bond to be present within the radical.
A (C 2 -C 18 )-alkynyl radical has the features mentioned for the (C 1 -C 18 )-alkyl radical, with the necessity for at least one carbon-carbon triple bond to be present within the radical.
A (C 3 -C 8 )-cycloalkyl radical means a cyclic alkyl radical having 3 to 8 carbon atoms and, where appropriate, a branch anywhere. Included are, particularly, radicals such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and cycloheptyl. One or more double bonds may be present in this radical.
A (C 6 -C 18 )-aryl radical means an aromatic radical having 6 to 18 carbon atoms. Included are, particularly, radicals such as phenyl, naphthyl, anthryl, and phenanthryl.
A (C 7 -C 19 )-aralkyl radical means a (C 6 -C 18 )-aryl radical linked via a (C 1 -C 8 )-alkyl radical to the molecule.
A (C 1 -C 18 )-heteroaryl radical designates for the purpose of the invention a five-, six-, or seven-membered aromatic ring system that has 1 to 18 carbon atoms and that has one or more heteroatoms (preferably N, O, or S) in the ring. These heteroaryl radicals include, for example, 2- or 3-furyl, 1-, 2-, and 3-pyrrolyl, 2- and 3-thienyl, 2-, 3-, and 4-pyridyl, 2-, 3-, 4-, 5-, 6-, and 7-indolyl, 3-, 4-, and 5-pyrazolyl, 2-, 4-, and 5-imidazolyl, 1-, 3-, 4-, and 5-triazolyl, 1-, 4-, and 5-tetrazolyl, acridinyl, quinolinyl, phen-anthridinyl, 2-, 4-, 5-, and 6-pyrimidinyl, and 4-, 5-, 6-, and 7-(1-aza)-indolizinyl.
A (C 2 -C 19 )-heteroaralkyl radical means a heteroaromatic system corresponding to the (C 7 -C 19 )-aralkyl radical.
Halogen or Hal means in the context of this invention fluorine, chlorine, bromine, and iodine.
The substrates preferably employed in the process according to the invention are preferably ax,p-unsaturated enones or α,β-unsaturated sulfones of the general formula (II) in which R 5 and R 6 are identical or different and are (C 1 -C 12 )-alkyl, (C 2 -C 12 )-alkenyl, (C 2 -C 12 )-alkynyl, (C 5 -C 8 )-cycloalkyl, (C 6 -C 12 )-aryl, or (C 1 -C 12 )-heteroaryl, each of which radicals is optionally substituted once or more than once by identical or different radicals R 7 , halogen, NO 2 , NR 7 R 8 , PO 0-3 R 7 R 8 , or OR 7 , and R 7 and R 8 have the meanings indicated above for the general formula (II).
Substrates particularly preferably employed in the process according to the invention are α,β-unsaturated enones or α,β-unsaturated sulfones of the general formula (II) in which R 5 and R 6 are identical or different and are (C 1 -C 12 )-alkyl, (C 2 -C 12 )-alkenyl, (C 2 -C 12 )-alkynyl, (C 5 -C 8 )-cycloalkyl, (C 6 -C 12 )-aryl, or (C 1 -C 12 )-heteroaryl, each of which radicals is optionally substituted once or more than once by identical or different radicals R 7 , halogen, NO 2 , NR 7 R 8 , PO 0-3 R 7 R 8 , or OR 7 , and R 7 and R 8 have the meanings indicated above for the general formula (II), with the proviso that at least one of the radicals R 5 or R 6 is a (C 2 -C 12 )-alkenyl, (C 2 -C 12 )-alkynyl, (C 6 -C 12 )-aryl-, or (C 1 -C 12 )-heteroaryl radical.
It is particularly preferred to subject substrates of the general formula (III) to the epoxidation according to the invention:
where
n and m are identical or different and are the numbers 0, 1, 2 or 3,
R 9 and R 10 are identical or different and are NR 7 R 8 , NO 2 , OR 7 , (C 1 -C 12 )-alkyl, (C 2 -C 12 )-alkenyl, (C 2 -C 12 )-alkynyl, (C 5 -C 8 )-cycloalkyl, (C 6 -C 12 )-aryl, or (C 1 -C 12 )-heteroaryl, each of which radicals R 9 and R 10 is optionally substituted once or more than once by identical or different halogen radicals, and
R 7 and R 8 have the meanings mentioned previously for formula (II).
A decisive advantage of the process according to the invention is the fact that homo-polyamino acids that are not preactivated separately are employed as catalysts.
It is possible to use for the process according to the invention a wide variety of diastereomer- and enantiomer-enriched homo-polyamino acids. Preference is given, however, to the use of homo-polyamino acids selected from the group consisting of polyneopentylglycine, polyleucine, polyisoleucine, polyvaline, polyalanine, and polyphenylalanine. The most preferred from this group are polyneopentylglycine and polyleucine.
The chain length of the polyamino acids will be chosen so that, on the one hand, the chiral induction in the reaction is not impaired and, on the other hand, the costs of synthesizing the polyamino acids are not too great. The chain length of the homo-polyamino acids is preferably between 5 and 100 (preferably 7 to 50) amino acids. A chain length of 10 to 40 amino acids is very particularly preferred.
The homo-polyamino acids can be prepared by state of the art methods ( J. Org. Chem ., 1993, 58, 6247 and Chirality , 1997, 9,198-202). The method is to be applied to both optical antipodes of the amino acids. The use of a particular antipode of a polyamino acid correlates with the stereochemistry of the epoxide. That is to say, a poly-L-amino acid leads to the optical antipode of the epoxide that is obtained with a poly-D-amino acid.
The homo-polyamino acids can be either employed as such unchanged in the epoxidation or previously crosslinked with polyfunctional amines or chain-extended by other organic polymers. The crosslinking amines advantageously employed for a crosslinking are diaminoalkanes (preferably 1,3-diaminopropane) or crosslinked hydroxy- or aminopoly-styrene (CLAMPS, commercially available). Suitable polymer enlargers are preferably nucleophiles based on polyethylene glycol or polystyrene. Polyamino acids modified in this way are described in Chem. Commun ., 1998, 1159-1160, and Tetrahedron: Asymmetry , 1997, 8, 3163-3173.
The amount of the homo-polyamino acid employed is not critical and is normally in the range 0.0001 to 40 mol % (preferably in the range 0.001 to 20 mol %, particularly preferably in the range 0.01 to 15 mol %, and especially in the range 1 to 15 mol %), in each case based on the α,β-unsaturated enone or α,β-unsaturated sulfone employed.
It is also possible to employ the homo-polyamino acids in a form bound to a support, which may be advantageous in relation to the recoverability of the catalyst and the increase in the optical and chemical yield.
For this purpose, the homo-polyamino acids are bound by adsorption to an insoluble support material. The insoluble support materials preferably employed are those based on silica or zeolite, such as, for example, molecular sieves, silica gels, Celite® 521, Celite® Hyflo Super Cell, or Wessalith® DayP. Silica gels with defined pore sizes such as, for example, CPC I or CPC II are also advantageous. Further preferred support materials are activated carbon or sugar derivatives such as, for example, nitrocellulose and cellulose.
The ratio of support material to polyamino acid is given by two limits. On the one hand, only a certain number of polyamino acids can be adsorbed on the insoluble support, and on the other hand, there is a decline in chiral induction with less than 10% by weight of polyamino acid relative to the support onwards. The ratio of homo-polyamino acid to support material is preferably in the range from 1:7 to 2:1 parts by weight, particularly preferably in the range from 1:1 to 1:4 parts by weight.
The method for application to a support is described in detail in EP-A 1,006,127, to which express reference is hereby made. For this purpose, initially a mixture of the appropriate homo-polyamino acid and the support material is suspended in an organic solvent such as an ether (for example THF) and then stirred for a prolonged period, preferably up to 48 hours. The solid is then filtered off and dried.
If such supported catalysts are to be employed, then a particularly suitable device for the epoxidation process is one capable of retaining only the catalyst. This device is preferably an enzyme membrane reactor (C. Wandrey in Enzymes as Catalysts in Organic Synthesis; Ed. M. Schneider, Dordrecht Riedel 1986, 263-284). Preference is likewise given to a simple fixed bed reactor such as, for example, a chromatography column.
The oxidants usually employed are hydrogen peroxide complexes with inorganic carbonates, tertiary amines, amino oxides, amides, phosphanes, or phosphane oxides. The urea/hydrogen peroxide complex has proved particularly suitable.
The amount of the oxidant employed may be varied within the wide limits of 1 to 10 equivalents. Surprisingly, furthermore, short reaction times and high enantiomeric excesses can be achieved even with very small amounts of oxidant in the range 1 to 5 equivalents, preferably 1 to 3 equivalents, and particularly 1 to 2 equivalents.
The process according to the invention is carried out in the presence of a base that may be organic or inorganic. However, organic, non-nucleophilic bases are preferably employed, particularly DBU (1,8-diazabicyclo[5.4.0]undec-7-ene), DBN (1,5-diazabicyclo[4.3.0]non-5-ene), or DABCO (1,4-diazabicyclo[2.2.2]octane).
The amount of the base employed may be varied within the wide limits of 0.1 to 10 equivalents. The reaction according to the invention still takes place with short reaction times and high enantiomeric excesses even with amounts of from 0.5 to 5 equivalents, preferably of from 0.8 to 2 equivalents.
The process according to the invention is carried out using an organic solvent Suitable organic solvents are in general ethers (preferably THF, diethyl ether, or tert-butyl methyl ether), esters (preferably ethyl acetate), amides (preferably dimethylformamide), or sulfoxides (preferably dimethyl sulfoxide).
The temperature used in the epoxidation is generally in the range from −10 to +50° C., preferably in the range from 0 to +40° C., and particularly at +10 to +30° C.
In relation to the procedure for the reaction, normally all the components apart from the base are mixed and then the base is added. However, it is also possible to stir the polyamino acid in the presence of the oxidant, of the base, of the solvent, and of the phase-transfer catalyst for 15 min to 2 hours, and thus preactivate it, and then, without intermediate isolation of the preactivated homo-polyamino acid, to add the substrate to be epoxidized.
The two-phase process according to the invention for the enantio-selective epoxidation of α,β-unsaturated enones and α,β-unsaturated sulfones is distinguished by the possibility of using homo-polyamino acids that have not been preactivated separately. It is possible with this process, because of the presence of a phase-transfer catalyst, to dispense with the normally necessary time-consuming (3 to 5 days) and laborious separate preactivation with intermediate isolation. Substantially higher enantiomeric excesses are usually achieved with the process according to the invention.
The following examples further illustrate details for the process of this invention. The invention, which is set forth in the foregoing disclosure, is not to be limited either in spirit or scope by these examples. Those skilled in the art will readily understand that known variations of the conditions of the following procedures can be used. Unless otherwise noted, all temperatures are degrees Celsius and all percentages are percentages by weight.
EXAMPLES
The process for preparing polyamino acids often provides catalysts for the Juliá-Colonna epoxidation which vary widely in catalytic activity ( Chirality , 1997, 9, 198-202). The conversion per unit time and the enantiomeric excess can be compared for a particular substrate only if the same polyamino acid batch is used for the epoxidation reaction. For this reason, direct comparison of new results with results published in the literature is impossible, simply because different catalyst batches are inevitably used. For this reason, a uniform polyleucine batch was used in each of the subsequent examples and comparative examples.
In all the following examples, the conversion and the enantiomeric excess (ee) were determined by methods known from the literature using HPLC on a chiral, nonracemic phase (UV detection).
Examples 1 and 3 and Comparative Examples 2 and 4
Epoxidation of Trans-Chalcone (1) to Epoxychalcone (2) Under Two-Phase and SCAT Conditions
Example 1
2-Phase Conditions with PTC
50 mg of trans-chalcone, 35 mg of urea/hydrogen peroxide complex (UHP, 0.36 mmol, 1.5 equivalents), 8.5 mg of [(C 4 H 9 ) 4 N + ]Br − , and 100 mg of pll that had not been separately preactivated (11 mol %) were mixed and, after suspending in 1.5 ml of anhydrous THF, 55 μl of DBU (1.5 equivalents) were added. The reaction mixture was allowed to react at room temperature with stirring. After a reaction time of 30 minutes, the reaction mixture was filtered and the filtrate was concentrated under reduced pressure.
Comparative Example CE 2
2-Phase Conditions without PTC
50 mg of trans-chalcone, 35 mg of urea/hydrogen peroxide complex (UHP, 0.36 mmol, 1.5 equivalents), and 100 μg of pll that had not been separately preactivated (11 mol %) were mixed and, after suspending with 1.5 ml of anhydrous THF, 55 μl of DBU (1.5 equivalents) were added. The reaction mixture was allowed to react with stirring at room temperature. After a reaction time of 30 min, the reaction mixture was filtered and the filtrate was concentrated under reduced pressure.
Example 3
SCAT Conditions
a) Preparation of SCAT
1 g of pll that had not been separately preactivated and 3.4 g of silica gel 60 (230-400 mesh, Merck) were mixed, suspended in 30 ml of anhydrous THF, and stirred slowly for 48 h with exclusion of light. The suspension was filtered and the residue was washed twice with 10 ml of anhydrous THF each time. The material (SCAT) was dried in vacuo over P 2 O 5 .
b) Epoxidation Under SCAT Conditions with PTC
50 mg of trans-chalcone, 35 mg of urea/hydrogen peroxide complex (UHP, 0.36 mmol, 1.5 equivalents), 8.5 mg of [(C 4 H 9 ) 4 N + ]Br − , and 100 mg of SCAT (11 mol %) were mixed and, after suspending with 1.5 ml of anhydrous THF, 55 μl of DBU (1.5 equivalents) were added. The reaction mixture was allowed to react with stirring at room temperature. After a reaction time of 30 min, the reaction mixture was filtered and concentrated under reduced pressure.
Comparative Example CE 4
SCAT Conditions without PTC
a) Preparation of SCAT
1 g of non-separately preactivated p1l and 3.4 g of silica gel 60 (230-400 mesh, Merck) were mixed, suspended in 30 ml of anhydrous THF, and stirred slowly for 48 h with exclusion of light. The suspension was filtered and the residue was washed twice with 10 ml of anhydrous THF each time. The material (SCAT) was dried in vacuo over P 2 O 5 .
b) Epoxidation under SCAT Conditions Without PTC
50 mg of trans-chalcone, 35 mg of urea/hydrogen peroxide complex (UHP, 0.36 mmol, 1.5 equivalents), and 100 mg of SCAT (11 mol %) were mixed and, after suspending with 1.5 ml of anhydrous THF, 55 μl of DBU (1.5 equivalents) were added. The reaction mixture was allowed to react with stirring at room temperature. After a reaction time of 30 min, the reaction mixture was filtered and concentrated under reduced pressure.
The results of Examples 1 and 3 and of Comparative Examples CE 2 and 4 are compiled in the table below.
TABLE
Reac-
tion
Exam-
time
Conversion
ee
ple
Conditions
PTC
[min]
[%]
[%]
1
according to the
[(C 4 H 9 ) 4 N + ]Br −
30
>99
78
invention
CE 2
2-phase; not
—
30
>99
53
according
to the invention
3
according to the
[(C 4 H 9 ) 4 N + ]Br −
30
>99
92
invention
CE 4
2-phase, SCAT;
—
30
>99
86
not according to
the invention | The invention relates to a novel process that makes it possible to epoxidize α,β-unsaturated enones or α,β-unsaturated sulfones with high conversions and enantiomeric excesses in a two-phase system without addition of water in the presence of an organic solvent, a base, an oxidant, a diastereomer- and enantiomer-enriched homo-polyamino acid that has not been separately preactivated as catalyst, and a specific phase-transfer catalyst as cocatalyst. | 2 |
BACKGROUND OF THE INVENTION
Blasthole drills are large machines used to drill holes for explosives in mining operations. A conventional blasthole drill comprises a frame supported by crawlers for movement over the ground, and a mast supported by the frame for movement between a substantially vertical position and a number of angled or non-vertical positions. The mast defines a drill hole axis. A rotary head moves relative to the mast along the drill hole axis. The rotary head engages the upper end of a drill pipe for rotating the drill pipe and driving the drill pipe into the ground. When drilling a blasthole that is deeper than the height of the mast, more than one section of drill pipe must be used. After the first section of drill pipe is driven into the ground, the rotary head moves back to the top of the mast and another section of drill pipe is connected to the top of the first section. The rotary pipe then drives the second section into the ground. It is not unusual to use four sections of drill pipe. Such a deep blasthole is referred to as a "multi-pass" blasthole.
After drilling a multi-pass blasthole, it can be difficult to break the joint between two pipe sections. A blasthole drill typically includes an automatic breakout wrench for breaking a joint if the rotary head cannot do so. An automatic breakout wrench is disclosed in U.S. Pat. No. 4,128,135. The automatic breakout wrench turns the upper pipe section while the lower pipe section is held by deck wrenches.
A conventional wrench includes a swing arm pivotable relative to the mast between extended and retracted positions. A wrench member pivots relative to the swing arm about the drill hole axis when the swing arm is in the extended position. The wrench member carries dies for gripping the pipe section. Movement of the wrench member relative to the swing arm is guided by two pins which extend from the wrench member and which move in arcuate slots in the swing arm. A clamping jaw pivots relative to the wrench member between a clamping position and a non-clamping position. The jaw carries a die for gripping the pipe section. When the swing arm is in the extended position, movement of the jaw to the clamping position causes the pipe section to be gripped by the dies on the jaw and on the wrench member. Thereafter, pivotal movement of the wrench member relative to the swing arm (the clamping jaw moves with the wrench member) turns the pipe section to break the joint. Pivotal movement of the wrench member is caused by a hydraulic breakout cylinder connected between the swing arm and the wrench member.
SUMMARY OF THE INVENTION
Conventional automatic breakout wrenches have several disadvantages. The wrench member and the clamping jaw are typically arranged such that the force exerted by the breakout cylinder while breaking the joint both reduces the force of the clamping jaw and creates a moment that forces the wrench away from the pipe section. Also, the stroke of the breakout cylinder and the resulting arcuate movement of the wrench member can be insufficient to break some joints. Furthermore, conventional breakout wrenches are not readily adjustable to accommodate different pipe diameters and to allow for pipe wear.
The invention provides an improved automatic breakout wrench that has several advantages over conventional wrenches. The clamping jaw is relocated, on the inside of the pipe, so that the clamping grip is not reduced by the force of the breakout cylinder. The orientation of the breakout cylinder results in the breakout cylinder creating a moment that forces the wrench toward the pipe rather than away from the pipe. Pivotal movement of the wrench member is guided by three pins, rather than the usual two, for increased stability. The wrench member pivots twenty-four degrees, rather than the usual eighteen degrees, for more effective joint breaking. The clamping jaw is pivotally mounted on one of the pins guiding movement of the wrench member, thereby providing a more economical construction. Shims allow adjustment of the dies to compensate for pipe wear and to accommodate different pipe sizes. The shims are secured in a manner so as to be easily inserted and removed.
More particularly, the improved breakout wrench includes a swing arm mounted on the mast for pivotal movement between extend and retracted positions. The swing arm has therein three separate, arcuate slots centered on a pivot axis which is coaxial with the drill hole axis when the swing arm is in its extended position. One slot is spaced farther from the pivot axis than are the other two slots. A swing hydraulic assembly pivots the swing arm between its extended and retracted positions.
The breakout wrench also includes a wrench member having thereon three pins, each of which is received in a respective one of the swing arm slots for guiding pivotal movement of the wrench member about the pivot axis. A clamping jaw is supported by another one of the pins for pivotal movement relative to the wrench member and between clamping and non-clamping positions. The clamping jaw axis is located "inside" the pipe section to improve gripping of the pipe sections during breaking of the joint. The wrench member and the clamping jaw are pivoted relative to the swing arm by a breakout hydraulic assembly connected between the swing arm and the pin farthest from the pivot axis. The breakout hydraulic assembly has a longitudinal axis which extends between the swing arm axis and the pivot axis so that the force of the breakout hydraulic assembly creates a moment biasing the swing arm toward the pipe section.
The pipe section is gripped by two dies mounted on the wrench member and by one die mounted on the clamping jaw. Each die is held in place by upper and lower fasteners. Shims can be inserted behind each die to adjust the position of the die. Each shim has therein an aperture through which the upper fastener extends to hold the shim in place. The bottom of each shim has therein an upwardly extending slot through which the lower fastener extends. The shim is removed by loosening the lower fastener and by removing the upper fastener from the shim aperture. The slot in the shim allows upward movement of the shim relative to the lower fastener, while the lower fastener maintains the position of the shim.
Other features and advantages of the invention will become apparent to those skilled in the art upon review of the following detailed description, claims and drawings.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevational view of a blasthole drill embodying the invention.
FIG. 2 is an enlarged partial side elevational view of the blasthole drill.
FIG. 3 is partial top plan view of the portion of the blasthole drill shown in FIG. 2.
FIG. 4 is a view similar to FIG. 3 showing a pipe section gripped by the breakout wrench prior to turning of the pipe section.
FIG. 5 is a view similar to FIG. 4 showing the breakout wrench after turning of the pipe section.
FIG. 6 is a view similar to FIG. 4 with portions removed for clarity and with the clamping jaw in its non-clamping position.
FIG. 7 is a view taken along line 7--7 in FIG. 4.
FIG. 8 is an enlarged portion of FIG. 4.
FIG. 9 is a view taken along line 9--9 in FIG. 8.
FIG. 10 is an exploded view of the arrangement for mounting one of the dies.
Before one embodiment of the invention is explained in detail, it is to be understood that the invention is not limited in its application to the details of the construction and the arrangements of 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.
DESCRIPTION OF THE PREFERRED EMBODIMENT
A blasthole drill 10 embodying the invention is illustrated in FIG. 1. The blasthole drill 10 comprises a frame 14 supported by crawlers 18 for movement over the ground. A mast 22 is supported by the frame 14 for movement relative thereto about a generally horizontal axis 26 and between a substantially vertical position (shown in FIG. 1) and a number of angled or non-vertical positions (not shown). The mast 22 defines a drill hole axis 30. A rotary head 34 is moveable relative to the mast 22 along the drill hole axis 30. The rotary head 34 is selectively engageable with the upper end of a drill pipe section 38 supported relative to the mast 22. A number of drill pipe sections are supported for movement relative to the mast 22 by a pipe rack 40 (FIGS. 2 and 3). The pipe rack 40 is movable relative to the mast for moving a drill pipe section 38 between an operating position wherein the drill pipe section extends along the drill hole axis 30 and a non-operating position wherein the drill pipe section is spaced from the drill hole axis. A pair of deck wrenches 42 (FIG. 3) are mounted on the bottom plate 46 of the mast 22. As is known in the art, the deck wrenches 42 selectively engage a drill pipe section to facilitate disconnection of two sections. The blasthole drill 10 as thus far described is conventional and will not be described in greater detail.
A suitable pipe rack is disclosed in U.S. Ser. No. 08/270,959, which is incorporated herein by reference. Except as described below, the blasthole drill 10 is identical to the drill disclosed in U.S. Ser. No. 08/270,959.
The blasthole drill 10 also comprises (see FIGS. 2-7) an improved automatic breakout wrench 50. The breakout wrench 50 is operable, as described below, to turn an upper pipe section 38 relative to a lower pipe section 38 held by the deck wrenches 42 to disengage or unthread the pipe sections. For purposes of the following description, it will be assumed that the mast 22 is in its vertical position, so that the drill hole axis 30 and all parallel axes extend vertically. Obviously, the orientation of the axes and other components of the breakout wrench 50 will change if the orientation of the mast 22 changes.
The breakout wrench 50 includes (see FIGS. 3 and 7) a swing arm 54 mounted on the mast 22 for pivotal movement relative thereto about a swing arm axis 58 parallel to the drill hole axis 30. The swing arm 54 includes a cylindrical tube 62 extending along the swing arm axis 58. The tube 62 is supported for pivotal movement relative to the mast 22 by (see FIG. 7) upper and lower mounting brackets 66 and 70 fixed to the mast 22 by suitable means such as bolts 74. The swing arm 54 also includes substantially identical, spaced upper and lower plates 78 and 82 welded or otherwise fixed to the tube 62 for pivotal movement therewith. Each of the swing arm plates 78 and 82 has therein (see FIG. 3) a generally semi-circular recess 86 into which a pipe section 38 on the drill hole axis 30 extends when the swing arm 54 is in its extended position. The spacing of the plates 78 and 82 is maintained by the connection of the plates to the tube 62 and by (see FIGS. 5-7) spacing assemblies 90 connecting the outer ends of the plates. Each spacing assembly 90 includes (see FIGS. 6 and 7) a sleeve-like spacer 94 between the plates 78 and 82, a bolt 98 extending through the plates 78 and 82 and through the spacer 94, and a nut 102 (see FIG. 7) threaded onto the bolt 98. Each of the plates 78 and 82 has therein (see FIGS. 3 and 6) first, second and third arcuate slots 111, 112 and 113, respectively, centered on a pivot axis 116 which is fixed relative to the swing arm 54 and which is parallel to the swing arm axis 58. The slots 111, 112 and 113 are arcuately spaced from each other, i.e., they are not located along a single line extending radially from the pivot axis 116. The first and second slots 111 and 112 are equidistant from the pivot axis 116, i.e., they extend along the same circle centered on the pivot axis 116. The third slot 113 is spaced from the pivot axis 116 a distance substantially greater than the distance the first and second slots 111 and 112 are spaced from the pivot axis 116. In the illustrated construction, the second slot 112 is approximately two and one-half times as far from the pivot axis 116 as the first and second slots 111 and 112. The purpose of the slots is explained below.
The breakout wrench 50 also includes (see FIGS. 3 and 7) a mechanism 120 for pivoting the swing arm 54 relative to the mast 22 and between an extended position shown in FIG. 4 and a retracted position shown in FIG. 3. When the swing arm 54 is in its extended position, the pivot axis 116 is coaxial with the drill hole axis 30. While various suitable mechanisms can be employed, in the illustrated construction, the mechanism 120 includes (see FIG. 4) a swing hydraulic assembly 124 connected between the mast 22 and the swing arm 54. The hydraulic assembly 124 includes a cylinder 128 having its closed end pivotally connected to the mast 22 via a clevis 132 fixed to the mast 22. The hydraulic assembly 124 also includes a piston (not shown) slideably housed in the cylinder 128, and a piston rod 136 having one end fixed to the piston and an opposite end pivotally connected to the swing arm 54. Specifically, the outer end of the piston rod 136 is pivotally connected to an arm 140 which extends radially from the tube 62 and which is fixed to the tube 62 by a suitable means such as welding. As shown in FIG. 7, the arm 140 includes upper and lower plates 144 and 148 fixed to the tube 62. The outer end of the piston rod 136 extends between the plates 144 and 148 and is pivotally connected to the plates by a pin 152.
It should be understood that many other types of mechanisms can be used to pivot the swing arm 54. Suitable alternative mechanisms include, but are not limited to, electric motors and rotary hydraulic motors.
The breakout wrench 50 also includes (see FIGS. 6 and 7) a wrench member 156 supported by the swing arm 54 for pivotal movement relative to the swing arm 54 about the pivot axis 116. The wrench member 156 extends between the swing arm plates 78 and 82 and includes (see FIG. 7) spaced upper and lower plates 158 and 162 respectively located adjacent the swing arm plates 78 and 82. Each of the wrench member plates 158 and 162 has therein (see FIG. 6) a generally semi-cylindrical recess 166 aligned with the recesses 86 in the swing arm plates 78 and 82. First, second and third pins 171, 172 and 173 extend between the plates 158 and 162 and through the first, second and third slots 111, 112 and 113, respectively, of the swing arm plates 78 and 82. Each of the pins 171, 172 and 173 has a diameter slightly less than the width of the associated slot so that each pin can move along the associated slot and thereby guide pivotal movement of the wrench member 156 relative to the swing arm 54. Each of the pins 171, 172 and 173 is surrounded by (see FIGS. 4 and 7) a washer 176 above the swing arm upper plate 78, and the upper end of each of the pins 171, 172 and 173 has therethrough a cotter pin (not shown) above the associated washer. Each of the pins 171, 172 and 173 is surrounded by (see FIG. 7) a washer 176 below the swing arm lower plate 82, and the lower end of each of the pins has therethrough a cotter pin (not shown) below the associated washer.
The breakout wrench 50 also includes (see FIGS. 5 and 7) a mechanism 184 for pivoting the wrench member 156 relative to the swing arm 54 and about the pivot axis 116. The wrench member 156 moves between a starting position (FIGS. 4 and 6) and a breaking position (FIG. 5). Each of the slots 111, 112 and 113 has an arcuate extent of approximately twenty-four degrees so that the wrench member 156 pivots twenty-four degrees between the starting and breaking positions. In the illustrated construction, the mechanism 184 includes a breakout hydraulic assembly 188 located between the swing arm plates 78 and 82 and the wrench member plates 158 and 162 and connected between the swing arm 54 and the wrench member 156. The hydraulic assembly 188 includes a cylinder 192 having its closed end pivotally connected to a pin 196 extending between the swing arm plates 78 and 82. The hydraulic assembly 188 also includes a piston (not shown) slideably housed in the cylinder 192, and a piston rod 200 (see FIG. 5) having one end fixed to the piston and an opposite end pivotally connected to the third pin 173 and thus to the wrench member 156. The cylinder 192 extends along (see FIG. 3) a horizontal axis 204 (i.e., a line in a plane perpendicular to the drill hole axis 30) which intersects the plane 208 including the swing arm axis 58 and the pivot axis 116 at a point between the swing arm axis 58 and the pivot axis 116. The significance of this location of the cylinder axis 204 is that, when the hydraulic assembly 188 is extended as described below to break a joint, the force of the assembly 188 on the swing arm 54 creates a moment biasing the swing arm toward its extended position.
The breakout wrench 50 also includes (see FIG. 6) first and second dies 211 and 212 mounted on the wrench member 156 so as to engage a drill pipe section 38 extending along the drill hole axis 30 when the swing arm 54 is in its extended position, as shown in FIG. 4. The dies 211 and 212 are supported in respective channel-shaped housings 221 and 222 extending between the wrench member plates 158 and 162. The housings 221 and 222 respectively define rectangular recesses 231 and 232 in which the dies 211 and 212 are respectively mounted in a manner described below.
The breakout wrench 50 also includes (see FIGS. 4-6) a clamping jaw 236 supported by the wrench member 156 for pivotal movement relative to the wrench member 156 about a clamping jaw axis 240 (see FIG. 5) parallel to the pivot axis 116. The clamping jaw 236 extends between the wrench member plates 158 and 162. In the illustrated construction, the clamping jaw 236 is an arcuate block of metal having inner and outer ends (lower and upper ends in FIG. 5) and horizontal upper and lower surfaces respectively located adjacent the upper and lower wrench member plates 158 and 162. The clamping jaw 236 has therethrough a cylindrical bore (not shown) through which the first pin 171 extends such that the clamping jaw 236 pivots about the first pin 171. The clamping jaw 236 is located inside the pivot axis 116, i.e., the clamping jaw axis 240 is spaced from the swing arm axis 58 a distance less than the distance between the pivot axis 116 and the swing arm axis 58. In other words, the clamping jaw 236 is located inside a pipe section 38 on the drill hole axis 30 when the swing arm 54 is in the extended position.
The breakout wrench 50 also includes a mechanism 244 for pivoting the clamping jaw 236 relative to the wrench member 156 and about the clamping jaw axis 240. The clamping jaw 236 pivots between a clamping position shown in FIG. 4 and a non-clamping position shown in FIG. 6. In the illustrated construction, the mechanism 244 includes a clamping hydraulic assembly 248 located between the wrench member plates 158 and 162 and connected between the wrench member 156 and the inner end of the clamping jaw 236. The hydraulic assembly 248 includes (see FIG. 5) a cylinder 252 having its closed end pivotally connected to a pin 256 extending between the wrench member plates 158 and 162. The hydraulic assembly 248 also includes a piston (not shown) slideably housed in the cylinder 252, and a piston rod 260 having one end fixed to the piston and an opposite end pivotally connected to the inner end of the clamping jaw 236. More particularly, the inner end of the jaw 236 has thereon spaced upper and lower ears (not shown), and the outer end of the piston rod 260 extends between the ears and is connected thereto by a pin 272 (see FIG. 5).
The breakout wrench 50 also includes a third die 276 (see FIGS. 6 and 8-10) mounted on the clamping jaw 236 so as to engage a drill pipe section 38 extending along the drill hole axis 30 when the swing arm 54 is in its extended position and the clamping jaw 236 is in its clamping position, as shown in FIG. 4. The die 276 is supported in (see FIGS. 8 and 10) a rectangular recess 280 in the clamping jaw 236.
The dies 211, 212 and 276 are mounted in their respective recesses 231, 232 and 280 in the same manner, and only the mounting of the die 276 will be described in detail. The position of the die 276 relative to the clamping jaw 236 is adjustable to allow for pipe wear and for different pipe sizes. The die 276 is mounted on a rectangular block 284 (see FIGS. 8-10) which is in turn mounted on the clamping jaw 236 in a manner described below. As shown in FIGS. 8 and 10, the die 276 has a curved gripping surface 288 (curved to match the pipe section 38) and is otherwise trapezoidal. The inner surface of the block 284 has therein (see FIG. 10) a trapezoidal recess 292 into which the die 276 slides vertically so that, when the die 276 is in the recess 292, the die 276 cannot move horizontally relative to the block 284. It can be appreciated that the die 276 and the recess 292 can have different shapes and still allow vertical movement of the die while preventing horizontal movement.
The die 276 is secured vertically relative to the block 284 and the block 284 is secured to the clamping jaw 236 by (see FIGS. 9 and 10) upper and lower fasteners 296 and 300 extending through the block 284 and into the clamping jaw 236. While various suitable fasteners can be employed, in the illustrated construction the fasteners 296 and 300 are screws or bolts. As shown in FIG. 9, the die 276 is located between the heads of the fasteners 296 and 300 and is thereby secured vertically relative to the block 284 when the fasteners 296 and 300 are threaded into the clamping jaw 236. As shown in FIGS. 8 and 10, shims 304 can be placed between the block 284 and the clamping jaw 236 to adjust the position of the die 276 relative to the clamping jaw 236. As best shown in FIG. 10, each shim 304 has therein an aperture 308 through which the upper fastener 296 extends to hold the shim 304 in place. The bottom or lower end of each shim 304 has therein an upwardly extending slot 312 through which the lower fastener 300 extends. A shim 304 can be removed by unthreading the upper fastener 296 and removing it from the aperture 308 while simply loosening the lower fastener 300, without completely unthreading the lower fastener 300. When the lower fastener 300 is loosened, the slot 312 allows upward movement of the shim 304 relative to the lower fastener 300 so that the shim 304 can be removed from between the block 284 and the clamping jaw 236. Thus, the lower fastener 300 holds the block 284 in place relative to the clamping jaw 236 and also prevents the die 276 from falling downwardly out of the recess 292 while shims 304 are inserted or removed. The dies 211 and 212 are adjustable in the same manner.
The blasthole drill 10 operates as follows. With a bit and stabilizer (not shown) secured by the deck wrenches 42, the pipe rack 40 is actuated to locate a pipe section 38 over the drill hole. The rotary head 34 is then lowered and screwed onto the top joint of the pipe section 38. After this joint is made, the pipe section 38 is released by the pipe rack, the rotary head 34 and attached pipe section 38 are lowered, and the lower end of the pipe section 38 is attached to the stabilizer held by the deck wrenches 42. With this joint connection complete, the deck wrenches 42 retract and the rotary head 34 and pipe section 38 can be further lowered.
To remove a pipe section 38, the joint is brought up to the deck and the lower pipe section 38 is secured with the deck wrenches 42. If the joint cannot be broken loose with the rotary head 34, the breakout wrench 50 is used as follows.
Two switches (not shown) on the operator's console operate the breakout wrench 50. The switches operate a hydraulic control system (not shown) connected to the three cylinders 128, 192 and 252 by hydraulic lines 320 (partially shown in FIG. 4). Any suitable hydraulic control system can be employed. The first switch swings the wrench 50 in and out, i.e., moves the swing arm 54 between its extended and retracted positions. The second switch engages and disengages the wrench 50, i.e., controls the breakout and clamping cylinders 192 and 252.
The operator initially pushes the first switch to extend the hydraulic assembly 124 and move the swing arm 54 to its extended position (see FIG. 4). This causes the dies 211 and 212 to engage the upper pipe section. The operator then pushes the second switch. This causes the clamping hydraulic assembly 248 to move the clamping jaw 236 to its clamping position (see FIG. 4), so that the die 276 engages the upper pipe section. Once the pipe section is clamped and hydraulic pressure has reached the required level, a sequence valve (not shown) shifts the hydraulic pressure to the breakout cylinder 192 so that hydraulic assembly 188 extends and the wrench member 156 moves from its starting position to its breaking position (see FIG. 5), thereby breaking the joint. The wrench member 156 pivots relative to the swing arm 54 until the breakout hydraulic assembly 188 reaches maximum stroke and stops. The operator then pushes the second switch again. This causes the clamping jaw 236 to return to its non-clamping position and causes the wrench member 156 to return to its starting position. This process can be repeated if it is necessary to further unscrew the joint threads. When the breakout wrench 50 is no longer needed, the first switch is pushed to cause the swing arm 54 to return to its extended position.
Various features of the invention are set forth in the following claims. | An automatic breakout wrench with: the clamping jaw located on the inside of the pipe so that the clamping grip is not reduced by the force of the breakout cylinder; the orientation of the breakout cylinder resulting in the breakout cylinder creating a moment that forces the wrench toward the pipe rather than away from the pipe; pivotal movement of the wrench member guided by three pins; the wrench member pivoting twenty-four degrees; the clamping jaw pivotally mounted on one of the pins guiding movement of the wrench member; and shims secured in a manner so as to be easily inserted and removed. | 4 |
FIELD OF THE INVENTION
[0001] The present invention is directed to a method for remediating sensitization in metals, and more particularly, to remediating sensitization in metals by application of ultrasonic impact treatment (UIT).
BACKGROUND OF THE INVENTION
[0002] Sensitized metals are those that when exposed to high temperatures for extended periods have alloying phases precipitate to the grain boundaries of the metal. Precipitation of the alloying phases makes the materials very susceptible to cracking and material failure. Stress corrosion cracking (SCC) refers to the growth of a crack in a susceptible material that is subjected to tensile stress above a threshold value and exposed to either a gaseous or liquid corrosive environment. A non-exhaustive list of examples of materials susceptible to SCC include carbon steels, low alloy steels, high strength steels, all 300-series stainless steels (including Types 304, 304L, 304H, 321, and 347), aluminum alloys from the 5XXX alloy family which may be sensitized, copper alloys and titanium alloys. Examples of corrosive environments include but are not limited to, hydroxides, nitrates, carbonates, bicarbonates, liquid ammonia, carbon monoxide/carbon dioxide/water, aerated water, chloride, sulfide, thiosulfate, polythionate, hydrogen sulfide, and methanol. When cracking or material failure occurs in sensitized metal, wholesale removal and replacement of the sensitized metal are required since there is no effective repair technique.
SUMMARY OF THE INVENTION
[0003] The present invention is directed to the application of UIT to sensitized metals for effectively remediating the effects of metal sensitization or repairing the sensitized metals using conventional welding procedures. According to one aspect of the invention, there is provided a method for treating metal including providing a workpiece including an area of sensitized metal and decreasing tensile stresses in the area of sensitized metal by imparting compressive residual stress in the area of sensitized metal. Compressive residual stress is imparted to the workpiece by applying a multiplicity of shock pulses in the form of ultrasonic energy with an ultrasonic transducer to the area of sensitized metal thereby creating a treatment zone of plastic material in the metal structure. It is believed that the compressive residual stress imparted to the area of sensitized metal acts to slow the rate of enrichment of alloying elements at grain boundaries within the area of sensitized metal, causes intergranular diffusion of alloying elements in the area of sensitized metal, returns a portion of alloying elements in the area of sensitized metal to solution and reduces or eliminates substantially straight intergranular paths through the workpiece to a surface thereof.
[0004] According to another aspect the invention, there is provided a method for treating metal including providing a workpiece including an area of sensitized metal, the area of sensitized metal including a grain structure including a plurality of crystal grains, and modifying the grain structure by arranging a major axis of each grain of a portion of grains of the plurality of grains to be essentially parallel to a surface of the area of sensitized metal. The grain structure is modified as described above by applying a multiplicity of shock pulses to the area of sensitized metal in the form of ultrasonic energy with an ultrasonic transducer in contact with a surface of the workpiece. Modification of the grain structure in this manner is believed to slow the rate of enrichment of alloying elements at grain boundaries within the area of sensitized metal, cause intergranular diffusion of alloying elements in the area of sensitized metal, return a portion of alloying elements in the area of sensitized metal to solution and reduce or eliminates substantially straight intergranular paths through the workpiece to a surface thereof.
[0005] According to another aspect of the invention, there is provided a method for treating metal including providing a workpiece including an area of sensitized metal, replacing a portion of the area of sensitized metal with a replacement metal, and introducing ultrasound wave energy into the workpiece about a junction of the replacement metal with the workpiece. The ultrasound wave energy is introduced in the form of ultrasonic energy with an ultrasonic transducer in contact with a surface of the workpiece. The ultrasonic wave energy is believed to ultrasonically excite the base metal and relax stresses therein thereby making the base metal more susceptible to grain modification produced by the impact of a set of indenters coupled between the metal surface and the ultrasonic transducer. In this way, it is believed that the introduction of the ultrasound compression energy acts to slow the rate of enrichment of alloying elements at grain boundaries within the area of sensitized metal, causes intergranular diffusion of alloying elements in the area of sensitized metal, returns a portion of alloying elements in the area of sensitized metal to solution and reduces or eliminates substantially straight intergranular paths through the workpiece to a surface thereof.
[0006] According to another aspect of the invention, there is provided a workpiece including a sensitized metal portion having a treatment zone, the treatment zone being constructed and arranged by introducing pulses of ultrasonic wave energy into the sensitized metal portion through periodic ultrasonic mechanical impulse impacts. As a result of the introduction of the ultrasonic wave energy through ultrasonic mechanical impulse impacts, a grain structure of the sensitized metal portion, which includes a plurality of crystal grains, is modified so that each grain of a portion of grains of the plurality of grains has a major axis arranged essentially parallel to a surface of the treatment zone. It is believed this modification of the grain structure causes a reduced rate of enrichment of alloying elements at grain boundaries within the workpiece, an improved intergranular diffusion of alloying elements in the workpiece, intergranular diffusion of alloying elements in the area of sensitized metal, and a reduction of substantially straight intergranular paths through the workpiece. Preferably, the workpiece is constructed of a material selected from a group consisting of a carbon steel, a low alloy steel, a high strength steel, a 300-series stainless steel, an aluminum alloy with a magnesium content greater than three weight percent, a copper alloy and a titanium alloy.
[0007] According to another aspect of the invention, there is provided a method for treating metal including providing a metal workpiece including a stress corrosion crack, and introducing pulses of ultrasonic wave energy into the workpiece through periodic ultrasonic mechanical impulse impacts. The pulses of ultrasonic wave energy are introduced into a sensitized portion of the workpiece which contains the stress corrosion crack in order to stabilize the metal surrounding the crack for cutting or grinding. After metal stabilization, the section of the workpiece that contains the stress corrosion crack is removed, and a replacement plate is welded within an opening created by the removal of the section. During welding of the plate to the workpiece, additional pulses of ultrasonic wave energy are introduced into the workpiece through additional periodic ultrasonic mechanical impulse impacts that are applied to the root weld and cap weld passes. Instead of removing a section of the workpiece and replacing it with a metal sheet, the crack may be ground out thus leaving a depression in the workpiece. Thereafter, the depression can be filled in with weld metal and treated with additional UIT.
[0008] According to yet another aspect of the invention, there is provided a method for treating metal including exposing a metal workpiece to a corrosive environment, wherein the workpiece is susceptible to stress corrosion cracking, and introducing pulses of ultrasonic wave energy into the workpiece through periodic ultrasonic mechanical impulse impacts. The ultrasonic wave energy and periodic ultrasonic mechanical impulse impacts are applied to the workpiece in order to stabilize the workpiece metal thereby making it less susceptible to stress corrosion cracking.
DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 is a plan view of a metallic workpiece surface susceptible to sensitization.
[0010] FIG. 2 is a plan view of an metallic workpiece surface that is susceptible to sensitization and exhibiting indeterminate sensitization.
[0011] FIG. 3 is a plan view of a sensitized metallic workpiece surface exhibit sensitization.
[0012] FIG. 4 is a sectional view of a metallic workpiece that is susceptible to sensitization.
[0013] FIG. 5 is a sectional view of a sensitized metallic workpiece that has undergone UIT sensitization remediation in accordance with a preferred embodiment of the present invention.
[0014] FIG. 6 is a plan view of a sensitized metallic workpiece including a stress corrosion crack.
[0015] FIG. 7 is plan view of the sensitized metallic workpiece of FIG. 6 illustrating a UIT treatment zone about a section of the workpiece containing the stress corrosion crack.
[0016] FIG. 8 is a plan view of the sensitized metallic workpiece of FIG. 7 illustrating removal of the section of the workpiece containing the stress corrosion crack.
[0017] FIG. 9 is a perspective view of the sensitized metallic workpiece of FIG. 8 illustrating a replacement metal plate welded thereto.
[0018] FIG. 10 is a plan view of a sensitized metallic workpiece including a stress corrosion crack.
[0019] FIG. 11 is plan view of the sensitized metallic workpiece of FIG. 10 illustrating a UIT treatment zone about the stress corrosion crack.
[0020] FIG. 12 is a plan view of the sensitized metallic workpiece of FIG. 11 illustrating removal of the stress corrosion crack.
[0021] FIG. 13 is a perspective view of the sensitized metallic workpiece of FIG. 8 illustrating a weld pass along a depression formed by removal of the stress corrosion crack.
DETAILED DESCRIPTION OF THE INVENTION
[0022] The present invention is directed to the application of UIT to sensitized metals for effectively remediating the effects of metal sensitization and/or repairing the sensitized metals using conventional and emergent welding methods. As used herein, sensitized metal refers to metal having an alloying element precipitate out of solution and congregate at the metal grain boundaries thereby forming a continuous or solid film of the alloying element along the metal grain boundaries. The film may extend to the surface of the metal. By forming a continuous or solid film, interconnected intergranular pathways are formed along the grain boundaries of the metal.
[0023] An exemplary metal that is susceptible to sensitization is 5456-H116 aluminum. 5XXX aluminum alloys are commonly used in naval ship structures. These alloys provide high strength-to-weight ratios while maintaining good as-welded strength and excellent corrosion resistance. However, alloys like 5XXX aluminum alloys with above 3 wt % magnesium (Mg) are susceptible to thermal instability. At relatively low temperatures (−70° C.) over varying periods of time from a few years to 10-20 years, the Mg in the aluminum diffuses to grain boundary regions. When the local concentration of Mg is high enough, beta phase (Al 3 Mg 2 ) forms in order to lower the stored energy in the material. The beta phase is anodic to the matrix of alloy in seawater and sea air and this potential difference provides the driving force for dissolution of the beta from the grain boundaries causing intergranular corrosion.
[0024] Depicted at FIGS. 1 through 3 are micrographs of 5XXX aluminum workpiece surfaces. FIG. 1 depicts a workpiece surface exhibiting little to no precipitation of beta phase Al 3 Mg 2 along the grain boundaries. In this micrograph, the grain boundaries of the aluminum are visible as disjointed dots across the surface of the workpiece. FIG. 1 is representative of a metal that is not sensitized. FIG. 2 depicts a workpiece surface exhibiting indeterminate aggregating of beta phase Al 3 Mg 2 along the metal grain boundaries. The grain boundaries are more defined than in FIG. 1 and are visible as disjointed dots and disjointed, short lines along the metal grain boundaries. This is the result of migration of the beta phase Al 3 Mg 2 to the grain boundaries making the boundaries more visible than the boundaries in the 5XXX aluminum workpiece of FIG. 1 . However, since the grain boundaries are not visible as continuous or solid lines, indicating only nominal beta phase migration, the 5XXX aluminum workpiece depicted in FIG. 2 is not a sensitized metal. FIG. 3 depicts a workpiece surface exhibiting substantial aggregation of beta phase Al 3 Mg 2 along the 5XXX aluminum workpiece grain boundaries. In this instance, the grain boundaries are visible as series of solid, interconnected lines along the metal grain boundaries. These lines represent a film of beta phase Al 3 Mg 2 at the boundaries and is indicative of a sensitized metal.
[0025] Sensitization of metals is problematic since sensitized metals are susceptible to stress corrosion cracking. Stress corrosion cracking occurs when a material susceptible to stress corrosion, such as a sensitized metal, is exposed to a corrosive environment and tensile stresses are experienced in the material above a threshold value. In a sensitized metal, stress corrosion cracking results from the penetration of corrosive elements of the corrosive environment into the metal along pathways created by intergranular corrosion of the metal along the grain boundaries by the continuous film of precipitated alloying elements. By exposing the internal grain boundary surfaces of the metal to the corrosive elements, the metal is further degraded along the grain boundaries causing further intergranular corrosion and the formation of cracks which are exacerbated by the presence of tensile stresses.
[0026] It has been discovered that by treating sensitized metal with UIT, the susceptibility of the metal to stress corrosion cracking can be reduced or eliminated. It has further been discovered that metals exhibiting a stress corrosion crack can be repaired more efficiently than utilizing present methods if the metal undergoes UIT before, during and after the stress corrosion crack is removed. UIT, as used herein and described in detail in U.S. Pat. Nos. 7,431,779; 7,344,609; 7,301,123; 7,276,824; 6,932,876; 6,843,957; 6,289,736, and 6,171,415, all of which are incorporated herein by reference in their entireties, refers to a process of introducing pulse wave energy in combination with ultrasonic mechanical impulse impacts into a load bearing work body's interior structure in such magnitude as to affect or improve the grain structure and the residual stress patterns therein. In particular, the pulse wave energy and impulse impacts cause compressing of the top layer of the metal body and expanding of the top metallic layer in all directions parallel to the metal's surface. The surface layer expands beyond its elastic limit and experiences plasticity, which means that it experiences a permanent tensile strain. The surrounding elastically deformed material opposes this tensile strain thereby imparting compressive residual stresses in the surface of the metal in directions parallel to the surface. By expanding the top layer of the metal, the corrosive elements of the corrosive environment are prevented access to the internal grain boundaries of the metal. Thus, the corrosive elements cannot penetrate the metal. Further, by imparting compressive residual stresses in the metal, the effects of the tensile stresses can be ameliorated.
[0027] More particularly, depicted at FIGS. 4 and 5 are sectional views of the grain boundaries of two metal workpieces. In FIG. 4 , the represented workpiece has not undergone UIT treatment. In this instance, the crystal grains of the metal have a cuboidal shape or cross-section. The grain boundaries arranged between the cuboidal-shaped crystal grain extend generally vertically and laterally. In a sensitized metal, the vertically-extending grain boundaries present pathways 10 along which stress corrosion cracks can form and exit to the surface of the metal thereby increasing the likelihood of failure of the metal workpiece. In FIG. 5 , the represented workpiece has undergone UIT treatment. In this instance, crystal grains near the surface of the workpiece have been expanded in all directions parallel to the workpiece metal surface. The individual metal grains are transformed from a cuboidal shape to a flattened or pancake shape having major axes that extend parallel to the surface of the workpiece surface. By flattening of the metal crystal grains near the surface of the workpiece in a sensitized metal, the intergranular pathways 12 along which stress corrosion cracking can occur become more convoluted and longer than the intergranular pathways 10 in untreated sensitized metals. The result of this grain structure modification is that subsurface defects in the material lack a clear intergranular path to the surface, thus delaying cracks from propagating to a workpiece surface. Grain modification thereby forces a crack to try and propagate across a grain itself, which is a more difficult path requiring more energy to propagate. Further, when the workpiece is located in a corrosive environment, the rate at which the corrosive elements penetrate through the surface of the metal and into the workpiece is reduced.
[0028] The penetration of the corrosive elements into the workpiece along pathways 12 may further reduced or altogether eliminated utilizing UIT. Microstructural investigation has shown that UIT treatment of metals produces ultrafine grain structure in the nanocrystalline regimen of the metal down to a depth from the surface of about 6-10 μm. This grain refinement process has been suggested to follow formation of high dislocation density and twining structure following further straining, formation of microbands structure, subdivision of microbands structure into submicron grains, and further breakdown of the subgrains to be equiaxed. Thus, UIT treatment of metals can achieve nanocrystallization of the surface layer for the metal, which is believed to improve in the corrosion and fatigue properties of the materials. In the context of UIT treated sensitized metal, it is believed the nanocrystallization of the surface layer for the metal can likely prevent essentially all penetration by corrosive elements into the workpiece.
[0029] In addition to reducing or preventing corrosion element penetration of the metal workpiece and increasing the energy required to propagate a crack within the workpiece, it is believed that UIT treatment of a sensitized metal slows further enrichment of alloying elements at grain boundaries. As explained above, sensitization is a result of enrichment of one or more alloying elements at the grain boundaries. An example are aluminum alloys with magnesium content greater than three weight percent, such as the 5XXX alloy family. The beta phase Al 3 Mg 2 rich in magnesium tends to migrate to the grain boundaries. This results in intergranular corrosion and/or greater susceptibility to external, environmental corrosion factors. Accelerated corrosion may occur along a path of higher than normal corrosion susceptibility, which is the along the grain boundaries of a sensitized material where precipitates have migrated to, with the bulk of the material typically being passive. By imparting compressive residual stresses and stress relaxation with UIT, coupled with engineered repairs, the migration of precipitates to the grain boundaries may be slowed to such an extent that stress corrosion cracking no longer effectively influences the service life of the structures. This may be due in part to stabilization of the metal by the introduction of ultrasonic energy, ultrasonic or impulse relaxation, compressive residual stresses or a combination thereof. UIT is also believed to reverse metal sensitization by causing intergranular diffusion of alloying elements thereby eliminating enrichment of alloying elements at grain boundaries and regenerating the metal. To do so, the energy imparted to the base metal by UIT must be of sufficient magnitude to cause the precipitates to return to solution.
[0030] To impart the requisite pulse wave energy and ultrasonic mechanical impulse impacts to a metal body to obtain the metal grain and metal grain boundary modifications discussed above, an ultrasonic impact operating system as described in U.S. Pat. No. 6,932,876 can be used. That system employs a set of ultrasonically movable impacting elements, presented typically as sets of three or four spaced members, for impacting a metallic work surface under control of an ultrasonic transducer head. A periodic pulse energy source, typically operable at ultrasonic frequencies up to 100 kHz, induces oscillations into the transducer head, preferably subject to feedback frequency and phase control processing feedback from the working transducer head to aid in matching resonance characteristics of the head when working on the work surface in the manner more particularly set forth in the parent applications of U.S. Pat. No. 6,932,876. The impacting element set creates at the work surface and extending into the sub-surface region of a metallic work body, plasticized metal permitting the surface texture to be machined and sub-surface structural modifications in the work body material to be retained, UIT imparts both ultrasonic relaxation and impulse relaxation within the material. These two components of UIT reduce the magnitude of the tensile residual stresses in the material at greater depths than the plasticity induced compressive stresses which are a surface phenomenon. These methods of relaxation or combinations thereof may result in the resultant tensile stress to be below the threshold value that is a pre-requisite for stress corrosion cracking.
[0031] FIGS. 6 though 13 depict two engineering repair methods utilizing UIT on a sensitized metal workpiece including stress corrosion-induced damage. In FIGS. 6 through 9 , the damaged workpiece includes a crack and sufficient metal sensitization around the crack that the crack and a portion of the surrounding workpiece metal must be removed and replaced. In FIGS. 10 through 13 , the damaged workpiece includes a crack with a level of sensitization of the metal around the crack that only the surface of the metal defining the crack is removed and replaced.
[0032] More particularly, referring to FIGS. 6 and 7 , there is depicted a sensitized metal workpiece 16 , such as a 5XXX aluminum alloy workpiece, including a crack 18 created by stress corrosion. According to this method, a treatment zone 20 is produced in workpiece 16 by introducing pulse wave energy and ultrasonic mechanical impulse impacts to workpiece 16 by utilizing the ultrasonic impact operating system discussed above and thereby modifying the metal as described above. Treatment zone 20 is formed around a section 22 of workpiece that includes crack 18 and other metal that is sufficiently sensitized or otherwise damaged metal to require that the metal be removed from the workpiece. By forming treatment zone 20 , the metal therein is stabilized allowing for a cut to be made within the treatment zone and removal of damaged zone 22 from the workpiece without causing additional potentially damaging stresses to the metal.
[0033] Referring to FIGS. 8 and 9 , following pre-treatment of workpiece 16 with UIT, section 22 and, optionally a portion of treatment zone 20 situated adjacent to section 22 , are cut from workpiece 16 thereby forming an opening 24 within workpiece 16 and treatment zone 20 . Opening 20 is covered by placing a replacement metal sheet 26 sheet and butt welding sheet 26 within opening 20 along joint 28 . Following deposition of the root pass weld along joint 28 , UIT is applied along the root pass body and toes to strengthen the weld metal against sensitization and to relax any stress within the metal caused by cutting, fit up and welding. Where multi-pass welds are required, UIT can be applied to the fill passes. A final cap pass UIT application is applied along the cap pass weld of joint 28 . Following UIT application along the weld passes, additional UIT is applied to the weld heat affected areas of replacement metal sheet 26 and workpiece 16 adjacent joint 28 .
[0034] Referring to FIGS. 10 and 11 , there is depicted a sensitized metal workpiece 30 , such as a 5XXX aluminum alloy workpiece, including a crack 32 created by stress corrosion. According to this method, a treatment zone 34 is produced in workpiece 30 by introducing pulse wave energy and ultrasonic mechanical impulse impacts to workpiece 30 by utilizing the ultrasonic impact operating system discussed above and thereby modifying the metal as described above. Treatment zone 32 is formed around crack 32 , including crack 32 , and follows the general shape of crack 32 . By forming treatment zone 32 , the metal therein is stabilized allowing for crack 32 to be removed from the workpiece without causing additional potentially damaging stresses to the metal.
[0035] Referring to FIGS. 12 and 13 , following pre-treatment of workpiece 30 with UIT, crack 32 is removed from workpiece 16 by grinding thereby forming a depression 36 within workpiece 30 and treatment zone 34 . Depression 36 may or may not extend through workpiece 30 . Following removal of crack 32 , a weld material 38 is deposited within depression 36 thereby filling the depression. Following deposition of the root pass weld within depression 36 , UIT is applied along the root pass to strengthen the weld metal against sensitization and to relax any stress within the metal caused by cutting, fit up and welding. A final cap pass UIT application is applied along the cap pass weld of depression 36 . As described above, for FIGS. 6 through 9 , UIT can be applied to the fill passes when multi-pass welds are required. Further, following UIT application along the weld passes, additional UIT is applied to the weld heat affected areas of replacement metal sheet 26 and workpiece 16 adjacent joint 28 .
[0036] As will be apparent to one skilled in the art, various modifications can be made within the scope of the aforesaid description. Such modifications being within the ability of one skilled in the art form a part of the present invention and are embraced by the claims below. | An ultrasonic impact treatment method for remediating metal sensitization including introducing ultrasound compression wave energy through ultrasonic mechanical impulse impacts into an area of sensitized metal in a workpiece. The ultrasound compression wave energy and impulse impacts impart compressive residual stress to the workpiece thereby decreasing tensile stresses in the sensitized metal and modifying the grain structure of the workpiece. These changes to the structure of the workpiece combine to slow the rate of enrichment of alloying elements at grain boundaries within the area of sensitized metal, cause intergranular diffusion of alloying elements in the area of sensitized metal, return a portion of alloying elements in the area of sensitized metal to solution and reduce or eliminate substantially straight intergranular paths through the workpiece. | 2 |
BACKGROUND OF THE INVENTION
This invention relates to translators for digital logic signals; and more particularly, it relates to signal translators which enable conventional CMOS logic gates and conventional BiCMOS logic gates to be interconnected and communicate with each other.
Conventional CMOS logic gates (NAND gates, NOR gates, etc.) operate between 0 and +5 volts. That is, the CMOS transistors which make up the logic gates are interconnected between a +5 volt power bus and a ground bus. Input signals and output signals for the CMOS logic gates have a high level of +5 volts and a low level of 0 volts.
By comparison, conventional bipolar logic gates operate between 0 and -5.2 volts. That is, the bipolar transistors which make up the logic gates are interconnected between a ground bus and a -5.2 volt power bus. Input signals and output signals for the bipolar logic gates have a high level of -0.8 volts and a low level of -1.6 volts.
Due to the differences in the power supply voltages and the input and output signal levels of the conventional CMOS logic gates and the conventional bipolar logic gates, those two types of logic gates cannot be connected directly to each other. To solve this problem in the prior art, the conventional CMOS logic gates have been modified by replacing the ground bus with a -5.2 volt power bus and replacing the +5 volt bus with a ground bus. With this change, the high voltage level from the modified CMOS logic gate becomes 0 volts and the low logic level becomes -5.2 volts. Then, to enable such modified CMOS logic gates to be interconnected to the conventional bipolar logic gates, signal translators have been developed which convert the 0 and -5.2 volt modified CMOS logic signals to the -0.8 volt and -1.6 volt bipolar logic signals. Circuits which include these modified CMOS logic gates, signal translators, and bipolar logic gates are called conventional BiCMOS logic circuits.
Despite the development of the above described BiCMOS logic circuits, conventional CMOS logic gates that operate between 0 and +5 volts are still used in many logic systems. And, to interconnect those conventional CMOS logic gates to the modified CMOS logic gates in BiCMOS circuits would require another type of translator which translates +5 and 0 volt signals to 0 and -5 volt signals (and vice versa). This type of translator has not been provided in the prior art.
Such a translator would have to operate between +5 volts and -5 volts. This is because the input signals go up to +5 volts and the output signals go down to -5 volts (or vice-versa). Consequently, the transistors in the translator would be exposed to a voltage difference of 10 volts; and, that in turn presents the question of how to design the translator such that its transistors do not break down.
Clearly, if the transistors in the translator are made with a high breakdown voltage which exceeds 10 volts, then breakdown will be avoided. However, the transistors which make up the conventional CMOS logic gates and the modified CMOS logic gates normally have a breakdown voltage which exceeds their 5 volt signal swing by only a small margin (e.g. a couple of volts). This small breakdown voltage margin is desired because raising the breakdown voltage of a transistor inherently decreases the speed at which the transistor switches.
Breakdown voltage in a transistor can, for example, be increased by increasing the doping concentration of the transistor's source and drain regions. But that inherently increases the source and drain capacitance, which reduces switching speed. Also, if only the transistors in the signal translator are made with a breakdown voltage which exceeds 10 volts, then special steps would have to be added to the fabrication process that is used to make all the other transistors in the conventional CMOS logic gates and modified CMOS logic gates. But, that in turn would increase the cost of the translator.
Accordingly, a primary object of the invention is to provide a signal translator which converts conventional CMOS signal levels of +5 and 0 volts to modified CMOS signal levels of 0 and -5 volts, and which is constructed of transistors whose breakdown voltage is only a couple of volts larger than 5 volts.
BRIEF SUMMARY OF THE INVENTION
In accordance with the present invention, a signal translator circuit receives a conventional CMOS input signal of +5 and 0 volts and produces a modified CMOS output signal of 0 and -5 volts. This translator circuit includes, a first resistance coupled to a positive supply voltage bus and a second resistance coupled to a negative supply voltage bus. Also included is an P-channel transistor, having a source and drain coupled in series between the first and second resistance and having a gate coupled to a ground bus. Further included is a N-channel transistor having a gate coupled to an input terminal for receiving the input signal, and having a source and drain coupled respectively to the gate and source of the P-channel transistor. Lastly, an output terminal is coupled to the drain of the P-channel transistor on which the output signal is generated.
By properly selecting the source-drain resistances of the N-channel and P-channel transistors relative to the first and second resistances, the breakdown voltage of the transistors can be kept at a small margin (e.g.--two volts) above the supply voltages.
Also, when the P-channel transistor is changed to a N-channel transistor, and the N-channel transistor is changed to a P-channel transistor, the circuit translates modified CMOS signal levels to conventional CMOS signal levels. That is, the circuit translates 0 and -5 volt signals to +5 and 0 volt signals.
BRIEF DESCRIPTION OF THE DRAWINGS
Various preferred embodiments of the invention are described in detail herein in conjunction with the accompanying drawings wherein:
FIG. 1 is a circuit diagram of one embodiment which translates conventional CMOS logic levels to modified CMOS logic levels;
FIG. 2 illustrates the operation of the FIG. 1 embodiment under the condition where the input signal is a high logic level;
FIG. 3 illustrates the operation of the FIG. 1 embodiment under the condition where the input signal is a low logic level;
FIG. 4 shows three sets of equations which explain in greater detail the operation that is illustrated in FIGS. 2 and 3;
FIG. 5 illustrates a second embodiment of the invention which translates modified CMOS logic levels to conventional CMOS levels;
FIG. 6 illustrates the operation of the FIG. 5 embodiment under the condition where the input signal is a low logic level;
FIG. 7 illustrates the operation of the FIG. 5 embodiment under the condition where the input signal is a high logic level; and,
FIG. 8 shows three sets of equations which further explain the operations illustrated in FIGS. 6 and 7.
DETAILED DESCRIPTION
Referring now to FIG. 1, the details of one preferred embodiment of a signal translator circuit 10 that is structured according to the invention will be described. This translator circuit 10 receives digital input signals v i on a lead 11 which are at CMOS voltage levels; and, it translates those signals into digital output signals v o on an output lead 12 which are at BiCMOS voltage levels. A high level for the input signals v i is a positive supply voltage V+; a low level for the input signals v i is ground (zero volts); a high level for the output signals v o is ground; and a low level for the output signals v o is a negative supply voltage V-. One specific example of the supply voltages V+ and V- are +5 volts and -5.2 volts respectively.
As FIG. 1 shows, the signal translator circuit 10 includes four field effect transistors which are labeled T P , T N , T 1 , and T 2 . Those transistors are interconnected between a V+ voltage bus 13, a ground bus 14, and a V- voltage bus 15 as shown. Transistor T P is a P-channel transistor, and the remaining transistors are N-channel transistors. Transistors T N and T P have their source labeled S and their drain labeled D; and, they operate in either an ON state or an OFF state as is described below to achieve the desired voltage translation. By comparison, transistors T 1 and T 2 have their gate connected to their drain, so they merely operate as resistors having respective source-drain resistances R 1 and R 2 .
When the input signal v i is at a high voltage level (v i =H), transistor T N is ON; and, a current I 1 flows through the transistors T 1 and T N . This is shown in FIG. 2. Current I 1 produces a voltage drop across transistor T 1 ; and, due to that voltage drop, the source to gate voltage of transistor T P is made less than the magnitude of the threshold voltage of transistor T P . Consequently, transistor T P turns OFF. As a result, no current flows through transistor T P , and so the output voltage v o on conductor 12 goes low (v o =L).
Conversely, when the input signal v i is at a low voltage level, transistor T N turns OFF; and, the current I 1 goes to zero. This is shown in FIG. 3. Due to the stopping of the current I 1 , the voltage drop across transistor T 1 decreases, and that in turn causes the gate to source voltage of transistor T P to rise and exceed the magnitude of the threshold voltage of transistor T P . Consequently, transistor T P turns ON. While transistor T P is ON, a current I 2 flows through transistors T 1 , T P , and T 2 . This current I 2 causes a voltage drop as it passes through transistor T 2 ; and thus, the output voltage v o goes high.
Now, in order to explain the operation of the translator circuit 10 in greater detail, reference should be made to FIG. 4. There, equations 1 thru 4 apply when transistor T N is ON and transistor T P is OFF. In equation 1, the term on the left hand side represents the voltage across transistor T N , and the term on the right hand side represents the magnitude of the threshold voltage of transistor T P . Equation 1 must be met in order to maintain transistor T P in an OFF state.
Next, the term on the left hand side of equation 1 may be rewritten as shown in equation 2. In equation 2, R 1 is the source-drain resistance of transistor T 1 , and R N is the source-drain resistance of transistor T N . Current I 1 equals the supply voltage V+ divided by R 1 +R N ; and that current I 1 times the resistance R N equals the voltage VT N .
Inspection of equation 2 shows that the equation can be met if the resistance R 1 is larger than resistance R N . This is stated by equation 3. Resistance R 1 is inversely proportional to the channel width W 1 of transistor T 1 , and resistance R N is inversely proportional to the channel width W N of transistor T N . Consequently, equation 3 can be met by making the channel width W N larger than the channel width W 1 . Preferably, as is stated by equation 4, the channel width W N is limited to being between 1.5 and 10 times larger than the channel width W 1 .
Next, consider equations 11 thru 15 of FIG. 4. Those equations apply when transistor T N is OFF and transistor T P is ON. In equation 11, the left hand term represents the voltage across transistor T P when it is ON, and the right hand term represents the breakdown voltage of transistor T P . Equation 11 must be met in order to insure that transistor T P does not break down.
For the reasons that are given in the background portion of this application, the breakdown voltage of transistor T P is just a couple of volts bigger than the supply voltage V+ or the supply voltage V- (which ever is larger). In that case, equation 11 can be written as equation 12 wherein the double vertical lines in the right hand term means "the larger of".
Also in equation 12, the term VT P is equal to the current I 2 as shown in FIG. 3 times the source-drain resistance of transistor T P . By utilizing this relationship, equation 12 can be rewritten as equation 13. There, the resistances R 1 , R 2 , R P respectively are the source-drain resistances of transistors T 1 , T 2 , and T P .
Inspection of equation 13 shows that it can be satisfied by making resistance R 2 greater than resistance R P . This is stated by equation 14. Resistance R 2 is inversely proportional to the width W 2 of the channel of transistor T 2 ; and, resistance R P is inversely proportional to the width W P of the channel of transistor T P . Preferably, equation 14 is satisfied by imposing the limitation of equation 15 wherein the channel width W P is limited to being between two and ten times the channel width W 2 .
Considering now equations 21 thru 24, they also apply when transistor T N is OFF and transistor T P is ON. Beginning with equation 21, it states that the high output voltage (v 0 =H) should be greater than 0.8 times the power supply voltage V-. This insures that the high output voltage is substantially larger than the low output voltage, and thus the output voltage swing can be used to switch other transistors (which follow the translator circuit in the BiCMOS logic block) ON and OFF.
At the same time, the high output voltage must not exceed the breakdown voltage v BD . Here, the breakdown voltage is just a couple of volts more than the supply voltage V+ or the supply voltage V- (whichever is greater), and thus equation 21 can be rewritten as equation 22. Inspection of equation 22 shows that it can be satisfied by making the resistance R 2 greater than the resistance R 1 . This is stated by equation 23. Preferably, equation 23 is met by imposing the constraint of equation 24 wherein the channel width W 1 of transistor T 1 is made three to ten times larger than the channel width W 2 of transistor T 2 .
Turning now to FIG. 5, the details of another preferred embodiment of a signal translator circuit 20 that is structured according to the invention will be described. This translator circuit 20 receives digital input signals v i on a lead 21 which are at BiCMOS voltage levels; and, it translates those signals into digital output signals v o on an output lead 22 which are at CMOS voltage levels. A high level for the input signals v i is ground; a low level for the input signals v i is the negative supply voltage V-; a high level for the output signals v o is the positive supply voltage V+; and a low level for the output signals v o is ground. In other words, this translator circuit 20 operates to undo the translation which the FIG. 1 translator circuit performs.
As FIG. 5 shows, the signal translator circuit 20 includes four field effect transistors which are labeled T P ', T N ', T 1 ', and T 2 '. Those transistors are interconnected between the V+ voltage bus 13, the ground bus 14, and the V- voltage bus 15 as shown. Transistor T N ' is a N-channel transistor, and the remaining transistors are P-channel transistors. Transistors T N ' and T P ' have their source labeled S and their drain labeled D; and, they operate in either an ON state or an OFF state as is described below to achieve the desired voltage translation. By comparison, transistors T 1 ' and T 2 ' have their gate connected to their drain, so they merely operate as resistors having respective source-drain resistances R 1 ' and R 2 '.
When the input signal v i is at a low voltage level (v i =L), transistor T P ' is ON; and, a current I 1 ' flows through the transistors T P ' and T 2 '. This is shown in FIG. 6. Current I 1 ' produces a voltage drop across transistor T 2 '; and, due to that voltage drop, the source to gate voltage of transistor T N ' is made less than the magnitude of the threshold voltage of transistor T N '. Consequently, transistor T N ' turns OFF. As a result, no current flows through transistor T N ', and so the output voltage v o on conductor 22 goes high (v o =H).
Conversely, when the input signal v i is at a high voltage level, transistor T P ' turns OFF; and, the current I 1 ' goes to zero. This is shown in FIG. 7. Due to the stopping of the current I 1 ', the voltage drop across transistor T 2 ' decreases, and that in turn causes the gate to source voltage of transistor T N ' to rise and exceed the magnitude of the threshold voltage of transistor T N '. Consequently, transistor T N ' turns ON. While transistor T N ' is ON, a current I 2 ' flows through transistors T 1 ', T N ', and T 2 '. This current I 2 ' causes a voltage drop as it passes through transistor T 1 '; and thus, the output voltage v o goes low.
In order to explain the operation of the translator circuit 20 in greater detail, reference should now be made to FIG. 8. There, equations 31 thru 34 apply when transistor T P ' is ON and transistor T N ' is OFF. In equation 31, the term on the left hand side represents the voltage across transistor T P ', and the term on the right hand side represents the magnitude of the threshold voltage of transistor T N '. Equation 31 must be met in order to maintain transistor T N ' in an OFF state.
Next, the term on the left hand side of equation 31 may be rewritten as shown in equation 32. In equation 32, R 2 ' is the source-drain resistance of transistor T 2 ', and R P ' is the source-drain resistance of transistor T P '. Current I 1 ' equals the magnitude of the supply voltage V- divided by R 2 '+R P '; and that current I 1 ' times the resistance R P ' equals the voltage VT P '.
Inspection of equation 32 shows that the equation can be met if the resistance R 2 ' is larger than resistance R P '. This is stated by equation 33. Resistance R 2 ' is inversely proportional to the channel width W 2 ' of transistor T 2 ', and resistance R P ' is inversely proportional to the channel width W P ' of transistor T P '. Consequently, equation 33 can be met by making the channel width W P ' larger than the channel width W 2 '. Preferably, as is stated by equation 34, the channel width W P ' is limited to being between 1.5 and 10 times larger than the channel width W 2 '.
Next, consider equations 41 thru 45 of FIG. 8. Those equations apply when transistor T P ' is OFF and transistor T N ' is ON. In equation 41, the left hand term represents the voltage across transistor T N ' when it is ON, and the right hand term represents the breakdown voltage of transistor T N '. Equation 41 must be met in order to insure that transistor T N ' does not break down.
For the reasons that are given in the background portion of this application, the breakdown voltage of transistor T N ' is just a couple of volts bigger than the supply voltage V+ or the supply voltage V- (which ever is larger). In that case, equation 41 can be written as equation 42 wherein the double vertical lines in the right hand term means "the larger of".
Also in equation 42, the term VT N ' is equal to the current I 2 ' as shown in FIG. 7 times the source-drain resistance of transistor T N '. By utilizing this relationship, equation 42 can be rewritten as equation 43. There, the resistances R 1 ', R 2 ', R N ' respectively are the source-drain resistances of transistors T 1 ', T 2 ', and T N '.
Inspection of equation 43 shows that it can be satisfied by making resistance R 1 ' greater than resistance R N '. This is stated by equation 34. Resistance R 1 ' is inversely proportional to the width W 1 ' of the channel of transistor T 1 '; and, resistance R N ' is inversely proportional to the width W N ' of the channel of transistor T N '. Preferably, equation 34 is satisfied by imposing the limitation of equation 35 wherein the channel width W N ' is limited to being between two and ten times the channel width W 1 '.
Considering now equations 51 thru 54, they also apply when transistor T P ' is OFF and transistor T N ' is ON. Beginning with equation 51, it states that the low output voltage (v o =L) should be less than 0.2 times the positive supply voltage V+. This insures that the low output voltage is substantially smaller than the high output voltage, and thus the output voltage swing can be used to switch other transistors (which follow the translator circuit in the CMOS logic block) ON and OFF.
At the same time, the low output voltage must not be so low that breakdown voltage v BD across transistor T 1 ' is exceeded. Here, the breakdown voltage is just a couple of volts more than the supply voltage V+ or the supply voltage V- (whichever is greater), and so breakdown can be prevented by requiring the low output voltage to exceed zero volts. Equation 51 can be rewritten as equation 52 by utilizing the relation that the low output voltage equals the positive supply voltage V+ minus the voltage drop across transistor T 1 '. Inspection of equation 52 shows that it can be satisfied by making the resistance R 1 ' greater than the resistance R 2 '. This is stated by equation 53. Preferably, equation 53 is met by imposing the constraint of equation 54 wherein the channel width W 2 ' of transistor T 2 ' is made three to ten times larger than the channel width W 1 ' of transistor T 1 '.
Two preferred embodiments of the invention have now been described in detail. In addition, however, various modifications can be made to those detailed embodiments without departing from the nature and spirit of the invention. For example, in the future, the transistors which make up the CMOS logic gates and modified CMOS logic may be scaled down in size. In that case the V+ and V- voltages may also be reduced from +5 and -5.2 volts. However, the circuit structure for the translator of FIGS. 1 and 5 can remain the same even when the V+ and V- voltages are lowered to about +3 and -3 volts. Also, as one other modification, the transistors T 1 , T 2 , T 1 ', and T 2 ' can be fabricated as resistors.
Accordingly, it is to be understood that the invention is not limited to the detail of the illustrated preferred embodiment, but is defined by the appended claims. | A signal translator circuit receives digital input signals of one voltage polarity and translates them to digital output signals of an opposite polarity. One embodiment of the translator converts conventional CMOS signal levels of +5 and 0 volts to modified CMOS signal levels of 0 and -5.2 volts. Another embodiment of the translator converts the 0 and -5.2 volt signals to the +5 and 0 volt signals. Both embodiments of the translator are made of transistors whose breakdown voltage only slightly exceeds +5 volts. | 7 |
BACKGROUND OF THE INVENTION
[0001] The invention relates generally to a device for treating fabric articles, including garments. More particularly, the present invention relates to a garment steamer.
[0002] There is a great need for portable, efficient devices to steam garments. It is well-known to use a steaming iron when ironing clothes and other garments. Non-iron devices called “steamers” have also been used to remove wrinkles and creases from clothes on a hanger or hanging from a rack by jetting steam to the clothes. These steamers do not have an ironing function because they lack the hot pressing plate found on irons. Both steam irons and steamers have been used for applying steam to remove creases and crinkles from hanging garments and other cloth materials. Steam has also been used in the cleaning of a variety of objects such as curtains, couches, furniture covers (e.g., couch covers), etc.
[0003] Many different types of irons and steam devices have been employed to iron and steam objects such as clothing. However, these steamers and steaming irons have their limitations, as described above and as follows. For example, U.S. Pat. No. 6,061,935 discloses an appliance for treating a garment with steamer and iron. However, this appliance is a relatively large, bulky, multi-part device that requires separate steamer and iron attachments that share a common water supply at a base to which the steamer and iron are attached. This system is not practical for situations that require portability.
[0004] While a device such as the one described above may provide means of steaming garments and the like, such a device can always be improved to provide better portability and flexibility.
[0005] Accordingly, there is a need for a garment steamer device that is portable and useful in a variety of applications. There is a further need for a garment steamer device that is modular. There is an additional need for a modular steamer device that is relatively compact in size and inexpensive. The present invention satisfies these needs and provides other related advantages.
[0006] Additional objects and advantages of the invention will be set forth in part in the drawings which follow, and in part will be obvious from the description, or may be learned by practice of the invention.
SUMMARY OF THE INVENTION
[0007] The present invention resides in a portable, modular garment steamer having a carriage and a steamer body separable from the carriage. The steamer body is detachably mounted to the carriage to allow for increased portability of the steamer. The steamer body includes a water tank, a reservoir and a steam chamber. A steam hose is connected to the steam chamber.
[0008] The water tank includes a cap with a self-closing flow valve. The reservoir includes a platform configured for mated engagement with the flow valve such that the flow valve is opened when the water tank is inserted into the reservoir. A tube connects the reservoir to the steam chamber. A drain plug connected to the tube permits easy draining of the steamer.
[0009] The steam chamber includes a water heating element for converting the water into steam. The water heating element and a first on/off switch are electrically and operationally connected by a power cord or similar structure. In addition, a thermostat may be electrically and operationally connected to the first on/off switch. A timer may also be associated with the first on/off switch. A second on/off switch that is electrically and operationally connected to the heating element may be included. When the second on/off switch is included, the first on/off switch may be electrically and operationally connected only to the power cord.
[0010] The power cord may be modular and detachable from the steamer body or it may be permanently attached and retractable into a cavity in the steamer body. The steamer body may include a detachable carrying strap. The carriage may include a garment rod and bumper caps over respective wheels.
[0011] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate several embodiments of the invention and together with the description, serve to explain the principles of the invention. It is to be understood that both the foregoing general description and the following drawings are exemplary and explanatory only and are not restrictive of the invention as to be claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] The accompanying drawings illustrate the invention. In such drawings:
[0013] FIG. 1 is an orthogonal view of a garment steamer embodying the present invention;
[0014] FIG. 2 is an orthogonal view of the garment steamer of FIG. 1 with the steamer removed from the truck;
[0015] FIG. 3 is a side elevational view of the garment steamer of FIG. 1 ;
[0016] FIG. 4 is a side elevational view of the garment steamer of FIG. 1 with the steamer removed from the truck;
[0017] FIG. 5 is a cross-sectional side elevational view of the garment steamer of FIG. 4 ;
[0018] FIG. 6 is a cross-sectional side elevational view of the garment steamer of FIG. 3 ;
[0019] FIG. 7 is a front elevational view of the steamer of FIG. 1 ;
[0020] FIG. 8 is a front elevational view of the carriage of FIG. 1 ;
[0021] FIG. 9 is a front elevational view of the garment steamer of FIG. 1 ;
[0022] FIG. 10 is a rear elevational view of the carriage of FIG. 1 ;
[0023] FIG. 11 is a rear elevational view of the steamer of FIG. 1 ;
[0024] FIG. 12 is a rear elevational view of the garment steamer of FIG. 1 ;
[0025] FIG. 13 is a partially exploded front elevational view of the carriage of FIG. 1 ;
[0026] FIG. 14 is a top plan view of the steamer of FIG. 1 ;
[0027] FIG. 15 is a bottom plan view of the steamer of FIG. 1 ;
[0028] FIG. 16 is a top plan view of the garment steamer of FIG. 1 ;
[0029] FIG. 17 is a top plan view of the carriage of FIG. 1 ; and
[0030] FIG. 18 is a bottom plan view of the carriage of FIG. 1 .
DETAILED DESCRIPTION OF THE INVENTION
[0031] The present invention is useful in a variety of applications that require flexibility, portability and modularity. This device is usable in any situation where an object needs to be steamed. These situations can occur anywhere there is a need to steam an object, such as in the home, in a hotel, at the office, or the like. The present invention is relatively compact in size and inexpensive.
[0032] As shown in the drawings for purposes of illustration, the present invention resides in a garment steamer. With reference to FIGS. 1-18 , a garment steamer device 20 includes a steamer 22 and a four-wheel truck carriage 24 upon which the steamer 22 rests. The garment steamer 22 can be placed upon the carriage 24 for portability or removed from the carriage 24 and shoulder-carried for convenience. In a first configuration, the steamer 22 is operably and detachably mounted only to the carriage 24 ( FIGS. 1, 3 , 6 , 9 , 12 and 16 ), and in a second configuration the steamer 22 is detached from the carriage 24 ( FIGS. 2, 4 , and 5 ).
[0033] The steamer 22 includes a housing 26 for electrical and mechanical parts. The steamer 22 includes a modular water tank 28 for holding a certain amount of water; the tank 28 holding the water that is to be converted into steam. The water tank 28 includes a grip indent 30 on both sides of the tank 28 for assisting a user in grasping the tank 26 for engagement with or removal from the housing 26 of the steamer 22 . The water tank 28 is made from a semi-transparent or clear plastic so that the level of water within the tank 28 may be seen by a user. The housing 26 and tank 28 are shaped so as to present a continuous appearance when mated.
[0034] The tank 28 includes a cap 31 with a flow valve 32 designed so as to open when the tank 28 is mated to the housing 26 and close when the tank 28 is removed from the housing 26 . When the tank 28 is aligned for mating to the housing 26 , the valve 32 is facing downwards in a closed position. When the tank 28 is mated to the housing 28 , one portion 34 of the valve 32 abuts against a platform 36 within the housing 26 that opens the valve 32 as the valve 32 comes into contact with the platform 36 . When closed, another portion 38 of the valve 32 seals an aperture 40 of the tank 28 .
[0035] The platform 36 is located in a reservoir 42 within the steamer 22 . Water within the reservoir 42 drains downward along a tube 44 that leads to a lateral tube 46 . The lateral tube 46 connects to a steam chamber 48 within the housing 26 . The tube 44 also leads to a drain plug 50 located at the bottom of the steamer 22 . The drain plug 50 is hinged so as to allow a user to open the drain plug 50 in order to drain the reservoir 42 and water from the water tank 28 when the tank 28 is mated to the housing 26 .
[0036] A gasket 52 seals the top open aperture 54 of the reservoir 42 when the tank 28 is mated to the steamer 22 , forming a press-fit seal.
[0037] The steam chamber 48 is surrounded by a heat shield 55 within the housing 26 . The steam chamber 48 holds a certain amount of water and includes a heater 56 which heats the water in the chamber 48 in order to produce steam from the water. The heater 56 may be in the form of at least one metallic element which heats the water in the chamber 48 when electric current is applied to the metallic element. The metallic element may be made from any highly conductive metal, such as copper. The steam produced by the heater 56 is passed into a steam passage 58 within the steamer 22 and out of the steamer 22 through a steam hose 60 . The steam hose 60 is connected to the steamer 22 by a hose lock-nut 62 and a lock nut cover 64 . Various kinds of attachments for steaming garments may be connected at the free end of the hose 60 .
[0038] The steamer 22 includes an expandable power cord 66 with a conventional plug (not shown) that plugs into a conventional wall electrical socket. Power from the power cord 66 supplies the power to the electrical system of the steamer 22 and the power cord 66 is electrically and operationally connected to an on/off switch 68 on the steamer 22 that regulates the flow of electrical power through the device 20 . The on/off switch 68 is electrically and operationally connected through a plurality of electrical cables 70 to the heater 56 . The on/off switch 68 is also electrically and operationally connected to a thermostat 72 . The thermostat 72 automatically cuts power through the electrical system if the temperature within the steam chamber 48 gets too high. The on/off switch 68 also activates/deactivates emission of steam from the steamer 22 . In the alternative, the power and steaming functions could be controlled by separate switches. One end of the power cord 66 is permanently attached to the steamer 22 . In the alternative, the power cord 66 may be modular so as to be attachable/detachable to the steamer 22 . In another alternative, the power cord 66 may be retractable and stored within a cavity (not shown) in the housing 26 when the steamer 22 is not in use. In the alternative, a timer may be associated with the on/off switch 68 to provide an automatic power shut-off.
[0039] The steamer 22 includes a carrying strap 74 with strap lock 76 for adjusting the length of the strap 74 . The carrying strap 74 is attachable to and removable from the steamer 22 . The steamer 22 further includes a plurality of rubber feet 78 on the bottom of the steamer 22 which allow the steamer 22 to rest upon a surface without the housing 26 touching the surface.
[0040] The steamer 22 also includes a truck carriage release mechanism 80 to disengage the steamer 22 from the carriage 24 when the steamer 22 and carriage 24 are mated. The release mechanism 80 includes a release button 82 located near the bottom rear of the steamer 22 .
[0041] The carriage 24 includes an expandable garment rod 84 that is telescopically expandable between a recessed position and an expanded position. The garment rod 84 is set in a desired amount of extension by the user and then secured into position using a garment rod fastening device 86 located at the base of the garment rod 84 . The fastening device 86 is turned in one direction to hold the rod 84 in a desired amount of expansion and turned in the opposite direction to loosen the hold on the rod 84 so that the rod 84 may be adjusted to a lesser or greater length.
[0042] The carriage 24 includes four wheels 88 or casters located at the corners of the carriage 24 . A bumper cap 90 is located above and around each of the wheels 88 in order to protect furniture that the carriage 24 may pass near. The bumper cap 90 is designed with at least two press-fit mechanisms 92 designed to pass through matching apertures 94 in the carriage 24 so that the press-fit mechanisms 92 snap-in place and hold the bumper cap 90 in position. A shank 96 of each wheel 88 passes through an aperture 98 at a particular corner of the carriage 24 . The shank 96 is designed so as to press-fit into a mating aperture 100 on the bumper cap 90 .
[0043] The carriage 24 includes a channel 102 for the power cord 66 to pass along in order to prevent the cord 66 from getting tangled. The carriage 24 further includes an aperture 104 located under and aligned with the drain plug 50 of the steamer 22 .
[0044] The carriage 24 includes a recess 106 located on a top surface of the carriage 24 that forms an outline of the steamer 22 , shaped and sized so as to receive the steamer 22 when mated to the carriage 24 . The carriage 24 further includes first and second posts 108 , 118 for engaging the release mechanism 80 of the steamer 22 when is mated to the carriage 24 .
[0045] The carriage 24 may be made of molded plastic or aluminum.
[0046] The steamer 22 engages the carriage 24 with a slide-in lock as the steamer 22 and carriage 24 may be operably and detachably mounted to each other. The steamer 22 and carriage 24 are slidingly engaged from a first direction at the posts 108 , 110 . A post 112 extending from a recess 114 within the bottom of the steamer 22 passes through a bore 115 in post 108 . Concurrently, as the steamer 22 is lowered towards the recess 106 of the carriage 24 , the post 110 passes into another recess 118 of the steamer 22 where the post 110 engages the release mechanism 80 of the steamer 22 . The post 110 engages a post 120 extending into the recess 118 . The post 120 is connected on one end to a spring 122 located within the steamer 22 . As the post 120 of the steamer 22 engages the post 110 of the truck, pressure is exerted against the spring 122 which itself exerts pressure against the post 120 which, in turn, presses against the post 110 until the post 120 passes into a bore 124 within the post 110 . The spring 122 ‘holds’ the post 120 in position until a user presses the release button 82 . A spring 126 aligned with the post 120 is connected to the release button 82 . When the release button 82 is pressed, the spring 126 contacts the post 120 and exerts sufficient pressure against the post 120 so as to push the post 120 sufficiently through the bore 124 of post 110 so as to allow the post 120 to be disengaged from the post 110 of the carriage 24 . When both posts 112 , 120 of the steamer 22 engage the posts 108 , 110 of the carriage 24 , the steamer 22 is mated to the carriage 24 .
[0047] In use, a user may prepare a garment for wear by eliminating wrinkles and other creases from the garment by steaming the garment. The user, holding the tank 28 upside down, fills the tank 28 of the steamer 22 with water by pouring water through the aperture 40 of the tank 28 . When the tank 28 is upside down, the flow valve 32 is open so that water can enter the tank 28 . Once the tank 28 is filled to a desired level, the user then turns the tank 28 over which closes the valve 32 . The user attaches the tank 28 to the steamer 22 by inserting the tank 28 , cap 31 facing downward, into a recess 128 of the steamer 22 above the reservoir 42 . The tank 28 press-fit seals against the gasket 52 that surrounds the top open aperture 54 of the reservoir 42 when the tank 28 is mated to the steamer 22 . The platform 36 presses against the valve 32 , opening the valve 32 and allowing water to flow into the reservoir 42 and into the steam chamber 48 . The user may then connect the power cord 66 of the steamer 22 to an electrical source and activate the on/off switch 68 so that the water may be converted into steam.
[0048] The user then may adjust the height of the garment rod 84 , place a garment upon the garment rod 84 , and then proceed to steam the garment. In the alternative, the garment rod 84 may include an arm connected to the rod 84 and pivoted from alignment parallel to the rod 84 to approximately perpendicular to the rod 84 so that a user may drape a garment over the arm for steaming.
[0049] The above-described embodiments of the present invention are illustrative only and not limiting. It will thus be apparent to those skilled in the art that various changes and modifications may be made without departing from this invention in its broader aspects. | A portable, modular garment steamer includes a carriage and steamer body detachably mounted thereon. The steam body includes a water tank, a reservoir and a steam chamber having a water heating element. A steam hose connected to the steam chamber permits a user to control the direction of steam exiting the steamer. The carriage includes wheels making the assembly movable. In addition the steamer body includes a carrying strap providing for portability when separated from the carriage. On/off switches as well as a thermostat and/or a timer permit the control and selective operation of a water heating element to control the generation of steam. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates generally to microwave ovens and specifically to combination microwave and thermal ovens.
2. Prior Art
In microwave oven design and construction the ability to prevent microwave energy leakage is a major concern. Leakage must be prevented in microwave ovens in order to protect users from exposure to that energy. Federal standards require that the radiation leakage be less than 1 milliwatt per square centimeter at 5 centimeters distance from the microwave oven door, for the fundamental ISM band and less than 25 microvolts per meter at a at a distance of 1,000 feet for all out of band radiation.
Microwave energy will not transmit through solid metal. Therefore, the oven cavity and door in microwave ovens are formed from metal. Since the door and oven are not formed as a unified member, leakage may occur through the joint between the door and the wall of the oven cavity. In ovens where the only cooking energy is microwave, a seal can be effectively formed which will conductively seal the door and wall of the oven cavity and thereby prevent leakage of the microwave energy. In some prior art microwave ovens a flexible gasket is used to prevent that leakage. In other prior art microwave ovens a choke which causes an electrical short is employed. However, when an oven is constructed which employs both microwave energy and thermal energy for cooking, no sealing device has been designed or constructed which will effectively prevent microwave leakage. The problem results because high temperatures cause stress and expansion of the cavity walls and gasket which reduces the contact area between the gasket and cavity wall and thereby permits leakage of microwave energy. This thermal expansion problem is significantly increased when the self-cleaning feature is added to ovens employing both thermal and microwave energy. In these ovens, the temperature during the self-cleaning cycle will vary between 865° and 1,000° Fahrenheit. At these high temperatures the metal walls and faces of the oven are subjected to expansion and stresses not normally found in ovens only utilizing microwave energy. These stresses and expansions cause the alignment of the sealing mechanisms to change. There is no known oven which employs both thermal and and microwave energy in a self-cleaning oven which operates in the 2.450 GHz ISM band, and accordingly, there is no known device for sealing the door of such an oven.
It is acknowledged that in the prior art some microwave ovens employ chokes as electrical shorts; some employ flexible conductive gaskets, and others employ a microwave absorbing cartridge. However, none of those prior art devices employ any combination of the various techniques for sealing the door of the oven. Moreover, the present invention provides a one-half wave-length choke. This specific wave length choke is constructed such that minimum energy levels exist near the door gasket. This design prevents build-up of energy near the door gasket which could cause destruction of the gasket and thereby reduce the effectiveness of the combined choke and gasket which eliminates most of the total ISM band leakage.
The present invention overcomes the problems that exist in the prior art and provides an efficient sealing device for a combination thermal-microwave oven.
SUMMARY OF THE INVENTION
A device for preventing leakage of microwave energy from the door of a combination thermal and microwave oven is disclosed. The invented device is comprised of: a one-half wavelength choke, a flexible conductive gasket and a microwave absorbing block. The one-half wave length choke acts as an electrical short and when matched with a conductive gasket suppresses the majority of the ISM band microwave energy directed at the joint between the door and the oven cavity. The microwave absorbing block suppresses the remainder of the microwave leakage. In combination these devices are effective in sealing a thermal microwave oven even when extremely high temperatures are used for self-cleaning.
It is an object of the present invention to provide a device which will suppress the radiant leakage of microwave energy from the joint between the door and oven cavity walls of a combination microwave and thermal oven.
It is another object of the present invention to provide a device for suppressing the radiant leakage of microwave energy in a combination thermal microwave oven which uses extremely high temperatures for self-cleaning.
It is another object of the present invention to provide a sealing device which will reduce the radiation of microwave energy to less than 1 milliwatt per square centimeter at 5 centimeters distance from the oven door for the fundamental ISM band and less than 25 microvolts per meter at 1,000 feet distance for all out of band radiation.
It is still another object of the present invention to provide a one-half wave length choke which will force minimum energy to exist at the flexible gasket and thereby prohibit destruction of that gasket because of high energy levels which might otherwise exist.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross-sectional view of the oven and oven door, illustrating the relative locations and structure of the present invention;
FIG. 2 is a partial blown-up cross sectional view taken within the circumscribed area labeled 2--2 of FIG. 1;
FIG. 3 is an alternate embodiment of the invention illustrating an alternate placement of the flexible conductive gasket; and
FIG. 4 is a second alternate embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring first to FIG. 1, the environment and relative location of the present invention in respect to the oven cavity is shown. The oven cavity 10 is defined by outer walls 11 and 12, inner walls 13 and 14 and a back and two side walls, not shown. The door 20 is shown in its closed position. The microwave leakage suppressing device of the present invention is comprised of a choke 30, a flexible conductive gasket 40 and a Ferrite impregnated rubber cartridge 50. The relative positions and placement are illustrated in FIG. 1.
In the design and construction of microwave ovens, Federal law restricts the amount of leakage of microwave energy that can be emitted from the oven. Those requirements limit the radiation to less than one milliwatt per square centimeter at 5 centimeter's distance from the door for the fundamental ISM band and less than 25 microvolts per meter at 1,000 feet distance for all out of band radiation. Radiation of microwave energy can be eliminated if the oven cavity is totally enclosed by metal. However, the oven cavity must have a door in order to be operational, and, hence, the joint between the walls of the oven cavity and door become a source of leakage of microwave energy.
Referring now to FIG. 1, the door will be described, it being understood that the door could be constructed in many alternate manners to achieve the same results. Thus, a typical oven door is described herein.
The oven door 20 is formed from metal and has an outer surface 17 and an inner surface designated generally as 18. The inner surface 18 is porcelain or another suitable dielectric material. The outer surface is for decoration only. Insulation 19 and 21 is disposed there between to prevent loss of thermal energy. A latch 25 is provided for locking the door. The latch may be electronically controlled to prevent opening of the door while the self-cleaning cycle is in operation. The door pivots on hinges (not shown) around its lower portion designated generally as 23. The door has a highly conductive strip 61 formed thereon. It traverses the entire perimeter of door 20 as shown in FIG. 1, and is coupled directly to the metal of the door making electrical contact therewith. Fabrication of the strip is described hereinafter.
The oven cavity 10 may also be formed similar to oven cavities well-known in the prior art, with one modification being necessary. That modification is the high conductive strip 60 which is disposed around the perimeter of the oven cavity. Strip 60 is normally formed after the porcelain finish has been applied. However, strip 60 must be conductively connected to wall 15. Thus, during porcelain application that area is masked. In the preferred form, the strip is aluminum loaded porcelain, but it could be formed from any substance which is conductive and not subject to break-down at temperatures in the operating range of the oven. Strip 61 is form similar to strip 60.
The leakage path formed by the joint can best be described in reference to FIG. 2. Any leaking microwave energy must pass from the oven cavity and along the areas labeled 34, 45 and 46. If the escaping microwave energy reaches point 48 it will be radiated from the oven door. The present invention is comprised of 3 components which operate in combination to eliminate leakage. Removal of any individual component would incapacitate the system. The 3 three components for suppressing the leakage of microwave energy are disposed along the joint. The device must be constructed to operate under adverse conditions and have a very low failure rate. The gasket must be capable of effecting a conductive seal between the door and oven wall even if food stuff or other debris is introduced along its contact area. The gasket must also be capable of maintaining that seal at all times and especially during high temperature cycles which create expansion and stress.
The present invention employs in combination a choke 30, a sealing gasket 40 and an absorbing cartridge 50, each of which will be described in detail herein below. The choke 30 of the present invention is defined by interior oven wall 14, door walls 31, 33 and 32 and gasket 40, as illustrated in FIG. 2. The door wall 32 is spaced apart from door wall 31 and is an extension forming an enclosed area 35 having one open end 38. Enclosed area 35 is terminated at 37 by wall 16 forming a solid barrier with wall 18. Thus, a generally U-shaped area is formed in which microwave energy may travel. The length of each side of the U-shaped choke 30 is designated as D 1 . In the presently preferred embodiment distance D 1 is equal to the length of one-quarter of the wave length of the generated microwave energy. Thus, the total length of the choke is one-half wave length between point 36 and point 37. Since the walls 32, 14, 31 and 33 are metal, microwave energy emitted from the oven will traverse along paths 34 and 35 to point 37 and be reflected back on the same path. As that energy is reflected back to point 36 it acts as an electrical short thereby reducing the energy entering path 34.
In the presently preferred form, the length and construction of the choke 30 forces minimum energy to occur at point 38 and maximum energy to occur at points 36 and 37. It is important that minimum energy occur at point 38 since it is in that area the flexible conductive gasket 40 is disposed. If maximum energy occurred at point 38, the probability that gasket 40 would be destroyed after a very short usage is highly probable. If gasket 40 is destroyed, choke 30 cannot function since microwave energy will traverse between the choke and oven wall 15 and along the area designated as 45 and pass out of the oven rather than being forced along path 35 and reflected back to point 36 to act as the electrical short.
In the presently preferred form, the gasket 40 is formed having an aluminum strip 41 as the core. A stainless steel spring 42 is disposed adjacent to core 41. A mat 43 of fiberglass is then disposed adjacent to the spring and core and a Inconel knitted outer jacket 44 is disposed about the mat 43. The gasket is formed having a main body which contains the core and spring and a tip 49 which extends perpendicular therefrom. The main portion of the gasket is positioned such that the longitudinal axis of the core 41 is disposed parallel to the oven door and interior wall 15 of the oven cavity. The tip 49 is disposed between wall 47 and 33 of the door and secured therein by tip 49 being disposed around tip 52 of wall 33.
The gasket 40 is disposed around the entire perimeter of the oven door as heretofore described. This forms a complete seal around the door. When the door is positioned into the closed position as shown in FIG. 1, the metal gasket is compressed against the conductive strip 60 which is disposed on interior wall 15 and the conductive strip 61 on surface 33 and 47 of door 20. Spring 42 is slightly compressed such that it urges the outer jacket into contact with conductive strips 60 and 61. In the presently preferred form, metal to metal contact, between the door 20 and cavity wall 15 must exist or leakage of microwave energy will occur. When an effective seal is created between the wall 15 and door 20 by gasket 40 microwave energy will not leak therefrom and the gasket will effectively seal the cavity and create the electrical short in conjunction with choke 30. However, if gasket 40 does not function, choke 30 will not operate and no seal will exist.
In ovens which only use microwave energy to cook, the gasket previously described would be effective unless food stuff or other debris caused the gasket not to seal. If the gasket doesn't seal for some reason, leakage will occur unless additional protection is provided. The problem becomes more acute in ovens which use both thermal and microwave energy for cooking, and even more acute in self-cleaning ovens which have temperatures ranging between 865° and 1,000° Fahrenheit. At these high temperatures the metal walls in the oven, such as 15, 14, and 16 are subjected to expansion and stress not normally found in non-thermal ovens. The stresses and expansions cause the alignment and sealing of the gasket and wall to change; and, hence, the possibility of leakage of microwave energy.
In order to stop leakage that may occur from the gasket and choke, the present invention employs a microwave absorbing cartridge 50 which is disposed in the outer wall 12 of the oven, such that any leaking microwave energy must pass thereby. Cartridge 50 is formed from a ferrite impregnated rubber in the presently preferred embodiment. In alternate embodiments, different microwave absorbing material may be employed. The efficiency of the material used will determine the cartridges efficiency and different materials can be used effectively depending on their dielectric and energy absorbing capabilities. Cartridge 50 is disposed in aperture 51 of wall 12 such that one face of the cartridge forms a portion of the wall and defines a portion of the area labeled 46.
The presently preferred embodiment of the invention has been described as having a one-half wave length choke, however, in an alternate embodiment a choke having a different magnitude could equally well be employed. The only restriction being that in any alternately formed choke the minimum energy level exists at the region near gasket 40. Alternately microwave absorbing cartridge 50 can be disposed at various positions along the areas designated 45 and 46 and equally well be as effective. In other forms, gaskets of different materials may equally well serve to provide the conductive contact and barrier for the microwave energy. The invented device is comprised of the choke, gasket and absorber in combination such that each element functions independently and in cooperation with each other element.
The first alternate embodiment is illustrated in FIG. 3. There the metal gasket is displaced from its position as illustrated in FIG. 2 such that distance D 3 exists between the end 70 of the metal gasket and point 71 located at the juncture of walls 15 and 14. The distance D 2 between point 70 and 72 is constructed such that the total distance D 2 plus D 3 is equal to one-half the length of a wave length.
In the second alternate embodiment illustrated in FIG. 4 a metal squeeze gasket 73 is forced to contact sides 14b and 15b to form a electrical contact therebetween. The construction of the inner walls of the oven cavity in this manner permits a much smaller sheet of metal to be employed in the construction of the oven cavity and may be economically more feasible than the presently preferred embodiment. Here D 4 is equal to the distance D 1 or one-quarter of the length of the wave length.
However, while the preferred embodiment of the present invention has been described in detail herein, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention. | The present invention is a device for sealing the door of a self-cleaning combination thermal and microwave oven from microwave energy leakage. The invented device provides in combination a wavelength choke, a conductive gasket and a microwave absorber. The choke and gasket suppress the ISM band radiation and most of the out of band radiation while the microwave absorber suppresses the balance of the out of band radiation which may result by improper door closure. The combination is particularly useful in combination microwave and thermal self-cleaning ovens where high temperatures cause expansion and stress not normally encountered in microwave ovens. | 7 |
FIELD OF THE INVENTION
The present invention relates to mass spectrometer systems useful for obtaining matrix-assisted laser desorption measurements. More particularly, this invention is directed to an automated mass spectrometer system for combining high sample throughput with high reliability.
BACKGROUND OF THE INVENTION
Matrix-assisted laser desorption and ionization (MALDI) is a relatively new technique that allows very large molecules, such as DNA fragments and proteins, to be desorbed from a solid sample and ionized without significant decomposition. Coupled with mass spectrometry, this technique allows the molecular weights of biological polymers and other large molecules, including industrial polymers, to be precisely determined. One version of MALDI is described in a 1991 article in Rapid Communications in Mass Spectrometry, Vol 5, Pages 198-202. A mass spectrometer suitable for obtaining highly reliable matrix-assisted laser desorption measurements is described in U.S. Pat. 5,045,694.
Most MALDI applications to date have employed time-of-flight mass spectrometers, although magnetic deflection, Fourier Transform ion cyclotron resonance, and quadrupole ion trap mass analyzers have also been used. A liquid solution of the sample to be analyzed is mixed with a solution containing an appropriate matrix, and a small aliquot of this mixtures is deposited on the source of the mass spectrometer (inside a vacuum system). A vacuum lock is generally utilized to avoid venting the vacuum system. Loading a sample typically requires from one to several minutes, and the attention of a skilled operator. A diligent operator should theoretically be able to load and run a sample every five or ten minutes using such a system, but it is difficult to maintain such a rate over an extended period. U.S. Pat. 5,288,644 discloses one technique for reducing the required time. A plurality of samples are loaded onto the solid surface of a disk, which is rotated by a stepper motor for positioning each sample respectively for striking by a laser beam.
Further improvements in the loading of samples for the laser desorption mass analysis are required for this analytical procedure to gain greater acceptance and significantly increase the use of this analytical tool. The disadvantages of the prior art overcome by the present invention, and an improved system is hereinafter disclosed for obtaining matrix-assisted mass spectrometer measurements. The loading of the samples is highly automated for achieving both high sample throughput and high reliability. The present invention has a wide range of application, and may be used with various analytical methods.
SUMMARY OF THE INVENTION
The present invention provides a highly automated system for preparing, loading, and running samples by MALDI mass spectrometry. Each step in the process may be controlled and monitored by a computer. All sample processing and identification information is recorded along with the mass spectra measurements, so that automated processing of the data may be performed. The typical input to this system is a collection of samples in relatively crude or unprocessed form, and the output provides direct answers to specific questions posed by the scientists relative to the samples. This system is particularly useful in applications that require processing a large number of samples to provide the required data. Examples include DNA sequencing on the scale required by the Human Genome Project, protein sequencing, and determination of the locations and nature of post-translational modifications of proteins. While there are many potential applications of this invention, the Human Genome Project provides a particularly timely example of the need for this advancement. The DNA that composes the human genome has about 3.5 billion base pairs. Although highly developed techniques for sequencing DNA has been developed, at least a decade would be required using available techniques to accurately sequence even one such DNA. Completion of the genome project will require sequencing thousands or possibly millions of such genomes from both humans and other oganisms. The present invention will accordingly be described in detail below with particular emphasis on its application to DNA sequencing, but it should be recognized that it has other applications.
It is an object of this invention to provide improved equipment and techniques for performing MALDI mass spectrometry analysis. The equipment and techniques of this invention substantially reduce both the time and expertise required to load, run, and analyze multiple samples, thereby significantly reducing the cost of the analysis.
A significant feature of this invention relates to the effective combination of mass spectrometry equipment and techniques with matrix-assisted laser desorption ionization equipment and techniques. The equipment and techniques may be utilized to substantially reduce the cost of DNA sequencing. The invention may also be used for determining the molecular weight of various large molecules, such as biological and industrial polymers.
A significant advantage of this invention relates to the reduced time required for mass spectrometry analysis of multiple samples. The invention is particularly well suited for use with a time-of-flight mass spectrometer.
These and further objects, features, and advantages of the present invention will become apparent from the following detailed description, wherein reference is made to the figures in the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 depicts one embodiment of a sample holder according to the present invention for loading multiple samples for mass analysis.
FIG. 2 depicts an alternate embodiment of suitable apparatus for loading multiple samples for mass analysis.
FIG. 3 is a block diagram of an automated system for processing and preparing samples, and for transferring multiple sample aliquots on a sample plate to selected sample positions.
FIG. 4 is a top view of a suitable system for automatically transferring sample plates between a sample storage chamber and an ion source chamber of a mass spectrometer.
FIG. 5 is a front view of the system shown in FIG. 4 .
FIG. 6 is a top view of a simplified vacuum lock assembly prior to loading a sample plate into the vacuum lock chamber.
FIG. 7 is a top view of the simplified vacuum lock assembly as shown in FIG. 6 after loading the sample plate into the analysis chamber.
FIG. 8 is a schematic diagram of a fully automated system according to the present invention.
FIG. 9 is a schematic illustration of a matrix-assisted laser desorption ion source combined with a simplified representation of a mass spectrometer according to the present invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
The system according to this invention typically involves many components integrated under computer control into a fully automated system. A typical system of ten primary components includes: (1) a sample plate or other sample receiving surface upon which a large number of physically separated and distinguishable samples can be loaded in liquid solution then allowed to dry; (2) identification means for uniquely identifying each sample position and sample plate; (3) an automated system for processing and preparing samples and transferring aliquots to selected sample positions on a sample plate; (4) drying means for storing one or more sample plates in a controlled environment; (5) transferring means for automatically or manually transferring a plurality of sample plates from the controlled environment into the sample receiving chamber of the MALDI mass spectrometer; (6) an automated vacuum lock system for transferring sample plates between the receiving chamber and the ionization source of the MALDI mass spectrometer without significantly increasing the pressure in the mass spectrometer vacuum system; (7) sequencing means for sequentially placing each sample on the sample receiving surface in the path of the laser beam, so that its MALDI spectrum is recorded and stored along with the sample identification information; (8) means for automatically adjusting the laser intensity and sample position relative to the laser beam to obtain MALDI spectra which meet or exceed predetermined criteria; (9) means for automatically calibrating the mass axis of the MALDI mass spectrometer; and (10) means for automatically interpreting the MALDI mass spectra obtained from one or more samples to determine and produce the answer to a specific question. A scientist may thus make inquiry as to the sequence of the bases in a particular DNA fragment, and the system of this invention will rapidly provide the answer in a highly cost-effective manner.
In some applications manual operations may be substituted for the corresponding automated step, but the full power and speed of the invention is realized when operator intervention is required at most, once or twice per day. Each of the ten primary components (and/or corresponding steps) which may comprise an exemplary system is described in more detail below.
1. Sample Receiving Surface
A preferred embodiment of a sample receiving surface is illustrated in FIG. 1 . The depicted sample plate 10 consists of a thin, substantially square plate 12 of stainless steel or other suitable electrically conducting material approximately 1.5 mm thick and 50 mm wide. The plate 10 may contain precisely located holes to allow the position and orientation of the plate to be accurately determined relative to a moveable stage, which is required both in the sample loading step and in the ion source of the mass spectrometer. The sample plate 10 also contains a plurality of precisely determinable sample positions 16 on the upper sample receiving surface 18 of the plate. These sample positions may be determined by a number of photoetched and numbered sample positions or wells as illustrated in FIG. 1 . Alternatively, a number of sample positions may be identified by electroplated sample spots and numbers on the surface 18 of the sample plate, with the sample identification providing the row and column number of a respective adjoining sample, i.e., position identification 34 being the sample in the third row and the fourth column of the plurality of samples on the plate 10 .
A plate 10 may thus contain 100 sample positions each identified by a sample spot which is about 2.5 mm in diameter in a precisely known location on the plate, with each sample support being suitable for accepting a few microliters of sample solution. Each sample spot may be further identified by a corresponding number similarly plated or etched on the surface 18 . Alternatively, the plate may contain a larger number of spots in which photoetched sample wells or photoplated sample spots of appropriate diameter in precisely known locations are prepared on the sample surface without the corresponding sample numbers on the surface. The known sample coordinates thus may be sufficient to identify each sample well or spot. In the case of a 400 sample array (20 rows and 20 columns), 2 mm sample wells or spots have been used successfully. For a 1024 array (32 rows and 32 columns), a 50 mm square plate and 1 mm diameter sample positions have been successfully used. Another alterative is to use a smooth unmodified sample plate in which the x-y coordinates are sufficient to define a unique sample position. The detailed description of the invention discussed below utilizes 50 mm plates with square arrays of sample positions which can accommodate up to 1024 distinguishable sample positions. Any distribution of samples over a surface, either known or unknown, can be accommodated. Sample plates of a variety of geometries could be used, including circular, rectangular, and regular and irregular polygons. The maximum size of the sample plate is limited only by the size of the ion source vacuum chamber and travel limits of the x-y table on which the sample receiving stage is mounted. It should be understood that smaller or larger numbers or distinguishable sample positions may thus be defined on sample receiving surfaces of other geometries.
In a preferred embodiment as illustrated in FIG. 1, a ferromagnetic material handle 20 is attached along one edge of the plate on the bottom side, i.e., the side opposite the receiving surface for the samples. This handle 20 may have a rectilinear cross-sectional configuration, and is used to engage an electromagnetic device for the purpose of transporting the sample plate between component systems.
The sample plate 10 has beveled comers corners 22 yet provides a total square surface having 50 mm sides interior of the beveled comers corners on the top surface of the plate 10 for receiving multiple samples. Samples may be deposited on this plate in a variety of ways, and for explanation purposes it may be assumed that an array of circular spots 16 is photoetched into the plate 10 along with identifying numbers. This arrangement easily accommodates up to 1024 sample spots each 1 mm in diameter in a 32×32 array without identifying numbers. Each of these 1024 sample spots will accommodate about 100 nanoliters of sample solution.
As shown in FIG. 2, the samples alternatively may be deposited on the ends 24 of removable pins 26 , and the pins locked into a two dimensional array using a sample holder positioned on a sample plate 10 A. A suitable holder 28 may have a rectangular horizontal cross-section, and may be sized to receive a 5×5 array of vertical pins. Samples of interest are thus deposited in known locations or spots on the surface of the sample holder. In other cases, the locations of samples of interest may not be of particular significance. For example, a system may be employed with samples deposited by blotting from a two-dimensional gel, in which case samples of interest may be distributed in an unknown pattern over the sample surface.
As shown in FIG. 1, the sample plate 10 has two or more precisely located holes 14 A, 14 B and 14 C each located near an edge of the plate 10 . These holes 14 locate the sample holder when installed in the sample receiving stage in the ion source of the mass spectrometer and in the sample transport trays. The magnetic material bar 20 may be engaged by an energized electromagnet (not shown) to assist in transporting the sample holder into the sample receiving stage, as discussed subsequently.
2. Identification of Sample Position and Plate
The x-y coordinate of each sample position on one side (typically the top side) of the sample plate may be used to determine a unique sample position on each sample plate. The diameter of a sample spot centered on each position may be used to further define a sample position. The minimum data required to uniquely identify a sample position is the x-y coordinate and the diameter of the spot. As discussed above, the sample position may be further defined by a photoetched well or photoplated spot centered at the corresponding x-y coordinate on the sample plate, and may be even further defined by the corresponding number etched or plated near the corresponding sample spot.
Each particular sample plate may be identified by a serial number etched into the top surface of the plate or attached to or etched into the bottom surface of the plate. A computer readable bar code may be used with a sufficient number of digits to uniquely identify the sample plate relative to any other which might be encountered within a series of similar runs. The system involved in applying the samples to the sample plates and those for loading the plates into the mass spectrometer as discussed below may also be equipped with bar code readers to provide the required identification of the sample plates.
3. Processing and Preparing Samples
The details of this component will depend on the application, the types of samples to be tested, and the degree to which the samples are prepared and purified prior to being input to the analysis system described below. The following discussion sets forth the representative steps required to carry out an automated MALDI analysis. It should be appreciated that additional automated sample preparation and purification steps could be added. Rate-determining steps may be used, for example, to determine the speed with which the complete determination can be done.
The invention is particularly suited for DNA sequencing. For this purpose, it is assumed that a set of sequencing mixtures has been prepared off-line using either the Maxxam-Gilbert or Sanger method. The mixtures may be presented to the system in the form of liquid solutions in small vials or tubes in a try which may be accessed by an autosampler. Substantially the same samples in the same form may be presented for separation by electrophoresis in conventional DNA sequencing.
With reference to FIG. 3, the sample processing components include an autosampler 40 , valve means 42 for controllably adding an appropriate solution of matrix from containers 44 to each sample, and a pump or other flow system 46 for transferring liquid samples from a selected sample to a known sample position on the sample plate. The sample plate is precisely located on a holder mounted on a computer-controlled x-y table 48 . Each sample position may be computer recorded at the time the sample aliquot is transferred to the plate. The autosampler may be similar to autosamplers used with capillary electrophoresis.
FIG. 3 illustrates one embodiment of a suitable system 30 for preparing and processing samples. Samples are presented to the system in standard sample vials, such as small plastic Eppendorf Tubes 33 . A large number of samples tubes may be accommodated within a sample input tray 34 . The person providing the samples enters sample ID information in computer 36 , selects the dilutions and matrixes required, and sets the internal standards and relative concentrations, if required, for each sample. The system prepares the requested sample dilutions and matrix and standard additions, and transfers each sample aliquot to a known position on the sample plate 10 discussed above. The computer 36 generates a data file containing sample ID, dilution, matrix, and internal standard (if any) for each position on the sample plate. The sample plate from transporter 50 is capable of automatically changing the sample plate when it is filled, and transporting the filled sample plate to a cassette 54 for sample drying and storage. Each plate is identified with a bar code and both the sample preparation system and the MALDI instrument are equipped with bar code readers for automatic sample tracking. Individual sample plates or cassettes containing up to 20 sample plates may be transferred along with the sample data to the MALDI instrument for analysis. The computer controlling the sample preparation system is networked with the computer (shown in FIG. 8) controlling the mass spectrometer, so that both sample information and mass spectral data may be exchanged between the two computers. The samples accordingly may be prepared in one laboratory and the data processed there, even if the MALDI instrument is in a different location. This feature also allows multiple sample processing and loading stations to be used with a single mass spectrometer.
4. Drying and Storing Sample Plates
When each sample location on a plate has been loaded with a sample, the samples are allowed to dry before the plate is transferred into the vacuum chamber of the mass spectrometer. In the simplest case, the plates may be transferred from the sample loading system to a rack or cassette where they are allowed to dry in laboratory air. In the preferred embodiment, however, this rack or cassette 54 is located inside a sealed chamber 52 equipped with a computer-controlled door 56 which allows the samples to be dried in an environment in which the pressure, temperature, and composition of the surrounding atmosphere is controlled. In the fully automated mode, each of the loaded and dried sample plates may be transferred from the sample plate storage chamber 52 to an adjacent mass spectrometer. Alternatively, the samples may be prepared and loaded off-line onto the sample plates. When a sufficient number of sample plates has been loaded with samples, the plurality of sample plates may be transferred manually to the mass spectrometer and loaded as a complete cassette using the manually operated sample loading door.
5. Transferring Sample Plates into the Mass Spectrometer Sample Receiving Chamber
The manual step involved in loading the sample plates may be eliminated by adding a sample storage region to the vacuum lock chamber of a mass spectrometer, as shown schematically in FIGS. 4 and 5. This provision, when coupled with on-line sample loading, allows the system to be operated in a fully automatic, unattended mode. In this configuration, an input door 58 is located between the vacuum lock chamber 68 and the storage chamber 60 . An air cylinder transporter 89 equipped with electromagnets is provided for transporting sample plates 10 from the transport tray 80 within the storage chamber 60 to the vacuum lock chamber 68 . The tray or cassette 80 contains multiple shelves and corresponding slots each for storing a sample plate. A cassette transport device mechanism including a lead screw 64 driven by a stepper motor 66 is provided to allow any selected one of these slots and a corresponding plate 10 in the cassette 80 to be brought into line with transporter 89 .
The system as shown in FIGS. 4 and 5 allows sample plates 10 to be loaded into the storage region of the vacuum lock chamber 68 , while another sample plate 10 is being analyzed in the ion source chamber 74 of a mass spectrometer. In fully automatic operation, whenever a new sample plate 10 may be loaded, the storage chamber 60 is evacuated, the input door 58 between the storage chamber 60 and the vacuum lock chamber 68 is opened, and the new sample plate is automatically moved by transporter 89 to a sample transport tray 87 provided in the vacuum lock chamber 68 . The input door 58 is then closed and the vacuum lock chamber 68 remains evacuated. The plate 10 positioned by sample transport tray 87 is moved within chamber 68 by an air cylinder transport mechanism 78 .
When analysis of the samples on one plate 10 within the ion source is completed, the plate 10 is ejected and placed in a vacant slot in the sample storage cassette 80 . This cassette 80 is then moved by stepper motor 66 and lead screw 64 to bring a new sample plate in the transport tray 80 in line with the transporter 89 , and the new sample plate is loaded. The exchange of samples may thus be accomplished without venting of the vacuum lock chamber 68 , which was evacuated during the time that the samples on the previous plate were being analyzed. This allows sample plates to be changed very quickly (at most a few seconds) while maintaining the ion source at high vacuum.
The sample storage chamber 60 is equipped with a manually operated door 70 through which a number of sample plates loaded with samples that are off-line can be introduced simultaneously. To load a set of samples, a “manual load” setting is selected on the computer 36 . This causes the sample storage chamber 60 to be vented to atmosphere via vent valve 72 , and allows the manual load door 70 to be opened. The samples are then loaded and the chamber evacuated. The entire set of sample plates can now be analyzed automatically without further operator intervention.
6. Automated Vacuum Lock System
The vacuum lock chamber 68 is equipped with computer controlled valves and mechanical transport devices which allow the sample plates 10 to be transported under computer control from the sample storage chamber 60 (which may be at atmospheric pressure) to the sample receiving stage within the evacuated ion source chamber 74 of a mass spectrometer, without venting the evacuated chamber 74 . The vacuum lock chamber 68 has an input port which may be opened or closed by door 58 and through which sample plates are loaded from the sample storage chamber 60 into the vacuum lock chamber 68 . An output port through which a sample plate is transported from the vacuum lock chamber 68 to the ion source vacuum chamber 74 is similarly opened and closed by output door 76 . Each door includes an “O” ring seal and may be opened and closed by a respective air cylinder 75 controlled from the computer 107 .
A preferred embodiment of the vacuum lock chamber 68 is depicted in FIG. 5 with its associated valves and transporters suitable for fully automated operation. A cassette 80 containing a number (typically 20 ) loaded sample plates 10 may be transferred from either an off-line sample storage chamber or a sample storage chamber 60 attached to the vacuum lock chamber and thus the mass spectrometer. Before loading a sample plate 10 into the storage chamber 60 for subsequent analysis by the mass spectrometer, it may be assumed that the sample loading doors 58 and 76 are closed, the vent valve 72 is closed, and the pumpout valve 82 connecting the mechanical vacuum pump 85 with the vacuum lock chamber 68 is closed. The pumpout valve 86 connecting the mechanical vacuum pump 85 with the storage chamber 60 is first opened, thus evacuating the sample storage chamber. When the residual pressure in this chamber 60 has reached a predetermined acceptable vacuum level (e.g., 20 millitorr), the valve 82 is opened, and the input and output doors 58 and 76 are opened, allowing sample plates to be transported between the sample storage chamber 60 and the ion source chamber 74 of the mass spectrometer without significantly degrading the vacuum of the mass spectrometer. A conventional vacuum pump 96 is provided for maintaining the chamber 74 at a desired pressure. Once transport of a plate 10 is complete, the doors 58 and 76 may be closed by computer control. The fully automatic operation of the vacuum lock involves the cycle steps which begin with completing the measurements on the previous sample plate, and end with beginning the measurements on the next sample.
A simplified version of the vacuum lock designed for use with remote sample storage chamber is shown schematically in FIGS. 6 and 7. This system is suitable for manually loading individual sample plates into the mass spectrometer without venting the mass spectrometer vacuum system. Prior to loading a sample plate, it may be assumed that the output door 76 A is closed, and the pumpout valve 82 A is closed. The vent valve 72 A is opened allowing the pressure in vacuum lock chamber 92 to be raised to that of the surrounding atmosphere while the vacuum pump 96 A attached to the ion source chamber 97 maintains the ion source chamber under high vacuum. The input door 98 is then opened and the sample transport tray 99 is transported by its air cylinder 78 B through the input door 98 to a point where it is accessible for loading. The sample plates 10 may be manually loaded into the sample transport tray 99 . Under computer control following a command from the operator, the tray 99 containing a sample plate is retracted into the vacuum lock chamber 92 by air cylinder 78 B, and the input door 98 is then closed. The vent valve 72 A is then closed, and the pumpout valve 82 A is opened and the pump 84 A activated until the vacuum lock chamber 92 is sufficiently evacuated. When a satisfactory pressure has been reached (typically 50 milliliter), the output door 76 A is opened.
With reference now to FIG. 7, the sample plate 10 is then transported from the transport tray 99 to the sample receiving stage, i.e., the ion source chamber 97 , of the mass spectrometer. This transport is accomplished by energizing a small electromagnet 102 attached to the actuator rod 104 of the air cylinder 89 A. When energized, this electromagnet 102 engages the strip of magnetic material 20 attached to the sample plate 10 and firmly holds the plate 10 until the magnet is de-energized. After the sample is in place in the sample receiving stage 94 of the mass spectrometer, the magnet 102 is de-energized and the transporter cylinder 89 A is retracted, leaving the sample plate 10 in the chamber 97 . The output door 76 A is then closed and the mass spectrometer is ready for testing the new samples on plate 10 . The complete loading operation takes less than one minute, and very little gas is introduced into the ion source vacuum chamber during this operation.
To eject the sample plate and load a new one the process is reversed. First the output door 76 A is opened, and the transport cylinder 89 A equipped with the electromagnet 102 is extended so that the electromagnet makes contact with the magnetic strip on the sample plate 10 . The electromagnet is energized and the cylinder 89 A retracted to move the sample plate from the ion source chamber 97 to the transport tray 99 in the vacuum lock chamber 92 . The output door 76 A is closed, the magnet 102 is de-energized, the input door 98 is opened, and the sample tray 99 extended so that the old sample plate can be removed by the operator and replaced with a new sample plate. Except for this final step, the entire operation is accomplished entirely under control of computer 107 with no intervention from the operator except for selecting a an “eject” setting on the computer to remove a sample, and an “operate” setting to load a new sample and begin the test.
Operation of the fully automated system shown in FIGS. 4 and 5 is thus similar to the system shown in FIGS. 6 and 7 except that operator intervention is minimized in the FIG. 4 system. A preferred system according to this invention combines the features of the systems discussed above. FIG. 8 discloses a system 108 for analyzing a plurality of samples and includes an additional electromagnetic transporter 89 B which transports sample plates from cassette 80 A containing vacant sample plates 10 to the sample loading system 30 . After loading, the sample plates 10 are transported by transporter 89 B to the sample storage chamber 60 . The cassettes discussed above may each hold up to 20 sample plates in a vertical stack. The cassette 80 which supplies plates 10 to the ion source chamber has at least one empty slot when a sample plate is being tested in the ion source chamber 74 . The position of this cassette in the storage chamber may be controlled by a computer driven stepper motor as described above so that any selected slot in the storage cassette can be brought into the plane defined by the respective sample plate transporter 89 . A tested sample plate may be transported from the ion source chamber to a vacant slot in the cassette within the vacuum lock chamber, and the sample cassette indexed to position another sample plate for transport from the vacuum lock chamber to the ion source chamber, then the sample door closed and the new samples on the new plate tested. While the mass spectrometer is testing one sample plate, new samples may be manually or automatically loaded and/or tested using sample plates removed without interfering with the mass spectrometer or it vacuum system. Computer 107 controls the mass spectrometer and the position of the system components described above.
7. Sequentially Testing Loaded Sample Plates
A preferred embodiment of the ion source 110 and a MALDI mass spectrometer 112 is depicted in FIG. 9. A stainless steel block 118 is rigidly mounted to an x-y table 114 via electrically insulating posts 116 made of ceramic or polyamide. The block 118 and table 114 may be positioned within the ion source chamber 74 (or 97 ) discussed above. An electrical potential of up to approximately 30 kV, positive or negative, may be applied to block 118 by a connection to an external power supply 115 . The x-y position of the block 118 is controlled by one or more stepper motor driven mircometer screws (not shown) conventionally used with x-y tables. The block 118 is equipped with standard lip-type guide plates 121 to assist in transporting the sample plate 10 into position on the face 117 of block 118 . Conventional securing members, such as spring loaded balls 119 may be used to cooperate with the holes 14 in the plate 10 to lock the sample plate into position with respect to the block 118 .
With computer control of the stepper motors, this system allows any selected point on the sample plate to be positioned precisely (typically within one thousandth of an inch) on the optic axis of the mass spectrometer where it is irradiated by the laser beam 136 . Beam 136 strikes a sample on plate 10 at point 120 within plane 117 , resulting in ion beam 134 . Accordingly ions may be produced from each sample on the plate 10 , which is moved automatically by the x-y table 114 between sample positions with respect to the laser beam.
The remaining components of a suitable time-of-flight mass spectrometer 112 as shown in FIG. 9 include a metal plate 124 having a grid hole 122 therein, and a metal plate 128 having a grid hole therein. The metal plate 128 may be maintained at ground potential and voltages applied to block 118 and plate 124 may be varied to set the accelerating electrical potential desired, which is typically in the range from 15,000 to 50,000 volts. A suitable voltage potential between block 118 and plate 124 is 10,000 volts, and a suitable voltage potential between plate 124 and plate 128 is from 10,000 to 40,000 volts.
Most of the low weight ions are prevented from reaching the detector 140 by deflection plates 130 and 132 , which may be spaced 1 cm. apart. Plate 130 may be a ground potential. Plate 132 receives a square wave pulse timed as a function of the laser beam striking a particular sample. Each pulse thus suppresses low mass ions, so that substantially only desired ions reach the detector 140 . Other details with respect to a suitable spectrometer are disclosed in U.S. Pat. Nos. 5,045,694 and 5,160,840.
8. Automatically Adjusting Laser Intensity and Sample Position
In MALDI, the intensity and quality of the mass spectra generated is strongly dependent on the intensity of the plume of ionized and neutral material that is produced by the incident laser pulse impinging on the sample and matrix. This intensity depends on the laser intensity, the composition of the matrix used, and details of the crystalline structure of the matrix and sample on the surface. While it is possible to establish a narrow range of laser intensities which produce acceptable spectra, one typically cannot preduct with the desired precision the laser intensity which will yield the best results on a particular sample. In general, if the laser intensity is too high, the signal-to-noise ratio may be excellent, but the mass resolution and mass accuracy is degraded. Conversely, if the laser intensity is too low, the mass resolution and accuracy are satisfactory, but the signal level is low and signal-to-noise ratio is poor. Also, the surfaces of multiple samples on a plate tend to be non-uniform, so that some locations yield excellent results and others do not. Under normal control of the laser beam and sample position, it is possible through a process of trial and error to find a combination of laser intensity and sample position which provides excellent results.
An automatic control used according to this invention closely mirrors what is generally the most successful strategy when operating manually. The intensity of the beam output 136 from the laser source 148 is increased until the ion signal suddenly appears at a relatively high setting. At this point, signal-to-noise is excellent, but resolution is poor. As the laser intensity is decreased, the signal may actually increase at first (sometimes going into saturation), but at some lower intensity the signal is decreased, and the resolution is dramatically increased. With an improved attenuator 138 , this hysteresis appears to be entirely related to changes in the sample properties, and is not due to hysteresis in the attenuator. The upper and lower values for these events are very reasonably reproducible and appear to depend primarily on the particular matrix used, and only weakly on the sample preparation, source voltage, or other parameters.
The strategy for exploiting these observations in the automatic mode follows. The upper and lower limits in the acquisition set-up menu and the laser step size are established. Two choices are provided for the number of spectra to be average: an upper number and a lower number. The upper number of spectra are averaged when the laser beam 136 is at its maximum intensity, and the lower number is used at all other laser intensities.
When a new sample is selected by the autosampler menu, the acquisition starts with the laser beam 136 set at the upper limit. The number of spectra requested is averaged. If a spectrum acquired contains intensity within the desired mass and intensity limits set, the spectrum is saved and calibrated using the upper calibration file associated with this set-up file. If the spectrum acquired is too intense, i.e., the maximum intensity within the mass window is greater than the upper intensity level (typically set just below saturation), the laser intensity is decreased by one increment and the process repeated until a spectrum meeting the selection criteria is obtained or the lower limit is reached. If the spectrum is too weak, i.e., the maximum intensity within the mass window is too weak, the sample is incremented to a new spot and the process is repeated. If a spectrum is obtained which has intensity within the chosen limits at any laser intensity other than the lower limit, that spectrum is saved as an upper intensity spectrum and the upper calibration file associated with the acquisition set-up file is used. If an acceptable spectrum is obtained at the lower limit of laser intensity, that spectrum is saved as a lower intensity spectrum and the lower calibration file associated with the acquisition set-up file is used. If both an upper and a lower intensity spectrum are obtained on the selected sample spot, the acquisition proceeds to the next sample. If only one of these is obtained, or neither one, the sample is incremented to a new spot until both an upper and a lower spectrum have been saved, or until the range of possible sample spots has been exhausted.
9. Automatically Calibrating the Mass Axis
During automatic operation of the MALDI instrument, an automatic procedure may be used for checking the calibration of and recalibrating the mass scale to maintain the desired mass accuracy. This can be accomplished by loading a sample plate containing one or more known samples so that the known mass spectrum can be used to automatically check and correct the mass scale as necessary.
The procedure for calibrating the mass axis is described below. Each acquisition set-up file must have both an upper and a lower calibration file associated with it. These files may be chosen from a list of files already in existence by the operator preparing the set-up file, or may be generated using the “calibrate” selection in the set-up file for calibration based on a selected known sample. Each calibration file which is saved may have all of the parameters associated with its generation saved, so that in the event the operator chooses a calibration file which employs different parameter values, a warning is given and the acquisition set-up file corresponding to the one that was used may be displayed with the parameters highlighted that are different from those which have been selected in the new acquisition set-up. The operator has the option of approving the chosen calibration file which is then associated with the new set-up file, even if some parameters are different. Alternatively, the operator may reject the chosen calibration file, return to the set-up file, and either choose a different calibration file or generate a new one. If a new calibration file is generated using a particular set-up file, a “check replace” selection may be employed to determine if the file is to replace a pre-existing calibration file. A new designation for upper or lower calibration numbers is also an option.
In addition to the above changes in the manual calibration procedure, an automatic calibration mode may be used. Particular samples on the sample plate may be identified as calibration samples, and the calibration compound selected from a list. For each sample or calibration compound, the matrix from a list may be selected. For each calibration compound and matrix combination chosen, a list of masses and laser intensities may be stored. The normally used mass and intensity valves values may be entered as an initial equipment set-up. A service technician will be able to alter initial factory data at the location of the customer.
During automatic calibration, the procedure for acquiring the calibration spectrum is the same as for acquiring data from a sample. If the calibration designation is selected in the autosampler set-up, that sample is treated as a calibration sample and the spectrum obtained is compared to that expected from the reference file. If peaks are found within the default values of mass and intensity (typically set by the service technician), the calibration file for the particular acquisition set-up and laser intensity being used is re-computed, and the old file replaced by the new file. If the observed spectrum falls outside the default limits, a warning message is momentarily displayed and then stored for later display when the data are processed. If the attempted calibration does not succeed, the old value is retained, and automatic acquisition proceeds. For instrument service purposes, it may be desirable to retain the old calibration files in a directory accessible to the service technician.
To implement the above, columns may be added to the autosampler set-up menu. These columns might include a choice of sample or calibrant, a choice of matrices from a pull-down list, and a pull-down menu showing the list of known calibrants. The operator may also enter new parameters characterizing a new calibrant within another column. The operator may also have the option of designating a matrix choice in the acquisition set-up file.
10. Automatically Interpreting the MALDI Mass Spectra
Mass spectra interpretation depend on the type of samples analyzed and the information required. The first step is to convert the observed time-of-flight spectrum into a mass spectrum, i.e., a table of masses and intensities for all of the peaks observed in the time-of-flight spectra. Peaks that are known to be due to the matrix or other extraneous material will normally be deleted from this list. This mass spectrum is obtained by calculating the centoid and integral intensity of each peak. The peak width may also be included (e.g., full width at half maximum) to provide a measure of the maximum uncertainty in the mass determination.
In the application to DNA sequencing, each set of four samples consists of one sample ending, so that all possible fragments ending in a specific base are included in each sample set. Accordingly, for each DNA fragment to be sequenced, there is a sample with all possible fragments terminating in C, T, A, and G, respectively. Each of these fragments is observed as a peak in the time-of-flight spectrum of that sample. By superimposing the four spectra, the sequence of bases can be read directly. Furthermore, the mass difference between any pair of peaks in these four spectra must correspond to the total mass associated with the nucleotides in that portion of the sequence. This provides a significant redundancy in the results, which may be useful for analysis other than that involving the simple ordering of the peaks, a feature which is not available in electrophoresis. If a peak is very weak and is missed, or if two peaks are insufficiently resolved, a base may be missed by simple ordering. The mass difference observed between the next pair of adjacent peaks will thus show the error and allow correction. The computer may thus interpret the spectra and directly produce the sequence of bases in the DNA fragment. If there are any regions of the spectrum where the results may be consider considered ambiguous or unreliable, e.g., because the observed mass differences are inconsistent, those regions may be flagged so that the operator may perform either manual study or further automated analysis on those regions.
According to the technique of this invention a MALDI mass spectrometer is used rather than electrophoresis separation for DNA sequencing. Until recently, the MALDI technique was limited to single-stranded DNA fragments up to about 50 bases in length, but the range has now been extended to fragments as large as 500 bases in length.
Conventional large-scale sequencing is currently being done at a rate approaching 1 Mb per year of finished sequence. The cost of sequencing is in the vicinity of one U.S. dollar per base. A rate of 500 Mb per year is required for the Human Genome Project. A price of 20 cents per finished base is commensurate with the budget and goals of this project.
At the present stage of development, MALDI analysis of DNA fragments can be done readily on mixtures containing components less than 50 bases in length. Recent work suggests that this fragment length can be extended, perhaps as much as one order of magnitude to fragments 500 bases in length. Large scale sequencing would proceed much more rapidly by this technique if the fragments analyzed could be extended significantly. A reasonable goal is to be able to accurately analyze mixtures containing oligimers up to 300 bases in length. The resolution and sensitivity of presently available instruments is satisfactory. Even with the limitations imposed by the short segments, the MALDI technique with application of the present invention could be competitive with conventional approaches.
The present invention can readily handle at least 4 samples per minute, which corresponds with 50 base fragments to 50 bases of raw data per minute, since 4 separate samples are required to sequence each segment. A single instrument can run at least 1200 minutes per day to provide 60,000 bases per day of raw sequence. This is about 22 Mb/year from a single instrument. This is raw data, however, and the piercing together of fragments from short sequence generated data is likely to require considerable redundancy. Nevertheless, a single instrument, even with the limitations imposed by short segments, can surpass the total output of present conventional sequencing. The price for this instrument is about $200,000, and it should have a useful life of at least 5 years. Total cost for operating and maintaining the instrument (including amortization) should be less than $100,000/year. If the instrument produces 2 Mb of finished sequence/year, this corresponds to 5 cents/base. 250 such instruments would be required to provide sequences at the rate required by the Human Genome Project. If the length of the fragments analyzed can be extended, the speed will increase and the cost will rapidly decrease since less redundancy will be required. If the fragment length was increased to 300 bases, the raw data rate increases proportionally to about 120 Mb/year. The ratio of this raw rate to finished data rate should improve dramatically and may approach 50 Mb/year for a single instrument. In this case, ten instruments could provide the rate required by the Human Genome Project at a cost of 0.2 cent per base. Although this rate would not include the cost of sample preparation and data analysis, the rate and cost of raw sequence determination would no longer be the limiting feature.
It should be understood that this invention has been disclosed so that one skilled in the art may appreciate its features and advantages, and that a detailed description of specific components and the spacing and size of the components is not necessary to obtain that understanding. Many of the individual components of the mass spectrometer are conventional in the industry, and accordingly are only schematically depicted. The foregoing disclosure and description of the invention are thus explanatory, and various details in the construction of the equipment are not included. Alternative embodiments and operating techniques will become apparent to those skilled in the art in view of this disclosure, and such modifications should be considered within the scope of the invention, which is defined by the following claims. | The system for analyzing multiple samples includes a plurality of portable of sample supports each for accommodating a plurality of samples thereon, and an identification mechanism for identifying each sample location on each of the plurality of sample supports. The mass spectrometer is provided for analyzing each of the plurality of samples when positioned within a sample receiving chamber, and a laser source strikes each sample with a laser pulse to desorb and ionize sample molecules. The support transport mechanism provided provides for automatically inputting and outputting each of the sample supports from the sample receiving chamber of the mass spectrometer. A vacuum lock chamber receives the sample supports and maintains at least one of the sample supports within a controlled environment while samples on another of the plurality of sample supports are being struck with laser pulses. The computer is provided for recording test data from the mass spectrometer and for controlling the operation of the system. | 8 |
TECHNICAL FIELD
This invention relates to data processing systems, and more particularly, to data processing systems capable of executing floating point operations.
BACKGROUND OF THE INVENTION
Shifting of a large number of bits is typically required in data format conversions, cordic approximations and denormalization operations. The term "sticky bit" is a term commonly associated with an IEEE standard for binary floating point arithmetic where a "sticky bit" is the result of a logical OR of any bits which are discarded as the result of a right shift operation of a data operand. Such a shift operation is commonly performed when aligning two operands for floating point addition or subtraction. Detection of any bits having a logic one value which are shifted off from the resulting operand is valuable information which can be used to improve the precision of an instruction commanding a floating point unit to add or subtract two operands in floating point format. In particular, the sticky bit is used to determine whether or not the resultant operand should be rounded up in order to retain precision. Previous floating point units have used a large bit-size data shifting circuit to perform a right shift operation on the smaller of two operands. Subsequent to the shifting, a microcode software sequence is executed by a floating point unit to determine whether or not any of the bits shifted away from the smaller operand had a logic one value, thereby detecting the existence of a sticky bit. The microcode sequence is a multiple step sequence which significantly slows the floating point unit and is therefore undesirable.
Shown in U.S. Pat. No. 4,864,527 issued to Peng et al. and entitled "Apparatus and Method for Using a Single Carry Chain For Leading One Detection and For `Sticky` Bit Calculation" is a hardware implementation of detecting a sticky bit in floating point processors. Logic circuitry is associated with each operand fraction position resulting in a significant propagation delay when large bit size operands are used. In addition, a large amount of logic circuitry and time is required to implement sticky bit detection when operands in the sixty-four bit range and greater are used and each bit position is implemented with its own circuitry in a serial architecture.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide improved sticky bit detection and shifting circuitry for use in floating point arithmetic calculations.
Another object of the present invention is to provide an improved method and apparatus for use in adding or subtracting numbers in floating point format.
Yet another object of the present invention is to provide an improved physical layout of a circuit for performing both sticky bit detection and bit shifting to implement a floating point arithmetic calculation.
In carrying out the above and other objects of the present invention, there is provided, in one form, a method and circuit for implementing a sticky bit detection and an operand bit shifting function. The circuit comprises a plurality of data input terminals for receiving an input operand having a first predetermined number of bits, and a plurality of control terminals. Each control terminal receives a control signal defining a second predetermined number of bit positions of the input operand which are to be shifted. A first circuit portion is coupled to both the plurality of data input terminals and the plurality of control terminals, for providing an output signal indicating the detection of any bit having a logic one value within the second predetermined number of bits. A second circuit portion is coupled to the first circuit portion and to the plurality of data input terminals and control terminals. The second circuit portion provides a shifted output data operand derived from the input operand by shifting the first predetermined number of bits the second predetermined number of bit positions. The output detect signal is provided within a time period required to provide the shifted output data operand.
These and other objects, features, and advantages, will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates in partial schematic form a known data shifting circuit;
FIG. 2 illustrates in partial schematic form a circuit for detecting existence of sticky bits when a data operand shifting operation occurs; and
FIG. 3 illustrates in partial schematic form a circuit which concurrently performs the functions of the circuits of FIGS. 1 and 2.
DETAILED DESCRIPTION OF THE INVENTION
Shown in FIG. 1 is a known data shifting circuit 10 for shifting bits of a data operand by a controlled number of bit positions. For ease of illustration, an eight-bit implementation utilizing N-channel transistors is shown. Data shifting circuit 10 generally comprises an input portion 11, a controlled shift portion 12 and an output portion 13.
In the illustrated form, eight bits of an input data operand are respectively inputted into eight input terminals of input portion 11. Controlled shift portion 12 has an array of transistors which form ranked rows and columns of transistors. Each column and row which is formed has either a predetermined number of transistors or a single transistor. In the illustrated form, eight rows of transistors are provided corresponding in number to the number of bits of the input data operand. Nine columns of transistors are formed which corresponds in number to the number of bits of the input data operand plus one. The controlled shift portion 12 is connected to the output portion 13 at each of terminals 15-22. Nine shift control signals labeled "Shift 0" thru "Shift 8" are connected to controlled shift portion 12. The shift control signals control a shift of bits of the input data operand by a predetermined number of bits depending upon which shift control signal is asserted. Output portion 13 has eight precharge transistors which each precharge transistor respectively precharging an input of a predetermined one of eight inverters to a high logic value so that each data output of output portion 13 is initialized to a logic low.
In operation, the precharge signal is selectively asserted to initially force all output terminals to a logic low. After the input data operand is presented to input portion 11, a single one of the nine shift signals is asserted in controlled shift portion 12. The transistors of controlled shift portion 12 are configured so as to effectively implement either no shift or a shift of up to eight bits as indicated by all logic zeroes at the output terminals. When no shift occurs, the input data bits are physically coupled thru the controlled shift portion 12 and outputted by output portion 13 so that the output bits directly correspond to the input bits as labeled in FIG. 1. When a bit shift, of four bits for example, occurs the controlled shift portion 12 functions to physically route the most significant input bit, data bit 7, down four bit positions to the "Data Out Bit 3" position. In such an example, the less significant data bits which are shifted off the output data operand do not appear at the outputs of output portion 13. In this example, data input bits 3, 2, 1 and 0 are never physically connected to output portion 13 at terminals 19, 20, 21 and 22, respectively, via controlled shift portion 12. Therefore, an input data operand is readily shifted a controlled number of bit positions.
As shown in FIG. 1 it should be readily apparent that the functionality of the columns and rows of data shifting circuit 10 results in a circuit structure which does not lend itself to a compact size and layout. In particular, there is a large amount of unused area within the transistor array forming controlled shift portion 12. Controlled shift portion 12 of data shifting circuit 10 has some fixed width, W, between the multiple inputs of input portion 11 to the multiple outputs of output portion 13. As the transistor array within controlled shift portion 12 is implemented laterally from left to right, a substantial amount of unused circuit area is created in the transistor array. As illustrated in FIG. 1, the unused circuit portion is approximately fifty percent of the transistor array of controlled shift portion 12. As bit size implementations are increased, the layout and size inefficiency only becomes more critical. Further, a potential solution for minimizing the unused area by trying to wrap some of the circuitry around into the unused portion is not generally a viable solution in large bit implementations. In such a proposed alternative, increased complexity in additional routing and physical layout results from moving transistors of one column into another column for size compacting reasons makes efficient useage of the empty array impractical. Testing and manufacturing costs also increase when transistor array circuitry is nonuniform in structure. As a result, when data shifting circuit 10 of FIG. 1 is implemented in a semiconductor material such as silicon, many transistor "holes" or absences exist in the array control portion 12 resulting in a mask layer which does not even visually appear to be efficiently utilized. An additional disadvantage associated with the structure of data shifting circuit 10 worth noting is the fact that there is uneven loading associated with each shift control signal line in controlled shift portion 12. As a result, driver circuitry which can handle varying current drive requirements must be provided.
Shown in FIG. 2 is a sticky bit detection circuit 30 for detecting the presence of any sticky bits in a portion of a data operand which is shifted off of the resulting shifted data output operand. For purposes of convenience, an eight-bit implementation is again illustrated. Detection circuit 30 generally has an input portion 31, a control portion 32 and an output portion 33. Input portion 31 has a plurality of input terminals, each of which is connected to an input of an inverter, not numbered. An output of each inverter is connected to control portion 32. Each input terminal receives a predetermined bit of an eight-bit data operand as illustrated in FIG. 2. Control portion 32 has an array of N-channel transistors which form rank ordered rows and columns. As illustrated, each row of transistors from top to bottom has one more transistor in the row than the row immediately above. Each transistor of control portion 32 has a gate connected to a predetermined one of a plurality of shift control signals. In the illustrated form, nine shift signals are provided for an eight-bit implementation so that a shift of anywhere in a range of from no bits to eight bits may be implemented. In the illustrated form, a source of each N-channel transistor of each row of the array is connected together. All sources of each row's transistors are respectively connected together and to one of a plurality of inputs 36-43 of output portion 33. Output portion 33 has a plurality of pull-up transistors, not numbered, which are each controlled by a Precharge signal wherein each pull-up transistor is connected to a predetermined one of the inputs 36-43. Each of inputs 36-43 is respectively connected to an input of one of a plurality of inverters 45-52. A precharge transistor 54 is connected between a power supply voltage V DD and an output node 55, and has a gate connected to the Precharge signal. Each of inverters 45-52 has an output respectively connected to a gate of one of a plurality of pull-down transistors 56-63 for selectively connecting output node 55 to a ground potential. An inverter 64 has an input connected to output node 55, and has an output for providing a Sticky Bit output signal indicating the detection of a sticky bit.
In operation, sticky bit detection circuit 30 receives an input operand and a shift control signal and provides an output signal which indicates whether or not any sticky bits were detected as a result of a bit shifting operation. Initially, the Precharge signal is asserted which makes the outputs of each of inverters 45-52 have a logic low value thereby making each of transistors 56 thru 63 nonconductive. Transistor 54 is simultaneously made conductive which makes the sticky bit output signal have a logic low value. After the precharge signal is made nonassertive, eight data bits are coupled to detection circuit 30 and one shift signal is asserted. Control portion 32 functions to couple whatever bits which are actually shifted off from the data operand to be coupled to a respective inverter input of output portion 33. If any of the bits which are are shifted off of the data operand has a logic one value, output portion 33 functions to couple a ground potential to output node 55 thereby causing the sticky bit output signal to transition to a logic high. For example, when a shift of four bits occurs, the logic values of input data bits 0, 1, 2 and 3 are respectively connected to the inputs of inverters 52, 51, 50 and 49. If any of these shifted off bits has a logic one value, detection circuit 30 will indicate the presence of a sticky bit by providing the sticky bit output as a logic high signal. Hence, control portion 32 implements a first level of a distributed NOR function and output portion 33 implements a second level of a distributed NOR function. It should be noted that the sticky bit detction circuit 30 also has a large amount of circuit area in the transistor array which is not efficiently utilized. Particularly, for the same bit size implementation control portion 32 has a width W' similar in value to width W of controlled shift portion 12 of FIG. 1. In addition, due to a differing number of transistors connected to each shift control line in the transistor array of control portion 32, a different load is present on each of the shift control signal lines. The differing loads result in the need for differing drive requirements for each shift control signal.
Shown in FIG. 3 is a sticky bit detection and shifting circuit 70 which functions to shift a controlled number of bits of a data operand while automatically providing a sticky bit indication signal. Circuit 70 generally comprises a sticky bit detection portion 71 and a shifting portion 72 separated by the dashed line. Although circuit 70 is illustrated as being implemented by N-channel MOS transistors it should be readily apparent that the present invention may be implemented with other types of transistors in different electronic processes and with opposite conductivities. It should be noted that instead of having separate data and control inputs for each of the sticky bit detect and data shift functions, detection portion 71 and shifting portion 72 share the same shift control lines and input data bit lines 75-82 which are respectively buffered from input data bits 7-0 by an inverter, not numbered. Sticky bit detection portion 71 has an output section 84 with an output node 85, and shifting portion 72 has an output section 86 with a precharge control line 87. Output node 85 has an N-channel transistor 89 having a drain connected to a positive supply voltage V DD , a source connected to output node 85 and a gate connected to a Precharge signal.
In operation, the Precharge signal is connected to each of output section 84 and output node 85. The Precharge signal functions to initially place a logic high signal at output node 85 by making transistor 89 conductive. The Precharge signal also makes each of transistors 90-97 of output section 86 conductive, thereby forcing all of the data output bits labeled "7" thru "0" to a logic zero. After the Precharge signal becomes inactive, eight data bits are presented to circuit 70 and a single shift control signal is asserted. In response thereto, the input data operand is either not shifted and presented at the data outputs or shifted a controlled number of bit positions by shifting portion 72. For example, when the "shift 4" control signal is asserted, data bits 3, 2, 1 and 0 are not coupled to any of the data output terminals of output section 86 by shifting portion 72. Instead, shifting portion 72 couples input data "bit 4" to the data output terminal as output data "bit 0" thru the transistor which is at the intersection of the row of transistors defined by data "bit 4" and the column of transistors defined by the "shift 4" control signal. Concurrently, data bits 3, 2, 1 and 0 which have been shifted off of the output data operand are tested for a logic one value by detection portion 71. If any of the data bits 3, 2, 1 or 0 has a logic one value, output node 85 is caused to be pulled to a ground or logic low value by output section 84. Output section 84 performs a second level NOR function and detection portion 71 performs a first level NOR function. The present invention also may be implemented with equivalent logic such as with distributed OR functions. As a result of the functioning of output section 84, the sticky bit output signal changes logic value when indicating that a sticky bit does exist within the bits which were shifted off from the output data bits.
It should be noted that circuit 70 has the same number of data bit inputs and shift control inputs as each of circuits 10 and 30 rather than double the number. Sticky bit detection is automatically performed concurrently with the shifting operation so that no additional time is required after the shifting operation is complete to complete sticky bit detection. In addition, gate propagation delays between the data inputs and outputs are minimized, even for large bit size implementations. A very desirable improvement provided by the present invention in addition to the efficient speed performance is the minimization of area required to implement circuit 70. Shown in FIG. 3 is a width W" of the transistor array comprising both detection portion 71 and shifting portion 72. While the same scale is not implied between all three figures, the width W" is substantially equivalent in value to either the width W or width W" for the same bit size implementation. The actual amount of silicon area required to implement circuit 70 is practically equivalent to the area required to implement data shifting circuit 10. The combination of sticky bit detection and shifting by a single circuit results in a very size efficient circuit and layout. Further, unlike previous circuits, the same load exists on each of the shift control lines so that a driver circuit has a substantially constant load to drive regardless of the shift selection. The modular nature of the layout and circuitry of circuit 70 improves manufacturing testing and reliability.
While there have been described hereinabove the principles of the invention, it is to be clearly understood to those skilled in the art that this description is made only by way of example and not as a limitation to the scope of the invention. Accordingly, it is intended, by the appended claims, to cover all modifications of the invention which fall within the true spirit and scope of the invention. | A circuit which concurrently performs bit shifting for floating point arithmetic and sticky bit determination. An input data operand is presented to the circuit along with a control signal which determines the number of digit positions to be shifted. While shifting of bits occurs to provide a shifted output operand, detection of bits which are shifted off from the output operand for the presence of sticky bits occurs. A shifted output operand and a sticky bit detect signal are provided substantially concurrently. An efficient layout of the circuit significantly minimizes the area required to implement both functions. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to medicinal compositions and more particularly refers to such compositions for tear replacement therapy having products of human lacrimal gland acinar epithelia, and more specifically, growth factors or cytokines, in particular, the transforming growth factor beta (TGFβ).
2. Background Information
Aqueous tear deficiency is a common condition that in its most severe form may be associated with disabling ocular irritation, and visual morbidity due to corneal epitheliopathy and/or ulceration. The conjunctival pathology of Sjogren's Syndrome (SS), the most severe type of aqueous tear deficiency, consists of abnormal terminal differentiation with significantly reduced bulbar goblet cell densities (Pflugfelder, S. C. et al. Ophthalmology 1990;97:985-991), decreased expression of mucins by the superficial epithelium (Table I)(Pflugfelder, S. C. et al. 1994 ARVO abstracts. Invest. Ophthalmol. Vis. Sci. 1994; 34: 1692)), and aberrant expression of immune activation markers (HLA Class II antigens and ICAM I) and interleukin 6 (IL-6) (Jones, D. T. et al. Invest. Ophthalmol. Vis. Sci. (in press)).
TABLE I__________________________________________________________________________Results of Immunohistochemical Staining of Bulbar Conjunctival EpithelialCells on ImpressionCytology Specimens using Mucin-Specific Antibody L6Group Temporal Conjuctiva (% +) Inferior Conjuctiva (% +)__________________________________________________________________________Sjogren Syndrome (SS) ATD 18.2 18.2Non Sjogren Syndrome ATD 66.7 88.9inflammatory MGD 77.8 88.9Atrophic MGD 77.8 100Control 100 100 SS vs Inflam. MGD p = 0.022 SS vs non SS ATD p = 0.005 SS vs Atrophic MGD p = 0.022 SS vs Inflam. MGD p = 0.005 SS vs control p = 0.001 SS vs Atrophic MGD p = 0.001 SS vs control p = 0.001__________________________________________________________________________ ATD = aqueous tear deficiency, MGD = meibomian gland disease
At the present time, biological activity of tears on the health and differentiation of the ocular surface epithelia has not been evaluated. Clinical signs and ocular surface pathologic changes in patients with aqueous tear deficiency suggest that the tears may have more than a lubricating role for the ocular surface. One of the most specific clinical signs of severe aqueous tear deficiency is staining of the conjunctival and/or cornea with the diagnostic dye rose-bengal. Recently reported experimental evidence suggests that rose-bengal staining of the ocular surface epithelia may result from lack of cell coating by normal tear constituents, predominantly tear mucins (Feenstra, R. P. and Tseng, S. C. G. Arch. Ophthalmol. 1992;110:984-993). Mucin-producing goblet cells and production of cell-membrane associated mucins by the superficial stratified epithelia are markers of terminal differentiation in the normal human conjunctiva. A marked reduction in expression of both types of conjunctival mucin has been detected in the conjunctival epithelia of Sjogren's Syndrome patients (Pflugfelder, S. C. et al. Ophthalmology 1990;97:985-991. Pflugfelder, S. C. et al., 1994 ARVO abstracts Invest. Ophthalmol. Vis. Sci. 1994; 34: 1692).
Although this may be due in part to mechanical trauma related to the reduced preocular tear film, it may also represent abnormal terminal differentiation due to lack of biologically active tear constituents. At the present time, epidermal growth factor (EGF) is the only cytokine that has been detected in human tears (van Seten, G. B. et al. Graeffe's Arch. Clin. Exp. Ophthalmol. 1989;227: 184-187). Reduced tear EGF concentrations have been reported in one patient with aqueous tear deficiency (van Seten, G. B. et al. Curr. Eye Res. 1991; 10:523-527; however, the biologic activity of tear EGF has not been evaluated.
Tear secretion by the human lacrimal gland is influenced by neurotransmitters and hormones (Dartt, D. Curr. Eye Res. 1989;8:619-636; Sullivan, D. A. The Neuro Endocrine-immune Network S. Freier, Editor. Boca Raton, Fla. 1990 CRC Press, pp 199-238). Jordan and Baum have reported that the majority of tear secretion is reflexive, resulting from sensory stimulation of the lids and ocular surface (Jordan, A. and Baum, J. Ophthalmology 1980;87:920-930). A marked reduction in neural-stimulated tear secretion is an early clinical sign in Sjogren's Syndrome (Tsubota, K. Am. J. Ophthalmol. 1991; 111: 106-108), but the clinical consequences of reduced neural-stimulated tears have not been established.
We recently discovered that the pathologic changes associated with Sjogren's Syndrome may be due in part to reduced concentrations of cytokines produced by the lacrimal gland and secreted into the tears that are essential for normal health and differentiation of the ocular surface epithelia. Based on its ability to induce differentiation of intestinal mucosa (Kurokowa, M. et al., Biochem. Biophys. Comm. 1987; 142:775-782), and corneal epithelia (Kruse, F. E. and Tseng. S. C. G. Invest. Ophthalmol. Vis. Sci. 1993;34: 1963-1976), and its ability to down regulate HLA Class II antigen and IL-6 expression (Lucas, C. et al. Ciba Foundation 1991; 157:98-114), we hypothesized that transforming growth factor beta (TGFβ) may be one of the biologically essential tear cytokines. Recently, TGF has been reported to be produced by mammary gland acini (Maier, R. et al. Mol. Cell. Endocrinol. 1991;82: 192-198) and secreted into milk.
TGFβ is a multi-functional biologically essential cytokine. TGFβ has a spectrum of biologic activity and has been reported to induce differentiation and inhibit proliferation of mucosal epithelia, including rabbit corneal epithelia (Kurokowa, M. et al. Biochem. Biophys. Comm. 1987; 142:775-782; Kruse, F. E. and Tseng, S. C. G. Invest. Ophthalmol. Vis. Sci. 1993;34: 1963-1976). TGFβ has also been reported to stimulate synthesis of extra cellular matrix components and has been shown to induce these effects on corneal stromal fibroblasts (Ohji, M. et al. Curr. Eye. Res. 1993;12:703-709). Finally, TGFβ has immunosuppressive activity that includes inhibition of T-cell proliferation, down regulation of expression of inflammatory cytokines such as IL-6 and immune activation markers such as HLA class II antigens (Lucas, C. et al. Ciba Foundation 1991; 157:98-114).
At the present time, commercially available artificial tear replacements are composed of synthetic polymers, buffers, and electrolytes in an aqueous solution. Examples of such solutions include "BION" (Alcon Laboratories, Fort Worth, Tex.) and "REFRESH PLUS" (Allersan, Irvine, Calif.). Major components of commercially available artificial tear replacement solutions, Ophthalmic lubricants which protect the eye from drying, and ocular decongestants, are listed in TABLES II, III, and IV, respectively. These solutions contain no biologically active components to modulate the health and differentiation of ocular surface epithelia. Tear replacement therapies containing biologically active components could potentially reverse pathologic ocular surface epithelial changes, and would present a great advance in treatment of severe aqueous tear deficiency states.
TABLE II__________________________________________________________________________ARTIFICIAL TEAR PREPARATIONSMAJOR COMPONENT CONCENTRATION TRADENAME PRESERVATIVE/EDTA__________________________________________________________________________Carboxy methycellulose 0.5% Cellufresh None 1% Celluvisc NoneHydroxyethyl cellulose Lyteers Benzalkonium Cl + EDTA TearGard Sorbic Acid + EDTAHydroxyethyl cellulose + Neo-Tears Thimerosal + EDTAPolyvinyl AlcoholPydroxyethyl cellulose + Adsorbotear Thimerosal + EDTAPovidoneHydroxypropyl Cellulose Lacrisert (Biode- None gradable insert)Hydroxypropyl Methylcellulose 0.5% Isopto Plain Benzalkonium Cl Isopto Tears Benzalkonium Cl Tearisol Benzalkonium Cl + EDTA 1% Isopto Alkaline Benzalkonium Cl Ultra Tears Benzalkonium ClHydroxypropyl Methylcellulose + Tears Naturale Benzalkonium Cl + EDTADextran 70 Tears Naturale II Polyquad Tears Naturale Free NoneHydroxypropyl Methylcellulose + Lacril Chlorobutanol +Gelatin A Polysorbate 80Methylcellulos 1% Murocel Methyl- + PropylparabensPolyvinyl Alcohol 1.4% Akwa Tears Benzalkonium Cl + EDTA Just Tears Benzalkonium Cl + EDTA Liquifilm Tears Chlorobutanol 3% Liquifilm Forte Thimerosal + EDTAPolyvinyl Alcohol + 1% Hypotears Benzalkonium Cl + EDTAPEG-400 + Dextose Hypotears PF EDTAPolyvinyl Alcohol + 1.4% Murine Benzalkonium Cl + EDTAPovidone 0.6% Refresh None Tears Plus Chlorobutanol__________________________________________________________________________
TABLE III______________________________________OPHTHALMIC LUBRICANTSTRADE NAME COMPOSITION______________________________________AKWA Tears Ointment (Akorn) Sterile ointment containing white petrolatum, liquid lanolin, and mineral oil.Duolube (Bausch & Lomb) Sterile ointment containing white petrolatum and mineral oil.Duratears Naturale (Alcon) Sterile ointment containing white petrolatum, liquid lanolin, and mineral oil.HypoTears (Iolab) Sterile ointment containing white petrolatum and light mineral oil.Lacri-Lube S.O.P. (Allergan) Sterile ointment containing 42.5% mineral oil, 55% white petrolatum, lanolin alcohol, and chlorobutanol.Refresh P.M. (Allergan) Sterile ointment containing 41.5% mineral oil, 55% white petrolatum, petrolatum, and lanolin alcohol.______________________________________
TABLE IV__________________________________________________________________________DRUG TRADE NAME ADDITIONAL COMPONENTS__________________________________________________________________________OCULAR DECONGESTANTSNaphazoline AK-Con* Benzalkonium Cl + edetate disodiumHydrochloride Albalon* Benzalkonium Cl + edetate disodium Clear Eyes Benzalkonium Cl + edetate disodium Degest 2 Benzalkonium Cl + edetate disodium Naphcon* Benzalkonium Cl + edetate disodium Opcon* Benzalkonium Cl + edetate disodium Vasoclear Benzalkonium Cl + edetate disodium Vasocon Regular* Phenylmercuric acetatePhenylephrine AK-Nefrin Benzalkonium Cl + edetate disodiumHydrochloride Efricel Benzalkonium Cl + edetate disodium Eye Cool Thimerosal + edetate disodium Isopto Frin Benzalkonium Cl + edetate disodium Prefin Liquifilm Benzalkonium Cl + edetate disodium Relief -- Tear-Efrin Benzalkonium Cl + edetate disodium Velva-Kleen Thimerosal + edetate disodiumTetrahydrozoline Collyrium Benzalkonium Cl + edetate disodiumHydrochloride Murine Plus Benzalkonium Cl + edetate disodium Soothe* Benzalkonium Cl + edetate disodium Tetracon Benzalkonium Cl + edetate disodium Visine Benzalkonium Cl + edetate disodiumDECONGESTANT/ASTRINGENT COMBINATIONSNaphazoline Clear Eyes ACR Benzalkonium Cl + edetate disodiumHydrochloride (Allergy/Coldplus Zinc Sulfate Relief)Phenylephrine Prefrin-Z ThimerosalHydrochloride Zincfrin Benzalkonium Clplus Zinc SulfateTetrahydrozoline Visine A.C. Benzalkonium Cl + edetate disodiumplus Zinc Sulfate__________________________________________________________________________ *Prescription medication
SUMMARY OF THE INVENTION
We have recently been able to culture human lacrimal gland acinar epithelia which secrete proteins typically produced by lacrimal gland secretory acini in vivo (Yoshino, K. et al., Proceedings of the Fourth International Symposium on Sjorgren's Syndrome (1993), p. 804). In addition, we have evaluated human tears for TGFβ using the CCL-64 mink lung epithelial cell (MLEC) growth inhibition assay and sELISA. Results indicate that human lacrimal gland acini produce and secrete TGFβ into the tears, and that there are factors in human tears capable of binding TGFβ.
It is therefore an object of the present invention to provide cultured human lacrimal gland acinar epithelia as a model of in vivo secretory acinar function. These cultures can be used for testing of agents which stimulate or inhibit tear secretion and the analysis of biologically active tear constituents that are secreted by the lacrimal gland which can be used for the treatment of diseases affecting the ocular epithelia. Specifically, diseases of the ocular surface associated with aqueous tear deficiency.
It is another object of the present invention to provide a medicinal formulation suitable for the treatment of various conditions which result in tear deficiency or ocular irritation. Conditions benefiting from physiologic tear replacement include patients with lacrimal gland dysfunction, destruction or surgical removal (Sjogren's Syndrome, post radiation, altered innervation, surgical removal for treatment of tumor).
It is yet another object of the invention to provide tear replacement compositions containing TGFβ which are more effective than the composition presently in use which do not contain biologically active components. According to the present invention, tear replacement compositions are provided by adding TGFβ to a pharmaceutical composition for application to the eye in order to lubricate the eye or to supplement tears.
According to the present invention, tear replacement compositions as stated above may also contain any or other components produced by lacrimal gland epithelia, naturally present in human tears such as antimicrobial proteins (for example lactoferrin and lysozyme), retinol binding protein (for example tear specific pre-albumin), biologically active components or cytokines such as epidermal growth factor, or retinol.
Compositions according to the present invention can be used to treat aqueous tear deficiency and conditions associated with alterations of the ocular suface epithelia including hyperproliferation, squamous metaplasia, loss of goblet cells, and abnormal terminal differentiation among other ocular surface pathologic changes that lead to ocular irritation.
The foregoing and other objects, advantages and characterizing features of this invention will become apparent from the following description of certain illustrative embodiments of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A. Expression of TGFβ1 mRNA in normal human lacrimal gland biopsies and cultured human lacrimal gland acinar epithelia. PCR products of the appropriate size (161 bp) from amplification of cDNA prepared from human lacrimal gland epithelial cultures (lane 1) and human lacrimal gland biopsies (lane 2-4) with TGF-β1 specific primers were noted on an ethidium bromide stained agarose gel (upper figure) and Southern hybridization (bottom figure). Lane 5 contains TGF-β1 cDNA. Lane 6--blank, Lane 7--molecular weight standards.
FIG. 1B. Expression of TGFβ2 mRNA in normal human lacrimal gland biopsies and cultured human lacrimal gland acinar epithelia. A PCR product of approximately 450 bp was noted on an ethidium bromide stained agarose gel of amplification of cDNA prepared from human lacrimal gland epithelial cultures (lane 1) and human lacrimal gland biopsies (lanes 2-4) with TGF-β2 specific primers. On Southern hybridization, three hybridizations signals with approximate sized of 350-, 450-, and 500-bp were obtained from cDNA prepared from cultured lacrimal gland epithelia (lane 1) and one lacrimal gland biopsy (lane 2), while only two hybridization bands (350 and 450 bps) were obtained from cDNA prepared from the other two lacrimal gland biopsies (lanes 3 and 4). Multiple sized PCR products are most likely due to alternate splicing of the region of the TGF-β2 gene amplified with these primers. Lane 5 contains TGF-β2 cDNA. Lane 6--blank, Lane 7--molecular weight standards.
FIG. 2A. Expression of TGFβ1 and TGF2 protein in normal human lacrimal gland biopsies. (a) majority of tubuloacinar structures in all five human lacrimal gland biopsies showed immunoreactivity to a polyclonal antibody to all isotypes of TGF-β (pan TGF-β Ab, 40× original magnification). (b) Absence of immunoreactivity to TGF-β2-specific antisera was noted in all lacrimal gland biopsies (400× original magnification). (c) and (d). TGF-β1-specific antibodies produced strong immunoreactivity with epithelial cells in four or five lacrimal gland biopsies. The strongest staining with TGF-β1 antibodies was noted in the apical secretory portion and lumens of acinar epithelial complexes ((c)--100×, (d)--100× original magnification). (e) and (f). In sections where entire Tubuloacinar structures were visualized (asterisk), TGF-β1 staining appeared stronger in acinar than ductal epithelia ((e) imunofluorescent staining, (f)--phase, 100× original magnification).
FIG. 2B. Expression of TGFβ1 and TGFβ2 protein in cultured human lacrimal gland acinar epithelia. The cytoplasm of cultured human lacrimal gland epithelia stained with both TGF-β1 (top figure) and TGF-β2 (bottom figure) antisera (100× original magnification).
FIG. 3. Results of ELISA for TGF-β1 and TGF-β2 in supernatants (spnt) from human lacrimal gland acinar epithelial cultures and control media. TGF-β1 [] in culture supernatants were significantly greater than media or TGF-β2 (*0.169 ng/ml±0.021)in culture supernatants (P<0.05)
FIG. 4. Growth inhibitory effects of native human tears in mink lung epithelial cell bioassay.
FIG. 5. Concentration of TGFβ in native tears treated with various physicochemical techniques.
FIG. 6. Growth inhibitory effects of human tears following acidification or treatment with n-acetylcysteine ("MUCOSIL™", DEY Laboratories, Napa, Calif.) and heating.
FIG. 7. Effect of TGFβ isotype specific neutralizing antisera on antiproliferative effects of human tears.
FIG. 8. Results of ELISA for TGF-β1 and TGF-β2 for human tears. TGF-β concentration in tears is 0.521 ng/ml+0.321. Tear TGF-β1 concentrations were significantly greater than TGF-β2 (P<0.05).
FIG. 9. Western blot of native tears treated with n-acetylcysteine and heating, showing pro-TGF-β binding to high MW complexes (about 1000 kD, probably mucins), and monomeric TGF-β. Lane 1 purified TGF-β1. (R&D), monomer band is present at approximately 12.5 kD (arrowhead); Lane 2. blank; Lane 3. native tears--a high molecular weight band (approximately 100 kD asterisk) is noted; lanes 4-6: tears treated with n-acetylcysteine and heating (lane 4), acidification with HCl (lane 5), and acidification followed by reduction with DTT (lane 6). Two bands of immunoreactivity were noted with these specimens, a stronger band at approximately 110 kD, the size of the pro-TGF-β complex (LAP plus cytokine, star) and a weaker band of the same size as monomeric TGF-β (approximately 12.5 kD. arrowhead)
DETAILED DESCRIPTION OF THE INVENTION
In accordance with the present invention, tear replacement compositions containing TGFβ, where TGFβ is either TGF-β1 or TGF-β2 or a combination thereof, by way of non limiting illustration, be applied to the eye in animals and humans as a drop or within ointments, gels, liposomes, or biocompatible polymer discs or pellet. They can be attached to, carried by and/or contained within contact lenses that are placed on the eye. In general, it is desired that the mode of application be such that the composition enters the tear film or otherwise makes contact with the surface of the eye.
Further in accordance with the invention, a replacement tear composition is made by combining TGFβ with a physiologically acceptable carrier. Preferably, the preparation will be unit dose, refrigerated, with or without preservative. The composition may also contain a physiologically compatible ophthalmic vehicle as those skilled in the art can select using conventional criteria. The vehicles may be selected from the known ophthalmic vehicles which include but are not limited to water, polyethers such as polyethylene glycol 400, polyvinyls such as polyvinyl alcohol, povidone, cellulose derivatives such as carboxy methylcellulose, methylcellulose and hydroxypropyl methylcellulose, petroleum derivatives such as mineral oil and white petrolatum, animal fats such as lanolin, vegetable fats such as peanut oil, polymers of acrylic acid such as carboxylpolymethylene gel, polysaccharides such as dextrans and glycosaminoglycans such as sodium hyaluronate and salts such as sodium chloride and potassium chloride, calcium chloride, magnesium chloride, zinc chloride, and buffer such as sodium bicarbonate or sodium lactate. High molecular weight molecules can also be used, such as mucins.
Preferred preservatives are physiologically compatible and do not inactivate TGFβ or other peptides or cytokines present in the composition. Preservatives include but are not limited to alcohols such as chlorobutanol, and benzalknonium Cl and EDTA, though other appropriate preservatives known to those skilled in the art may be used.
In a preferred embodiment, the concentration of TGFβ in the tear solution is from 250 pg/ml to 12.5 ng/ml, preferably 200 pg/ml to 12.0 ng/ml. Active TGFβ concentrations in human tears range from 250 pg/ml to 12.5 ng/ml (mean 3.83 ng/ml). There appears to be a total latent TGFβ concentration of approximately 30 ng/ml in tears. Ideally, therapeutic TGFβ should be administered bound to its natural carrier or binding protein(s) in tears. At the present time, these appear to be mucins because immunoreactivity of TGFβ in native tears is at a high molecular weight (approximately 1000 kD), the molecular weight of tear mucins. Data suggests that most TGFβ in tears is in the proform (approximately 110 kD). Typically, this proform is converted to the active from by proteolytic enzymes such as plasmin. Plasminogen activator is normally found in human tears. It is likely that concentrations of this protein are reduced in patients with aqueous tear deficiency. Therefore, it may be necessary to use purified (lyophilized) active TGFβ. The source of this cytokine is not essential. It could be purified from platelets (a rich source of TGFβ1) or recombinant TGFβ could be used. Alternatively, cultured lacrimal gland acini could serve as the source of TGFβ. Other lacrimal gland produced tear constituents which may be desirable to add to physiologic tear replacements include, lactoferrin, 1-3 g/L (Kijlstra, A. et al. (1983), Br. J. Ophthalmol. 67:199-202), lysozyme, 0.5-4.5 g/L, and Tear specific pre-albumin, 0.5-1.5 g/L (Berman, E. R. Biochemistry of the Eye, Ed. C. Blakemore, Plenum Press, New York, 1991), mucins, and epidermal growth factor (EGF) 0.75-9.7 ng/ml (van Setten, G. B. et al. (1989) Graeffe's Arch. Clin. Exp. Ophthalmol. 22:184-187; Ohashi, Y. et al. (1989) Invest. Ophthalmol. Vis. Sci. 30:1879-1882), and Vitamin A, 16 ng/ml of retinol (Vitamin A is present in tears as retinol but would need to be added to tear replacement as trans retinoic acid) (Ubels, J. L. and Mac Rae, S. M. (1984) Current Eye Res. 3:815-822).
The following examples are presented to illustrate further various aspects of the present invention, but are not intended to limit the scope of the invention in any respect.
EXAMPLE 1
Production of TGFβ by Human Lacrimal Gland Epithella
We have recently evaluated normal human lacrimal gland biopsies and cultured human lacrimal gland acinar epithelia (Yoshino, K. et al. Sjorgren's Syndrome--Proceedings of the Fourth International Symposium, 1993. Ed. M. Homma, S. Sugai, T. Tojo, N. Miyasajka and M. Akizuki, Kugler Publications, 1994, Amsterdam/New York) for expression of TGFβ1 and TGFβ2 mRNA and protein using RT-PCR, sELISA and immunohistochemisty, techniques known in the art (Ji, Z. et al. Invest. Ophthalmol. Vis. Sci. (1994 ARVO abstracts) 1994; 34: 1792). TGFβ1 and β2 mRNA expression was found in both lacrimal gland biopsies and acinar cultures (FIGS. 1A and 1B). In lacrimal gland biopsies, immunoreactivity to TGFβ1 but not TGF-β2 was detected in the secretory portion of the lacrimal gland acinar epithelia adjacent to the lumen by immunohistochemistry (FIG. 2A). The cytoplasm of cultured acinar epithelia showed immunoreactivity to both TGFβ1 and β2 specific antisera (FIG. 2B). TGFβ1 was detected in supernatants of lacrimal gland acinar cultures in significantly greater concentrations (0.5-2 ng/ml) than the control (culture media on substrate) by sandwich ELISA (sELISA, FIG. 3). Furthermore, stimulation of cultured human lacrimal gland acini with 0.01 mM carbachol (a cholinergic agonist) resulted in at least a 30% increase in TGFβ1 concentrations in the supernatants. These experiments indicate that TGFβ is produced and secreted by human lacrimal gland acinar epithelia, and that this secretion may be enhanced by cholinergic stimulation.
EXAMPLE 2
TGFβ in Human Tears
We recently evaluated human tears for TGFβ using the CCL-64 mink lung epithelial cell (MLEC) growth inhibition assay, a conventional assay for the detection of TGFβ, and sELISA (Danielpour D. et al. (1989) Cell Physiol. 138:79-86). Native human tears produced an anti-proliferative effect in the MLEC assay; however, a flat growth inhibition curve with rapid loss of anti proliferative activity after 3 to 7 serial dilutions was noted with native tears (FIG. 4). Heating and acidification, two physicochemical techniques previously reported to activate latent TGFβ increased the concentration of TGFβ in human tears calculated at the midpoint of the growth inhibition curves (FIG. 5). Furthermore, incubation of human tears with n-acetylcysteine ("MUCOCIL"™, DEY Laboratories, Napa, Calif.), a mucolytic and reducing agent, followed by heating at 80° C. for 8 minutes appeared to release latent TGFβ in tear samples, compared to tears treated by heating alone (FIG. 6). Following this treatment, a growth inhibition curve with a slow decay of the growth inhibition activity as tear specimens were serially diluted was obtained that resembled the curve obtained with serially diluted purified human platelet TGFβ1 (FIG. 6). The anti-proliferative effect of human tears in the MLEC assay could be inhibited by pre-incubation with TGFβ1 neutralizing anti-sera but not by TGFβ2-specific antisera (FIG. 7).
The presence of TGFβ in human tears was confirmed by TGFβ1 sELISA. TGFβ1 was not detected in native tear samples by sELISA; however, pre-treatment of human tears with n-acetylcysteine followed by heating resulted in an average detectable tear TGFβ1 concentrations of 45 ng/ml (range 19.99-67.7 ng/ml). TGFβ2 was detected in human tears by sELISA at very low concentrations (521 pg/ml with a range of 316-891 pg/ml) compared to TGFβ1 (p<0.05).
SDS-PAGE and immunoblotting experiments were performed to confirm the molecular weights (MW) of TFGβ complexes in human tears.
EXAMPLE 3
Western Blot Analysis
Western blots were preformed as follows. Kaleidoscope pre-stained molecular weight standard was purchased from Bio-Rad (Richmond, Calif.). Human platelet TGFβ1, rabbit anti-pan isotype TGFβ was purchased from R&D Systems, Inc. Anti-rabbit and anti-goat IgG-POD were purchased from Boehringer Mannheim (Indianapolis, Ind.).
Fresh human tear specimens were activated by the following methods: (1) heating at 80° C. for 7 minutes and immediately placed on ice; (2) diluted 1:1 with 10% N-acetylcysteine "MUCOCIL"™, DEY Laboratories, Napa, Calif.) then heated at 80° C. for 7 minutes and immediately placed on ice, (3) acidification by adjusting pH to 2 with 1N HCl and incubating at room temperature for 1 hour. The pH was then neutralized with one NaOH, (4) acidification, then reduction by addition of 5 ul of 1M dithiothreitol (DTT). All activated specimens were then added to 2× sample buffer and boiled at 100° C. for 3 minutes.
Mini-protein II 4-20% Ready gels were used for SDSpolyacrylamide gel electrophoresis (SDS-page) and were purchased from Bio-Rad. Running buffer contained Tris/glycine with SDS. Electrophoresis was performed at constant voltage (125 V) in a Bio-Rad mini-protein II electrophoresis cell until the dye marker had reached the bottom of the gel. Electrophoretic transfer on to PVDF membrane (Millipore, Beford, Mass.) was performed with a Bio-Rad Trans-Blot cell. Transfer buffer consisted of glycine/ethanolamine and 20% methanol. Prior to transfer, the PVDF membrane was pre-wet in 100% methanol, rinsed with distilled water and immersed for 15 minutes in buffer. Transfer was performed at 20 V overnight. After electroblotting, membranes were stained with Pouceu S (Sigma) for 2 minutes, then rinsed with water and air dried.
Immunodetection was performed using a Bio-Rad chemiluminescent detection kit. The PVDF membrane was wet with 100% methanol, then rinsed with distilled water. The membrane was then incubated for 1 hour in blocking solution (1% blocking reagent in TBS) on a shaking incubator. The membrane was then incubated for one hour with primary antibody diluted in 0.5% blocking solution. Dilution of Pan-TGFI3 antibody was 1:2000 (1 μg/μl). The membrane was then washed twice in TBST for 10 minutes each, then washed twice with 0.5% blocking solution. The membrane was then incubated for 1 hour with POD-conjugated secondary antibody diluted 1:1000 in 0.5% blocking solution. The membrane was then washed four times with TBST for 15 minutes each. Excess buffer was then drained from the washed membrane, and it was placed in a staining dish and incubated for 30 minutes at room temperature with a mixture of solutions A and B (diluted 1:100 and incubated for 30 minutes at room temperature prior to addition). Approximately 125 μl/cm sq. was added to the membrane container and incubated for 1 minute. The wet membrane was immediately placed into a plastic hybridization bag and the bubbles were removed. The membrane (protein side up) was placed into a film cassette against a sheet of X-ray film (X-Omat, Kodak, Rochester, N.Y.) and was exposed for 1 minute, then developed. Either no immunoreactive bands or high MW bands. (>50,000 kD) were observed in native or heat treated tears. Treatment of tears with n-acetylcysteine and heating, HCl, or HCl plus DTT resulted in immunoreactive bands at 110 kD, and 12.5 kD using TGFβ specific antisera (FIG. 9). These bands correspond to the published MWs of pro-TGFβ complexes and monomeric TGFβ.
Taken together, these results indicate than native human tears contain a small amount of biologically active TGFβ (approximately 3.8 ng/ml), and a greater amount of latent TGFβ that can be released by a variety of physiochemical techniques. TGFβ1 is the predominant isoform in tears. Our finding of TGFβ1 production by human lacrimal gland secretory acini coupled with the previously reported relative lack of immunoreactivity of human ocular surface epithelia for TGFβ (Pasquale, L. R. et al. Invest. Ophthalmol. Vis. Sci. 1993;94:23-30) (only superficial limbal epithelia were positive) suggests that some, if not the majority, of TGFβ in human tears may be produced by the lacrimal gland. | The present invention relates to medicinal compositions and more particularly refers to such compositions for tear replacement therapy having products of human lacrimal gland acinar epithelia, and more specifically, growth factors or cytokines, in particular, the transforming growth factor beta (TGFβ). | 0 |
The U. S. Government has non-exclusive rights in this invention pursuant to Contract Number F19628-85-C-0002, awarded by the U.S. Air Force.
The present invention relates generally to signal nulling, and more particularly, to a matrix updating, folded linear systolic array of processors for use in a nulling system.
BACKGROUND OF THE INVENTION
Antennas, such as radar antennas, are subject to receiving both desired and undesired signals, where the latter may degrade the performance of the system of which the antenna is a part. An antenna suitable for interference cancellation may be treated as a combination of many individual antenna elements, each antenna element receiving a particular combination of wanted and unwanted signals. In fact, it is known to sum the signals of all antenna elements, giving appropriate weight to appropriate elements. Furthermore, it has been demonstrated that if the appropriate statistics are gathered, it is possible to determine the optimum weights to be applied to particular signals in order to optimize reception of the desired signals by nulling out the undesired signals. A problem arises, however, in the implementation of any weighting system, since it will require substantial computation to determine the best weights unless the number of antenna elements is a very small number.
More particularly, assume a system where an antenna has N antenna elements Each antenna element, as for example, antenna element j, receives a signal which may comprise a desired signal and/or any number of undesired signals in some linear combination, where the total unwanted signal on antenna element j is p j . The collection of undesired signals o all the N antenna elements forms a vector P. Of course, it should be appreciated that the order in which each antenna element is numbered is completely arbitrary. However, once such an order has been established it should be consistently followed since it determines the order of signals in the vector P.
Naturally, P and all its components p j are functions of time. Samples of p j are obtained from time to time, with the signals on all the antenna elements sampled at the same instant. If the n-th sample on the j-th antenna element is p j (n) and the collection of all the samples at the same instant is P(n), then P(n) has N components and the component which originated as a sample from antenna element-j is the j-th component of P(n). Because of the way signals on antennas are often sampled, each of the components is generally a complex number, having a real part and an imaginary part. If n is the number of the most recent sample available, then P(n) is the current vector of observations of unwanted signals.
In many mathematical treatments of the behavior of arrays of antenna elements it is useful to know a certain N×N matrix called a `correlation` matrix R, expressed as: R=E(P(n)×P t (n)), where E is understood to mean `expectation of`, and where the superscript t stands for the simultaneous operations of transposing a vector or matrix and conjugating all the complex numbers appearing as entries in the vector or matrix. In practice, an approximation to this expectation is measured using an average of P(n)×P t (n), the average being taken over the current observation vector and those which have been seen up to the present.
To explain further, if all the previous observation vectors were collected together, i.e., P(n-3),P(n-2),P(n-1), which might be a collection extending indefinitely far into the past, but not including the present observation vector, one could, from these samples, determine the `previous` correlation matrix R(n-1). Also, the current R(n) can be determined if the current observation vector, P(n), were appended to this collection of observation vectors. Furthermore, still another more up-to-date estimate of matrix R may be computed with each new observation vector appended to the last updated matrix R(n-1).
In the averaging process it is generally desired to weight the most recent observations somewhat more heavily in the statistic than the older observations. This may be accomplished by using a "forgetting factor". A forgetting factor is a number smaller than 1.0 (usually only slightly less than 1.0) which may be designated as α. Therefore, the iteration is R(n)=α 2 R(n-1)+P(n)×P t (n). Since this is an iteration, it will be understood that R(n-1)=α 2 R(n-2)+P(n-1)×P t (n-1), and so on. Therefore R(n) is influenced by all the previous observation vectors, to some extent, but because of the forgetting factor α, the influence of the older observation vectors is more and more diminished. In carrying out this iteration, it may be assumed that at some instant long ago, R(0) was a matrix of all zeros. However, since α is less than 1.0, even if R(0) were not a matrix of all zeros, after a long enough time, the current correlation matrix R(n) will eventually no longer be significantly affected by the initial state R(0).
The same information which is contained in R(n) can be carried by an N×N lower triangular matrix, where N is the number of elements, and n is the current data set. While several forms of lower triangular matrix are operable within the present invention, for purposes of expediency, discussion here is limited to operation of the invention with respect to a particular N×N lower triangular matrix L commonly referred to as the Cholesky factor. Matrix L is determined by processing the samples which have so far been collected, being updated as each sample is collected. Therefore L(n) will be understood to refer to the Cholesky factor which was computed from samples up to and including the current observation vector P(n). It will be appreciated by those skilled in the art that the Cholesky factor must observe the following relationship with L(n): R(n)=L(n)×L t (n). Also, the entries along the diagonal of the matrix L(n) must be real numbers.
To explain further, if all the previous observation vectors were collected together, i.e., P(n-3),P(n-2),P(n-1), which might be a collection extending indefinitely far into the past, but not including the present observation vector, the `previous` Cholesky factor L(n-1) would be known. If to this collection of observation vectors, the current observation vector, P(n), were appended, the current Cholesky factor L(n) could be determined. Furthermore, the current Cholesky factor can be determined using only P(n) and L(n-1), whereby each time a new observation vector P(n) is received its information is folded into the most recent L matrix (which now has become matrix L(n-1)) to create still another, more up-to-date Cholesky factor.
SUMMARY OF THE INVENTION
In one aspect of the present invention, a circuit is provided for computing from complex data the values of the elements of a triangular matrix representative of a correlation matrix of N columns and N rows, the circuit including either ##EQU2## (where N is an even number) or ##EQU3## where N is an "odd" number) subcircuits, each subcircuit having at least one CORDIC processor and a memory, the subcircuits connected in a folded systolic array, the first subcircuit of the array providing input capability to the array for receiving complex data containing N words, and the output of the last subcircuit being coupled to its own input. Each subcircuit updates and stores, based upon the complex data, the value of two complementary columns of the matrix, where generally the length of the two columns combined together is equal to N+1 words where N is even, or N words where N is odd.
In another aspect of the present invention, each subcircuit comprises a first, a second and a third CORDIC processor and memory, where the first CORDIC processor is disposed to perform a rotation upon the complex data to make the leading element of the data real, the output of this CORDIC processor being a second complex number and being applied along with a complex number from the memory to the inputs of the second and third CORDIC processors, where the real parts of the two above complex numbers are inputted to the second CORDIC processor and the imaginary parts of the two above complex numbers are inputted to the third CORDIC processor, the second CORDIC processor providing a real output and the third CORDIC processor providing an imaginary output, these latter two outputs being coupled to the input of at least one of the subcircuits of the array.
In yet another aspect of the present invention a circuit is disclosed which repetitively updates, with a continuous stream of current observation vectors, the Cholesky factor of a correlation matrix, where this matrix is based upon an average of the most current observation vector and those vectors which have been processed up to the present. Also, the vectors are effectively weighted from most recent to oldest, in favor of the most recent vector, as each new observation vector is added to update the Cholesky matrix.
In another aspect of the present invention, a supercell constitutes a special form of subcircuit provided with three CORDIC circuits associated with a single memory, where the supercells are arranged in a folded pipelined configuration such that vector data can be processed systolically. Generally, systolic processing refers to the rhythmic flow of data through a processor at each clock pulse analogous to blood flowing through a body, pulsing with each heart beat. The present invention makes use of systolic processing, but in a highly efficient configuration of supercells.
In another aspect of the invention, N/2 supercells are connected in a folded linear systolic array to enable repetitive updating of a Cholesky matrix having N columns and N rows (where N is an even number), or (N+1)/2 supercells (where N is an odd number). Each supercell is assigned computational responsibility for a particular pair of columns of the Cholesky matrix such that the combined length of any two paired columns equals N+1, when N is even, and N, when N is odd, except that where N is an odd number the lead supercell is assigned a single unpaired column of a length equal to N. A given supercell of this array will perform unitary matrix multiplications on stored data representing columns of an N row by N+1 column matrix comprising the most recently known Cholesky factor and the current observation vector, or on stored data representing intermediate results, such that the data stored in all the supercells will finally come to represent the updated Cholesky factor. In this process, information must be passed from supercell to supercell. The latency of the supercells is coordinated such that data from a supercell's next higher neighbor in a systolic array never arrives at the same time at that supercell's input as data arriving from that supercell's next lower neighbor of the array of supercells. An output may be taken from the array of supercells representing a Cholesky matrix updated with the most recent observation vector, which may be used in a subsequent computation to determine the optimum weights to be applied to the nulling circuit of a nulling processor to null out the undesired portion of signals received by the antenna of the system.
BRIEF DESCRIPTION OF THE DRAWINGS
A preferred embodiment of the present invention is described in the accompanying drawings, in which:
FIG. 1 is a block diagram of a supercell circuit of the invention;
FIG. 2 is a block diagram of a linear systolic array; and
FIG. 3 is a block diagram of a folded linear systolic array of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention provides an efficient means for computing successive matrices:
. . , L(n-2),L(n-1),L(n), where a new Cholesky factor computation begins whenever a new observation vector is presented. Furthermore, in operation, the processor is designed to update the Cholesky factor repetitively.
The basic algorithm to be used may be described by matrix algebra. At the beginning of an update cycle the previous Cholesky factor L(n-1) will be held in system memory, already multiplied by the forgetting factor α represented as: ##EQU4## The current observation vector P(n) may be represented as: ##EQU5## Next, α L(n-1) and P(n) may be appended together in a single matrix, X, with N rows and N+1 columns, as follows: X=[αL(n-1)|P(n)].
This appended matrix X is to be right-multiplied by a succession of simple matrices, Q m , with m running from 1 to 2N, where the result of each right-multiplication overwrites the contents of X, such that X←X×Q m , using 2N steps. The final result is a new Cholesky matrix L(n), with N updated rows and N updated columns.
More particularly, in the first, third, fifth, and in general all odd-numbered processing steps, the matrix Q 2k-1 (by which X is right-multiplied) is chosen such that only the last column of X, the one which is initially P(n), is changed. This column is multiplied by a complex number of the form (cos θ+i sin θ), such that Q 2k-1 has its elements given by the formulae: ##EQU6## In this case θ is chosen so that one of the numbers in the last column, called the column leader, becomes, after the multiplication, a real number. It follows that θ must be determined using knowledge of the leader. The column leader for the first step is the first number in the column. The column leader for the third step is the second number of the column. The column leader for general step m=2k-1(as k takes on successively l,2,3, . . . ,N) is the k-th element in the column.
In the second, fourth, sixth and in general even-numbered steps the matrix Q 2k (by which X is right-multiplied) is chosen such that only two of the columns of X are changed. The last column is always one of the two columns changed and the other column changed is, for the second step, the first column, for the fourth step, the second column, and, in general, for the 2k-th step (as k takes on successively l,2,3, . . . ,N) the k-th column of X is changed. Thus Q 2k has its elements give by the formulae: ##EQU7##
As a consequence of these general steps, whenever steps m=2k-1 or m=2k are carried out, both the columns of X processed by these steps are guaranteed to have only zeros prior to the numbers designated as column leaders in said columns. These zeros need not be explicitly stored or computed.
The k-th elements in both columns to be changed are designated the leaders of their columns. Let column-k of X, which came from the previous Cholesky factor, be designated L and let the other column (the last column) be designated Y. Then the matrix multiplication carried out on the 2k-th step must replace these two columns quantities by
L←α(L cos φ+Y sin φ)
Y←α(Y cos φ-L sin φ)
where the two actions are effected simultaneously. φ is such that the leader of Y becomes zero. It follows that φ must be determined from knowledge of the leaders of the two columns before the matrix multiplication can be applied to the remaining numbers making up these two columns. This algorithm is well known in the literature of mathematics. It is a modification (for handling complex numbers and for incorporating the forgetting factor) of a mathematical procedure called a Givens transformation.
The operations called for by this algorithm can be carried out using a well-known technique for digital arithmetic called CORDIC computation. A digital circuit designed to carry out CORDIC computation can accept pairs of digital numbers, say A and B, and operate on these pairs of numbers to produce pairs of output digital numbers, say A' and B'. The CORDIC circuit has two modes. In one mode of the CORDIC circuit, called rotate mode, the outputs are computed from the inputs such that
A'=A cos θ-B sin θ, and
B'=B cos θ+A sin θ.
By a trivial modification to the design of a CORDIC circuit, the multiplication by α can be included, so that
A'=α(A cos θ-B sin θ), and
B'=α(B cos θ+A sin θ).
In the rotate mode, the quantity θ is represented internally in the CORDIC circuit in the form of a set of control bits which are not changed during the rotate mode. A and B represent the real and imaginary components, respectively, of a complex number C=A+iB, where the CORDIC circuit will produce a complex output C'=A'+iB'. Hence C'=(cos θ+i sin θ)C. Again, it would be a trivial modification to include here the forgetting factor, α. In the remainder of the discussion of the CORDIC circuits, however, it will be assumed (unless otherwise specified) that the output of a CORDIC circuit can include the forgetting factor, α, even though not shown.
In the other mode of the CORDIC circuit, called setup mode, the response to inputs A and B includes setting the control bits, as well as computing outputs A' and B'. These control bits effect a rotation of angle θ for which the statements:
A'=A cos θ-B sin θ=±A.sup.2 +B.sup.2,
and
B'=B cos θ+A sin θ=0
are true. If A and B are considered to be the real and imaginary components, respectively, of a complex number C=A+iB, then the setup mode produces an output C' which is real.
In the algorithm described above, each of the 2N matrix right-multiplications may be effected by a CORDIC circuit. The function of the CORDIC circuit may be best described by reference to odd-numbered steps and then even-numbered steps. In odd-numbered steps it is desirable to multiply the last column of X by cos θ+i sin θ, where the angle θ is selected to make the designated leader of this last column a real number. In so doing, the CORDIC is first used in its setup mode, with the real part of the designated column leader sent to the CORDIC input A and the imaginary part of the designated column leader sent to CORDIC input B. After the CORDIC controls are determined which represent a suitable θ such that the leader output is a real number, all the other numbers making up this last column are processed serially by the same CORDIC processor in its rotate mode. Hence, these sequences of numbers are each multiplied by the same cos θ+i sin θ. Furthermore, in the last of these odd-numbered steps, the column will have only one element, the leader, hence it is not required to use the rotate mode this last step, such that only the setup mode of the CORDIC would be used on this last odd-numbered step.
In the above use of CORDIC circuits, it is not necessary to have a correction for the forgetting factor. However, in the interest of having a system with many identical parts, it may be adequate to use a CORDIC processor which does incorporate the forgetting factor, especially if the forgetting factor is very close to 1.0, or where the forgetting factor may be selectively applied by action of an additional control circuit.
There still remains to be discussed the even-numbered steps of the 2N matrix right-multiplications.
On the even-numbered (2k-th) steps, first the designated leaders of the two columns of appended matrix X, column k and column (N+1), are sent to the A and B inputs of a CORDIC circuit, in its setup mode, with the designated leader of column (N+1) of X directed to the B input. It will be understood, of course, that these designated leaders are real numbers, as a consequence of previous steps. The output which results has B' set to zero. The A' and B' outputs are written back into corresponding positions in X. Once the controls have been set which are an internal representation of the φ parameter, the other numbers making up the two columns being processed are presented to the CORDIC circuit in the manner discussed below.
Beginning with j=k+1 and running to j=N, the real parts of the j-th numbers in column k and column (N+1) are sent respectively to the A and B inputs of a CORDIC circuit and the A' and B' outputs are written back, respectively, into the real part storages in X from which the A and B inputs were taken. Then the imaginary parts of the j-th numbers in column k and column (N+1) are sent respectively to the A and B inputs of another CORDIC circuit which uses the same controls as were established by the setup mode and the A' and B' outputs are written back, respectively, into the imaginary part storages in X from which the A and B inputs were taken. On the last even-numbered step, the two columns processed have only one element each, the leader elements (which do not have an imaginary component), so only the setup mode is used since the rotation mode is not required.
The forgetting factor is appropriately applied to the numbers computed to replace column k. It is not appropriately applied to numbers computed to replace the tacked-on column Y, but may be included if α is close to one, in the interest of having identical circuit components.
It is to be understood that this has been a description of how a CORDIC type of circuit can do the computations called for in the above algorithm. In the present invention, CORDIC circuits are used in this way, but the use of memory is quite different.
There is a way to combine odd-numbered and even-numbered steps of the above procedure together into a single, more elaborate step. In this combined procedure, three CORDIC circuits are designated as the θ-CORDIC, the master φ-CORDIC and the slave φ-CORDIC, respectively. A complex number from the last column of the appended matrix X, say the j-th number in the column, is sent to the A and B inputs of the θ-CORDIC with its real part directed to the A input and its imaginary part directed to the B input. Some time later the corresponding A' and B' outputs are available. These are directed to the two φ-CORDICs. The A' output is directed to the B input of the master φ-CORDIC and the B' output is directed to the B input of the slave φ-CORDIC. Meanwhile, the j-th complex number in the other column of X being processed on this step is accessed and its real part is directed to the A input of the master φ-CORDIC at the same time that its imaginary part is directed to the A input of the slave φ-CORDIC. Some time later, when the A' and B' outputs of the two φ-CORDICs become available, the A' outputs of the master and slave φ-CORDICs, respectively, become the real and imaginary parts, respectively, of the j-th number in the updated column of matrix X, while the B' outputs of the master and slave φ-CORDICs become, respectively, the real and imaginary parts of the j-th number in the last column of matrix X.
The foregoing CORDIC arrangement is a modification of the standard mathematical application of Givens transformations. This modified arrangement is suited for dealing with complex data. It should now be appreciated that the first step is to deal with the single tacked-on column of complex data which is to be applied to the Cholesky lower triangular matrix L. A CORDIC processor is used on this column to make the leading element real, by use of the CORDIC setup mode applied to the leader, and the rotation mode applied to the other elements in the tacked-on column. Meanwhile, since the lead element of the k-th column of the triangular matrix is also real, the setup phase now can be applied to these two columns. This is accomplished by feeding the above real numbers to one CORDIC processor, which accomplishes the setup phase of the Givens transformation. The actual transformation of the two columns is accomplished using the two master/slave CORDIC processors, one of which works on the real parts and one of which works on the imaginary parts. These three CORDIC processors, together with storage capability, are combined to create a fundamental building block of the present invention: the supercell.
Referring to FIG. 1 a schematic diagram of a supercell 10 of the present invention is shown. It will be appreciated that the most recent observation vector P(n) is a collection of words representing observations from all antenna elements and will be inputted as a column, Y, to be tacked onto the existing Cholesky matrix. The existing Cholesky matrix and the tacked-on column form the appended matrix X, which after processing will yield the new updated Cholesky matrix L(n). The latter being the desired output of the present invention.
The tacked-on vector Y will be understood as comprising a real component indicated as signal S a and an imaginary component indicated as signal S b as applied to the inputs A and B, respectively, of CORDIC processor 12 shown in FIG. 1. As the leader of Y is presented to CORDIC processor 12 in its setup mode, it rotates the complex number A+iB of the tacked-on column, finding a real angle θ such that the lead element A'+iB of the output of CORDIC processor 12 is real. Thereafter the remaining complex numbers of the tacked-on column are multiplied by cos θ+isin θ using the rotate mode. This completes the rotation step of CORDIC processor 12 and the outputs A', B' of CORDIC processor 12 will then be applied to the B inputs of master CORDIC processor 14 and slaved CORDIC processor 16.
It should be understood that memory 18 holds the data representative of the column of the Cholesky matrix to be updated. The real component of the memory's column data, A', is applied to CORDIC processor 14 at its A-input and the memory's imaginary component, B', is applied to CORDIC processor 16 at its A-input. (Not shown in FIG. 1 is a capability of applying the fixed multiplier α to the information entering memory 18. It will be appreciated, however, that such function is preferably performed within the supercell. Hence, the internal architecture of a supercell 10 will preferably include column memory, three CORDIC processors and associated multipliers.)
By now it will be clear that the memory input to be applied to the CORDIC processors 14 and 16 represents the column of the Cholesky matrix to be updated. This data is stored in memory 18 with a gain matching the gain experienced at the output of CORDIC processor 12.
In operation, the input of the most recent vector Y to be tacked on as a new column goes to CORDIC 12, where a rotation is performed to make the leading element real. The complex number from memory 18 and the complex number from CORDIC processor 12 are now inputted to the master/slave CORDIC processors 14, 16. The real parts of each number become the two inputs to master CORDIC processor 14 and the imaginary parts are the two inputs to slave CORDIC processor 16. CORDIC processor 14 in its setup mode rotates the first arriving element (comprised of the lead element of output of CORDIC 12, which is a real number, and the lead element of the column from memory, which is a real number) in accordance with the statements:
L←(L cos φ+Y sin φ), and
Y←(Y cos φ-L sin φ),
where the two actions are effected simultaneously and where φ is such that the leader of Y becomes zero, and applies the same rotation to all its other elements in sequence.
CORDIC processor 16 is slaved (in the sense of using the same control bits) to CORDIC processor 14, and processes the imaginary outputs of CORDIC processor 12 and memory 18. CORDIC processor 14 provides the real output, S a' , of the tacked-on column as modified and the slaved processor 16 provides the imaginary output, S b' , as outputted by supercell 10.
Referring now to FIG. 2, a pipelined array 20 of N supercells 10 is shown. It will be appreciated that N supercells are shown in FIG. 2 coupled in a serial, systolic configuration whereby the most current observation vector P(n) is applied at input 22 to a first supercell 30. The output of supercell 30 is applied to the input 23 of supercell 32. The input to supercell 32 comprises N-1 words representative of the tacked-on column, as it has been modified by the first two matrix multiplications Q 1 and Q 2 . This processing continues until the last supercell 34 of the pipelined array 20 receives one word from the prior supercell 33, representative of the tacked-on column as it has been modified by multiplications Q 2N-1 and Q 2N . Furthermore, in the same manner that the memory of supercell 30 holds the "column 1" data to be updated by the newest observation vector P(n), the memory of supercell 34 holds the column data to be updated by the single word applied to this supercell.
Upon further study of FIG. 2, it will become apparent that supercell 30 will process a column having a length of N words and consequently must store a column of N words in its memory. Meanwhile, processor 34 will store only one word in its memory representative of column N, since the other N-1 words of column N are known to be always zero and need not be explicitly represented or computed. As a result, near fifty per cent efficiency would be achieved by such an array 20 if it were comprised of N identical, or substantially identical, supercells, each having a memory storage capacity of N words.
Referring now to FIG. 3, there is shown the preferred folded systolic configuration 40 of the present invention (where N is an even number). In this configuration, near 100% efficiency is achieved by pairing longer and shorter columns together such that column lengths always equal a constant, the constant being the memory length of each supercell (and equal to N+1).
More particularly, if, for example, each observation vector P(n) is comprised of 64 words per update (representing 64 antenna elements), such information is applied to a switch S1 which will direct such vector information to first supercell 44 where it is used t update the 64 words of the previous column 1 of matrix L stored in memory 45. That processed data (less one zeroed element) is sent via switch S2 to second supercell 46 to compute a new 63 word update for column 2 of the Cholesky array, storing this updated information in its memory 47 for the next-to-come update, and outputting 62 words to the next supercell 48 through switch S3.
This systolic pumping of column update information (shortened one element per supercell) continues down to the ##EQU8## supercell 49, which in this example is the 32nd supercell. Hence the update information arriving at switch S32 is inputted to the θ-CORDIC processor of supercell 49 for updating the 33 words of column 32 information stored in memory 50. This new information is now stored in memory 50 as it is outputted (shortened one element) to switch S32, and because this switch is the last switch of the array, such outputted data is returned via switch 32 to the θ-CORDIC processor of this same supercell 49 for updating the 32 words of column 33 data also stored in memory 50.
The shortened output from supercell 49 representative of updated information from column 33 is applied to the next previous supercell in the array, which continues in sequence until arriving at supercell 46 via switch S2 from supercell 48 which receives two words for update of column 63 within memory 47 of supercell 46. The shortened output from supercell 46 is one word derived from update of column 63. This single word is applied via switch S1 to the memory of supercell 44 to update that portion of memory 45 representative of column 64.
Hence, in view of the folded systolic architecture of the present embodiment, each supercell may contain three CORDIC processors and a memory comprising N+1 words of storage. Each supercell uses the entire memory of N+1 words, as a result of pairing appropriate column lengths of the lower triangular Cholesky matrix. Furthermore, it will be appreciated that while circuitry for the forgetting factor is not shown in FIG. 3, addition of such compensating circuitry may be achieved by those skilled in the art.
Also not shown is means for utilizing the present invention in a nulling system. Nonetheless, it will be understood that the contents of the memories of the supercells of the array is representative of the Cholesky factor, and may be processed in a conventional manner by another processor to yield suitable weights for nulling out the unwanted signals which have been received in an antenna of N elements of a system utilizing this invention.
It will now be appreciated that it is possible to design a supercell with CORDIC circuits configured such that new data may be presented to the A and B inputs of a CORDIC circuit several times while the first A and B input data are being internally processed. The number of `problems` being worked on by the CORDIC at once is called the latency of the CORDIC. If the time interval between when a circuit may accept new pairs of inputs, (A j , B j ), is T, and if the outputs (A' j , B' j ), emerge at the time inputs (A j+ μ, B j+ μ) are input, then μ is the latency of the CORDIC circuit.
Many digital arithmetic circuits can be designed which have latency in the sense that new problems can be begun while old problems are being processed internally. However, CORDIC circuits may be designed with an additional property relating to the setup mode and the rotate mode. The control bits which are used in the rotate mode of a CORDIC may be determined, in the setup mode, a few bits or even one bit at time. Therefore, neither the setup mode nor the rotate mode should be considered as a mode of the entire CORDIC circuit, but either is only applied to a particular (A, B) pair being processed by the circuit. It is possible, indeed common, to design CORDIC circuits so that the θ or φ parameters determined in the setup mode for a particular (A j , B j ) can be used in the rotate mode on the very next pair (A j+1 , B j+1 ) presented to the CORDIC circuit. In this invention, CORDIC circuits have been designed in this way.
Note that if the latency of a CORDIC is μ, in the supercell described above, the time for a quantity in a tacked-on column to go from the input of a supercell to its output is 2μ.tbd.τ, which is the latency of a supercell. It should be easy to see that a supercell can begin new problems involving pairs of complex numbers (quadruplets of real numbers) every T seconds, with τ such problems being started before the first quadruplet B', A', B', A' of supercell 10 emerges from its master and slave θ-CORDICs. It is only a slight complication that one pair of numbers from any quadruplet (which come from the memory) must be presented internally with a delay of μT relative to the corresponding other pair of numbers (presented at the input) in the quadruplet.
It should now be appreciated that a preferred folded systolic array of the invention will enable simultaneously employing ##EQU9## supercells to repetitively update the Cholesky factor (where N is an even number), or ##EQU10## supercells to repetitively update the Cholesky factor (if N is an odd number). For ease of discussion, only the case where N is an even number is described below, the other case involving a trivial modification.
In the preferred folded array, each of the ##EQU11## supercells has the responsibility to update repetitively two columns of the Cholesky factor. If the supercells are numbered from k=1 to ##EQU12## then supercell k has the responsibility to update columns k and (N+1-k) of the Cholesky factor. Note that these columns have exactly (N+1-k) and k words respectively, so that a total of N+1 words of memory will suffice to store the two columns in every case. All but two of these words of memory must be able to store complex numbers. Two of the words will store the respective leaders of the two columns, and these are, as earlier shown, real numbers. Generally, all supercells operate independently of one another under control of the same synchronous clock.
Because it must be able to update the first column of L(n), the first supercell must be presented with appropriate input data from P(n). The N complex numbers making up P(n) are presented to its θ-CORDIC one complex word at a time on N successive time intervals. With each complex word, the real part is presented to the A-input of the θ-CORDIC and the imaginary part is presented to the B-input of the θ-CORDIC. On the first of these time intervals, the pair are marked with a special pulse designating the first (A, B) pair of inputs as a `leader`.
Following N successive time intervals, there are b other time intervals on which no information is presented to the θ-CORDIC. b is a choice of the designer of the system and b may be zero.
Following these N+b intervals, there is an interval in which the θ-CORDIC takes its A and B inputs from the second supercell's outputs. The A input of the θ-CORDIC is taken from the B' output of the master φ-CORDIC of the second supercell and the B-input of the θ-CORDIC of the first supercell is taken from the B'-output of the slave φ-CORDIC of the second supercell. This interval is also marked with a special pulse designating the (A, B) pair as a leader. There follow b more time intervals during which the θ-CORDIC of the first supercell is presented with no information.
After the N+1+2b intervals just described, the whole process is repeated with the inputs from the next current observation vector P(n+1) in place of those from P(n). After N+1+2b more intervals, the observation vector P(n+2) is input, and so on, indefinitely.
The behavior of the k-th supercell may be described in general terms applicable for any k from k=1 to ##EQU13## However, when k=1, some of the inputs may come from the `outside world` instead of from a prior supercell. Hence, the discussion below is most easily understood if the case of ##EQU14## is kept in mind.
Beginning with the arrival, at supercell k's θ-CORDIC's A and B inputs, of an (A, B) pair, marked with a special pulse designating a leader, from the B' outputs of supercell (k-1)'s master and slave φ-CORDICs respectively, supercell k takes inputs from supercell (k-1) for N+1-k intervals, followed by b blanks As any (A, B) pair marked by a special pulse designating it as a leader propagates through a supercell, the special pulse is used as a signal to make the θ-CORDIC operate in setup mode. A pulse derived from the special pulse, with appropriate delay, is used to make the master φ-CORDIC of the same supercell use its setup mode, and the controls generated by the setup mode in the master φ-CORDIC must be generated or set up in the slave φ-CORDIC as well. There are several convenient methods which might be used to accomplish the setup of the slave φ-CORDIC with the same controls as the master φ-CORDIC. For example, the slave φ-CORDIC does no useful work when the master φ-CORDIC is in setup mode because its A and B inputs are (0, 0). Therefore, instead, it may be given the same (A, B) inputs as are given to the master φ-CORDIC during that interval--given the same inputs it must set its controls in the same manner as the master φ-CORDIC.
The memory accessible to the φ-CORDICs, from which their two A-inputs are set, is accessed one complex word at a time (except that a leader word is always real-valued). As a pair of components are presented to the A inputs of the two φ-CORDICS, a pair of outputs are created at the two A' outputs of the same φ-CORDICs and these may be written into the same locations in memory just read (although other schemes for organizing data in memory may be conceived).
The B'-outputs of the two φ-CORDICs of supercell k need to be read sometimes by supercell (k+1) and sometimes by supercell (k-1) (with two exceptions--the first supercell's output is read only by the second supercell, and supercell ##EQU15## output is read by its own θ-CORDIC's inputs and by its nearest neighbor). It is necessary for supercell k to mark some of its outputs (B' outputs of the φ-CORDICs) as leaders. Hence, by any conventional means, a special pulse marking an output as a leader is attached to the supercell output exactly τ+1 intervals after a special pulse is noted at its input.
After the arrival, at supercell k's θ-CORDIC's A and B inputs, of (N+1-k) successive (A, B) pairs from supercell (k-1) beginning with one marked as a leader, followed by b blanks, an (A, B) pair marked as a leader will be available from supercell (k+1). This will be the first of k successive (A, B) pairs, from the B' outputs of supercell (k+1)'s master and slave φ-CORDICs, respectively. These pairs are also followed by b blank intervals. Supercell k processes inputs from supercell (k+1) in the same manner as it processes inputs taken from supercell (k-1). After it has processed k inputs and b blanks, there will appear at supercell k's θ-CORDIC's A and B inputs, another (A, B) pair marked as leader from supercell (k-1), which we may consider the beginning of a new update cycle.
In order for the data arriving at supercell k from supercell (k+1) and from supercell (k-1) to never arrive at the same time at the same θ-CORDIC, it is sufficient to require that τ+1 must be an integer multiple of (N+1+2b). The system designer must see to it that this congruence is satisfied. If N is large, it will usually be appropriate to choose ##EQU16##
Each supercell in this scheme has responsibility for updating two columns of L. The memory organization of data for these two columns must be such that the correct data reaches the A-inputs of the master and slave φ-CORDICs at the correct time. This is relatively easy to assure in any of several ways. As long as each cell of the memory is read exactly N+1+2b-μ time intervals after it has been written, the contents of the memory will be self-synchronized to contain the correct data (assuming that the memory was initially all zeros or that the forgetting factor has caused all old data to become insignificant). Other memory organization schemes may be designed. For example, it is possible to use one of the special pulses marking a leader as a reset for a memory address counter.
A scheme is necessary to assure that the circuit initializes itself so that each supercell correctly chooses to read data from the previous or subsequent supercell. Several easy schemes for achieving this are possible, based on the regularity of the process, since, once they have been synchronized, each supercell alternately gets its data in blocks, originating alternately from above or from below.
There are two further considerations for application of the present invention. One is that the word-length and other parameters of the CORDIC processors and the memory making up the supercell must be adequate to give usable numerical results. The other is that some means must be provided to deliver the updated Cholesky factors, when needed, to another machine which will make use of them in some further computation. With regard to the second matter, it is important to realize that the supercells are always performing updates of their assigned columns of matrix L but that these updates at any instant of time do not all pertain to the identical current observation vector--indeed the first supercell, shortly just after it finishes accepting the last complex word from P(n) to update column 1 of L(n-1) into column 1 of L(n), must accept one word from the second supercell and begin updating its column N from a much older instance of matrix L. Nevertheless, this will not present an impediment to the skilled system designer.
While the present invention has been described with respect to the Cholesky factor, it will be appreciated that other related forms of a lower triangular matrix may be employed within the spirit and scope of the present invention. Also, the observation vectors from which the present invention computes Cholesky factors might originate from other sources than arrays of antenna elements, and the Cholesky factors computed in practice of the present invention might be used for purposes other than computing weights for a nulling system. Furthermore, several other modifications and variations of the present invention are possible when considered in the light of the above teachings. It is therefore understood that the scope of the present invention is not to be limited to the details disclosed herein, may be practiced otherwise than is as specifically described, and is intended only to be limited by the claims appended hereto: | Circuit for computing values of the elements of a triangular matrix, where ##EQU1## similar subcircuits provide CORDIC processing and memory, the subcircuits connected in a folded systolic array, the first subcircuit providing input capability to the array for receiving complex data containing N words, and the output of the last subcircuit coupled to its own input. The circuit may be used to process observation vector data taken from an antenna system of N elements to provide an output useful in determining weights for nulling out the observation data from a larger signal. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to the field of analog CMOS integrated circuit design, and specifically to integrated operational amplifiers driving low impedance loads.
2. Prior Art
A fully differential output operational amplifier is normally superior to a single ended output operational amplifier in terms of power supply noise rejection and noise coupling rejection, since the power supply variation or any noise source couples equally to both output branches at the same time and thus appears as a common mode signal not effecting the differential output of the operational amplifier. This is especially important for a mixed mode chip (integrated circuit having both analog and digital circuits on the same substrate), where the noise is generated from the switching of the digital circuits.
In the prior art, fully differential output CMOS power amplifiers are implemented using typically a two (or sometimes more) stage operational amplifier which are powered from the normal system power supply VCC. The typical two stage operational amplifier consists of a mostly differential voltage amplifying input stage for noise and offset considerations, and a current gain and/or MOS output driver stage for driving a low impedance load. These two stages both get their power from VCC. Such CMOS operational amplifiers are difficult to operate from a low voltage power supply for driving low impedance loads, such as an 8 ohm speaker, since the gate driving ability of the MOS output stage is so limited. The limited gate drive could be made up in substantial part by increasing the size of the output devices, but this could make the MOS driver prohibitively large.
Conventional enhancement mode n-MOS input stages for low voltage operation also suffer from minimum input common mode range, since the input voltage has to be at least larger than the VT (threshold voltage) of the input n-MOS. Also, conventional enhancement mode n-MOS source follower output drivers suffer from a limited swing on the output voltage in the positive direction because of the VT drop from the gate to source.
BRIEF SUMMARY OF THE INVENTION
A fully differential output CMOS power amplifier utilizing a voltage multiplying technique to provide a regulated power supply higher than the system power supply to a folded differential input stage, the bias generator, the common mode feedback circuit, and the gain/level shift stage. This allows the analog gate voltages of the output transistors to go much higher than the normal power supply, resulting in significantly reduced required size of the output transistors. Since the pump is mainly to provide for the gate voltages which require little current, it is small. In a preferred embodiment, this CMOS power amplifier is used in a mixed mode chip which already has a voltage multiplier for the on-chip memory circuit, and therefore can readily use the on-chip pump without adding another pump circuit. This power amplifier also includes a voltage regulator to regulate the multiplied voltage to a fixed level to reduce power supply variation and noise from the oscillator of the voltage multiplier.
The voltage regulator is configured in a negative feedback operational amplifier loop with diode connected p-MOS devices serving as a resistor divider to reduce the current loading to the voltage multiplier. Each diode connected p-MOS has its own well tied to its source so the VGS (gate to source voltage) of each p-MOS is precisely mirrored across the diode chain by the negative feedback action. This gives a precise voltage at the output of the regulator, in the preferred embodiment of the invention, 5 times VREF.
This fully differential output CMOS power amplifier also includes a folded cascode differential input stage utilizing native n-MOS (VT≈Ov) to give a near rail to rail input common mode range, a native n-MOS (VT≈Ov) source follower on the output stage to give a high swing voltage output, an enhancement mode n-MOS common source output stage, a mechanism for reducing crossover distortion of the output driver stage, and a scheme to set the idle current in the output drivers when the input signal is zero.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1B and 1C are circuit diagrams for the preferred embodiment of the fully differential CMOS power amplifier of the present invention, comprising FIGS. 1A and 1C, each showing one of the differential output stages, and FIG. 1B showing among other things the folded cascode differential input stage and the bias generator.
FIG. 2 is a circuit diagram for the voltage regulator used in the circuit of FIG. 1.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a circuit diagram for the preferred embodiment of the fully differential CMOS power amplifier of the present invention, using a folded cascode input stage and n-MOS transistors for the output drivers.
The preferred embodiment of the present invention is intended to be used as the output power amplifier on an integrated circuit analog signal recording and playback system such as disclosed in U.S. Pat. Nos. 4,890,259, 4,989,179, 5,220,531, 5,126,967, 5,241,494 and 5,164,915. Such integrated circuits already include a MOS charge pump voltage multiplier (the voltage multiplier 20 of FIG. 1) for other purposes, namely to provide the required high voltages for the erase and program functions for the on-chip floating gate storage cells from a single, relatively low voltage power supply to the chip, such a low voltage battery power supply providing VCC, and VSS, shown also as ground potential. MOS charge pump voltage multipliers are well known in the art, and need not be further described herein.
Also shown in FIG. 1 is a voltage regulator 22, used to regulate the multiplied voltage to reduce the voltage variation and noise coupled to the power amplifier from the charge pump, which typically has a ripple voltage on its output. The ripple period depends on the period of the pump clock generator. The ripple magnitude depends on the pumping capacitors, the magnitude of the pumping clock waveform (typically equal to VCC), the output loading current and the output loading capacitance. Even though this ripple is reduced by the power supply rejection capability of the power amplifier, it is still significant, so the voltage regulator 22 is used to reduce the ripple seen by the power amplifier. This is especially important in the idle state (when the input signal is zero), as the ripple will appear on the output as an idle noise which limits the signal to noise ratio of the power amplifier.
The fully differential output CMOS power amplifier includes a differential stage, a gain stage, common mode feedback and a bias generator, all of which get their power from the output of the voltage regulator, VCCM, a voltage significantly higher than VCC. The output stage, the only stage requiring substantial power, gets its power from the normal system power supply VCC.
The preferred embodiment of the present invention shown in FIG. 1 is intended to operate as part of an integrated circuit responsive to a power down signal to power down the circuit whenever the PD (power down) signal goes high. As the subsequent description will illustrate, the following notation is used in FIGS. 1 and 2 herein:
p-channel devices are so indicated by the circle in the gate contact, and further by the P appearing as the second letter of the device designation
n-channel devices are so indicated by the absence of a circle in the gate contact, and further by the N appearing as the second letter of the device designation
native devices are indicated by the thickened line parallel to the gate and by the letter A adjacent thereto
most devices associated with the power down function are so indicated by "PD" appearing as the third and fourth letter designations of the respective devices
In the circuit of FIG. 1, n-channel device MNPD1 and p-channel device MPPD1 are used to invert the PD (power down) signal to provide the signal PDB (PD bar or PD). Device MPPD1 is connected to VCCM instead of VCC so that PDB is VCCM when PD is zero. Thus when the circuit is enabled (PD=Ov), PDB will be equal to VCCM, completely shutting off p-channel devices MPPD2/3/4/5/5A. At the same time, PD=Ov (PD=VSS) will also completely shut off n-channel devices MNPD2/3/4. As shall subsequently be described in further detail, devices MPPD2/3/4/5/5A and MNPD2/3/4 will be turned on when PD goes high to cut off all current paths in the circuit.
Current IBIAS to the circuit is a controlled current source (actually a current sink, though the phrase current source may be used generically hereafter for source or sink, as will be obvious to one skilled in the art) mirrored from a bias current generator elsewhere in the integrated circuit, as is well known in the art. This sets the gate-source voltage of transistor MBIAS1, the input bias reference p-MOS device, to provide the basic current mirror for biases of other p-channel devices, namely devices MP6/7/8/8A/14, each therefore acting as a bias current source for various other parts of the circuit.
The bias current through p-channel device MP14 also flows through p-channel device MP13B and n-channel devices MN14, MN14A to provide biases for n-MOS current mirrors formed by n-channel devices MN11/MN11A, MN12/MN12A, MN13/MN13A of the folded cascode differential input stage, and also to provide biases for n-channel devices MN10/MN10A of the common mode feedback network. It also provides a bias for n-channel devices MN15/MN15A connected in series with diode connected p-channel device MP15 to generate a p-MOS bias for the gates of p-channel devices MP12, MP13 of the folded cascode differential input stage. p-channel device MP13B is used to force the drain-source voltage of p-channel device MP14 to be close to the drain-source voltage of p-channel devices MP7 and MP6 for more precise current matching between p-channel device MP7 and n-channel devices MN13/MN13A and between p-channel device MP6 and n-channel devices MN12/MN12A (since n-channel devices MN13/MN13A and MN12/MN12A are mirrored from n-channel device MN14, which is sinking the bias current from p-channel devices MP14).
The n-MOS cascode current mirror formed by n-channel devices MN14/MN14A uses a native (VT≈Ov) n-MOS device MN14 in series with enhancement mode n-MOS device MN14A to minimize the headroom voltage, since the bias voltage is only one gate-source voltage of the enhancement mode n-MOS device MN14A (this is in comparison with the normal two diode connected n-MOS transistors in series, which requires the sum of 2 gate-source voltages of headroom voltage). n-channel device MN14A is in saturation, since its drain voltage is close to its gate voltage. n-channel device MN14 is also in saturation since its threshold voltage is a few hundred millivolts because of the body effect. Hence, the cascoding effect is achieved with lower headroom voltage by using a native device connected in series with an enhancement n-MOS device. The native n-MOS device has its drain and gate tied together. The other n-MOS device mirrors the current to n-channel devices M10/MN10A, MN11/MN11A, MN12/MN12A, MN13/MN13A, and MN15/MN15A, which use the same scheme.
n-channel devices MN15/MN15A mirror the current from n-channel devices MN14/MN14A to p-channel device MP15 to generate the bias for the common gate connection of p-channel devices MP12 and MP13. p-channel device MP15 is sized such that the source voltages of p-channel devices MP12 and MP13 sit close to VCCM (only one drain-source saturation voltage of p-channel devices MP6 and MP7 away from VCCM) for maximum swing on the nodes OP, ON and hence on nodes OPP, ONN to optimize the size of n-channel device MN9 and MN9A.
n-channel devices MN2/MN3, p-channel devices MP6/MP7 and MP12/MP13, and n-channel devices MN12/MN12A, MN11/MN11A and MN13/MN13A constitute a folded differential native n-MOS input stage. The native n-MOS devices MN2 and MN3 are chosen for the input n-MOS pair to increase the minimum input voltage range by one enhancement mode threshold voltage and thus lower the minimum voltage input close to ground. The outputs of the folded cascode input stage on nodes OPP and ONN are differential, and are each applied to a respective single ended n-MOS output stage. In particular, when the differential inputs POS and NEG are applied to the differential input n-channel pair MN2 and MN3, the differential outputs of nodes ON and OP respond in opposite directions, in turn causing nodes ONN and OPP to follow the voltage variations of nodes ON and OP, respectively, through the common gate connected p-MOS devices MP12 and MP13. The voltages on nodes ONN and OPP are thus applied differentially to the two identical n-MOS output stages.
n-channel devices MN4, MN16, p-channel device MP8, n-channel devices MN7, MN9, p-channel device MP20, n-channel devices MN17, MN18, p-channel device MPPD5, resistor R2, capacitor C2, resistor R1 and capacitor C1 constitute an n-MOS output stage. The second identical n-MOS output stage is formed by corresponding devices having the same designations followed by the letter "A", and accordingly the description to follow is also directly applicable, though being responsive to the opposite node ONN, the opposite voltage of the differential voltages on nodes ONN, OPP. In each output stage, the capacitor is realized on-chip in integrated circuit form using techniques well known in MOS integrated circuits and MOS integrated circuit formation.
p-channel device MPPD5 is part of the shutdown circuit, and is held off (PDB high) when the circuit is not powered down (PD low). p-channel device MP20 is also related to the power down function, and is held on by PD when the circuit is not powered down. n-channel device MN7 is used in a source follower mode, and is a native n-MOS to increase the high swing by one enhancement mode threshold voltage to make the high end output OUTN swing of the output stage close to the power supply voltage VCC. n-channel devices MN4, MN16, p-channel device MPS, resistor R2, and capacitor C2 provide gain/level shift for the source follower MN7, with resistor R2 and capacitor C2 providing a compensation network for the gain/level network. Resistor R1 and capacitor C1 provide a compensation network for the final gain output stage comprising n-channel device MN9.
The output stage described above operates as follows: Assuming the signal on node OPP goes lower, n-channel device MN9 is gradually turned off, and n-channel device MN4 is also gradually turned off. p-channel device MP8 pulls the gate of n-channel device MN7 toward VCCM, and device MN7 in turn pulls the output OUTN toward VCC. Conversely, as the voltage on node OPP goes higher, n-channel device MN9 is gradually turned on, pulling the output OUTN lower. n-channel device MN4 is also gradually turned on harder, pulling the gate of n-channel device MN7 toward ground, tending to turn off device MN7 to release OUTN from the pull up effects of device MN7. Thus the output stage acts as an inverting stage.
n-channel devices MN17 and MN18 are to reduce the crossover distortion. At the mid point (analog ground, e.g. 1.5 V, or zero differential input to the system), as the voltage on node OPP goes from low to high, n-channel device MN4 is turned on, pulling the gate of n-channel device MN7 too quickly toward ground, shutting n-channel device MN7 off completely. In the meantime, n-channel device MN9 is not yet turned on, so the output OUTN is floating for a short period until n-channel device MN9 is turned on. This causes distortion. To prevent this, the voltage on the gate of n-channel device MN7 is lowered slowly to turn off device MN7 slowly by a local feedback path from the output OUTN to the gate of n-channel device MN17, which does not allow the gate of n-channel device MN7 to fall too rapidly. n-channel device MN16 acts as a resistive path to further slow down the falling of the gate of n-channel device MN7. By not allowing the gate of device MN7 to fall before device MN9 is turned on, a direct current path is created between VCC and VSS through devices MN7 and MN9 for a short period. This is the familiar tradeoff between reducing crossover distortion and increasing the direct current consumption. In that regard, n-channel device MN18, as an option, may be shorted for reducing further the crossover distortion at the expense of increasing the direct current consumption.
The idle current in the output stage (when there is no differential signal) is precisely set by the size ratio of n-channel devices MN9 to MN4 (and the bias current in n-channel device MN4, which is set by the current mirrored to p-channel device MP8). Note that the gate voltages of n-channel devices MN9 and MN4 are the same and the drain voltage of n-channel device MN9 is almost the same as the drain voltage of n-channel device MN4 by the action of source follower native n-MOS device MN7. Also because the gate of the n-channel device is allowed to swing higher than the normal power supply voltage VCC, allowing the use of a much smaller device for n-channel device MN9 (better matching between devices MN9 and MN4 because they are closer together physically), this allows the idle current to be controlled much better.
As stated before, n-channel devices MN4A, MN16A, p-channel device MP8A, n-channel device MN7A, MN9A, p-channel device MP20A, n-channel devices MN17A, MN18A, p-channel device MPPD5A, resistor R2A, capacitor C2A, resistor R1A and capacitor C1A constitute another exact replica of the above n-MOS output stage. This output branch receives its input from the ONN signal, which is differentially is always in the opposite direction to the OPP signal by the action of the input stage. Thus the output OUTP always swings in the opposite direction of the output OUTN.
The outputs OUTP and OUTN are normally connected across a speaker for driving differentially to increase the power output by four times (since the voltage swing across the speaker is doubled) as compared to a single ended power amplifier. Normally the power amplifier is used in a unity gain mode, in which case OUTP of the respective output stage is also connected to NEG input of the differential input stage.
Resistors RX1 and RX2 are common mode feedback resistors connected between the differential outputs. Their resistances are high to prevent excessive loading. The resistor network is used to sense the common mode voltage on the inputs of the power amplifier and to feed back the common mode voltage to a common mode feedback amplifier for common mode voltage correction.
n-channel devices MN1/MN1A/MN1B, p-channel devices MP10/MP10A/MP10B and n-channel devices MN10/MN10A constitute the common mode feedback amplifier. It is a conventional MOS differential amplifier with the native n-MOS transistors as the input n-MOS pair. The native n-MOS is used to increase the input voltage range as in the folded cascode input pair. The common mode input VCMD is the analog ground level (the mid point, e.g. 1.5 V in the preferred embodiment). Assuming the average of the differential outputs OUTN and OUTP is somehow higher than normal, the voltage of node CM at the resistive network junction will be higher than VCMD, causing n-channel device MN1 to turn on harder, pulling the gate of p-channel device MP10 lower, which turns p-channel devices MP10A and MP10B on harder and pulls the node OP and ON higher respectively, in turn pulling both nodes ONN and OPP higher by the common gate connected p-channel devices MP12, MP13. With the voltages of nodes ONN and OPP higher, the voltages of both nodes OUTN and OUTP go lower (the output stages of the amplifier are inverting stages), restoring the common mode voltage in the output nodes OUTN and OUTP. As the differential output OUTN and OUTP swing in the opposite direction, opposite action happens.
The folded differential input stage obtains its power from the regulated pumped output VCCM, which allows nodes ON and OP to be biased one saturation drain-source voltage VDS sat from VCCM (VCCM-VDS MP6/7sat ). This also means the voltages of nodes OPP and ONN can swing to two saturation VDSs from VCCM (VCCM-VDS Mp6/7sat -VDS Mp12/13sat ), which allows the size of n-channel devices MN9/MN9A to be small devices, even though n-channel devices MN9/MN9A have to sink a relatively huge current from the low impedance load. The level shift/gain stages (n-channel devices MN4, MN16, p-channel device MP8, resistor R2 and capacitor C2, and n-channel devices MN4A, MN16A, p-channel device MP8A, resistor R2A and capacitor C2A) get their power supply from VCCM, which allows the gate of n-channel devices MN7/MN7A to swing close to VCCM. This allows n-channel devices MN7/MN7A to be also to be small, even though n-channel devices MN7/MN7A have to source a relatively huge current to the low impedance load. The common mode feedback circuit and the bias generator also get their power supply from VCCM for proper operation.
As stated before, when the circuit is enabled (PD=Ov), PDB will be equal to VCCM, completely shutting off p-channel devices MPPD2/3/4/5/5A. At the same time, PD=Ov (PD=VSS) will also completely shut off n-channel devices MNPD2/3/4. However when PD goes high for power down, n-channel devices MNPD2/3/4 PDB will be turned on, and PDB will go low, turning on p-channel devices MPPD2/3/4/5/5A. This shuts down the various bias current sources in the amplifier and cuts off all current paths in the circuit. The turning on of p-channel devices MPPD5/5A on power down clamps the voltage of output nodes OUTN and OUTP at VCC, thereby holding the differential output at zero. Also on power down, p-channel devices MP20/20A are turned off to cut off the current path from VCC to VCCM through n-channel devices MN17/17A, MN18/18A and p-channel devices MP8/8A.
FIG. 2 is a circuit diagram for the voltage regulator 22 used in the circuit of FIG. 1. As shown in FIG. 2, an operational amplifier I1 is configured in a negative feedback loop to regulate the multiplied voltage VCCMP to a fixed level VCCM based on an input reference voltage VREF to reduce the coupling of power supply variations and noise to the power amplifier. The operational amplifier I1 used in the preferred embodiment is a conventional two stage operational amplifier. p-channel devices M1/M2/M3/M4/M5, when p-channel device M5 is on, are a series of diode connected devices, and each have their sources connected to their own well to eliminate body effect) to simulate a resistor divider of larger value resistors to reduce current loading to the voltage multiplier. In this way, p-channel devices M1/M2/M3/M4/M5 are small as compared to the large area that would be needed to realize large value resistors on-chip. In this Figure, n-channel devices MPD2 and M8 are used for power down purposes. In normal operation (PD low), n-channel device MPD2 and M8 will be off. This will hold P-channel device M5 on, activating the simulated resistor divider to feed back one fifth of the regulated voltage VCCM to the negative input of the operational amplifier. On power down when PD goes high, n-channel devices MPD2 and M8 will be turned on. n-channel devices M7/M8 are used to keep VCCM close to VCC during power down. This holds the negative input to the operational amplifier I1 high, and N-channel device MPD2 being on pull the voltage on node VCCMR to ground, turning off N-channel device M6 to decouple the output VCCM and the resistor divider from the voltage multiplier.
Thus the regulator output VCCM is regulated precisely by the negative feedback action of the operational amplifier at 5 times the reference voltage VREF, which is also 5 times the gate-source voltage of each of the p-channel devices M1/M2/M3/M4/M5 for the current flowing there through at the regulated voltage. As can be seen from the FIG., n-channel devices M6, M8 are native n-MOS devices. n-channel device M8 is to precharge the output node VCCM close to VCC, and n-channel device M7 is to keep VCCM within one threshold voltage of VCC on startup until the charge pump output VCCMP is high enough.
There has been described herein a fully differential output CMOS power amplifier that uses small output transistors for driving a low impedance load such as an 8 ohm speaker at low power supply voltages such as 2.5 volts by utilizing a stepped up voltage for a folded cascode differential input with native n-MOS devices, for the level shift/gain stage, for the common feedback network, and for the bias generator. The fully differential output CMOS power amplifier has a folded cascode differential input stage that uses native n-MOS for near rail-to-rail common mode input range, an output stage that uses native n-MOS devices in a source follower configuration for high swing efficiency, and a local feedback mechanism for reducing crossover distortion for the n-MOS output stage. A voltage regulator is provided for the stepped up voltage that uses very little current without requiring large value resistors by utilizing diode connected p-MOS transistors as a resistor divider. The n-MOS device output stage includes circuitry that accurately sets the idle current by utilizing a source follower native n-MOS to force the drain voltage of the output driver n-MOS to be almost the same as the drain voltage of a reference n-MOS device. However while a preferred embodiment of the present invention have been disclosed and described herein, it will be obvious to those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention. | A fully differential output CMOS power amplifier suitable to be used in a non-volatile memory mixed mode chip for voice record and playback to drive a very low impedance load such as an 8 ohm speaker from a low voltage power supply. This fully differential CMOS power amplifier utilizes a voltage multiplying technique for the input stage, a level shift/gain stage, and a common mode feedback network. It also utilizes native n-MOS having a threshold voltage VT≈0v for the folded cascode differential input, native n-MOS (VT≈0v) for the source follower output stage, enhancement n-MOS (VT≈0.7 v) for the common source output, and a voltage regulator using p-MOS diode connected devices for simulating a resistor divider to regulate the voltage multiplier output. The amplifier also includes a mechanism for crossover distortion reduction at the output driver stage, and a scheme to set the idle current in the output driver n-MOS transistors. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of U.S. application Ser. No. 11/936,659, filed on Nov. 7, 2007, which claims priority to and the benefit of U.S. Provisional Application No. 60/857,490, filed on Nov. 8, 2006, and U.S. Provisional Application No. 60/878,678, filed on Jan. 5, 2007, the disclosures of each of which are incorporated by reference herein in their entireties.
BACKGROUND OF THE INVENTION
At least 1 million men suffer from prostate cancer and it's estimated that the disease will strike one in six U.S. men between the ages of 60 and 80. There are more than 300,000 new cases of prostate cancer diagnosed each year. Prostate cancer will affect one in six men in the United States, and the mortality from the disease is second only to lung cancer. An estimated $2 billion is currently spent worldwide on surgical, radiation, drug therapy and minimally invasive treatments, $1 billion of the spending in the U.S. There is presently no effective therapy for relapsing, metastatic, androgen-independent prostate cancer. New agents that will enable rapid visualization of prostate cancer and specific targeting to allow radiotherapy present are needed.
N-acetylated alpha-linked acidic dipeptidase (NAALADase), also known as glutamate carboxypeptidase II (GCPII) is a neuropeptidase which cleaves N-acetylaspartyl-glutamate (NAAG) into N-acetylaspartate and glutamate in the nervous system, see below, depicting hydrolytic cleavage of NAAG by NAALDase through the tetrahedral intermediate. The enzyme is a type II protein of the co-catalytic class of metallopeptidases, containing two zinc atoms in the active site.
Independent of its characterization in the nervous system, one form of NAALADase was shown to be expressed at high levels in human prostatic adenocarcinomas and was designated the prostate-specific membrane antigen (PSMA). The NAALADase/PSMA gene is known to produce multiple mRNA splice forms and based on previous immunohistochemical evidence, it has been assumed that the human brain and prostate expressed different isoforms of the enzyme.
Human prostate-specific membrane antigen (PSMA), also known as folate hydrolase I (FOLH1), is a trans-membrane, 750 amino acid type II glycoprotein which is primarily expressed in normal human prostate epithelium but is upregulated in prostate cancer, including metastatic disease. PSMA is a unique exopeptidase with reactivity toward poly-gamma-glutamated folates, capable of sequentially removing the poly-gamma-glutamyl termini. Since PSMA is expressed by virtually all prostate cancers and its expression is further increased in poorly differentiated, metastatic and hormone-refractory carcinomas, it is a very attractive target for prostate imaging and therapy. Developing ligands that interact with PSMA and carry appropriate radionuclides may provide a promising and novel targeting option for the detection, treatment and management of prostate cancer.
The radio-immunoconjugate form of the anti-PSMA monoclonal antibody (mAb) 7E11, known as the PROSTASCINT scan, is currently being used to diagnose prostate cancer metastasis and recurrence. Early promising results from various Phase and II trials have utilized PSMA as a therapeutic target. PROSTASCINT targets the intracellular domain of PSMA and is thought to bind mostly necrotic portions of prostate tumor. 14 More recently, monoclonal antibodies have been developed that bind to the extracellular domain of PSMA and have been radiolabeled and shown to accumulate in PSMA-positive prostate tumor models in animals.
While monoclonal antibodies hold promise for tumor detection and therapy, there have been limited clinical successes outside of lymphoma because of their low permeability in solid tumors. Low molecular weight mimetics, with higher permeability in solid tumors will have a definite advantage in obtaining high percent per gram and a high percentage of specific binding.
SUMMARY OF THE INVENTION
One aspect of the present invention relates to compounds of Formula (I)
wherein R is a C 6 -C 12 substituted or unsubstituted aryl, a C 6 -C 12 substituted or unsubstituted heteroaryl, a C 1 -C 6 substituted or unsubstituted alkyl or —NR′R′,
Q is C(O), O, NR′, S, S(O) 2 , C(O) 2 (CH2)p
Y is C(O), O, NR′, S, S(O) 2 , C(O) 2 (CH2)p
Z is H or C 1 -C 4 alkyl,
m is 0, 1, 2, 3, 4 or 5
n is 0, 1, 2, 3, 4, 5 or 6
p is 0, 1, 2, 3, 4, 5 or 6
R′ is H, C(O), S(O) 2 , C(O) 2 , a C 6 -C 12 substituted or unsubstituted aryl, a C 6 -C 12 substituted or unsubstituted heteroaryl or a C 1 -C 6 substituted or unsubstituted alkyl, when substituted, aryl, heteroaryl and alkyl are substituted with halogen, C 6 -C 12 heteroaryl, —NR′R′ or COOZ further wherein
(i) at least one of R or R′ is a C 6 -C 12 aryl or C 6 -C 12 heteroaryl substituted with a halogen or
(ii) at least one of R or R′ is a C 6 -C 12 heteroaryl
or a pharmaceutically acceptable salt of the compound of Formula (I).
Another aspect of the present invention relates to compounds of Formula (Ia)
wherein R is a C 6 -C 12 substituted or unsubstituted aryl, a C 6 -C 12 substituted or unsubstituted heteroaryl, a C 1 -C 6 substituted or unsubstituted alkyl or —NR′R′,
Q is C(O), O, NR′, S, S(O) 2 , C(O) 2 (CH2)p
Y is C(O), O, NR′, S, S(O) 2 , C(O) 2 (CH2)p
Z is H or C 1 -C 4 alkyl,
m is 0, 1, 2, 3, 4 or 5
n 0, 1, 2, 3, 4, 5 or 6
n′ 0, 1, 2, 3, 4, 5 or 6
p is 0, 1, 2, 3, 4, 5 or 6
R′ is H, C(O), S(O) 2 , C(O) 2 , a C 6 -C 12 substituted or unsubstituted aryl, a C 6 -C 12 substituted or unsubstituted heteroaryl or a C 1 -C 6 substituted or unsubstituted alkyl, when substituted, aryl, heteroaryl and alkyl are substituted with halogen, C 6 -C 12 heteroaryl, —NR′R′ or COOZ
further wherein
(i) at least one of R or R′ is a C 6 -C 12 aryl or C 6 -C 12 heteroaryl substituted with at least a halogen or
(ii) at least one of R or R′ is a substituted or unsubstituted C 6 -C 12 heteroaryl or a pharmaceutically acceptable salt of the compound of Formula (I).
In a preferred embodiment of the compounds of Formulas (I), (Ia), (II) or (IIa) n is 0 or 1 and n′ is 0 or 1.
The present invention also relates to glutamate-urea-lysine PSMA-binding moieties and their use in diagnostic and therapeutic treatment. In one embodiment, the urea-based analogues described here are glutamate-urea-α or β-amino acid heterodimer coupled through the α-NH 2 or β-NH 2 groups. Radiolabels can be incorporated into the structure through a variety of prosthetic groups attached at the X amino acid side chain via a carbon or hetero atom linkage. The compounds of the present invention can find use as targeting agents and diagnostic and therapeutic agents for the treatment and management of prostate cancer and other diseases related to NAALADase inhibition.
Suitable chemical moieties, definitions of chemical moieties, excipients and methods and modes of administration can be found in US Published Application Nos. 2004/0054190 and 2004/0002478 and International Application Nos. WO 02/22627 and WO 03/060523, which are incorporated by reference in their entirety.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1A-1C are HPLC chromatograms respectively of the co-injection of the TC-99m-glu-urea-DpK (Tc-99m-MIP 1008), the rhenium analog, and the rhenium diester complexes.
FIGS. 2A-2D show stability of the Tc-99m complex of Glu-urea-DpK (Tc-99m-MIP 1008) at 37° C. in respectively PBS pH 7.2, 0.1M Cysteine in PBS, 0.1M DTPA in PBS, and 5% mouse serum in PBS for 6 hours.
FIGS. 3A-3C are respective HPLC chromatograms of N-[N-[(S)-1,3-dicarboxypropyl]carbamoyl]-S-3-iodo-L-tyrosine (I-131 DCIT) crude reaction FIG. 3A , top, purified at 2 hours, FIG. 3B , middle and at 2 days FIG. 3C , bottom.
FIG. 4A-4D are radio-HPLC chromatograms of I-131 MIP 1072 purified; at 3 days in A) DMSO. B) 3% genstisate-6% Ascorbate/Ascorbic acid, C) PBS, pH=7.2, D) 10% Ethanol in Saline at 37° C. As shown above, the I-131-1072 (peak 12 minutes) remained stable throughout the experiments.
FIG. 5 shows I-123 DCIT bound specifically to LnCap cells and not PC3 cells (left set) as is evident by the counts displaceable by nonradiolabeled compound (middle set) or PMPA (right set) in LnCap cells. The histograms show the mean±SEM, each experiment was performed in duplicate.
FIG. 6 is Scatchard Analysis in PSMA Cellular Binding Assay with cold 2-{3-[1-Carboxy-2-(4-hydroxy-phenyl)-ethyl]-ureido}-pentanedioic acid (DCT).
FIG. 7 shows biological assessments of selected compounds in the PSMA-positive LNCaP cells.
FIG. 8 show biological assessments of lead compounds in the PSMA-positive LNCaP cells.
FIG. 9 Shows Scatchard Analysis in PSMA Cellular Binding Assay with MIP1072.
FIG. 10 shows internalization of I-131-MIP1072.
FIGS. 11A and 11B respectively show stability of I-131 MIP-1072 verses DCT and Phenacetin in rat microsomes for 60 minutes.
FIG. 12 shows tissue biodistribution of the I-131 MIP1072 in xenograft tumored mice.
FIG. 13 shows inhibition of NAALADase activity from LNCaP cellular lysates.
FIG. 14 shows inhibition of NAALADase Activity from LNCaP Cellular lysates.
FIG. 15 shows inhibition of NAALADase Activity from LNCaP Cellular lysates.
FIG. 16 shows the ability of test compounds to inhibit the binding of a known NAALADase inhibitor, 131I-DCIT, to PSMA on LNCaP cells was examined. Cells were incubated with various concentrations of test compounds and 1311-DCIT for 1 hour then washed and counted to determine IC50 values.
FIG. 17 is direct binding analysis of MIP-1072. 123 I-MIP-1072 (3 nM, >1,000 mCi/μmole) was incubated with PSMA positive LNCaP cells or PSMA negative PC3 cells (300,000 cells/well), in both the absence and presence of either non-radioactive 10 μM MPP-1072 or 10 μM of a specific PSMA inhibitor (PMPA).
FIG. 18 shows saturation binding analysis of 123 I-MIP-1072 in LNCaP cells.
FIG. 19 shows internalization of 123 I-MIP-1072.
FIG. 20 shows uptake of 123 I-MIP-1072 in LNCaP xenograft bearing mice. Tissue biodistribution of 123 I-MIP-1072 (2 μCi/mouse, >1,000 mCi/μmole) was assessed in selected tissues from LNCaP (PSMA positive) tumor bearing nude mice. Results are expressed as the percent of the injected dose per gram of the selected tissues (% ID/g).
FIG. 21 Uptake of 123 I-MIP-1072 in LNCaP and PC3 xenograft bearing mice. Tissue biodistribution of 123 I-MIP-1072 (2 μCi/mouse, >1,000 mCi/μmole) was assessed in selected tissues from LNCaP (PSMA positive) and PC3 (PSMA negative) tumor bearing nude mice with (Blocked) or without (Normal) pretreatment with 50 mg/kg PMPA.
DETAILED DESCRIPTION OF THE INVENTION
Definitions
“Pharmaceutically acceptable salt” refers to those salts which retain the biological effectiveness and properties of the free bases and which are obtained by reaction with inorganic acids such as hydrochloric acid, hydrobromic acid, sulfuric acid, nitric acid, phosphoric acid, methanesulfonic acid, ethanesulfonic acid, p-toluenesulfonic acid, salicylic acid and the like.
“Alkyl” refers to a straight-chain, branched or cyclic saturated aliphatic hydrocarbon. Typical alkyl groups include methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tertiary butyl, pentyl, hexyl and the like. The alkyl group may be optionally substituted with one or more substituents selected from the group consisting of hydroxyl, cyano, or alkoxy. When the alky group is an R′ substituent, it is a lower alkyl of from 1 to 6 carbons, more preferably 1 to 4 carbons.
“Aryl” refers to an aromatic group which has at least one ring having a conjugated pi electron system and includes carbocyclic aryl, heterocyclic aryl and biaryl groups. The aryl group may be optionally substituted with one or more substituents selected from the group consisting of halogen, trihalomethyl, hydroxyl, SH, OH, NO 2 , amine, thioether, cyano, alkoxy, alkyl, and amino. Examples of aryl groups include phenyl, napthyl and anthracyl groups. Phenyl and substituted phenyl groups are preferred. “Heteroaryl” refers to an aryl group having from 1 to 3 heteroatoms as ring atoms, the remainder of the ring atoms being carbon. Heteroatoms include oxygen, sulfur, and nitrogen. Thus, heterocyclic aryl groups include furanyl, thienyl, pyridyl, pyrrolyl, N-lower alkyl pyrrolo, pyrimidyl, pyrazinyl, imidazolyl and the like.
Synthesis
All reactions were carried out in dry glassware under an atmosphere of argon unless otherwise noted. Reactions were purified by column chromatography, under medium pressure using a Biotage SP4 or by preparative high pressure liquid chromatography.
1 H NMR was recorded on a Bruker 400 MHz instrument. Spectra are reported as ppm δ and are referenced to the solvent resonances in CDCl 3 , DMSO-d 6 or methanol-d 4 . All solvents were purchased from Sigma-Aldrich. Reagents were purchased from Sigma Aldrich, Bachem, Akaal, Fisher, Alfa Aesar, Acros and Anaspec. The following abbreviations are used methylene chloride (DCM), ethyl acetate (EA), hexanes (Hex), dichloroethane (DCE), dimethyl formamide (DMF), trifluoroacetic acid (TFA), tetrahydrofuran (THF), carbonyldiimidazole (CDI), dimethylaminopyridine (DMAP), triethyl amine (TEA), methyl trifluoromethanesulfonate (MeOTf), (S)-2-Amino-6-(bis-pyridin-2-ylmethyl-amino)-hexanoic acid (dpK), glutamic acid (Glu), diisopropylethylamine (DIEA), benzyloxycarbonyl (CBZ).
Synthesis of Intermediates
The following compounds were all prepared in overall yields ranging from 20-40% following the route depicted in Scheme 1. The first step, performed at 0° C. under inert conditions used the di-t-butyl ester of Glutamic acid with CDI in the presence of base to form the intermediate Glu-urea-imidazole derivative 2. This intermediate was activated with MeOTf under basic conditions to afford the methylated imidazole 3, which under inert conditions reacted readily with amines. The tert-butyl ester protecting groups were removed using 20% TFA in DCM for 1 to 4 hour at room temperature. Upon completion of the deprotection, the reactions were concentrated on a rotary evaporator or blown dry with nitrogen and purified on a silica column or recrystallized. The final products were tested in vitro and in vivo.
L-(S)-2-[(Imidazole-1-carbonyl)-amino]-pentanedioic Acid di-tert-butyl Ester (2)
To a suspension of di-t-butyl glutamate hydrochloride (15.0 g, 51 mmol) in DCM (150 mL) cooled to 0° C. was added TEA (18 mL) and DMAP (250 mg). After stirring for 5 min. CDI (9.0 g, 56 mmol) was added and the reaction was stirred overnight with warming to room temperature. The reaction was diluted with DCM (150 mL) and washed with saturated sodium bicarbonate (60 mL), water (2×100 mL) and brine (100 mL). The organic layer was dried over sodium sulfate and concentrated to afford the crude product as a semi-solid, which slowly solidified upon standing. The crude material was triturated with hexane/ethyl acetate to afford a white solid which was filtered, washed with hexane (100 mL) and dried to afford the desired product (15.9 g, 45 mmol, 88%) as a white solid. 1 H NMR (400 MHz, DMSO-d 6 ) δ 7.63 (s, 1H), 7.00 (br, 2H), 6.31 (d, 1H), 4.02 (m, 1H), 2.19 (m, 2H), 1.86 (m, 1H), 1.67 (m, 1H), 1.39 (s, 9H), 1.38 (s, 9H). ESMS m/z: 354 (M+H) + .
Alternatively, the analogs can be prepared via the isocyanate generated in situ using triphosgene. This approach can be accomplished by either activation of the glutamate residue and coupling with a lysine residue (route A) or by activating the lysine residue and coupling it with the glutamate (route B) as shown in scheme 2 below.
L-(S,S)-2-[3-(5-Benzyloxycarbonylamino-1-tert-butoxycarbonyl-pentyl-ureido)-pentanedioic Acid di-tert-butyl Ester (3)
Route A. In a round bottom flask 1.8 mL TEA(13.2 mmol) was combined with 1.8 grams (6 mmol) L-glutamic acid di-tertbutyl ester hydrochloride in 20 mL DCM. This solution is added dropwise over 45 minutes to a solution of 10 mL DCM and triphosgene (0.7 g, 2.2 mmol) at 0° C. After stirring an additional 30 min a solution of H-lys-(Z)—O-t-butyl ester HCl (2.2 g, 6 mmol) containing TEA (1.8 mL, 13 mmol) in 15 mL DCM was added in one portion. The solution was stirred for 1 hour. The reaction is concentrated, diluted with 50 mL ethyl acetate, washed 2N NaHSO4 (2×50 mL), brine (50 mL) and dried over sodium sulfate to yield a yellow oil. Purification by column chromatography to afford the desired product as a clear oil which upon standing solidifies to a white solid (1.9 g, 54%).
Route B. In a round bottom flask triphosgene (2.9 g, 10 mmol) is suspended in DCM (50 mL) and stirred at 0° C. A solution of H-Lysine(Z) freebase (9.1 g, 27 mmol) and DIEA (10.4 mL, 60 mmol) DCM (50 mL) was added dropwise to the triphosgene solution over 2.5 hours. After 2.5 hours a solution of L-glutamic acid di-tertbutyl ester hydrochloride (8 g, 27 mmol) containing DMA (10.4 mL, 60 mmol) DCM (50 mL) was added in one portion and allowed to stir for 45 minutes. The reaction was concentrated to dryness, diluted with 150 mL ethyl acetate, washed with 2N NaHSO 4 (2×200 mL), brine (150 mL) and dried over sodium sulfate to yield a yellow oil. This oil was purified by column chromatography (SiO 2 ) to afford the desired product as a clear oil which upon standing solidifies to a white solid (12.0 g, 72%). 1 H NMR (400 MHz, CDCl 3 ) δ 7.34 (m, 5H), 5.33-5.28 (m, 3H), 5.08 (d, J=7.4 Hz, 2H), 4.38-4.29 (m, 2H), 3.15 (m, 2H), 2.32-2.01 (m, 2H), 1.90-1.50 (m, 8H), 1.43-1.40 (m, 27H, t-Bu's). ESMS m/z: 622 (M+H) + .
2-[3-(5-Amino-1-tert-butoxycarbonyl-pentyl)-ureido]-pentanedioic Acid di-tert-butyl Ester (4)
To a solution of 2-[3-(5-Benzyloxycarbonylamino-1-tert-butoxycarbonyl-pentyl)-ureido]-pentanedioic acid di-tert-butyl ester (630 mg, 1.0 mmol) in ethanol (20 mL) was added ammonium formate (630 mg, 10 eqv) followed by 10% Pd—C and the suspension was allowed to stand with occasional agitation overnight until complete. The reaction was filtered through celite and concentrated to afford the desired product (479 mg, 98%) as a waxy solid. 1 H NMR (400 MHz, CDCl 3 ) δ 7.15-6.0 (bm, 4H, NH's), 4.29 (m, 2H), 3.02 (m, 2H), 2.33 (m, 2H), 2.06-1.47 (m, 8H), 1.45-1.40 (m, 27H, t-Bu's). ESMS m/z: 488 (M+H) + .
Synthesis of the Glu-Urea-Glu Tether Core Model Compounds.
In this series a tether is incorporated onto the side chain of glutamic acid or lysine prior to conjugation to form the urea dimer. In the example below the side chain carboxylic acid of one of the glutamic acids is modified into a tether to append a chelator, atom or functional group that is or contains a radionuclide (Scheme 4).
2-{3-[3-(4-Amino-butylcarbamoyl)-1-methoxycarbonyl-propyl]-ureido}-pentanedioic acid di-tert-butyl Ester (28)
To a solution of N—BOC Glutamic acid α-methyl ester BOC-Glu(OH)-Ome (960 mg, 3.7 mmol) in DMF (6 mL) cooled to 0° C. was added EDC (845 mg, 1.3 eqv) and TEA (1.3 mL). After stirring for 10 min the mono protected diamine N—CBZ-1,4-diaminobutane hydrochloride salt (1 g, 3.8 mmol) was added and the reaction is allowed to stir overnight with warming to room temperature. The crude reaction was diluted with EA (100 mL) and washed with and washed with water (30 mL), 5% aq. Citric acid (30 mL), sat. sodium bicarbonate (30 mL), water (30 mL) and brine (30 mL). The organic layer was dried over sodium sulfate and concentrated to afford the crude product as a thick syrup (2.1 g). To the obtained syrup was added 4 N HCl in dioxane (10 mL) and the reaction was stirred at room temperature for 3 h. Concentration afforded a waxy solid (1.8 g) as the hydrochloride salt. The salt was coupled to the activated L-(S)-2-[(Imidazole-1-carbonyl)-amino]-pentanedioic acid di-tert-butyl ester (2) as described in the preceding experimental sections to afford the desired fully protected dimer x (1.9 g). This material was suspended in absolute EtOH (20 mL) excess ammonium formate (5 g) added followed by 20% Pd(OH) 2 on carbon (100 mg) and the suspension very gently agitated overnight to effect cleavage of the CBZ protection group. Filtration through celite and concentration afforded the desired free amine (1.4 g, 2.7 mmol, 73%, 4 steps). 1 H NMR (400 MHz, CDCl 3 )δ 8.41 (br, 2H), 7.36 9br, 1H), 6.44 (bs, 1H), 6.37 (bs, 1H), 4.37-4.29 (m, 2H), 3.71 (s, 3H), 3.20-1.50 (m, 16H), 1.45 (s, 9H), 1.43 (s, 9H). ESMS m/z: 517 (M+H) + .
Re(CO) 3 -2-(3-{3-[4-(Bis-pyridin-2-ylmethyl-amino)-butylcarbamoyl]-1-carboxy-propyl}-ureido)-pentanedioic Acid[Br] (29) (MIP-1100)
The protected intermediate was prepared by reductive amination using pyridine-2-carboxaldehyde as previously described. Treatment with 2M LiOH in MeOH effected hydrolysis of the methyl ester. The methanol was removed and excess DCM:TFA (1:1) was added and the reaction stirred at room temperature overnight. The crude material was converted into the desired Rhenium conjugate following the procedure described above. Preparative HPLC afforded the desired molecule (9.5 mg, 16%). 1 H NMR (400 MHz, DMSO-d 6 ) δ 8.78 (m, 2H), 8.31 (br, 1H), 7.95 (m, 2H), 7.59 (m, 2H), 7.39 (m, 2H), 6.60-6.33 (m, 2H), 4.89 (m, 4H), 4.00 (m, 1H), 3.76 (m, 1H), 3.20-1.2 (m, 16H) (3 CO 2 H not seen). ESMS 842 (M−H) + .
Synthesis of the Glu-urea-X-benzyl-Lysine Core Model Compounds.
The following compounds were all prepared in overall yields ranging from 20-40% usin the route depicted in Scheme 3. The Z-deprotected Glu-urea-lysine was mixed with the appropriate aldehyde (0.9 equivalents) at room temperature for one hour to form the □chiff base intermediate. The □chiff base was reduced using 1 equivalent of sodium triacetoxyborohydride. The compounds were deprotected using 50% TFA in DCM for 1 hour at room temperature. Upon completion, the reactions were concentrated on a rotary evaporator or were blown dry with nitrogen and extracted using methylene chloride and water. The water layer was evaporated to dryness to afford the deprotected product in 40-80% yield.
4-Trimethylstannanyl-benzaldehyde (5)
To a solution of 4-iodobenzaldehyde (1.92 g, 8.27 mmol) in dry dioxane (60 mL) was added hexamethylditin (4.1 mL, 19.8 mmol) followed by Pd(Ph 3 P)Cl 2 (150 mg) and the reaction mixture was heated for 3 h under reflux until judged complete. The reaction was filtered through celite and purified by column chromatography using hexanes/ethyl acetate (9/1) as eluent to afford (2.24 g, 98%) as a clear oil. 1 H NMR (400 MHz, CDCl 3 ) δ 9.97 (s, 1H), 7.81 (d, J=7.8 Hz, 2H), 7.72 (d, J=7.8 Hz, 2H), 0.29 (s, 9H). ESMS m/z: 268 (Sn-cluster).
2-{3-[1-tert-Butoxycarbonyl-5-(4-trimethylstannanyl-benzylamino)-pentyl]-ureido}-pentanedioic Acid di-tert-butyl Ester (6)
To a solution of 2-[3-(5-Amino-1-tert-butoxycarbonyl-pentyl)-ureido]-pentanedioic acid di-tert-butyl ester (150 mg, 0.31 mmol) in DCE (10 mL) was added 4-Trimethylstannanyl-benzaldehyde (82 mg, 0.31 mmol) followed by sodium triacetoxyborohydride (98 mg, 0.47 mmol) and the reaction was stirred overnight at 40° C. The reaction was concentrated and purified by column chromatography using hexanes/ethyl acetate as eluent to afford the desired product (88 mg, 38%) as a thick syrup which begins to solidify upon standing. 1 H NMR (400 MHz, DMSO-d 6 ) δ 7.48 (d, J=7.4 Hz, 2H), 7.30 (d, J=7.4 Hz, 2H), 6.27 (m, 2H, NH's), 3.96 (m, 4H), 2.74 (bm, 2H), 2.21 (m, 2H), 1.87 (m, 2H), 1.65-1.19 (m, 7H), 1.35 (m, 27H, t-Bu's), 0.23 (s, 9H). ESMS m/z: 742 (Sn-cluster).
(S,S)-2-[3-(5-Amino-1-carboxy-pentyl)-ureido]-pentanedioic Acid (7) (MIP 1033)
The same experimental procedure as depicted in scheme 1, yielded 8% of 2-[3-(5-benzyloxycarbonylamino-1-tert-butoxycarbonyl-pentyl)-ureido]-pentanedioic acid di-tert-butyl ester. The compound was deprotected using the previously described methods and purified by HPLC to afford the desired product. 1 H NMR (tri-t-butyl ester of Z-protected amine) (400 MHz, CDCl 3 ,) δ 12.2 (s, 3H), 6.4 (s, 2H), 4.15 (m, 2H), 3.45 (m, 1H), 2.75 (bs, 1H), 2.2 (m, 4H), 1.90 (m, 2H), 1.65 (m, 2H), 1.50 (s, 2H), 1.35 (m, 2H). ESMS m/z: 622 (M−H) + .
(S)-2-(3,3-Bis-pyridin-2-ylmethyl-ureido)-pentanedioic acid (8) (MIP 1025)
The same experimental procedure as in the general synthesis, yielded 0.65 g, 48% of 2-(3,3-Bis-pyridin-2-ylmethyl-ureido)-pentanedioic acid di-tert-butyl ester. The compound was deprotected using the previously described methods and purified by HPLC to afford the desired product. 1 H NMR (400 MHz, DMSO-d 6 ) δ, 12.0 (bs, 2H), 8.68 (d, 2H), 8.00 (m, 2H), 7.41 (d, 4H), 7.14 (d, 1H), 4.73 (d, 4H), 3.96 (s, 1H), 2.18 (m, 2H), 1.80 (m, 2H).
(S,S)-2-{3-[3-(Bis-pyridin-2-ylmethyl-amino)-1-carboxy-propyl]-ureido}-pentanedioic Acid (9) (MIP 1028)
The same experimental procedure as in the general synthesis in scheme 1, yielded 0.16 g, 35% of 2-{3-[3-(Bis-pyridin-2-ylmethyl-amino)-1-carboxy-propyl]-ureido}-pentanedioic acid di-tert-butyl ester. The compound was deprotected using the previously described methods and purified by HPLC to afford the desired product. 1 H NMR (400 MHz, DMSO-d 6 ) δ 12.4 (br, 2H), 9.37 (s, 1H), 8.52 (d, 2H), 7.80 (t, 2H), 7.14 (dd, 4H), 6.45 (m, 2H), 4.49 (br, 4H), 4.12 (s, 1H), 4.05 (s, 1H), 3.21 (m, 2H), 2.24 (m, 2H), 1.80 (m, 2H), 1.40 (m, 2H).
ESMS m/z: (diethyl ester) 429 (M) + , 451 (M+Na).
(S,S)-2-{3-[5-(Bis-pyridin-2-ylmethyl-amino)-1-carboxy-pentyl]-ureido}-pentanedioic Acid (10) (MIP 1008)
The same experimental procedure as in the general synthesis, yielded 0.09 g, 12% of 2-{3-[5-(Bis-pyridin-2-ylmethyl-amino)-1-carboxy-pentyl]-ureido}-pentanedioic acid di-tert-butyl ester. The compound was deprotected using the previously described methods and purified by HPLC to afford the desired product. 1 H NMR (400 MHz, DMSO-d 6 ) δ 12.7 (s, 2H), 8.97 (s, 1H), 8.65 (dd, 2H), 7.91 (dd, 2H), 7.45 (m, 4H), 6.44 (d, 1H), 6.28 (d, 1H), 4.45 (br, 4H), 4.10 (m, 2H), 3.15 (br, 2H), 2.60 (m, 2H), 2.25 (m, 2H), 1.90 (m, 2H), 1.78 (m, 2H), 1.45 (m, 2H).
(S)-2-{3-[1-Carboxy-2-(4-iodo-phenyl)-ethyl]-ureido}-pentanedioic Acid (11) (MIP-1034)
The same experimental procedure as in the general synthesis, yielded 0.038 g, 5% of 2-{3-[1-Carboxy-2-(4-iodo-phenyl)-ethyl]-ureido}-pentanedioic acid di-tert-butyl ester. The compound was deprotected using the previously described methods. 1 H NMR (400 MHz, DMSO-d 6 ) δ 12.40 (s, 3H), 7.65 (dd, 2H), 7.05 (dd, 2H), 6.30 (m, 2H), 4.25 (s, 1H), 4.05 (s, 1H), 2.90 (m, 2H), 2.2 (m, 2H), 1.80 (m, 2H). ESMS m/z: 429 (M) + , 451 (M+Na).
(S,S)-2-{3-[1-Carboxy-5-(2-iodo-benzylamino)-pentyl]-ureido}-pentanedioic acid (12) (MIP 1035)
The same general procedure, using the previously prepared and protected 2-[3-(5-Amino-1-carboxy-pentyl)-ureido]-pentanedioic acid di t-butyl ester. The compound was deprotected using the previously described methods (5.5 mg, 66%). 1 H NMR (400 MHz, DMSO-d 6 ) δ 12.4 (s, 3H), 8.8 (s, 1H), 7.94 (m, 1H), 7.5 (m, 1H), 7.16 (t, 1H), 6.38 (m, 2H), 4.15 (m, 5H), 3.06 (s, 2H), 2.85 (s, 1H), 2.2 (m, 2H), 1.90 (m, 1H), 1.70 (m, 2H), 1.50 (s, 2H), 1.35 (m, 2H). ESMS m/z: 536 (M+H) + .
(S,S)-2-{3-[1-Carboxy-5-(3-iodo-benzylamino)-pentyl]-ureido}-pentanedioic (13) (MIP 1089)
The same general procedure, using previously prepared and protected 2-[3-(5-Amino-1-carboxy-pentyl)-ureido]-pentanedioic acid di-t-butyl ester. The compound was deprotected using the previously described methods (4.1 mg, 53%). 1 H NMR (400 MHz, DMSO-d 6 ) δ 12.4 (s, 3H), 8.7 (s, 2H), 7.9 (s, 1H), 7.8 (d, 1H), 7.44 (d, 1H), 7.22 (t, 1H), 6.25 (s, 2H), 4.09 (m, 5H), 2.89 (s, 1H), 2.75 (s, 1H), 2.2 (d, 2H), 1.90 (m, 2H), 1.65 (m, 2H), 1.40 (m, 2H).
(S,S)-2-{3-[1-Carboxy-5-(4-iodo-benzylamino)-pentyl]-ureido}-pentanedioic (14) (MIP 1072)
The same general procedure, using previously prepared and protected 2-[3-(5-Amino-1-carboxy-pentyl)-ureido]-pentanedioic acid di t-butyl ester. The compound was deprotected using the previously described methods (12 mg, 66%). 1 H NMR (400 MHz, DMSO-d 6 ) δ 12.4 (bs, 3H), 8.8 (br, 1H), 7.8 (d, 2H), 7.27 (d, 2H), 6.35 (br, 2H), 4.1 (m, 4H), 2.89 (m, 2H), 2.2 (d, 2H), 1.90 (m, 2H), 1.65 (m, 4H), 1.35 (m, 2H). ESMS m/z: 536 (M+H) + .
(S,S)-2-{3-[1-Carboxy-5-(4-fluoro-benzylamino)-pentyl]-ureido}-pentanedioic (15) (MIP 1090)
The same general procedure, using previously prepared and protected 2-[3-(5-Amino-1-carboxy-pentyl)-ureido]-pentanedioic acid di t-butyl ester. The compound was deprotected using the previously described methods. 1 H NMR (400 MHz, DMSO-d 6 ) δ 12.4 (br, 3H), 8.7 (br, 1H), 7.5 (m, 2H), 7.3 (m, 2H), 6.35 (m, 2H), 4.1 (m, 4H), 2.9 (m, 2H), 2.2 (d, 2H), 1.90 (m, 2H), 1.60 (m, 4H), 1.35 (m, 2H). ESMS m/z: 428 (M+H) + , 450 (M+Na).
(S,S)-2-{3-[1-Carboxy-5-(4-bromo-benzylamino)-pentyl]-ureido}-pentanedioic (16) (MIP 1094)
The same general procedure, using previously prepared and protected 2-[3-(5-Amino-1-carboxy-pentyl)-ureido]-pentanedioic acid di t-butyl ester. 1 HNMR (tri t-butyl ester) (400 MHz, CDCl 3 ) δ 7.52 (d, 2H), 7.32 (d, 2H), 6.28 (m, 2H), 3.98 (m, 2H), 2.55 (t, 2H), 2.48 (t, 2H), 2.22 (m, 2H), 1.85 (m, 2H), 1.62 (m, 2H), 1.45 (m, 2H), 1.37 (s, 27H), 1.28 (m, 2H) ESMS m/z: 642 (M+H) + . The compound was deprotected using the previously described methods. ESMS m/z: 474 (M+H) + .
(S,S)-2-{3-[1-Carboxy-5-(4-iodo-benzoylamino)-pentyl]-ureido}-pentanedioic acid (17) (MIP 1044)
The same general procedure, using previously prepared and protected 2-[3-(5-Amino-1-carboxy-pentyl)-ureido]-pentanedioic acid di t-butyl ester. The compound was deprotected using the previously described methods. 1 H NMR (400 MHz, DMSO-d 6 ) δ 12.4 (s, 3H), 8.45 (s, 1H), 7.8 (dd, 2H), 7.6 (dd, 2H), 6.3 (s, 2H), 5.75 (s, 1H), 4.1 (m, 4H), 3.2 (s, 2H), 2.25 (d, 2H), 1.90 (m, 1H), 1.65 (m, 2H), 1.4 (m, 2H).
2-{3-[1-carboxy-5-(4-iodo-benzenesulfonylamino)-pentyl]-ureido}-pentanedioic Acid (18). (MIP 1097)
In a round bottom flask 2-[3-(5-Amino-1-carboxy-pentyl)-ureido]-pentanedioic acid di t-butyl ester (300 mg, 0.62 mmol) is suspended in water (10 mL) and 1,4dioxane (10 mL) and TEA (1.75 mL, 1.25 mmol) was added followed by 4-iodo-benzenesulfonyl chloride and the mixture stirred overnight at 50° C. The reaction mixture was evaporated to dryness, taken up in DCM and chromatographed over silica gel to afford the desired product (375 mg, 80%) as a clear oil. The compound was deprotected using the previously described methods followed by HPLC purification to afford the desired product MIP-1097 as a whiter solid (270 grams, 90% yield). 1 H NMR (400 MHz, DMSO-d 6 ) δ 7.97 (d, 2H), 7.68 (t, 1H), 7.53 (d, 2H), 6.35 (dd, 2H), 4.10 (m, 1H), 4.00 (m, 1H), 2.65 (m, 2H), 2.22 (m, 2H), 1.9 (m, 1H), 1.7 (m, 1H), 1.55 (m, 1H), 1.45 (m, 1H), 1.35 (m, 2H), 1.25 (m, 2H), (3 CO 2 H not seen). ESMS m/z: 565 (M+H) + .
2-(3-{1-Carboxy-5-[3-(4-iodo-phenyl)-ureido]-pentyl}-ureido)-pentanedioic Acid (19) (MIP 1095)
In a round bottom flask 4-iodo-phenyl isocyanate (100 mg, 0.41 mmol) is dissolved in DCM (10 mL) containing TEA (0.057 mL, 0.4 mmol). 2-[3-(5-Amino-1-carboxy-pentyl)-ureido]-pentanedioic acid di t-butyl ester (200 mg, 0.41 mmol) was added and stirred for 3 hours. The reaction mixture was evaporated to dryness and the crude mixture taken up in methanol (5 mL). Dropwise addition to water (20 mL) afforded a white precipitate which was collected and washed with water (20 mL) and dried to afford the desired tri-tert butyl ester as a white solid which was deprotected directly using the previously described method to afford the desired product (158 mg, 53%) as a white solid. 1 H NMR (400 MHz, DMSO-d 6 ) δ 8.51 (s, 1H), 7.5 (d, 2H), 7.22 (d, 2H), 6.3 (t, 2H), 6.16 (t, 1H), 4.05 (m, 2H), 3.05 (m, 2H), 2.24 (m, 2H), 1.9 (m, 1H), 1.68 (m, 2H), 1.52 (m, 1H), 1.38 (m, 2H), 1.28 (m, 2H), (3 CO 2 H not seen). ESMS m/z: 565 (M+H) + .
Synthesis of Glu-Urea-β-Phenyl Glycines
(±)-3-Amino-3-(3-iodo-phenyl)-propionic Acid (20)
Malonic acid (2.2 g, 21.5 mmol) and 3-iodobenzaldehyde (5 g, 21.5 mmol) were suspended in ethanol (50 mL) and ammonium acetate (1.66 g, 21.5 mmol) was added and the reaction heated to a reflux overnight. The reaction was cooled to room temperature filtered and washed with ethanol followed by ether and dried to afford the product (3.4 g, 11.6 mmol, 54%) as a white solid. 1 H NMR (400 MHz, DMSO-d 6 ) δ 7.80 (s, 1H), 7.64 (dd, J=7.8 Hz, 1H), 7.42 (dd, J=7.6 Hz, 1H), 7.16 (dd, J=7.8 Hz, 1H), 7.14 (dd, J=7.6 Hz, 1H), 4.21 (m, 1H), 2.36 (m, 2H).
(±)-3-Amino-3-(3-iodo-phenyl)-propionic Acid Methyl Ester (21)
To a suspension of (±)-3-Amino-3-(3-iodo-phenyl)-propionic acid (3.1 g, 10.6 mmol) in methanol was added thionyl chloride (0.95 mL, 12.7 mmol) and the reaction was stirred at room temperature overnight. Concentration followed by trituration with ether gives a white solid. The solid is filtered, washed with ether and dried to afford the desired product (3.5 g, 10 mmol, 95%) as a white solid. 1 H NMR (400 MHz, DMSO-d 6 ) δ 8.79 (br, 2H), 8.01 (s, 1H), 7.74 (d, J=8.1 Hz, 1H). 7.57 (d, J=7.8 Hz, 1H), 7.21 (dd, J=8.1, 7.8 Hz, 1H), 4.56 (br, 1H), 3.54 (s, 3H), 3.23-3.17 (m, 1H), 3.04-2.98 (m, 1H).
(S,R) and (S,S)-2-{3-[1-(3-Iodo-phenyl)-2-methoxycarbonyl-ethyl]-ureido}-pentanedioic acid di-tert-butyl ester (22)
2-[(Imidazole-1-carbonyl)-amino]-pentanedioic acid di-tert-butyl ester (370 mg, 1.05 mmol) was dissolved in DCE (10 mL) and coiled to 0° C. MeoTf (142 μL, 1.25 mmol) was added and the reaction was allowed to proceed for 20 min. (±)-3-Amino-3-(3-iodo-phenyl)-propionic acid methyl ester (356 mg, 1.045 mmol) was added and the reaction was allowed to warm to room temperature and then warmed to 55° C. and stirred overnight. The reaction was diluted with DCM (50 mL) and washed with water (30 mL), 5% aq. Citric acid (30 mL), sat. sodium bicarbonate (30 mL), water (30 mL) and brine (30 mL). The organic layer was dried over sodium sulfate and concentrated to afford the crude product. The product was purified by column chromatography to afford the desired product (303 mg, 0.51 mmol, 49%) as a white foam. 1 H NMR (400 MHz, CDCl 3 ) δ 7.66 (s, 1H), 7.57 (d, J=7.6 Hz, 1H), 7.29 (s, 1H), 7.07-7.02 (m, 1H), 5.74 (br, 1H), 5.17 (br, 2H), 4.30 (m, 1 μl), 3.63 (s, 1.5H), 3.62 (s 1.5H), 2.88-2.76 (m, 2H), 2.38-2.24 (m, 2H), 2.10-2.00 (m, 1H), 1.90-1.80 (m, 1H), 1.46 (s, 9H), 1.44 (s, 9H).
(S,R) and (S,S)-2-{3-[2-Carboxy-1-(3-iodo-phenyl)-ethyl]-ureido}-pentanedioic Acid (23)
To a solution of (±) 2 -{3-[1-(3-Iodo-phenyl)-2-methoxycarbonyl-ethyl]-ureido}-pentanedioic acid di-tert-butyl ester (289 mg, 0.49 mmol) was dissolved in methanol (3 mL) and 2M LiOH (0.5 mL) was added and the reaction stirred at room temperature overnight. The reaction was diluted with water (20 mL) and the organic layer was extracted with ethyl acetate (2×20 mL) then acidified with 1N HCl to pH ˜2. The aqueous layer was extracted with ethyl acetate (3×20 mL), dried over sodium sulfate and concentrated to afford the crude product (206 mg, 0.36 mmol, 73%) as a white solid. To the crude material was added DCM (2 mL) followed by TFA (2 mL) and the reaction was stirred at room temperature overnight. Concentration followed by recrystallization from ethyl acetate afforded the desired product (22 mg, 0.047 mmol, 10%) as a white solid. 1 H NMR (400 MHz, DMSO-d 6 ) δ 12.39 (br, 3H), 7.64 (br, 1H), 7.56 (m, 1H), 7.30 (bm, 1H), 7.10 (bm, 1H), 6.72 (bm, 1H), 6.34 (bm, 1H), 4.94 (br, 1H), 4.03 (bm, 1H), 2.64 (br, 2H), 2.20 (br, 2H), 1.86 (br, 1H), 1.71 (br, 1H). ESMS m/z: 463 (M−H) + .
(S,S)-2-{3-[1-Carboxy-5-(2-chloro-benzylamino)-pentyl]-ureido}-pentanedioic (7) (MIP-1137)
The same general procedure as shown in Scheme 1, using previously prepared and protected 2-[3-(5-Amino-1-carboxy-pentyl)-ureido]-pentanedioic acid di-t-butyl ester. The compound was deprotected using the previously described methods to yield the desired product (100 mg, 45%) as an off-white solid. 1 H NMR (400 MHz, DMSO-d 6 ) δ 9.0 (br, 3H), 7.63 (d, 1H), 7.2 (m, 2H), 7.15 (d, 1H), 6.30 (d, 2H), 4.1 (m, 4H), 2.9 (br, 2H), 2.2 (m, 2H), 1.90 (m, 2H), 1.60 (m, 4H), 1.35 (m, 2H). ESMS m/z: 444 (M+H) + .
(S,S)-2-{3-[1-Carboxy-5-(3-chloro-benzylamino)-pentyl]-ureido}-pentanedioic (8) (MIP 1131)
The same general procedure as shown in Scheme 1, using previously prepared and protected 2-[3-(5-Amino-1-carboxy-pentyl)-ureido]-pentanedioic acid di t-butyl ester. The compound was deprotected using the previously described methods to yield the desired product (200 mg, 90%) as an off-white solid. 1 H NMR (400 MHz, DMSO-d 6 ) δ 8.9 (br, 3H), 7.6 (s, H), 7.43 (m, 3H), 6.39 (br, 2H), 4.1 (m, 4H), 2.9 (br, 2H), 2.2 (m, 2H), 1.90 (m, 2H), 1.60 (m, 4H), 1.35 (m, 2H). ESMS m/z: 444 (M+H) + .
(S,S)-2-{3-[1-Carboxy-5-(4-chloro-benzylamino)-pentyl]-ureido}-pentanedioic (9) (MIP 1135)
The same general procedure as shown in Scheme 1, using previously prepared and protected 2-[3-(5-Amino-1-carboxy-pentyl)-ureido]-pentanedioic acid di t-butyl ester. The compound was deprotected using the previously described methods to yield the desired product as (10 mg, 66%) as an off-white solid. ESMS m/z: 444 (M+H) + .
(S)-2-(3-((R)-5-(benzylamino)-1-carboxypentyl)ureido)pentanedioic Acid (10). (MIP-1106)
The same general procedure as shown in Scheme 1, using previously prepared and protected 2-[3-(5-Amino-1-carboxy-pentyl)-ureido]-pentanedioic acid di t-butyl ester. The compound was deprotected using the previously described methods to yield the desired product (5 mg, 47%) as an off-white solid. ESMS m/z: 410 (M+H) + .
2-(3-{1-Carboxy-5-[3-(phenyl)-ureido]-pentyl}-ureido)-pentanedioic Acid (11) (MIP 1111)
In a round bottom flask phenyl isocyanate (100 mg, 0.84 mmol) was dissolved in DCM (10 mL) 2-[3-(5-Amino-1-carboxy-pentyl)-ureido]-pentanedioic acid di t-butyl ester (409 mg, 0.84 mmol) was added and stirred for 3 hours. The reaction mixture was evaporated to dryness and the crude mixture was purified via flash column chromatography 2:1 hexanes/ethyl acetate to afford the tert-butyl ester as a white solid which was deprotected using TFA/CH 2 Cl 2 affording the desired product. 1 H NMR (400 MHz, DMSO-d 6 ) δ 12.5 (s, 3H), 8.54 (s, 1H), 7.40 (dd, 2H), 7.26 (dd, 2H), 6.30 (t, 2H), 6.17 (t, 1H), 4.05 (m, 2H), 3.05 (m, 2H), 2.44 (m, 2H), 1.90 (m, 1H), 1.68 (m, 2H) 1.52 (m, 1H). 1.40 (m, 2H). 1.29 (m, 2H). ESMS m/z: 439 (M+H) + .
2-(3-{1-Carboxy-5-[3-(4-bromo-phenyl)-ureido]-pentyl}-ureido)-pentanedioic Acid (12) (MIP 1129)
In a round bottom flask 4-bromo-phenyl isocyanate (100 mg, 0.50 mmol) was dissolved in DCM (10 mL). 2-[3-(5-Amino-1-carboxy-pentyl)-ureido]-pentanedioic acid di t-butyl ester (246 mg, 0.50 mmol) was added and stirred for 3 hours. The reaction mixture was evaporated to dryness and the crude mixture was purified via flash column chromatography 2:1 hexanes/ethyl acetate to afford the tert-butyl ester as a white solid which was deprotected using TFA/CH 2 Cl 2 affording the desired product
1 H NMR (400 MHz, DMSO-d o ) δ 12.5 (s, 3H), 8.55 (s, 1H), 7.35 (d, 4H), 6.30 (t, 2H), 6.18 (t, 1H), 4.08 (m, 2H), 3.05 (m, 2H), 2.22 (m, 2H), 1.90 (m, 1H), 1.68 (m, 2H), 1.52 (m, 1H), 1.40 (m, 2H), 1.30 (m, 2H). ESMS m/z: 518 (M+H) + .
2-(3-{1-Carboxy-5-[3-(4-chloro-phenyl)-ureido]-pentyl}-ureido)-pentanedioic Acid (13) (MIP 1110)
In a round bottom flask 4-chloro-phenyl isocyanate (100 mg, 0.65 mmol) was dissolved in DCM (10 mL) 2-[3-(5-Amino-1-carboxy-pentyl)-ureido]-pentanedioic acid, di-t-butyl ester (318 mg, 0.65 mmol) was added and stirred for 3 hours. The reaction mixture was evaporated to dryness and the crude mixture was purified via flash column chromatography 2:1 hexanes/ethyl acetate to afford the tert-butyl ester as a white solid (470 mg, 96%) which was deprotected using TFA/CH 2 Cl 2 affording the desired product
1 H NMR (400 MHz, DMSO-d 6 ) δ 12.5 (s, 3H), 8.35 (s, 1H), 7.40 (dd, 2H), 7.19 (dd, 2H), 6.30 (t, 2H), 6.10 (t, 1H), 4.08 (m, 2H), 3.05 (m, 2H), 2.32 (m, 2H), 1.90 (m, 1H), 1.68 (m, 2H), 1.52 (m, 1H), 1.40 (m, 2H), 1.30 (m, 2H). ESMS m/z: 474 (M+H) + .
(S)-2-(3-((R)-1-carboxy-5-(□yridine□ne-1-ylmethylamino)pentyl)ureido)pentanedioic acid. (14) (MIP-1108)
The same general procedure as shown in Scheme A, using previously prepared and protected 2-[3-(5-Amino-1-carboxy-pentyl)-ureido]-pentanedioic acid di t-butyl ester. The compound was deprotected using the previously described methods to yield the desired product (51 mg, 70%) as an off-white solid. 1 H NMR (400 MHz, DMSO-d 6 ) δ 8.9 (br, 3H), 7.95 (m, 5H), 7.6 (m, 2H), 6.35 (br, 2H), 4.1 (m, 4H), 2.9 (br, 2H), 2.55 (m, 2H), 2.25 (m, 2H), 1.70 (m, 4H), 1.3 (m, 2H). ESMS m/z: 460 (M+H) + .
2-(3-{1-Carboxy-5-[3-(3-iodo-benzyl)-ureido]-pentyl}-ureido)-pentanedioic acid (15) (MIP-1101)
The same general procedure as shown in Scheme 2, using previously prepared and protected 2-[3-(5-Amino-1-carboxy-pentyl)-ureido]-pentanedioic acid di t-butyl ester. The compound was deprotected using the previously described methods to yield the desired product. ESMS m/z: 579 (M+H) + .
(19S,23S)-2-(4-iodobenzyl)-1-(4-iodophenyl)-13,21-dioxo-2,14,20,22-tetraazapentacosane-19,23,25-tricarboxylic Acid (16) (MIP-1130)
The same general procedure as shown in Scheme A, using previously prepared and protected 2-[3-(5-Amino-1-carboxy-pentyl)-ureido]-pentanedioic acid di t-butyl ester. The compound was deprotected using the previously described methods to yield the desired product (8.3 mg, 10%) as an off-white solid. 1 H NMR (400 MHz, DMSO-d 6 ) δ 7.8 (d), 7.3 (d), 6.3 (dd), 4.25 (br), 4.05 (m), 2.97 (m), 2.85 (br), 2.22 (m), 2.05 (m), 0.90 (m), 1.64 (m), 1.48 (m), 1.35 (m), 1.2 (m). ESMS m/z: 936 (M+H) + .
Rhenium General Experimental:
The rhenium complexes of the SAAC-inhibitors are conveniently isolated from the reactions of the readily available precursor [Net 4 ] 2 -[Re(CO) 3 Br 3 ] with the SAAC-inhibitor. Since the donor sets provided by the SAAC terminus are well documented as effective chelators for the {M(CO) 3 } +1 core and have been designed to adopt the required facial arrangement about the metal site, the preparations of the complexes were unexceptional.
The {Re(I)(CO) 3 } + system followed similar reaction chemistry to that of the Tc-99m tricarbonyl core. The use of [Net 4 ] 2 [ReBr 3 (CO) 3 ], as the starting material led to facile formation of the fac-{Re(CO) 3 (L) 3 } core. The [Net 4 ] 2 [ReBr 3 (CO) 3 ] was readily derived from the [ReBr(CO) 5 ]. The synthesis of the Re(I) complexes was accomplished by reacting [Net 4 ] 2 [ReBr 3 (CO) 3 ] with the appropriate TEC ligand in the ratio of 1:1.2 in 10 ml of methanol. The reaction was allowed to heat at 80° C. for 4 hours. After cooling all of the following reaction products were all purified using a small silica column with yields ranging from 10-30%.
Glu-urea-Lys-PEG2-ReDP:
[Re(CO) 3 {(17R,21S)-11,19-dioxo-1-(□yridine-2-yl)-2-(□yridine-2-ylmethyl)-5,8-dioxa-2,12,18,20-tetraazatricosaue-17,21,23-tricarboxylic Acid}][Br]. (17)
(MIP-1133). The PEG2 dipyridyl compound, (17R,21S)-11,19-dioxo-1-(□yridine-2-yl)-2-(□yridine-2-ylmethyl)-5,8-dioxa-2,12,18,20-tetraazatricosane-17,21,23-tricarboxylic acid was prepared employing the same general procedure as shown in Scheme 1, using previously prepared and protected 2-[3-(5-Amino-1-carboxy-pentyl)-ureido]-pentanedioic acid di t-butyl ester. The rhenium ester complex was prepared employing the same procedure as described in the general rhenium experimental. The compound was deprotected using the previously described methods to yield the desired product (2 mg, 20%) as an off-white solid. 1 H NMR (400 MHz, DMSO-d 6 ) δ 8.8 (d), 8.00 (dd), 7.55 (d), 7.42 (dd), 6.45 (s), 3.95 (m), 3.4-3.6 (m), 2.45 (m), 1.25 (m), 1.1(m), 0.8 (m). ESMS m/z: 931 (M+H) 4 .
Glu-urea-Lys-PEG4-ReDP:
[Re(CO) 3 {(23R,27S)-17,25-dioxo-1-(pyridin-2-yl)-2-(pyridin-2-ylmethyl)-5,8,11,14-tetraoxa-2,18,24,26-tetraazanonacosane-23,27,29-tricarboxylic Acid}][Br]. (18)
(KM11-200). The PEG4 dipyridyl compound (23R,27S)-17,25-dioxo-1-(pyridin-2-yl)-2-(pyridin-2-ylmethyl)-5,8,11,14-tetraoxa-2,18,24,26-tetraazanonacosane-23,27,29-tricarboxylic acid was prepared employing the same general procedure as shown in Scheme A, using previously prepared and protected 2-[3-(5-Amino-1-carboxy-pentyl)-ureido]-pentanedioic acid di t-butyl ester. The rhenium ester complex was prepared employing the same procedure as described in the general rhenium experimental. The compound was deprotected using the previously described methods to yield the desired product. (5.1 mg, 29.6%) as a white solid. ESMS m/z: 1019 (M+H) + .
Glu-urea-Lys-PEG8-ReDP:
[Re(CO) 3 {(35R,39S)-29,37-dioxo-1-(□yridine-2-yl)-2-(□yridine-2-ylmethyl)-5,8,11,14,17,20,23,26-octaoxa-2,30,36,38-tetraazahentetracontane-35,39,41-tricarboxylic acid}][Br]. (19) (MIP-1132)
The PEG8 dipyridyl compound, (35R,39S)-29,37-dioxo-1-(pyridin-2-yl)-2-(pyridin-2-ylmethyl)-5,8,11,14,17,20,23,26-octaoxa-2,30,36,38-tetraazahentetracontane-35,39,41-tricarboxylic acid was prepared employing the same general procedure as shown in Scheme A, using previously prepared and protected 2-[3-(5-Amino-1-carboxy-pentyl)-ureido]-pentanedioic acid di t-butyl ester. The rhenium ester complex was prepared employing the same procedure as described in the general rhenium experimental. The compound was deprotected using the previously described methods to yield the desired product (8.0 mg, 30.4%) as a white solid. ESMS m/z: 1195 (M+H) + .
Glu-urea-Lys-C11PAMA-Re:
[Re(CO) 3 {(19R,23S)-13,21-dioxo-2-(□yridine-2-ylmethyl)-2,14,20,22-tetraazapentacosane-1,19,23,25-tetracarboxylic Acid}] (20) (MIP-1109)
The C11-PAMA compound, (19R,23S)-13,21-dioxo-2-(□yridine-2-ylmethyl)-2,14,20,22-tetraazapentacosane-1,19,23,25-tetracarboxylic acid was prepared employing the same general procedure as shown in Scheme A, using previously prepared and protected 2-[3-(5-Amino-1-carboxy-pentyl)-ureido]-pentanedioic acid di t-butyl ester. The rhenium ester complex was prepared employing the same procedure as described in the general rhenium experimental. The compound was deprotected using the previously described methods to yield the desired product (3.0 mg, 75%) as an off-white solid. ESMS m/z: 922 (M+H) + .
Table 1 below is a summary of synthesized PSMA inhibitors investigated.
TABLE 1 Summary of in vitro cell binding data of the additional or retested Glu-Urea-Lys derivatives. Compound MIP # X Description IC 50 (nM) — — PMPA 10 1033 — Glu-urea-Lys 498 1137 2-Cl 2-Cl-benzyl 245 1131 3-Cl 3-Cl-benzyl 277 1135 4-Cl 4-Cl-benzyl 2 1106 H Des-halo benzyl 2960 1111 H Des-halo diurea 12 1129 4-Br 4-Br-diurea 2 1110 4-Cl 4-Cl-diurea 4 1108 — 2-naphyl 154 1101 3-I 3-I-diurea 10 1130 4-di-I C11 4-di-iodo 300 1133 — PEG2Re 227 KM11-200 — PEG4Re NA 1132 — PEG8Re 1747 1109 — C11PAMA-Re 696 1027 4-I 4-I-benzoyl 3* 1095 4-I 4-I-diurea 10*
β-amino Acid Analogs
β-amino acid analogs of MIP-1072, MIP-1095, MIP-1027 specifically but the extension to other analogs such as the technetium conjugates as well as other halogen analogs is very desirable. We have no new examples to support this claim at this time.
Synthesis of {Re(CO) 3 } +1 Core Model Complexes
The properties of the Group VII metals technetium and rhenium are very similar due to their periodic relationship. It was anticipated that the metals would demonstrate similar reaction chemistry, which is often the case for the tricarbonyl, nitrogen, and thiazole chemistry of these two metals. Likewise, due to their similar size that stabilizes the spin paired d 6 electron configuration of M(I), perrhenate and pertechnetate have very similar reaction behaviors. Synthesizing the rhenium-TECs allowed us a facile route to structurally characterize the products. The periodic relationship between Tc and Re indicates that Tc-99m radiopharmaceuticals can be designed by modeling analogous rhenium complexes.
Some of the new compounds were synthesized with macroscopic quantities of rhenium for characterization by conventional methods, including mass-spectrometry, 1 H and 13 C NMR spectrometry. Following purification, the synthesized rhenium complexes were run through a HPLC column for purification and identification of retention times to compare with Tc reaction products. The rhenium-TEC complexes were also crystallized.
The rhenium complexes of the SAAC-inhibitors are conveniently isolated from the reactions of the readily available precursors {Re(CO) 3 (H 2 O) 3 } +1 and [Net 4 ] 2 [Re(CO) 3 Br 3 ] with the SAAC-inhibitor. Since the donor sets provided by the SAAC terminus are well documented as effective chelators for the {M(CO) 3 } +1 core and have been designed to adopt the required facial arrangement about the metal site, the preparations of the complexes were unexceptional.
General Experimental
The {Re(I)(CO) 3 } + system followed similar reaction chemistry to that of the Tc-99m tricarbonyl core. The use of [Net 4 ] 2 [ReBr 3 (CO) 3 ], as the starting material led to facile formation of the fac-{Re(CO) 3 (L) 3 } core. The [Net 4 ] 2 [ReBr 3 (CO) 3 ] was readily derived from the [ReBr(CO) 5 ]. The synthesis of the Re(I) complexes was accomplished by reacting [Net 4 ] 2 [ReBr 3 (CO) 3 ] with the appropriate TEC ligand in the ratio of 1:1.2 in 10 ml of methanol. The reaction was allowed to heat at 80° C. for 4 hours. After cooling all of the following reaction products were all purified using a small silica column with yields ranging from 10-30%.
[Re(CO) 3 (2-{3-[3-(Bis-pyridin-2-ylmethyl-amino)-1-carboxy-propyl]-ureido}-pentanediethyl Ester)][Br] (24)
1 H NMR (400 MHz, DMSO-d 6 ) δ 8.65 (dd, 2H), 7.85 (dd, 2H), 7.7 (dd, 4H), 7.25 (dd, 2H), 6.42 (dd, 1H), 6.0 (dd, 1H), 4.5 (m, 2H), 4.16 (m, 2H), 3.80 (m, 4H), 2.45 (m, 2H), 2.0 (dd, 2H), 1.5 (m, 4H), 1.25 (m, 6H). ESMS m/z: 812-815.
[Re(CO) 3 (2-{3-[5-(Bis-pyridin-2-ylmethyl-amino)-1-carboxy-pentyl]-ureido}-pentanedioic Acid)][Br] (25)
(MIP 1029). 1 H NMR (400 MHz, DMSO-d 6 ) δ 12.6 (s, 2H), 8.91 (s, 1H), 8.63 (dd, 2H), 7.85 (dd, 2H), 7.75 (dd, 4H), 7.3 (dd, 2H), 6.44 (d, H), 6.28 (d, 1H), 4.45 (s, 2H), 4.10 (m, 2H), 3.15 (s, 1H), 2.60 (m, 2H), 2.25 (m, 2H), 1.90 (m, 1H), 1.78 (m, 2H), 1.45 (m, 2H). ESMS m/z: 770-774.
2-{3-[1-Carboxy-5-(carboxymethyl-pyridin-2-ylmethyl-amino)-pentyl]-ureido}-pentanedioic Acid (26)
The same general procedure, using the previously prepared and protected 2-[3-(5-Amino-1-carboxy-pentyl)-ureido]-pentanedioic acid di t-butyl ester. The compound was deprotected using the previously described methods (2.2 mg, 65%). 1 H NMR (400 MHz, DMSO-d 6 ) δ 8.65 (d, 1H), 7.91 (dd, 1H), 7.56 (d, 1H), 7.45 (dd, 1H), 6.31 (m, 2H), 4.34 (s, 2H), 4.08 (m, 4H), 3.10 (m, 2H), 2.24 (m, 2H), 1.95 (m, 1H), 1.68 (m, 4H), 1.5 (m, 1H), 1.22 (m, 2H). ESMS m/z: 469 (M+H) + . M+1 469.
[Re(CO) 3 (2-{3-[1-Carboxy-5-(carboxymethyl-pyridin-2-ylmethyl-amino)-pentyl]-ureido}-pentanedioic Acid)] (27)
1 H NMR (400 MHz, DMSO-d 6 ) δ 8.75 (d, 1H), 8.13 (dd, 1H), 7.69 (d, 1H), 7.57 (dd, 1H), 6.45 (m, 2H), 4.75 (m, 1H), 4.50 (m, 1H), 4.20 (m, 2H), 3.61 (m, 4H), 3.15 (m, 2H), 2.38 (m, 1H), 2.0 (m, 2H), 1.75 (m, 4H), 1.62 (m, 1H), 1.25 (m, 2H). ESMS m/z 779-782 (M+2Na) + .
Synthesis of Glu-Urea-Lys(N-benzyl-X) analogs (3).
The compounds of the general structure 3 were prepared in overall yields ranging from 20-40% using the general route depicted in Scheme A. The key synthetic intermediate (1) was reacted with the appropriate aldehyde at room temperature in for one hour to form the □yridi base intermediate. The □yridi base was not isolated but was reduced in situ with sodium triacetoxyborohydride. The t-butyl ester protecting groups were removed using 50% TFA in DCM for 1 hour at room temperature. Upon completion of the deprotection, the reactions were concentrated on a rotary evaporator and purified by HPLC or flash chromatography to afford the desired products (3) in 40-80% yield.
Synthesis of Glu-Urea-Ureido(Phenyl-X) analogs
The following compounds of the general structure 8 were prepared in overall yields ranging from 20-60% by the route depicted in Scheme B. The key synthetic intermediate (4) was reacted with the appropriate phenylisocyanate at room temperature to afford the desired protected intermediates (5) in good yields. The t-butyl ester protecting groups were removed in the presence of 50% TFA in DCM for 1 hour at room temperature. Upon completion, the reactions were concentrated on a rotary evaporator purified by HPLC or recrystallization to afford the desired products (6) in 40-90% yield.
Preparation and Characterization of the Radio-labeled Complexes Technetium-99m Labeling
Preparation of the 99m Tc-labeled complexes were achieved by addition of 100 μL of a solution containing [ 99m Tc(CO) 3 (H 2 O) 3 ] + to 500 μL of 10 −4 M solutions of the inhibitor-SAAC. The mixtures were heated at 70° C. for 30 min. The products were analyzed for their radiochemical purity by reverse-phase HPLC.
The stability of the radiolabeled compounds in solution and in serum were determined as a function of time and solution conditions. Specifically, after radiolabeling and isolation, the product was stored at room temperature for 6 h after which HPLC analysis was performed to check for degree of label retention, as well as potential product degradation. The reformation of TcO 4 − and the presence of the reduced material TcO 2 was analyzed.
To assist in predicting the in vivo stability, ligand challenges were performed. Specifically, the stabilities of the 99m Tc complexes were investigated by incubating the HPLC purified complexes in 5% mouse serum at room temperature and 37° C. The ability of competing ligands, such as cysteine and DTPA, to extract Tc-99m from the complexes was studied by incubating the purified complexes with solutions (PBS pH 7.2) containing competing ligands at final concentrations of 0.1M.
The results of the labeling competition studies demonstrated no degradation of the Tc-99m-complexes out to 6 hours in the serum or the competing ligands study. The results of the incubation at 37° C. after 6 hours are shown in FIG. 2 .
Iodinations of DCT
Preparation of the iodine-131 labeled compound N—[N—[(S)-1,3-dicarboxypropyl]carbamoyl]-S-3-iodo-L-tyrosine (I-131-DCIT) was achieved by addition of 100 ul of [I-131] NaI in 0.1N NaOH to a PBS (pH 7.2) solution containing DCT (1 mg/mL) in an Iodogen Tube™ (Fisher Scientific, Pierce). The mixture was vortexed for 3 minutes and stored at room temperature for 20 minutes.
The stability of the radiolabeled compound in solution was determined as a function of time. Specifically, after radiolabeling and isolation, the product was stored at room temperature for 48 h after which HPLC analysis was performed to check for degree of label retention, as well as potential product degradation. The reformation of NaI and the presence of the reduced iodates was analyzed. The results of the labeling stability study demonstrated no significant degradation of the I-131 DCIT out to 2 days at room temperature. The results of the study are shown in FIG. 3 .
Preparation of the iodine-131 labeled compound 2-{3-[1-Carboxy-5-(4-iodo-benzoylamino)-pentyl]-ureido}-pentanedioic acid (I-131-MIP 1072) was achieved by addition of 100 ul of [I-131] NaI in 0.1N NaOH with 30 μl methanol with 0.5% acetic acid to a PBS (pH 7.2) solution containing MIP 1072 (1 mg/mL) in an IODOGEN TUBE (Fisher Scientific). The mixture was vortexed for 3 minutes and stored at room temperature for 20 minutes.
The stability of the radiolabeled compound in solution was determined as a function of time. Specifically, after radiolabeling and isolation, the product was stored at 37° C. for 3 days after which HPLC analysis was performed to check for degree of label retention, as well as potential product degradation. The reformation of NaI and the presence of the reduced iodates was analyzed. The results of the labeling stability study demonstrated no significant degradation of the I-131 1072 out to 3 days at room temperature in DMSO, 10% ethanol/saline, PBS pH 7.2, and 6% ascorbate/3% gentisic acid solution. The results of the study are shown in FIG. 4 .
Biological Characterization of SAAC-Urea-Glutamate Conjugates
The newly prepared SAAC-urea-Glu conjugates were screened in a human prostate cancer cell binding assay using PSMA-positive, LnCap cells, and PSMA-negative, PC3 cells. Compounds demonstrating specific uptake or binding to PSMA-positive cells will be studied for tumor localization in vivo.
In vitro cold screening assays verses I-131 DCIT. LNCaP and PC3 human prostate cancer cells were obtained from American Type Culture Collection, Rockville, Md. LNCaP cells were maintained in RPMI-1640 medium supplemented with 10% fetal bovine serum (FBS). PC3 cells were grown in F12K medium supplemented with 10% FBS. Binding of the radiolabeled compound and competition with cold derivatives to LNCaP and PC-3 cells was performed according to the methods of Tang et al. (Tang, H.; Brown, M.; Ye, Y.; Huang, G.; Zhang, Y.; Wang, Y.; Zhai, H.; Chen, X.; Shen, T. Y.; Tenniswood, M., Prostate targeting ligands based on N-acetylated alpha-linked acidic dipeptidase, Biochem. Biophys. Res. Commun. 2003, 307, 8-14) with appropriate modifications. Cells were plated in 12-well plates at approximately 4×10 5 cells/well and incubated for 48 hours in a humidified incubator at 37° C./5% carbon dioxide prior to addition of compound. Each unique SAAC-urea-Glu conjugate was prepared and diluted in serum-free cell culture medium containing 0.5% bovine serum albumin (BSA) in combination with 3 nM I-131 DCIT (known inhibitor). Total binding was determined by incubating I-131 DCIT without test compound. Plates were incubated at room temperature for 1 hour. Cells were removed from the plates by gently pipeting and transferred to eppendorff tubes. Samples were microcentrifuged for 15 seconds at 10K×g. The medium was aspirated and the pellet was washed twice by dispersal in fresh assay medium followed by microcentrifugation. Cell binding of I-131 DCIT was determined by counting the cell pellet in an automated gamma counter. Nonspecific binding was determined as the counts associated with the cells after incubating with 2 uM nonradiolabeled compound or 2-phosphonomethyl-pentanedioic acid (PMPA). The control compounds are depicted below.
The two key compounds for the binding assays, are shown above: the I-DCIT (Kozikowski et al) and 2-Phosphonomethyl-pentanedioic acid (PMPA—right), a potent inhibitor with IC 50 =6 nM.
(ii) In vitro dose screening. I-131 DCIT bound specifically to LnCap cells and not PC3 cells as is evident by the counts displaceable by nonradiolabeled compound or PMPA in LnCap cells only ( FIG. 5 ). Binding constants were determined by incubating LnCap cells with various amounts of nonradiolabeled DCIT in the presence of a constant amount of I-131 DCIT and dividing by the specific activity of each solution to determine the number of fmoles compound bound ( FIG. 6 ). The Kd was determined to be 264 nM and Bmax was 254 fmoles. Compounds MIP-1008 and MIP-1033 which at 2 uM competed with I-131 DCIT for binding to LnCap cells, were retested at various doses to determine IC-50 values ( FIGS. 7 and 8 ). While MIP-1072, MIP-1095, and MIP-1097 displayed IC50 values <50 nm compounds MIP-1008 and MIP-1033 exhibited IC-50s of 98 nM and 497 nM, respectively. Compounds MIP-1025, MIP-1028, and MIP-1029 did not compete for binding (Table 1).
In order to confirm the results of the Scatchard analysis of FIG. 7 indicating MIP-1072 internalization into LNCaP cells, the rate of uptake of MIP-1072 in LNCaP cells was monitored. Each well was dosed with 100 nM MIP-1072 (2 uCi/well) at 4° C. and 37° C. Binding to PSMA reached equilibrium after 15 min as evidenced by the plateau in the curve at 4° C. The cells incubated at 37° C. continued to internalize MIP-1072 after equilibrium had been reached. This result, FIG. 10 , confirms the Scatchard and indicates that MIP-1072 is indeed internalized.
(iii) Microsome Assay Experimental
Pooled male rat liver microsomes (1 mg/mL, BD Biosciences), NADPH regenerating system (1.3 mM NADP, 3.3 mM glucose 6-phosphate and 0.4 U/mL glucose 6-phosphate dehydrogenase, BD Biosciences) and test compound (50 μM MIP-1072, 50 μM DCT, and 100 μM phenacetin) were added to 0.1M potassium phosphate buffer (pH 7.4) in order to monitor the catastrophic degradation of the test compounds. The mixture was incubated at 37° C. and at the indicated time (0, 15, 60 min) the reaction was stopped by the addition of an equal volume of ice cold methanol (500 μL). The resulting slurry was then centrifuged at 21,000×G for 10 min and the supernatant was collected and injected onto an Agilent LCMS model MSD SL using a 95:5 water:acetonitrile (with 0.1% formic acid) to 40:60 water:acetonitrile (with 0.1% formic acid) gradient and monitoring for the parent ion only in single ion mode. The results, shown in FIGS. 11A and 11B , are expressed as degradation of the parent ion with respect to the 0 min time point.
The stability of MIP-1072 was assessed using rat liver microsomes. MIP-1072 (50 μM) and Phenacetin (100 μM) were incubated with rat liver microsomes at 37° C. for the indicated time. Phenacetin was used as a control substance that is known to be metabolized. MIP-1072 was not degraded by the rat liver microsomes during the incubation period. However, phenacetin was degraded by 22% after a 60 min incubation.
The lead compound, MIP 1072, was I-131-labeled for tissue distribution studies in mice with both LNCaP (PSMA positive) and PC3 (PSMA negative) tumors implanted. The compound was radiolabeled by the route shown below.
The tissue biodistribution results, were consistent with the in-vitro data, and demonstrated significant uptake in the LNCaP (PSMA positive) tumors. The results also displayed a high degree of specificity with very little activity in the PC3 (PSMA negative) tumors. A graph depicting the mice distribution is shown below ( FIG. 12 ).
The biological assessment using N—[N—[(S)-1,3-dicarboxypropyl]carbamoyl]-S-3-iodo-L-tyrosine (I-131-DCIT) verses “cold” complexes proved to be a rapid first screen, followed by dose curves to determine accurate IC 50 values. The lead series of compounds that exhibited IC50 values <50 nM. In vivo data of the lead series demonstrated high affinity, with 3% ID/g accumulating in the LNCaP tumors, and high specificity with the LNCaP-to-PC3 ratio exceeding 15- to 1.
LNCaP Cell Lysis Protocol
2 confluent T75 Flasks
Wash cells off the plate by pipetting up and down with media.
Wash with 0.32 M sucrose, re-centrifuge
Re-suspend cell pellet in 1 mL 50 mM Tris-HCl, pH 7.4, 0.5% Triton X-100
Centrifuge at 14000 rpm for 1 min to precipitate nuclei
Remove supernatant and divide into 50 uL aliquots
Store at −80 C.
Protein Assay:
Bio-Rad Protein Standard II—1.44 mg/ml
Since using detergent in lysis step, make working reagent, A′ by adding 20 uL of reagent S to each 1 mL of reagent A that will be needed for the run. (If a precipitate forms, warm and vortex)
Prepare 5 protein dilutions—0, 0.2, 0.4, 0.8, 1.6 mg/mL
Also prepare 1/10, 1/100, and 1/1000 dilutions of the unknown
Combine 25 μL standard/unknown, 100 μL A′, 800 μL reagent B in duplicate. Mix After ˜15 min measure absorbance at 750 nM
NAALADase Assay:
Rxn Buffer: 50 mM Tris-HCl, pH 7.4, 20 mM CoCl2, 32 mM NaCl Make cold NAAG (100 mM stock) dilute 1/100 in Rxn Buffer for 1 mM Combine 600 uL buffer and LNCaP cell lysate (200 μg) Pre-incubate 37 C for 3 min Pre-incubate Rxn Buffer and LNCaP cell lysate for 3 min at 37 C
Add 6 μL of 1 mM NAAG (for 1 μM final cone) spiked with 1,000,000 CPM of 3 H-NAAG (100 μL of 1 mM NAAG+10 μL of 3H-NAAG (10/Xi)). For competition add PMPA.
Incubate for 30 min
At indicated time, stop reaction by removing 100 uL of the reaction-mix and adding an equal volume of ice cold 0.25 M KH 2 PO 4 , pH 4.3 to stop the r×n
Apply ½ of mixture to 250 mg AG 50W-X4 cation exchange column (200-400 mesh,
H + form, swell resin with DI H2O prior to use). Save the other ½ for counting.
Wash column with 500 μL 1:1 Rxn Buffer/0.25MKH 2 PO 4
Elute with 3M KCl (1.5 mL)
Count 100 uL of the load, elution and reaction (diluted 1:6) to minimize quenching NOTES:
Time=0 control values will be subtracted from experimental time points
Results expressed as pmol 3 H-glutamate formed/min/mg protein
Grant says inc only 10 min to ensure linearity, although Luthi-Carter, et al (J Pharm Exp Therap 1998 286(2)) says 2 hours still no effect on linearity and less than 20% of the substrate consumed
Therapeutic Treatments
Compounds of the present can be used to inhibit NAALADase for therapeutic treatments. Diseases that could be receptive to NAALADase treatment include painful and sensory diabetic neuropathy, neuronal damage and prostate cancer, schizophrenia, colorectal cancer, inflammation, amyotrophic lateral schlerosis, or diabetic neuropathy. The present compounds can also be used an analgesic. Guidance for the modeling of such therapeutic treatments can be found in Goodman & Gilman's The Pharmacological Basis of Therapeutics, McGraw Hill, 10 edition, 2001, Pharmaceutical Preformulation and Formulation: A Practical Guide from Candidate Drug Selection to Commercial Dosage Form, CRC, 2001 and Handbook of Pharmaceutical Excipients, AphA Publications, 5 edition, 2005.
Competitive Binding of Analogs ( FIG. 16 )
The ability of non-radioactive analogs to compete with 131 I-DCIT for binding to PSMA was tested in the PSMA positive human prostate cancer cell line, LNCaP cells. LNCaP cells (300,000 cells/well) were incubated for 1 hour with 3 nM [ 131 I]-DCIT in the presence of 1-10,000 nM MIP-1072 in RPMI-1640 medium supplemented with 0.5% bovine serum albumin, then washed and counted in a gamma counter. All documents cited in this specification including patent applications are incorporated by reference in their entirety.
Direct Binding and Internalization of MIP-1072
The direct binding of 123 I-MIP-1072 to prostate cancer cells was examined ( FIG. 17 ). LNCaP cells, or the PSMA negative cell line, PC3 cells, were incubated in RPMI-1640 medium supplemented with 0.5% bovine serum albumin for 1 hour with 3 nM 123 I-MIP-1072 alone, or in the presence of 10 μM unlabeled MIP-1072, or 10 μM 2-(phosphonomethyl)-pentanedioic acid (PMPA), a structurally unrelated NAALADase inhibitor. Cells were washed and counted in a gamma counter.
The affinity constant (IQ) of MIP-1072 was determined by saturation binding analysis ( FIG. 18 ). LNCaP cells were incubated for 1 hour with 30-100,000 pM 131 I-MIP-1072 in HBS (50 mM Hepes, pH 7.5, 0.9% sodium chloride) at either 4° C. or 37° C. in the absence or presence of 10 μM unlabeled MIP-1072 (to determine non-specific binding). Cells were then washed and the amount of radioactivity was measured on a gamma counter. Specific binding was calculated as the difference between total binding and nonspecific binding. The affinity constant (K d ) of the interaction of MIP-1072 with PSMA on LNCaP cells was determined by saturation binding analysis performed by titrating 123 I-MIP-1072 (3 pM-1,000 nM) in the presence and absence of an excess of non-radiolabeled MIP-1072 (10 μM). A K d of 4.8 nM, and Bmax of 1,490 fmoles/10 6 cells at 4° C. was determined by nonlinear regression analysis using Graph Pad Prism software ( FIG. 18 ). The K d was not significantly different at 37° C., 8.1 nM. The Bmax, however, was greater at 37° C. than at 4° C.; 1,490 vs. 4,400 fmol/10 6 cells, respectively, indicating internalization of MIP-1072. The results below are representative of two independent analyses.
The ability of MIP-1072 to internalize in LNCaP cells was confirmed by an acid wash assay ( FIG. 19 ). LNCaP cells were incubated in HBS with 100 nM 123 I-MIP-1072 for 0-2 hours at 4 and 37° C. At the indicated time the media was removed and the cells were incubated in mild acid buffer (50 mM glycine, 150 mM NaCl, pH 3.0) at 4° C. for 5 minutes. After the brief incubation the cells were centrifuged at 20,000×g for 5 minutes. The supernatant and cell pellet were counted in a gamma counter. In order to confirm the results of the saturation binding analysis indicating MIP-1072 internalization into LNCaP cells, we monitored the rate of uptake of MIP-1072 in LNCaP cells. Each well was dosed with 100 nM MIP-1072 (2 uCi/well) at 4° C. and 37° C. Binding to PSMA reached equilibrium after 15 min as evidenced by the plateau in the curve at 4° C. The cells incubated at 37° C. continued to internalize MIP-1072 after equilibrium had been reached. The results show a time dependent, acid insensitive increase in radioactivity associated with the pellet at 37° C. but not at 4° C., indicating that 123 I-MIP-1072 is internalized at 37° C. but not at 4° C. ( FIG. 19 ).
Tumor Uptake and Tissue Distribution of 123 I-MIP-1072
A quantitative analysis of the tissue distribution of 123 I-MIP-1072 was performed in separate groups of male NCr Nude −/− mice bearing PSMA positive LNCaP xenografts (approximately 100-200 mm 3 ) administered via the tail vein as a bolus injection (approximately 2 μCi/mouse) in a constant volume of 0.05 ml. The animals (n=5/time point) were euthanized by asphyxiation with carbon dioxide at 0.25, 1, 2, 4, 8, and 24 hours post injection. Tissues (blood, heart, lungs, liver, spleen, kidneys, adrenals, stomach, large and small intestines (with contents), testes, skeletal muscle, bone, brain, adipose, and tumor) were dissected, excised, weighed wet, transferred to plastic tubes and counted in an automated γ-counter (LKB Model 1282, Wallac Oy, Finland). To compare uptake of 123 I-MIP-1072 in LNCaP versus PC3 tumors, and to demonstrate that the compound was on mechanism via competition with 2-(phosphonomethyl)-pentanedioic acid (PMPA), some mice bearing either LNCaP or PC3 xenografts were pretreated with 50 mg/kg PMPA 5 minutes prior to injection with 123 I-MIP-1072 and selected tissues were harvested at 1 hour post injection. MIP-1072, uptake and exposure was greatest in the kidney and LNCaP xenograft which express high levels of PSMA. Peak uptake in the kidney was 158±46% ID/g at 2 hours and the LNCaP xenograft was 17±6% ID/g at 1 hours ( FIG. 20 ). Uptake in these target tissues was rapid, whereas the washout was slower in the LNCaP xenograft. 123 I-MIP-1072 was demonstrated to be on mechanism in vivo as evidenced by the localization to PSMA expressing LNCaP tumors but not PC3 tumors which do not express PSMA ( FIG. 21 ). In addition, both the tumor and kidneys were blocked by pretreating the mice with PMPA, a potent inhibitor of PSMA. | Compounds of Formula (Ia)
wherein R is a C 6 -C 12 substituted or unsubstituted aryl, a C 6 -C 12 substituted or unsubstituted heteroaryl, a C 1 -C 6 substituted or unsubstituted alkyl or —NR′R′,
Q is C(O), O, NR′, S, S(O) 2 , C(O) 2 (CH2)p Y is C(O), O, NR′, S, S(O) 2 , C(O) 2 (CH2)p Z is H or C 1 -C 4 alkyl, R′ is H, C(O), S(O) 2 , C(O) 2 , a C 6 -C 12 substituted or unsubstituted aryl, a C 6 -C 12 substituted or unsubstituted heteroaryl or a C 1 -C 6 substituted or unsubstituted alkyl, when substituted, aryl, heteroaryl and alkyl are substituted with halogen, C 6 -C 12 heteroaryl, —NR′R′ or COOZ, which have diagnostic and therapeutic properties, such as the treatment and management of prostate cancer and other diseases related to NAALADase inhibition. Radiolabels can be incorporated into the structure through a variety of prosthetic groups attached at the X amino acid side chain via a carbon or hetero atom linkage. | 2 |
FIELD OF THE INVENTION
The present invention relates to hydraulic pumps and more particularly to a cavity-mounted hydraulic pump in which the components are clamped together by the fluid output pressure of the pump so that no bolts or other fasteners are necessary to hold the components together in a fluid-tight manner.
BACKGROUND OF THE INVENTION
Conventional hydraulic pumps of the type that are fitted into a cavity in a valve block or cylinder head, for example, are typically constructed of a number of pump components which are clamped or otherwise fastened together by a plurality of bolts or other types of fasteners. In one application, such hydraulic pumps are mounted in a valve block and are used to supply hydraulic pressure selectively to one or a plurality of hydraulic cylinders or jacks. One of the problems associated with the conventional hydraulic pumps used for that purpose, as well as for other purposes, is the difficulty of reducing the size, cost and weight of the hydraulic pump below a certain minimum for the required hydraulic output pressure and volumetric flow output. Heretofore, the need to hold the pump components together with fasteners, such as bolts, to prevent leakage, for instance, has made it difficult to miniaturize this type of pump below a certain minimum size and weight.
It would be desirable, therefore, to provide a hydraulic pump that can be securely held together without the use of fasteners, such as bolts, so as to minimize the size, weight and cost of the pump, yet that would still be provided with the clamping force necessary to hold the pump components together in a leak-tight manner.
SUMMARY OF THE INVENTION
The present invention is directed to an improved, pressure-clamped hydraulic pump that is characterized by low cost, and a small size and weight for given parameters of pump output pressure and volumetric flow rate. The hydraulic pump of the invention is described as a gear-type pump, but it should be understood that the principles of the invention can be applied to other types of positive displacement pumps, such as pistontype, vane-type, rotor-type pumps or the like.
The hydraulic pump of the invention is designed to be threadably inserted into an internally threaded cavity, such as in a valve block or cylinder head. When the pump is threaded into the cavity and tightened, the pump components are clamped together between the bottom of the cavity and the threads. The pump outlet discharges into the cavity. Because of a differential area between the internal and external pump components that are exposed to the outlet pressure of the pump, the external force on the pump components owing to the outlet pressure exceeds the internal force on the pump components so that there is a net force of fluid pressure that clamps the pump components together. Thus, as the pump output pressure increases, the external clamping force on the pump increases making the pump more and more leak-tight.
With the foregoing and other objects, advantages and features of the invention that will become hereinafter apparent, the nature of the invention may be more clearly understood by reference to the following detailed description of the invention, the appended claims and to the several views illustrated in the attached drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the pressure clamped hydraulic pump of the present invention;
FIG. 2 is a cross-sectional view of the hydraulic pump of the present invention taken along line 2--2 of FIG. 1;
FIG. 3 is a transverse cross-sectional view of the hydraulic pump of the invention taken along line 3--3 of FIG. 2;
FIG. 4 is a fragmentary cross-sectional detail taken along line 4--4 of FIG. 3;
FIG. 5 is a fragmentary side elevation view, partly in cross-section, showing the hydraulic pump of the invention mounted in a valve block and connected to a drive motor; and
FIG. 6 is a schematic illustration of a system for using the hydraulic pump of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Reference will now be made in detail to the preferred embodiment of the invention illustrated in the accompanying drawings, wherein like parts are designated by like numerals throughout. FIGS. 1-4 illustrate an exemplary embodiment of the hydraulic pump of the invention which is designated generally by reference numeral 10.
Referring to FIGS. 1-2, the pump 10 comprises a housing 12 made up of three components, a top or front cover 14, a gear housing 16, and a bottom or rear cover 18. A drive shaft 20 is rotatably mounted in bores 22, 22' in the front and rear covers, respectively. An idler shaft 24 is similarly rotatably mounted in bores 26, 26' in the front and rear covers, respectively. Balls 28, 30, 32 located in conical recesses 34 in the ends of the bores 22, 26, 26' axially support the shafts 20, 24 in the housing 12 for rotation and absorb the thrust forces of the shafts in a low friction manner. Although the components of the pump are preferably made of metal materials, it is contemplated within the scope of the invention that some or all of the pump components can be made of polymeric or other synthetic materials.
In the described embodiment, the pump 10 is a gear pump comprising a primary or driven pump gear 36 keyed to drive shaft 20 by a key 38 (FIG. 3) and a secondary or idler pump gear 40 meshed with pump gear 36 and keyed to idler shaft 24 by a key 42 (FIG. 3). Drive shaft 20 is provided with an hexagonal drive connection 44 at the upper end thereof and shaft 20 extends through a seal 46 mounted in a cylindrical recess 48 in the front cover 14 of the housing 12.
The rear cover 18 is provided with an axial inlet port 50 which directs hydraulic fluid to the inlet side 52 (FIG. 3) of the primary and secondary gears 36, 40. As the gears 36, 40 rotate in the direction shown by the arrows in FIG. 3, hydraulic fluid is pumped from the inlet side 52 to the outlet side 54 of the gears and out a radial outlet port 56 in said rear cover 18 shown in FIG. 5 and in dashed lines in FIG. 3.
Front cover 14 is has an annular flange 58 at the top thereof for retaining an O-ring seal 60 and is provided with an external thread 62. Another O-ring seal 64 is mounted on a shoulder 66 of the rear cover 18. The purpose of the seals 60, 64 and thread 62 will be described hereinafter in connection with FIG. 2.
Referring to FIGS. 4 and 5, the front cover 14, gear housing 16 and rear cover 18 are located with respect to one another by means of dowel pins 68. The number and location of the dowel pins 68 is such that the components will fit together in only one orientation, and two or more pins may be used. Flats 70 are formed on the periphery of the gear housing 16 to aid in locating the positions of the dowel pins 68. It will be understood that locating means other than dowel pins may be used to register the three components of the housing 12. For example, mating protrusions and recesses may be formed in the confronting surfaces of the front and rear covers and gear housing to provide for proper registration of the housing components.
Most of the pressurized hydraulic fluid from the high pressure outlet side 54 of the pump 10 passes through the outlet port 56. Any fluid leakage from the outlet side 54 passes to the low pressure or inlet side 52 of the pump 10 which communicates with the seal 46 and bores 22, 22', 26, 26' via a channel 47 (FIG. 2).
Now referring to FIG. 5, the pump 10 is shown installed in a cylindrical cavity or bore 72 in a typical valve block 74. Cavity 72 is internally threaded to receive the threads 62 of the front cover 14. An inlet channel 76 in the valve block 74 communicates with the bottom of the cavity 72 and an outlet channel 78 in the valve block 74 communicates with a sidewall of the cavity. The pump 10 is installed in the cavity 72 by threading the threads 62 into the cavity until the O-ring seals 60 and 64 seal the cavity 72 and the inlet channel 76, respectively. O-ring 64 seals and separates the low pressure inlet channel 76 from the high pressure portion of the cavity 72 including the outlet channel 78.
Threading of the pump 10 into the cavity 72 compresses the O-ring seals 60 and 64 and holds the pump parts securely together. When the pump 10 is operated, the internal pressure in the pump increases which tends to separate the front cover, gear housing and rear cover from one another. In conventional pumps, such separation is typically prevented by clamping bolts which pass through the pump components from top to bottom. In the pump according to the invention, no clamping bolts are used. Rather, the high pressure hydraulic fluid which has been pumped through the pump outlet 56 into the cavity 72 envelopes the lower end of the pump 10 and applies an axial fluid pressure or force thereto which forces the rear cover 18 into a tighter sealing contact with the gear housing 16 and front cover 14.
The external axial area of the pump on which the pressurized fluid acts is equal to the cavity cross-sectional area less the cross-sectional area enclosed by the O-ring seal 64. The internal axial area on which the high pressure fluid acts is, at most, equal to the axial area of the gear teeth between the roots and tips of the gears. Thus, the internal axial area is substantially less than the external axial area with the result that the pump components are clamped together by the force of the pumped fluid acting on the external axial area of the rear cover 18. Such force, of course, increases as the pump output pressure increases. This clamping force makes it possible to eliminate any clamping bolts or clamping fasteners for the pump.
The pump 10 is driven by a suitable drive motor 80 which is mounted to the valve block 74. The drive motor 80 has a motor drive shaft 82 with an axial blind bore 84 having a hexagonal cross-section which mates with the hexagonal drive connection 44 at the end of shaft 20 of the pump 10. Motor 80 may be any suitable type of motor, such as electric, pneumatic, or other rotational drive force.
FIG. 6 illustrates in schematic form one of many possible applications for the hydraulic pump of the present invention. In this application, hydraulic fluid is supplied from an oil reservoir 86 to the valve block 74 via a line 88 where it is drawn into the inlet of pump 10 and pumped under pressure to a hydraulic cylinder 90 via a line 92. Fluid may be exhausted to the oil reservoir via lines 94, 96 and valve block 74 by conventional valving means which forms no part of the present invention.
From the foregoing, it will be appreciated by those skilled in the art that the present invention provides a unique, low cost and small size hydraulic pump useful in many applications.
Although certain presently preferred embodiments of the present invention have been specifically described herein, it will be apparent to those skilled in the art to which the invention pertains that variations and modifications of the various embodiments shown and described herein may be made without departing from the spirit and scope of the invention. Accordingly, it is intended that the invention be limited only to the extent required by the appended claims and the applicable rules of law. | A pump assembly comprises a hydraulic fluid pump having a housing assembled from a plurality of housing components that are pinned together rather than being clamped together by bolts. The pump is disposed in a cavity in a valve block so that the outlet fluid pressure from the pump is applied axially to the housing components to create a greater external axial force on the pump components than the internal axial force and thereby maintain the housing components in tight, sealing relation without the need for clamping bolts or other clamping means. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention is related to handovers in a communication system and particularly, but not exclusively, to mobile telephone station handovers in an IP-based telecommunications network.
2. Description of the Related Art
Prior art office-based communications systems usually operate conventional fixed-line telephone units linked via an internal switchboard or PBX (private branch exchange). Such fixed-line systems are able to provide relatively high voice quality. However, user mobility is severely impaired.
The advent of digital mobile technologies such as GSM (Global system for mobile communications) however, means that mobile systems can now provide at least the equivalent voice quality as fixed-line systems. Mobile systems also allow greater freedom of movement for the user within the office than do fixed-line systems.
WIO (Wireless Intranet Office) is a proprietary communications system developed by the applicants which introduces the concept of utilising mobile telephone units, such as conventional GSM mobile stations, in an office environment. The system makes use of a known concept called Internet Telephony or Voice-over-IP. (IP is internet protocol).
Voice-over-IP is a technology which allows audio, data and video information to be transmitted over existing IP-based Local or Wide Area Networks or the Internet. The technology thus provides for convergence and integration of three different media types over the same network.
Prior to the advent of Voice-over-IP, offices often operated three separate networks for the transmission of these media types. As indicated above, fixed-line telephone systems coupled to an in-house PBX provided for voice communication, an officebased LAN (local area network) or Intranet (i.e. a packet-switched internal network), comprising computer terminals linked via network cards and under the control of a server station, provided for the transmission of “conventional” computer data and video cameras linked to monitors via fixed line or remote transmission link provided for video communication.
Voice-over-IP effectively combines these three media types such that they can be transmitted simultaneously on the same packet-switched network or IP-router throughout the office environment and beyond the confines of the office.
In order to provide for such media convergence, Voice-over-IP often uses a specific ITU (International Telecommunication Union) standard protocol to control the media flow over the Intranet. One common standard protocol used in Voice-over-IP systems, and the one used in the WIO system, is termed H.323.
H.323 is an ITU standard for multimedia communications (voice, video and data) and allows multimedia streaming over conventional packet-switched networks. The protocol provides for call control, multimedia management and bandwidth management for both point-to-point (2 end-users) and multipoint (3 or more end-users) conferences. H.323 also supports standard video and audio codes (compression/decompression methods such as MPEG) and supports data sharing via the T.120 standard.
Furthermore, H.323 is network, platform and application independent allowing any H.323 compliant terminal to operate in conjunction with any other terminal.
The. H.323 standard defines the use of three further command and control protocols:
a) H.425 for call control;
b) Q.931 for call signalling; and
c) The RAS (Registrations, Admissions and Status) signalling function.
The H.425 control channel is responsible for control messages governing the operation of the H.323 terminal including capability exchanges, commands and indications. Q.931 is used to set up a connection between two terminals. RAS governs registration, admission and bandwidth functions between endpoints and gatekeepers which are discussed later.
For a H.323 based communication system, the standard defines four major components:
1. Terminal
2. Gateway
3. Gatekeeper
4. Multipoint Control Unit (MCU)
Terminals are the user end-points on the network, e.g. a telephone, mobile or fixed, or a fax unit or a computer terminal. All H.323 compliant terminals must support voice communications, but video and data support is optional.
Gateways connect H.323 networks to other networks or protocols. For an entirely internal communications network i.e. with no external call facility, gateways as such are not required. However, a circuit providing the internal function of a gateway would normally be present. References to a gateway in the present description refers to any circuit providing the necessary gateway functions for internal or external communication.
Gatekeepers are the control center of the Voice-over-IP network. It is under the control of a gatekeeper that most transactions (communication between two terminals) are established. Primary functions of the gatekeeper are address translation, bandwidth management and call control to limit the number of simultaneous H.323 connections and the total bandwidth used by those connections. An H.323 “zone” is defined as the collection of all terminals, gateways and multipoint-control units (MCU—defined below) which are managed by a single gatekeeper.
Multipoint Control Units (MCU) support communications between three or more terminals. The MCU comprises a multipoint controller (MC) which performs H.425 negotiations between all terminals to determine common audio and video processing capabilities, and a multipoint processor (MP) which routes audio, video and data streams between terminals.
The conventional Voice-over-IP system described herein above normally utilise standard fixed-line telephone systems which are subject to the disadvantages outlined above, namely the lack of mobility and the lack of user commands.
The WIO concept takes Voice-over-IP further in that it provides for the use of conventional mobile telephone units, such as GSM mobile stations, within the Voice-over-IP system. To provide for such mobile communications within an intra-office communication network, WIO combines known Voice-over-IP, as described above, with conventional GSM-based mobile systems.
Thus, intra-office calls are routed through the office intranet and extra-office calls are routed conventionally through the GSM network. Such a system provides most or all of the features supported by the mobile station and the network such as telephone directories, short messaging, multiparty services, data calls, call barring, call forwarding etc. WIO, therefore, provides for integrated voice, video and data communications by interfacing an H.323-based voice-over-IP network with a GSM mobile network.
The WIO system is a cellular network, similar to the conventional GSM network and is divided into H.323 Zones as described above.
One H.323 Zone may comprise a number of cells. Two or more H.323 zones may be contained within an administrative domain. The allocation of H.323 zones to an administrative domain is an issue primarily concerning billing and is therefore not relevant to this invention.
Given the cellular nature of the WIO system, a major issue to be solved is that of handovers (sometimes known as handoff) i.e. the hand-off of control of a mobile station from a first cell in the network to a second cell in the network. A similar consideration applies to mobile stations in the conventional GSM network.
In such conventional GSM systems, the need for a handover of a mobile station to a different cell of the network is based on measurements made by the mobile station of the strength of signals transmitted from several base transceiver stations.
If the level of a signal transmitted by a base transceiver station, located in a different cell from that of the mobile, reaches a certain threshold level in relation to that of the base transceiver station located in the mobile station's current cell, handover of the mobile station is required and a handover request is issued to the network controller (mobile switching center).
In a similar manner, a mobile station operating in the WIO system is able to determine its position within the WIO network by comparing the signal strengths of the signals received by several base stations, in different cells, in the network.
However, added complexities arise for handovers in the WIO system since a mobile unit operating therein is not only able to move between cells within the WIO system, but also between zones and even between the WIO system itself and an external GSM network.
It can be seen, therefore, that there are several different types of handovers which may need to be executed in the normal operation of a WIO system. These types of handovers are:
a) The handover of a mobile from one WIO cell to another whilst in communication with another mobile.
b) The handover of a mobile from one WIO zone to another whilst in communication with another mobile.
c) The handover of a mobile from a cell within the WIO system to a cell within an external GSM system while in communication with another mobile and vice versa.
Handovers according to the types listed above are also subject to the conditions under which any ongoing call is made, such as the instantaneous location of each mobile station and the location of each mobile station when the call was set up.
During the handover of a mobile station from a first cell to a second cell, it is quite possible that a certain amount of data will be lost since the communications links from the second cell may not be fully set up when the communications links from the first cell are disconnected. It is preferable, therefore, to provide a handover procedure wherein the communications links from the first cell are not disconnected until the communications links from the second cell are fully set up.
SUMMARY OF THE INVENTION
According to one aspect of the present invention there is provided a method of effecting handover in a cellular communications network of a first mobile station between a source gateway and a target gateway, the first mobile station being engaged in a call with a second mobile station using a destination gateway wherein the source gateway, the target gateway and the destination gateway are connected by a switched packet communication path for conveying call data packets, the method comprising: i) opening a target port at the destination gateway for communication with the target gateway; ii) routing call data packets from the first mobile station via the target gateway to the target port on the switched packet communication path; iii) detecting receipt of said call data packets at the target port; and then, responsive to such detection, iv) routing call data packets from the second mobile station via the destination gateway to the target gateway on the switched packet communication path.
Another aspect of the invention provides a cellular communications network comprising: a plurality of gateways connected via a switched packet communication path for conveying call data packets between the gateways, each gateway being associated with circuitry for converting RF data from a mobile station to call data packets for transmission via the switched packet communication path, and each gateway having a set of selectable ports for transmitting and receiving call data packets on the switched packet communication path, the network further comprising: a central controller connected to the switched packet communication path and operative responsive to a handover required indication from a mobile station operating in the network to selectively open and close said ports to implement handover of the mobile station from one of said gateways to another of said gateways.
For a better understanding of the present invention, and to show how the same may be carried into effect, the present invention will now be described in more detail with reference to the accompanying drawings in which:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 a is a block diagram showing some of the components used in the implementation of a WIO system;
FIG. 1 b is a block diagram illustrating the communication pathways used during a call between an internal mobile station and an external mobile station;
FIG. 1 c is a block diagram illustrating the communication pathways used during a call between two internal mobile stations operating under the same gatekeeper;
FIG. 1 d is a block diagram illustrating the communication pathways used during a call between two internal mobile stations operating under different gatekeepers;
FIG. 2 is a block diagram illustrating the communication pathways between components of the WIO system before the mobile station handover;
FIGS. 3 and 4 are block diagrams illustrating the communication pathways between components of the WIO system during the mobile station handover; and
FIG. 5 is a block diagram illustrating the communication pathways between components of the WIO system after the mobile station handover.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the office environment, denoted by the dashed box 100 in FIG. 1, within which the WIO system is implemented, there is an IP (Internet Protocol) LAN 10 . The LAN 10 is operable to carry standard packet form data.
One or more mobile stations (MS) 1 communicate, i.e. transmit RF signals to and/or receive signals from, a base transceiver station (BTS) 2 . The base transceiver station 2 used in the WIO system is similar to base transceiver stations used in conventional GSM mobile communications systems in that it is connected to, and operates in conjunction with, a controller. In a conventional GSM system, the controller is termed a base station controller (BSC); in WIO, however, the controller is represented by a GSM radio access gateway 3 , the function of which will be described later.
The base transceiver station 2 receives RF signals transmitted by the mobile unit 1 and forwards them in a call format to the GSM radio access gateway 3 . The GSM radio access gateway 3 is also connected to the LAN 10 .
A WIO Gatekeeper (WGK) 4 is connected to the LAN 10 as is an H.323 terminal (H.323) 5 . The H.323 terminal 5 may be represented by a computer terminal which supports voice information.
Connected to the LAN 10 is a GSM gateway 8 . The GSM gateway 8 is also connected to a standard GSM network 40 as used in a conventional mobile communication system. The network is sometimes referred to as a public land network. The WIO system allows for the use of mobile telephone in the office environment to make both internal and external office calls. The functions of each of the components of FIG. 1 will now be described in more detail.
The GSM radio access gateway 3 performs similar functions to that of a base station controller in a conventional GSM network such as the management of radio resources and channel configuration and the handling of the base transceiver station configuration. However, the GSM radio access gateway 3 also provides conversion from GSM voice data to packet based data suitable for transmitting on the packet-based LAN 10 .
During a call, therefore, the GSM radio access gateway 3 converts the voice data in call format transmitted by the base station into packet-based call data suitable for transmitting on the LAN 10 .
The GSM radio access gateway 3 normally (but not always) controls a single base transceiver station. However, the GSM radio access gateway 3 is operable to convey more than one call through it simultaneously. To achieve this, it comprises a number of “ports”. Each port has a particular IP address. The IP addresses are always the same for one network interface and these ports are identified with port numbers. A particular port will receive only that data which is sent to its specific address. Thus if a particular component within the WIO system such as second GSM radio gateway wishes to communicate with it, the first GSM radio gateway has to open the required port and then the second GSM radio gateway must send its data to the address of that port.
The WIO Gatekeeper 4 is the main controller of the WIO system and has a high processing capability. Its function is to provide control services to the LAN 10 and the various user terminals. However, the WIO Gatekeeper 4 is also responsible for all of the functions which the H.323 protocol defines to its gatekeeper, including call management and call signalling. It is also responsible for mobility management. The WIO Gatekeeper 4 is able to manage the main different call types such as voice, data, facsimile and conference calls which can be established between a mobile station, a PC terminal and a normal telephone in any combination.
The GSM gateway 8 handles communication between the WIO environment and the GSM network via the mobile switching center (MSC). From the MSC viewpoint, the WIO appears to be a conventional base station system. The GSM gateway 8 also provides isolation means for disconnecting the WIO system from the MSC in the event of WIO system failure.
The telephone calls managed by the WIO system can be divided into internal calls and external calls. Internal calls are those calls where both mobile stations involved in the call are located within the WIO system, and external calls involve a mobile station which is not located within the WIO system.
The functions of the WIO system components described above will now be described, with reference to FIG. 1 b , in the context of a telephone call from a mobile station located within the WIO system (mobile A) to a mobile station located in an external network such as a GSM network (mobile B).
A first mobile station A transmits a radio frequency (RF) transmission signal TX, on a predetermined communication channel, to the base transceiver station 2 in a format conventional to GSM communications systems such as a time-slot format. The communication channel on which the mobile station A transmits the RF transmission signal TX is determined in a manner conventional to GSM communication systems.
A first base transceiver station 2 A receives the RF 40 transmission signal, down-converts it and then forwards it to the GSM radio access gateway 3 A controlling the BTS 2 A. In this respect, the base transceiver station 2 A and the GSM radio access gateway 3 A operate in a manner similar to a base transceiver station and a base station controller respectively in a conventional GSM network.
The GSM radio access gateway 3 A receives the down-converted transmission signal from the base transceiver station 2 and converts it from the conventional GSM time-slot format, to call data in a packet-based format which allows it to be transmitted along the LAN 10 to the GSM gateway 8 . Also, the GSM radio gateway 3 A composes a control signal CTRL which may include, for example, identification of the destination mobile unit, the IP address corresponding to that mobile unit and/or identification of the source mobile unit.
The control signal is then routed, in packet format, via the LAN 10 , to the gatekeeper 4 which, based on the information contained in the control signal CTRL, determines whether the destination mobile station B is located within the WIO system or external to the WIO system. If the mobile station B lies outside the WIO system, e.g. a conventional GSM mobile unit operating in the GSM network, the packet-based call signal CALL is routed along the LAN 10 to the GSM gateway 8 .
The GSM gateway 8 converts the call signal CALL from the packet-based format into a conventional GSM format such as a time-slot format. The converted call signal thus becomes the receive signal RX. The call signal CALL is also sent to destination identified in control signal CTRL (mobile station B).
The receive signal RX, in timeslot format, is forwarded from the GSM gateway 8 to a mobile switching center (MSC) 22 in the GSM network from where it is transmitted to the respective base station controller 24 and base transceiver station 26 , under which the mobile station B is operating, in a manner conventional to GSM.
Calls which are completely internal to the WIO system are handled slightly differently. Reference is made to FIG. 1 c.
The RF transmission signal TX, in timeslot format, transmitted by the first mobile station A is again sent to the base station 2 A which performs down conversion of the signal. The down-converted signal is forwarded to the GSM radio gateway 3 A which performs format conversion and generates control information as described above. From the GSM radio gateway 3 A, the control signal CTRL is sent to the Gatekeeper 4 via the LAN 10 . Paging is done only if the target/destination end system, that is mobile station has made a location update in the WIO system and the location information has not been used. The gatekeeper 4 thus, sends, via the LAN 10 , a paging broadcast message identifying the mobile station B to each GSM radio access gateway 3 in its zone.
If the second mobile station B is operating in the same H.323 Zone as the first mobile station A, i.e. under the same gatekeeper, the gatekeeper 4 will receive a paging response signal from a destination GSM radio gateway 3 B, i.e. the GSM radio gateway under which the mobile station B is operating, and the call is routed along the LAN 10 to that destination GSM radio gateway 3 B.
The destination GSM radio gateway 3 B converts the call signal CALL into a timeslot format. It is then sent, via its base transceiver station 2 B which performs up-conversion to RF, to the second mobile station B.
If the gatekeeper 4 determines that the second mobile station B is in a different H.323 zone to the first mobile station A even if the location information has not been used yet, the first gatekeeper 4 A (FIG. id) routes the control signal to a destination gatekeeper 4 B via the LAN 10 , i.e. the Gatekeeper under which the destination mobile station B is operating, which then also sends a paging broadcast message to each GSM radio access gateway in its zone. This gatekeeper under which the destination mobile station is operating may be determined via a directory information server or other location information database. If this can not be determined the target mobile station is not reachable. If the gatekeeper receives a paging response message from one of the GSM radio access gateways, the call signal is routed from the source GSM radio access gateway 3 A to the destination GSM radio access gateway (in this case denoted by reference numeral 3 B) via the LAN 10 and then out to the mobile station B, via its base transceiver station 2 B, in a manner similar to that described above.
FIGS. 2 to 6 show, respectively, the communication pathways before, during and after a handover. The following description illustrates the handover of a first mobile station A from a first cell of the WIO network to a second cell of the WIO network (denoted by mobile station A′) whilst in communication with a second mobile station B also located within the network.
In this context, the components of the first cell, i.e. the cell out of which mobile station A will move, are termed the source components while the components of the second cell, i.e. the cell into which mobile station A will move, are termed the target components. The components of the cell in which mobile station B is located are termed the destination components.
As shown in FIG. 2, before the handover, mobile station A communicates with mobile station B by transmitting an RF, timeslot-based signal to the source base transceiver station 2 A which down-converts the signal and sends it to the source GSM radio gateway 3 A. The source GSM radio gateway 3 A sends the control signal via the LAN 10 to the gatekeeper 4 . The gatekeeper 4 identifies the destination mobile station as the mobile station B and the packet-based signal is routed, via the LAN 10 , to a first port PORT 1 of the destination GSM radio gateway 3 B. The destination GSM radio gateway 3 B converts the signal back into GSM time slot format and forwards it to the destination base transceiver station 2 B which up-converts the signal to RF and transmits it to mobile station B.
When the source base station for the mobile station A determines, in a manner known per se and briefly described earlier, that a handover to another cell is required, the source base station sends a handover required indication message to the source GSM radio gateway 3 A. The source base station generates, based on the levels of the signals which the mobile station has measured from the surrounding base transceiver stations, a list of suitable target base transceiver stations to which the mobile station could be handed over (the candidate list) and forwards it, on a radio frequency control channel, to the source GSM radio gateway 3 A.
The source GSM radio gateway 3 A converts the message HO indicating that handover is required and candidate list signal into a packet-based signal suitable for transmitting on the LAN 10 and then sends it to the gatekeeper 4 via the LAN 10 . The gatekeeper 4 receives the message and the candidate list from the source GSM radio gateway 3 A (FIG. 2 ).
The gatekeeper 4 selects the first candidate target GSM radio gateway 21 on this candidate list and sends a handover request message HRM to it together with the address of the old or current port (port 1 ) for the incoming call stream of the destination GSM radio gateway 23 (FIG. 3 ).
If the target GSM radio gateway 3 a ′ is able to accept the handover, it responds to the request by opening a port PORT 2 for the incoming call stream from the destination GSM radio gateway (FIG. 4) and then sending an acknowledgement message ACK 1 , together with the address ADDR of the newly opened destination port PORT 2 , to the gatekeeper 4 via LAN 10 .
When the gatekeeper receives the acknowledgement message ACK 1 from the target GSM radio gateway 21 , it instructs the destination GSM radio access gateway to allocate a new port, PORT 3 , for receiving information from the target base station or GSM radio gateway. The gatekeeper also sends a handover command message HCM to the source GSM radio gateway instructing it to execute the handover. The source GSM radio gateway 3 converts this HCM message into a conventional GSM format signal such as a time-slot format signal and forwards it to the source base transceiver station.
The source base transceiver station then transmits this handover command message to the mobile station A and handover is executed. As shown in FIG. 5, the mobile station A (now represented by A′) stops transmitting to the source base transceiver station 2 A and begins transmitting to the target base transceiver station 2 A′.
When the target GSM radio gateway 21 receives the first call data packets from the mobile station A, it sends a handover detected message HDM to the gatekeeper 4 .
The call transmitted by the mobile station A is thus routed to the mobile station B via the target GSM radio gateway 3 A′ to the new port PORT 3 of the destination GSM radio gateway 3 B. When the destination GSM radio gateway 3 B receives a data packet from the target GSM radio gateway 21 , it begins to send its data packets to the new port PORT 2 in the target GSM radio gateway 3 A′.
When the target GSM radio gateway 21 and the mobile station A′ have completed the handover, it sends a handover complete message to the gatekeeper which then begins to disconnect all of the original communications links between the source GSM radio gateway and the destination mobile cluster interface. The source GSM radio gateway 3 also closes its port and the destination GSM radio gateway 23 closes its original port PORT 1 .
After the handover, therefore, the mobile station A′ continues to communicate with destination mobile station B via the target base transceiver station 22 and the GSM radio gateway.
In summary, the destination GSM radio access gateway allocates a new port for the incoming media stream before handover is executed and the destination GSM radio access gateway is prepared to send the outgoing media stream from mobile B to a specified and allocated port in the target GSM radio access gateway. When handover occurs and the first packet from the target GSM radio access gateway is received, the destination GSM radio access gateway redirects outgoing packets to the target GSM radio access gateway and closes the old port for the incoming media stream. The gatekeeper then releases all connections to the source GSM radio access gateway.
It can be seen, therefore, that embodiments of this invention reduces the risk of data loss during the handover procedure since the original communications links between the source GSM radio gateway 3 and the destination GSM radio gateway 23 are not disconnected until communication has been positively established between the target GSM radio gateway 21 and the destination GSM radio gateway 23 .
It should be noted that this embodiment is not limited to handovers entirely within the WIO system. For example, such a procedure may be implemented in a handover of a mobile station from a cell of the WIO system to a cell of an external network. In this case, the target GSM radio gateway 21 would be represented by the GSM gateway. Also in this case, the setting up of the communications links to the appropriate cell in the external network may be controlled by the mobile switching center.
As has been described, the mobile station A communicates with the mobile station B by specified communication channels which comprise a call channel defined by RF specific parameters between the mobile stations A and B and their respective base transceiver stations and a logical or routing channel which determines the routing of packets via the LAN 10 . The establishment of logical channels can be effected by one of the following routes within the handover procedure described above.
The destination GSM radio access gateway may not allocate a new port for receiving data from the target radio access gateway. Rather the new target port in the target GSM radio access gateway is identified to the destination GSM radio access gateway.
According to one possibility, two distinct unidirectional logical channel connections are made, one from mobile station A to mobile station B, followed by one in the reverse direction from mobile station B to mobile station A. According to this approach, an existing logical channel exists from the is source GSM radio access gateway 3 A to the destination GSM radio access gateway 3 B. A replacement logical channel connection from the target GSM radio access gateway 3 A′ to the destination GSM radio access gateway 3 B is established and is indicated in the gatekeeper by a “replacement for” parameter. However, mobile station 2 does not replace the channels until user data traffic on the new channel is recognised. As soon as call data on the new channel has been recognised, the mobile station B closes the old channel and requests a new replacement channel for the reverse direction. The target gateway 3 A′ gives the configuration of the new replacement channel for the reverse direction after handover is executed.
It is also possible to use embodiments of the present invention in a context where the channels are bidirectional. The gatekeeper will need to send a second message to the destination GSM radio access gateway for confirmation on the change in the modified bidirectional channel. When the destination GSM radio access gateway receives this confirmation message, it is permitted to start sending the outgoing media stream to the new channel.
A bidirectional logical channel connection may be made in one step from mobile station A to mobile station B. In this case, when a logical channel configuration is provided in the forward direction (from MSA to MSB), the configuration of a logical channel in the reverse direction is also included. When the mobile station B responds to the mobile station A with an acknowledgement of the new open logical channel, the logical channel configuration in the reverse direction is granted. When the handover execution is effected, the mobile station B receives a confirmation signal indicating that the new logical channel shall be used.
Whilst embodiments of the present invention have been described in the context of a GSM system, embodiments of the present invention can be used with any other access method including close division multiple access or other spread spectrum techniques, time division multiple access, frequency division multiple access and hybrids of any one or more systems.
One of the parties to the call may be wired or stationary, in alternative embodiments of the present invention. | A method of effecting handover in a communications network of a first mobile station between a source and a target gateway is provided. The first mobile station engages in a call with a second mobile station using a destination gateway. The source gateway, the target gateway and the destination gateway are connected by a switched packet communication path for conveying call data packets. The method sends call data packets from the first mobile station to a source port at the destination gateway. The method opens a target port at the destination gateway for communication with the target gateway and routes call data packets from the first mobile station via the target gateway to the target port on the switched packet communication path. The method detects receipt of the call data packets at the target port and routes the call data packets from the second mobile station to the target gateway. | 7 |
FIELD OF THE INVENTION
The present invention relates to power contacts with mating components positioned in connectors and where both the power contacts and the connectors have leads or pins for soldering to printed circuit boards or back planes.
BACKGROUND OF THE INVENTION
Some high density and eurocard connectors of the type having signal contacts therein with outwardly extending pins which are soldered into plated-through holes in a printed circuit board also include prior art power contacts with outwardly extending pins which are soldered into plated-through holes in the board for electrical connection to power circuits thereon. Further, the prior art power contacts included a non-removable, mating pin or socket, extending through the housing of the connector for electrical engagement with a complementary power contact positioned in a mating connector. In the event the mating component of the power contact became damaged during mating of the connectors, it was necessary to desolder the entire connector along with the power contact in order to replace the power contact.
It is now proposed to provide a power contact having a removable mating component thereon so that a damaged component can be replaced without the need to desolder and remove the entire connector and power contact from the board.
SUMMARY OF THE INVENTION
According to the present invention, the power contact is provided having a base with a threaded bore opening out onto opposing surfaces and terminal pins for being soldered in holes in a printed circuit board for electrical engagement with power circuits thereon. Further, the power contact includes a mating component for being disposed in a connector mounted on the printed circuit board immediately next to the base. The mating component includes a mating end for electrical engagement with complementary mating ends on other power contacts or the like and a threaded portion on the other end for being threadedly received in one opening in the bore. A screwdriver receiving slot in the end face of the threaded portion permits removing and replacing the mating component from the base by a screwdriver inserted into the bore from the other opening.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a high density connector with a power contact of the present invention soldered to a printed circuit board;
FIG. 2 is an exploded perspective view of the power contact;
FIG. 3 is a cross-sectional view, taken on line 3--3 in FIG. 1, of the connector and power contact mounted on the printed circuit board; and
FIG. 4 is a perspective view of the power contact mounted on the printed circuit board with the connector exploded therefrom.
DESCRIPTION OF THE INVENTION
As shown in FIG. 1, high density connector 10 includes a dielectric housing 12 with a plurality of cavities 14 opening onto front surface 16 and rear surface 18. A plurality of box receptacle contact elements (not shown) are positioned in cavities 14 with terminal pins extending out from rear surface 18 and down into plated-through holes 20 (FIG. 4) in printed circuit board 22 where they are soldered for electrical engagement with signal circuits (not shown) on board 22. Connector 10 further includes mounting ears 24 through which bolt 26 extends to mechanically secure connector 10 to board 22 by means of nut 28 (FIG. 4).
Power passages 30, singularly or in multiples, are provided in housing 12 to receive mating component 32 of power contacts 34. As shown in FIG. 3, passage 30 includes a smaller diameter portion 30A opening onto rear surface 18 of housing 12 and a larger diameter portion 30B opening onto front surface 16 of housing 12. Shoulder 30C within passage 30 faces towards front surface 16.
With reference to FIG. 2, power contact 34 includes the aforementioned mating component 32 and base 35.
Base 35 is a machined block with the preferred material being a copper alloy and finished with a gold flash or other suitable plating. Terminal pins 36, six being provided on the embodiment shown, extend outwardly from opposing edges of surface 38. Terminal pins 36 are adapted for insertion and soldering in plated through holes 40 (FIGS. 3, 4) in board 22 for electrical engagement with power circuits (not shown) thereon. Threaded bore 42 extends through base 35, opening onto opposing surfaces, 44, 46.
Mating component 32 includes stem 48, split collar 50 and socket 52.
Stem 48 is made from brass and finished with a gold flash. End section 54 thereon is threaded for threaded engagement with bore 42 in base 34 and includes slot 54A at the end face thereof. Opposing end section 56 includes a first cylindrical portion 56A, a smaller diameter, second cylindrical portion 56B and shoulder 56C therebetween and facing outwardly. Aperture 56D is provided in portion 56B, opening onto end face 56E. Center section 58, positioned between end sections 54, 56, is larger in diameter relative to the other structural elements of stem 48. Center section 58 provides shoulders 58A, 58B facing in opposite directions. Opposing flats 58C are provided on center section 58 for use in tightening component 32 onto base 34 by a wrench (not shown).
Split collar 50 is made from phosphor bronze and nickel plated. Outer surface 60 includes a short portion 60A which is parallel to inner surface 62, and a tapered portion 60B with the taper being away from portion 60A.
Cylindrical socket 52 is machined or drawn with the preferred material being beryllium copper and the finish being gold over nickel. Passage 64, having a funnel entrance 64A, opens out at front and rear faces 66, 68 respectively of socket 52. The outer surface 70 includes front portion 70A and rear portion 70B which converges inwardly from rear face 68 to front portion 70A. Slits 71 in socket 52, extending longitudinally from front face 66 towards rear face 68, define a plurality of spring fingers 72.
As shown in FIG. 3, wall 74 of socket 52 thickens inwardly adjacent rear face 68 to provide an interior slanting annular shoulder 76 which faces towards passage entrance 64A.
Socket 52 mates with a complementary pin (not shown) on a like power contact or otherwise. As is apparent to those skilled in the art, socket 52 could be replaced with some other mating means; e.g., the aforementioned pin, a tab terminal and so forth.
In assembling power contact 34, collar 50 is placed around first cylindrical portion 56A with the tapered portion 60B of outer surface 60 facing away from shoulder 58B of center section 58. Socket 52 is placed onto second cylindrical portion 56B with rear face 68 abutting shoulder 56C and secured thereon by upsetting end face 56E over onto interior shoulder 76 in passage 64 in socket 52 as shown in FIG. 3. Base 35 is added by threading end section 54 of stem 48 of component 32 into bore 42 until shoulder 58A on center section 58 abuts surface 44.
With reference to FIGS. 3 and 4, power contact 34 is added to connector 10 by inserting mating component 32 into passage 30 of housing 12 from rear surface 18. During insertion, split collar 50 compresses while passing through narrow passage portion 30A and recovers after passing shoulder 30C. With surface 44 on base 35 abutting rear surface 18 on connector housing 12 and collar 50 abutting shoulder 30C, power contact 34 is now locked into housing 12 but can be removed by inserting a collar compressing tool (not shown) up onto tapered portion 60B to compress collar 50 so that contact 34 can be withdrawn rearwardly. However, once connector 10 and power contact 34 are soldered onto circuit board 22, neither can be separated from the other by that method without desoldering.
With respect to power contact 34 of the present invention, in the event socket 52 becomes damaged, with a screwdriver, (not shown) engaging slot 54A from rear surface 46 of base 35, component 32 can be untreaded and withdrawn from front surface 16 of connector 10. A new component 32 can then be inserted into passage 30 from front surface 16 and threaded into base 35 again by use of the screwdriver.
Although slot 54A has been illustrated as preferred, other tool receiving means could be used; e.g. a hexagonal opening (not shown) for an Allen wrench.
As can be discerned, a power contact, for use with connectors mounted on printed circuit boards, having a mating component which can be replaced without desoldering the contact and connector from the board has been disclosed. The power contact includes a base having a threaded bore extending therethrough and terminal pins for being soldered in holes in the circuit board for electrical engagement with power circuits thereon. The power contact further includes a mating component for positioning in a passage in the connector and having a threaded end for removable engagement with the bore in the base and a socket at the other end for mating with a complementary power pin. A damaged component can be removed by being unthreaded by a screwdriver inserted into the bore at the back of the base and withdrawn from the front of the connector. A new component can be inserted into the connector from the front and threaded into the bore in the base in the same manner. | A power contact having a mating component removably mounted in a base. More particularly, the mating component includes a stem with a mating socket at one end and a threaded portion at another end which is threaded into one opening of a bore extending through the base. A screwdriver slot at the end face of the threaded portion is accessible through the other opening to the bore to remove and replace the mating component. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application, pursuant to 35 U.S.C. § 119(e), claims priority to U.S. Provisional Application Ser. No. 60/827,582, filed Sep. 29, 2006. That application is incorporated by reference in its entirety.
BACKGROUND
[0002] 1. Field of the Invention
[0003] The present disclosure relates generally to apparatuses for securing a shaker screen to a shaker. In particular, the present disclosure relates to wedging apparatuses and methods of forming wedging apparatuses.
[0004] 2. Background Art
[0005] Oilfield drilling fluid, often called “mud,” serves multiple purposes in the industry. Among its many functions, the drilling mud acts as a lubricant to cool rotary drill bits and facilitate faster cutting rates. Typically, the mud is mixed at the surface and pumped downhole at high pressure to the drill bit through a bore of the drillstring. Once the mud reaches the drill bit, it exits through various nozzles and ports where it lubricates and cools the drill bit. After exiting through the nozzles, the “spent” fluid returns to the surface through an annulus formed between the drillstring and the drilled wellbore.
[0006] Drilling mud provides a column of hydrostatic pressure, or head, to prevent “blow out” of the well being drilled. This hydrostatic pressure offsets formation pressures thereby preventing fluids from blowing out if pressurized deposits in the formation are breached. Two factors contributing to the hydrostatic pressure of the drilling mud column are the height (or depth) of the column (i.e., the vertical distance from the surface to the bottom of the wellbore) itself and the density (or its inverse, specific gravity) of the fluid used. Depending on the type and construction of the formation to be drilled, various weighting and lubrication agents are mixed into the drilling mud to obtain the right mixture. Typically, drilling mud weight is reported in “pounds,” short for pounds per gallon. Generally, increasing the amount of weighting agent solute dissolved in the mud base will create a heavier drilling mud. Drilling mud that is too light may not protect the formation from blow outs, and drilling mud that is too heavy may over invade the formation. Therefore, much time and consideration is spent to ensure the mud mixture is optimal. Because the mud evaluation and mixture process is time consuming and expensive, drillers and service companies prefer to reclaim the returned drilling mud and recycle it for continued use.
[0007] Another significant purpose of the drilling mud is to carry the cuttings away from the drill bit at the bottom of the borehole to the surface. As a drill bit pulverizes or scrapes the rock formation at the bottom of the borehole, small pieces of solid material are left behind. The drilling fluid exiting the nozzles at the bit acts to stir-up and carry the solid particles of rock and formation to the surface within the annulus between the drillstring and the borehole. Therefore, the fluid exiting the borehole from the annulus is a slurry of formation cuttings in drilling mud. Before the mud can be recycled and re-pumped down through nozzles of the drill bit, the cutting particulates must be removed.
[0008] One type of apparatus used to remove cuttings and other solid particulates from drilling mud is commonly referred to in the industry as a “shale shaker.” A shale shaker, also known as a vibratory separator, is a vibrating sieve-like table upon which returning used drilling mud is deposited and through which substantially cleaner drilling mud emerges. Typically, the shale shaker is an angled table with a generally perforated filter screen bottom. Returning drilling mud is deposited at the top of the shale shaker. As the drilling mud travels down the incline toward the lower end, the fluid falls through the perforations to a reservoir below thereby leaving the solid particulate material behind. The combination of the angle of inclination with the vibrating action of the shale shaker table enables the solid particles left behind to flow until they fall off the lower end of the shaker table.
[0009] The above described apparatus is illustrative of one type of shale shaker known to those of ordinary skill in the art. In alternate shale shakers, the top edge of the shaker may be relatively closer to the ground than the lower end. In such shale shakers, the angle of inclination may require the movement of particulates in a generally upward direction. In still other shale shakers, the table may not be angled, thus the vibrating action of the shaker alone may enable particle/fluid separation. Regardless, table inclination and/or design variations of existing shale shakers should not be considered a limitation of the present disclosure.
[0010] Preferably, the amount of vibration and the angle of inclination of the shale shaker table are adjustable to accommodate various drilling mud flow rates and particulate percentages in the drilling mud. After the fluid passes through the perforated bottom of the shale shaker, it may either return to service in the borehole immediately, be stored for measurement and evaluation, or pass through an additional piece of equipment (e.g., a drying shaker, a centrifuge, or a smaller sized shale shaker) to remove smaller cuttings and/or particulate matter.
[0011] Because shale shakers are typically in continuous use, repair operations, and associated downtimes, need to be minimized as much as possible. Often, the filter screens of shale shakers, through which the solids are separated from the drilling mud, wear out over time and subsequently require replacement. Therefore, shale shaker filter screens are typically constructed to be quickly removable and easily replaceable. Generally, through the loosening of several bolts, the filter screen may be lifted out of the shaker assembly and replaced within a matter of minutes. While there are numerous styles and sizes of filter screens, they generally follow similar design.
[0012] Typically, filter screens include a perforated plate base upon which a wire mesh, and/or other perforated filter overlay, is positioned. The perforated plate base generally provides structural support and allows the passage of fluids therethrough. While many perforated plate bases are flat or slightly arched, it should be understood that perforated plate bases having a plurality of corrugated or pyramid-shaped channels extending thereacross may be used instead. Pyramid-shaped channels may provide additional surface area for the fluid-solid separation process while guiding solids along their length toward the end of the shale shaker from where they are disposed.
[0013] In some shale shakers, a fine screen cloth is used with the vibrating screen. The screen may have two or more overlying layers of screen cloth and/or mesh. Layers of cloth or mesh may be bonded together and placed over a support, supports, or a perforated or apertured plate. The frame of the vibrating screen is resiliently suspended or mounted upon a support and is caused to vibrate by a vibrating mechanism (e.g., an unbalanced weight on a rotating shaft connected to the frame). Each screen may be vibrated by vibratory equipment to create a flow of trapped solids on top surfaces of the screen for removal and disposal of solids. The fineness or coarseness of the mesh of a screen may vary depending upon mud flow rate and the size of the solids to be removed.
[0014] FIG. 1 shows a conventional shaker apparatus that includes a lower frame 12 and an upper basket 14 . The shaker apparatus 10 may have a variety of shapes and configurations, but generally it is intended to receive solids-laden mud from a distribution box (not shown) into the basket 14 that is vibrated by a motor (not shown) relative to the frame 12 . The basket 14 includes an upstream end 18 , a downstream end 20 , a back wall 22 at the upstream end 18 , and two side walls 24 . The downstream end 20 is open. In operation, drilling mud including suspended solids is poured into the basket 14 over the back wall 22 and onto screen 16 . Once on the screen 16 , the solids-laden mud is vibrated toward the downstream end 20 , which causes the mud to pass through the screen 16 into a collection box (not shown), and out of the shaker apparatus 10 for further processing. The flow of the solids-laden mud is indicated at 25 in FIG. 1 . The solids continue to be conveyed downstream on the screen 16 toward the open end 26 where they are either dropped onto another screen for further separation or discarded.
[0015] Screen 16 may be mounted in the basket 14 with wedges 30 a that are hammered into place under wedge angles 32 that are welded to the inside of basket 14 at an angle corresponding to the angle of the wedge 30 a . In this manner, the screens 16 were installed by placing a pre-tensioned screen 16 onto support rails (not shown) in basket 14 . Once in place, a wedge 30 a is placed on top of the pre-tensioned screen 16 under wedge angle 32 and then hammered into engagement with the wedge angle 32 to apply a downward force on the screen 16 . Accordingly, contact between the screen 16 and the support rail (not shown) in basket 14 may be maintained.
[0016] Typically, wedges are formed by, for example, casting or compression molding. As known in the art, casting is a process by which a material is introduced into a mold while it is liquid, allowed to solidify in the shape of the mold, and then removed producing a fabricated part. Compression molding is a method in which molding material that is generally preheated is first placed in an open, heated mold cavity. The mold is closed with a top force or plug member, pressure is applied to force the material into contact with all mold areas, and heat and pressure are maintained until the molding material has cured. However, both of these manufacturing methods tend to be expensive.
[0017] Accordingly, there exists a need for a wedge for a shaker screen that is economically efficient in manufacturing and structurally robust to withstand the forces generated during installation.
SUMMARY OF INVENTION
[0018] In one aspect, embodiments disclosed herein relate to a wedging apparatus including an outer polygonal surface configured to secure a screen to a shaker, the outer polygonal surface having a bottom surface, a top surface opposite the bottom surface, and at least one end surface joining the top surface and the bottom surface, and an inner core defined by the outer polygonal surface, wherein the inner core defines a cavity.
[0019] In another aspect, embodiments disclosed herein relate a method of forming an apparatus for securing a screen to a shaker, the method including forming a mold of a wedging apparatus configured to secure a screen to a shaker, wherein a shape of the mold is an inverse of an outer polygonal surface having a bottom surface, a top surface opposite the bottom surface, and at least one end surface joining the top surface and the bottom surface, and an inner core defined by the outer polygonal surface, wherein the inner core defines a cavity, injecting a liquid resin into the mold, allowing the liquid resin to solidify, and removing the wedging apparatus from the mold.
[0020] Other aspects and advantages of the invention will be apparent from the following description and the appended claims.
BRIEF DESCRIPTION OF DRAWINGS
[0021] FIG. 1 is a perspective view of a conventional shaker screen system.
[0022] FIG. 2 is a side view of a shaker screen and wedging apparatus assembly in accordance with embodiments disclosed herein.
[0023] FIGS. 3A and 3B are perspective views of wedging apparatuses in accordance with embodiments disclosed herein.
[0024] FIG. 4A is a cross-sectional view of a wedging apparatus in accordance with embodiments disclosed herein. FIG. 4B is a perspective view of FIG. 4A in accordance with embodiments disclosed herein.
[0025] FIGS. 5A and 5B are cross-sectional views of wedging apparatuses in accordance with embodiments disclosed herein.
[0026] FIGS. 6A and 6B are cross-sectional views of wedging apparatuses in accordance with embodiments disclosed herein.
DETAILED DESCRIPTION
[0027] In one aspect, embodiments disclosed herein relate to shale shakers. More specifically, embodiments disclosed herein relate to wedging apparatuses for securing screens to a shale shaker. In another aspect, embodiments disclosed herein relate to methods of forming a wedging apparatus.
[0028] FIG. 2 shows an end view of a shaker screen assembly in accordance with embodiments disclosed herein. In this embodiment, a wall 50 of a shaker basket is illustrated including a wedge bracket 52 . A wedging apparatus 54 may be disposed between wedge bracket 52 and a shaker screen 56 . Wedging apparatus 54 may include any generally polygonal shaped structure capable of applying compressive force on shaker screen 56 and a shaker basket perimeter or support rail 58 . A sealing element 60 may be disposed between shaker screen 56 and support rail 58 to, for example, reduce leakage of drilling fluid and/or particulate matter therethrough.
[0029] FIG. 3A shows a wedging apparatus 300 in accordance with embodiments disclosed herein. As shown, wedging apparatus 300 includes an outer polygonal surface 302 that includes a top surface 304 , a bottom surface 306 , and two end surfaces 308 joining top surface 304 and bottom surface 306 . One of ordinary skill in the art will appreciate that wedging apparatus 300 may be any shape known in the art such that the wedging apparatus may wedge between two shaker components, thereby securing a screen. Referring briefly to FIG. 3B , in alternate embodiments, wedging apparatus 300 b may include only one end surface 308 , thereby forming a wedging apparatus 300 b of a substantially triangular shape.
[0030] Referring now to FIG. 4A , a cross sectional view of a wedging apparatus 400 in accordance with embodiments disclosed herein is shown. Similar to wedging apparatus 300 in FIG. 3A , wedging apparatus 400 includes an outer polygonal surface 402 that includes a top surface 404 , a bottom surface 406 , and two end surfaces 408 that join top surface 404 and bottom surface 406 .
[0031] Top surface 404 may be configured to slidably engage a wedge bracket (not shown) attached to an inside wall of a shaker basket (not shown). One of ordinary skill in the art will appreciate that the wedge bracket may be attached to the shaker basket at any angle to correspond with an angle of top surface 404 . Accordingly, top surface 404 may be formed at any angle α with respect to horizontal axis A, as known in the art. For example, in one embodiment, the angle α of top surface 404 may be 0 degrees, 5 degrees, 30 degrees, 45 degrees, or any angle as known to one of ordinary skill in the art. In an alternate embodiment, top surface 404 may be formed at an angle of 0 degrees while bottom surface 406 may be formed at any angle with respect to a horizontal axis.
[0032] As shown, outer polygonal surface 402 defines an inner core 410 . In one embodiment, as shown in FIG. 4B , inner core 410 may extend from a first side 414 though wedging apparatus 400 to a second side 416 , thereby forming a cored wedging apparatus 400 . Alternatively, first side 414 and second side 416 may substantially enclose inner core 410 , thereby forming a hollow wedging apparatus (not independently illustrated). Accordingly, FIG. 4A may represent a cross-sectional view of a hollow and substantially enclosed wedging apparatus 400 . Thus, inner core 410 defines a cavity (not independently illustrated). In some embodiments, the cavity may be filled, partially filled, traversed by ribs, or enclosed as described in greater detail below. In at least one embodiment, the cavity may be bisected to form two or more cavities.
[0033] Still referring to FIGS. 4A and 413 , outer polygonal surface 402 may be formed from any material known in the art. For example, outer polygonal surface 402 may be formed from a plastic, such as polyurethane, polypropolene, or nylon. In an alternate embodiment, the polygonal surface 402 may be formed from a composite material, such as glass-filled polypropolene. With reference to the embodiments shown in FIGS. 4A and 4B , inner core 410 may be filled with any material known in the art. For example, inner core 410 may be filled with a material that provides structural rigidity to wedging apparatus 400 . Alternatively, in one embodiment, inner core 410 may be filled with a plastic, such as, polyurethane, polypropolene, or nylon. In yet other embodiments, inner core 410 may be filled with a foam or gas.
[0034] FIG. 5A shows a cross sectional view of a wedging apparatus 500 in accordance with embodiments disclosed herein. Wedging apparatus 500 includes an outer polygonal surface 502 , including a top surface 504 , a bottom surface 506 , and two end surfaces 508 that join top surface 504 and bottom surface 506 , thereby defining an inner core 510 . A plurality of ribs 512 may be disposed within core 510 and may extend, for example, from top surface 504 , bottom surface 506 , or at least one end surface 508 to the bottom surface 506 , at least one end surface 508 , or top surface 504 . Accordingly, in one embodiment, the plurality of ribs 512 may form a plurality of truss-like structures. Alternatively, in another embodiment, as shown in FIG. 5B , a plurality of ribs 512 b may also extend between a first rib and a second rib or between a first rib and top surface 504 , bottom surface 506 , or end surface 508 . In one embodiment, wedging apparatus 500 may include a first side (not shown) and/or a second side (not shown), wherein the first side joins a first edge of top surface 504 and a first edge of bottom surface 506 , and the second side joins a second edge of top surface 504 and a second edge of bottom surface 506 . Accordingly, first and second sides may enclose inner core 510 .
[0035] In the embodiments shown in FIGS. 5A and 5B , plurality of ribs 512 , 512 b may be formed from any material known in the art. For example, plurality of ribs 512 , 512 b may be formed from a plastic, such as polyurethane, polypropolene, or nylon. In an alternate embodiment, plurality of ribs 512 , 512 b may be formed from a composite material, such as glass-filled polypropolene. Inner core 510 may be filled in and around the plurality of ribs 512 , 512 b with any material known in the art. In one embodiment, inner core 510 may be filled with a material that provides additional structural rigidity to the plurality of ribs 512 , 512 b and wedging apparatus 500 . For example, in one embodiment, inner core 510 may be filled with a foam or a gas.
[0036] In another embodiment, as shown in FIGS. 6A and 6B , a wedging apparatus 600 may include an outer polygonal surface 602 having a top surface 604 , a bottom surface 606 , two end surfaces 608 that join top surface 604 and bottom surface 606 , a first side 614 , and a second side 616 . Outer polygonal surface 602 defines an inner core 610 enclosed within top and bottom surfaces 604 , 606 , end surfaces 608 , and first and second sides 614 , 616 . A plurality of ribs 612 , 612 b may be formed in first and/or second sides 614 , 616 . The plurality of ribs 612 may extend from top surface 604 , bottom surface 606 , or at least one end surface 608 and extend to the bottom surface 606 , at least one end surface 608 , or top surface 604 . In another embodiment, the plurality of ribs 612 b may also extend between a first rib and a second rib or between a first rib and top surface 604 , bottom surface 606 , or end surface 608 .
[0037] In one embodiment, the plurality of ribs 612 , 612 b may extend a selected distance z from first side 614 into inner core 610 of wedging apparatus 600 . For example, the plurality of ribs 612 , 612 b may extend half the width w of wedging apparatus 600 . Alternatively, the plurality of ribs 612 , 612 b may extend along the entire width w of wedging apparatus 600 , that is, ribs 612 , 612 b extend from first side 614 through wedging apparatus 600 to second side 616 . In such an embodiment, distance z would be substantially the same a width w. One of ordinary skill in the art will appreciate that the ribs 612 , 612 b may extend any distance into wedging apparatus 600 such that the structural integrity of the wedging apparatus 600 is substantially maintained. In one embodiment, second side 616 may substantially enclose the wedging apparatus 600 , while first side 614 includes a plurality of ribs 612 , 612 b , as described above. Cavities formed between each rib may be filled with any material known in the art, for example, a foam or gas. When placed in a shaker, the first side 614 of wedging apparatus 600 may be positioned proximate a wall of the basket and the enclosed second side 616 of wedging apparatus 600 may be positioned to face the inside of the basket. Thus, mud flowing over the shaker screen may not come into contact with first side 614 , and therefore, inner core 610 . Because drilling fluid or mud will not contact the material in the inner core 610 , materials used to fill the cavities between the ribs of first side 614 may include materials with a lower chemical resistance.
[0038] In still other embodiments, a plurality of ribs 612 , 612 b may be formed on both the first and second sides 614 , 616 of wedging apparatus 600 and extend back a selected distance z (as shown, z denotes the selected distance from first side 614 , a selected distance is not independently illustrated for second side 616 ) into inner core 610 , such that the plurality of ribs 612 , 612 b extending back from first side 614 do not contact the plurality of ribs 612 , 612 b extending back from second side 616 . In one embodiment inner core 610 may include an additional cavity (not shown) formed between the two sets of ribs 612 , 612 b extending back from the first and second sides 614 , 616 . The cavity may be filled with any material known in the art, for example, a foam or gas. Alternatively, inner core 610 may be formed from a plastic as described below.
[0039] In the embodiments shown in FIGS. 6A and 6B , outer polygonal surface 602 , including both first and second sides 614 , 616 , may be formed from any material known in the art. For example, outer polygonal surface 602 may be formed from a plastic, such as polyurethane, polypropolene, or nylon. In an alternate embodiment, the polygonal surface 602 may be formed from a composite material, such as glass-filled polypropolene. In one embodiment, inner core 610 may be integrally formed with outer polygonal surface 602 . Accordingly inner core 610 may be formed from a plastic, such as polyurethane, polypropolene, or nylon, or a composite material, as described above. In an alternate embodiment, enclosed inner core 610 may be filled with a foam or gas.
[0040] In accordance with embodiments described above, a wedging apparatus may be formed by injection molding. In such an embodiment, a molten plastic is injected at a high pressure into a mold having an inverse shape of a desired wedging apparatus. The shape of the wedging apparatus may be, for example, any shape as detailed above and/or shown in FIGS. 3-6 . The mold may be formed by a toolmaker or moldmaker from metal, typically either steel or aluminum, and precision-machined to form smaller, more detailed features. Once the mold is filled with molten plastic, the molten plastic is allowed to cure and is then removed from the mold. As detailed above, the mold may be filled with any molten plastic known in the art, for example, polyurethane, polypropolene, or nylon. In alternate embodiments, the mold may be filled with a molten composite material, such as glass-filled polypropolene. One of ordinary skill in the art will appreciate that other materials may be used without departing from the scope of embodiments disclosed herein.
[0041] Alternatively, a wedging apparatus in accordance with embodiments described above may be formed by gas-assist injection molding. In this embodiment, molten plastic is injected into a mold, partially filling it with a predetermined amount of resin or molten plastic. A gas, for example, nitrogen, is introduced into the mold cavity. The gas forms hollow channels as it follows a path of least resistance, thereby directing the molten plastic to fill all areas of the mold. As the gas expands in the cavity, forcing the molten plastic outward, all of the surfaces receive substantially equal pressure. The molten plastic is allowed to cure, the gas may be vented through a nozzle or vent, and the wedging apparatus may be removed from the mold.
[0042] FIGS. 6A and 6B show an example of a wedging apparatus 600 in accordance with the embodiments disclosed herein that may be formed by injection molding. In such an embodiment, molten plastic may be injected at pressure into the mold, wherein the molten plastic is allowed to cure, and the solid plastic wedging apparatus 600 is removed from the mold. The wedging apparatus 600 , once removed, may be substantially solid with a plurality of ribs 612 , 612 b formed on the first and/or second sides 614 , 616 of the wedging apparatus 600 .
[0043] One of ordinary skill in the art will appreciate that any material known in the art may be used for both injection molding and gas-assist injection molding wedging apparatuses. In one embodiment, an outer polygonal surface of a wedging apparatus may be formed of any material with a low compression set and high impact performance. For example, an outer polygonal surface of a wedging apparatus may be formed of a plastic, such as polyurethane, polypropolene, or nylon, or a composite material, such as a glass-filled polypropolene. Further, an inner core of a wedging apparatus, defined by an outer polygonal surface, may be formed of or filled with any material known in the art. For example, an inner core of a wedging apparatus may be filled with a plastic, such as polyurethane, polypropolene, or nylon, or a composite material, such as a glass-filled polypropolene. Alternatively, an inner core of a wedging apparatus may be filled with a foam or gas. In embodiments where an inner core of a wedging apparatus is substantially enclosed, and therefore not in contact with drilling fluid flowing over a shaker screen, the inner core may be formed from or filled with a material of lower chemical resistance.
[0044] Advantageously, wedging apparatuses formed in accordance with embodiments disclosed herein may provide shortened cooling cycles, reduced surface warps, and increased structural stability. Advantageously, wedging apparatuses formed in accordance with embodiments disclosed herein may also be more cost efficient to manufacture. Moreover, wedging apparatuses formed in accordance with embodiments disclosed herein may be formed of more cost efficient materials, thereby providing more cost effective methods of forming wedging apparatuses.
[0045] Conventional wedges are often formed by open casting or compression molding. Injection molding a conventional wedge, having a basic wedge block structure, may result in warped edges due to the relative thickness of the wedge. Because the wedge is conventionally a solid piece of plastic, the molten plastic towards the middle of the wedge would cool much more slowly than the plastic towards the outer perimeter of the wedge, thereby causing the outer edges of the wedge to warp and deform out of shape. Advantageously, embodiments disclosed herein describe a wedging apparatus and a method of forming a wedging apparatus that may reduce the expenses of manufacturing and reduce the warp of the wedging apparatus during manufacturing, while maintaining the structural integrity of the wedging apparatus.
[0046] While the present disclosure has been described with respect to a limited number of embodiments, those skilled in the art, having benefit of this disclosure, will appreciate that other embodiments may be devised which do not depart from the scope of the present disclosure. Accordingly, the scope of the present disclosure should be limited only by the attached claims. | A wedging apparatus including an outer polygonal surface configured to secure a screen to a shaker, the outer polygonal surface having a bottom surface, a top surface opposite the bottom surface, and at least one end surface joining the top surface and the bottom surface, and an inner core defined by the outer polygonal surface, wherein the inner core defines a cavity is disclosed. A method of forming an apparatus for securing a screen to a shaker is disclosed, the method including forming a mold of a wedging apparatus configured to secure a screen to a shaker, wherein a shape of the mod is an inverse of an outer polygonal surface having a bottom surface, a top surface opposite the bottom surface, and at least one end surface joining the top surface and the bottom surface, and an inner core defined by the outer polygonal surface, wherein the inner core defines a cavity, injecting a liquid resin into the mold, allowing the liquid resin to solidify, and removing the wedging apparatus from the mold. | 1 |
CROSS-REFERENCE TO RELATED APPLICATION
The present invention discloses, inter alia, a storage carousel or rotating storage unit which is similar to that disclosed and claimed in a co-pending application Ser. No. 193,757 filed Oct. 3, 1980, and entitled "Carousel Automatic Storage and Retrieval System", which is a continuation of Ser. No. 910,453 filed on May 30, 1978, now abandoned. The present invention represents an improvement over the aforementioned co-pending application in the extraction/insertion mechanism disclosed therein.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a retrieval and storage mechanism used in conjunction with a carousel storage system for handling small parts and the like. More particularly, the present invention relates to an extraction and insertion platform which is an integral part of a rotating storage unit of the type which is computer controlled from a remote station.
2. Prior Art
In the above co-pending application, there is described a carousel automatic storage and retrieval system for inventory items such as those found in warehouses. These are numerous automatic storage and retrieval system used in warehouse applications. The prior storage and retrieval systems attempt, by various means, to reduce the time necessary to place inventory items in storage and the time required in retrieving those items from storage. Small parts cannot always be palletized and must often be stored in open bins or containers due to their size or delicate construction.
Conventional storage and retrieval systems utilize solid shelves whereby an extractor or picking mechanism must go to the shelf to pick the desired inventory item. The above co-pending application provides a system whereby the desired inventory items are brought to the extractor mechanism in baskets or bins as opposed to having solid shelves where the extractor mechanism must go to the shelf. Combining a single extractor mechanism with a plurality of independently operating systems which bring inventory items to the extractor can multiply the speed of operation.
However, the extractor mechanism of the above co-pending application employs vacuum pump suction rings mounted on the end of a traveling arm to insert containerized inventory items into storage or to extract containerized items from storage. The suction rings contact the sides of a container or tote bin in the carousel system, and are limited to a weight capacity of approximately 50 pounds. A tote bin in excess of fifty pounds would cause the suction cups to break loose from the traveling arm.
The side surfaces of the tote bins are required to have a special surface texture in order for the suction cups to operate properly. Additional problems due to contaminents on the surface of the tote bins, such as oil, can occur. The contaminents can cause a breakdown in either the integrity or the elasticity of the rubber suction cups.
In order to overcome these disadvantages of the prior art, the present invention is provided with a pair of driven arms which extend forward to catch the front lower lip of a tote bin or box and thereby extract the box onto a platform. The present invention has an increased weight capacity in excess of 350 pounds. The present invention is capable of operating properly regardless of the surface conditions of the tote bins.
SUMMARY OF THE INVENTION
In light of the above, the present invention provides an improved extractor and insertion mechanism or platform which is an integral part of a rotating storage system that is computer controlled from a remote station. The rotating storage unit is essentially identical to the storage carousels in the above co-pending application. The rotating storage unit is provided with a plurality of individual shelves which contain boxes or tote bins. The shelves are arranged vertically into columns which move along an oval track. The platform is driven vertically inside a permanently mounted elevator which is directly adjacent to the shelves. The platform is moved vertically to a selected position where it can extract or insert an item into a prescribed shelf in the rotational storage unit.
The extraction/insertion platform includes an extraction/insertion arm assembly which is slidably mounted on a portion of the platform. The arm assembly is moved by means of a motor driven traveler plate assembly which is affixed to a lower portion of the platform. The platform comprises a rectangular metal base and an attached mounting frame which fits inside the elevator. The interior of the platform includes a conveyor belt which passes over a pair of elongated belt mounting plates or brackets and a skatewheel assembly. The platform is also provided with a pair of pneumatic pop-up gates or retainer bars at the forward and rear ends of the platform along the sides of the conveyer belt. The gates hold a tote bin in place on the platform.
The arm assembly is provided with pneumatic cylinders located under each of the arms. A linkage in each arm raises the arm when its pneumatic cylinders is actuated. A traveler plate drive motor drives a sprocket which is located near the rear of the platform. A chain passes around this sprocket and around a similar sprocket located near the front end of the platform. A traveler plate drive assembly which comprises, in part, a cam follower is attached to the above chain. The cam follower is received in an elongated oval slot in a traveler plate. The traveler plate is an integral part of the arm assembly and is disposed below the conveyor belt and extends transversely with respect to the conveyor belt but parallel to the upper and lower flights thereof. The traveler plate is also provided with a pair of triangular flanges or plates mounted on its ends. The triangular flanges are received between two angle plates, which are affixed to the sides of the platform, to slide therebetween.
The arm assembly also comprises a pair of arms mounted on the traveler plate in longitudinal alignment with the conveyor belt. The elongated oval slot lies between the two arms in axial alignment with the traveler plate. The arms are each housed between two sides plates and are pivotally mounted thereto by means of a pivot pin which passes through suitable holes at the rear of the arms and side plates. The ends of the arms are provided with spring-loaded flippers or fingers which engage the bottom of a tote bin during the extraction operation.
The present invention is also provided with a solenoid-operated version of the arms and a solenoid-operated version of the pop-up gates.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an elevational view of an extraction/insertion platform being mounted on a supporting elevator adjacent to a rotating storage unit in accordance with the present invention;
FIG. 2 is an isometric view of the platform of the present invention with the extraction/insertion end being shown to the right;
FIG. 3 is a top plan view of the platform, with the extraction/insertion end being shown to the left;
FIG. 4 is a cross sectional view taken along section line 4--4 of FIG. 3, showing a portion of the platform the lower edge of which is actually horizontal in its operating position;
FIG. 5 is a cross sectional view taken along section line 5--5 of FIG. 3, showing a portion of a conveyor belt on the platform of the present invention;
FIG. 6 is a cross sectional view taken along section line 6--6 of FIG. 3, showing a solenoid operated pop-up gate which is located at the rear of the platform in accordance with the present invention;
FIG. 7 is a cross sectional view taken along section line 7--7 of FIG. 3;
FIG. 8 is a cross sectional view taken along section line 8--8 of FIG. 3, showing a solenoid operated pop-up gate which is located at the forward end of the platform in accordance with the present invention;
FIG. 9 is an enlarged isometric view of the forwardmost portion of the conveyor belt, with certain hidden parts being shown in dotted lines;
FIG. 10 is an enlarged isometric view of a pneumatically operated pop-up gate located at the rear end of the platform, with certain parts being cut-away to show hidden detail;
FIG. 11 is an enlarged isometric view of a pneumatically operated pop-up gate located at the front end of the platform, with certain parts being cut-away to show hidden detail;
FIG. 12 is an enlarged isometric view showing the details the plate drive of the arm assembly in accordance with the present invention;
FIG. 13 is an isometric view showing the arm assembly of the present invention with certain parts being cut-away to show hidden detail;
FIG. 14 is an enlarged isometric view of an arm linkage in accordance with the present invention;
FIG. 15 is a top plan view of the arm assembly;
FIG. 16 is a cross sectional view taken along section 16--16 of FIG. 15 showing a solenoid operated extraction/insertion arm; and
FIG. 17 is a cross sectional view taken along section line 17--17 of FIG. 8.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention relates to an improved extraction/insertion mechanism for use with a rotating storage unit. The rotating storage unit provides a means of automatic storage and retrieval for small parts and the like.
Referring to FIG. 1 an extraction/insertion platform 20 of the present invention is shown as an integral part of a storage system which also includes a rotating storage unit 21. Rotating storage unit 21 (including two vertical carousels) is essentially identical to the storage carousels in the above co-pending application. The rotating storage unit is provided with a plurality of individual shelves 22 which contain boxes or tote bins 26. Small parts, such as aircraft parts or computer parts, could be stored in the tote bins. The shelves 22 are arranged vertically into columns which move along an oval track 23. Each shelf 22 contains a tote bin 26 such that the plurality of tote bins 26 are arranged parallel to each other and are moved along the oval track 23 by means of a motor system (not shown) which is controlled from a remote digital keyboard operator's terminal (not shown).
As shown by the dotted lines, the platform 20 is moved vertically inside a permanently mounted supporting elevator 24, which is directly adjacent to a column of shelves 22. Two spaced vertical poles 25 (only one of which is shown) support the platform 20 and the platform is slidably attached thereto, such that platform 20 slopes downwardly toward the rotating storage unit 21. The platform is driven vertically, by means of an electric motor, a chain, and weights (none of which are shown), the latter being attached to the chain and being used as a counter balance; thus, the platform can be driven to a selected position where it can extract or insert an item (or bin) into a prescribed shelf in the rotating storage unit 21. The feeding or home position of the platform would be from a waist-high work station 28. The placement of the tote bins 26 is randomly done through the use of a remote laser scanner (not shown). The computer memory (not shown) in the operator's terminal remembers where each tote bin is stored in the system, and it will retrieve the desired coded bin upon command.
Referring to the drawings in detail, the extraction/insertion platform 20 of the present invention is shown in FIGS. 2 and 3. Platform 20 includes an extraction/insertion arm assembly 32, a conveyor belt assembly 34 and a skatewheel assembly 36, the greater details of which will be disclosed herein after. A traveler plate drive motor 38 is also shown, whose purpose will be disclosed hereinafter.
Referring in detail to FIGS. 2, 3, and 4, the platform 20 is comprised of a substantially rectangular base 40 and a mounting frame 42 which is disposed perpendicular to the base 40. The base comprises a front cover plate 44, a rear cover plate 46 and a pair of trapezoidal shaped side cover plates 48 and 50. The cover plates are joined together by a plurality of corner braces 52 in essentially rectangular relationship (see FIG. 3). Hereinafter the word "front" or "forward" represents an article or position on platform 20 which is adjacent to the rotating storage unit 21, and the word "rear" represents an article or position on the platform which is adjacent to work station 28. The mounting frame 42 provides a means to insert the platform 20 into the supporting elevator 24. Mounting frame 42 fits between the two vertical posts 25 and is slidably mounted therebetween. The mounting frame includes a lower cross channel 54, an upper cross channel 56 and two side channels 58 and 60. The lower cross channel 54 passes through an appropriate slot in the side coverplates 48 and 50 along the bottom portion of platform 20 and is affixed to the interior of the side cover plates 48 & 50, respectively, by means of a pair of cross channel braces 62. The side channels 58 and 60 are vertically disposed and are perpendicular to the platform 20, and are affixed thereto by means of bolts. The upper cross channel 56 is disposed above the platform in parallel relation to the lower cross channel 54, and is mounted on the two side channels 58 and 60 by means of a pair of upper channel braces 64. The upper channel braces are attached to the side channels and the upper cross channel by bolts.
Referring now to FIGS. 2, 3, 4, 5, and 9, the conveyor belt assembly 34 is longitudinally disposed in the center of platform 20, and is inclined downwardly toward the rotating storage unit 21. Conveyor belt assembly 34 comprises a conveyor belt 70, which slides over the top of a pair of slider bed angle plates 72 and 74. The slider bed angle plates 72 and 74 are mounted on a pair of front center braces 76 which are bolted to the front cover plate 44, and on a pair of rear center braces 78 which are bolted to the rear cover plate 46. The rear ends of slider bed angle plates are each provided with a drive support plate 80 and 82, respectively (see FIG. 10) which are affixed to the rear center braces 78. As best shown in FIG. 5, angle plates 72 and 74 are joined together by means of a bed plate 84 to form a channel. The bed plate 84 is bolted beneath the adjacent edges of the angle plates 72 and 74 as shown.
The belt 70 passes around a forward driven roller 90 and a rear drive roller 92. The forward driven roller is rotatably mounted on the forward ends of slider bed angle plates 72 and 74 by means of a shaft 94. The shaft 94 passes through suitable openings in the angle plates 72 and 74 and is held in place by a belt tension apparatus 96 (FIG. 9) which is received on each end of shaft 94.
The rear drive roller 92 is rotatably mounted on the rear ends of slider bed angle plates 72 and 74 by means of a shaft 100 which passes through suitable openings in the angle plates. The ends of shaft 100 are received in a pair of bearings 102 and 104 which are bolted to the angle plates 72 and 74, respectively, and to the drive support plates 80 and 82, respectively.
On the portion of the shaft 100 which extends outwardly beyond the bearing 102 is received a sprocket 108. A motor chain 110 passes around sprocket 108 and around another sprocket 112 which is rotatably mounted on a stub shaft (not shown). A belt drive motor 116 operates the belt 70 as follows: The belt drive motor 116 drives a gear reducer 118 which is affixed to a channel 120. The channel 120 is affixed to the platform 20 by means of a plurality of angle attachments 122. The output of the gear reducer drives the stub shaft on which the sprocket 112 is mounted. The belt assembly 34 is also provided with a pair of idler rollers 124 (FIG. 4) which are affixed to the slider bed angle plates 72 and 74.
The platform 20 is provided with a pair of longitudinally disposed skatewheel assemblies 36. The skatewheel assemblies 36 are disposed along the sides of the conveyor belt assembly 34. The skatewheel assembly comprises a plurality of modified skatewheels 130 which are rotatably mounted on a plurality of horizontally disposed rods 132. The rods 132 are received within a skatewheel angle attachment 134 which is affixed to a portion of the platform 20. Skatewheel assembly is also provided with a skatewheel guide 136 which is mounted on the outer portion of angle attachment 134.
Referring to FIGS. 13, 14, and 15 in detail, the arm assembly 32 comprises an elongated traveler plate 140 which extends transversely across the platform 20 and a pair of extraction/insertion arms 142 and 144. The traveler plate 140 is provided with a pair of triangular flanges or plates 146 mounted on its ends. Traveler plate 140 is also provided with an elongated oval slot 148, the purpose of which will be disclosed hereinafter.
The arms 142 and 144 are mounted on the upper portion of the transverse traveler plate 140 and extend longitudinally with respect thereto. The arms 142 and 144 are each housed between a pair of side plates 150 and 152, respectively. The arms 142 and 144 are pivotally mounted on side plates 150 and 152, respectively, by means of a pivot pin 154 which is received in suitable holes at the rear of the arms.
The arms 142 and 144 each comprise a pair of flippers 160 which are pivotally connected to the forward ends of the arms by means of a flipper pin 162. The flippers 160 are provided each with a flipper return spring 164 (the details of which are not shown) and spring pin 166. The spring 164 is coiled or wound around the pin 162 in a central recess 161 in the flipper 160. One end of the coil spring 164 is received in a spring slot 163 in the arm 142 (or 144) and the other end of the spring is disposed over the spring pin 166 to return the flipper 160 to the position shown in FIG. 13 after the flipper has been depressed. The arms 142 and 144 are also provided with a pusher block 168 mounted on top of each arm, for a purpose which will hereinafter appear.
Each arm is provided with a set of overtravel springs 170 which extend from the rear of each arm. The overtravel springs 170 are mounted on the arms 142 and 144 adjacent the pivot point generated by pivot pin 154 by means of a spring guide 172. Each spring guide 172 is received within a recess 173 provided in the rear ends of arms 142 and 144 such that the pivot pin 154 also passes through spring guide 172. Each arm 142 (or 144) is provided with a slot 175 (see FIG. 16) in which pin 154 is received for a purpose which will hereinafter appear.
The spring guide 172 is provided with a connecting rod 174 which extends rearwardly therefrom. The overtravel springs 170 comprise a pair of compression springs 176 which are each received on a guide rod 178. The guide rod 178 and connecting rod 174 are associated together by means of a spring plate 180 which is slidably received over the ends of the guide rods 178 and connected to the rod 174. The spring plate is locked in place by means of a lock nut 182 which is received on connecting rod 174. Now, if an excessive pushing force were exerted on the arm 144 towards the right (for example by a right hand force against the pusher block 168) the arm 144 could move to the right (in relation to FIG. 16) by virtue of slot 175 in which the pin 154 is received; at the same time, the right hand ends of the guide rods 178 would move outwardly through their holes in the spring plate 180 while the springs 176 would be compressed. When the pushing force was released from the arm 144, the springs 176 would return the elements to the position shown in FIG. 16.
The arms 142 and 144 are raised by means of pneumatic cylinders 184 (see FIG. 13) which are located, in parallel arangement, below the arms 142 and 144 and between the side plates 150 and 152, respectively. Each of the pneumatic cylinders 184 is connected to a cylinder block 186 which is affixed to the side plates. Each pneumatic cylinder is provided with a piston rod 188 which extends slidably beyond the block 186 and which is connected to a cylinder clevis 190, the latter being connected to an arm linkage 192 which raises each of the arms 142 and 144 when the cylinder is actuated. Each arm linkage comprises a bell crank 196 which is connected to the cylinder clevis 190, and a connecting link 198, the latter in turn being connected to an arm clevis 200. Each bell crank 196 is pivotaly connected to the side plate 150 or 152 by means of a pivot pin 202. The pivot pin is held in place by means of a roll pin 204. Each clevis 200 is bolted into the underneath side of the arms 142 or 144.
Returning to further consideration of FIGS. 2, 3 and 7, the arm assembly 34 is slidably mounted on a portion of the platform 20. As shown in FIG. 7, the triangular flanges 146 are slidably received between two side slider angles 210 which are affixed to the side covers 48 and 50 by means of bolts. The slider angles 210 are provided with a pair of strip slider plates 212 which are affixed to the angles 210 adjacent to the triangular flanges, and which provide a smooth surface for the flanges 146 to slide upon.
Referring to FIGS. 4, and 12, the arm assembly 32 is moved by means of a traveler plate drive assembly 220 which is driven by traveler plate drive motor 38. The arm assembly 32 is slidably mounted, in the manner described above, to a portion of the platform 20, such that the arms 142 and 144 are in longitudinal alignment with the platform between the skatewheel assemblies 36 and the conveyor belt assembly 34 (see FIG. 3).
The traveler plate assembly 220 comprises a sprocket 222 which is located near the rear (right in FIG. 4) of platform 20 and which is driven by motor 38 through suitable gearing and angle drive (not shown). A drive chain 224 passes around sprocket 222 and around a similar sprocket 226 which is located near the front of the platform. The sprocket 226 is rotatably mounted on a shaft 228 which is received within a bearing 230. The bearing 230 is bolted to a center channel 232 which is disposed beneath and parallel to the conveyor belt 70. The center channel 232 is affixed to the platform 20 by means of a pair of center channel braces 234 which are bolted to front center braces 76. The lower cross channel 54 is also lifted to center channel 232 by means of cross channel braces 62.
The traveler plate drive assembly 220 also comprises a cam follower 236 which is in the nature of a roller and which is received in the elongated oval slot 148 in the traveler plate 140. The cam follower 236 is attached to the drive chain 224 by means of a chain guide fixture 238 which is connected across the links of the chain as shown. More particularly, the cam follower is rotatably mounted on a pin 237 which is connected to and projects upwardly from the guide 238. The traveler plate drive motor is affixed to the center channel 232 by means of a tension angle 240. The motor 38 is provided with a chain reducer plate 242, which is bolted to one side of the tension angle 240, and tension block 244, which is received on a tensioning rod 246. The motor 38 is also provided with a plurality of reducers 248.
Referring to FIGS. 10 and 11, the platform 20 is also provided a rear "pop-up" gate assembly 250 and a forward "pop-up" gate assembly 252, respectively. The pop-up gates act as safety stops to prevent a tote bin 26 from falling off the platform 20. The rear pop-up gate assembly 250 comprises a rear crossmember or bar 254 and two upwardly extending rear retainer bars 256 which are adapted to extend through slots at the rear of slider bed angle plates 72 and 74 (in a manner to be disclosed hereinafter). The rear retainer bars 256 are slidably mounted on the angle plates 72 and 74 by means of bolts 258 which are received in slots 260. A pneumatic cylinder 262 is attached at its upper end to the cross member 254 and at its lower end to a swivel bracket 264. The swivel bracket 264 is bolted to a U-shaped bracket or hat section 266 which is affixed to the rear cover plate 46.
The forward pop-up gate 252 comprises a forward crossmember or bar 270 and two upwardly extending forward retainer bars 272 which are adapted to extend through slots at the forward ends of the slider bed angle plates 72 and 74 (in a manner to be disclosed hereinafter). The forward retainer bars 272 are slidably mounted on the angle plates 72 and 74 by means of bolts 274 which are received in slots 276. A pneumatic cylinder 277 is received in a square hole 278 cut in the center channel 232, and is attached at its upper end to a cylinder mount 280 which is bolted to center channel 232. The cylinder 277 is connected to the forward cross member 270 by means of its piston rod 282 which projects upwardly through the mount 280 and is bolted at its upper end to the crossmember.
The following summarizes the insertion operation of the present invention:
A computer control (not shown) directs the platform 20 to be raised to a prescribed empty shelf 22 of the rotating storage unit 21 (which has been rotated by the control of the computor). It will be assumed that a tote bin 26 is mounted on the platform 20 as shown in the dotted lines in FIG. 1. The conveyor belt motor is activated thus causing movement of the conveyor belt. The tot bin 26 rolls along the skatewheels 130 over the lowered arms 142 and 144 downwardly toward the now stationary storage unit. The belt 70 stops momentarily as a sensor (not shown) alerts the computer that the forward end of the tote bin 26 is approaching the forward retainer bars 272. The retainer bars are lowered, by powering up the pneumatic cylinder 276 which causes a reverse pressure, which allows the tote bin 26 to pass over the forward end of the platform 20. The belt motor 116 is reactivated, and tote bin 26 is moved or slid partially onto the shelf 22.
The pneumatic cylinders 184 are now actuated, which activates the linkage assemblies 192 to raise the arm 142 and 144 simultaneously. The traveler plate drive motor 38 is activated when the tote bin passes aforementioned sensor, (not shown) which is located just to the rear of the forward retainer bars 272, thus causing the arm assembly to move forwardly toward the unit 21. The traveler plate drive motor 38 drives the sprocket 222 which subsequently drives the chain 224 around sprocket 228. The cam follower 236 rides in the slot 148 in the traveler plate 140; such that, as the chain guide fixture 238 moves in an elongated oval path (with respect to platform 20), cam follower 236 moves from side to side in the oval slot 148.
As the arms 142 and 144 move forward toward the rotating storage unit 21, the pusher blocks 168 on top of each arm, 142 and 144 engage the lower end of the tote bin and effect the final movement of the tote bin 26 into the shelf 22, in that, the arms 142 and 144 push the tote bin across the gap left by the belt 70. The forward movement is aided by the conveyor belt 70. As the arms 142 and 144, approach full extension, the weight of the tote bin beings the transfer to the shelf 22. At full extension, the tote bin 26 is seated on the shelf by the arms 142 and 144. The overtravel springs 170 at the ends of the arms allow the cam follower to move laterally in the slot 148 in the traveler plate, while the chain guide travels around sprocket 226. As the cam follower reaches the center of slot 148, the forward movement of the traveler plate 140 stops and the overtravel springs reach their maximum compression.
Another sensor, such as a photo-electric eye (not shown) or the like, mounted on the side at the front of the platform causes a signal to be sent to the computer controls when the tote bin 26 is seated on a shelf 22. The pneumatic cylinders 184 in the arm 142 and 144 are deactivated, thus causing them to drop away from the tote bin. The arm assembly 32 begins to move rearwardly as the cam follower crosses the center of the oval slot 148. The motors 38 and 116 are turned off when the arm assembly reaches its rearwardmost point, which is at a point where the flippers 160 at the ends of the arms 142 and 144 are disposed directly above the lower cross channel 54.
The following summarizes the extraction operation of the present invention:
The platform is positioned by means of computer controls at the proper shelf level for extraction of a tote bin 26. The pneumatic cylinders 184 are activated thereby raising the arms 142 and 144. The two drive motors 38 and 116 are activatedl; first motor 38 to cause the arm assembly 32 to move forward toward the rotating storage unit; and then the other motor 116 to move the conveyor belt toward the rear of the platform 20. The traveler belt drive motor 38 does not reverse due to the aforementioned drive chain 224 and traveler plate 140 interaction; however, the coveyor belt motor 116 is reversed from its direction during the above insertion operation.
The forward retainer bars 272 are again lowered, as the arms 142 and 144 travel toward the rotating storage unit. The arms contact the tote bin on the shelf as they approach their full travel point. The flippers 160, at the ends of arms 142 and 144, rotate about the pivot point 162 to be lowered as they contact the bottom of a tote bin 26. A notch or slave palette (not shown) is provided in the tote bin to receive the flippers 160 approximately one inch past the initial contact point. The flippers are spring loaded such that, the flippers 160 rotate (or return) to their original position to present a surface which faces pusher block 168, thus providing a means to hook or engage the bottom of the tote bin 26.
As the arms 142 and 144 reach their maximum forward travel position, the pusher blocks 168 contact the tote bin 26 as the overtravel springs 170 compress. The arm assembly 32 reverses direction as the cam follower 228 crosses the center of slot 148 in the traveler plate 140. The flippers engage the notch thus removing the tote bin from the shelf as the arms retract. The tote bin is drawn onto the platform until the aforementioned sensor near the forward retainer bars 272 senses that the tote bin is safely seated on platform 20. The pneumatic cylinders 184 are subsequently deactivated, thus dropping the arms 142 and 144 to a rest position. The belt motor 116 which drives the belt 70 causes the tote bin 26 to be brought fully onto the platform. The pneumatic cylinders 262 and 276 are activated to raise the rear crossmember 254 and the forward crossmember 270, respectively, thus causing the rear retainer bars 256 and the forward retainer bars 272 to extend over the slider bed angle plates 72 and 74. The motors 38 and 116 are switched off when the arm assembly reaches its aforementioned rearwardmost point.
FIGs. 6, 8 and 17 show a solenoid-controlled variation of the rear pop-up gate and the forward pop-up gate, respectively, as alternate embodiments of the previously described hydraulic embodiments.
The forward solenoid-controlled safety stop shown in FIG. 8, is essentially identical to the rear safety stop shown in FIG. 6 which will be described hereinafter. The forward safety stop comprises a pair of pivotal flip-up stops 300 which extend above slider bed angle plates 72 and 74. These pivotal stops 300 can be contrasted with the stops 256 or 272 which move in a purely vertical position. The flip-up stops 300 are each connected to a pop-up linkage 302. The lower ends of the two pop-up linkages are joined by means of a flip-up bushing 304. The flip-up bushing 304 is provided with a pin actuator 306 which extends through the bushing and through the ends of the linkages 302 as shown. The flip-up bushing 304 is disposed above the center channel braces 234 and is connected to the lower end of a solenoid 308 by means of a clevis or roll pin 310. The solenoid 308 is provided with a return spring 312. When the solenoid 308 is activated, the flip-up stops 300 are lowered.
FIG. 17 shows additional details of the relation between the flip-up stop 300 and the flip-up linkage 302. The linkage 302 is pivotally connected to the flip-up stop 300 at a pivot point 314. The flip-up stop 300 is pivotally connected to the slider bed angle plate 72 at a point 316, and is also provided with a rest 318. When the solenoid 308 is activated, the flip-up linkage 302 is extended upwardly thereby causing the flip-up linkage 302 to pivot downwardly about its pivot point 316. The above action causes the flip-up stop 300 to be lowered away from the top of the slider bed angle plates 72 and 74. The above relation between the flip-up linkages and the flip-up stops is consistent for both of the solenoid controlled safety stops.
The rear safety stop, shown in FIG. 6, comprises a pair of pivotal flip-up stops 280 which are identical to stops 300 previously described, and which extend above the slider bed angle plates 72 and 74. The flip-up stops 280 are each provided with a flip-up linkage 282 which are connected at their lower ends by means of a flip-up bushing 284. The flip-up bushing 284 is provided with a pin actuator 286. A solenoid 288 is attached at its lower end to the flip-up bushing by means of a roll pin 290. A return spring 292 is received on the lower end of the solenoid 288 between the solenoid and the bushing 284. The upper end of solenoid 288 is mounted on a bracket 294 which is bolted to the inside of the drive support plates 80 and 82. When the solenoid 288 is activated, the flip-up stops 280 are lowered to permit a tote bin to pass over stops 280 onto work station 28 in the same manner as described in relation to the stops 300 referred to in the prior description of FIG. 8.
FIG. 16 shows a solenoid-operated variation of the previously described pneumatic embodiment (pneumatic cylinder 184 and associated linkage) for raising the arm 144 (or 142) of the present invention. In this version, the arm 144 is provided with an arm linkage 320 which is pivotally connected thereto by means of pivot pin 322. The other end of the arm linkage 320 is pivotally connected to a drive linkage 324 which is subsequently pivotally connected to a beam linkage 326, the lower end of which is connected to the frame of the platform 20 by means of pivot pin 327. The drive linkage is mounted on one end of a connecting rod 328 whose other end is mounted on an arm channel 330. A solenoid 332 is housed within the side plates 152 and is bolted to a rear cover 334. The solenoid 332 is provided with a movable armature 335, the outer end of which is pivotally connected to the end of the rod 328 by means of a pin 337 which projects outwardly from the sides of the armature 335. A return spring 336 is received on the armature 335 between the pin 337 and the housing of the solenoid to urge the rod 328 toward the left (FIG. 16) when the solenoid is deactivated. When the solenoid 332 is activated, the drive linkage 324 moves toward the rear cover 334 thereby causing the arm 144 to move into the raised position 340. When the solenoid is deactivated, the spring 336 will return the elements to the solid line position shown in FIG. 16. An identical solenoid 332 and associated linkage is, of course, provided for the other arm 142.
Whereas the present invention has been described in particular relation to the drawings attached thereto, it should be understood that other and further modifications, apart from those shown or suggested herein, may be made within the spirit and scope of this invention. | In combination with automatic storage and retrieval system having a continuous track which supports a continuous rotating storage unit to move therearound in a horizontal direction, the rotating storage unit including a plurality of horizontally spaced shelves arranged vertically into columns, a conveyor system mounted adjacent the rotating storage unit for moving storage bins towards and away from the rotating storage unit, and an elevator mounted in a fixed position between the rotating storage unit and the conveyor system; a platform mounted in the elevator for vertical movement up and down adjacent the rotating storage unit, an extraction and insertion arm assembly slidably mounted on the platform, the arm assembly including a pair of longitudinally disposed extractor arms having the forward ends extending towards the rotating storage units, a motor for driving the arm assembly in a horizontal direction towards and away from the rotating storage unit for bin placement in and withdrawal from a preselected shelf; spring loaded flippers mounted on the forward end of each arm for removing a bin from a preselected shelf during the extraction operation; a pusher block mounted on the upper portion of each the arm for pushing a bin onto a preselected shelf during the insertion operation; a conveyor belt assembly mounted on the platform in longitudinal alignment therewith between the extractor arms for aiding the movement of a bin into or withdrawal from a preselected shelf; and retaining bars for securing a bin on the platform. | 1 |
FIELD OF INVENTION
[0001] The present invention relates to a method for can-making, particularly the top end of the can. Specifically, it relates to a method for providing the can end's pull tab with a marking, such as a logo pierced thereon, for promotional and decoration purposes, proof of purchase, product genuineness and the like, on cans, including beverage can ends.
BACKGROUND OF THE INVENTION
[0002] The conventional system for using can products, such as food and beverages cans, to provide a message, advertise or decorate on can end's pull tab is by printing, embossing or etching picture or logo on the can end's pull tab. The process to provide the logo on the can end's pull tab may be carried out by any conventional technology including, but not limit to, inks, paints, silk screens, adhesives or glues. Later, laser technology is used to produce the marking on the can end's pull tab.
[0003] In this specification, the term “marking” encompasses any form of mark provided on the pull tab, including a logo, alphanumeral, symbol, waving, topographic profile, and cut-outs through the tab. Among the earliest marking on either the pull ring tab or the end are “Lift ring to open”, “Dispose of properly”, “Do not litter” and other short messages. Since then, more creative markings in the form of colourful logo or decorative mark have been used for attractive, promotional and/or co-branding purposes, proof of purchase, genuine product identification, anti-tampering, etc.
[0004] In prior art U.S. Pat. No. 6,082,030, a moulded plastic cover is used as identification system. This identification system is costly as the prior art needs additional plastic material to be slipped into the pull tab.
[0005] In prior art U.S. Pat. No. 6,105,806, a laser device is used to burn or etch the anodised or coated aluminium tab. A plurality of coatings of aluminium material must be used to produce a colour logo or decorative item on the can end's pull tab. The material, the process and the device to produce the logo or decorative item are costly.
[0006] In prior art W00228730, a sticker-adhering device is engaged to stick the logo- or decorative item-bearing sticker onto the pull tab. The quality of the logo does not last long due to the nature of stickers.
[0007] The present invention seeks to overcome the limitations of the previous systems. One of the objects of this invention is to reduce the cost of putting a logo or words on the pull tab. The cost of stamping a pre-formed logo on a pull tab is much cheaper compare to a laser equipment.
[0008] Another object of this invention is the duration of time required to put a logo on the pull tab. For example, if a stamping process may be employed, the time required to stamp the logo on pull tab is very fast. The process will directly reduce the labour time or cost and this will increase throughput.
[0009] Still another object of the invention is to give a more lasting logo compare to some prior arts.
SUMMARY OF THE INVENTION
[0010] To achieve the aforesaid objects, it is provided in the general embodiment of the invention, a method for providing markings on a pull tab of a can end comprising piercing a logo on said pull tab to provide a logo thereon.
[0011] Preferably that the logo includes any one combination of a sign, alpha-numeral, symbol, waving and topographic profile on the pull tab and may be provided in the form of apertures, pierced out portions, perforations, punch-outs, stamped out portions and cut-outs on said pull tab forming said logo.
[0012] In a preferred embodiment, a plurality of the pull tabs may be formed on a metallic strip prior to the piercing thereon to provide the marking on each said pull tab. A plurality of the marking may also be pierced in suitably spaced apart distances on a metallic strip prior to forming pull tabs around each marking. Alternatively, the plurality of pull tabs and the corresponding marking thereunto on a metallic strip may be formed in a single press.
[0013] In another aspect of the invention, a method is provided for fabricating an easy-open can end with a pull tab provided with marling comprising the steps of:
[0014] forming said pull tab;
[0015] piercing said marking on said pull tab; and
[0016] affixing said marked pull tab onto said can end, including riveting said tab onto said can end.
[0017] In a preferred embodiment, the step of affixing the marked pull tab includes removing the pull tab formed from a plurality of such pull tabs pre-formed on a metallic strip prior to affixing said marked pull tab onto said can end by riveting means. Preferably, the method further comprises a step of folding in the edges of the pull tab to form an all-round lip.
[0018] In yet another preferred embodiment, the method further comprises the step of providing a score line outlining an aperture on the can end and affixing said pull tab at a point on the end which facilitate tearing of said score line at that point upon the lifting of the pull tab which enables a user to continue tearing along said score line to complete the opening of the aperture. An alternative to the aperture is one that is defined by the score line covering substantially the entire circumference of the end of the can.
[0019] In another alternative embodiment, the fabrication of a can end with a pull tab may be implemented in a single continuous process.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] FIG. 1 shows a top plan view of a can with the end provided with a logo pierced on the end tab according to one embodiment of the present invention.
[0021] FIG. 2 shows a top plan view of a can with another embodiment of the end provided with a logo pierced on the end tab.
[0022] FIG. 3 shows a block diagram of the method for producing the pull tab of the present invention.
[0023] FIG. 4 shows a block diagram of an alternative method for producing the pull tab of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0024] The method of providing a marking on pull tab of a can end according to the present invention may be best understood with reference to the drawings and the accompanying detailed description.
[0025] FIG. 1 shows a can end ( 1 ) of a can with the result of a logo pierced on a pull tab ( 10 ). The can end ( 1 ) comprises of a pull tab ( 10 ) rigidly attached to the can end ( 1 ), by a rivet ( 14 ) or any conventional means, and a tear strip ( 13 ) outlined by a score line ( 18 ) which can be pushed to tear open by force. The pull tab ( 10 ) includes a grip portion ( 12 ) and a fixed portion ( 11 ). The pull tab ( 10 ) is rigidly attached to can end ( 1 ) by the rivet ( 14 ) and a slit ( 15 ) is provided adjacent the fixed portion ( 11 ) of the pull tab ( 10 ) to act as a lever with the rivet ( 14 ). The pull tab ( 10 ) pivots at rivet ( 14 ) when the grip portion ( 12 ) is lifted up and the resultant leverage with the fulcrum around the rivet applies downward force by the fixed portion ( 11 ) of the pull tab ( 10 ) to open the tear strip ( 13 ). The tear strip ( 13 ) is designed in such a way that a portion of the tear strip ( 13 ) will be torn opened and the remainder of the score line ( 18 ) intact with the can end ( 1 ). Only when the tear strip ( 13 ) is pushed open completely to expose the opening or aperture, can the consumer consume the content of the can. The pull tab ( 10 ) is preferably made of metallic material that is easily processed, e.g. aluminium, aluminium alloys, steel or zinc or any other suitable material. The formation of the pull tab ( 10 ) can be done in a conversion press. The material allows the machine to easily pierce the desired logo on pull tab ( 10 ). Various of logos such as characters, icons, trademarks, etc can be stamped on the pull tab ( 10 ) for promotional purposes. A logo ( 16 ) is pierced on the pull tab ( 10 ) instead of forming a gripping aperture in the tab ( 10 ).
[0026] FIG. 2 shows a second embodiment of the invention. In this embodiment, the pull tab ( 10 ) is similar to the first embodiment in construction and affixed to the can end ( 21 ) by rivet ( 24 ) with the tear strip ( 23 ) includes substantially the entire inner circumference of the can end ( 21 ) of a can as defined by a score line ( 28 ) which can be torn to open the can end ( 21 ) of the can by pulling the pull tab ( 10 ).
[0027] The process of the invention may be implemented by an apparatus in order for producing the pull tab ( 10 ) with, for example, a conversion press having piercing system to form the desired logo on the pull tab ( 10 ) as shown in a block diagram of FIG. 3 . In a first method of producing the pull tab ( 10 ) with pierced logo, a metallic strip is fed into the forming section (S 31 ) to form the predetermined shape of tabs along the metallic strip without the marking of logo on the grip portion ( 12 ) it. The formed tab strip is then fed into a piercing section (S 32 ) to pierce the desired logo by a tooling means on the grab portion of each predetermined shape of tabs on the formed tab strip. The pierced tab strip after exiting the piercing section (S 32 ) is then fed into the riveting section (S 33 ) where pull tabs are removed from the pierced tab strip (S 34 ) and riveted onto the can end ( 21 ) of the can. A person skilled in the art may add a folding section (S 35 ) to fold in the sharp edges of the pull tab to provide an all-round lip to enhance the profile of the tab. The location of this folding section S 35 ) is interchangeable between the sections as previously mentioned.
[0028] FIG. 4 shows an alternative method for producing the pull tab ( 10 ) using a conversion press having a piercing system to form logos on the pull tab ( 10 ). In this second method, the piercing section (S 41 ) is located before the forming section process (S 42 ). The desired logos are pierced from the metallic strip in a predetermined distance between each pierced logo along said metallic strip (S 41 ) prior to entering into the forming section (S 42 ). The pierced logo will give a more lasting logo on the pull tab ( 10 ). After forming the predetermined shape of tabs, the pull tab is then rigidly mounted to the can end by riveting.
[0029] A painted metallic strip in desired colour may be used with the present invention if coloured pull tab with pierced logo are required. Similarly, the metallic strip with coated colours may also be used with the present invention.
[0030] It is to be understood that the present invention may be embodied in other specific forms and is not limited to the sole embodiment described above. However modification and equivalents of the disclosed concepts such as those which readily occur to one skilled in the art are intended to be included within the scope of the claims which are appended thereto. | A can tab with logo having a grab portion and fixed portion, pivotably attached to a can closure of a can characterised in that said can tab having a stamped out logo formed therein for promotional and decoration purposes. The can tab with logo can be affixed to said can closure adjacent the push open tear strip or pull open tear strip; or affixed adjacent the outer end of said can closure having the tear strip which is defined by the entire circumferential of said closure. | 1 |
CROSS REFERENCE TO RELATED APPLICATION
This application is a continuation application of International PCT Application No. PCT/JP2006/303497 which was filed on Feb. 24, 2006.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a technique for transferring data between processing units attaining one function or a plurality thereof and in particular to a memory control apparatus and a memory control method utilizing buffer memory effectively in a system LSI comprising a large number of processing units.
2. Description of the Related Art
A conventional system LSI has a configuration of incorporating, on a single chip, plural pieces of functional blocks, which are configured to achieve one function or a plurality thereof. These functional blocks can be regarded as a single processing unit such as a central processing unit (CPU), memory and a dedicated circuit, and a process progresses in the system LSI by exchanging signals or data between the processing units.
As the scale of such a system LSI grows, a problem emerges in exchanging signals between functional blocks, that is, the processing units.
FIG. 1 is a diagram showing the configuration of a system LSI.
Referring to FIG. 1 , in the system LSI performing data processing, plural system boards 10 (SB# 0 ), 20 (SB# 1 ) and 30 (SB# 2 ) are interconnected by way of a crossbar switch 40 (XB# 0 ). The system board 30 (SB# 2 ) comprises plural system controllers 31 (SC# 0 ) and 32 (SC# 1 ). Likewise the system board 10 (SB# 0 ) comprises a plurality of system controllers 11 (SC# 0 ) and the like, while the system board 20 (SB# 1 ) comprises a plurality of system controllers 21 (SC# 0 ) and the like.
The system controller 31 (SC# 0 ) controls a read from, and a write to, memory (DIMM) 81 , 82 , 83 or 84 by way of MAC 71 (MAC# 00 ), 72 (MAC# 1 ), 73 (MAC# 3 ) or 74 (MAC# 4 ) in accordance with an instruction from a CPU (not shown in a drawing herein) connected to either of plural CPUs 51 (CPU# 0 ), 52 (CPU# 1 ), and so on, or either of plural system controllers 32 (SC# 1 ), 11 (SC# 0 ), 21 (SC# 0 ), and so on. Further, when reading from, and writing to, the memory (DIMM) 81 , 82 , 83 or 84 , which is controlled by the system controller 31 (SC# 0 ), buffer memory 61 (M 0 ), 62 (M 1 ), 63 (M 2 ) or 64 (M 3 ), which temporarily stores data corresponding to the memory (DIMM) 81 , 82 , 83 or 84 , is utilized.
As the system LSI becomes very large, however, a large number of instructions and/or many pieces of data (i.e., data packets) sometimes converge into the same buffer memory 61 (M 0 ) 62 (M 1 ), 63 (M 2 ) or 64 (M 3 ).
FIG. 2 is a diagram for describing a phenomenon in which many instructions converge into the same buffer memory.
If a plurality of instructions (i.e., requests) from either CPU require data stored in the memory (DIMM) 81 , many instructions are converged into the buffer memory 61 (M 0 ), causing it to overflow with instructions, as shown in FIG. 2 .
In order to improve such a situation, the capacity of all the buffer memories 62 (M 1 ), 63 (M 2 ) and 64 (M 3 ), not only the buffer memory 61 (M 0 ), must be increased, and there is a resultant cost increase that makes the method impractical, and therefore the present memory 61 (M 0 ) needs to be used more effectively.
There is accordingly a technique (i.e., BUSY control technique) for issuing a BUSY signal inhibiting the transmission of an instruction or the like from a buffer memory 61 (M 0 ) or the like when the buffer memory 61 (M 0 ) or the like no longer has room to receive an instruction and/or data, that is, when the buffer memory 61 (M 0 ) or the like becomes full or nearly full. The BUSY control technique makes it possible to reduce the possibility of the buffer memory 61 (M 0 ) overflowing with instructions and the like.
Another method is to provide each of the CPUs 51 (CPU# 0 ), 52 (CPU# 1 ) and the like, which hand instructions to a single system controller 31 (SC# 0 ), with plural pieces of buffer memory, thereby making it possible to reduce the possibility of causing the buffer memory 61 (M 0 ) to overflow with instructions and the like.
However, although the above described BUSY control technique does not generate a big practical problem when a system LSI is relatively small, the distances between various LSIs, such as the distance between the system boards 10 (SB# 0 ) and 30 (SB# 2 ) and the distance between the system controllers 11 (SC# 0 ) and 32 (SC# 1 ), become longer as the system LSI becomes larger, thus elongating the transmission time between them. As a result, a “slippage” is generated between the instruction and the BUSY signal, causing a problem in which an instruction is issued to a buffer memory 61 (M 0 ) or the like that is actually unable to receive the instruction.
FIG. 3 is a diagram for describing a phenomenon called “slippage” generated between the instruction and a BUSY signal.
Referring to FIG. 3 , first, a first instruction issued from the CPU (CPU# 0 ) of the system board 10 (SB# 0 ) in step ( 1 ) (shown in the drawing; the numbers in parentheses, through ( 14 ), mean the same hereinafter), is handed over to the system controller 31 (SC# 0 ) of the system board 30 (SB# 2 ) by way of the crossbar switch 40 (XB# 0 ) in step ( 3 ), under the control of the system controller 11 (SC# 0 ) (in step ( 2 )). This prompts the system controller 31 (SC# 0 ) to access the memory (DIMM) 81 by way of the MAC 71 (MAC# 0 ) (in step ( 4 )).
If the buffer memory 61 (M 0 ) becomes full at this time, one of the BUSY signals inhibiting the transmission of an instruction or the like from the buffer memory 61 (M 0 ) (in step ( 5 )) is handed over to the system controller 11 (SC# 0 ) of the system board 10 (SB# 0 ) by way of the crossbar switch 40 (XB# 0 ) (in step ( 6 )) under the control of the system controller 31 (SC# 0 ) of the system board 30 (SB# 2 ). Then, the BUSY signal is returned to the CPU (CPU# 0 ) of the system board 10 (SB# 0 ), which initially issued the first instruction, under the control of the system controller 11 (SC# 0 ) (in step ( 7 )).
If, however, a second instruction is issued from the CPU (CPU# 0 ) of the system board 10 (SB# 0 ) and if the second instruction is handed over to the system controller 31 (SC#Q) of the system board 30 (SB# 2 ) by way of the crossbar switch 40 (XB# 0 ) (in step ( 10 )) under the control of the system controller 11 (SC# 0 ) (i.e., step ( 9 )), between the transmission of the first instruction (in step ( 1 )) and the receiving of the BUSY signal (in step ( 7 )), then the buffer memory 61 (M 0 ) is already full and the system controller 31 (SC# 0 ) is unable to receive the second instruction. This state is defined as “slippage”.
Note that, even if such a “slippage” occurs, the system controller 31 (SC# 0 ) of the system board 30 (SB# 2 ) returns a response corresponding to the first instruction from the memory (DIMM) 81 by way of the MAC 71 (MAC# 0 ) (in step ( 11 )) and the response is handed over to the system controller 11 (SC# 0 ) of the system board 10 (SB# 0 ) by way of the crossbar switch 40 (XB# 0 ) (in step ( 13 )) under the control of the system controller 31 (SC# 0 ) of the system board 30 (SC# 2 ) (i.e., step ( 12 )). Then, under the control of the system controller 11 (SC# 0 ), the response to the first instruction is returned to the CPU (CPU# 0 ) of the system board 10 (SB# 0 ), which issued the first instruction (in step ( 14 )).
Further, if a configuration is such as to generate a BUSY signal with sufficient time so as to avoid the occurrence of “slippage”, that is, if the configuration is such as to issue a BUSY signal inhibiting the transmission of an instruction or the like from a buffer memory 61 (M 0 ) and the like at the timing when the buffer memory 61 (M 0 ) or the like becomes close to full instead of completely full, a problem is generated in which the capacity of the buffer memory 61 (M 0 ) or the like is partially wasted.
Further, if a configuration is such as to provide all the CPUs with corresponding pieces of buffer memory, the required number of pieces of buffer memory increases with the size of a system LSI, thus giving rise to the problem of cost increase.
FIG. 4 is a diagram for describing the problem in the case of comprising pieces of buffer memory corresponding to all CPUs.
For example, if a single system board comprises four system controllers, with each system controller respectively comprising four CPUs, the number of pieces of buffer memory comprised by each system controller increases from four pieces corresponding to the conventional number of CPUs to sixteen pieces corresponding to sixteen CPUs, that is, between the zeroth and fifteenth. That is, the number of required pieces of buffer memory quadruples from four to sixteen.
SUMMARY OF THE INVENTION
In consideration of the situation described above, the present invention aims at providing a memory control apparatus and a memory control method that enable an effective utilization of buffer memory in a system LSI.
The present invention is contrived to adopt a configuration as follows in order to solve the above described problem.
That is, according to one aspect of the present invention, a memory control apparatus of the present invention used for controlling access to memory comprises: buffer memory for temporarily storing data stored in the memory; an instruction reception unit for receiving an instruction to the memory; a buffer memory security-dedicated use packet transmission unit for transmitting a buffer memory security-dedicated use packet for securing the capacity of memory in the buffer memory that is required by an instruction on the basis of the instruction received by the instruction reception unit; a buffer memory validation signal reception unit for receiving a buffer memory validation signal corresponding to a buffer memory security-dedicated use packet transmitted by the buffer memory security-dedicated use packet transmission unit; and an instruction execution unit for executing an instruction received by the instruction reception unit on the basis of a buffer memory validation signal received by the buffer memory validation signal reception unit.
Further, the memory control apparatus according to the present invention is desirably configured such that the instruction is generated by a central processing unit (CPU), and the memory control apparatus is a system controller.
Further, the memory control apparatus according to the present invention is desirably a large-scale integration (LSI) for use in a system LSI comprising a plurality of memory control apparatuses.
Further, according to one aspect of the present invention, a memory control method of the present invention is a method that is used for controlling an access to memory and carried out in a memory control apparatus comprising buffer memory for temporarily storing data stored in the memory, comprising: receiving an instruction to the memory; transmitting a buffer memory security-dedicated use packet for securing the capacity of memory in the buffer memory that is required by the instruction on the basis of the received instruction; receiving a buffer memory validation signal corresponding to the transmitted buffer memory security-dedicated use packet; and executing the received instruction on the basis of the received buffer memory validation signal.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagram showing the configuration of a system LSI;
FIG. 2 is a diagram for describing a phenomenon of many instructions converging into the same buffer memory;
FIG. 3 is a diagram for describing a phenomenon called “slippage” generated between the instruction and a BUSY signal;
FIG. 4 is a diagram for describing the problem in the case of comprising pieces of buffer memory corresponding to all CPUs;
FIG. 5 is a diagram for describing the flow of a memory control to which the present invention is applied; and
FIG. 6 is a diagram showing an example of a buffer memory security-dedicated use packet.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The following is a description of the preferred embodiment of the present invention by referring to the accompanying drawings.
First is an outline of the present invention.
That is, the present invention is contrived to pre-transmit a buffer memory security-dedicated use packet and pre-secure a storage zone of buffer memory and then carry out an actual accessing.
This configuration makes it possible to perform a memory control while reducing the occurrence of “slippage” drastically without increasing the quantity of buffer memory.
FIG. 5 is a diagram for describing the flow of a memory control to which the present invention is applied.
Referring to FIG. 5 , first, the CPU (CPU# 0 ) of a system board 10 (SB# 0 ) issues a first buffer memory security-dedicated use packet corresponding to the first instruction (in step ( 1 )).
FIG. 6 is a diagram showing an example of a buffer memory security-dedicated use packet.
Referring to FIG. 6 , the buffer memory security-dedicated use packet is made of 32 bits ( 0 through 31 ), in which the zeroth through eleventh-bit fields store a reserve ID (RSVID); the twelfth through fifteenth-bit fields store the system board number (TARGET) of the addressee, that is, a target; of the sixteenth through eighteenth-bit fields, the sixteenth-bit field stores BANK-ID and the seventeenth to eighteenth-bit fields store MAC-ID; and the twenty-fourth through thirtieth-bit fields store an operation code (OPC).
Returning the description to FIG. 5 , the first buffer memory security-dedicated use packet issued from the CPU (CPU# 0 ) of a system board 10 (SB# 0 ) is handed to the system controller 31 (SC# 0 ) of a system board 30 (SB# 2 ) by way of a crossbar switch 40 (XB# 0 ) (in step ( 3 )) under the control of the system controller 11 (SC# 0 ) (step ( 2 )).
This prompts a system controller 31 (SC# 0 ), having received the first buffer memory security-dedicated use packet, to secure the capacity of memory in buffer memory 61 (M 0 ) that is required by the first instruction and also to increment a counter. Then, if the fact that the buffer memory 61 (M 0 ) becomes full is validated on the basis of the information stored in the first buffer memory security-dedicated use packet, one of the buffer memory security signals indicating that the buffer memory 61 (M 0 ) is likely to be full is handed to the system controller 11 (SC# 0 ) of a system board 10 (SB# 0 ) as the ACK (i.e., acknowledge) for receiving the first buffer memory security-dedicated use packet (in step ( 4 )) by way of the crossbar switch 40 (XB# 0 ) (step ( 5 )) under the control of the system controller 31 (SC# 0 ) of the system board 30 (SB# 2 ). Then, the buffer memory security signal is returned to the CPU (CPU# 0 ) of the system board 10 (SB# 0 ), which originally issued the first buffer memory security-dedicated use packet, under the control of the system controller 11 (SC# 0 ) (in step ( 6 )).
Then, the first instruction is issued from the CPU (CPU# 0 ) of the system board 10 (SB# 0 ) (in step ( 7 )) and is handed to system controller 31 (SC# 0 ) of the system board 30 (SB# 2 ) by way of the crossbar switch 40 (XB# 0 ) (in step ( 9 )) under the control of the system controller 11 (SC# 0 ) (step ( 8 )). This prompts the system controller 31 (SC# 0 ) to validate that the first instruction is the instruction corresponding to the first buffer memory security-dedicated use packet and to access memory (DIMM) 81 by way of a MAC 71 (MAC# 0 ) (in step ( 10 )).
Then, the system controller 31 (SC# 0 ) of the system board 30 (SB# 2 ) returns a response corresponding to the first instruction from the memory (DIMM) 81 by way of the MAC 71 (MAC# 0 ) and also decrements the counter (in step ( 11 )); the response corresponding to the first instruction is handed to the system controller 11 (SC# 0 ) of the system board 10 (SB# 0 ) by way of the crossbar switch 40 (XB# 0 ) (in step ( 13 )) under the control of system controller 31 (SC# 0 ) of the system board 30 (SB# 2 ) (in step ( 12 )); and the response corresponding to the first instruction is returned to the CPU (CPU# 0 ) of the system board 10 (SB# 0 ) under the control of the system controller 11 (SC# 0 ) (step ( 14 )).
Meanwhile, after issuing the first buffer memory security-dedicated use packet in the above described step ( 1 ), when a second buffer memory security-dedicated use packet corresponding to a second instruction is issued from the CPU (CPU# 0 ) of the system board 10 (SB# 0 ) (in step ( 15 )) and the second buffer memory security-dedicated use packet is handed to the system controller 31 (SC# 0 ) of the system board 30 (SB# 2 ) by way of the crossbar switch 40 (XB# 0 ) (in step ( 17 )) under the control of the system controller 11 (SC# 0 ) (step ( 16 )), it is possible to validate that the capacity of memory in the buffer memory 61 (M 0 ) is going to be full due to receiving the first buffer memory security-dedicated use packet even if the buffer memory 61 (M 0 ) is not yet full.
A preferred embodiment of the present invention has so far been described. The above described embodiment of the present invention can be implemented, as one function of the memory control apparatus, by using hardware, firmware such as a digital signal processing (DSP) board or a CPU board, or using software.
Further, the memory control apparatus to which the present invention is applied may be a single apparatus, a system or integrated apparatus consisting of a plurality of apparatuses, or a system in which the processing is carried out by way of a network such as a local area network (LAN) or a wide area network (WAN), provided that the function of the memory control apparatus is carried out, in lieu of the present invention being limited by the above described embodiment.
The present invention may be implemented by employing a system comprising a CPU, memory such as read only memory (ROM) and random access memory (RAM), an input apparatus, an output apparatus, an external recording apparatus, a media drive apparatus, and a network connection apparatus, all of which are interconnected by a bus. That is, it is obvious that the present invention can also be implemented by providing the memory control apparatus with memory, such as ROM and RAM, an external recording apparatus, and a portable recording medium, all of which store the program code of the software implementing the system according to the above described embodiment, so that the computer of the memory control apparatus reads and executes the program code.
In such a case, the program code read from the portable recording medium and the like is regarded as implementing the new function of the present invention, and the portable recording medium and the like recording the program code are regarded as the constituent of the present invention.
The portable recording medium for supplying the program code can use, for example, a flexible disk, a hard disk, an optical disk, a magneto optical disk, a CD-ROM, a CD-R, a DVD-ROM, a DVD-RAM, a magnetic tape, a nonvolatile memory card, a ROM card, and various recording media recorded by way of a network connection apparatus (i.e., a telecommunications line in other words) such as electronic mail and personal computer (PC) communications.
Further, the function of the above described embodiment is implemented by a computer (i.e., an information processing apparatus) executing the program code read onto the memory and, in addition, the function of the above described embodiment is also implemented by the processing resulting from the operating system (OS) and the like working in the computer carrying out a portion of the actual processing or the entirety thereof on the basis of the instruction of the program code.
Furthermore, a program code read from a portable recording medium and/or a program (and data) provided by a program (and data) provider(s) are (or, is) written to memory comprised by a function extension board inserted into a computer, or by a function extension unit connected to the computer, and then a portion of the actual processing or the entirety thereof is executed by the CPU and the like comprised by the function extension board or a function extension unit on the basis of the instruction of the program code, and thereby the function of the above described embodiment can be implemented.
That is, the present invention may adopt various configurations or forms within the scope thereof, in lieu of being limited to the above described embodiment. | A memory control apparatus and a memory control method are provided to enable an effective utilization of buffer memory in a system LSI by comprising buffer memory for temporarily storing data stored in memory, and comprising the processes of: receiving an instruction to the memory; transmitting a buffer memory security-dedicated use packet for securing the capacity of memory in the buffer memory required by the instruction on the basis of the received instruction; receiving a buffer memory validation signal corresponding to the transmitted buffer memory security-dedicated use packet; and executing the received instruction on the basis of the received buffer memory validation signal. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims priority to U.S. patent application Ser. No. 11/287,884, entitled Motion Detector Module, filed Nov. 26, 2005, which claims priority to the following provisional patent applications: U.S. Provisional Application No. 60/631,100 entitled Modular Motion Detector, filed Nov. 26, 2004; U.S. Provisional Application No. 60/654,321 entitled Modular Motion Detector, filed Feb. 19, 2005; and U.S. Provisional Application No. 60/715,456 entitled Motion Detector Module, filed Sep. 10, 2005. All of the aforementioned prior applications are incorporated herein by reference in their entirety.
BACKGROUND OF THE INVENTION
Motion detectors are security system components that can trigger an alarm in the event of a burglary, fire or other critical conditions. Motion detectors are also energy conservation components, which can shut-off lights or disable other power consuming devices when there is no perceivable activity. Motion detectors utilize a variety of technologies, such as video cameras, ultrasonic emitter and detector combinations and infrared sensors in order determine if movement is occurring within a target area.
SUMMARY OF THE INVENTION
One drawback to conventional motion detectors is the necessity of custom installation. A motion detector typically requires physical and electrical connection to an existing or newly installed junction box. Although motion detectors are available that plug into conventional outlets, the choice of location and function is limited, and protrusion from the outlet is undesirable.
A modular motion detector is configured to be removably mounted to a wiring module. The wiring module can be either wired for a single throw or a three-way switch. As such, any of a switch function, a dimmer switch function or a motion detector function can be advantageously implemented without rewiring and without requiring professional installation. Wiring modules and functional modules that implement switch or dimmer switch functions are described in U.S. Pat. No. 6,884,111 entitled Safety Module Electrical Distribution System, assigned to ProtectConnect, Irvine, Calif. and incorporated by reference herein.
One aspect of a motion detector is a housing having a front side and a back side. Conductors are disposed on the back side so as to electrically connect to a wiring module installed within an electrical box. An infrared (IR) sensor is mounted within the housing and configured to receive IR radiation focused from a lens disposed on the front side. The IR sensor generates a sensor signal in response to motion across the field-of-view of the lens. A controller is responsive to the sensor signal so as to generate a switch signal. A relay is responsive to the switch signal so as to switch an electrical power source connecting to an electrical power load via the conductors and the wiring module.
Another aspect of a motion detector is an electrical box configured to accept electrical conductors in communications with a power source and a power load. A wiring module having a wiring side and a functional side is mounted within the electrical box. A motion detector module having a front side and a back side is removably plugged into the wiring module. The wiring module wiring side terminates the electrical conductors, and the functional side has wiring module contacts electrically connected to the terminations. The motion detector module front side has a lens for receiving IR radiation, and the back side has motion detector module contacts that are removably and electrically connected to the wiring module contacts. The motion detector module is responsive to motion within the field-of-view of the lens so as to connect the power source with the power load via the motion detector module contacts. In one embodiment, the motion detector may further include a relay disposed within the motion detector module. The relay has a switch movable between a closed position connecting the power source to the power load and an open position disconnecting the power source from the power load. The switch moves between open and closed positions only upon the zero-crossing of the AC power source, i.e. when the power source voltage or current changes polarity.
A further aspect of a motion detector routes an electrical power source and an electrical power load to an electrical box. A wiring module is mounted within the electrical box, and the power source and load are terminated at the wiring module. A motion detector module is plugged into the wiring module so as to allow the motion detector module to communicate with the power source and load via the wiring module. The power source is switched to the load in response to motion in the field-of-view of the motion detector module. In one embodiment, a switch module for manually switching the power source to the load is unplugged from the wiring module and interchanged with the motion detector module.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1A-B are front perspective views of a motion detector module unplugged from and plugged into a wiring module, respectively;
FIGS. 2A-C are front, back and exploded perspective views, respectively, of a motion detector module;
FIGS. 3A-B are front and back perspective views, respectively, of a front shell;
FIGS. 4A-B are front and back perspective views, respectively, of a back shell;
FIGS. 5A-B are front and back perspective views, respectively, of a cover assembly;
FIGS. 6A-C are front, back and exploded perspective views, respectively, of a printed circuit board (PCB) assembly;
FIG. 7 is a functional block diagram of a motion detector module; and
FIG. 8 is a flow diagram for a main control unit (MCU) of the motion detector module.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIGS. 1A-B illustrate a motion detector module 200 unplugged from and plugged into a wiring module 100 . The wiring module 100 installs within a conventional electrical box (not shown) using box mounts 110 that attach to an electrical box with fasteners 112 . The wiring module 100 physically mounts and electrically connects a variety of functional modules, including a motion detector module 200 , to a power source and a power load routed to an electrical box. The motion detector module 200 advantageously plugs into and out of the wiring module 100 without professional installation and without exposure or access to electrical system wiring. Attachment ears 310 attach the motion detector module 200 to module mounts 120 with corresponding fasteners 122 .
As shown in FIGS. 1A-B , the motion detector module 200 functions with the wiring module 100 as an electrical power switch responsive to motion within the field-of-view of a sensor lens or to a manually operated actuator, both mounted on the front of the motion detector module 200 . The motion detector module 200 mounts generally flush with a wall surface, with only an aesthetically pleasing curved cover assembly 500 protruding from the wall. A motion detector module 200 may be configured to be wall-mounted or ceiling-mounted. Further, the motion detector module 200 can be adapted for electrical power distribution applications within buildings, automobiles or boats, to name just a few.
FIGS. 2A-C illustrate a motion detector module 200 having a housing 205 with a cover assembly 500 on a front side 201 , shielded plugs 210 and a ground bar 620 on a back side 202 and attachment ears 310 on diagonally opposing comers. The cover assembly 500 has a sensor lens 510 , an indicator lens 520 and an actuator 530 . The shielded plugs 210 and the ground bar 620 are configured to physically and electrically connect the motion detector module 200 to a wiring module 100 ( FIGS. 1A-B ). In particular, the motion detector module 200 switches electrical power across the shielded plugs 210 , functioning, for example, as a SPST switch or as a three-way switch in response to motion within its field-of-view. The ground bar 620 provides a ground connection and functions as a key to orient the motion detector module 200 when plugging into the wiring module 100 ( FIGS. 1A-B ). The attachment ears 310 accept fasteners 122 that secure the motion detector module 200 to the wiring module 100 ( FIGS. 1A-B ).
As shown in FIG. 2C , the housing 205 ( FIGS. 2A-B ) has a front shell 300 and a back shell 400 that enclose a printed circuit board (PCB) assembly 600 . The front shell 300 and the back shell 400 are held together with fasteners 260 . The PCB assembly 600 provides the electronics to detect IR radiation, determine motion and switch electrical power, among other functions. The front and back shells 300 , 400 are described in detail with respect to FIGS. 3-4 , below. The cover assembly 500 is described in detail with respect to FIGS. 5A-B below. The PCB assembly 600 is described in detail with respect to FIGS. 6A-B , below. The motion detector module functions are described with respect to FIGS. 7-8 , below.
FIGS. 3A-B illustrate a front shell 300 having an outside face 301 , an inside face 302 , attachment ears 310 , a lens cavity 320 , a sensor window 330 , adjustment apertures 340 , flexors 350 , a post aperture 360 and fastener holes 370 . The attachment ears 310 are located at diagonally opposite comers for mounting the motion detector module 200 ( FIGS. 1A-B ) to a wiring module 100 ( FIGS. 1A-B ), as described above. The lens cavity 320 physically supports and optically accommodates the sensor lens 510 ( FIGS. 5A-B ). The sensor window 330 is located proximate to and transfers light to a PIR sensor 710 ( FIG. 6A ). The adjustment apertures 340 accommodate adjustment screws 230 ( FIG. 2C ) that couple to trim pots 730 ( FIG. 6A ) through the front shell 300 , so that adjustments, described below, are accessible from the module front side 201 ( FIG. 2A ). The flexors 350 contact corresponding stops 532 ( FIG. 5B ) to provide tactile feedback to the actuator 530 ( FIG. 2C ). The post aperture 360 accommodates the switch post 534 ( FIG. 5B ), which physically actuates a mini-switch 630 ( FIG. 6A ) in response to a pressing of the actuator 530 ( FIG. 2C ). The fastener holes 370 accommodate the fasteners 260 ( FIG. 2C ) that attach the front shell 300 to the back shell 400 ( FIGS. 4A-B ).
FIGS. 4A-B illustrate a back shell 400 having an inside face 402 , an outside face 401 , plug shields 410 , a ground bar aperture 420 and fastener holes 430 . The plug shields 410 provide a nonconductive shield portion of the shielded plugs 210 ( FIG. 2B ). Specifically, the plug shields 410 completely surround all sides of the power PCB prongs 610 ( FIG. 6B ). The ground bar aperture 420 allows a ground bar 620 ( FIG. 6B ) to protrude through the back shell 400 , providing a ground contact with the wiring module 100 ( FIGS. 1A-B ). The fastener holes 430 allow fasteners 260 ( FIG. 2C ) to fixedly attach the back shell 400 to the front shell 300 .
FIGS. 5A-B illustrate a cover assembly 500 having a sensor lens 510 , an LED lens 520 and an actuator 530 . The sensor lens 510 is adapted to receive and focus optical radiation for the PIR sensor 710 ( FIG. 6A ). The LED lens 620 indicates motion detection when illuminated by the LED 735 ( FIG. 6A ). The actuator 530 manually initiates the motion detector switching function, as described with respect to FIG. 8 , below, and is removable to provide access to adjustment screws 230 ( FIG. 2C ).
FIGS. 6A-C illustrate a printed circuit board (PCB) assembly 600 having a control PCB 601 and a power PCB 602 . The control PCB 601 has a pyroelectric infrared (PIR) sensor 710 , a manual control jumper 725 , adjustment pots 730 , an LED 735 and a mini-switch 740 , which are all functionally described with respect to FIGS. 7-8 , below. The power PCB 602 has a DC power supply 750 and a relay 770 , also functionally described with respect to FIGS. 7-8 , below. A control PCB connector 630 mates with a power PCB connector 640 to mechanically and electrically connect the PCB's 601 , 602 in a piggyback configuration, as described in further detail with respect to FIG. 7 , below. The power PCB also has power prongs 610 and a ground bar 620 , also described in further detail with respect to FIG. 7 , below.
FIG. 7 illustrates a functional block diagram 700 for a motion detector module 200 ( FIGS. 1A-B ), which is divided between a control PCB 601 and a power PCB 602 , both described with respect to FIGS. 6A-C , above. The control PCB 601 includes a PIR sensor 710 , a two-stage amplifier 715 , a main control unit (MCU) 720 , a manual control jumper 725 , lux, delay and sensitivity adjustments 730 , an LED 735 and a mini-switch 740 . The power PCB 602 includes a DC power supply 750 , an AC tap 755 , a relay driver 760 and a relay 770 .
As shown in FIG. 7 , on the control PCB 601 , the PIR sensor 710 is responsive to optical radiation at IR wavelengths so as to detect motion, as is well-known in the art. The two-stage amplifier 715 is responsive to the PIR sensor 710 output so as to provide a motion detected output to the MCU 720 . A sensitivity adjustment pot 730 sets the gain for the final stage of the two-stage amplifier 715 so as to determine motion sensitivity. The MCU 720 processes the PIR sensor 710 output along with inputs from the mini switch 740 , the manual control jumper 725 and settings from the lux and delay adjustment pots 730 to actuate the relay 770 , as described with respect to FIG. 8 , below. The MCU 720 also flashes the LED 735 to indicate motion detection, also described below. In one embodiment, the MCU is an EM78P458 8-bit microcontroller from Elan Microelectronics Corp., Taipei, Taiwan.
Also shown in FIG. 7 , on the power PCB 602 , the DC power supply 750 converts the AC power inputs 610 , 620 to DC voltage for the electronics on both PCBs 601 , 602 . An AC tap 755 provides a low-current sample of the AC power waveform to the MCU 720 , advantageously allowing the MCU 720 to actuate the relay 770 at zero-crossings of the AC power waveform, i.e. when the AC voltage or current change polarity, so as to minimize relay arcing. The relay driver 760 is responsive to a MCU 720 switch signal so as to provide sufficient drive current to actuate the relay 770 . The relay 770 selectively connects and disconnects the power prongs 610 so as to switch power on and off to a load. In particular, the relay 770 has a switch movable between a closed position connecting power to the load and an open position disconnecting power from the load.
FIG. 8 illustrates the functional flow 800 of the MCU 720 ( FIG. 7 ), which determines at least a portion of the operational characteristics of the motion detector module 200 ( FIGS. 1A-B ). When power is first applied to the motion detector module 200 ( FIGS. 1A-B ), the MCU performs a power-on initialization sequence 805 . In a status step 810 , the MCU determines whether the manual control jumper 725 ( FIG. 7 ) is present and whether the mini switch 740 has been pushed. In an operating mode step 820 , if the manual control jumper is present, the motion detector module will be in auto mode 830 - 890 , otherwise it will be in manual mode. In manual mode, if the mini switch has been pushed and the previous mode was off, then the new mode is on and the relay is actuated to apply power to the load 821 . Likewise, if the previous mode was on, then the new mode is off and the relay is actuated to remove power to the load 823 . Otherwise, no action is taken and the status step 810 is repeated.
As shown in FIG. 8 , in auto mode, motion detection is determined 830 . If motion is not detected, load on/off is checked 842 . If the load is not on, the status step 810 is simply repeated. Otherwise, the delay time from the last motion detection is determined 844 . If the delay time as set by the delay adjustment 730 ( FIG. 7 ) has not been exceeded, then the MCU simply returns to the status step 810 . If the delay time has been exceeded, then the load is turned off 846 and the status step 810 is repeated.
Also shown in FIG. 8 , if motion is detected 830 , the LED 735 ( FIG. 7 ) is flashed 850 . In one embodiment, the LED is turned on for 10 ms. If the load is on 860 , the load on timer is reset 890 and the status step 810 is repeated. If the load is off 860 , the ambient light brightness is checked 870 relative to the lux adjustment 730 ( FIG. 7 ). If the ambient light is sufficiently bright, the status step 810 is simply repeated. Otherwise, the load is turned on 880 , the load on timer is reset 890 , and the status step 810 is repeated. The ambient light brightness check assumes the load is, for example, an artificial light source. In other applications, the load could be, for example, an alarm or other security alert, and the lux adjustment could be set so that ambient light brightness would be irrelevant.
A motion detector module has been disclosed in detail in connection with various embodiments. These embodiments are disclosed by way of examples only and are not to limit the scope of the claims that follow. One of ordinary skill in art will appreciate many variations and modifications. | A motion detector comprises a housing having a front side and a back side. Conductors are disposed on the back side so as to electrically connect to a wiring module installed within an electrical box. An infrared (IR) sensor is mounted within the housing and configured to receive IR radiation focused from a lens disposed on the front side. The IR sensor generates a sensor signal in response to motion across the field-of-view of the lens. A controller is responsive to the sensor signal so as to generate a switch signal. A relay is responsive to the switch signal so as to switch an electrical power source connecting to an electrical power load via the conductors and the wiring module. | 6 |
BACKGROUND
This invention relates to semiconductor devices, and more specifically to polycrystalline silicon resistors with high, and close tolerance, resistance values.
In an integrated circuit (IC) or other device formed on a semiconductor substrate, resistors may be formed from several hundred to several thousand angstroms of thin film deposited over insulation on the surface of the substrate, and connected between two conductors. In integrated circuit devices, such isolated resistors are useful for their range of sheet resistance values, low temperature coefficients, freedom of positioning on the surface of the IC, electrical isolation from other elements of the circuit, and trimmability by a focused heat source cutting or physically evaporating a pattern of the film to increase its resistance and to improve resistance tolerance precision.
Resistive thin films are often formed of amorphous silicon, doped with chromium and traces of carbon, boron or other elements for resistance and temperature coefficient optimization. Thin film resistors of this nature are usually deposited by the well-known technique of sputtering. In sputtering, a high intensity radio frequency field is applied, through electrodes or a coil, to a low pressure gas, from which a "glow discharge" of ions bombards or "sputters" a target composed of resistor constituents in appropriate proportions, dislodging atoms from the target to condense and form a thin film on a substrate positioned nearby. Even for use as a thin film resistor, silicon must have its conductivity increased by doping, with either P type (e.g., boron) or N type (e.g., arsenic phosphorous) impurities, for hole or electron flow, respectively. Silicon can be doped with impurities while or after being deposited as a film, but whenever doping is done, the need to control doping concentration precisely makes it difficult to obtain accurate resistance values. The sputtering equipment and process are difficult to control, leaving a need for an alternate technique of providing thin film resistors.
Thin film resistors can also be formed of polycrystalline silicon deposited by conventional CVD techniques. Polycrystalline silicon is an aggregation of small, randomly oriented grains of silicon crystals whose lattices mismatch, forming boundaries between grains. Solid State Electronics, Vol. 27, No. 11, pp. 995-1001, 1984, reports that resistive thin film dopant diffusion can be controlled by combining acceptor (e.g., boron) and donor (e.g., phosphorus) doping to form a high resistance or "semi-insulating" resistor. In this prior art process, a polycrystalline silicon film is deposited on insulating oxide over a silicon substrate, blanket implanted with phosphorous atoms, annealed a first time, masked and etched, forming a pattern of polycrystalline silicon resistor areas, which are then implanted with boron atoms to a concentration no greater than that of the phosphorus atoms. The doubleimplanted film is annealed a second time, at 1000° C. for at least 10 minutes, repairing implantation damage and increasing polycrystalline silicon grain size, but more importantly thermally activating dopants at an approximately predictable rate, so that practically all boron atoms become associated with, and are neutralized or deactivated by, phosphorus atoms, which offsets the conductivity, or increases the resistance, of the double-implanted resistor areas. After neutralization, resistor values are 10 3 to 10 4 times higher than values of conventional polycrystalline silicon thin film resistors doped with the same concentration of phosphorus. However, the resistance value tolerance remains wider than desired.
SUMMARY
This invention takes advantage of the effect of twice doped silicon resistance increasing with increasing anneal temperature, to trim high resistance films to closer resistance value tolerances, by using a laser or other focused heat source for a dynamic feedback controlled third anneal.
Polycrystalline silicon thin films are deposited, doped and annealed a first time, patterned, and doped a second time conventionally, but annealed a second time at a reduced temperature to limit the increase in resistance to less than the value ultimately intended. Then, the thin film is covered with passivation, through which contacts are formed with conductive leads, and connected to an external resistance measuring device. The resistance is monitored while the thin film is annealed a third time by a locally focused heat source, such as a laser beam, until the measuring circuit detects that the resistance has reached the intended final value, and turns off the focused heat source. The twice annealed resistor value tolerance is improved by the individually controlled third anneal.
BRIEF DESCRIPTION OF THE DRAWING
FIGS. 1 through 6 are cross-sections illustrating steps in a sequence for forming resistors according to this invention.
DETAILED DESCRIPTION
The present invention provides high resistance thin film polycrystalline silicon resistors with improved (closer) tolerance resistance values. Referring to FIG. 1, the process preferably begins with a semiconductor wafer 10 having an upper surface 11 covered with a dielectric layer such as silicon dioxide 12, which is in turn covered with several hundred to several thousand angstroms of chemical vapor deposited polycrystalline silicon film 13.
Next, polycrystalline silicon film 13 is doped a first time by ion implantation or by thermal predeposition of N type atoms (e.g. phosphorous). N- doped film 13 and wafer 10 are annealed for example, in a suitable furnace at approximately 1000° C. for ten minutes, to activate N type dopant atoms.
Referring to FIG. 2, photoresist is applied and patterned to form mask M1 protecting (once doped and annealed) film 13 areas 14 designated for formation of conductors or resistors, while exposed areas are etched, leaving thin film pattern 14. Alternatively, film 13 can be left unpatterned and intact until after the second doping and annealing steps below.
If desired, selected areas of unpatterned film 13 or of patterned film 14 can be preserved in the once doped conductive state by employing a second photoresist mask M2, FIG. 3, to block a subsequent second doping. With or without optional mask M2, exposed film areas 15 are then doped with P type atoms (e.g. boron) by ion implantation or by thermal predeposition, to a concentration not exceeding the N type (phosphorus) dopant concentration. Alternatively, film 13 can be doped first with P type atoms, annealed, and doped second with N type atoms. After doping, mask M1 or M2 is removed.
Twice-doped film 15 and wafer 10 are annealed a second time to activate P type (boron) atoms to recombine with N type (phosphorus) atoms by the deactivation mechanism referred to in the prior art reference. However, the second anneal temperature is limited so that film 15 resistance increases to no closer than the maximum tolerance variation from the value ultimately intended.
Then, twice doped, twice annealed, and patterned film 15 is covered by transparent silicon oxide or semitransparent silicon nitride passivating layer 16, FIG. 4, formed, for example, by chemical vapor deposition. Next, photoresist is deposited and patterned to form mask M3 over passivating layer 16, exposed areas of which are then etched, opening contact holes 17 down to thin film resistor area 15.
Next, a conductive metallization layer is deposited and etched to form a metallization pattern including contacts 18 and 19, FIG. 5.
Contacts 18 and 19 are connected through conductive leads, not shown, to an external resistance measuring device such as an ohmmeter, curve tracer, test computer, or the like, not shown, which monitors the resistance of resistor 15 continuously and in a well known fashion to control and direct a focused heat source 25 such as an electron beam or laser through passivation 16 to scan and locally heat resistor 15 until the desired resistance value is attained. In contrast to prior art trimming techniques, this resistance adjustment or "trimming" by focused heat does not cut or eliminate the thin film.
Typically, an integrated circuited device includes many such thin film resistors 15, and the third anneal resistance "trimming" operation is repeated by switching the resistance monitoring device and focused heat source 25 to another resistor 15.
A preferred embodiment has been illustrated, of which modifications and adaptations within the scope of the invention will occur to those skilled in the art. The invention is limited only by the scope of the following claims. | A process of providing semi-insulating thin film resistors with closer tolerance values by furnance-annealing the film to increase is resistance to less than the final intended value, and then focused heat source-annealing the film to within a close tolerance of the final intended value. | 8 |
BACKGROUND OF THE INVENTION
The invention relates to a net, especially a spacing net, surface protection net or the like, having strands which intersect one another.
The nets mentioned above are mainly used as spacing nets or protective nets for highly finished surfaces. They are formed from two layers of strands which intersect one another. For the purpose of pack aging goods in a safe manner or spacing apart articles, it is required that the net has a certain thickness. In prior art nets, the strands are provided with a cross section of appropriately great dimension to meet thickness requirements. These type of nets require a high expenditure of material. Besides, they only have a very limited resilience.
SUMMARY OF THE INVENTION
It is, therefore, the object of the invention to provide a net of the species described in the foregoing which meets especially the spacing and surface protection requirements.
According to the invention, this object is accomplished by arranging the strands of the net in three different planes and orienting the strands of two planes equidirectionally. As a result, a relatively great thickness of the net is obtained with a small cross section of the individual strands (minimum expenditure of material), and the resilience of the net is improved.
Preferably, the strands of two outward planes (outer strands) extend parallel to one another, so that the outer strands do not cross one another, and a uniform thickness of the net is ensured.
In a special embodiment of the invention, the outer strands of the outer p lanes extend parallel and are offset to one another in the longitudinal direction of the strands (inner strands) of the median plane. This results in a surprisingly good resilience of the net.
It is of advantage that especially the inner strands are elastically deformable in such a way that the outer strands are movable in the direction of the median plane of the inner strands. When the outer strands are subjected to stress in the direction towards the median plane and thus towards the inner strands, the outer strands shift, so to speak, into the median plane, that is to say between the inner strands. The good resilience of the net is a result of the elastic deformation of at least the inner strands. In the end, it is thus ensured that the goods enclosed in the netting are well padded, or that the distance between two articles which are separated by the net can be varied.
The resilience of the net depends in particular on the distance by which the outer strands of different outer planes are offset relative to one another in the longitudinal direction of the inner strands. This is why said distance is accurately defined in accordance with the invention. The relation is such that, the smaller the distance between the outer strands of different planes, the firmer the springiness.
If the distance between the outer strands in different planes equals half of the distance between two adjacent strands in one plane, as it is provided in accordance with a special embodiment, the springiness of the net is particularly soft. Of course, this is the case especially when the distances between adjacent outer strands are equal in both outer planes.
It is in particular accordance with the invention to use the net as a spacing means between plate-like articles, especially plates of latent heat storage devices. The thickness of the se plates changes in response to temperature variations. The resulting changes of the distance between the plates can be compensated by the net according to the invention because it is able, as a result of its design in accordance with the invention, to elastically change its thickness to the extent necessary.
Further features of the invent ion and their advantages will be apparent from the dependent claims and the description of the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be described hereinafter, in detail, with reference to several preferred exemplary embodiments and the accompanying drawings, in which:
FIG. 1 is a fragmentary schematic and enlarged top plan view of a net,
FIG. 2 is a side view of the net of FIG. 1,
FIG. 3 is a side view of the net of FIG. 1 which is deformed resiliently,
FIG. 4 is a side view of a second exemplary embodiment of the net,
FIG. 5 is a side view of the net of FIG. 4 which is deformed resiliently,
FIG. 6 is a side view of a third exemplary embodiment of the net,
FIG. 7 is a side view of a fourth exemplary embodiment of the net,
FIG. 8 is a side view of a fifth exemplary embodiment of the net,
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
A net 10 which is illustrated in FIGS. 1 to 3 has three different planes 11, 12, 13 which are indicated by dash-dot lines in the Figures. These planes 11, 12, 13 extend parallel to one another. The outer planes 11, 13 are arranged on opposite sides of the median plane 12.
The inner strands 14 extend essentially in an equally spaced relationship in the median plane 12, whereas the outer strands 15, 16 are arranged in the outer planes 11, 13 so as to extend equidirectionally. As is particularly evident from FIG. 1, the outer strands 15, 16 intersect the inner strands 14, preferably at an angle which is less or greater than 90°, especially at an angle of 75°. The outer strands 15, 16 are connected to the inner strands 14 at the points of intersection.
The outer strands 15, 16 are distributed over the outer planes 11, 13. The outer strands 15 in the plane 11 extend parallel to one another, just like the outer strands 16 in the plane 13. Within every plane 11, 12, 13, the inner strands 14 or outer strands 15, 16 are spaced out at equal distances. The outer strands 15 and 16 of the different outer planes 11 and 13 are oriented to extend parallel.
The inner strands 14 and the outer strands 15, 16 extend in an essentially rectilinear manner which is favourable with respect to manufacture of the net and with respect to the mechanical properties of the net 10. As a result, the net 10 exhibits a good stability when it .is subjected to a pulling force in the direction of the outer strands 15, 16 or inner strands 14.
In the exemplary embodiments of FIGS. 1 to 7, the parallel outer strands 15, 16 of the different outer planes 11, 13 are disposed offset to one another in the longitudinal direction of the inner strands 14. This is particularly important for the resilience of the net 10. A force which is exerted on the outer strands 15 of the outer plane 11 in the direction towards the plane 12 effects a relative movement of the outer strands 15, 16 and a deformation of the inner strands 14. The outer strands 15, 16 move in the direction of the inner strands 14 while, at the same time, the inner strands 14 are deformed elastically, such that they extend .in a wave-like manner (FIGS. 3 and 5). As a result of this relative movement, the outer planes 11, 13 and the central plane 12 overlap, so to speak. In other words, the outer planes 11, 13 move towards one another and rest against one another when the net 10, 17, 18, 19 assumes a "blocked" position in which it can not be compressed any further.
FIGS. 3 and 5 illustrate the relative movement of the net 10, 17 when it is subjected to stress between two plane surfaces which are not shown. In these Figures, the net 10, 17 is in an almost "blocked" position, in which the distance between said surfaces equals the sum of the diameters of two strands (inner strands 14 or outer strands 15, 16). The resilience of the net 10 essentially depends on the distance by which the outer strands 15 of the outer plane 11 are offset relative to the outer strands 16 of the outer plane 13. In the case of a small distance (see FIGS. 1 to 3), the springiness of the net 10 is relatively firm.
If, on the other hand, the distance between the outer strands 15, 16 of different outer planes 11, 13 is greater, specifically if the outer strands 15 or 16 of the one plane 11 or 13 are evenly staggered relative to the outer strands 15 or 16 of the other outer plane 11 or 13, as in the exemplary embodiment of FIGS. 4 and 5, the springiness of a net 17 is soft.
In accordance with the invention, the appropriate definition of this distance alone makes it possible to essentially control the resilience of the net. For this purpose, it would also be possible to arrange the outer strands 15, 16 within the outer planes 11, 13 in a way which is different to the ones illustrated in the drawings.
In the exemplary embodiment of FIG. 6, the distances between the outer strands 15 and 16 of the respective outer plane 11 or 13 are equal, but the outer plane 13 has twice as many strands 16 as the outer plane 11. The distances between the outer strands 16 of the outer plane 13 are defined such that two of the outer strands 16 of the outer plane 13 are always disposed between two adjacent outer strands 15 of the outer plane 1. In this exemplary embodiment of a net 18, the inner strands 14 are also deformed in a wave-like manner when the net is subjected to stress, but the deformation of the inner strands 14 about the outer strands 15 is greater than the deformation of the inner strands 14 about the outer strands 16. The springiness of a net 18 having this design is firmer than in the exemplary embodiments described in the foregoing.
In a net 19 which is illustrated in FIG. 7, the distances between the outer strands 16 of the outer plane 13 are changed in such a way that, alternately, two of the outer strands 16 are disposed between two of the adjacent outer strands 15 of the outer plane 11, whereas the outer plane 13 does not have any outer strands 16 in the region between the following two outer strands 15 of the outer plane 11. The resilience of this net 19 varies in places, such that the springiness is firmer in those regions where the outer strands 16 are disposed between the outer strands 15.
In a net 20 which is illustrated in FIG. 8, the outer strands 15 and outer strands 16 also extend equidirectionally or parallel to one another, but they are located opposite one another in an essentially congruent manner, i.e. they are not offset in the longitudinal direction of the inner strands 14. This net 20 has only a small resilience, but it permits a constant and relatively great distance between the goods or articles which have to be spaced apart, even though the individual outer strands 15, 16 and inner strands 14 have a small diameter.
The outer strands 15, 16 and inner strands 14 of the illustrated nets 10, 17, 18, 19 and 20 preferably have circular cross sections of equal size. However, the cross section of the inner strands 14 may be greater or smaller than the cross section of the outer strands 15, 16 in order to vary the resilience. In this case the relation is such that, the greater the cross section of the inner strands 14, the firmer the springiness, and vice versa. The outer strands 15, 16 and/or inner strands 14 could also be provided with other cross sections (for example square, elliptic or other cross sections).
The nets 10, 17, 18, 19 and 20 have a tubular design. The tubular nettings 10, 17, 18, 19 and 20 are easy to pull over the goods which are to be protected or over the articles, especially plates, which have to be spaced apart. When the nets 10, 17, 18, 19 and 20 are used as protective nettings for highly finished surfaces, it is above all the three-layer design of the net which ensures a reliable protection of the goods against damage. The tubular nettings 10, 17, 18 and 19, whose thickness can be varied elastically, also offer a good padding for the goods which are enclosed in the net. When the tubular nettings 10, 17, 18, 19 are used as spacing means between heat storage plates of latent heat storage devices, the elastic resilience serves for compensating for the changes in the thickness of the heat storage plates caused by temperature variations. For this purpose, the nets 10, 17, 18 or 19 are compressed when the thickness of the heat storage plates increases.
Especially when the nets 10, 17, 18, and 19 are used as spacing means for heat storage plates, the mesh pattern of the outer strands 15 and 16 of the two outer planes 11, 13 is such that they always extend adjacent to the corners or edges of the heat storage plates. This ensures a secure and non-slip grip of the tubular nettings 10, 17, 18, or 19 on the heat storage plates. | Disclosed is a net (10), especially a spacing net, surface protection net or the like, in which the strands (14, 15, 16) are arranged in three planes (11, 12, 13), and in which the strands (15, 16) of two planes (11, 13) are oriented equidirectionally. As a result, a sufficient thickness of the net (10) can be ensured with a small cross section of the individual strands (14, 15, 16), which keeps the expenditure of material down to a minimum. Because the parallel strands (outer strands 15, 16) of the different outer planes (11, 13) are offset to one another in the direction of the inner strands (14), the intermediate strands (inner strands 14) can be deformed elastically, which results in very good padding properties and thickness variation properties of the net (10). | 8 |
[0001] This document is a request for a Patent of Invention for “IMPROVEMENTS IN BOXER PUPPETS AND REPRODUCTION OF BOXING MOVEMENTS”, particularly boxer puppets which include a series of movements ordered through commands mounted beside the ring and manually activated by two competitors, so that these referred puppets can apply various blows, using the arms, body and legs, creating a fighting situation very close to reality.
STATE OF TECHNIQUE
[0002] The present state of technique is composed of boxer puppets deposited by this inventor under no. PI 0100497-2, which analogously refers to the execution of fighting movements through commands activated by the competitors. In summary, there is a ring and, in two of its opposed vertices, commands for the right and left hands of each competitor, so that the corresponding boxer puppet moves by command of the respective competitor.
[0003] Although these boxer puppets have satisfactory efficiency, considering the state of technique, the inventor, searching for constant advance and improvement in the operational and manufacturing functions of the product, now requests important improvements put into effect in various devices of the boxer puppet. In general, the previous patent describes two boxer puppets, where each one has its own, identical and individual movement, manipulated by two players. It also affirms that they are fixed, one in front of the other on a square base, simulating a ring, having four controls, two for each boxer.
[0004] The previously mentioned patent document also affirms that the puppets oppose one another, launching a variety of blows, as in a conventional boxing match, even possibly causing a knockout. In this case, a blow of predetermined intensity on the head could activate a lock on the knee, causing the puppet which was hit to fall on its back; this mechanism can be reactivated.
[0005] The operation of the puppet, using the previous technique, was of an extremely complex construction, with an excessive number of parts, notably in reference to the body and arm movements, including helicoids springs. Besides this, the activators revealed an assembly of parts which had the purpose to pass, guide and move the activation cables; however, the movement and guiding system needed some modifications to offer greater durability, efficiency and a quick response from the various activators.
[0006] It should be noted that in the drawing of Figure C of the previous patent request, the puppet's body showed a cylinder to rotate it, besides the helicoid spring, interconnecting the arms and, last, a complex mechanism of couplings for the arms and cables to move the head.
THE INVENTION
[0007] The invention presented here has a series of improved constructive aspects, when compared to the previous technique. These characteristics extend to all sectors of the toy, that is, going from the activators, activation, rotation and cable guide mechanisms, as well as the mechanism to move the puppet's body, arms and head.
[0008] Technically, the improved boxer puppets use a shaft with a sphere inside the ring on each command mechanism, so that this sphere supports the fixed and rotating claws which transmit the movements to the various parts of the puppet through cables.
[0009] In each command mechanism mentioned there is a trigger through which a cable passes over the sphere and ascends inside the puppet, arriving at a crosspiece system which operates the puppet's arm movements, simplifying the response and making it more efficient, when compared to the mechanism of the previous technique.
[0010] Another aspect altered in the present invention consists in the head moving mechanism, which is designed to be moved when activating the respective cable which connects to a rod terminal.
[0011] The mechanism to move the puppet's body was also altered to gain more efficiency, durability and simplicity in construction, basically, a type of intermediary ring pivotally coupled to the puppet's lower members; this ring receives two terminals in diametrically opposed points, also pivotally coupled and projecting till a larger diameter ring, placed above them which, on its part, is topped by a relatively thin plastic sheet ( 34 ) projecting towards the puppet's head ( 35 ), where there are terminals ( 36 ), to receive the respective cables and over which covers are placed, forming the heads themselves ( 37 ).
[0012] The plastic sheet mentioned is composed of intermediate vertical slits, in which a transverse shaft is coupled, which projects from these slits beyond the sheet, where it is pivotally coupled, so that the cables coming from the activation trigger are fixed on the free ends of this shaft, as well as the shafts which extend to the right and left arms of the puppet, each one corresponding to its respective trigger. In summary, the invention stands out by proposing movements through activation controls, installed on the sides of the ring, diagonally opposite, two activators on each contrary sector, that is, one for the right hand and another for the left. In summary, each activating command mentioned performs four basic movements, so that each assembly, jointly, performs all the trunk, head, leg and arm movements of the puppets.
[0013] With the construction mentioned here, the boxer puppets can be manipulated with greater efficiency by the competitors, with quick responses, besides the fact that important innovations were added to the mechanism to move the trunk, head, arms and to move the feet.
DESCRIPTION OF THE DRAWINGS
[0014] The invention will be explained below, based on the drawings enclosed, which represent:
[0015] FIG. 1 : Perspective view showing a boxer puppet with feet and respective devices, as well as the activating commands;
[0016] FIG. 2 : Perspective view showing basically the same details of the previous figure, from another angle;
[0017] FIG. 3 : Perspective view showing basically the same details of the previous figures, with the boxer puppet seen from the back;
[0018] FIG. 4 : Perspective view showing basically the same details of the previous figures, with the boxer puppet seen from another angle;
[0019] FIG. 5 : Perspective view showing basically the same details of the previous figures, with the boxer puppet seen from the back;
[0020] FIG. 6 : Perspective view showing basically the same details of the previous figures, with the boxer puppet seen from the back and the body erect;
[0021] FIG. 7 : Perspective view showing basically the same details of the previous figures, with the boxer puppet seen from the back and the body slightly inclined;
[0022] FIG. 8 : This figure shows part of the ring, with some cables passing under it, to reach the boxer puppets, as well as the activating commands on one side of the ring;
[0023] FIG. 9 : This figure shows a boxer puppet with the devices of the right and left feet, seen from the side, with the activating commands;
[0024] FIG. 10 : This figure shows part of the ring, seen from the underside, with a boxer puppet on it, identifying the position of the support panels;
[0025] FIG. 11 : This figure shows the ring with the two boxer puppets, seen from above, also showing the activating commands;
[0026] FIG. 12 : This figure shows a partial and enlarged view of the boxer puppet's trunk;
[0027] FIG. 13 : This figure shows a partial and enlarged view of the boxer puppet's upper legs and lower trunk;
[0028] FIG. 14 : This figure shows a partial and enlarged view of the boxer puppet's upper trunk, part of the head and arms;
[0029] FIG. 15 : This figure shows a partial and enlarged view of the boxer puppet's head;
[0030] FIG. 16 : This figure shows a partial and enlarged view of the boxer puppet's upper legs from the back and the knee region;
[0031] FIG. 17 : This figure shows a partial and enlarged view of the boxer puppet's legs, from the side, especially the knee region, where it folds for a knockout.
DETAILED DESCRIPTION
[0032] The “IMPROVEMENTS IN BOXER PUPPETS AND REPRODUCTION OF BOXING MOVEMENTS”, the object of this request for Patent of Invention, consists in a toy, composed of boxer puppets ( 1 ), which are positioned on a small ring ( 2 ) and are monitored by two competitors by activating controls ( 3 ) disposed in pairs in two opposite points of the mentioned ring ( 1 ), preferentially on a diagonal.
[0033] The ring ( 2 ) is similar to a natural ring, that is, composed of a floor and side protection with ropes (or similar) distributed on the four sides. Each boxer puppet ( 1 ) mentioned is standing on the ring ( 2 ) floor, with the right foot ( 4 ) pivotally coupled to a specific mechanism, while the left foot ( 5 ) is also supported on a specific mechanism.
[0034] Each activating command ( 3 ) is composed by the activator itself ( 6 ) in the form of a handle (like a joystick), which is coupled on the bottom to a shaft ( 7 ) projecting inside the ring ( 2 ), passing concentrically to a guiding device ( 8 ) for the cables which will provide the actions. The shaft ( 7 ) is directly coupled to a cylindrical nucleus ( 9 ), but it is fixed to a seat ( 10 ) where a spherical joint ( 11 ) operates, enveloped by a ring ( 12 ), with ‘ears’ ( 13 ) for fixation. Just a bit ahead of the ring ( 12 ) there is a second cylindrical assembly ( 14 ), incorporating ‘ears’ ( 15 ) fixing it to the bottom, while a cable guide ( 16 ) is inserted near this second cylindrical assembly ( 14 ), while orifices ( 17 ) also serve as guides for the various cables.
[0035] After going through the orifices, already inside the ring ( 2 ), the cables meet on each side a group of support panels ( 18 ), each one equipped with a plurality of orifices ( 19 ) to direct the mentioned cables, one panel for each handle mentioned. To better understand the arrangement, the right support panel is numbered ( 18 D), while the left support panel is numbered ( 18 E) and these two alphabetical references also apply to the cables to be described in detail.
[0036] As to the body of each boxer puppet ( 1 ), it is formed by right ( 4 ) and left ( 5 ) feet and from each foot mentioned, there are plastic covers ( 20 ) projecting vertically, forming the puppet's legs; these covers ( 20 ) are pivoted near the feet through couplings ( 21 ) and also in the knee region, from where other covers ( 22 ) project forming the upper portion of the legs; these covers ( 22 ) end in an intermediate surrounding element ( 23 ) representing the genital and buttock regions of the puppet, where some cable passage guides ( 24 ) are concentrated. In the upper central region of this intermediate element ( 23 ) there is a connector ( 25 ) whose extremities form coupling pins for pivoting bearings ( 26 ) which incorporate a large diameter ring ( 27 ), on which the covers ( 28 ) which form the front and back parts of the puppet's ( 1 ) trunk are located.
[0037] The trunk includes a cable passage guide ( 29 ) fixed onto the mentioned cover, while two levers ( 30 ) for the arms are aligned with the passages of the cable guide mentioned ( 29 ), each one with a side ‘ear’ ( 31 ) having an orifice to receive the lower end of helicoid springs ( 32 ), whose upper ends are fixed to seats ( 33 ) incorporated to a relatively thin plastic sheet ( 34 ) projecting in the direction of the puppet's head ( 35 ), where there are terminals ( 36 ) to receive the respective cables and the covers which form the heads themselves ( 37 ). In this manner, the boxer puppet's ( 1 ) head will be movable to front and back with relative flexibility, notably the action of the head ( 35 ) in association with the helicoid springs ( 32 ).
[0038] The mentioned relatively thin plastic sheet ( 34 ) is composed of intermediate vertical slits ( 38 ), through which passes the cylindrical section ( 39 ) crosspiece which projects from these vertical slits beyond the sheet, where it pivots onto the levers ( 30 ), consequently activating the helicoid springs ( 32 ). On the free ends of this mentioned crosspiece ( 39 ) there are cylindrical sleeves ( 40 ) acting as seats for the cylindrical extremities ( 41 ) which incorporate equally cylindrical sleeves ( 42 ), with orthogonally positioned shafts in relation to the previous ones, which receive cable holder devices ( 43 ), besides helicoid springs ( 43 a ) which work to return the mentioned crosspiece ( 39 ) through a joint.
[0039] The covers ( 44 ) forming the arms are pivotally coupled onto this assembly described, which fit into seats ( 45 ) on the trunk covers, while the covers ( 46 ) forming the forearm are pivotally coupled onto those of the arms; these covers ( 46 ) incorporate the gloves ( 47 ).
[0040] The boxer puppet's ( 1 ) right foot ( 4 ) is arranged on the ring ( 2 ), particularly onto a vertical device ( 48 ), whose end forms a fixed sleeve ( 49 ) with the central shaft ( 50 ) providing a small movement for the right foot in relation to the central shaft ( 50 ), for they are united, while the mentioned vertical device is coupled onto a terminal base ( 51 ) on the side of which there is a small cylindrical tower ( 52 ), on whose diametrically opposed sector the terminals of a helicoid spring ( 53 ) are compressed, around the mentioned vertical device ( 48 ), so as to provide the right foot's return ( 4 ), whenever it rotates in translation, activated by the cable system. The left foot ( 5 ) is seated on a cylindrical device ( 54 ), in front of which a base ( 55 ) is conjugated, receiving a helicoid spring ( 56 ), with the function to always pull the left leg, folding it.
[0041] In the region of the right leg's knee, or immediately above it, the boxer puppet ( 1 ) has a knee disarming device, should the puppet receive a blow on the chin, simulating a knockout, that is, a locking element is foreseen, substantially in the form of an “L” ( 57 ), articulated onto the shaft ( 58 ); one of the ends of this locking element ( 57 ), forms a point ( 59 ) to be normally retained by the tooth ( 60 ) foreseen on the lower right leg cover, while the other end of the “L” mentioned receives a cable holder ( 61 ); a flexible side extension ( 62 ) with teeth, acts as a pressure element and locks the boxer puppet ( 1 ) in the armed position.
[0042] The activation controls ( 3 ) are divided into right command ( 3 D) and left command ( 3 E); the right command ( 3 D) receives the right cables ( 1 D), ( 2 D), ( 4 D), ( 5 D) and ( 7 D), which, after passing by the mentioned right command ( 3 D) project inside the ring ( 2 ), go through the right support panel ( 18 D) and extend till the respective holders.
[0043] In relation to the left command ( 3 E) it receives the left cables ( 1 E), ( 2 E) ( 3 E), ( 4 E), ( 5 E), which then go through the mentioned left command ( 3 E) and project inside the ring ( 2 ), pass through the left support panel ( 18 E) and extend till the respective holders.
[0044] Cable ( 3 E) extends till the left foot of the boxer puppet ( 1 ), where it couples under the mentioned left foot, so that, when activated by the left handle ( 6 ) in the direction to pull cable ( 3 E), the left leg will move backward (stretching it), that is, it leaves the left leg in an extended position, returning to normal when the knee inclines toward the front by action of the helicoid spring ( 56 ), which has the function to pull the leg and fold it. On the other hand, moving the left handle ( 6 ) sidewards, causes the right foot to rotate and, consequently, the right leg. These movements are better explained in the section where the movements are described.
[0045] Thus, the cables mentioned are projected inside the boxer puppet ( 1 ); cables ( 1 E) and ( 2 E), activated by the left handle, extend till the cylindrical terminals ( 30 ), directly acting on the crosspiece ( 39 ), so that these cables are responsible for raising (rotating) the arms, through the lever effect caused by the mentioned crosspiece ( 39 ).
[0046] The right and left forearms ( 46 ), respectively, receive cables ( 4 D) and ( 4 E), each one responsible for activating the correspondent forearm ( 46 ) when a left or right punch is provoked.
[0047] In relation to the trunk or thorax of the boxer puppet ( 1 ), it can be moved forward and to the sides. For this, cables ( 5 D), ( 6 D) and ( 7 D) act on ring ( 27 ) to move the thorax forward and to the sides, while cables ( 1 D) and ( 2 D) are applied to the cover immediately above ring ( 27 ), so that, responding to the user's command, it allows the thorax to move to the left or right, by the rotating shaft ( 27 a ).
[0048] A stretcher ( 63 ) projects from the back of the boxer puppet's head ( 1 ), till the ring region ( 27 ) to maintain the head looking towards the front while the thorax moves, simulating the posture of an athlete practicing this sport.
[0049] On the other hand, two side stretchers ( 64 ) project from the upper portion of the internal structure of the puppet's head, which go through the ring ( 27 ) and extend till the intermediary element ( 23 ), to maintain the head aligned sideways while the thorax moves.
[0050] On the back and upper parts of the head, there is a cable holder ( 65 ) from where cable ( 66 ) is extended till holder ( 61 ), that is, it is a wire or cable ( 65 ) connecting the lever ( 67 ) of the chin and the lock ( 57 ) of the right leg. Thus, when the puppet receives a punch on the chin, the wire or cable ( 65 ) activates the lock ( 57 ) mentioned on the right leg, liberating its folding, causing the boxer to fall, simulating a knockout. To rearm the right leg and continue the fight, one must only bring the right leg forward, for the lock ( 57 ) to place it again in position. In reality, boxer puppet ( 1 ) can perform, in essence, four movements, activated by the right and left commands ( 3 ). Let us see the movements made by the right activating command:
[0051] Movement 1 (D): trunk rotation is performed starting by rotating the activator itself ( 6 ), as described;
[0052] Movement 2 (D): moving the activator itself ( 6 ) up makes the trunk incline forward, and returning the activator automatically makes the trunk return, as described;
[0053] Movement 3 (D): moving the activator itself ( 6 ) sideways (without rotating it), makes the boxer puppet's ( 1 ) waist move right or left, as described;
[0054] Movement 4 (D): the activator itself ( 6 ) has a trigger (G) (like a joystick) which, on being moved, sends the right arm forward, as described, and releasing the trigger, the arm returns.
[0055] Let us see the movements made by the left activator:
[0056] Movement 1 (E): rotating the left activator itself ( 6 ) to the right and left, makes the corresponding arm move up and down, in quick movements, as described;
[0057] Movement 2 (E): taking the activator itself ( 6 ) down, the left leg remains extended; on returning to normal, the knee inclines lightly forward, as described;
[0058] Movement 3 (E): by moving the activator itself ( 6 ) sideways, the right foot ( 4 ) rotates (consequently the right leg), from a small movement of the heel, besides causing an angular movement of the body, keeping the left foot ( 5 ) (consequently the left leg) fixed;
[0059] Movement 4 (E): the same movement 4 (D), for the left arm. | “IMPROVEMENTS IN BOXER PUPPETS AND REPRODUCTION OF BOXING MOVEMENTS”, particularly of boxer puppets which include a series of movements ordered through commands mounted beside the ring and manually activated by two competitors, so that these referred puppets can provoke various blows, including with the arms, body and legs, creating a fighting situation very close to reality. Composed of boxer puppets ( 1 ), which are positioned on a small ring ( 2 ) and are monitored by two competitors through the activation of controls ( 3 ) disposed in pairs, in two opposite points of the mentioned ring ( 1 ), preferentially on a diagonal; each mentioned boxer puppet ( 1 ) is positioned standing on the ring ( 2 ), having the right foot ( 4 ) pivotally coupled to a mechanism; the same occurs with the left foot ( 5 ); the boxer puppet ( 1 ) has characteristics of movement for the legs, trunk, arms and head. | 0 |
BACKGROUND OF THE INVENTION
Metal panels provide good roofs, but cannot be applied as large sections of a roof due to temperature related buckling, distribution of fasteners, and wind-lift issues. Many attempts to use large-area metal panels have failed for these reasons. Long narrow roof panels, however, have proven successful. A roof structure results by placing a series of elongate narrow panels side-by-side in overlapping and interlocking relation across a roof substrate.
Thus, metal roof panels are from one to one and one-half feet wide and extend vertically along the roof from gutter line to ridge. The depth of panels is typically one to three inches as provided by bending formations for rigidity and by interlocking structures. Each panel has complimentary interlocking structures along its edges. A left edge of a first panel interlocks with an overlapping right edge of a second adjacent panel. A variety of particular configurations and interlocking structures have developed, but the basic method of use is by complimentary interlocking structures along the edges of each elongate roof panel.
In a typical configuration, each panel includes a female structure and a complimentary male structure along respective edges of the elongate panel. At the outermost edge and adjacent the female structure, a series of apertures allow attachment by fasteners therethrough to a roof substrate. This ties-down the "female" side of each panel. The male structure of an adjacent second panel couples, i.e., interlocks by virtue of the complimentary relation to the female structure, to the female structure of the previous panel in the series. This ties-down the "male" side of each panel. Each panel at its "male" side covers the fasteners along the "female" side of the previous panel in the series. Thus, while each panel attaches directly to the roof substrate only at one edge, the other edge interlocks to a previous panel along the fastened edge of that previous panel.
In applying such roofing panels, a worker lays down at one extreme edge of the roof, e.g., the left-most edge, a roof panel and screws it in place including attachment along its right edge. The next panel then lays upon and interlocks at its left edge with the right edge of the first panel. One person works a given planar roof section at a time because, at any given time, there is only one "working edge" available to receive a next panel in the series of panels. The process continues in series until a given section of roof is traversed sideways, e.g., left to right.
A particular problem arises in hip roof applications. More particularly, a hip roof includes four or more planar regions. For each planar region, the outside portions taper in length, i.e., progressively shorter distance between ridge line and gutter line as one approaches the outer-most edges. In applying the metal roof panels as described above, one begins at the left-most edge of a given planar section and works across the roof section. The first panel attached is the shortest panel of the series of panels for that section of roof. One must carefully align this first and very short roof panel as this first panel sets the orientation, i.e., vertical alignment, for all remaining panels across this section of roof. Despite best efforts, many panels are not properly aligned due to small errors at the beginning of the process, i.e., the initial short length panel was crooked, and such errors propagate across the entire planar roof section. Sometimes this results in an unacceptable appearance and requires removal and re-application of roof panels. Such removal often results in damage or sometimes destruction of the roof panels. Furthermore, such removal constitutes unproductive roof construction necessitated by the occasional need to remove panels due to misalignment.
In any construction project, time is of the essence. The faster a job can be completed the more valuable the job is to the customer and to the contractor providing the job. Due to the quality issues and productivity issues presented in constructing metal roofs by means of conventional, elongate, narrow roof panels, it would be desirable to improve metal roof construction in both quality and productivity.
SUMMARY OF THE INVENTION
The subject matter of the present invention concerns improvement in not only roof quality but also productivity in connection with constructing roofs with metal roof panels. The present invention contemplates at least one "center" panel mounted in a central portion of a given planar roof section. This center panel has matching, e.g., both female or both male, interlocking structures along its left and right edges. The center panel thereby presents two "working edges." A first series of conventional panels extend leftward and a second series of conventional panels extend rightward. A first person works rightward from the right edge of the center panel and a second person works leftward from the left edge of the center panel. Both workers apply "conventional" metal roof panels laterally outward to complete each sub-portion of the planar roof section. This immediately doubles productivity because two workers apply panels to a given roof section at one time. The center panel, often the longest panel in a given planar section of roof, can be better aligned and provide greater opportunity to align all roof panels in a given roof section. This reduces the possibility of having to remove mis-aligned roof panels during construction.
The subject matter of the present invention is particularly pointed out and distinctly claimed in the concluding portion of this specification. However, both the organization and method of operation of the invention, together with further advantages and objects thereof, may best be understood by reference to the following description taken with the accompanying drawings wherein like reference characters refer to like elements.
BRIEF DESCRIPTION OF THE DRAWINGS
For a better understanding of the invention, and to show how the same may be carried into effect, reference will now be made, by way of example, to the accompanying drawings in which:
FIG. 1 illustrates schematically a building structure including a hip roof and roof system according to a preferred embodiment of the present invention.
FIG. 2 illustrates the building structure and roof system of FIG. 1 as taken along lines 2--2 of FIG. 1.
FIG. 3 illustrates a roof panel including complimentary interlocking structures at both sides of the panel.
FIG. 4 illustrates a center panel according to the present invention and including matching interlocking structures along both edges of the panel.
FIG. 5 illustrates an end view of a centering panel as illustrated in FIG. 4 and a series of conventional panels as illustrated in FIG. 3 extending laterally rightward and leftward therefrom to establish a roof system according to a preferred embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
With reference to FIGS. 1 and 2, a roof system 10 according to a preferred embodiment of the present invention makes use of at least one center panel 12 in each planar section of the roof system 10. FIGS. 1 and 2 illustrate, as an example, application of the present invention to a hip roof architecture. The hip roof architecture illustrated defines four planar sections 14, individually 14a-14d. Each planar section 14 has as its lower-most edge a gutter line 16, individually gutter lines 16a-16d. An upper ridge line 18 corresponds to the intersection between sections 14a and 14c. Similarly, ridge line 20 lies at the intersection of sections 14c and 14d; ridge line 22 at the intersection of sections 14d and 14a; ridge line 24 at the intersection of sections 14a and 14b; and ridge line 25 at the intersection of sections 14b and 14c.
For each planar roof section 14, at least one center panel 12 is placed first at a lateral midpoint in the section 14 and extending upward from the gutter line 16. For example, in section 14a, center panel 12a extends from gutter line 16a upward to ridge line 18. In section 14b, center panel 12 extends from gutter line 16b upward to the intersection of ridge lines 18, 24, and 25. In each case, the center panel 12 is best placed in a central position from left to right and as the longest roofing panel in that planar section 14. Center panels 12c and 12d are similarly first placed in sections 14c and 14d, respectively.
A series of conventional panels 30 extend laterally outward from each centering panel 12 to complete coverage of a given planar section 14. FIG. 3 illustrates in perspective a conventional panel 30 and FIG. 4 illustrates in perspective a center panel 12.
In FIG. 3, a conventional panel 30 includes complimentary interlocking structures 40 and 42. In this regard, complimentary refers to an ability of one structure's shape to couple or lock to the other structure's shape. For example, conventional panel 30 includes a male interlocking structure 40 along its left edge (as viewed in FIG. 3) and a female interlocking structure 42 along its right edge (as viewed in FIG. 3). In this particular arrangement, male interlocking structure 40 presents an inward-facing shelf 40a and a tunnel structure 40b. Shelf 40a extends to the leftmost edge of panel 30. Female interlocking structure 42 includes a shelf 42a and a tunnel 42b. The rightmost edge of conventional panel 30 includes a planar shelf 46 and therealong apertures 48. A series of conventional panels 30 attach to a roof substrate in conventional fashion by attaching a given panel 30 by fasteners through apertures 48 and then placing the tunnel structure 40b of a next panel 30 over the tunnel structure 42b of the previously attached panel 30.
In FIG. 4, center panel 12 differs from conventional panels 30 in that it has matching interlocking structures along both edges. In the particular example illustrated herein, a center panel 12 includes at its right edge and left edge a female interlocking structure 42 including a shelf 42a and a tunnel 42b as are present on conventional panels 30. Center panel 12 also includes a planar shelf 46 and apertures 48 along both edges for attachment to a roof substrate.
Conventional panels 30 may be flipped end-for-end without any change in function or appearance so long as a given series of panels 30 have the same orientation. In FIG. 3, conventional panel 30 is in a first orientation with its male interlocking structure 40 on the left side and female interlocking structure 42 on the right side in the view of FIG. 3. Flipping conventional panel 30 end-to-end relative to that illustrated in FIG. 3, presents at the right edge of conventional panel 30 the male interlocking structure 40 and at the left edge of conventional panel 30 the female interlocking structure 42. With a center panel 12 presenting on each edge a female interlocking structure 42, conventional panels 30 extending in series rightward therefrom each have on their left side a male interlocking structure 40. Conventional panels 30 extending in series leftward from a center panel 12 each have on their right side a male interlocking structure 40.
FIG. 5 illustrates one possible sequence of construction contemplated under the present invention beginning with a center panel 12 attached, at a mid-portion of a planar roof section 14, along its left and right edges by placement of fasteners 70 through apertures 48 (not shown in FIG. 5). This ties down the center panel 12 at both edges to the roof substrate. A first series 80 of conventional panels 30 have a first orientation presenting at their left edge a male formation 40 and at their right edge a female formation 42. Once center panel 12 is fastened as described above, a first conventional panel 30 of series 80 may be attached to center panel 12 by engaging its male interlocking structure 40 with the female interlocking structure at the right edge of center panel 12. The rightmost edge of this first conventional panel 30 in series 80 may then be attached to the roof substrate by means of fasteners 70. Successive additional conventional panels 30 are then incorporated into series 80 by attaching a male interlocking structure 40 at each left edge thereof with a female interlocking structure 42 at a rightmost edge of a previously fastened conventional panel 30.
A second series 82 of conventional panels 30 may be attached to the roof concurrent with the process of attaching series 80. Conventional panel 30 members of series 82, however, have an opposite orientation, i.e., are flipped end-to-end relative to the orientation of conventional panels 30 of series 80. Accordingly, each conventional panel 30 of series 82 presents at its right edge a male interlocking structure 40 and at its left edge a female interlocking structure 42. A first conventional panel 30 in series 82 connects to center panel 12 by engaging its male interlocking structure 40 with the left female interlocking structure 42 of center panel 12. The left edge of this first conventional panel 30 of series 82 is then attached by fasteners 70 to the roof substrate. Successive members of series 82 are then attached to the roof substrate in series and in conventional fashion.
Because center panel 12 can be of maximum length for a given planar section, the overall pattern of conventional panels 30 resulting has a greater chance of being straight and uniform. In contrast, conventional methods of metal roof construction contemplate beginning with a short panel section at an extreme edge of the planar roof section and minor alignment errors propagate throughout the pattern often resulting in an undesirable appearance or need to replace due to initial, almost unavoidable in many cases, alignment errors.
Generally, each planar section includes at least one centering panel allowing construction laterally outward therefrom. It is possible under the present invention to begin with more than one centering panel to establish more than two "working edges", however, this would require accurate measurement to coordinate the positioning of panels as they approach a previously-installed panel. The preferred method is to place one centering panel in a given planar area and work outward in two directions therefrom. At minimum, this doubles productivity and also increases dramatically the chances of establishing a well aligned roof panel pattern.
It will be appreciated that the present invention is not restricted to the particular embodiment that has been described and illustrated, and that variations may be made therein without departing from the scope of the invention as found in the appended claims and equivalents thereof. | Elongate metal roof panels with interlocking edge formations combine to establish a roof system. A center panel having matching edge locking formations and positioned at a mid-point on a planar roof section couples to a first series of elongate metal roof panels extending leftward and couples to a second series of elongate metal roof panels extending laterally rightward. Members of the first and second series of panels are similar in structure and include complimentary locking edge structures, but couple in opposite orientation. | 4 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a rotational driving apparatus and a camera using the rotational driving apparatus, and more particularly to a rotational driving apparatus to be used as a rotational driving source for a lens device in which a lens is moved forward and backward along the optical axis by a cam mechanism, and a camera using the rotational driving apparatus.
[0003] 2. Description of the Related Art
[0004] In the case where rotation of a motor is to be decelerated at once, for example, a worm gear is usually used. A worm gear consists of a worm and a worm wheel. In the case where rotation of a motor is to be decelerated at once, a worm is previously attached to an output shaft of the motor, and rotation of the motor is transmitted to a worm wheel which meshes with the worm, thereby immediately decelerating the rotation.
[0005] Usually, a worm is attached to an output shaft of the motor by press fitting. There is a possibility that the press fitting is loosened as a result of a long term use and the worm moves on the output shaft to slip off from the output shaft.
[0006] In JP-A-2001-309610, therefore, the tip end of a worm which is press fitted to an output shaft of a motor is pressed by a pressing member such as a spring, thereby preventing the worm from slipping off.
[0007] In the worm supporting structure disclosed in JP-A-2001-309610, however, the pressing force which is applied to the worm by the pressing member cannot be adjusted, and hence there is a drawback that, when the components have a dimensional error, an adequate pressing force cannot be applied to the worm. As a result, the structure has drawbacks that an excessive pressing force is applied to the worm to produce a friction loss, and that, when the pressing force is insufficient, backlash occurs in the worm.
SUMMARY OF THE INVENTION
[0008] The invention has been conducted in view of such circumstances. It is an object of the invention to provide a rotational driving apparatus which can stably perform a driving operation, and a camera using the rotational driving apparatus.
[0009] (1) In order to attain the object, the invention provides a rotational driving apparatus which comprises a motor, a worm that is pressingly fitted to an output shaft of the motor, and a worm wheel that meshes with the worm, so as to output rotation of the motor from the worm wheel via the worm, wherein the rotational driving apparatus comprises: a support member that is placed with forming a gap with respect to a tip end of the worm, the support member comprising a through hole positioned on a same axis as the worm; a pressing member that is inserted into the through hole, and protrudes from a tip end of the through hole to butt against a tip end face of the worm; a plug member that is fitted into the through hole to close the through hole, and in which a degree of a fitting of the plug member into the through hole is adjustable; and an urging member that is interposed between the pressing member and the plug member to urge the pressing member toward the worm.
[0010] According to the invention, the tip end face of the worm is axially pressed by the pressing member which is urged by the urging member. In the urging member which urges the pressing member, the urging force can be adjusted by changing the degree of the fitting of the plug member. Therefore, an adequate pressing force can be applied to the worm.
[0011] (2) In order to attain the object, the invention provides a rotational driving apparatus wherein, in the apparatus of (1), the pressing member is formed into a spherical shape.
[0012] According to the invention, the pressing member is formed into a spherical shape. As a result, the pressing member makes point contact with the tip end face of the worm, and hence the friction loss can be suppressed to a minimum level.
[0013] (3) In order to attain the object, the invention provides a rotational driving apparatus wherein, in the apparatus of (1) or (2), the plug member is a male thread which is screwed with a female thread portion formed in an inner periphery of the through hole.
[0014] According to the invention, the plug member is configured by a male thread, and the degree of the fitting into the through hole is adjusted by changing the fastening position or the thread length.
[0015] (4) In order to attain the object, the invention provides a rotational driving apparatus wherein, in the apparatus of (2) or (3), the tip end face of the worm comprises a recess having a hemispherical shape.
[0016] According to the invention, the tip end face of the worm comprises a recess having a hemispherical shape. Therefore, the pressing member which has a spherical shape can be always caused to butt against the center of the worm, and hence a stable pressing force can be applied without causing eccentricity.
[0017] (5) In order to attain the object, the invention provides a lens; and a cam mechanism that operates by receiving a rotational driving force from a rotational driving apparatus of (1), (2), (3), or (4), wherein the lens is moved forward and backward along an optical axis by the cam mechanism.
[0018] According to the invention, the rotational driving apparatus of (1), (2), (3), or (4) is used as a rotational driving source for the lens device in which a lens is moved forward and backward along the optical axis by a cam mechanism. In a lens device in which a lens is moved by a cam mechanism, the operating power is changed at the inflection point of a cam. When the rotational driving apparatus of (1), (2), (3), or (4) is used as a rotational driving source, however, abnormal noises and vibrations are suppressed, so that stable driving is enabled.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] FIG. 1 is a perspective view showing the external configuration of a camera using the rotational driving apparatus of the invention;
[0020] FIG. 2 is a view schematically showing the configuration of a zoom driving portion for an imaging lens;
[0021] FIG. 3 is a view showing the configuration of a worm supporting mechanism;
[0022] FIG. 4 is a view showing another embodiment of the worm supporting mechanism; and
[0023] FIG. 5 is a view showing a further embodiment of the worm supporting mechanism.
DETAILED DESCRIPTION OF THE INVENTION
[0024] Hereinafter, the best mode for carrying out the rotational driving apparatus of the invention, and a camera using the rotational driving apparatus will be described in detail with reference to the accompanying drawings.
[0025] FIG. 1 is a perspective view showing the external configuration of a camera using the rotational driving apparatus of the invention. The camera 10 is a film camera which uses a 135 film. An imaging lens 14 , a finder window 16 , a strobe flash 18 , and the like are disposed on the front face of the camera body 12 . A shutter release button 20 is disposed on the upper face of the camera body 12 , and a power switch, a zoom button, and the like are disposed on the back face of the camera body 12 which is not shown.
[0026] The imaging lens 14 is configured by a collapsible type zoom lens. When the power supply of the camera 10 is turned ON, the lens advances from the front face of the camera body 12 , and then stops at the wide-angle end. When the power supply of the camera 10 is turned OFF, the lens is housed in the camera body 12 . When the zoom button is operated, the imaging lens 14 protruding from the camera body 12 is zoom-driven so that the focal length is changed.
[0027] FIG. 2 is a view schematically showing the configuration of the zoom driving portion for the imaging lens 14 . In the imaging lens 14 , when an operating gear 24 formed on the outer periphery of a lens barrel 22 is rotated, the lens barrel 22 is caused to extend or contract along the optical axis by the function of a cam mechanism which is not shown, whereby the focal length is changed. The operating gear 24 is rotated by a zoom motor 26 .
[0028] The zoom motor 26 is fixed to a camera body frame which is not shown. A worm 28 is attached to an output shaft 26 A of the motor. A worm wheel 30 meshes with the worm 28 , and rotation of the zoom motor 26 is transmitted from the worm wheel 30 to the operating gear 24 via a reduction gear train 32 .
[0029] The worm 28 is formed into a hollow shape, and attached to the output shaft 26 A of the zoom motor 26 by pressingly fitting the output shaft 26 A into the hollow portion.
[0030] The worm wheel 30 is rotatably supported by a shaft 34 formed on the camera body frame which is not shown. A small-diameter output gear 36 is formed coaxially with the upper face of the worm wheel 30 in an integral manner.
[0031] The reduction gear train 32 is configured by first to sixth gears 32 A to 32 F. The first gear 32 A is rotatably supported by a shaft 40 formed on the camera body frame which is not shown, and meshes with the output gear 36 . The second gear 32 B having a small diameter is formed coaxially with the lower face of the first gear 32 A in an integral manner.
[0032] The third gear 32 C is rotatably supported by a shaft 42 formed on the camera body frame which is not shown, and meshes with the second gear 32 B. The fourth gear 32 D having a small diameter is formed coaxially with the upper face of the third gear 32 C in an integral manner.
[0033] The fifth gear 32 E is rotatably supported by a shaft 44 formed on the camera body frame which is not shown, and meshes with the fourth gear 32 D.
[0034] The sixth gear 32 F is rotatably supported by a shaft 46 formed on the camera body frame which is not shown, and meshes with the fifth gear 32 E, and also with the operating gear 24 .
[0035] Rotation of the output shaft 26 A of the zoom motor 26 is transmitted from the worm 28 to the worm wheel 30 , and then from the worm wheel 30 to the operating gear 24 via the reduction gear train 32 , whereby the imaging lens 14 is driven.
[0036] As described above, the attachment of the worm 28 to the output shaft 26 A of the zoom motor 26 is realized by press fitting onto the output shaft 26 A. Consequently, there is a possibility that the fitting is loosened as a result of a long term use and the worm slips off from the output shaft 26 A. In order to prevent the worm 28 from being loosened, a worm supporting mechanism 50 which axially presses the worm 28 to support it is disposed in a tip end portion of the worm 28 .
[0037] FIG. 3 is a view showing the configuration of the worm supporting mechanism 50 . As shown in the figure, the worm supporting mechanism 50 is configured by a worm supporting mechanism body 52 , a rigid ball 54 , a screw 56 , and a coil spring 58 .
[0038] The worm supporting mechanism body 52 is formed into a block-like shape, and placed with forming a predetermined gap with respect to the tip end face of the worm 28 which is press fitted onto the output shaft 26 A. The worm supporting mechanism body 52 is fixed to the camera body frame which is not shown. A through hole 60 is formed in the body so as to be coaxial with the worm 28 .
[0039] The rigid ball 54 is inserted into the through hole 60 formed in the worm supporting mechanism body 52 , and protrudes from the tip end face of the through hole 60 to butt against the tip end face of the worm 28 .
[0040] A female thread portion 60 A is formed in the inner periphery of a basal end portion of the through hole 60 . The screw 56 is screwed with the female thread portion 60 A of the through hole 60 .
[0041] The coil spring 58 is interposed between the rigid ball 54 and the screw 56 . The rigid ball 54 is urged by the coil spring 58 to axially press the tip end face of the worm 28 .
[0042] When the screw 56 is deeply fastened to the female thread portion 60 A, the coil spring 58 exerts a large urging force, and, when the screw 56 is shallowly fastened, the coil spring 58 exerts a small urging force. Namely, the degree of the urging force exerted by the coil spring 58 can be adjusted in accordance with the fastening position of the screw 56 . As a result, it is possible to adjust the pressing force exerted by the rigid ball 54 .
[0043] In the thus configured zoom driving portion for the imaging lens 14 of the camera 10 of the embodiment, when the zoom motor 26 is driven to rotate the output shaft 26 A, the rotation of the output shaft 26 A is transmitted from the worm 28 to the worm wheel 30 , and then from the worm wheel 30 to the operating gear 24 via the reduction gear train 32 . As a result, the imaging lens 14 is driven, and the lens barrel 22 is caused to extend or contract along the optical axis by the function of the cam mechanism which is not shown, whereby the focal length is changed.
[0044] In this case, the worm 28 is always axially pressed by the rigid ball 54 of the worm supporting mechanism 50 , and hence is not loosened, so that stable rotation can be always ensured.
[0045] The degree of the pressing force which is applied form the rigid ball 54 to the worm 28 can be adjusted by the fastening position of the screw 56 . Even when the accuracies of the components are dispersed, therefore, a pressing force which is optimum for each product can be always applied, and stable operation can be ensured.
[0046] Since the component which presses the tip end face of the worm 28 is the rigid ball 54 , the rigid ball 54 makes point contact with the worm 28 . Therefore, the friction loss can be suppressed to a minimum level, so that the driving operation can be efficiently performed.
[0047] In the embodiment, the component which presses the tip end face of the worm 28 is the rigid ball 54 . However, the component which presses the tip end face of the worm 28 is not restricted to this. When a friction loss is considered, however, it is preferable to employ a configuration where the member makes point contact with the tip end face of the worm 28 as in the embodiment. As shown in FIG. 4 , for example, a pressing member 55 in which a tip end portion has a conical shape may press the tip end face of the worm 28 .
[0048] In the case where the component which presses the tip end face of the worm 28 is the rigid ball 54 , the tip end face 28 A of the worm 28 may be formed into a hemispherical shape as shown in FIG. 5 . According to the configuration, the rigid ball 54 is always caused to press the center of the worm 28 by the centripetal action of the tip end face, whereby stable rotation of the worm 28 can be always ensured.
[0049] In the embodiment, the screw 56 is used as the plug member which closes the basal end portion of the through hole 60 formed in the worm supporting mechanism body 52 . The plug member is requested only to have a configuration in which the degree of fitting (fitting depth) into the through hole 60 is adjustable, and is not restricted to the screw 56 .
[0050] In the embodiment, the degree of fitting into the through hole 60 is adjusted by the fastening position of the screw 56 . Alternatively, the degree of fitting into the through hole 60 may be adjusted by using screws of different lengths.
[0051] In the above, the embodiment in which the invention is applied to a zoom driving portion of a camera has been exemplarily described. The application of the invention is not restricted to this, and the invention can be similarly applied to other machines.
[0052] In the rotational driving apparatus of the invention, and a camera using the rotational driving apparatus, it is possible to stably perform a driving operation.
[0053] The entire disclosure of each and every foreign patent application from which the benefit of foreign priority has been claimed in the present application is incorporated herein by reference, as if fully set forth. | A rotational driving apparatus which comprises a motor, a worm pressingly fitted to an output shaft of the motor, and a worm wheel meshing with the worm, to output rotation of the motor from the worm wheel via the worm, the apparatus comprising: a support member placed with forming a gap with respect to a tip end of the worm, the support member comprising a through hole positioned on a same axis as the worm; a pressing member that is inserted into the through hole, and protrudes from a tip end of the through hole to butt against a tip end face of the worm; a plug member fitted into the through hole to close the through hole, in which its fitting degree into the through hole is adjustable; and an urging member interposed between the pressing member and the plug member to urge the pressing member toward the worm. | 6 |
FIELD OF THE INVENTION
The present invention relates generally to the field of clocks and timers. More specifically, the present invention relates to a timing device disposed within a projector or within presentation software that aids a presenter and/or audiovisual personnel in tracking the elapsed time of a presentation.
BACKGROUND OF THE INVENTION
There are many conventional devices used for displaying information to an audience. Examples of an audience may include a group of students seated in a classroom, a group of business people at a conference, and participants connected to a conference via video conferencing equipment. Information presented to the students and other audiences, perhaps by a professor or a guest speaker, may be presented using a projector, such as an overhead projector or a slide projector. Information presented to an audience may also be presented using a personal computer, such as a laptop computer connected to a display projection device.
Conventional timing devices, such as clocks and stopwatches, are well known. In a typical classroom environment, there is typically a clock located on one of the classroom walls that displays the time of day. However, the clock typically does not possess stopwatch-type functions, and may not be in the same line of sight as the projector screen, making it inconvenient to look at the clock while maintaining focus on the subject matter of the presentation. Also, a presenter is not able to control the timing functions of a wall clock. There may be occasions during a presentation when it would be desirable for a speaker to have control of timing functions, such as during an experiment, an exam, or in tracking the total elapsed time of a presentation.
Video conferencing is typically a costly service. Displaying a timer to each conference participant would aid in the tracking of the total time of the video conference so as to make participants aware of the cost of the conference. Displaying the elapsed time of a video conference to all participants also aids in reminding the participants of how long they have been involved in a conference, in case they have a schedule to maintain. Since participants may become very involved in a conference and may lose track of the time, displaying the time to each participant on their individual screen is an effective way of providing a constant reminder.
A conventional time tracking approach is provided in U.S. Pat. No. 5,590,944, in which a portable electronic device having a transparent liquid crystal display is described. The timing device includes a plastic casing, foldable legs, and is placed onto the surface of a projector where light passes through the device and displays LCD numerals onto a screen. A disadvantage of the timer of the '944 patent is that it is not connected to a projector and may be easily lost, separated, or dropped from the projector surface. Since the device of the '944 patent is not integrated into the projector, it must also be supplied as a separate piece of equipment. Another disadvantage of the '944 timer is that it must be placed onto a flat, horizontal surface, such as that of an overhead projector. Many conventional projectors, such as a slide projector, do not possess a flat horizontal surface, making the conventional timer of the '944 patent impossible to use. An additional disadvantage of the '944 timer is that it interferes with the working space of an overhead projector surface, making it troublesome for a presenter to switch transparencies on the overhead projector without knocking the '944 timer out of place or even off of the projector surface onto the floor, where it may be become damaged.
A second timer approach is provided in U.S. Pat. No. 5,905,694, in which a timing device for coordinating a presentation includes a master timer with a timing initiator, a programmable master sensory alarm responsive to the sequencer, a master alarm silencer, and a communication transmitter responsive to at least one of the timing initiator and the master sequencer. The device of the '694 patent involves a low power radio signal transmitted by the communication transmitter. The timing device of the '694 patent is used for coordinating the timing of a presentation, but does not include a time display that may be displayed to the audience. The device involves sending a signal from a master controller to a slave timer that alerts a speaker of a time limit.
It is further desirable to have a device that allows a presenter of an audio/visual presentation to track the elapsed time of a presentation. It is also desirable to provide a time tracking device in which the presenter can start, stop, and pause the time tracking device in a simple manner, without taking time away from a presentation. Preferably, such a device would be included within a projector device, thus eliminating the need for a presenter to supply such a device for a presentation. It is also preferable that the time displayed on the timing device be capable of being projected by a projector to the viewing audience in an easy to read and interference free manner.
SUMMARY OF THE INVENTION
In one embodiment, the present invention provides a time tracking device disposed within a projector for the purpose of tracking presentation time and displaying the presentation time to an audience. The time tracking device may be disposed within any type of projector device, examples of which may include an overhead projector, as is often used in an educational classroom environment, a slide projector, a projector operably connected to a laptop computer, or any other type of projector device. The time tracking device may include features such as start, stop, pause, reset, etc. The present invention solves the problems associated with the conventional time tracking devices described above by providing a time tracking device that is incorporated into the projector housing, eliminating the need for a time tracking device to be supplied by a presenter. The device of the present invention may be operated by a presenter and/or by audiovisual personnel. The present invention also provides an easy to use device that does not interfere with the use of its associated projector.
The time tracking device of the present invention may include keys operable for controlling the functions of the device, such as a start key, a stop key, a reset key, a pause key, an on/off key, a display key, a mode key, or any other additional key that may be assigned a specific function. The time tracking device further includes a timer display, either analog or digital, that may be displayed to an audience via the projector light source and projector lens. In an alternative embodiment, the display may be displayed only to the presenter. The time tracking device display may include a liquid crystal display or any other type of display capable of being projected onto a screen viewed by the audience.
In a further embodiment, the time tracking device may be incorporated into the presentation hardware of a projector. In one example, the functions of the time tracking module may be controlled using the remote control unit associated with a projector device.
The time tracking device of the present invention eliminates the need for a presenter to supply his/her own time tracking device.
The time tracking device has a low power requirement which may be satisfied by solar panels, a battery, a connection to the circuitry of the associated projector, or a combination of any of the preceding.
Additional objects, advantages, and novel features of the invention will be set forth in part in the description which follows, and in part will become more apparent to those skilled in the art upon examination of the following, or may be learned by practice of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagram illustrating a time tracking device incorporated into an overhead projector in accordance with an exemplary embodiment of the present invention.
FIG. 2 is a diagram illustrating the time tracking device of FIG. 1 incorporated into a slide projector in accordance with an exemplary embodiment of the present invention.
FIG. 3 is a diagram illustrating a video conferencing set-up including a time tracking device incorporated into presentation software in accordance with an exemplary embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Detailed embodiments of the present invention are disclosed herein, however, it is to be understood that the disclosed embodiments are merely exemplary of the invention that may be embodied in alternative forms. Specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art to variously employ the present invention.
Referring now to the drawings, in which like numerals indicate like elements throughout the several figures, FIG. 1 is a diagram illustrating one embodiment of the time tracking device 10 of the present invention disposed within an overhead projector 12 . The time tracking device 10 may be disposed within the projector housing 14 , preferably within one corner of the housing surface 16 , so as not to interfere with the bulk of the usable space of the housing surface 16 . In alternative embodiments, the time tracking device 10 may be disposed within any other portion of the projector housing 14 .
The device display 18 may consist of an analog or a digital display. The display 18 is incorporated into the light stage 20 of the housing surface 16 . The device display 18 is transparent, such that the light source from within the overhead projector 12 can pass light through the device display 18 and project the analog or digital display of the timer readout onto the screen 22 . The display may consist of a liquid crystal display (LCD) providing adequate visibility to the presenter and the audience. The presentation timer control pad 24 may be disposed within the opaque portion of the projector surface 16 , such that light does not pass through the timer control pad 24 . The positioning of the timer control pad 24 separates the heat sensitive components of the time tracking device 10 from the heat generated by the projector light source. In one embodiment, the timer control pad 24 may include light emitting diodes in the function keys 26 so that a presenter can easily see the function keys 26 in a darkened room.
The timer control pad 24 consists of a plurality of function keys 26 . The function keys 26 allow a presenter and/or AV personnel to control the functions of the timer, including turning the timer on/off, starting, stopping, pausing, resetting, stopwatch, turning the display on/off, selecting various timer modes, etc. The various timer modes include displaying the elapsed time of a presentation, a countdown of the time remaining, displaying any one of the hours, minutes, seconds, displaying the time of day, etc. The function keys 26 may consist of any of several well-known types of switches, such as pushbutton switches, toggle switches, etc. The function keys 26 illustrated consist of pushbutton switches. It is preferable to have switches that lie flush with the housing surface 16 so as not to interfere with any papers or transparencies placed on the housing surface 16 , or interfere with the workspace of the projector 12 . It is also preferable to have a device display 18 that lies flush with the light stage 20 so that the device display 18 does not interfere with the working surface of the projector 12 .
The time tracking device 10 has a low power requirement. In one embodiment, the time tracking device 10 may be connected to the circuitry of the projector 12 . In a second embodiment, the device 10 is equipped with a solar panel 28 on its surface. The solar panel 28 may be located on the device display 18 , or on the control pad 24 . Positioning the solar panel on the device display 18 exposes the solar panels 28 to more light due to the light source of the projector 12 emitting light directly onto the solar panel 28 surfaces. Because of the lower power requirement of the time tracking device 10 it is not necessary that the solar panels 28 be located on the display portion. Light from the room during periods when the room is not darkened may power the timer device 10 and all of its associated functions. In a third embodiment, the time tracking device 10 may be powered using a battery. The solar panels 28 , battery, and projector power source may all be used alone or in combination to power the time tracking device 10 .
The time tracking device 10 may be cooled using the cooling mechanism of the projector 12 , typically a fan motor. The light source of a projector typically produces heat which can easily damage the components of the time tracking device 10 . The fan motor assembly forces air over the light source and other internal components of the projector in order to maintain optimal operating temperatures and prevent overheating. Solar panels 28 , batteries, and LCD displays are all sensitive to heat exposure. The fan motor also cools the projector surface 16 , particularly the light stage 20 . The timer control pad 24 is exposed to a lesser amount of heat because it is disposed within the opaque portions of the housing 14 , as compared to the light stage 20 in which the device display 18 is located.
Referring to FIG. 2 , the time tracking device of the present invention may be incorporated into a slide projector 30 . The location of the timer control pad 24 and the device display 18 of the time tracking device 10 may be similar to that of the overhead projector 12 . The timer readout is displayed to the audience via the lens 32 of the slide projector 30 . Slide projectors typically include a remote control unit 36 operable for controlling the functions of the projector 30 . In one embodiment, the function keys 26 may be located on the slide projector housing 34 . In an alternative embodiment, the function keys 26 may be located on the remote control unit 36 , making the functions of the slide projector 30 and the time tracking device 10 controllable using the remote control unit 36 alone. The timer control pad 24 may be connected to the circuitry of the remote control unit 36 , providing power and a remote connection to the projector 30 and the display 18 .
As stated above, the time tracking device 10 may be controlled by a presenter and/or AV personnel. The timer readout is projected to the audience using the light source and lens of the projection device. The function keys 26 include a “display” function key that is operable for turning the display on or off. Turning the display “on/off” provides a presenter the option of being the only person able to view the timer readout. This may be useful in an exam situation in which a timer may be a distraction to test takers. In other situations, it may desirable to display the timer readout to the audience as well as the presenter, such as during an exam in which the audience is allowed to a view a slide for a predetermined amount of time, then the projector moves onto the next slide and the timer resets and a new countdown begins.
In one embodiment, the time tracking device 10 may consist of a programmable microcomputer in which a presenter can program the timer to reset each time a new slide is selected, avoiding the need to manually reset and restart the timer for every new slide. The timer tracking device may also include a memory, which is well known in the art.
An audible, visual, and combination alarm may be a component of the control pad portion of the time tracking device 10 . An alarm may be used to cue a presenter that a certain amount of time has elapsed. In one example, students could be taking a timed exam from transparencies placed onto an overhead projector. When the exam begins, the time tracking device 10 is activated and a countdown of thirty minutes begins. The timer readout is projected onto the screen and appears in the lower left hand corner of the screen, large enough to be visible by the audience, but not large enough to distract the audience from the subject matter of the transparencies. When five minutes is remaining, the visual alarm of the timer may cause the readout to flash on and off, alerting the students of five minutes remaining. When the time has completely expired, an audible alarm, such as a “beep” may be sounded, alerting the students and the presenter that time has expired. The audible alarm may persist until it is shut off by the presenter, or may shut off after a certain time period, five seconds for example. Visual and audio alarms may be set to activate at any time period determined by the presenter.
In another embodiment, the time tracking device may be connected to the power circuitry of the projector alone, or in combination with the solar panels, or a battery, such that the time tracking device is capable of cutting the power supply to the illumination device in the projector. In such an embodiment, the time tracking device could turn the power off to the illumination device in the projector after a predetermined time so that the moderator is not the ‘bad guy’ and the machine is.
In an additional embodiment, the time tracking device 10 of the present invention may be incorporated into presentation software, such as in a video conferencing application. A computer may be connected to a display monitor. There may be up to n number of conference participants included in a video conference, where n is a number larger than two, that may visually and aurally communicate with one another. A typical video conferencing set-up is illustrated in FIG. 3 and includes a plurality of terminals. In one example, a plurality of monitors 40 linked together over a network enable conference participants to view video footage of other participants. Telephones 42 connected together, for example over a public switched telephone network (PSTN), may be used to provide participants with an audio connection. Each conference participant is able to view the conference from his/her own terminal, with the terminals being located anywhere in the world. The time tracking device 10 may be incorporated into the conference presentation software so that the timer readout is displayed onto each participant's terminal.
Timer function control may be handled by the leader of the conference or by any other participant. Timer functions may be performed using an input device, such as a keyboard, mouse, remote control unit, or like device. There are many possible programming variations of the time tracking device including the positioning of the display on the monitors, display size, and all of the timer functions discussed above.
The present invention has been described by way of example, and modifications and variations of the exemplary embodiments will suggest themselves to skilled artisans in this field without departing from the spirit of the invention. The preferred embodiments are merely illustrative and should not be considered restrictive in any way. The scope of the invention is to be measured by the appended claims, rather than by the preceding description, and all variations and equivalents which fall within the range of the claims are intended to be embraced therein. | The present invention provides a time tracking device comprising a display incorporated into a housing of a projector, a control pad, and a power source. The time tracking device can provide a presenter with the ability to track the elapsed time of a presentation. The time tracking device is further capable of being projected onto a viewing screen using the light source and lens of the projector device. The device comprises a control pad which controls the functions of the timer device, such as on/off, start, stop, pause, reset, mode, illumination, and time of day. The present invention also provides a presentation timer comprising a presentation timer program module and an input control module operable for controlling timer functions associated with the presentation timer program module. | 7 |
This invention relates generally to deal trays such as those used by cashiers for through-the-wall transactions with customers, and more particularly with a deal tray with a self-closing feature.
An earlier patent of mine is U.S. Pat. No. 4,517,901. This patent discloses a transaction drawer within a housing that can be mounted in a building wall. The housing has a front door. A drawer is glidably mounted in the housing behind the door and has a lid at its top. When the drawer is closed, the lid accommodates access of the cashier to the contents of the drawer, and the front door is closed. A cam on the drawer is operated to raise the lid to an access-excluding position as the drawer is opened, and open the door for access to the drawer by a customer outside the wall. The cam on the drawer and lid have different rates of actuation so that the lid is closed more quickly than the door is opened. This device is not always viable for use in some applications.
There is a need for a less expensive deal tray that can be readily locked closed by an employee at the end of the day or between transactions than is currently available. This invention is one solution that addresses that need.
SUMMARY OF THE INVENTION
In one aspect, this invention is a deal tray for transactions between a location in front of a barrier and a location behind a barrier. The deal tray has a frame with at least a partially open top and at least a partially closed bottom. A receptacle rests in the frame and is movably connected to the front face of the frame. The movable receptacle moves between a lowered position toward the bottom of the frame and a raised position away from the bottom of the frame. A leg is movably attached to the bottom of the receptacle. The leg moves from a supine position when the receptacle is lowered to an erect position when the receptacle is raised.
In another aspect, this invention is an improvement for the combination of a countertop and a transaction barrier. The improvement is a deal tray that is mountable between the external side and internal side of the barrier. The deal tray has a frame with at least a partially open top that can also be secured within the top surface of the countertop. The deal tray further has a movable receptacle that is hingedly connected to the front face of the frame. The movable receptacle can then move between a lowered position away from the barrier above it and a raised position against the barrier above it. Finally, the deal tray includes a support hingedly attached to the bottom of the movable receptacle that can be moved between a supine position and a standing position, respectfully corresponding to the receptacle's lowered and raised positions.
BRIEF DESCRIPTION OF THE DRAWINGS
In the accompanying drawings, forming a part of this specification, and in which like numerals are employed to designate like parts throughout the patent:
FIG. 1 is a perspective view of the deal tray with the receptacle in the raised or closed position and showing the placement of the deal tray in a countertop in the barrier in a building according to one embodiment of the invention.
FIG. 2 is a perspective view of the deal tray with the receptacle in the lowered or open position and showing the placement of the deal tray in a countertop in the barrier in a building according to one embodiment of the invention.
FIG. 3 is a cross-sectional view of the deal tray with the receptacle in the raised or closed position according to one embodiment of the invention.
FIG. 4 is a cross-sectional view of the deal tray with the receptacle in the lowered or open position according to one embodiment of the invention.
FIG. 5 is a plan view of the deal tray according to one embodiment of this invention.
FIG. 6 is a fragmentary view showing one embodiment of a slidable sealing engagement according to one embodiment of this invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
For the purpose of promoting an understanding of the principles of the invention, specific language is used to describe the embodiments of this invention that are illustrated in the drawings. Please understand that no limitation of the scope of the invention is intended by this description. Any alteration and modification to the illustrated device that would normally occur to one of average skill in this art are also included.
As used in this patent the term “arcuate” is used with its ordinary meaning of bent or curved or bowed.
As used in this patent the term “clearance” is used with its ordinary meaning of the distance by which one object clears another.
As used in this patent the term “concave” is used with its ordinary meaning of curved or rounded inward like the inside of a bowl.
As used in this patent the term “frame” is used with its ordinary meaning of an open case or structure made for admitting, enclosing, or supporting something.
As used in this patent the term “leg” is used with its ordinary meaning of structure serving as a support or prop.
As used in this patent the term “median plane” is used with its ordinary meaning of a vertical longitudinal plane that divides an object into right and left portions.
As used in this patent the term “receptacle” is used with its ordinary meaning of structure that can receive and contain or hold something.
As used in this patent the term “standing” is used with its ordinary meaning of upright on the feet or base: erect.
As used in this patent the term “supine” is used with its ordinary meaning of lying on its back or with a face generally upward.
Referring to the attached drawings, FIGS. 1 and 2 depict a preferred example of the deal tray 7 when it is respectfully in a raised position and in a lowered position according to the principles of the invention. One feature of deal tray 7 readily noted is frame or housing 8 . See also FIGS. 3-5. Frame 8 preferably includes lateral sides 9 and 10 , front face 11 , bottom 12 , an open top 13 , and a back face 15 . Frame 8 also preferable includes a flange 14 that laterally extends from the top edges of front face 11 , lateral sides 9 and 10 , and back face 15 .
Referring to FIGS. 3 and 4, bottom 12 is preferably not horizontal. Rather, bottom 12 is preferable tilted so that any rainwater, which happens to fall into frame 8 drains toward back face 15 on the exterior side 18 of barrier 19 instead of draining toward front face 11 on the interior side 20 of barrier 19 . This optional feature is preferably accomplished during the manufacture of frame 8 by constructing front face 11 of comparatively less width 22 than the width 21 of back face 15 and appropriately tapering lateral sides 9 and 10 in a fashion to compensate for a bottom 12 that has a slight incline or upward curve from the bottom edge 16 of back face 15 to the bottom edge 17 of front face 11 . Frame 8 then includes a passageway 23 preferably located in the lowermost portion of frame 8 through which the rainwater may drain out from frame 8 .
FIGS. 1-5 depict a frame 8 with a fully closed bottom and a fully open top 13 , however, this is not necessary to practice the invention protected by this patent. The top 13 need only be partially or sufficiently open to allow a customer standing on the exterior side 18 to pass items to the interior side 20 . Meaning, the top 13 possibly may be partially obstructed by accessories, a cover, or other structures and still practice the principles of this invention. The bottom 12 need only be partially or sufficiently closed so that leg or support 24 has some structure or structures on which it may stand when leg 24 is in an extended position. For example, such structure could even be provided by the barrier 19 in which deal tray 7 is mounted and still practice the principles of this invention.
Frame 8 may be constructed from many materials including those materials particular suitable for exposure to the elements of weather, such as stainless steel or fiber-reinforced plastics. For example, a highly preferable material is 16- or 10-gauge stainless steel.
Deal tray 7 further includes a receptacle 25 . Referring to the figures, receptacle 25 has a top surface 26 , a bottom surface 27 , lateral edges 28 and 29 , a front portion 30 , and a back portion 31 . Receptacle 25 is generally sized to fit within frame 8 . The front portion 30 of receptacle 25 is movably attached to the front face 11 of frame 8 by a hinge 32 . As shown, hinge 32 is preferably of the piano hinge variety and extends the entire width 33 of receptacle 25 . And although a piano hinge is shown, it is contemplated by this invention that one may also use similarly operating structures such as a flexible membrane of plastic or rubber secured between receptacle 25 and front face 11 or use multiple hinges, rather than a single hinge, attached over the width of receptacle 25 to the front face 11 .
The front portion 30 of receptacle 25 is preferably substantially flat. When in its lowered position shown in FIG. 4, the flat surface allows items to side down receptacle 25 to the bottom 34 of receptacle 25 , preferably on the inside 20 of barrier 19 . (FIG. 2) The flat surface also provides a cover that portion of open top 13 of the outside 18 of barrier 19 when receptacle 25 is in a raised position. (FIG. 1) And although a substantially flat front portion 30 is shown, it is contemplated that the surface of front portion 30 could also be convex as well as concave and still accomplish the principles of the invention. In other words, it is not an absolute requirement that front portion 30 be flat in order to practice this invention. Most any surface configuration over front portion 30 would suffice.
The back portion 31 of receptacle 25 preferably includes a concave curved portion 35 . In one embodiment of this invention, the concave curved portion resides in a medial plane 36 , the cross-section of which being shown in FIGS. 3 and 4. Relevant here, although receptacle 25 is shown only curved along this medial plane, it is also contemplated that back portion 31 of receptacle 25 could be simultaneously curved along other planes as well. Allowing, for example, the back portion to resemble the shape of a parabola or bowl and still practice the principles of this invention. In other words, preferably back portion 31 simply includes some form of an arcuate surface to receive items sliding down the front portion 30 of receptacle 25 into back portion 31 .
Receptacle 25 further includes a handle 37 . Handle 37 is preferably attached to the proximal end 38 of receptacle 25 . In one embodiment, handle 37 is a flange that extends over the entire width 33 . This flange then rests upon the top edge 38 of back face 11 when receptacle 25 is placed it is lowered position. In other embodiments, handle 37 may be simply attached to the top surface 26 of receptacle 25 .
The respective clearance between the lateral edges 28 and 29 and the lateral sides 9 and 10 can be most any that will allow receptacle 25 to pass inside frame 8 . In one embodiment nor more than one-half of an inch is contemplated. In another embodiment no more than one-quarter of an inch is contemplated. Be that as it may, it is further contemplated that one could also use a weather-tight seal 40 between lateral edge 28 and side 9 and a weather-tight seal 40 between lateral edge 29 and side 10 . This seal 40 could be made of an appropriate elastomeric material such as silicone rubber, natural rubber, or nylon fibers, and could be attached along the lateral edges 28 and 29 to ride against sides 9 and 10 . A cross-sectional view of such an arrangement is shown in FIG. 6 . In this arrangement seal 40 is held in bracket 41 and bracket 41 is attached along the length of lateral edges 28 and 29 while allowing the seal 40 to extend over the clearance between receptacle 25 and frame 8 to contact its lateral edges 9 and 10 .
Similar to frame 8 , receptacle 25 may be constructed from many materials including those materials particular suitable for exposure to the elements of weather, such as stainless steel or fiber-reinforced plastics. For example, a highly preferable material is 16 or 10-gauge stainless steel.
Deal tray 7 further includes a leg or support 24 . Referring to FIGS. 3 and 4, leg 24 resides between the bottom surface 27 of receptacle 25 and the bottom 12 of frame 8 . Leg 24 is movably attached to the bottom surface 27 , which as shown, is most preferably done with hinge 43 . But although a hinge is shown, it is further contemplated that other methods of connection could be used, for example, one could also use a pivot, a universal joint, or swivel connection between leg 24 and receptacle 25 . In one embodiment, leg 24 is substantially wide, being made of one continuous piece. In another embodiment, leg 24 could include multiple legs attached to the bottom surface 27 of receptacle 25 and be either attached to operate in unison or unattached to operate independently. Leg 24 is designed to move from a supine position as shown in FIG. 4 and a standing position shown in FIG. 3 . Leg 24 further preferably includes a foot 44 at its bottom to assist in maintaining leg 24 in a standing position. Leg 24 , like most of the deal tray 7 , may be constructed from many materials including those materials particular suitable for exposure to the elements of weather, such as stainless steel or fiber-reinforced plastics. For example, a highly preferable material is stainless steel.
Referring to FIGS. 1 and 2, deal tray 7 is mounted within a building by placing deal tray 7 within a countertop 45 that in turn resides in an opening 47 in one of the barriers 19 of the building. Barrier 19 preferably includes a clear but bulletproof portion 46 that allows one to see from the internal side of the booth to the external side and vice versa. Materials and methods of the construction of such countertops and barriers are well known in the art.
A final aspect of the present invention is the manner in which deal tray 7 closes preventing access from the exterior 18 . In its lowered or open position (FIGS. 2 and 4 ), receptacle 25 has a comparatively lower position in frame 8 to allow for passage of items from the external side 18 to the internal side 20 of barrier 19 over the top of receptacle 25 . While in this lowered position, leg 24 is supine, resting preferably on its side against the bottom 12 of frame 8 . When the transaction is complete, the clerk locks deal tray 7 closed by lifting receptacle 25 against the bottom 48 of opening 47 . Once lifted to this position, leg 24 moves or swings to a standing position (FIG. 1 or 3 ) between receptacle 25 and the bottom 12 of frame 8 to continue holding receptacle 25 against barrier 19 . The deal tray now prevents access from the exterior 18 because the front portion 30 residing outside barrier 19 is still in the confines of frame 8 , leaving only the clearance, if any, between the lateral edges 28 and 29 of receptacle 25 and the lateral sides 9 and 10 of frame 8 to allow passage to the inside. The clerk on the inside 20 of barrier 19 can reopen deal tray 7 by moving leg or legs 24 from its standing position and relocating receptacle 25 to its open position with leg or legs 24 back in a supine position.
While the invention has been illustrated in the drawings and described in detail in the description, these are to be considered as illustrative and not restrictive. It must be understood that preferred embodiments have been shown and described and that all changes and modifications that come within the spirit of the invention are included where described by the following claims. | A self-locking deal tray for use in a countertop and a transaction barrier. The deal tray has a frame with at least a partially open top and can be secured to the countertop. The deal tray further has a movable receptacle that is movably connected to the front face of the frame. The movable receptacle can then move between lowered position away from the barrier above it and a raised position against the barrier above it. Finally, the deal tray includes a support movably attached to the bottom of the movable receptacle that can be moved between a supine position and a standing position, respectfully corresponding to the receptacle's lowered and raised positions. | 4 |
BACKGROUND OF THE INVENTION
The present invention relates to a manifold system for controlling the operation of safety control valves, particularly in production wells for petroleum products.
In the course of operation of a production well via which a product such as gas or oil is being extracted from an underground deposit and delivered to a pipeline connected to the wellhead and located at or just below the ground surface, there are occasions when it is necessary to halt the flow of the product. Such an operation may be necessary, for example, to permit routine maintenance operations or to prevent spills in the event of an accident or equipment breakdown.
As a result, it has long been the practice in the industry to place at least one shut-off valve in the product flow path, such valve being conventionally located at the wellhead, i.e., essentially at the ground surface. However, location of a shut-off, or safety, valve essentially at the ground surface presents certain drawbacks, particularly since certain types of accidents could damage, or destroy, a valve at that location, in which event the valve could no longer act to block the flow of production fluid.
Therefore, it has more recently become the practice to insert a subsurface shut-off, or safety, valve in the well tubing which conducts the production fluid to the wellhead. Such subsurface valve can be disposed at any depth below the ground surface and is provided with an operating unit connected to systems located at the surface to effect remote control opening and closing of the valve.
The choice of depth for the location of such a subsurface valve is based on a number of considerations, including the depth to which a foreseeable accident occurring at ground level could damage such a valve, external conditions relating, for example, to the climate in which the well is located, and legal requirements. Consideration must also be given to the fact that the cost of installing, servicing, or replacing such a valve increases as a function of the depth at which the valve is to be located.
For example, in the case of a production well located in the North Slope of Alaska, where the permafrost layer extends to depths in excess of 2,000 feet, both State and Federal laws require that the subsurface safety valve, which is ordinarily a ball valve, be located below the permafrost level, and thus at a depth in excess of 2,000 feet. Since repair or replacement of a valve located at such a depth can be expected to be enormously expensive, particularly in the Arctic where, in view of the severe weather conditions, such replacement could conceivably cost $1,000,000 or more, it is important that steps be taken to avoid the need for servicing or replacing the subsurface valve.
For these reasons, it is desirable to dispose in the product flow path two valves, one located at the required level below the surface and one located at the surface, and to operate the valves in sequence in a manner to prevent the subsurface valve from opening or closing against high dynamic pressure loads or high flow rates.
In order to block the flow of production fluid from such a well in the event of an accident, it is a general practice to provide monitoring equipment which senses certain conditions, such as the pressure or rate of flow of product at the wellhead, the temperature of the environment surrounding the wellhead, ets. and to connect this monitoring equipment to effect closing of the safety valve, or valves, upon the occurrence of a condition indicating that an accident or malfunction has taken place. Of course, when such a condition is sensed, it is desirable that the safety valve, or valves, close a rapidly as possible.
In many cases, it is also desirable that the response of the system to an unsafe condition indication, or the sensitivity of the system be adjustable to compensate for changes in external conditions which can influence the operation of the system, or for unavoidable changes in the operating characteristics of various components of the system. It may also be desirable to be able to vary the speed of response of the system to an indication of an unsafe condition if, for example, external factors make it undersirable to close the safety valve, or valves, in the shortest time that the capabilities of the sytem permit.
On the other hand, it is equally desirable that the system which acts to close the valve, or valves, in response to the indication of an unsafe condition be as simple as possible since the reliability of any system is directly related to its structural simplicity.
SUMMARY OF THE INVENTION
It is a primary object of the present invention to improve both the reliability and operating speed capability of such a system.
A further object of the invention is to improve the operating flexibility of such a system by permitting its response speed to be adjustable over a substantial range and by permitting its sensitivity to be adjusted to compensate for changes in external conditions.
Another object of the invention is to permit the response speed and sensitivity of such a system to be adjusted in a rapid and simple manner.
A further object of the invention is to provide a system of this type which is structurally quite simple.
These and other objects according to the invention are achieved, in a system for closing a primary valve disposed in in the flow path of a primary fluid, in response to an indication of an undersirable condition from a monitoring device, the opening and closing of the primary valve being controlled by the pressure of an operating fluid supplied thereto, and the system being composed of input means arranged to be connected to the monitoring device to receive therefrom an indication of the condition being monitored, output means arranged to supply operating fluid to the primary valve, valve means connected with the output means for controlling the pressure of the operating fluid at the output means, and fluid-responsive operator means having an input operatively associated with the input means for receiving a control fluid, the operator means being connected to the valve means for switching the valve means between a state which causes the pressure at the output to effectuate opening of the primary valve and a state which causes the pressure at the output to effectuate closing of the primary valve, and the pressure of the control fluid at the operator means when an indication of an undesirable condition is present at the input means having a value which causes the operator means to switch the valve means into the state which causes the operating fluid pressure at the output means to effectuate closing of the primary valve, by the improvements involving providing the system with a conduit which is connected to establish direct fluid communication between the operator means input and the input means, such that control fluid is present at the input means, by arranging the system so that the control fluid pressure at the input means is determined by the indication received from the monitoring device, and by arranging the operator means to switch the valve means into the state which results in closing of the primary valve when the control fluid pressure at the operator means input corresponds to the control fluid pressure created at the input means when an indication of an undesirable condition is received from the monitoring device.
The objects according to the present invention are further achieved by providing an adjustable metering valve in series in the conduit means.
The objects according to the invention are further achieved by providing a pump which is driven by the control fluid and which consitutes a source of pressurized operating fluid, the operating fluid output pressure produced by the pump being proportional to the control fluid input pressure thereto, and by causing the operating pressure to at least a portion of the operator means to be proportional to the control fluid pressure supplied to the pump so that the force supplied by such operator means to the associated valve means will remain substantially proportional to the operating fluid pressure produced by the pump.
BRIEF DESCRIPTION OF THE DRAWINGS
The single FIGURE is a schematic diagram of a preferred embodiment of a safety control valve system according to the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The FIGURE illustrates a system according to the present invention having a pneumatic signal input 6 connected to any suitable condition monitoring devices, the choice of which depends on the particular characteristics and operating conditions of the wells to be controlled. One typical monitoring device is a pilot valve disposed to monitor the pressure in a section of pipeline conducting fluid away from the valve and to produce an unsafe condition indication if the pressure should decrease below a selected value. It is also known to provide pilot valves which produce an indication if the pressure in the pipeline exceeds a selected value. Other monitoring devices, such as temperature sensors, can also be connected to the manifold, at the point of connection 6.
The illustrated manifold is intended to control one or more production wells of the type provided with a surface safety valve, a subsurface safety valve and a balance line.
The surface safety valve is usually the upper master valve provided on the Christmas tree located at the wellhead. This valve is a hydraulically operated valve which opens when the pressure supplied thereto exceeds a predetermined value and closes when the hydraulic pressure drops below a predetermined value. Similarly, the subsurface safety valve, which is normally a ball valve, is controlled to open when the pressure of the hydraulic control fluid supplied thereto exceeds a selected value and to close when the pressure of that fluid drops below a selected value.
According to standard field practice, these valves are operated in a sequence which assures that opening of the subsurface valve will not occur against the full well pressure differential and that closing of the subsurface valve will not be effected againts a full flow of production fluid. As a result the useful life and reliability of the subsurface valve will be increased. Thus, in accordance with standard practice, flow from the well will be initiated by first opening the subsurface valve and subsequently opening the surface valve, whereas shut-down will be effected by first closing the surface valve and subsequently closing the subsurface valve.
The delivery of hydraulic control fluid to the subsurface valve could be effected via a stainless steel line which runs down the well along the production tubing to the subsurface ball valve. Since the subsurface valve is disposed below ground level, the volume of hydraulic fluid in the control line will produce a certain pressure head and the greater the depth at which the subsurface valve is located, the higher will be the fluid head pressure at the operating unit of the subsurface valve. In order to prevent this static pressure head from adversely affecting the operation of the subsurface valve, a second stainless steel line is run, parallel to the first line, to the operating unit of the subsurface valve. This second line is referred to as a balance line and serves to provide a second pressure head which balances or compensates for the static pressure in the control line. Typically, the hydraulic pressure applied, at the surface, to the balance line is of the order of 20 to 100 psi.
The manifold illustrated in the Figure is thus provided with separate hydraulic outlets for connection to, respectively, the control input of the surface safety valve, the control input of the subsurface safety valve, and the input end of the balance line.
It will be seen from the above that a well control manifold system according to the invention is composed of a pneumatic subsystem and a hydraulic subsystem. The pneumatic paths are illustrated in the Figure by double lines representing air conduits, while the hydraulic paths are illustrated by single lines to be distinct from the pneumatic lines.
The pneumatic subsystem constitutes the input and control signal generating portion and the hydraulic subsystem controls the supply of operating fluid to the various lines associated with the well and is in turn controlled by the pneumatic subsystem.
The pneumatic subsystem includes a manually operable valve 1 connected to a source 2 of air under pressure which supplies the air for operating this subsystem. Connected to valve 1 is an air regulator 3 which is adjusted to supply a controlled quantity of air to the system.
Connected to regulator 3 is a parallel arrangement of a normally closed air operated valve 4 and a spring-biassed, manually operable, normally closed toggle valve 5.
The operator portion 4' of valve 4 is connected to a pneumatic signal input 6 to receive a pneumatic control signal from any condition monitors provided to effect closing of the well upon the occurrence of particular conditions. The operator part 4' of valve 4 is also connected to the other side of the flow path defined by that valve and to the other side of valve 5, as well as to the normally open port of a manually-operated three-way valve 8, via an accurately adjustable metering valve 10 providing a passage of variable diameter. Valve 8 may be a ball valve.
Air regulator 3 is also connected to deliver driving air to air-driven hydraulic fluid pump 20.
The common port of three-way valve 8 is connected to the operators 21' and 22' of air operated hydraulic fluid control valves 21 and 22. Valve 21 is normally closed while valve 22 is normally open, these being the states which they assume when the air pressure in their operators drops below a particular value.
All of the remotely-controlled valves illustrated in the Figure are shown in their normal state. The form in which the valves are illustrated is selected to permit easy understanding of their operation and is not intended to suggest any specific form of construction. Thus, each valve in the system can be a slide valve, ball valve, flap valve, etc.
Pump 20 has its inlet side connected to the supply outlet of a hydraulic fluid reservoir 19 and its outlet side connected to one side of valve 21. The other side of valve 21 is, in turn, connected to one side of valve 22 while the other side of the latter valve is connected to a line for returning hydraulic fluid to reservoir 19.
The conduit connected between valves 21 and 22 is also connected to a manually-operated shut-off valve 23 whose other side is connected to a series arrangement of a manually operated valve 25 and a relief valve 27 leading to the return line to reservoir 19.
The other side of valve 23 is further connected to a series arrangement of manually-operated valves 30 and 32 leading to the well system balance line. Valve 30 is an isolation valve which isolates the balance line from the pump output. The point of connection between valves 30 and 32 is connected, via a further manually-operated valve 36 and a relief valve 38, to the reservoir fluid return line.
The other side of valve 23 is also connected to the control line for the well system surface safety valve via a manually adjustable metering valve 40 connected in parallel with a high pressure check valve 42 arranged to permit fluid flow only in a direction away from the surface safety valve, and to the control line for the well system subsurface safety valve via a manually adjustable metering valve 44 connected in parallel with a check valve 46 arranged to permit fluid flow only in a direction toward the subsurface safety valve.
The system is completed by a hand pump 50 which can be used to manually operate the system in case of failure of the air supply, hydraulic pump, or valve 21 or 22, and under conditions which permit the safety devices to be bypassed. Also provided are several pressure gauges 52, 53 and 54 which help an operator to monitor the operation of the system.
To begin operation of the system, valve 1 is opened to conduct air under pressure from supply 2 to air regulator 3 which regulates the air pressure for the remaining portion of the pneumatic subsystem.
The regulated air is delivered to air-driven pump 20 which pumps hydraulic fluid out of reservoir 19. The air from regulator 3 is also supplied to one side of air operated valve 4 and one side of toggle valve 5, both of which are in their normal, closed, states during system start-up.
Then, to activate the system, valve 5 is manually opened, and held open, to supply the air pressure to metering valve 10 and through that valve to pressure gauge 52 and to the control input of valve 4, which is also connected to the input 6 for receiving pneumatic control signals from, for example, a pilot monitoring the pressure in the pipe conducting product from the well, or fusable plugs, gas monitoring equipment, etc. Any variety and number of specific devices can be connected to input 6 and these can be changed periodically as conditions at the well change.
As air flows through valve 10, the pressure in the section downstream thereof increases until reaching a level at which valve 4 is opened to provide a flow path parallel to that of valve 5, so that the latter can be permitted to close.
At the time that valve 5 is opened, air under pressure is also supplied through three-way valve 8 to the operator portions 21' and 22' of valves 21 and 22. A short time after opening of valve 5, the pressure at operators 21' and 22' will rise to a level at which valves 21 and 22 are actuated, so that valve 21 will open to open the hydraulic flow path from pump 20 and valve 22 will close to block return of the hydraulic fluid to the reservoir 19.
Under all normal operating conditions, manually activated valves 23 and 25 are open, so that upon opening of valve 21, the hydraulic pressure is transmitted via valves 23 and 40 to the surface safety valve, and via valves 23 and 44 to the subsurface safety valve.
To apply pressure to the balance line under normal condition, valves 36 and 32 are opened and valve 30 is opened briefly allowing the pressure in this line to reach a point that is determined by relief valve 38. Valve 38 is a preset relief valve. When this point is reached valve 30 is closed.
Valves 40 and 44, being adjustable metering valves, are set to provide fluid flows required to operate the safety valves in the desired manner. In addition, upon opening of valve 21, hydraulic pressure fluid will flow through check valve 46 to the subsurface safety valve, but will not flow through valve 42 to the surface safety valve. Based on the setting of valves 40 an 42, and the flow of hydraulic pressure fluid through valve 46, there will be a higher volume flow to the subsurface safety valve so that this valve will open before the surface safety valve, which is the sequence desired so that the subsurface safety valve will not have to open against the full well pressure differential.
Relief valve 27 is set to open, to provide a return path to the reservoir, if the pressure in the line from valve 23 exceeds a predetermined value, while valve 38 is set to open if the pressure downstream of valve 30 exceeds the selected balance line pressure. Valve 38 allows for expansion in the balance line due to heating which occurs when the well starts to flow and thus prevents high pressure from developing in the balance line when such heating occurs.
Pressure gauge 54 indicates the presence of positive pressure in the balance line, while gauge 53 indicates the pressure being supplied to the safety valves and gauge 52 indicates the pneumatic pressure in the monitoring signal lines.
If, for any reason, a higher pressure is to be created in the balance line, valves 30 and 36 would be closed, valve 32 would be open, and hand pump 50 would be operated until the desired higher pressure had been reached.
Shutdown of the system, involving closing both safety valves, can be effected automatically in response to a shut-down signal from any one of the monitoring devices connected to input 6.
The pneumatic shut-down signal will be in the form of a pressure drop at input 6. This will reduce the pressure in the operator part 4' of valve 4 to a level at which the valve closes, valve 5 having previously been permitted to close at the end of the start-up phase.
Upon closing of valve 4, the supply of air under pressure to operators 21' and 22' is terminated and as soon as a sufficient quantity of air bleeds out of these operators, via valve 10, valves 21 and 22 close, blocking the hydraulic pressure transmission between pump 20 and the safety valves while providing a path, via valve 22, for flow of hydraulic fluid from the lines connected to the safety valves back to the fluid reservoir.
Pressure fluid can flow from the subsurface safety valve only via its associated metering valve 44, but can flow from the surface safety valve via both its associated metering valve 40 and its associated check valve 42. Therefore valve 44 can be easily adjusted to assure that hydraulic control fluid will flow from the surface valve more rapidly than from the subsurface valve so that the surface valve will close before the subsurface valve. This closing sequence provides additional protection for the subsurface valve by preventing it from closing against full well flow.
Whenever desired, closing of the surface and subsurface safety valves can be initiated manually simply by switching valve 8 to place its common port in communication with its normally closed port which communicates with a vent outlet, for example to the external atmosphere. This causes rapid venting of the air in operator parts 21' and 22' and thus rapid return of valves 21 and 22 to their normal states
When it is desired to rely on hand pump 50 to provide the hydraulic pressure for opening the surface and subsurface safety valves, valves 23, 32 and 36 must be closed and valve 30 opened. Then pump 50 is operated to produce the necessary operational pressure, which can be monitored by gauge 53. With this mode of operation, the safety system is ineffective and no pressure is being applied to the balance line.
Valve 25 is provided to permit the application to the subsurface safety valve of a hydraulic pressure greater than that to which relief valve 27 is set. This may be necessary if the subsurface safety valve should experience a malfunction causing it to stick in its closed state.
When a shut-down, or shut-in, signal appears at input 6, this signal being in the form of a drop in the pressure in the conduit at input 6, it is of course desirable that the system respond with a high degree of reliability. In addition, it is usually desirable, if not essential, that a safety system respond rapidly. The present invention permits both of these goals to be realized in a particularly advantageous manner by providing an essentially direct fluid-transmitting connection, without any intermediate active devices between the operators 21' and 22' and signal input 6, as well as between operator 4' and input 6. This direct connection between the signal input and the operators of the valves whose operation directly determines the pressure of the fluid that operates the well safety valves results in a structurally simple arrangement. The directness of the connection permits achievement of a rapid system response and, in conjunction with its structural simplicity, establishes a high level of reliability.
Furthermore, the operating flexibility of the system according to the invention, and its ability to be adapted to varying operating conditions and requirements, are greatly enhanced by the provision of the adjustable variable-orifice metering valve 10 between input 6 and operator 4', on the one hand, and one side of the flow control portion of valve 4 and operators 21' and 22', on the other hand. The variability of the diameter of the flow passage, or orifice, of valve 10 permits a simple but accurate adjustment of the air flow between the flow path provided by valve 4 and the input to its operator 4'.
Upon receipt of a shut-in signal at input 6, the first phase of the system response is closing of valve 4. This requires bleeding of a certain quantity of air from valve operator 4'. In a preferred embodiment of the invention, valve 4 could be constituted by a commercially available model whose operator 4' has an internal volume of 0.6 cubic inches, so that only a small quantity of air would have to be bled off from operator 4' to effect closing of valve 4.
Upon closing of valve 4, and since toggle valve 5 was previously closed at the end of the starting phase of system operation, the supply of air under pressure to operators 21' and 22' is blocked. Each valve 21 and 22 could, in the preferred embodiment of the invention, be constituted by a commercially available model having an operator with an internal volume of about 1.6 cubic inches and the tubing between operators 21' and 22' and input 6 could be designed to have an internal volume of about 0.5 cubic inches so that subsequent to closing of valve 4, less than five standard cubic inches of air would have to be vented in order to effect closing of valves 21 and 22, after which the surface and subsurface safety valves will close in the proper sequence.
Valve 10 and operator 4' constitute, in effect, an air system which is separately adjustable, by adjustment of valve 10, to vary the response and sensitivity of the entire safety system over a fairly wide range. In fact these elements can be considered to be the heart of the entire safety system.
If valve 10 is opened to its maximum flow passage diameter, the volume of air which must be vented off, after a pressure drop appears at input 6, would be a maximum, primarily because of the continuing flow of air under pressure through valve 4. For example, in the preferred embodiment of the invention, this might make it necessary to vent 20 standard cubic inches of air before valve 4 will close. This would constitute a setting of the system to its lowest sensitivity level.
Conversely, if valve 10 is adjusted almost to its closed position, it might only be necessary to vent 0.8 standard cubic inches of air, after a pressure drop appears at input 6, to effect closing of valve 4, and this would constitute a setting of the system to its highest sensitivity level.
While it might normally be desired for the system to be set to its highest sensitivity level, conditions will arise in the field which make it desirable that the sensitivity of the system be reduced. This can be accomplished simply by varying the setting of valve 10, without interrupting the operation of the system. If valve 10 were not adjustable, this sensitivity variation could be achieved only by shutting down the system and replacing the valve.
Moreover, use of a variable orifice valve in accordance with the present invention permits continual operation of the system at its high sensitivity setting while assuring that the integrity of the safety system will be reliably maintained. As mentioned above, the highest sensitivity setting corresponds to a minimum orifice size. By way of example, in a preferred embodiment of the invention, attainment of the desired high sensitivity level would require an orifice 1/4 inch long and 1/80 inch in diameter. Such an orifice would be highly prone to plugging and a plugged orifice would prevent the system from being placed in operation, because pressure medium could not reach operator 4'.
In contrast, an adjustable valve is less prone to plugging and if plugging should occur, the valve need only be opened slightly to alleviate the condition while reestablishing the desired high sensitivity state.
An additional advantage of a variable orifice valve is that it permits the safety system to be rapidly and accurately adjusted, while maintaining the desired sensitivity, to any addition or removal of monitoring devices.
In order for the disclosed system to operate properly, the flow rate through that one of the connected monitoring devices which produces the lowest flow rate when actuated must be greater than the flow rate from regulator 3 through valve 10. The adjustability of valve 10 enables the system to be readily adapted to any change in the number or nature of the monitoring devices.
Furthermore, monitoring devices and the lines connecting them to input 6 are likely to present small leaks which must be compensated by the air flow through valve 10. As more monitoring devices are connected to a system, the chance that such leaks will occur, and the possible leakage flow rate, will increase. With a fixed orifice at the location of valve 10, it could easily occur that these leaks would produce a shut-in signal. The variable orifice valve according to the invention permits compensation for such leaks together with maintenance of the desired sensitivity.
The variable orifice valve 10 also permits the system to be easily adjusted to the decreases which occur in the flow rates of gases through small diameter lines at low temperatures, particularly the extremely low temperatures found in artic environments, such as on the Alaskan North Slope.
It is realized that decreasing the orifice size in valve 10 will result in a slower bleeding of the air in valves 21 and 22 during a shut-in signal, however, since the volume of air is less that 4 standard cubic inches in this system, the overall effect of a smaller orifice setting is negligable. This has been confirmed by actual field testing.
Proper operation of the system according to the invention is further aided by provision of regulator 3, and by connection of both the pump drive and operators 21' and 22' to the output side of the regulator. Since pump 20 generates an hydraulic output pressure which is proportional to the pneumatic drive pressure which it receives, and the operating force within valves 21 and 22 must correspond to the hydraulic pressure against which they must act, this connection assures that any increase in the pump output pressure will be accompanied by a corresponding increase in the operating forces applied by operators 21' and 22' to their respective valves 21 and 22. Thus the pressure to operators 21' and 22' is always proportional to the drive pressure supplied to pump 20 so that any increase in the pump hydraulic output pressure will automatically be accompanied by an increase in the valve operating forces valves 21 and 22.
In the preferred embodiment of the invention to which reference has already been made, regulator 3 could be a standard component capable of delivering 30 cubic feet of air per minute at a pressure of 0 to 100 psi. As mentioned earlier, the valves 4, 21 and 22 could be of types whose operators have internal volumes of 0.6, 1.6 and 1.6 cubic inches, respectively. In addition, valves 21 and 22 can each be of the type having a regulating type stem which causes the valve to switch in a manner to cause the pressure at the subsurface safety valve operator to change gradually to reduce the possibility of damaging that valve by sudden pressure pulse. Valve 10 could be constituted by any commercially available very fine metering valve having a suitable orifice variation range. Each of valves 21 and 22 should be of a type capable of handling up to 6,000 psi hydraulic pressure at their high pressure side. Valves 40 and 44 could each be a metering valve with a slightly higher C v factor than valve 10.
A C v factor is a flow rate number arrived at using the following flow formulas for liquids recommended by the Fluid Controls Institute, Inc.:
Q = C.sub.v √ΔP/SG (1)
c.sub.v = Q√SG/ΔP (2)
Δp = [q.sup.2 (sg)]/c.sub.v 2 (3)
where:
Q = Flow in U.S. gallons per minute;
ΔP = Pressure drop (PSI);
sg = specific gravity of fluid (Water = 1.0); and
C v = Valve flow coefficient.
Relief valve 27 could be adjustable to open at a value between 2,000 and 5,000 psi, while relief valve 38 is preferably adjustable to a relief pressure value in the range between 20 and 100 psi.
Pump 20 could be similar to models manufactured by Haskell constituting a direct ratio pump having a hydraulic output pressure/pneumatic input pressure ratio of 50:1 to 100:1. In a system according to the invention, the pump could receive air at a pressure of 60 psi to pump oil at a pressure of 3,000 to 3,600 psi.
It will be understood that the above description of the present invention is susceptible to various modifications, changes and adaptations, and the same are intended to be comprehended within the meaning and range of equivalents of the appended claims. | In a safety system for controlling the closing of a primary valve in response to an indication of an undesirable condition from a monitoring device, the system including a valve arrangement which supplies operating fluid to the primary valve and an operator connected between the monitoring device and the valve arrangement for controlling the operation of the latter in response to the indication produced by the monitoring device, the speed and reliability of the system is improved by providing a direct fluid connection between the output of the monitoring device and the operator, whereby the system is directly controlled by the fluid pressure variations at the output of the monitoring device. Preferably, the system includes an hydraulic subsystem and a pneumatic subsystem. | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to and the benefit of co-pending U.S. provisional patent application Ser. No. 61/776,454, filed Mar. 11, 2013, which application is incorporated herein by reference in its entirety.
FIELD OF THE INVENTION
[0002] The invention relates to apparatus used in research in general and particularly to apparatus that allows in situ experimental visualization.
BACKGROUND OF THE INVENTION
[0003] Rechargeable batteries are known to fail unexpectedly via short-circuiting through metallic dendrites that grow between electrodes upon recharging. This phenomenon triggers a series of events that begin with overheating, eventually followed by the thermal decomposition and ultimately the ignition of the organic solvents used in such devices. This flaw has become a major safety issue in the operation of the recently introduced larger passenger aircraft.
[0004] Many efforts have focused on exploring the effects of chemical composition and morphology of various electrode materials (see J. M Tarascon, M. A., Issues and challenges facing rechargeable lithium batteries. Nature, 2001 414: p. 359-367; Armand, M. and J. M. Tarascon, Building better batteries. Nature, 2008. 451 (7179): p. 652-657) and the nature of solvents and electrolytes (see Xu, K., Nonaqueous liquid electrolytes for lithium - based rechargeable batteries. Chem Rev, 2004. 104 (10): p. 4303-417) on the energy density and lifetime of batteries. However, ultimate battery performance is still limited by capacity decay and failure due to short-circuiting via dendrite formation. Lithium is used in lithium battery electrodes, whose energy density (3862 mAh/g) is more than 10 times larger than graphite (372 mAh/g). On the other hand, lithium is more prone to grow dendrites relative to graphite, since lithium deposition is dominant over lithium intercalation (see Daniel, C., Materials and Processing for Lithium - Ion Batteries. JOM, 2008. 60).
[0005] Researchers have tried to prevent the growth of dendritic microstructures using various techniques, which are still unsuccessful. On the experimental side, several studies have tracked the influence of control parameters such as current density (see F. Orsini, A.D.P., B. Beaudoin, J. M. Tarascon, M. Trentin, N. Langenhuisen, E. D. Beer, P. Notten, In Situ Scanning Electron Microscopy ( SEM ) observation of interfaces with plastic lithium batteries. Journal of power sources, 1998. 76: p. 19-29; Graciela Gonzalez, M. R., and Elisabeth Chassaing, Transition between two dendritic growth mechanisms in electrodeposition. Physical Review E, 2008. 78 (011601)), geometry (see Monroe, C. and J. Newman, The effect of interfacial deformation on electrodeposition kinetics. Journal of the Electrochemical Society, 2004. 151 (6): p. A880-A886; Liu, X. H., et al., Lithium fiber growth on the anode in a nanowire lithium ion battery during charging. Applied Physics Letters, 2011. 98 (18)), solvent and electrolyte chemical composition (see Crowther, O. and A. C. West, Effect of electrolyte composition on lithium dendrite growth. Journal of the Electrochemical Society, 2008. 155 (11): p. A806-A811; Howlett, P. C., D. R. MacFarlane, and A. F. Hollenkamp, A sealed optical cell for the study of lithium - electrode electrolyte interfaces. Journal of Power Sources, 2003. 114 (2): p. 277-284; Schweikert, N., et al., Suppressed lithium dendrite growth in lithium batteries using ionic liquid electrolytes: Investigation by electrochemical impedance spectroscopy, scanning electron microscopy, and in situ 7 Li nuclear magnetic resonance spectroscopy. Journal of Power Sources, 2013. 228 (0): p. 237-243) and electrolyte concentration (see Brissot, C., et al., In situ concentration cartography in the neighborhood of dendrites growing in lithium/polymer - electrolyte/lithium cells. Journal of the Electrochemical Society, 1999. 146 (12): p. 4393-4400; Brissot, C., et al., Concentration measurements in lithium/polymer - electrolyte/lithium cells during cycling. Journal of Power Sources, 2001. 94 (2): p. 212-218) on dendrite formation.
[0006] Methods that have been developed to slow down dendrite formation include the use of powdered electrodes (see Kim, W. S. and W. Y. Yoon, Observation of dendritic growth on Li powder anode using optical cell. Electrochimica Acta, 2004. 50 (2-3): p. 541-545), the application of successive bipolar charge pulses (see Chen, L. L., Xue Li Zhao, Qiang Cai, Wen Bin Jiang, Zhi Yu Bipolar Pulse current method for inhibiting the formation and lithium dendrites. Acta Phys. Chim. Sin, 2006. 22 (9): p. 1155-1158), and covering lithium electrodes with adhesive lamellar block copolymers (see Stone, G. M., et al., Resolution of the Modulus versus Adhesion Dilemma in Solid Polymer Electrolytes for Rechargeable Lithium Metal Batteries. Journal of the Electrochemical Society, 2012. 159 (3): p. A222-A227).
[0007] The dynamics of dendrite growth also has been characterized to some extent. Studies gave considered evolution time (see Rosso, M., et al., Onset of dendritic growth in lithium/polymer cells. Journal of Power Sources, 2001. 97-8: p. 804-806), growth rate (see Brissot, C., et al., In situ study of dendritic growth in lithium/PEO - salt/lithium cells. Electrochimica Acta, 1998. 43 (10-11): p. 1569-1574) and electrolyte convection see Fleury, V., J. N. Chazalviel, and M. Rosso, Theory and Experimental - Evidence of Electroconvection around Electrochemical Deposits. Physical Review Letters, 1992. 68 (16): p. 2492-2495).
[0008] On the theoretical side, the few idealistic schemes have been developed to account for lithium dendrite growth have multiple deficiencies, such as dendrite shape and one dimensional cell geometry (see Chazalviel, J. N., Electrochemical Aspects of the Generation of Ramified Metallic Electrodeposits. Physical Review A, 1990. 42 (12): p. 7355-7367; Monroe, C. and J. Newman, Dendrite growth in lithium/polymer systems—A propagation model for liquid electrolytes under galvanostatic conditions. Journal of the Electrochemical Society, 2003. 150 (10): p. A1377-A1384). This has been confirmed by experimental studies on electrochemical deposition of zinc and copper (see Sagues, F., M. Q. Lopez-Salvans, and J. Claret, Growth and forms in quasi - two - dimensional electrocrystallization. Physics Reports-Review Section of Physics Letters, 2000. 337 (1-2): p. 97-115). Nonetheless, the dendrite morphology evolution mechanism is not yet understood. The microstructure study is experimentally hard and the SEM imaging of dendrites is not usually practical since the dendrites are very fragile and disassembling the cell and exposure of lithium metal to open atmosphere will not provide accurate results, for example because lithium reacts with oxygen and water vapor in the atmosphere.
[0009] Other experimental approaches for observing dendrites have been unsuccessful as well (see Brissot, C., et al., Dendritic growth mechanisms in lithium/polymer cells. Journal of Power Sources, 1999. 81: p. 925-929).
[0010] There is a need for systems and methods that allow more accurate observation of dendrite formation dynamics in more realistic device similar to current batteries.
SUMMARY OF THE INVENTION
[0011] According to one aspect, the invention features a coin cell. The coin cell comprises a pair of current collectors, one of the pair of current collectors having defined therein a sealable aperture, each current collector having a flat face, each current collector having an electrical contact accessible on an exterior surface of the coin cell; a non-conductive separator having a transparent region, the non-conductive separator having a central cavity defined therein so as to space the respective flat faces of the pair of current collectors apart by a predefined distance; a plurality of gaskets, each gasket forming an hermetic seal between the non-conductive separator and one of the pair of current collectors when assembled; a seal for the additional sealable aperture of one of the pair of current collectors; and a plurality of non-conductive clamps that hold the pair of current collectors, the non-conductive separator and the plurality of gaskets in registry when assembled.
[0012] In one embodiment, each of the pair of current collectors having a plurality of apertures defined therein, the plurality of apertures of one of the pair of current collectors defined so as to be in registry with the plurality of apertures of the other of the pair of current collectors when assembled, and the non-conductive separator having a plurality of apertures defined therein so as to be in registry with the plurality of apertures of each of the pair of current collectors when assembled.
[0013] In another embodiment, the plurality of non-conductive clamps are nuts and screws.
[0014] In yet another embodiment, the screws are fabricated from a non-conductive material.
[0015] In still another embodiment, the screws are fabricated from a conductive material and screw insulators fabricated from a non-conductive material are provided to electrically separate the screws from at least one of the pair of current collectors.
[0016] In a further embodiment, the coin cell further comprises a foil made of an electrically conductive material that is compatible with an electrolyte that is to be inserted into the coin cell, the foil positioned in electrical contact with and covering the flat face of one of the pair of current collectors.
[0017] In yet a further embodiment, the coin cell further comprises a pressure washer that makes electrical contact between the foil and the one of the pair of current collectors.
[0018] In another embodiment, the electrically conductive material and the electrolyte comprise a metal.
[0019] In yet another embodiment, the metal is lithium.
[0020] In an additional embodiment, the coin cell has cylindrical symmetry.
[0021] The foregoing and other objects, aspects, features, and advantages of the invention will become more apparent from the following description and from the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] The objects and features of the invention can be better understood with reference to the drawings described below, and the claims. The drawings are not necessarily to scale, emphasis instead generally being placed upon illustrating the principles of the invention. In the drawings, like numerals are used to indicate like parts throughout the various views.
[0023] FIG. 1A is a plan view of an anode current collector for use in the coin cell.
[0024] FIG. 1B is a cross section view from one side of the anode current collector.
[0025] FIG. 1C is a cross section view of the anode current collector from a direction 90 degrees away from the view of FIG. 1B .
[0026] FIG. 1D is a perspective view of the anode current collector.
[0027] FIG. 2A is a plan view of a cathode current collector for use in the coin cell.
[0028] FIG. 2B is a cross section view from one side of the cathode current collector.
[0029] FIG. 2C is a cross section view of the cathode current collector from a direction 90 degrees away from the view of FIG. 2B .
[0030] FIG. 2D is a perspective view of the cathode current collector.
[0031] FIG. 3A is a plan view of a transparent separator for use in the coin cell.
[0032] FIG. 3B is a cross section view from one side of the transparent separator.
[0033] FIG. 3C is a cross section view of the transparent separator from a direction 90 degrees away from the view of FIG. 3B .
[0034] FIG. 3D is a perspective view of the transparent separator.
[0035] FIG. 4A is a perspective view of a screw used to hold the coin cell together when assembled.
[0036] FIG. 4B is an end view of a screw used to hold the coin cell together when assembled.
[0037] FIG. 4C is a side view of a screw used to hold the coin cell together when assembled.
[0038] FIG. 5A is a perspective view of a nut used to hold the coin cell together when assembled.
[0039] FIG. 5B is an end view of a nut used to hold the coin cell together when assembled.
[0040] FIG. 5C is a side view of a nut used to hold the coin cell together when assembled.
[0041] FIG. 6A is a plan view of a gasket for use in the coin cell.
[0042] FIG. 6B is a cross section view from one side of the gasket.
[0043] FIG. 6C is a cross section view of the gasket from a direction 90 degrees away from the view of FIG. 6B .
[0044] FIG. 6D is a perspective view of the gasket used to hermetically seal the cell.
[0045] FIG. 7 is a perspective view of a screw insulator used to electrically insulate the screws that hold the coin cell together from at least one of the anode current collector and the cathode current collector.
[0046] FIG. 8 is a schematic diagram showing a coin cell in partially assembled configuration and an eye of a viewer looking across the coin cell from one side.
[0047] FIG. 9 is an exploded view of one embodiment of a coin cell according to principles of the invention.
[0048] FIG. 10 is an image of an assembled coin cell held in a hand to show relative scale.
[0049] FIG. 11 is a schematic diagram of a system in which experiments have been performed using the electrolytic coin cell according to principles of the invention.
[0050] FIG. 12 is an image of dendrites observed in situ using a cell that operates according to principles of the invention.
DETAILED DESCRIPTION
[0051] More direct techniques for monitoring dendrite formation with better time and spatial resolution seem essential to advance our understanding of the phenomenon of dendrite growth (see Bhattacharyya, R., et al., In situ NMR observation of the formation of metallic lithium microstructures in lithium batteries. Nature Materials, 2010. 9 (6): p. 504-510).
[0052] We now describe a coin cell that provides direct visual observation of dendrite growth and morphology in situ and offers more accurate information for understanding the behavior of lithium batteries.
[0053] The coin cell is constructed of components that are separable. In operation, the coin cell can be sealed to prevent reaction with undesired chemical species, such as water vapor and oxygen in room air. The components of the coin cell are as follows:
[0054] Current collectors are made of brass, copper or any convenient conductive metal. They can be placed in electrical communication with electrodes to transfer current. FIG. 1D is a perspective view of a first current collector, which is circular with indentation and holes. FIG. 2D is a perspective view of a second current collector, which has the same construction as the first current collector with the exception that there is a threaded aperture defined in it (for example, a 1/71 treaded hole located in the middle of it) to provide a path for electrolyte injection into the coin cell.
[0055] FIG. 3D is a perspective view of a transparent separator is provided which determines the inter-electrode distance. The transparent separator can be made of acrylic (which is easy to machine), or in alternative embodiments, from any transparent non-reactive material that is convenient. The transparent separator needs to be transparent at a location where one will observe the events that occur within the volume of the coin cell that contains an electrolyte, but otherwise could equally well be opaque elsewhere. The separator should be an insulator, rather than conductive.
[0056] FIG. 4A is a perspective view of a screw used to hold the coin cell together when assembled. In one embodiment, the screws are made of 1-71 stainless steel and are 1″ long. However, it will be understood that the screws can be made of any convenient material that is strong enough to hold the assembled cell together when operating, can be any convenient length that is sufficient to hold the assembled cell together, and can have any convenient thread. It will further be understood that if the screws are made of a non-conductive material such as nylon, the screw insulators will be redundant and may be omitted.
[0057] FIG. 5A is a perspective view of a nut used to hold the coin cell together when assembled. In one embodiment, the nuts are 1/71 nuts made of stainless steel. However, it will be understood that the nuts can be made of any convenient material that is strong enough to hold the assembled cell together when operating, and can have any thread that will mate with the screws used to hold the assembled cell together.
[0058] FIG. 6D is a perspective view of a gasket used to hermetically seal the cell. In one embodiment, the gasket is made of compliant silicone rubber. In other embodiments, other compliant materials that can be used as gaskets may be employed.
[0059] FIG. 7 is a perspective view of a screw insulator used to electrically insulate the screws that hold the coin cell together from at least one of the anode current collector and the cathode current collector.
[0060] In alternative embodiments, the assembled coin cell can be held together by clamps, such as “C” clamps applied to the opposite external (free) surfaces of the current collectors, and the apertures that provide space for the screws to pass through the various layers of components, the screws themselves, the nuts, and the screw insulators all can be omitted.
[0061] Table 1 lists the dimensions used in one embodiment of the coin cell, which dimensions are indicated in the various drawings. The angle α is 120 degrees in a preferred embodiment, but any convenient angle and any convenient number N greater than or equal to two of screws and corresponding nuts can be used.
[0000]
TABLE 1
Dimension
Size (inches)
D1
1.00
D2
0.625
D3
0.12
R1
0.40625
T1
0.1875
T2
0.1875
D4
0.4
D5
0.08
D2 + ∈
0.627
T
0.375
[0062] FIG. 8 is a schematic diagram showing a coin cell in partially assembled configuration and an eye of a viewer looking across the coin cell from one side.
[0063] FIG. 9 is an exploded view of one embodiment of a coin cell according to principles of the invention. In FIG. 9 two structures indicated as “electrodes” (one of which has an aperture that is aligned with the filling hole in the electrode shown in FIG. 2D ) and two structures indicated as “wave disk springs” are illustrated. The electrodes can be thin sheets of a metal (in one embodiment lithium metal) that is compatible with the dendrites that are intended to be studied. The “wave disk springs” are pressure washers analogous to lock washers, Belleville washers (cupped spring washers or conical washers) or spring washers and are provided to make a positive electrical contact between the respective electrode and the corresponding current collector, so that electrical continuity can be assured between the two parts. In some embodiments, the pressure washers cam be omitted if the pressure applied by the clamps is sufficient to assure electrical contact between the foil and the current collector.
[0064] As illustrated in FIG. 9 , the coin cell comprises two Li 0 foil disc electrodes (1.59 cm diameter) separated 0.32 cm by a transparent acrylic ring. The cell was filled with 1 M LiClO 4 in propylene carbonate (PC) as electrolyte. All operations were conducted in an argon-filled (H 2 O, O 2 <0.5 ppm) glovebox. Arrays of multiple such cells were simultaneously electrolyzed under galvanostatic conditions with 2 mA cm −2 pulses generated by a programmable multichannel charger. After 48 mAh (173 Coulombs) have circulated through the cells, the lengths of 45 dendrites around the cell perimeter were measured through the acrylic separator using a Leica M205FA optical microscope.
[0065] FIG. 10 is an image of an assembled coil cell held in a hand to show relative scale.
[0066] FIG. 11 is a schematic diagram of a system in which experiments have been performed using the electrolytic coin cell according to principles of the invention.
[0067] We have performed experiments in the electrolytic coin cell that provides for in situ observation of the dendrites grown on the perimeter of the disc electrodes at any stage using a microscope as illustrated schematically in FIG. 11 .
[0068] FIG. 12 is an image of dendrites observed in situ using a cell that operates according to principles of the invention.
[0069] The cell has capability for complete sealing for several months and is also detachable from an electrical source for further studies of dendrites.
DEFINITIONS
[0070] Unless otherwise explicitly recited herein, any reference to an electronic signal or an electromagnetic signal (or their equivalents) is to be understood as referring to a non-transitory electronic signal or a non-transitory electromagnetic signal.
THEORETICAL DISCUSSION
[0071] Although the theoretical description given herein is thought to be correct, the operation of the devices described and claimed herein does not depend upon the accuracy or validity of the theoretical description. That is, later theoretical developments that may explain the observed results on a basis different from the theory presented herein will not detract from the inventions described herein.
[0072] Any patent, patent application, patent application publication, journal article, book, published paper, or other publicly available material identified in the specification is hereby incorporated by reference herein in its entirety. Any material, or portion thereof, that is said to be incorporated by reference herein, but which conflicts with existing definitions, statements, or other disclosure material explicitly set forth herein is only incorporated to the extent that no conflict arises between that incorporated material and the present disclosure material. In the event of a conflict, the conflict is to be resolved in favor of the present disclosure as the preferred disclosure.
[0073] While the present invention has been particularly shown and described with reference to the preferred mode as illustrated in the drawing, it will be understood by one skilled in the art that various changes in detail may be affected therein without departing from the spirit and scope of the invention as defined by the claims. | An electrolytic coin cell that has been used to study the growth of lithium dendrites by optical observation is described. The cell makes possible observation of the growth of the dendrites in response to various applied conditions, such as applied electrical signals, chemical effects, and temporal effects in a real coin cell geometry. | 7 |
CROSS REFERENCE
[0001] This is a U.S. patent application of U.S. provisional application 60/811,925, filed Jun. 8, 2006 for a Apparatus and Method for Coil Cooling, which is hereby fully incorporated by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to a portable cooling device including an air source, such as a fan, that provides air flow, and a shroud for directing air flow from the air source at an article, particularly (a) a coil of material or (b) a non-coil metal article such a sheet, plate or ingot, having a temperature greater than the ambient room temperature. The cooling device provides cooling efficiency by directing the air from the air source at an increased velocity to a desirable area or areas on a surface of the object, thereby increasing heat transfer from the object. The cooling device shroud includes an air directing surface that influences the direction of air flow across the object in a desired pattern. Methods for preparing cooling devices and for cooling objects, particularly coils, are also described.
BACKGROUND OF THE INVENTION
[0003] In the metallurgical or metalworking field, sheets or pieces of a metal or metal alloy are processed in any number of ways that can raise the temperature of the sheet above the temperature of the ambient room temperature. The processed sheets are subsequently rolled into a coil. For example, sheets that have been treated using a cold rolling process can reach temperatures above 200° C. during the process. Heat treatments utilized to treat sheets include, but are not limited to, continuous annealing/solution heat treatment (SHT) and batch annealing. During a continuous annealing/SHT process, the sheet is uncoiled and then first passed through a furnace section and then a quench section. For some metals or alloys, the sheet comes off the quench at higher than room temperature. During batch annealing, the entire coil is placed in a furnace where it is heated to a predetermined temperature and held for a predetermined period of time, such as several hours, after which the coil is removed and allowed to cool.
[0004] Following a procedure such as, but not limited to, one of the above described procedures, it is often necessary to cool the sheet coils to ambient room temperature either as a final step prior to storing/shipping or the like, or in preparation for a subsequent step in a manufacturing sequence.
[0005] One current practice in the art is to provide forced air cooling by positioning an axial flow fan adjacent a coil and directing air flow at the coil. The air flow is generally perpendicular to the horizontal axis of the coil at the surface of the coil end, and the velocity of air is limited by the air exit velocity of the fan. When the coil has a hollow core or center, some of the air passes through the coil center and therefore does not contribute significantly to coil cooling. Furthermore, some of the air passes along the outside of the coil diameter and also does not provide efficient heat transfer.
SUMMARY OF THE INVENTION
[0006] The cooling device of the present invention comprises an air source and a shroud connected to the air source. The shroud includes an air directing surface having one or more apertures in an arrangement adapted to direct air from the air source at a predetermined area or areas on a surface of an article, such as a coil or a non-coil article, preferably of a metal or metal alloy. The shroud is utilized to direct air flow across a surface of the article to achieve more efficient cooling when compared to using the air source alone. In one embodiment, the shroud design increases the air velocity to a value greater than the velocity exit value from the air source such as a fan. In a further embodiment, the shroud includes an adaptor that allows the device to be utilized on a coil without a core, on a coil with a core, or with a coil having a mill spool which extends out beyond the plane of the coil sidewall or end. The adaptor prevents air from passing through the center of the coil.
[0007] In one embodiment, a cooling device having an air source is provided. A shroud of the device is positioned adjacent one lateral end of a coil, wherein air from the air source is directed through one or more apertures of an air directing surface of the shroud onto a surface of the coil, preferably near the inner diameter of the coil. The air flows in a gap between the surface of the coil and the air directing surface of the shroud toward the outer diameter of the coil, escaping along the end of the shroud or outer diameter of the coil. In another embodiment, the shroud air directing surface has an outer perimeter formed as an annulus, preferably having a diameter similar to the diameter of the coil. In a preferred embodiment, the adaptor of the shroud prevents air from flowing through the center of the coil.
[0008] It is, therefore, an object of the present invention to provide a cooling device that is mobile, portable, and can be easily positioned in relation to a coil in order to cool the coil for further handling or processing or a combination thereof.
[0009] A further object of the present invention is to provide a cooling device and method for utilizing the cooling device that improves heat transfer and cooling efficiency when compared to the prior art practice of providing forced air cooling by directing air from an axial flow fan at the lateral end of a coil.
[0010] Yet another object of the present invention is to provide a cooling device that is adapted to be utilized on a coil free of a core, on a coil with a core, or on a coil having a mill spool which extends out beyond the plane of an end of a coil.
[0011] Still another object of the present invention is to provide a shroud that can be easily retrofitted to an existing fan.
[0012] It is a further object of the present invention to provide a cooling device that utilizes air from an air source, increases the velocity of the air exiting the air source, and directs the air at a location near the inner diameter of a coil and subsequently along the surface of the coil.
[0013] Accordingly, one aspect of the present invention is a cooling device for use in cooling an article, comprising an air source that provides air flow, and a shroud that receives air flow from the air source and is adapted to direct the air onto a surface of the article, wherein the shroud includes a receiver that is connected to an air exhaust outlet of the air source, wherein the shroud includes an air directing surface having one or more apertures through which air flows out of the shroud, and wherein the one or more apertures have a total cross-sectional area that is less than a cross-sectional area of the air exhaust outlet.
[0014] Another aspect of the present invention is a cooling device for use in cooling a coil of material, comprising an air source that provides air flow through an air exhaust outlet, and a shroud connected to the air source that receives air from the air source exhaust outlet and is adapted to expel the air through one or more apertures of an air directing surface of the shroud, wherein the shroud includes an adaptor connected to the air directing surface of the shroud and adapted to substantially seal a core of the coil to prevent air flow through the core.
[0015] Still another aspect of the present invention is a method for cooling a coil, comprising the steps of providing a coil of material at a temperature above an ambient temperature, providing a cooling device comprising an air source that provides air flow and a shroud that receives air flow from the air source and is adapted to direct the air onto a surface of the coil, wherein the shroud includes a receiver that is connected to an air exhaust outlet of the air source, wherein the shroud includes an air directing surface having one or more apertures through which air flows out of the shroud, positioning the air directing surface of the cooling device adjacent an end of the coil, and directing air from the cooling device onto the coil end to cool the coil, wherein a velocity of the air exiting the one or more apertures is greater than a velocity of the air exiting the air exhaust outlet.
[0016] Yet another aspect of the invention is a cooling device for use in cooling an article, comprising an air source that provides air flow; and a shroud that receives air flow from the air source and is adapted to direct the air onto a surface of the article, wherein the shroud includes a receiver that is connected to an air exhaust outlet of the air source, wherein the shroud includes an air directing surface having one or more apertures through which air flows out of the shroud, wherein the air directing surface is substantially planar radially outward of an adaptor connected to the air directing surface and wherein the air directing surface is adapted to be positioned substantially parallel to a plane formed by an end of the article.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] The invention will be better understood and other features and advantages will become apparent by reading the Detailed Description of the Invention, taken together with the drawings, wherein:
[0018] FIG. 1 is a side elevational view, in partial cross-section, of one embodiment of a cooling device of the present invention positioned adjacent to the lateral end of a coil;
[0019] FIG. 2 is a partial side elevational schematic view of the cooling device of the present invention, particularly illustrating air flow through apertures of the device onto a surface of a coil;
[0020] FIG. 3 is an elevational front view of one embodiment of a shroud of a cooling device of the present invention taken through line 3 - 3 of FIG. 1 , particularly illustrating an air directing surface having apertures through which air can flow; and
[0021] FIG. 4 is a side elevational view, in partial cross-section, of one embodiment of a cooling device of the present invention having a flexible shroud, positioned adjacent to the lateral end of a coil.
DETAILED DESCRIPTION OF THE INVENTION
[0022] This description of preferred embodiments is to be read in connection with the accompanying drawings, which are part of the entire written description of this invention. In the description, corresponding reference numbers are used throughout to identify the same or functionally similar elements. Relative terms such as “horizontal,” “vertical,” “up,” “down,” “top” and “bottom” as well as derivatives thereof (e.g., “horizontally,” “downwardly,” “upwardly,” etc.) should be construed to refer to the orientation as then described or as shown in the drawing figure under discussion. These relative terms are for convenience of description and are not intended to require a particular orientation unless specifically stated as such. Terms including “inwardly” versus “outwardly,” “longitudinal” versus “lateral” and the like are to be interpreted relative to one another or relative to an axis of elongation, or other axis, as appropriate. Terms concerning attachments, coupling and the like, such as “connected” and “interconnected,” refer to a relationship wherein structures are secured or attached to one another either directly or indirectly through intervening structures, as well as both movable or rigid attachments or relationships, unless expressly described otherwise. The term “operatively connected” is such an attachment, coupling or connection that allows the pertinent structures to operate as intended by virtue of that relationship.
[0023] Referring now to the drawings, the cooling device 10 of the present invention includes an air source 20 operatively connected to a base 50 in one embodiment as shown in FIG. 1 . Air source 20 is utilized to generate or create air flow at a velocity for use by cooling device 10 . Air source 20 is generally a fan having a housing 22 , an air intake 23 , and an air exhaust outlet 24 . Air source 20 further includes a motor 25 operatively connected to housing 22 . Motor 25 is preferably an electric motor operatively connected to an electrical switch. In one embodiment, motor 25 is operable at one or more different speeds.
[0024] An impeller or propeller 26 is operatively connected to an output shaft of motor 25 . Propeller 26 includes one or more fan blades utilized to draw air into air intake 23 and expel the same through air exhaust outlet 24 . The described air source 20 is known to those of ordinary skill in the art and is commercially available from sources such as Universal Fan and Blower of Bloomfield, Ontario, Canada and Continental Fan of Buffalo, N.Y., USA. There are generally no limitations regarding the horsepower of the fan, so long as the desired air flow is provided to cool a coil 100 . A fan having a horsepower of less than 10 is utilized in this application in one embodiment to maintain ease of portability. In a preferred embodiment, an air source is utilized that is capable of maintaining relatively low flow rates at medium to high pressure without stalling or overloading, with an appropriate shroud design.
[0025] During use, a motor switch is actuated and motor 25 is energized, thereby producing rotation of propeller 26 . The rotation of propeller 26 draws air inwardly through air intake 23 and discharges the air through exhaust outlet 24 .
[0026] While the air source 20 described hereinabove is generally known in the art as an axial flow fan, any other air source such as a blower, a pump such as a rotary or centrifugal pump, a compressor, centifugal-blower or fan, tube-axial fan, or mixed flow fan, or the like can be utilized to provide a desired volume of air at a desired velocity to shroud 30 of cooling device 10 .
[0027] Shroud 30 is connected to air source 20 and receives air expelled from exhaust outlet 24 , as shown in FIG. 2 . Receiver 32 of shroud 30 extends around a perimeter of air exhaust outlet 24 and channels air through one or more internal guide vanes 33 into interior 34 of shroud 30 . The connection between receiver 32 of shroud 30 and air exhaust outlet 24 or housing 22 of air source 20 is airtight or substantially airtight in order to provide efficiency of airflow through cooling device 10 . Any means known in the art can be utilized to connect shroud 30 to air source 20 , such as a pressure fit, a latch, fasteners such as screws or nuts and bolts, adhesive, or the like, with a latch being preferred. In one embodiment, receiver 32 is an annular rim or flange conforming to the perimeter of air exhaust outlet 24 which typically has an annular opening.
[0028] Shroud 30 includes a body 36 that extends between receiver 32 to the shroud air directing surface 40 as shown in FIGS. 1 and 2 . Shroud body 36 as illustrated is formed as a frustoconical structure. A first end of body 36 , namely at receiver 32 forms a plane that is generally parallel to a plane at the second end of body 36 at air directing surface 40 . Body 36 is not limited to the frustoconical shape shown, but can have any other desired configuration so long as receiver 32 is connected to air directing surface 40 . Accordingly, body 36 can be cylindrical, rectangular, square, or the like, or combinations thereof. The function of body 36 is to transfer air received from air exhaust outlet 24 through apertures 42 of air directing surface 40 .
[0029] In a preferred embodiment, the direction of air flow 60 is changed from horizontal, i.e. the direction of air flow entering outlet 24 from air source 20 , towards a direction substantially perpendicular or perpendicular thereto, such as shown in FIG. 2 , in a gradual fashion to minimize the pressure drop and maximize the air velocity through the shroud 30 . Air flow channeling and directing is particularly important in an application utilizing an axial fan which typically does not develop high pressure. Use of guide vanes 33 attached to the shroud 30 to help direct the air flow, such as shown in FIG. 2 is preferred in one embodiment. Cap or adaptor 44 , as described hereinbelow, can also be contoured to aid in directing air flow. Known design principles of fluid dynamics can be applied to design the shape required for each application. In one embodiment, one or more air directing vanes such as spiral swirl vanes 43 , as shown in FIG. 3 , are incorporated on the coil side of the shroud 30 to increase the contact time and contact area of the cooling air with the coil 100 .
[0030] In a preferred embodiment, several straight or curvilinear vanes 43 , preferably of the same width as projection 46 , are attached to the air directing surface 40 and extend from the edge of the air exit openings towards the outer diameter or perimeter 48 and cause the air to take a curving path across the coil face. Also, the distance maintained between the coil 100 and the shroud 30 is very important in the process for cooling a coil 100 , and depends on the fan characteristics, i.e. pressure vs. flow, generally known as the fan characteristics curve. Accordingly, the distance between the coil 100 and shroud 30 , such as at air directing surface 40 , can be varied depending on the application.
[0031] In a further embodiment, shroud 30 is a substantially solid structure, but can include flexible elements in order to provide a desired air flow to a coil 100 . Portions of the shroud 30 can be formed of generally any suitable material offering a desired rigidity or form, including, but not limited to, a polymer, a rubber, or an elastomer, either thermoplastic or thermoset, such as PVC; or any suitable metal. A requirement of shroud 30 is that the material chosen must be suitable in order to withstand and substantially not deform, degrade or the like, at the temperature of the coil 100 to be cooled, for a period of time.
[0032] As stated herein above, shroud 30 includes air directing surface 40 connected to body 36 . Air directing surface 40 is adapted to be placed in close proximity to a coil 100 as illustrated in FIG. 1 in order to aid in heat transfer and cooling of the coil to a preferred temperature such as room temperature. Air directing surface 40 has a configuration adapted to direct air flow across a surface of the coil, preferably between coil lateral end surface 102 and the outer surface of air directing surface 40 .
[0033] Air directing surface 40 includes one or more apertures 42 . As illustrated in FIG. 3 , a plurality of apertures 42 are shown arranged around an adaptor 44 in the radial interior portion of air directing surface 40 . Any number of apertures can be utilized with, generally from 1 to about 16, desirably about 6 to about 10, and preferably about 8 apertures present. It is desirable in one embodiment of the present invention that the cross-sectional area of all of the apertures present on air directing surface 40 be less than the cross-sectional area of the air exhaust outlet 24 in order to provide an increase in air velocity through the apertures collectively when compared to air exhaust outlet 24 in order to provide improved heat transfer between the air and the coil, according to heat transfer theory.
[0034] In a preferred embodiment, a plurality of apertures 42 are spaced around the circumference of adaptor 44 . In this alignment, the air flowing out of apertures 42 is directed onto the interior portion of lateral end surface 102 of coil 100 adjacent to spool 104 thereof. As illustrated in FIG. 2 , air flow travels along lateral end surface 102 radially outwardly toward the outer diameter of coil 100 . The size and number of apertures are matched to the fan characteristics curve and shroud design. In one embodiment, the total area of the apertures ranges generally from about 50% to about 90%, desirably about 60% to about 70%, and preferably about 66% of the area of the air exhaust outlet 24 . The area of an imaginary annular cylinder extending between the coil end and the shroud at the outer diameter of the apertures is preferably 1 to 3 times less and most preferably 1.5 times less than the total area of the apertures. In a preferred embodiment, adaptor 44 includes projection 46 extending outwardly from air directing surface 40 and is adapted to be placed near and preferably abutted against coil 100 . Preferably, projection 46 is substantially annular, or annular with a perimeter thereof extending completely around the coil core or mill spool 104 . The diameter of the projection is dependent on the size of the core or mill spool 104 . Accordingly, air is prevented from passing through the core of coil 100 or mill spool 104 about which coil 100 is wound. Projection 46 is further adapted to allow for a portion of a coil core such as a mill spool to be situated therein, should the mill spool 104 extend beyond the end of the coil 100 .
[0035] Perimeter 48 of air directing surface 40 is preferably annular although it is to be understood that other shapes or designs can be utilized. Annular perimeter 48 is utilized as the same is complimentary to the shape of lateral end surface 102 of coil 100 which is also typically annular. In one embodiment, an annular perimeter 48 has a diameter that is about 5% less than the diameter of a coil 100 , and at a minimum, is about 66% of the distance between the coil inner diameter and the coil outer diameter. The cooling device is situated adjacent the coil in one embodiment such that the area of the imaginary annular cylinder extending between the coil and the shroud at the outer diameter of the apertures 42 is preferably about 20% to about 60% of the area of exhaust outlet 24 .
[0036] Base 50 or other suitable mount is utilized to support air source 20 and shroud 30 . The structure of base 50 is not critical, so long as the air source 20 and shroud 30 are supported and allowed to perform their intended functions. In one embodiment as illustrated in FIG. 1 , base 50 includes one or more legs interconnected by a frame 54 . In a preferred embodiment, base 50 includes one or more wheels 56 that are operatively connected to frame 54 , or leg 52 as shown in FIG. 1 . Wheels 56 of base 50 allow cooling device 10 to be portable and easily moved to a desired position in relation to a coil or other object to be cooled. Wheels, if any, are provided with a lock to prevent the fan from moving away from the coil due to pressure in a preferred embodiment. Base 50 is constructed of any suitable materials or combinations of materials including, but not limited to, metal, polymer, wood, or the like.
[0037] In one embodiment such as shown in FIG. 4 , a cooling device 210 is provided having a shroud 230 having at least a portion thereof that is flexible. When shroud body 236 or other portion of shroud 230 is flexible, on either all or a part thereof, various materials can be utilized, including, but not limited to, plastic or fabric such as fabric including ducting with a support such as a spiral-wound spring-wire, or the like.
[0038] Flexible shroud 230 includes a receiver 232 that is connected to air exhaust outlet 224 of axial fan 220 to receive air therefrom and direct air into interior 234 of shroud 230 . As described above, axial fan 220 includes an air inlet 223 , motor 225 and propeller 226 . The end of flexible shroud 230 generally opposite axial fan 220 is detachably connected to an air directing surface 240 via a locking mechanism 245 that permits quick disassembly for ease of handling. Air directing surface includes an adaptor 244 and one or more projections 246 of adaptor 244 that can be operatively attached to a spool plug component that optionally extends outwardly from the coil. The adaptor 244 can be moved towards or away from the coil to make a desired seal with the spool 104 . As also described hereinabove, air directing surface 240 includes one or more apertures 242 that direct air into the coil 100 . Air directing surface 240 can include one or more air directing vanes as described hereinabove.
[0039] Adaptor 244 in one embodiment as shown in FIG. 4 has an elongated, preferably annular, projection 246 that extends into mill spool 104 , that is also typically annular. The elongated projection 246 has a length sufficient to support air directing surface 240 on coil 100 . In a preferred embodiment, the elongated projection 246 has an outer diameter slightly less than the inner diameter of mill spool 104 for a snug or friction fit.
[0040] Adaptor 244 provides support for air directing surface 240 and can rest on mill spool 104 or otherwise be operatively connected thereto.
[0041] The flexible shroud 230 advantageously allows the cooling device 210 to be utilized on coils having different core heights above a ground surface. For example, in one embodiment, air directing surface 240 is operatively connected to a core of a coil to be cooled such as shown in FIG. 4 , with the core situated at a particular height above the ground surface due to the radius of the coil as well as the height of any object the coil is situated on, if any. Depending on the height of the air directing surface 240 operatively connected to the coil, the end of flexible shroud 230 opposite receiver 230 is moved upward or downward and subsequently connected to air directing surface 240 using locking mechanism 245 . Accordingly, depending on the height of the core above a ground surface, the outer surface of flexible shroud body 236 between receiver 232 and air directing surface 240 can have a curved appearance.
[0042] Cooling device 210 includes a base 250 that supports air source 220 . In one embodiment, base 250 includes one or more wheels 256 operatively connected to frame 254 or leg 252 such as shown in FIG. 4 . As described hereinabove, wheels 256 can be provided with a lock to prevent the fan 220 from moving away from the coil 100 .
[0043] In order to utilize cooling device 10 of the present invention, cooling device 10 is moved into a desired position in relation to a coil 100 , such as illustrated in FIGS. 1 and 2 . Preferably, projection 46 is aligned over or around spool 104 of coil 100 forming a seal to prevent air flow therethrough. Air source 20 is actuated and air flows through air exhaust outlet 24 into interior 34 of body 36 of shroud 30 . Air flows out of interior 34 through one or more apertures 42 toward lateral end surface 102 of coil 100 . Since the air flow cannot deeply penetrate lateral end surface 102 , the forced air continues to flow radially outward toward the outer diameter of coil 100 between air directing surface 40 and lateral end surface 102 . The air flow is generally perpendicular to the horizontal axis of the coil. Shroud 30 increases air velocity from the air source, thereby increasing the heat transfer. In an alternative embodiment, the power required for the air source 20 may be reduced for equivalent cooling capacity since utilization of the cooling air is more efficient. Shroud 30 and base 50 can be easily retrofitted to existing air source 20 .
[0044] Articles that can be cooled by the present invention include any material, such as a coil or a non-coil article, preferably a metal or metal alloy. Non-coil metal articles include examples such as a sheet, plate, or ingot. Sheet material utilized to form coil 100 can have any thickness. However, in general air cooling of the type desired herein is most efficient with thinner material due to the larger number of windings per coil. Air gaps and surface roughness between laps tend to provide an insulating effect. The more of these discontinuities there are, the more heat movement and thus cooling is favored in the axial direction. In a preferred embodiment, coil 100 is aluminum or an aluminum alloy. Generally any of the numerous one or more 1xxx through 9xxx series alloy articles such as, but not limited to, sheets, plates, coils, and ingots according to the Aluminum Association Designation for Wrought Aluminum Alloys can be utilized. Coil 100 preferably has a side surface 106 having a perimeter that is circular, although side surfaces of other configurations which are not circular, but are substantially circular, oval, or the like can also be utilized. As described herein, coil 100 can have a center or core comprising a spool 104 that is hollow or solid. Coil 100 can be wound upon a mill spool 104 which can be of any suitable composition such as steel, aluminum or fiber. While coil 100 can generally have any diameter, typical diameters range from about 76.2 cm (30 inches) to about 25.40 cm (100 inches), and spools typically vary between about 20.3 cm (8 inches) to about 122 cm (48 inches), but can be smaller or larger.
[0045] In accordance with the patent statutes, the best mode and preferred embodiment have been set forth, the scope of the invention is not limited thereto, but rather by the scope of the attached claims. | A cooling device including an air source, preferably a fan, that provides air flow and a shroud for directing air flow from the air source at an object, particularly a coil of material, preferably a metal or metal alloy having a temperature greater than the ambient room temperature. The cooling device provides cooling efficiency by directing the air from the air source at an increased velocity to a desirable area or areas on an end surface of the object, thereby increasing heat transfer from the object. The cooling device shroud includes an air directing surface that influences the direction of air flow across the object in a desired pattern. Methods for preparing cooling devices and for cooling objects are also described. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of U.S. patent application Ser. No. 10/802,326 filed Mar. 17, 2004, now U.S. Pat. No. 7,159,663 which issued Jan. 9, 2007.
MICROFICHE APPENDIX
Not Applicable.
TECHNICAL FIELD
The present invention relates generally to wellhead systems for the extraction of subterranean hydrocarbons and, in particular, to a hybrid wellhead system employing both threaded unions and flanged connections.
BACKGROUND OF THE INVENTION
Wellhead systems are used for the extraction of hydrocarbons from subterranean deposits. Wellhead systems include a wellhead and, optionally mounted thereto, various Christmas tree equipment (for example; casing and,tubing head spools, mandrels, hangers, connectors, and fittings). The various connections, joints and unions needed to assemble the components of the wellhead system are usually either threaded or flanged. As will be elaborated below, threaded unions are typically used for low-pressure wells where the working pressure is less than 3000 pounds per square inch (PSI), whereas flanged unions are used in high-pressure wells where the working pressure is expected to exceed 3000 PSI.
Independent screwed wellheads are well known in the art. The American Petroleum Institute (API) classifies a wellhead as an“independent screwed wellhead” if it possesses the features set out in API Specification 6 A entitled “Specification for Wellhead and Christmas Tree Equipment.” The independent screwed wellhead has independently secured heads for each tubular string supported in the well bore. The pressure within the casing is controlled by a blowout preventer (BOP) typically secured atop the wellhead. The head is said to be“independently” secured to a respective tubular string because it is not directly flanged or similarly affixed to the casing head. Independent screwed wellheads are widely used for production from low-pressure production zones because they are economical to construct and maintain. Independent screwed wellheads are typically utilized where working pressures are less than 3000 pounds per square inch (PSI). Further detail is found in U.S. Pat. No. 5,605,194 (Smith) entitled“Independent Screwed Wellhead with High Pressure Capability and Method” which provides an apt summary of the features, uses and limitations of independent screwed wellheads.
Flanged wellheads, as noted above, are employed where working pressures are expected to exceed 3000 PSI. Wellhead systems with flanged connections are frequently designed to withstand fluid pressures of 5000 or even 10,000 PSI. The downside of flanged wellheads (also known in the art as ranged wellheads) is that they are heavy, time-consuming to assemble, and expensive to construct and maintain. As noted in U.S. Pat. No. 5,605,194 (Smith), a 5000-PSI ranged wellhead may cost two to four times that of an independent screwed wellhead with a working pressure rating of 3000 PSI. While oil and gas companies prefer to employ independent screwed wellheads rather than flanged wellheads, the latter must be used for high-pressure applications. Oil and gas companies are thus faced with a tradeoff between pressure rating and cost.
U.S. Pat. No. 5,605,194 (Smith) discloses an apparatus and method for temporarily reinforcing a low-pressure independent screwed wellhead with a high-pressure casing nipple so as to give it a high-pressure capability. The casing nipple described by Smith permits high-pressure fracturing operations to be performed through an independent screwed wellhead. Fracturing operations may achieve fluid pressures in the neighborhood of 6000 PSI, which the casing nipple is able to withstand even though the wellhead is only rated for 3000 PSI.
One of the disadvantages of the Smith casing nipple and method of use is that the casing nipple must be installed prior to fracturing and then removed prior to inserting the tubing string. As persons skilled in the art will readily appreciate, the steps of installing and removing the casing nipple generally entail killing the well, resulting in uneconomical downtime for the rig and potentially reversing beneficial effects of the fracturing operation. It is thus highly desirable to provide an apparatus and method which overcomes these problems.
There therefore exists a need for a wellhead system which withstands elevated fluid pressures and permits the extraction of subterranean hydrocarbons at less cost for the wellhead equipment.
SUMMARY OF THE INVENTION
It is therefore an object of the invention to provide a hybrid wellhead system which optimally combines the high-pressure rating of a flanged wellhead with the relative ease-of-use and low cost of an independent screwed wellhead. The hybrid wellhead is easier and more economical to manufacture and assemble, minimizes rig downtime, and is nonetheless able to withstand high fluid pressures (e.g., at least 5000 PSI).
The hybrid wellhead system is capable of withstanding elevated fluid pressures when subterranean hydrocarbon formations are stimulated in a well. The hybrid wellhead system has a plurality of tubular heads, each tubular head suspending a respective tubular string in the well, the tubular heads being connected to the hybrid wellhead system by threaded unions; and a tubing head spool mounted to the wellhead system having a top end that is flanged for connection to a flow-control stack.
The invention further provides a method of installing a wellhead for stimulating a well for the extraction of hydrocarbons therefrom, where the pressure may spike above a working pressure rating of an independent screwed wellhead, the method comprising the steps of: securing each successive tubular head to the wellhead using a threaded union; and securing a flow-control stack to the wellhead using a flanged connection.
BRIEF DESCRIPTION OF THE DRAWINGS
Further features and advantages of the present invention will become apparent from the following detailed description, taken in combination with the appended drawings, in which:
FIG. 1 is a cross-sectional elevation view of a conductor assembly having a conductor window fastened with a quick-connector to a conductor pipe that is, in turn, dug into the ground;
FIG. 2 is a cross-sectional elevation view of the conductor assembly shown in FIG. 1 after a surface casing has been run in and a wellhead has been landed onto a conductor bushing;
FIG. 3 is a cross-sectional elevation view illustrating the removal of the conductor window, leaving behind the exposed wellhead;
FIG. 4 is a cross-sectional elevational view showing a drilling flange and a blowout preventer secured to the wellhead by a threaded union;
FIG. 5 is a cross-sectional elevation view of a test plug locked into place by locking pins in the drilling flange prior to retraction of the landing tool;
FIG. 6 is a cross-sectional elevational view illustrating a drill bushing locked in place inside the drilling flange;
FIG. 7 is a cross-sectional elevational view of an intermediate casing being run through the stack until an intermediate casing mandrel is landed onto the wellhead;
FIG. 8 is a cross-sectional elevational view illustrating the raising of the drilling flange and blowout preventer and the mounting of an intermediate head spool, or “B Section”, onto the wellhead and intermediate casing mandrel;
FIG. 9 is a cross-sectional elevational view showing a B Section test plug locked in place by locking pins in the drilling flange;
FIG. 10 is a cross-sectional elevational view of another drill bushing locked in place in the drilling flange;
FIG. 11 is a cross-sectional elevational view of a production casing being run through the stack until a production casing mandrel is landed in the intermediate head spool;
FIG. 12 is a cross-sectional elevational view depicting the removal of the blowout preventer and drilling flange from the intermediate head spool;
FIG. 13 is a cross-sectional elevational view of a tubing head spool secured by a nut to the intermediate head spool;
FIG. 14 is a cross-sectional elevational view of a tubing head pressure test tool inserted into the production casing for pressure-integrity testing;
FIG. 15 is a cross-sectional elevational view of slips attached to the intermediate casing to be used where the intermediate casing cannot be run to its predicted depth;
FIG. 16 is a cross-sectional elevational view of the slips seated in the casing bowl of the wellhead, showing a packing nut which is used to secure a seal plate on top of the slips;
FIG. 17 is a cross-sectional elevational view showing an intermediate head spool and drop sleeve being lowered onto the packing nut and wellhead;
FIG. 18 is a cross-sectional elevational view of the intermediate head spool secured to the wellhead with a drop sleeve above the packing nut, seal plate and slips;
FIG. 19 is a cross-sectional elevational view of a second embodiment of the intermediate casing mandrel which has been elongated to replace the drop sleeve and the slips; and
FIG. 20 is a cross-sectional elevational view of an assembled hybrid wellhead system showing a flow control stack flanged to the top of a tubing head spool, and threaded unions securing the tubing head spool to the intermediate head spool and securing the intermediate head spool to the wellhead.
It will be noted that throughout the appended drawings, like features are identified by like reference numerals.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
For the purposes of this specification, the expressions “wellhead system”, “tubular head”, “tubular string”, “mandrel”, and “threaded union” shall be construed in accordance with the definitions set forth in this paragraph. The expression “wellhead system” shall denote a wellhead (also known as a “casing head” or “surface casing head”) mounted atop a conductor assembly which is dug into the ground and which has, optionally mounted thereto, various Christmas tree equipment (for example, casing head housings, casing and tubing head spools, mandrels, hangers, connectors, and fittings). The wellhead system may also be referred to as a“stack” or as a“wellhead-stack assembly”. The expression“tubular head” shall denote a wellhead body such as a tubing head spool used to support a tubing mandrel, intermediate head spool (also known as a“B Section”) or a wellhead (also known as a casing head). The expression “tubular string” shall denote any casing or tubing, such as surface casing, intermediate casing, production casing or production tubing. The expression“mandrel” shall denote any generally annular mandrel body such as a production casing mandrel, intermediate casing mandrel or a tubing hanger (also known as a tubing mandrel or production tubing mandrel). The expression“threaded union” shall denote any threaded connection such as a nut, sometimes also referred to as a wing-nut, spanner nut, or hammer unions.
Prior to boring a hole into the earth for the extraction of subterranean hydrocarbons such as oil or natural gas, it is first necessary to“build the location” which involves removing any soil, sand, clay or gravel to the bedrock. Once the location is “built”, the next step is to “dig the cellar” which entails digging down approximately 40-60 feet, depending on bedrock conditions. The “cellar” is also known colloquially by persons skilled in the art as the “rat hole”.
As illustrated in FIG. 1 , a conductor 12 is inserted (or, in the jargon,“stuffed”) into the rat-hole that is dug into the ground or bedrock 10 . The upper portion of the conductor 12 that protrudes above ground level is referred to as a“conductor nipple” 13 . A conductor ring 14 (also known as a conductor bushing) is fitted atop the upper lip of the conductor nipple 13 . The conductor ring 14 has an upper beveled surface defining a conductor bowl 14 a.
A conductor window 16 , which has discharge ports 15 , is connected to the conductor nipple 13 via a conductor pipe quick connector 18 , which uses locking pins 19 to fasten the conductor window 16 to the conductor nipple 13 . When fully assembled, the conductor window 16 , the conductor ring 14 and the conductor 12 constitute a conductor assembly 20 . At this point, a drill string (not shown, but well known in the art) is introduced to bore a hole that is typically 600-800 feet deep with a diameter large enough to accommodate a surface casing.
As depicted in FIG. 2 , after drilling is complete, a surface casing 30 is inserted, or“run”, through the conductor assembly 20 and into the bore. The surface casing 30 is connected by threads 32 at an upper end to a wellhead 36 in accordance with the invention. The wellhead 36 has a bottom end 34 shaped to rest against the conductor bowl 14 a . The surface casing 30 is run into the bore until the bottom end 34 of the wellhead contacts the conductor bowl 14 a , as illustrated in FIG. 2 .
As shown in FIG. 2 , the surface casing 30 is a tubular string having an outer diameter less than the inner diameter of the conductor 12 , thereby defining an annular space 33 between the conductor and the surface casing. The annular space 33 serves as a passageway for the outflow of mud when the surface casing is cemented in, a step that is well known in the art. Mud flows back up through the annular space 33 and out the discharge ports 15 located in the conductor window 16 . The annular space 33 is eventually filled up with cement during the cementing stage so as to set the surface casing in place.
A wellhead 36 (also known as a“surface casing head”) in accordance with the invention is connected to the surface casing 30 by threads 32 to constitute a wellhead-surface casing assembly. The wellhead 36 has side ports 37 (also known as flow-back ports) for discharging mud during subsequent cementing operations (which will be explained below). As illustrated in FIG. 3 , the wellhead 36 also has a casing bowl 38 , which is an upwardly flared bowl-shaped portion that is configured to receive a casing mandrel, as will be further explained below. As illustrated in FIG. 2 , the wellhead 36 is connected by threads to a landing tool 39 via a landing tool adapter 39 a . The landing tool 39 is used to insert the wellhead-surface casing assembly and to guide this assembly down into the bore until the wellhead contacts the conductor bowl. The casing bowl 38 of the wellhead 36 is set as soon as cementing is complete (to minimize rig down time). Once the surface casing 30 is properly cemented into place, the landing tool 39 and landing tool adapter 39 a is unscrewed from the wellhead 36 and removed.
As depicted in FIG. 3 , the conductor window 16 is then detached from the conductor 12 by disengaging the locking pins 19 of the quick connector 18 . After the conductor window 16 has been removed, as shown, what remains is the wellhead-surface casing assembly, i.e., the wellhead 36 sitting atop the conductor ring 14 and the conductor 12 with the surface casing 30 suspended from the wellhead.
FIG. 4 depicts a drilling flange 40 in accordance with the invention, and a blowout preventer 42 , together constituting a pressure-control stack, secured to the wellhead 36 by a threaded union 44 , such as a lockdown nut or hammer union. The drilling flange 40 and blowout preventer 42 can be installed while waiting for the cement to set, further reducing rig down time. The wellhead 36 has upper pin threads for engaging box threads of the threaded union 44 . The blowout preventer (BOP) is secured to the top surface of the drilling flange 40 with a flanged connection. A metal ring gasket 41 is compressed between the drilling flange 40 and the wellhead 36 to provide a fluid-tight seal. The metal ring gasket is described in detail in the applicant's co-pending U.S. patent application Ser. No. 10/690,142 filed Oct. 21, 2003, the specification of which is incorporated herein by reference. The ring gasket ensures a fire-resistant, high-pressure seal. The drilling flange 40 also optionally has two annular grooves 41 a in which O-rings are seated for providing a backup seal between the wellhead and the drilling flange.
The drilling flange 40 further includes locking pins 46 which are located in transverse bores in the drilling flange 40 , and which are used to lock in place plugs and bushings as will be described below in more detail. The drilling flange 40 and blowout preventer 42 are mounted to the wellhead 36 in order to drill a deep bore into or adjacent to one or more subterranean hydrocarbon formation(s). But before drilling can be safely commenced, the pressure-integrity of the wellhead system, or“stack”, should be tested.
FIG. 5 illustrates the insertion of a test plug 50 in accordance with the invention for use in testing the pressure-integrity of the stack. The pressure-integrity testing is effected by plugging the stack with the test plug 50 , closing all valves and ports (including a set of pipe rams and blinds rams on the BOP) and then pressurizing the stack. The test plug is described in detail in Applicant's co-pending U.S. patent application.
As illustrated in FIG. 5 , the test plug 50 has a bull-nosed bottom portion 51 which has an annular shoulder for supporting above it a metal gauge ring 52 , an elastomeric backup seal 53 and an elastomeric cup 54 , which is preferably made of nitrile rubber, although other elastomers or polymers may be used. The cup 54 includes a pair of annular grooves 54 a into which O-rings may be seated to provide a fluid-tight seal between the cup 54 and the bull-nosed bottom portion 51 . The test plug 50 further includes a tubular extension 55 which is threaded at a bottom end to support the bull-nosed end portion 51 . A top end of the tubular extension 55 is integrally formed with an upper shoulder 56 . The upper shoulder 56 abuts an annular constriction in the drilling flange 40 as shown in FIG. 5 . When the upper shoulder 56 has abutted the annular constriction, the locking pins 46 in the drilling flange 40 are screwed inwardly to engage an upper surface of the upper shoulder 56 , thereby securing the test plug inside the stack. The upper shoulder 56 further includes a plurality of fluid passages 57 through which fluid may flow during pressurization of the stack.
The test plug 50 is inserted and retracted using a test plug landing tool 59 which is threaded to the test plug 50 inside an internally threaded socket 58 , which extends upwardly from the upper shoulder 56 . After the test plug landing tool 59 has been removed, the stack is pressurized to an estimated operating pressure. Due to the design of the test plug 50 , the pressure-integrity of the joint between the wellhead and the surface casing is tested, as well as the pressure-integrity of all the joints and seals in the stack above the wellhead.
A typical test procedure begins with shutting the BOP pipe rams for testing of the pipe rams to at least the estimated operating pressure. The test plug 50 is then locked with the locking pins 46 and the landing tool 59 is removed. The BOP blind rams are then shut and tested to at least the estimated operating pressure. If all seals and joints are observed to withstand the test pressure, the test plug can be removed to make way for the drill string.
As shown in FIG. 6 , after the pressure-integrity of the stack is confirmed, preparations for drilling are commenced. This involves the insertion of a wear bushing 60 using a wear bushing insertion tool 62 . The wear bushing insertion tool 62 includes a landing joint 64 which is used to insert the wear bushing 60 to the correct location inside the drilling flange 40 . The wear bushing insertion tool 62 also includes a bushing holder 66 threadedly connected to a bottom end of the landing joint 64 for holding the wear bushing 60 . The wear bushing 60 is landed in the drilling flange 40 , and is then locked in place by the locking pins 46 . A head 46 a of each locking pin 46 engages an annular groove 68 in the wear bushing, thereby locking the wear bushing 60 in place.
Once the wear bushing 60 is locked in place, the wear bushing insertion tool 62 is retracted, leaving the wear bushing 60 locked inside the drilling flange 40 . The stack is thus ready for drilling operations. A drill string (not illustrated, but well known in the art) is introduced into the stack so that it may rotate within the wear bushing. The wear bushing is installed to protect the casing bowl and surface casing from the deleterious effects of a phenomenon known in the art as“Kelley Whip”. With the wear bushing in place, drilling of a bore (to the intermediate casing depth) may be commenced.
The drilling rig runs the drilling string into the well bore and stops a safe distance above a cement plug. After an appropriate cement curing time, drilling resumes. When a desired depth for an intermediate casing is reached, the drilling string is removed from the well bore.
As illustrated in FIG. 7 , the intermediate casing 70 is run through the stack and into the well bore. In certain jurisdictions, industry regulations require that intermediate casing be run when exploiting a deep, high-pressure well. The intermediate casing serves to ensure that the deep production zone is isolated from porous shallower zones in the event that a production casing is ruptured.
As depicted in FIG. 7 , the intermediate casing 70 is secured and suspended in the well bore by an intermediate casing mandrel 72 . The intermediate casing mandrel 72 is threaded to the intermediate casing 70 at a lower threaded connection 71 . The intermediate casing mandrel 72 is threaded to a landing tool 74 at an upper threaded connection 73 . The intermediate casing mandrel 72 has a lower frusta-conical end 75 shaped to be seated in the casing bowl 38 of the wellhead 36 . The lower frusta-conical end 75 of the intermediate casing mandrel 72 has a pair of annular grooves 76 in which O-rings are seated to provide a fluid-tight seal between the intermediate casing mandrel and the wellhead. The intermediate casing 70 is cemented into place by flowing back mud through the side ports 37 of the wellhead 36 , in a manner well known in the art.
As illustrated in FIG. 8 , after the landing tool 74 is detached and removed from the intermediate casing mandrel 72 , the drilling flange 40 and the blowout preventer 42 are raised to accommodate an intermediate head spool 80 in accordance with the invention. The intermediate head spool 80 is secured by threaded unions between the drilling flange 40 at the top and the wellhead 36 at the bottom.
As shown in FIG. 8 , the intermediate head spool 80 has a pair of flanged side ports 81 . The intermediate head spool 80 also has a set of upper pin threads 82 for engaging a set of box threads on the threaded union 44 . A metal ring gasket, as described in the Applicant's co-pending application referenced above, is seated in an annular groove 83 atop the intermediate head spool 80 . The drilling flange 40 is secured to the intermediate head spool 80 by the threaded union 44 which compresses the metal ring gasket between the drilling flange 40 and the intermediate head spool 80 to form a fire-resistant, high-pressure seal.
As further shown in FIG. 8 , the intermediate head spool 80 also has a bowl-shaped seat 84 for seating a tubing hanger, as will be described below. Below the side ports 81 , the intermediate head spool 80 has a pair of injection ports 85 for injecting plastic injection seals 86 . Adjacent to the injection ports are test ports 87 . The intermediate head spool 80 further includes a lower annular shoulder 88 which has an annular groove 89 . The intermediate head spool 80 is secured to the wellhead 36 by a lockdown nut 90 . The top surface of the wellhead 36 has an annular groove 36 a which aligns with the annular groove 89 in the bottom surface of the intermediate head spool 80 . A metal ring gasket is located in the annular grooves 36 a , 89 and is compressed to form a fluid-tight seal when the intermediate head spool 80 is secured to the wellhead 36 . Finally, as shown in FIG. 8 and FIG. 9 , a seal ring 92 , having four annular grooves 94 for O-rings provides a spacer and a seal beneath the intermediate head spool 80 , between the top of the wellhead and the intermediate casing mandrel.
Illustrated in FIG. 9 is a“B Section test tool” 100 (also known as the intermediate head test tool) which is secured inside the stack for use in pressure-integrity testing as described above with reference to FIG. 5 . As explained, bull-nosed bottom portion 101 which has an annular shoulder for supporting above it a metal gauge ring 102 , an elastomeric backup seal 103 and an elastomeric cup 104 , which is preferably made of nitrile rubber, although other elastomers or polymers may be used. The cup 104 includes a pair of annular grooves 104 a into which O-rings may be seated to provide a fluid-tight seal between the cup 104 and the bull-nosed bottom portion 101 . The test plug 100 further includes a tubular extension 105 which is threaded at a bottom end to support the bull-nosed end portion 101 . A top end of the tubular extension 105 is integrally formed with an upper shoulder 106 . The upper shoulder 106 abuts an annular constriction in the drilling flange 40 as shown. When the upper shoulder 106 has abutted the annular constriction, the locking pins 46 in the drilling flange 40 are screwed inwardly to engage an upper surface of the upper shoulder 106 , thereby securing the test plug inside the stack. The upper shoulder 106 further includes a plurality of fluid passages 107 through which fluid may flow during pressurization of the stack.
The B section test plug 100 is inserted and retracted using the test plug landing tool 59 , which is threaded to the test plug 100 inside an internally threaded socket 108 , which extends upwardly from the upper shoulder 106 , as described above. After the test plug landing tool 109 has been removed, the stack is pressurized to at least an estimated operating pressure. Due to the design of the B section test plug 100 , the pressure-integrity of the joint between the intermediate casing and the intermediate casing mandrel (as well as the pressure-integrity of all the joints and seals above it in the stack) are pressure tested.
A typical test procedure begins with shutting the BOP pipe rams for testing of the pipe rams to the estimated operating pressure. The B section test plug 100 is then locked with the locking pins 46 and the landing tool 59 is removed. The BOP blind rams are then shut and tested to the estimated operating pressure. After a satisfactory test, the blind rams are opened and the landing tool is reinstalled. Finally, if all seals and joints are observed to withstand the estimated operating pressure, the locking pins 46 are released and the B section test plug 100 is removed.
FIG. 10 shows the installation of an intermediate wear bushing 110 in the drilling flange 40 . The intermediate wear bushing 110 is installed using an insertion tool 112 , which is very similar to the insertion tool 62 described above with reference to FIG. 6 . The insertion tool 112 includes a landing joint 114 , which is used to insert the intermediate wear bushing 110 to the correct location inside the drilling flange 40 . The insertion tool 112 also has a bushing holder 116 threadedly connected to a bottom end of the landing joint 114 for holding the intermediate wear bushing 110 . The intermediate wear bushing 110 is aligned with the drilling flange 40 and is then locked in place by the locking pins 46 . A head 46 a of each locking pin 46 engages an annular groove 118 in the wear bushing thereby locking the intermediate wear bushing 110 in place.
Once the intermediate wear bushing 110 is locked into place, the insertion tool 112 is retracted, leaving the wear bushing 110 locked inside the drilling flange 40 . The stack is thus ready for drilling operations. A drill string (not shown) is run into the stack and rotates within the intermediate wear bushing, as described above.
After the desired bore is drilled, the drill string and associated collars and wear bushing are removed from the stack. As shown in FIG. 11 , a production casing string 120 is then run and a production casing mandrel 122 is staged for cementing.
FIG. 11 illustrates how, after cement is run, the production casing mandrel 122 is landed onto the B section, or intermediate head spool 80 , using a landing tool 124 . The production casing mandrel 122 is secured by a box thread 121 to the production casing 120 . The production casing mandrel 122 is secured to the landing tool 124 by a box thread 123 . The production casing mandrel 122 has a frusta-conical bottom end 126 that sits in the bowl-shaped seat 84 of the intermediate head spool 80 . The frusta-conical bottom end 126 has a pair of annular grooves 128 in which O-rings are received for providing a fluid-tight seal between the production casing mandrel 122 and the intermediate head spool 80 .
After the production casing mandrel 122 is landed in the intermediate head spool 80 , the landing tool 124 is disconnected from the production casing mandrel and removed. Next, the drilling flange 40 and the blowout preventer 42 are removed as a unit (along with the threaded union 44 ) as illustrated in FIG. 12 . The production casing mandrel 122 sits exposed atop the remainder of the stack.
FIG. 13 depicts a tubing head spool 130 secured by a lockdown nut 140 to the intermediate head spool 80 . The tubing head spool 130 includes a pair of flanged side ports 131 and a top flange 132 . The top flange 132 has an annular groove 133 for receiving a standard metal ring gasket (not shown), which is well known in the art. The top flange 132 also has transverse bores for housing locking pins 134 . The tubing head spool 130 has a stepped central bore 130 a.
As shown in FIG. 13 , the tubing head spool 130 further includes a inner shoulder 135 which has a bowl-shaped seat 135 a . The inner shoulder 135 abuts a top surface of the production casing mandrel 122 . Below the inner shoulder 135 is a bottom annulus 136 , which includes an outer shoulder 136 a that is engaged by the threaded union 140 when the threaded union 140 is tightened. Beneath the outer shoulder 136 a is an annular groove 136 b which aligns with the matching annular groove 83 in a top of the intermediate head spool 80 . As shown in FIG. 13 , the outer shoulder 136 a abuts the top surfaces of the seal ring 92 and the intermediate head spool 80 . A metal ring gasket is seated in the annular grooves 136 b , 83 . The metal ring gasket is described in detail in Applicant's co-pending application referenced above.
The bottom annulus 136 has two injection ports 137 through which two plastic injection seals 138 are injected. The bottom annulus 136 also has a pair of test ports 139 for use in pressure-integrity testing.
FIG. 14 illustrates a tubing head test plug 150 installed inside the bore of the stack for pressure-integrity testing. Landed in the position shown, the test plug 150 permits pressure-integrity testing of the joint between the production casing 120 and the production casing mandrel 122 , as well as all the joints and seals above that joint.
The test plug 150 has a solid bull-nosed end piece 151 which has an upper annular shoulder upon which is supported a metal gauge ring 152 , an elastomeric backup seal 153 , and an elastomeric cup 154 . The gauge ring 152 , backup seal 153 and cup 154 provide a fluid-tight seal between the test plug 150 and the production casing 120 . The cup 154 includes two annular grooves 154 a in which O-rings may be seated for providing a fluid-tight seal between the bull-nosed end piece 151 and the cup 154 . At an upper portion of the bull-nosed end piece are threads for connecting to a tubular extension 155 . The tubular extension 155 has an opening 155 a through which pressurized fluid flows during pressurization of the stack. The tubular extension has a flared section 156 with three O-ring grooves 156 a . The flared section 156 has a lower beveled shoulder 157 which sits in the bowl-shaped seat 135 a of the tubing head spool 130 . A top end of the tubular extension 155 has a pin thread 158 and a sealing end section 159 for sealed connection to a Bowen union 160 .
The Bowen union 160 includes a bottom flange 161 , a Bowen adapter 162 , and a ring gasket groove 163 which aligns with the annular groove 133 in the tubing head spool 130 for receiving a standard metal ring gasket. The Bowen union 160 further includes a pair of annular grooves 164 in which O-rings are seated for providing a fluid-tight seal between the Bowen union 160 and the sealing end section 159 of the tubular extension 155 . The Bowen union 160 further includes a set of box threads 165 for engaging the threads 158 on the tubular extension 155 .
For pressure-integrity testing of the stack, the Bowen union 160 is connected to a high-pressure line (which is not shown, but is well known in the art). Pressurized fluid is pumped through the central bore of the stack, through the opening 155 a in the tubular extension 155 and into the annular space 150 a between the tubular extension 155 and the production casing mandrel 122 and production casing 120 .
After the pressure-integrity testing has been satisfactorily completed, the high-pressure line is disconnected from the Bowen union 160 and the test plug 150 and Bowen union 160 are then removed from the stack. The hybrid wellhead system is then ready for completion.
In some cases, the intermediate casing string 70 cannot be run to the desired depth because of debris or some other blockage at or near the bottom of the well bore, or because the string length was miscalculated. In that case, slips 170 are affixed to the intermediate casing 70 , as illustrated in FIG. 15 . The slips 170 are frusta-conically shaped to be seated in an upwardly flared casing bowl 38 ′ of a wellhead 36 ′. As shown, the wellhead 36 ′ is a variant of the wellhead 36 . The wellhead 36 ′ has a modified casing bowl 38 ′, i.e., the casing bowl 38 ′ provides more angle with respect to the vertical and has a longer contact surface than the standard casing bowl 38 . The casing bowl 38 ′ is thus designed to support a tubular string using the slips 170 . The casing bowl 38 ′ includes side ports 37 ′.
Ordinarily, if the intermediate casing 70 can be fully run to the desired depth, the drilling flange 40 and the BOP 42 remain installed while the intermediate casing mandrel 72 is landed, as was shown in FIG. 7 . However, as shown in FIG. 15 , to permit the attachment of the slips 170 , it is necessary to remove the drilling flange 40 and the BOP 42 .
As illustrated in FIG. 16 , the slips 170 are seated in the casing bowl 38 ′ of the wellhead 36 ′. The intermediate casing 70 is thus suspended in the well bore. An annular seal plate 172 having four annular grooves 174 for accommodating O-rings is seated on a top surface 171 of the slips 170 and on an annular ledge 171 a of the wellhead 36 ′. As illustrated, the top surface 171 and the annular ledge 171 a are not horizontally flush. Accordingly, the underside of the annular seal plate 172 has an annular recess 173 for accommodating the annular ledge 171 a.
A packing nut 176 is secured atop the annular seal plate 172 . The packing nut 176 has external threads 178 , which engage internal threads 31 ′ on an upper annular extension 35 ′ of the wellhead 36 ′. The upper annular extension 35 ′ also has external threads for meshing with a lockdown nut as will be described below.
As shown in FIG. 17 , an intermediate head spool 80 ′ (also known as a B section) is installed atop the wellhead 36 ′ and the packing nut 176 . The intermediate head spool 80 ′ is almost identical to the intermediate head spool 80 shown in FIGS. 8-14 except for the lower annular shoulder 88 ′ which further includes a lower annular protrusion 88 a ′ to accommodate the upper annular extension 35 ′ of the wellhead 36 ′.
As illustrated in FIG. 17 , the intermediate head spool 80 ′ is secured to the wellhead 36 ′ by a threaded union 90 ′. A drop sleeve 180 is inserted as a spacer between the intermediate casing 70 and the intermediate head spool 80 ′, backing against the plastic injection seals 86 and test ports 87 . The drop sleeve 180 fits beneath an annular shoulder in the intermediate head spool and above the packing nut 176 . The drop sleeve 180 has four annular grooves 182 in which O-rings are seated for providing a fluid-tight seal between the drop sleeve 180 and the intermediate casing 70 .
FIG. 18 illustrates the intermediate head spool 80 ′ secured to the wellhead 36 ′ by the threaded union 90 ′. The intermediate casing string 70 is secured and suspended in the well by the slips 170 which are seated in the casing bowl 38 ′ of the wellhead 36 ′. The annular seal plate 172 (with O-rings in the grooves 174 ) provides a seal while the packing nut 176 secures the seal plate 172 and the slips 170 to the wellhead 36 ′. The drop sleeve 180 (with four O-rings in the grooves 182 ) acts as a spacer and seal between the intermediate head spool 80 ′ and the intermediate casing 70 , above the packing nut 176 . As shown in FIG. 18 , a drilling flange 40 (with a BOP mounted thereto, but not shown) is then secured to the intermediate head spool 80 ′ using the threaded union 44 . The threaded union 44 has a box thread that engages the upper pin thread 82 on the intermediate head spool 80 ′. A metal ring gasket is seated in the annular groove 83 . Along with two adjacent O-rings, the metal ring gasket provides a fluid-tight seal between the drilling flange 40 and the intermediate head spool 80 ′.
FIG. 19 illustrates a second embodiment of the intermediate casing mandrel 72 ′ which is designed for use in conjunction with the wellhead 36 ′. The intermediate casing mandrel 72 ′ has a box thread 71 for securing and suspending the intermediate casing 70 in the well. The intermediate casing mandrel 72 ′ includes a frusta-conical bottom end 75 ′ that is contained at the same level as the slips 170 shown in FIG. 18 . The frusta-conical bottom end 75 ′ has a larger contact surface with the wellhead 36 ′, and is thus well suited for supporting a long intermediate casing string required in a particularly deep well.
As illustrated in FIG. 19 , the frusta-conical bottom end 75 ′ has three annular grooves 77 in which O-rings are seated to provide a fluid-tight seal between the intermediate casing mandrel 72 ′ and the wellhead 36 ′. The intermediate casing mandrel 72 ′ has a top end 79 that acts as a spacer, and replaces the drop sleeve 180 shown in FIG. 18 . A thinner seal plate 172 ′ and a thinner packing nut 176 ′ accommodate the top end 79 . The seal plate 172 ′ also has four annular grooves 174 in which O-rings are seated to provide a fluid-tight seal between the intermediate casing mandrel 72 ′ and the wellhead 36 ′. The plastic injection seals 85 also provide a fluid-tight seal with the top end 79 of the intermediate casing mandrel 72 ′.
The intermediate head spool 80 ′ is secured by the threaded union 90 ′ to the wellhead 36 ′. The intermediate head spool 80 ′ abuts the top end 79 of the intermediate casing mandrel 72 ′. The outer shoulder 88 ′ abuts the top of the wellhead 36 ′. The bottom annulus 88 a ′ abuts the top of the packing nut 176 ′.
FIG. 20 illustrates a completed hybrid wellhead system which includes wellhead 36 , an intermediate head spool 80 , a tubing head spool 180 , and a flow-control stack 200 . As illustrated and described above, the wellhead 36 is secured to the surface casing 30 , the intermediate casing mandrel 72 is connected to the intermediate casing 70 , and the production casing mandrel 122 is connected to the production casing 120 . The tubing head spool 180 supports a tubing hanger 182 that is locked down by locking pins 184 . The tubing hanger 182 has a box thread 188 for securing and supporting a production tubing string 190 within the production casing 120 . The tubing head spool 180 is secured to the intermediate head spool 80 by a threaded union 195 .
The flow-control stack 200 is flanged to a top flange 185 of the tubing head spool 180 . The top flange 185 includes a ring gasket groove 186 which aligns with an annular groove 202 in the flow control stack 200 for receiving a standard metal ring gasket. The flow-control stack 200 may include any one or more of a flow tee, choke, master valve or production valves. These flow-control devices are well known in the art and are not described in further detail. The tubing hanger 182 also has a pair of annular grooves 183 in which O-rings are seated for providing a fluid-tight seal between the tubing head spool 180 and the tubing hanger 182 .
FIG. 20 illustrates threaded unions for securing the intermediate head spool to the wellhead and for securing the tubing head spool to the intermediate head spool. A flanged connection is used for securing the flow-control stack to the tubing head spool, to permit a standard flow control stack to be used for hydrocarbon production. This hybrid wellhead system is capable of withstanding higher fluid pressures than independent screwed wellheads (which are typically rated at no more than 3000 PSI). The wellhead has a working pressure rating of 3000-5000 PSI. The intermediate head spool has a working pressure rating of 10,000 PSI. The tubing head spool has a working pressure rating of 10,000-15,000 PSI and higher working pressures can be accommodated, if required.
Persons skilled in the art will appreciate that other combinations of heads, fittings and components may be assembled in the manner described above to form a hybrid wellhead system. The embodiments of the invention described above are therefore intended to be exemplary only. The scope of the invention is intended to be limited solely by the scope of the appended claims. | A hybrid wellhead system is assembled using a plurality of threaded unions, such as spanner nuts or hammer unions, for securing respective tubular heads and a flanged connection for securing a flow control stack to a top of a tubing head spool. The tubing head spool is secured by a threaded union to an intermediate head spool. The intermediate head spool is secured by another threaded union to a wellhead. Each tubular head secures and suspends a tubular string in the well bore. The hybrid wellhead system is capable of withstanding higher fluid pressures than a conventional independent screwed wellhead, while providing a more economical alternative to a flanged, or ranged, wellhead system because it is less expensive to construct and faster to assemble. | 4 |
FIELD OF THE INVENTION
[0001] This invention relates generally to a novel method for disposing of drill cuttings and more particularly to the process for source identification of such cuttings and the identification of value added processes for commercializing the cuttings in an economical manner
GENERAL BACKGROUND
[0002] In the process of drilling for oil and gas large amounts of earth, rock, shell, minerals, etc., are removed from the borehole along with drilling fluids containing chemical additives. As part of the drilling process the fluids and chemicals are recycled leaving the rock, shell, minerals etc. to be disposed of in some manner. These so-called drill cuttings are processed at the well site to reduce their bulk and remove as much of the chemical residue as possible. However, in most cases the residual contaminates remain above acceptable limits for reintroduction back in the environment without further treatment. In some cases the cuttings are collected, chemically treated, and transported to landfills where they may be further treated if necessary for atmospheric decay or simply pumped into abandoned wells. In other cases the cuttings are pulverized and treated at the well site for injection back into the earth formation of the well being drilled. Most recent developments have improved the cuttings treatment process at the well site to the point that they are considered as being acceptable for reintroduction into the environment without further treatment. In the case of off shore drilling, the cutting may be simply spread over the seabed around the drill site or transported to designated sites to serve as artificial reefs. However, on land even the highest quality drill cuttings must often be transported great distances for disposal and are often treated as contaminated waste products. As the cost of transport increases and the availability of disposal sites decreases, the cost of cuttings disposal continues to spiral upwards.
[0003] Alternative methods must be found to recycle the cuttings in a way that will help pay for their transport and reduce reliance on other mineral deposits and thereby reduce energy costs.
[0004] In addition it has been found that if the cuttings have not been treated properly or disposed of in a proper manner, they may be considered as hazardous at some future date, in which case the companies who produced the cuttings originally are held responsible for the excavation and removal for treatment and disposal. Under current law once a mined or excavated material has been found to be acceptable for reintroduction into the environment and recycled by transformation by a third party into a commercial product, the original producer is no longer responsible for the material. Therefore, it is in the best interest of the oil and gas industry to find ways and means to recycle its waste materials rather than dispose of it by burial.
SUMMARY OF THE INVENTION
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] For a further understanding of the nature and objects of the present invention, reference should be made to the following detailed description taken in conjunction with the accompanying drawings, in which, like parts are given like reference numerals, and wherein:
[0006] FIG. 1
[0007] FIG. 2
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0008] One method of disposing of drill cuttings may be by converting the cuttings directly into cement. The process of cleaning and sanitizing drill cuttings in current use for disposal reduces the residual petrochemical residue and the cutting's bulk by pulverizing and drying and produces a material that closely resembles and contains most of the key elements of Portland cement.
[0009] Portland cement is an earth material extracted near Portland, Oreg., that consists primarily of Alumna, silica, lime, iron oxide, magnesium oxide, then heated in a kiln to over 2700 degrees and then pulverized. The process further includes obtaining raw materials. Generally, raw materials consisting of combinations of limestone, shells or chalk, and shale, clay, sand, or iron ore are mined from a quarry near the plant. At the quarry, primary and secondary crushers reduce the raw materials. Stone is first reduced to 5-inch size (125-mm), then to ¾-inch (19 mm). Once the raw materials arrive at the cement plant, the materials are proportioned to create cement with a specific chemical composition. Two different methods, dry and wet, are used to manufacture Portland cement. In the dry process, dry raw materials are proportioned, ground to a powder, blended together and fed to the kiln in a dry state. In the wet process, adding water to the properly proportioned raw materials forms slurry. The grinding and blending operations are then completed with the materials in slurry form. After blending, the mixture of raw materials is fed into the upper end of a tilted, rotating, cylindrical kiln. The mixture passes through the kiln at a rate controlled by the slope and rotational speed of the kiln. Burning fuel consisting of powdered coal or natural gas is forced into the lower end of the kiln. Inside the kiln, raw materials reach temperatures of 2600 F to 3000 F (1430 C to 1650 C). At 2700 F (1480 C), a series of chemical reactions causes the materials to fuse and create cement clinker-grayish-black pellets, often the size of marbles. Clinker is discharged red-hot from the lower end of the kiln and transferred to various types of coolers to lower the clinker to handling temperatures. Cooled clinker is combined with gypsum and ground into a fine gray powder. The clinker is ground so fine that nearly all of it passes through a No. 200 mesh (75 micron) sieve. This fine gray powder is Portland cement.
[0010] Blended hydraulic cements are produced by intimately blending two or more types of cementitious material. Primary blending materials are Portland cement; ground granulated blast-furnace slag, fly ash, natural pozzolans, and silica fume. These cements are commonly used in the same manner as Portland cements. Blended hydraulic cements conform to the requirements of ASTM C595 or C1157. ASTM C595 cements are as follows: Type IS-Portland blast-furnace slag cement, Type IP and Type P-portland-pozzolan cement, Type S-slag cement, Type I (PM)-pozzolan modified portland cement, and Type I (SM)-slag modified portland cement. The blast-furnace slag content of Type IS is between 25 percent and 70 percent by mass. The pozzolan content of Types IP and P is between 15 percent and 40 percent by mass of the blended cement. Type I (PM) contains less than 15 percent pozzolan. Type S contains at least 70 percent slag by mass. Type I (SM) contains less than 25 percent slag by mass. The supplementary materials in these cements are explained further on page 28. These blended cements may also be designated as air-entraining, moderate sulfate resistant, or with moderate or low heat of hydration. ASTM C1157 blended hydraulic cements include the following: Type GU-blended hydraulic cement for general construction, Type HE-high-early-strength cement, Type MS-moderate sulfate resistant cement, Type HS-high sulfate resistant cement, Type MH-moderate heat of hydration cement, and Type LH-low heat of hydration cement. These cements can also be designated for low reactivity (option R) with alkali-reactive aggregates. There are no restrictions as to the composition of the C1157 cements. The manufacturer can optimize ingredients, such as pozzolans and slags, to optimize for particular concrete properties. The most common blended cements available are Types IP and IS. The United States uses a relatively small amount of blended cement compared to countries in Europe or Asia. However, this may change with consumer demands for products with specific properties, along with environmental and energy concerns.
[0011] As seen by the above discussion of the process for making and blending cements, it is essential that the raw materials be present and blended in the proper proportions and heated to high temperatures. Since drill cuttings contain most or may be blended to contain the same materials required for cement and kilns are being used to dry the materials prior to transport, there is no reason why the system cannot be adapted to include a process for making a type of cement. At the very least separation of the various elements and grades for use in the production of other products adds value to the cuttings. Therefore, it would be beneficial that all drill-cutting elements be identified at least as to type and grade.
[0012] The method of recycling of oil and gas well drill cuttings as disclosed herein begins by identifying drill cuttings by location, the type of earth formation and earth strata level from whence extracted. The is done by tracking and tagging the cuttings being removed from the well bore by comparison to the well logging charts that are maintained throughout the drilling operation. This provides a pedigree to any particular collection of cuttings, thereby increasing the perceived value of the product as being certified to several million years old and of a particular earth material from a particular location. In some cases the cuttings can be certified as being from several thousand feet below the surface of the sea. The cutting may be tag marked by color or by inoculation with a biological identification marker.
[0013] Recyclers are now offering used materials by grade, such as reusable brick and cement blocks, as well as brick and block chips in various sizes, stone cuttings, and grindings including clay, porcelain and ceramic scrap along with graded aggregate. It has been estimated the use of recycled stone or aggregate provides a savings of up to 15% per ton. Therefore, the use of recycled materials saves money for local governments and other purchasers, creates additional business opportunities and conserves diminishing aggregate resources, saves energy and reduces the cost of disposal.
[0014] Drill cuttings can also be provided in a dried condition with grades ranging from course to powder. The material being described as an inert mineral including sand, gravel, crushed stone, slag, rock dust and powder.
[0015] Such materials are used extensively in the cement industry and more particularly with asphalt concrete, which consist primarily of aggregate. Cement and asphalt are then added as binders. Drill cuttings may be used in such cases as graded virgin aggregate for road construction. Such roads could then be certified as being million year old roads. Buildings can be certified as being built on foundations millions of years old. Walkways, cart paths, etc., can be identified by laying the cuttings according to age or earth strata level. Therefore, by traveling such paths, which may vary by color by adding pigment to the mix thereby dyeing the materials different colors, one can virtually travel back through time.
[0016] Drill cuttings' aggregate material may also be used in building recyclable stone retaining walls used for landscaping or water drainage control by mixing the material with a recycled polymer. In some cases the materials may be designed to disintegrate over time, thereby allowing the material to become part of the landscape.
[0017] Lawn ornaments, rock gardens, etc., may be enhanced through the use of certified building materials of a known age, type and exotic origin.
[0018] In accordance with current trends in manufacturing, whereby natural alternatives are sought, identifying and segregating the types of drill cuttings material certainly increases the value of any end products produced therefrom while achieving the end result of recycling the cuttings as new products or new uses for the materials.
[0019] It is therefore an object of the invention to produce a value added recycled building and construction material that is economical and energy efficient.
[0020] It is another object of the invention to save resources and reduce impact on the environment by recycling drill cuttings rather than simply disposing of them.
[0021] Because many varying and different embodiments may be made within the scope of the inventive concept herein taught, and because many modifications may be made in the embodiments herein detailed in accordance with the descriptive requirement of the law, it is to be understood that the details herein are to be interpreted as illustrative and not in any limiting sense. | A novel method for disposing of drill cuttings and more particularly to the process for source identification of such cuttings and the identification of value added processes for commercializing the cuttings in an economical manner. The method of recycling of oil and gas well drill cuttings as disclosed herein begins by identifying drill cuttings by location, type of earth formation and earth strata level from whence extracted, drying, coding and containerizing said cuttings by said grade, mineral type, extraction location, and geological age. Uses for the recycled and graded drill cuttings include graded virgin aggregate for road construction including asphaltic cement, recyclable stone retaining walls and lawn ornaments or other applications useful in landscaping or water drainage control by mixing the dried and refined cuttings with recycled polymer. | 4 |
TECHNICAL FIELD
[0001] This invention relates generally to a foldable blade and, more particularly, to a foldable blade having folding wing portions.
BACKGROUND
[0002] Blade assemblies are widely used in earth working machinery as well as other similar machines in order to push, scrape or otherwise transport earth between two remote locations. These same blade assemblies may also be used to clear snow from highways, streets and parking lots, as well as perform a host of other tasks.
[0003] Typically, blade assemblies include a replaceable cutting edge at the bottom portion of the blade and a stiffener plate at the opposing top portion of the blade. Also, conventional blade assemblies are of a fixed length typically greater than three (3) meters. This fixed length enables the blade to scrape or push a large amount of earth during each pass of the machine.
[0004] However, some blades are of such a large length that transporting the machine is of great difficulty. This is due mainly to the limited width of many highways, streets and the like. In fact, there are even many regulations, both domestically and internationally, that regulate or limit the entire width of the machine during transport. In one such known regulation, the width of the entire machine during transport is limited to no more than approximately three (3) meters. Thus, with blades over three (3) meters in length, for example, the entire blade assembly must be removed from the machine prior to transporting the machine.
[0005] The removal of the blade assembly from the machine is a very time consuming and tedious task. This can also be a very cost prohibitive procedure, especially when the machine must be transported several times depending on the location of the next work site. In any event, in order to remove the blade from the machine, several hydraulic systems, wiring harnesses and other mechanics must be disassembled, removed and stored prior to the transporting of the machine. To reattach the blade assembly to the machine, the reverse operation must be performed. After the blade is reassembled, the hydraulics as well as other components must be tested for reliability.
[0006] U.S. Pat. No. 5,638,618 to Niemela et al., issued on Jun. 17, 1997, discloses a plow with plow wings which are individually adjustable for both extension and forward angling. A hydraulic cylinder is pivotally attached to the plow wings and, when actuated, extends and forward angles the plow wings. However, during use of the plow a large load is placed upon the wings, and hence the hydraulic cylinder. This large load placed on the hydraulic cylinder may damage or even result in total failure of the hydraulic cylinder thus leading to collapse of the plow wings. This will render the plow useless and will require valuable time to repair.
[0007] The present invention is directed to overcoming one or more of the problems as set forth above.
SUMMARY OF THE INVENTION
[0008] In one aspect of the present invention, a foldable blade has a main body portion and at least one side foldable wing portion rotatably mounted to a side of the main body portion between a first position and a second position. A first locking assembly is positioned between the main body portion and the at least one side foldable wing portion and locks the at least one side foldable wing in the first position and the second position. A second locking assembly is positioned between the main body portion and the at least one side foldable wing portion and locks the at least one side foldable wing portion in the first position.
[0009] In another aspect of the present invention, a foldable blade has a main body portion and a foldable wing portion rotatably mounted, between a first position and a second position, to the main body portion. A locking mechanism is positioned between the main body portion and the foldable wing portion, and includes a first locking assembly and a second locking assembly. The foldable wing portion is rotated about the first locking assembly and locked in the first and second positions by the first locking assembly and further locked in the second position by the second locking assembly.
[0010] In still another aspect of the present invention, a method of folding and locking a foldable blade into a retracted position is provided. The method has the steps of removing a first pin from apertures of a first locking assembly and removing a second pin from apertures of a second locking assembly. A side wing of the foldable blade is then extended outward and rotated rearwardly about a pivot pin of the first locking assembly. A second set of apertures of the first locking assembly are then aligned and a pin is inserted therein.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] [0011]FIG. 1 shows a front view of the foldable blade of the present invention;
[0012] [0012]FIG. 2 shows a rear view of the foldable blade of the present invention;
[0013] [0013]FIG. 3 shows a locking mechanism of the foldable blade in a locked first position;
[0014] [0014]FIG. 4 shows a foldable wing of the foldable blade in an extended position;
[0015] [0015]FIG. 5 shows the locking mechanism in a locked second position;
[0016] [0016]FIG. 6 shows a second embodiment of the locking mechanism of the foldable blade in a locked first position;
[0017] [0017]FIG. 7 shows the foldable wing in an extended position; and
[0018] [0018]FIG. 8 shows the locking mechanism of the second embodiment in a locked second position.
DETAILED DESCRIPTION
[0019] [0019]FIG. 1 shows a foldable blade of the present invention. The foldable blade is generally depicted as reference numeral 2 and includes a main body portion 4 and opposing side foldable wing portions 6 in substantial alignment with the main body portion 4 . The foldable blade 2 also includes a main cutting edge or scraper 8 at a bottom portion of the main body portion 4 and the opposing side foldable wing portions 6 . A stiffener bar 10 is provided at an opposing top portion of the main blade portion 4 . A face 12 of the foldable blade 2 is preferably a concave shape.
[0020] [0020]FIG. 2 shows a rear view of the foldable blade 2 . In this view, a side plate 18 is shown fixed to the foldable wing portions 6 and a hitch mechanism 20 is shown mounted on the rear portion of the main body portion 4 . A locking mechanism is also shown on the rear side of the foldable blade 2 between each of the foldable wing portions 6 and the main body portion 4 . The locking mechanism includes a first locking assembly generally depicted as reference numeral 14 and a second locking assembly generally depicted as reference numeral 16 . The first locking assembly 14 is located near a top portion of the foldable blade 2 between the foldable wing portion 6 and the main body portion 4 . The second locking assembly 16 is located near a bottom portion of the foldable blade 2 also between the foldable wing portion 6 and the main body portion 4 .
[0021] It should be recognized by those of ordinary skill in the art that the first locking assembly 14 and the second locking assembly 16 may also be located at other positions between the main body portion 4 and the foldable wing portion 6 . For example, the first locking assembly 14 may be located at the bottom portion of the main body portion 4 and the foldable wing portion 6 . Also, the use of a single foldable wing portion 6 on either side of the main body portion 4 is contemplated by the present invention. In such case, it is only necessary to provide one locking mechanism, i.e., one each of the first and second locking assemblies.
[0022] [0022]FIG. 3 shows a first embodiment of the locking mechanism of the foldable blade 2 . In FIG. 3, the first locking assembly 14 of the locking mechanism is shown to include a top plate 22 and a bottom plate 24 fixed to the main body portion 4 of the foldable blade 2 . Both the top plate 22 and the bottom plate 24 include extended portions (ears) 22 a and 24 a , respectively. The first locking assembly 14 also includes an intermediate plate 26 fixed to the foldable wing portion 6 between the top plate 22 and the bottom plate 24 . The top plate 22 and the bottom plate 24 each have respectively aligned apertures 28 a , 28 b and 28 c , where the aligned apertures 28 c preferably extend through the ears 22 a and 24 a . The intermediate plate 26 also includes apertures 30 a , 30 b and 30 c which will align with the apertures 28 a , 28 b and 28 c . (Aperture 30 b of the intermediate plate 26 is shown more clearly in FIG. 5.)
[0023] A plate guide 32 having an elongated slot 34 is fixed to the foldable wing portion 6 . The shape of the plate guide 32 is preferably curved such that the elongated slot 34 is aligned with the apertures 28 a of the top plate 22 and the bottom plate 24 and the aperture 30 a of the intermediate plate 26 . A first pin 36 is positioned within the aligned apertures 28 a and 30 a and extends through the top plate 22 , the bottom plate 24 and the intermediate plate 26 . The first pin 36 also extends into the elongated slot 34 of the plate guide 32 . A bearing 38 may be positioned about the aperture 30 a of the intermediate plate 26 . In the first locked position, a second pin 40 is inserted through the apertures 28 b and 30 b thus extending through the top plate 22 , the bottom plate 24 and the intermediate plate 26 .
[0024] Still referring to FIG. 3, the second locking assembly 16 of the locking mechanism includes a recess portion 42 mounted at a bottom portion of the main body portion 4 . The recess portion 42 includes an aperture 44 located therethrough. A lock bar 46 is mounted to a bottom portion of the foldable wing portion 6 and is aligned with and engages the recess portion 42 when in a locked position. The lock bar 46 also includes an aperture 48 (FIG. 4) which is in alignment with the aperture 44 of the recess portion 42 . A third pin 50 is inserted through the apertures 44 and 48 .
[0025] [0025]FIG. 4 shows the foldable wing portion 6 in an extended position and the locking assemblies 14 and 16 in an unlocked state. In the unlocked state, the second pin 40 is disengaged from the aligned apertures 28 b and 30 b , and the third pin 50 is disengaged from the apertures 44 and 48 . The lock bar 46 is also removed from the recess 42 . The elongated slot 34 of the plate guide 32 is translated to a second position with respect to the first pin 36 .
[0026] [0026]FIG. 5 shows the first locking assembly 14 and the second locking assembly 16 in a locked second position. In this locked second position, the foldable wing portion 6 is in a retracted or folded position behind the face 12 of the foldable blade 2 . Also, the apertures 28 c located in the respective ears 22 a and 24 a of the top plate 22 and the bottom plate 24 are aligned with the aperture 30 c of the intermediate plate 26 . A locking pin 52 is inserted through the apertures 28 c and 30 c . The second pin 40 may be placed through the aligned apertures 28 b of the top plate 22 and the bottom plate 24 , while the entire foldable wing portion 6 is rotatable about the first pin 36 . The third pin 50 may be placed through the aperture 44 and extended through the recess portion 42 .
[0027] [0027]FIG. 6 shows a second embodiment of the locking mechanism of the present invention. In this embodiment, the first locking assembly 14 is the same as the first locking assembly 14 of FIGS. 3 - 5 and a discussion herein is thus omitted. The second locking assembly 16 includes the recess portion 42 and the lock bar 46 . A bolt hole 54 extends longitudinally through the lock bar 46 and is aligned with a bolt hole 56 located at a remote end of the recess portion 42 . In the locked position of FIG. 6, the lock bar 46 extends into the recess and a bolt (or pin) 58 extends through the bolt hole 54 of the lock bar 46 and into the bolt hole 56 of the recess portion 42 .
[0028] [0028]FIG. 7 shows the foldable wing portion 6 in an extended position. Much like the extended position shown in FIG. 4, the second pin 40 is disengaged from the apertures 28 b and 30 b of the first locking assembly 14 , and the elongated slot 34 of the plate guide 32 is translated to a second position with respect to the first pin 36 . In this embodiment, the bolt 58 is disengaged from the bolt hole 56 and the lock bar 46 is also removed from the recess portion 42 .
[0029] [0029]FIG. 8 shows the locking mechanism of the second embodiment in a locked second position. In this locked second position, the foldable wing portion 6 is in a retracted or folded position behind the face 12 of the foldable blade 2 . The apertures 28 c located on the respective ears 22 a and 24 a are aligned with the aperture 30 c of the intermediate plate 26 . The locking pin 52 is inserted through the apertures 28 c and 30 c . The second pin 40 may be placed through the aligned apertures 28 b of the top plate 22 and the bottom plate 24 . Also, the bolt 58 remains within the bolt hole 54 of the lock bar 46 .
[0030] Industrial Applicability
[0031] In operation, the foldable blade 2 includes foldable wing portions 6 which are capable of being retracted to a folded position for transportation of the machine and unfolded for use in scraping, pushing and transporting earth. In the unfolded position, the locking assemblies 14 and 16 are locked into a first position.
[0032] Specifically, apertures 28 b of the top plate 22 and the bottom plate 24 as well as the aperture 30 b of the intermediate plate 26 are aligned with one another. Also, a portion of the lock bar 46 is inserted within the recess portion 42 such that the aperture 44 of the recess portion 42 and the aperture 48 of the lock bar 46 are aligned with one another. To lock the foldable wing portions 6 in the unfolded position, the second pin 40 is inserted through the apertures 28 b and 30 b and the third pin 50 is inserted through the apertures 44 and 48 . In another embodiment, the bolt 58 may be bolted between the recess portion 42 and the lock bar 46 .
[0033] To unlock and fold the foldable wing portions 6 , the second pin 40 is removed from the apertures 28 b and 30 b and the third pin 50 is removed from the apertures 44 and 48 . The wing portions 6 are then extended outward such that the elongated slot 32 is translated with respect to the first pin 36 . In this manner, a portion of the lock bar 46 is removed from the recess portion 42 . The foldable wing portions 6 are then rotated about the first pin 36 until the aperture 30 c of the intermediate plate 26 is aligned with the apertures 28 c of the top plate 22 and the bottom plate 24 (located on the respective ears 22 a and 24 a ). The locking pin 52 is then inserted through the apertures 28 c and 30 c in order to lock the foldable wing portions 6 behind the main body portion 4 of the foldable blade 2 . The second pin 40 may be placed within the apertures 28 b and the third pin 50 may be placed in aperture 44 for storage.
[0034] Other aspects and features of the present invention can be obtained from a study of the drawings, the disclosure, and the appended claims. | A foldable blade having foldable wing portions for use in earth moving machinery. The foldable wing portions include a locking mechanism which enables the foldable wing portions to be locked in a folded position or an extended position. The locking mechanism is robust thus ensuring that the wing portions will be able to withstand considerable forces without collapsing during the pushing, scraping or transporting processes. The locking mechanism includes a locking pin assembly which is easy to lock and unlock, and also allows the foldable wing portions to be rotatable. | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
The present application claims priority to U.S. Provisional Patent Application Ser. No. 60/578,776, filed Jun. 10, 2004, incorporated by reference herein.
FIELD OF THE INVENTION
The present invention relates generally to multiple antenna wireless communication systems, and more particularly, to preamble training techniques for a multiple antenna communication system.
BACKGROUND OF THE INVENTION
Multiple transmit and receive antennas have been proposed to provide both increased robustness and capacity in next generation Wireless Local Area Network (WLAN) systems. The increased robustness can be achieved through techniques that exploit the spatial diversity and additional gain introduced in a system with multiple antennas. The increased capacity can be achieved in multipath fading environments with bandwidth efficient Multiple Input Multiple Output (MIMO) techniques. A multiple antenna communication system increases the data rate in a given channel bandwidth by transmitting separate data streams on multiple transmit antennas. Each receiver receives a combination of these data streams on multiple receive antennas.
In order to properly receive the different data streams, receivers in a multiple antenna communication system must acquire the channel matrix through training. This is generally achieved by using a specific training symbol, or preamble, to perform synchronization and channel estimation. It is desirable for multiple antenna communication system to co-exist with legacy single antenna communications systems (typically referred to as Single Input Single Output (SISO) systems). Thus, a legacy (single antenna) communications system must be able to interpret the preambles that are transmitted by multiple antenna communication systems. Most legacy Wireless Local Area Network (WLAN) systems based upon OFDM modulation comply with either the IEEE 802.11a or IEEE 802.11g standards (hereinafter “IEEE 802.11a/g”). Generally, the preamble signal seen by the legacy device should allow for accurate synchronization and channel estimation for the part of the packet that the legacy device needs to understand. Previous MIMO preamble formats have reused the legacy training preamble to reduce the overhead and improve efficiency. Generally, the proposed MIMO preamble formats include the legacy legacy training preamble and additional long training symbols, such that the extended MIMO preamble format includes at least one long training symbol for each transmit antenna or spatial stream.
A number of frame formats have been proposed for evolving multiple antenna communication systems, such as MIMO-OFDM systems. Existing frame formats provide inaccurate estimations for the MIMO systems, such as inaccurate power measurement or outdated frequency offset and timing offset information, or fail to provide full backwards compatibility to the legacy devices of some vendors. In one proposed MIMO frame format, each transmit antenna sequentially transmits one or more long training symbols, such that only one transmit antenna is active at a time. As the transmit antennas are switched on and off, however, the temperature of the corresponding power amplifier will increase and decrease, respectively. Generally, such heating and cooling of the power amplifier will lead to “breathing” effects that cause the transmitted signal to have a phase or magnitude offset, relative to the desired signal.
It is therefore desirable to have a continuous transmission from all transmit antennas to avoid temperature related signal “breathing.” Thus, in further proposed MIMO frame formats, orthogonality is maintained using cyclic delay diversity (CDD) or tone-interleaving across different transmit antennas. The CDD short training symbol, however, cannot measure the received signal power with sufficient accuracy. Thus, additional backoff is required in the RF chain and additional dynamic range is required in the digitization process. Likewise, the tone interleaved design is not fully backwards compatible with a number of existing 802.11a/g devices that use short training for timing synchronization or use time domain channel estimation.
A need therefore exists for a method and system for performing channel estimation and training in a MIMO-OFDM system that is compatible with current IEEE 802.11a/g standard (SISO) systems, allowing MIMO-OFDM based WLAN systems to efficiently co-exist with SISO systems. A further need exists for MIMO preamble formats and training techniques that provide improved automatic gain control.
SUMMARY OF THE INVENTION
Generally, methods and apparatus are provided for communicating data in a multiple antenna communication system having N transmit antennas. According to one aspect of the invention, a disclosed header format includes a legacy preamble having at least one legacy long training field and an extended portion having at least N additional long training fields on each of the N transmit antennas. The N additional long training fields may be tone interleaved across the N transmit antennas and are used for MIMO channel estimation. The extended portion may include a short training field for power estimation. The short training field may be tone interleaved across the N transmit antennas and have an extended duration to support beam steering.
A more complete understanding of the present invention, as well as further features and advantages of the present invention, will be obtained by reference to the following detailed description and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic block diagram of an exemplary MIMO transmitter;
FIG. 2 is a schematic block diagram of an exemplary MIMO receiver;
FIG. 3 illustrates a conventional frame format in accordance with the IEEE 802.11a/g standards;
FIG. 4 illustrates an exemplary backward compatible preamble design using CDD;
FIG. 5 illustrates the generation of a CDD signal;
FIG. 6 illustrates an alternate preamble design based on tone interleaving;
FIG. 7 illustrates a MIMO preamble design with RTS/CTS protection;
FIG. 8 illustrates a preamble design incorporating features of the present invention that is backwards compatible with 802.11a/g legacy devices;
FIG. 9 illustrates an exemplary design for the short training symbol of FIG. 8 to measure MIMO power (AGC);
FIG. 10 illustrates an exemplary architecture for generating the short training symbol of FIG. 8 at the transmitter of FIG. 1 ;
FIG. 11 illustrates an exemplary design for the first long training symbol of FIG. 8 in the exemplary two transmit branch implementation (or two spatial streams case);
FIG. 12 illustrates an exemplary design for the second long training symbol of FIG. 8 in the exemplary two transmit branch implementation (or two spatial streams case);
FIGS. 13 and 14 illustrate preamble designs incorporating features of the present invention that for exemplary three and four transmit antenna implementations, respectively;
FIG. 15 illustrates an alternate backwards compatible preamble design;
FIG. 16 illustrates an alternate preamble design incorporating features of the present invention that reduces the length of the preamble;
FIG. 17 is a schematic block diagram of a transmitter that extends the preamble formats of the present invention for SVD-MIMO;
FIG. 18 illustrates a preamble format for SVD-MIMO; and
FIG. 19 illustrates a hybrid preamble design.
DETAILED DESCRIPTION
The present invention provides preamble formats and techniques for preamble training for MIMO system. The training phase of a MIMO transmission will contain two phases. The first training phase is a legacy training phase particularly suited, for example, to WLAN OFDM legacy systems and the second phase is particularly suited to a multiple antenna system, such as a MIMO system. To overcome the problems in the prior systems, the Automatic Gain Control (AGC) of a receiver will perform one training during the first training phase and the AGC of the receiver will retrain during the second training phase. This will allow the receiver to retrain its power measurements during the MIMO phase in order to ensure accuracy, while also allowing the receiver to be backwards compatible to WLAN systems that are not MIMO based.
FIG. 1 is a schematic block diagram of a MIMO transmitter 100 . As shown in FIG. 1 , the exemplary two antenna transmitter 100 encodes the information bits received from the medium access control (MAC) layer and maps the encoded bits to different frequency tones (subcarriers) at stage 105 . For each transmit branch, the signal is then transformed to a time domain wave form by an IFFT (inverse fast Fourier transform) 115 . A guard interval (GI) of 800 nanoseconds (ns) is added in the exemplary implementation before every OFDM symbol by stage 120 and a preamble of 32 μs is added by stage 125 to complete the packet. The digital signal is then pre-processed at stage 128 and converted to an analog signal by converter 130 before the RF stage 135 transmits the signal on a corresponding antenna 140 .
FIG. 2 is a schematic block diagram of a MIMO receiver 200 . As shown in FIG. 2 , the exemplary two antenna receiver 200 processes the signal received on two receive antennas 255 - 1 and 255 - 2 at corresponding RF stages 260 - 1 , 260 - 2 . The analog signals are then converted to digital signals by corresponding converters 265 . The receiver 200 processes the preamble to detect the packet, and then extracts the frequency and timing synchronization information at synchronization stage 270 for both branches. The guard interval is removed at stage 275 . The signal is then transformed back to the frequency domain by an FFT at stage 280 . The channel estimates are obtained at stage 285 using the long training symbol. The channel estimates are applied to the demapper/decoder 290 , and the information bits are recovered.
FIG. 3 illustrates a conventional frame format 300 in accordance with the IEEE 802.11a/g standards. As shown in FIG. 3 , the frame format 300 comprises ten short training symbols, t 1 to t 10 , collectively referred to as the Short Preamble. Thereafter, there is a Long Preamble, consisting of a protective Guard Interval (GI2) and two Long Training Symbols, T 1 and T 2 . A SIGNAL field is contained in the first real OFDM symbol, and the information in the SIGNAL field is needed to transmit general parameters, such as packet length and data rate. The Short Preamble, Long Preamble and Signal field comprise a legacy header 310 . The OFDM symbols carrying the DATA follows the SIGNAL field.
The preamble includes two parts, the training part and the signal field. The training part allows the receiver 200 to perform packet detection, power measurements for automatic gain control (AGC), frequency synchronization, timing synchronization and channel estimation. The signal field is going to be transmitted in the lowest rate and gives information, for example, on data rate and packet length. In the MIMO system, the signal field should also indicate the number of spatial streams and the number of transmit antennas 140 .
The receiver 200 uses the preamble to get all the above information in the preamble. Based on this information, when the data arrives, the receiver 200 removes the GI and transforms the data into the frequency domain using FFT, de-interleaves and decodes the data.
As previously indicated, in a MIMO system, besides these functions, it is also preferred that the preamble be backwards compatible with the legacy 802.11a/g devices, i.e., the legacy device should be able to get correct information about the duration of the packet so that it can backoff correctly and does not interrupt the MIMO HT transmission.
It is noted that there are three techniques for achieving orthogonality in a multiple antenna system. In particular, orthogonality may be achieved using (i) time diversity, (ii) cyclic delay diversity (CDD), or (iii) tone interleaving (across frequency). FIG. 4 illustrates an exemplary backward compatible preamble design 400 based on CDD. As shown in FIG. 4 , the legacy short training, long training, legacy signal field and high throughput (HT) signal field are all transmitted in a CDD fashion, as discussed below in conjunction with FIG. 5 .
FIG. 5 illustrates the generation of a CDD signal by putting the last A samples of the OFDM symbol to the beginning. Different antennas have different cyclic delays. Then following the signal fields are the MIMO training fields. In this design, the legacy training fields are reused for MIMO purpose, then, only MIMO long training is needed. The MIMO long training fields are also CDD constructed such that different transmit antennas add different phase shifts to the signal.
In the embodiment of FIG. 5 , the samples on the second transmit branch are cyclically shifted and corresponding Guard Intervals (GI) are added on transmit branches Tx- 1 and Tx- 2 . As shown in FIG. 5 , such a cyclic rotation can be achieved, for example, by putting the last samples of duration D of one OFDM symbol (still without guard interval, GI) before the rest of the symbol. Then, the guard interval, reusing the last G samples (0.8 microseconds in 802.11a OFDM) from the newly created symbol (shown as A′ in FIG. 5 ), is added. This cyclic rotation is done for all OFDM symbols across the whole packet per OFDM symbol including the preambles.
It is noted that the Short Preamble in IEEE 802.11a OFDM doesn't have an explicit Guard interval, so there, the cyclic rotation should be taken across all ten Short Preamble symbols that form the Short Preamble, and no GI subsequent addition step is required. Alternatively, it can be carried out individually per each one of the ten Short Training segments (due to periodicity, there is no difference). For the Long Preamble, the rotation should take place per each one of the two Long Training Sequences or across both at the same time, again there is no difference. Then, the (long) GI should be based on the newly constructed Long Training Sequence.
The problem with the design 400 of FIG. 4 is that the AGC power measurement of the legacy short training is not accurate compared to the MIMO training and data received power. There is typically 6 dB measurement error that needs to increase the dynamic range of the A/D 265 by one bit. This not only increases the A/D cost but also increases the dynamic range of all the analog and digital circuits. It is noted that the preamble format 400 of FIG. 4 uses the first Long Preamble in the legacy header for MIMO channel estimation.
FIG. 6 illustrates an alternate preamble design 600 that reuses the legacy preamble based on tone interleaving. In this design, the preamble is not transmitted in a CDD fashion across antennas (as in FIG. 4 ) but rather, is transmitted using tone interleaving. Different tones of the legacy preamble and legacy and HT signal fields are transmitted on different transmit antennas, such that a subcarrier (tone) is active on only one transmit branch at a time. In the MIMO long training part, the tones are alternated across the antennas so that all the tones are trained with the MIMO long training and legacy long training. This design 600 solves the problem of the accuracy of power measurement. However, it is not fully backward compatible with some existing vendors using certain receiver algorithms. It is noted that the preamble format 600 of FIG. 6 uses the first Long Preamble in the legacy header for MIMO channel estimation.
If the MIMO preamble is not backward compatible, however, then MAC layer protection mechanism, such as Request-to-Send/Clear-to-Send (RTS/CTS) has to be used. If this is the case, then a dedicated MIMO preamble can be designed just to optimize the MIMO system performance. The present invention provides both backwards compatible preamble design and a preamble design with RTS/CTS.
MIMO Preamble with RTS/CTS Protection
FIG. 7 illustrates a MIMO preamble design 700 with RTS/CTS protection. As shown in FIG. 7 , the preamble format 700 includes 10 tone-interleaved short training symbols, each 0.8 μs in the exemplary embodiment, for packet detection, AGC and coarse frequency offset estimation. Then, tone-interleaved long training symbols are used for fine timing synchronization, fine frequency synchronization and channel estimation. Following the first long training symbols is the high throughput signal field. The signal field signals, for example, the number of special streams and number of antennas. Additional long training fields are then sent, if necessary. The number of long training fields equals the number of spatial streams or the number of the transmit antennas. The data is then sent after all the long training fields. The preamble format 700 of FIG. 7 is not backwards compatible (since it does not contain a legacy signal field).
Backwards Compatible Preamble Format
FIG. 8 illustrates a preamble design 800 incorporating features of the present invention that is backwards compatible with 802.11a/g legacy devices. The preamble design 800 provides a dedicated legacy portion 810 with a signal field for backward compatibility and a dedicated MIMO training portion 820 for performance of the MIMO system.
In the preamble design 800 , the transmitter 100 first transmits the legacy 802.11a/g preamble 810 using CDD. The legacy preamble 810 performs the packet detection and coarse frequency offset estimation. The results of these two functions are also going to be used in the MIMO transmission. Besides these two functions, the legacy preamble 810 is also used to perform legacy AGC, timing and frequency synchronization and channel estimation. The receiver 200 then decodes the following legacy and HT signal fields. The HT signal field is also transmitted using CDD. As shown in FIG. 8 , following the legacy and HT signal fields is a MIMO short training field 830 and then the MIMO long training fields. The MIMO short training field 830 is used only to adjust the AGC setting, and the length can be much shorter than the legacy short training field. As illustrated here, the MIMO short training field includes a 0.8 μs guard interval and a 1.6 μs training symbol for the accurate power measurement.
It is noted that the preamble format 800 of FIG. 8 does not use the first Long Preamble in the legacy header for MIMO channel estimation. The dedicated short training symbol 830 allows precise power measurement for MIMO, at the expense of higher preamble overhead (9.6 us extra). Hence, the preamble format 800 provides low dynamic range requirements (ten bit ADC).
The MIMO long training fields of FIG. 8 are transmitted on the same frequency grid as the data, as discussed below in conjunction with FIG. 11 . Thus, Frequency Domain Channel Estimation (FDE) may be performed.
The short training field 830 of FIG. 8 is constructed in a tone-interleaved fashion, as shown in FIG. 9 . FIG. 9 illustrates an exemplary design 900 for the short training symbol 830 to measure MIMO power (AGC). While an OFDM symbol with 12 tones (i.e., 0.8 us long) would be sufficient to provide accurate power across four antennas, a 24-tone OFDM symbol (i.e. 1.6 us long) provides even more accuracy, at the expense of slightly larger overhead. The populated tones are interleaved across the transmit antennas, as shown in FIG. 9 for the case of two antennas. Dashed tones are transmitted from antenna # 1, and solid tones are transmitted from antenna # 2.
Since the short training symbol 830 is only 1.6 μs long, only 24 tones are used (of 64 total available tones). The indices of those tones are all multiples of four, so that the resulting time domain signal has a period of 1.6 μs. In the exemplary two antenna case, only half of the tones are transmitted on each transmitter antenna, i.e., every other used tone is transmitted on the first antenna and the rest of tones are transmitted on the second antenna. Moreover, this short training symbol 830 can be further shortened to 0.8 μs, which only uses 12 tones, to reduce the overhead.
FIG. 10 shows the architecture for generating the short training symbol 830 of FIG. 8 at the transmitter 100 . As shown in FIG. 10 , the active dashed tones are transmitted from antenna 1 (TX- 1 ), and solid tones are transmitted from antenna 2 (TX- 2 ). For each transmit branch, the active tones are transformed to a time domain wave form by an IFFT (inverse fast Fourier transform) 1010 , the time domain signals are then converted to a serial stream at stage 1020 , and the digital signal is upconverted to an RF signal at stage 1030 prior to transmission from each antenna (TX).
The MIMO long training fields of FIG. 8 are transmitted after the short training symbol 830 . In the preamble format 800 , since the AGC is readjusted, the legacy long training field cannot be reused for the MIMO purpose. The number of long training fields is equal to the number of spatial streams or number of the transmit antennas. Each long training filed is constructed in a tone interleaved way, with the first long training symbol using even/odd tones and the second long training symbol using odd/even tones in the exemplary embodiment.
FIG. 11 illustrates an exemplary design 1100 for the first long training symbol of FIG. 8 in the exemplary two transmit branch implementation (or two spatial streams case). The exemplary design 1100 employs 48 tones. The even tones are transmitted on the first transmit antenna and the odd tones are transmitted on the second transmit antenna in the first long training field.
FIG. 12 illustrates an exemplary design 1200 for the second long training symbol of FIG. 8 in the exemplary two transmit branch implementation (or two spatial streams case). The exemplary design 1200 employs 48 tones. The odd tones are transmitted on the first transmit antenna and the even tones are transmitted on the second transmit antenna in the second long training field.
In this way, all the tones on all the transmit antennas or spatial streams are covered after all the long training fields. In the case of more transmit antennas or spatial streams, in the same long training field, different antennas transmit different tones. The tones are alternated among antennas in different training fields to ensure that all the tones are covered by the training. The MIMO long training fields are used for the fine timing synchronization, fine frequency synchronization and channel estimation.
FIGS. 13 and 14 illustrate preamble designs 1300 , 1400 , incorporating features of the present invention that for exemplary three and four transmit antenna implementations, respectively. Generally, for each additional transmit antenna (or spatial stream), the preamble format is extended to include an additional guard interval and long training symbol (comprised of two 3.2 μs long OFDM symbols).
Further Backward Compatible Designs
FIG. 15 illustrates another backward compatible preamble design 1500 . The preamble format 1500 has two parts, the legacy 1510 preamble concatenated with the MIMO training portion 1520 . The difference here is that the long training field uses only one OFDM symbol but with 128 tones in a 20 MHz band or 256 tones in a 40 MHz band (symbol time remains 6.4 us in either case). Only one such long training field (having two OFDM symbols) is needed for the exemplary two transmit antenna implementation (two such long training fields are needed for three and four transmit antenna implementations). In the preamble design 1500 , all the MIMO channels are estimated based on this one long training field. Time domain channel estimation or other frequency domain interpolation channel estimation schemes have to be used. The drawback of this kind of channel estimation scheme is the robustness of the performance. The channel estimation scheme could be sensitive to the channel delay profiles.
Generally, the preamble design 1500 reduces the preamble overhead by concatenating two 64-point OFDM symbols into one 128-point symbol. The preamble design 1500 does not include the 0.8 us guard interval, due to the two 128 point FFTs (thus requiring time domain channel estimation, which is more complex than performing Frequency Domain channel estimation (FDE)). It is noted that FDE cannot be performed since data symbols are on the 64-point frequency grid, whereas the long training symbol is on a 128-point frequency grid in the exemplary embodiment. If the data is on a 128 point FFT grid, then the 0.8 us GI is required.
In an implementation having four transmit antennas, the 128-point FFT gets replaced by a 256 point FFT and the OFDM symbol time increases to 12.8 us. This will save 2.4 us from the preamble (assuming that the data is 64 points).
FIG. 16 illustrates another preamble design 1600 incorporating features of the present invention that reduces the length of the preamble. In the preamble design 1600 , only one long training field (having two OFDM symbols) is transmitted. In this manner, only some of the tones are covered by the training, and the other tones have to be interpolated. While the performance of such a design 1600 is not robust, it could be helpful for certain applications, such as Voice over IP (VoIP), where the performance requirement is low while the packet is short.
SVD Preamble Design
FIG. 17 is a schematic block diagram of a transmitter 1700 that extends the preamble formats of the present invention for SVD-MIMO (Singular Value Decomposition MIMO). In an SVD mode, a steering matrix is applied to map the spatial streams to the transmit antennas, as shown in FIG. 17 . FIG. 17 operates in a similar manner to FIG. 1 , except for the introduction of the spatial steering matrix that varies the signal in the spatial domain.
FIG. 18 illustrates a preamble format 1800 incorporating features of the present invention for SVD-MIMO. Generally, the preamble 1800 needs more adjustment to maintain the system performance. In the preamble 1800 , the MIMO short training needs to be much longer because each tone in SVD mode has different power scaling. In the exemplary format 1800 shown in FIG. 18 , a 3.2 μs preamble is used for the AGC measurement which uses all 52 tones. The 52 tones are interleaved across all the spatial streams, and the corresponding steering matrix (from FIG. 17 ) is applied to each tone to form the training symbol that is sent on the transmit antennas. Depending on the performance requirement and channel delay profile, more than one such short training symbol may be needed. The tones in the long training field are going to be interleaved across the spatial streams first, as discussed below in conjunction with FIGS. 13 and 14 , and then the steering matrices are applied to map to the transmit antennas.
Hybrid Preamble Design
FIG. 19 illustrates a hybrid preamble design 1900 incorporating features of the present invention. The hybrid preamble design 1900 recognizes that the preamble designs discussed above in conjunction with FIGS. 4 , 13 - 16 , and 18 all have a common legacy preamble part followed by a legacy signal field and an HT signal field. Their difference lies in the following MIMO training part. Thus, the HT signal field can be used to signal the MIMO training format, as shown in FIG. 19 . For longer packets, such as associated with video transmissions, the preamble design of FIGS. 13 and 14 can be used, having a longer preamble but demonstrating better performance. For shorter packets, such as associated with VoIP, the preamble design of FIG. 16 can be used, having shorter preambles and overhead. For such a design, only one or two bits are needed in the HT signal field to signal the preamble training format, as shown in FIG. 19 .
It is to be understood that the embodiments and variations shown and described herein are merely illustrative of the principles of this invention and that various modifications may be implemented by those skilled in the art without departing from the scope and spirit of the invention. | Methods and apparatus are provided for communicating data in a multiple antenna communication system having N transmit antennas. According to one aspect of the invention, a header format includes a legacy preamble having at least one legacy long training field and an extended portion having at least N additional long training fields on each of the N transmit antennas. The N additional long training fields may be tone interleaved across the N transmit antennas and are used for MIMO channel estimation. The extended portion may include a short training field for power estimation. The short training field may be tone interleaved across the N transmit antennas and have an extended duration to support beam steering. | 7 |
[0001] This application is a continuation in part of and claims priority from U.S. provisional application 61/979,167 by same inventors James Nicholas and George Nicholas, filed Apr. 14, 2014, the disclosure of which is incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The present invention is in the field of electromagnetic anti-tipping safety device for preventing falls by users of mobile balance and mobility aids.
DISCUSSION OF RELATED ART
[0003] There is a well-recognized need to prevent, for example, falls by persons with impaired mobility and balance (“impaired persons”), including but not limited to disabled and elderly persons. Such falls by impaired individuals frequently lead to life-threatening injuries such as broken hips, legs and arms as well as head injuries. Impaired persons commonly utilize mobile balance and mobility aids such as walkers and four-point canes in an effort to maintain balance and prevent falls. A device is desirable which would enhance such balance and mobility aids so as to prevent many of the falls and related injuries that occur in spite of their use. It is known to have fixed balance and mobility aids for use by impaired persons which are attached to stationary surfaces such as walls or floors, such as grab bars or railings, to maintain balance and prevent falls. By their nature, however, such fixed balance and mobility aids are available for use only where installed or erected.
[0004] It is further known to have mobile, hand-held or hand-pushed balance and mobility aids such as walkers and four-point canes. In contrast to the fixed mobility and balance aids described above, which do not move, such mobile balance and mobility aids are carried, pushed or otherwise moved by balance-impaired persons as they move about. Impaired persons, by supporting and/or balancing their weight on such mobile devices, are often able to stand, walk and otherwise move about without losing their balance and falling. Such mobile devices do not provide the secure attachment to a stationary surface which would be provided by a fixed grab bar or railing. Impaired persons using existing mobile balance and mobility aids are nevertheless prone to falling or tipping backward, forward or sideways, despite their use of such aids. Mobility impaired persons also have difficulty in navigating a deck of maritime vessels such as cruise ships in rough weather.
BRIEF SUMMARY OF INVENTION
[0005] An electromagnetic anti-tipping device uses electromagnets to steady users and prevent falls by persons with impaired mobility and balance. The device's steadying effect is accomplished by magnetically attracting the legs and/or wheels of balance and mobility assisting apparatus (“balance and mobility aid(s)”) to a stationary surface such as a floor which is made of or covered with a magnetically responsive material. In one embodiment, the device's electromagnet attraction to the floor or other stationary surface is actuated when the operator of the device triggers the device's mechanism or sensor by grip or touch. Once actuated, and until deactivation by the user, the device's electromagnet(s) secure the legs or wheels of the balance and mobility aid to the magnetically responsive floor or other stationary surface. The electromagnets are battery-powered.
[0006] An object of the present invention is to provide a mobile balance and mobility aid that overcomes the above described disadvantages. Mobility aids are physical devices used by temporarily and permanently disabled persons as an aid to balance and mobility.
[0007] More particularly, the present invention provides in its preferred embodiment a battery powered electromagnetic mechanism by which mobile balance and mobility aids, such as walkers and four-point canes, may become securely attached to a stationary surface, generally a floor which is made of or covered with a magnetically responsive material, at any point and at the option of the user of the mobile balance and mobility device. This secure attachment occurs when the user of the mobile balance and mobility aid, by way of a grip, touch or switch-activated triggering mechanism, activates electromagnets within the mobility aid, which electromagnets cause the legs and/or wheels of the mobility aid to be attracted magnetically to the magnetically responsive floor beneath them. As long as the electromagnetic attraction is activated, the balance and mobility aid in effect becomes a fixed balance aid, in the nature of a fixed grab bar or railing.
[0008] The user of the balance aid may trigger the mobility aid's electromagnets, thereby securing the device to the stationary surface, for example a floor, whenever the user feels a loss of balance or otherwise desires the enhanced support provided by a fixed balance aid. In this manner, the invention provides a mobile balance and mobility aid that is also, at the user's option, a fixed grab bar or railing.
[0009] According to one aspect of this invention, a mechanism triggering the magnetic attraction of the mobility aid to the magnetically responsive surface or floor is located in the grips of the mobility aid, for example a walker's grips or the handle of a four-point cane. This mechanism comprises and includes a sensing pad or pads monitoring the force being exerted on the grips or handle by the user and is to be calibrated for use by the individual user of the particular mobility aid device. When the force the user exerts on the pad or pads exceeds a certain PSI as determined during the calibration process, the electromagnets are activated, effectively attaching the once mobile walker or cane securely to the floor and thereby allowing the user to apply substantially greater force to the mobility aid in order to regain balance. In this embodiment, the magnetic attraction between the mobility aid device and the magnetically attractive floor may be triggered at the user's choice and also by the user's involuntary action of tightly gripping the mobility aid device when conscious of a feeling of loss of balance or falling. As soon as the magnetic anti-tipping device is deactivated by the operator, the electromagnets become inactive and are no longer attracted to the magnetically attractive floor, in the case of a walker, enabling the operator to continue moving with the walker just as they had been before they activated the magnetic anti-tipping device.
[0010] An additional feature of this embodiment of the magnetic anti-tipping device is an electromagnetic movement compensation system whereby, if the operator begins to lose balance and in so doing partially lifts one or more legs of the, for example, walker, from magnetically attractive surface or floor before activating the magnetic anti-tipping device, the electromagnet movement compensation system will, by operation of springs and pushrods, maintain contact between the electromagnet(s) and the magnetically attractive surface or floor, until the spring and pushrod mechanism(s) reaches maximum travel, at which point it (they) will travel with the walker upwards or away from the magnetically attractive surface. As long as the operator activates the magnetic anti-tipping device by means of the mechanical or electrical activation system before the electromagnets are beyond the functioning distance from the magnetically conducting surface or floor, the magnetic anti-tipping device will attach the walker to the floor until the operator releases the activation system.
[0011] According to another aspect of this invention, a mechanism triggering the magnetic attraction of the balance and mobility aid, for example walker or four point cane, to the magnetically responsive surface or floor is an on-off static electrical switch near the grips or handle of the mobility aid. When in the “on” position, the triggering mechanism activates the electromagnets in the balance and mobility aid device, effectively transforming the device from a mobile balance and mobility aid to a fixed and stationary aid in the nature of a fixed grab bar or handrail. In this aspect of the invention, the magnetic attraction between the balance and mobility aid device and the magnetically attractive surface, for example floor, may be triggered at the user's choice, for example for the purpose of using such a device as a portable grab bar to assist with transferring to and from, for example, a bed, chair, or toilet. According to this aspect, the device's electromagnetic attraction may remain activated for the duration of the battery life of the electromagnets, according to the needs and desires of the user. Manual or automatic controls can be added to the mobility device for triggering the magnetic attraction.
Summary of the Claims
[0012] An anti-tipping mechanism is for use on a floor and includes a mobility aid having a frame. Electromagnets are mounted to the frame. The electromagnets secure and balance the frame when activated by attracting to the floor that the mobility aid is moving upon. The electromagnets are secured to the frame at a lower portion of the frame. A control has a first mode, and a second mode. The first mode deactivates the electromagnets, and the second mode activates the electromagnets. A battery that is electrically connected to the electromagnets allows for activating the electromagnets.
[0013] The anti-tipping mechanism also optionally has a spring that provides a suspension to the electromagnet. The electromagnet contacts with the floor when a portion of the mobility aid is lifted above the floor. The third mode selectively activates the electromagnets. A tipping sensor is configured to sense tipping of the mobility aid. The electromagnet is configured to activate when the tipping sensor senses tipping of the mobility aid. A pair of wheels can be connected to the lower portion of the frame. The wheels provide a rolling movement for the user. The mobility aid can be a mobility scooter or a walker.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 is an isometric view of a prior art walker without electromagnetic anti-tipping safety device.
[0015] FIG. 2 is an exploded view of a walker with one embodiment of the electromagnetic anti-tipping safety device.
[0016] FIG. 3 is an isometric view of a walker with one embodiment of the electromagnetic anti-tipping safety device.
[0017] FIG. 4 is an isometric view of the electromagnet walker movement compensation system.
[0018] FIG. 5 is an exploded side view of the front leg electromagnet walker movement compensation system.
[0019] FIG. 6 is an exploded isometric view of the front leg electromagnet walker movement compensation system.
[0020] FIG. 7 is an unexploded alternate position view of the electromagnet walker movement compensation system.
[0021] FIG. 8 is an isometric view of the control panel of the electromagnet walker movement compensation system.
[0022] FIG. 9 is an isometric view showing an unexploded view of a mobility scooter with the electromagnetic anti-tipping safety device attached.
[0023] FIG. 10 is an isometric right side view showing an unexploded view of a mobility scooter with the electromagnetic anti-tipping safety device attached.
[0024] FIG. 11 is an isometric left side view showing an unexploded view of a mobility scooter with the magnetic anti-tipping safety device attached.
[0025] FIG. 12 shows an exploded view of a mobility scooter with the magnetic anti-tipping safety device attached.
[0026] FIG. 13 is a four point cane with two regular points and two electromagnetic points.
[0027] FIG. 14 is a shower seat with four electromagnetic points.
[0028] The following callout list of elements can be a useful guide in referencing the element numbers of the drawings.
8 Electromagnet 10 Pushrod 12 Spring 14 Sleeve 15 Frame 16 Wheels 17 Flat Portion Of Frame 18 CPU Battery Pack 20 Pressure Sensing Electric Pad 22 Low Friction Skid 24 Control Panel For The Magnetic Anti-Tipping Device 30 Switch 32 Speaker 34 Light 36 Battery Level Indicator 38 Conducting Surface Floor 41 Tipping Sensor 42 Tilt Sensor 43 Accelerometer 44 Processor 52 Mobility Scooter
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0050] A general example of a prior-art walker-type balance and mobility aid device is shown in FIG. 1 . Such walkers generally consist of a metal tubular frame with four legs and handle bars at the top of the sides of the frame. The user typically stands and moves within the frame, holding onto the handles for balance and weight support. Such walkers may have wheels on the front two legs and skids on the rear two legs. Alternatively, walkers may have wheels on the ends of all four legs, or skids on all four legs. The user pushes and/or lifts the walker in front of him or her as he or she moves. Other examples of prior art balance and mobility aids are: the four-point cane; motorized “scooter,” or small, three- or four-wheeled battery-powered, motorized vehicle with seat and handlebars; a framed and raised toilet seat, which stands on four legs; and bench or seat placed inside a tub or shower for use while bathing.
[0051] A simple, efficient magnetic anti-tipping device is provided as a safety mechanism intended to prevent users of balance and mobility aids, for example those identified above, from “tipping over” and falling while using such aids. Once triggered, this safety mechanism operates by magnetically attracting the balance and mobility device to a stationary surface, generally a floor which is made of or covered with a magnetically responsive material, at the option of the user of the mobile balance and mobility device. One example of a magnetically responsive material is a steel deck of a cruise ship.
[0052] In FIGS. 2 and 3 , one embodiment of the magnetic anti-tipping safety device is depicted as mounted on the front leg of a walker-type balance and mobility aid. FIG. 2 presents an exploded view of the elements and features of this embodiment. As seen in FIG. 2 , a total of four electromagnets 8 can be used for retaining four corners of the frame of a mobility aid. FIG. 3 shows an unexploded view thereof. This embodiment features an electromagnet movement compensation system, also shown at FIGS. 5 , 6 , allowing the electromagnet 8 to stay in contact with the conducting surface floor 38 in the event that the walker's wheels or legs lift slightly from the floor as the user begins to lose balance, before the magnetic anti-tipping system is activated. The spring 12 holds the electromagnet 8 close to the conducting surface, here the floor 38 , allowing the electromagnet 8 to travel downwards to a certain degree so as to maintain a working distance to the magnetically attractive surface. The spring 12 provides a suspension for the electromagnet 8 . The suspension can be dampened as necessary for improved mechanical control.
[0053] The electromagnets' attractive force to the magnetically attractive surface, for example floor, diminishes quickly in relation to their distance from each other. The low friction skid 22 is attached to the bottom of the electromagnet to aid in preventing the electromagnet from catching on uneven surfaces as it moves in the forward, reverse and sideways directions.
[0054] Operation of the magnetic anti-tipping device includes a pressure sensing electric pad 20 , which interacts with the CPU/battery pack 18 . Preferably, the pressure sensing electric pad 20 activates the electromagnet when the pressure sensing electric pad 20 is not sensing pressure. The tipping sensor can include a pressure sensor pad 20 which is a mechanical switch, with an accelerometer which can be an electronic component soldered to a printed circuit board, and a tilt sensor which can also be an electronic component soldered to a circuit board. The pressure sensing electric pad 20 can operate mechanically, or using capacitance sensor technology.
[0055] Operation of the magnetic anti-tipping device is not limited to the pressure sensing pad 20 but includes any kind of interaction, mechanically or electrically, that will activate and deactivate the electromagnets at the election of the user. The control panel for the magnetic anti-tipping device 24 is also depicted in detail at FIG. 8 and described below. The wheels 16 are components of the prior art walker mobile balance and mobility aid.
[0056] FIG. 4 shows an unexploded view of the electromagnet movement compensation system. FIGS. 5 , 6 both depict the internal workings of the electromagnet movement compensation system. FIG. 5 shows a neutral position of the spring when the spring is at full extension and providing the push rod 10 a full extension. The full extension pushes and extends the push rod 10 so that the electromagnet 8 extends beyond one diameter of the wheel 16 . As seen in FIG. 6 , the sleeve 14 can be mounted to a flat portion 17 of the frame 15 .
[0057] This system consists of a spring 12 to hold the electromagnet 8 on the conducting surface 38 , a push rod 10 to translate the force of the spring to the electromagnet 8 , and a sleeve 14 to house the spring 12 and pushrod 10 and attach the system to the prior art. The sleeve is a housing that can be formed of a metal tubular member and optionally has a pair of mounting holes to allow mounting to a mobility aid such as a walker or scooter. The sleeve 14 can be mounted to a frame of the mobility aid device. The sleeve can be made as a rectangular cross-section member or the circular cross-section member, as seen in the drawings. The sleeve may also include a bracket for mounting the sleeve to the frame of the mobility aid device. The wheels 16 are components of the prior art walker, which is a balance and mobility device. FIG. 7 depicts an unexploded, alternate position view of the electromagnet movement compensation system.
[0058] FIG. 8 depicts the control panel for the magnetic anti-tipping device. The control panel has a switch 30 allowing the user to statically leave the electromagnets in an active state in the event that the user wants the balance and mobility device, such as a walker or four-point cane, to become a static, fixed object that can be used, for example, as a grab bar or railing. Also on the control panel is a battery level indicator 36 showing the current power level of the CPU/battery pack 18 . Emergency indicators including a speaker 32 and a light 34 alert the user of a low voltage condition of the anti-tipping device. A speaker 32 will audibly alert the user to the low voltage condition of the magnetic anti-tipping device. A light 34 will visually alert the user to the low voltage condition of the magnetic anti-tipping device.
[0059] In FIGS. 9-12 , in unexploded and exploded views, an alternative embodiment of the magnetic anti-tipping safety device is depicted in its application to mobility scooters, or any type of electrically driven wheeled vehicle used for the purpose of transporting impaired persons. The electronic movement compensation system is depicted in this embodiment as attached to the rear end of a mobility scooter 52 resting on a magnetically conducting surface, or floor 38 which can be made of sheet metal such as the deck of a cruise ship. The magnetically conducting surface could be coated with a paint, an epoxy or a nonslip surface for example. The mobility scooter 52 has a frame that the magnetic anti-tipping safety device can be mounted to.
[0060] A variety of different modes can be implemented using this electromagnetic stability system. The switch 30 allows selection of a first mode which is the deactivated state, or off state when the user may be moving quickly and does not want to be hindered by the electromagnets magnets. In a second mode, an active state allows the frame to remain static for user to have the electromagnets on. Because the switch is located near the end of the user on the frame, the switch 30 can be activated when the user requires additional stability. The switch can be a momentary switch or a toggle switch.
[0061] An optional third mode is a sensor tipping mode that provides a tipping sensor 41 implemented by incorporating a tilt sensor 42 or accelerometer 43 or both to provide an activation of the electromagnetic stability system when the tilt sensor 42 or accelerometer 43 or both reach a certain preset amount. A processor 44 can receive a signal from a tilt sensor 42 or an accelerometer 43 . For example, if a user is on a ship that is listing by a certain number of degrees, the tilt sensor 42 can activate the electromagnets before the user loses balance. The sensor tipping mode can also assist a user in case the frame of the mobility aid device suffers sudden instability due to a collision. In case of collision, the processor 44 can receive a signal from the accelerometer 43 that indicates that the electromagnets 8 of the electromagnetic stability system should be activated. The third mode can be activated by a separate switch, or by the main switch 30 .
[0062] The processor can be configured to analyze the data from the combination of the tilt sensor 42 with the accelerometer 43 so as to initiate automatic activation of the electromagnets only when sudden tilting is detected. Sudden tilting occurs when the tilt sensor 42 and the accelerometer 43 both sense a value beyond a preset limit. The tilt sensor can be set to 10° and the accelerometer can also have a preset value. The tilt sensor can have double axis in both the forward and sideways direction so as to output a single tilt value. The tilt sensor, or pair of tilt sensors and the accelerometer or pair of accelerometers can be mounted with the processor on a printed circuit board. Preferably, the printed circuit board would be housed on an electronic housing that is mounted to the frame. The pair of tilt sensors and the pair of accelerometers both output a continuous stream of data to the processor.
[0063] The tipping sensor can include the pressure sensor pad 20 as a mechanical switch, an accelerometer as an electronic component, and also a tilt sensor as an electronic component. The combination of three sensors to form the tipping sensor potentially allows a processor to have a very accurate tipping sensing. The processor may also have a memory that has preprogrammed frame physics located within the processor. The tilt sensor could be combined with the pressure sensor pad 20 so that one or both are required for activation of the electromagnet. Having all three sensors to form the tipping sensor provides for enhanced fall protection. The pressure sensor pad 20 can be formed as a curved sheet of metal that has a capacitance sensing function. The curve of the pressure sensor pad 20 can be conformed to a pair of handles of a walker and could also be conformed to a steering wheel of a mobility scooter 52 for example. The pressure sensor pad 20 is preferably wired to the processor 44 in an electrical circuit.
[0064] The mobility aid means is preferably selected from the group of: a four point cane, a walker having wheels, a walker without wheels, a walker having pivoting wheels, a mobility scooter, a shower seat, a toilet seat frame, and a mobile grab bar. The mobile grab bar can be formed as a walker. The toilet seat frame can also be made as a walker.
[0065] The above description is provided to enable a person skilled in the art to practice the various embodiments described. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the principles defined herein may be applied to other embodiments. Thus, the appended claims are not intended to be limited to the embodiments shown herein, but are to be accorded the full scope consistent with the language in the claims with reference to an element in the singular is not intended to mean “one and only one” unless specifically so stated, but rather “one or more.” All structural and functional equivalents to the elements of the various embodiments described throughout this disclosure that are known or later come to be known to those of ordinary skill in the art are expressly incorporated herein by reference and are intended to be encompassed by the claims. Moreover, nothing disclosed herein is intended to be dedicated to the public regardless of whether such disclosure is explicitly recited in the claims. No claim element is to be construed under the provisions of 35 U.S.C. section 112, paragraph 6, unless the element is expressly recited using the phrase “means for” or, in the case of a method claim, the element is recited using the phrase “step for.” The scope of protection is limited solely by the claims that now follow. The scope is intended to be as broad as reasonably consistent with the language that is used in the claims and to encompass all structural and functional equivalents. The mechanism could be reconstructed using a different system than the system identified and described as the electromagnetic movement compensation system and still accomplish the same goal, and is therefore covered within the scope of this invention. | An electromagnetic anti-tipping device uses electromagnets to steady users and prevent falls by persons with impaired mobility and balance. The device's steadying effect is accomplished by magnetically attracting the legs and/or wheels of balance and mobility assisting apparatus (“balance and mobility aid(s)”) to a stationary surface such as a floor which is made of or covered with a magnetically responsive material. In one embodiment, the device's electromagnet attraction to the floor or other stationary surface is actuated when the operator of the device triggers the device's mechanism or sensor by grip or touch. Once actuated, and until deactivation by the user, the device's electromagnet(s) secure the legs or wheels of the balance and mobility aid to the magnetically responsive floor or other stationary surface. The electromagnets are battery-powered. | 1 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is based upon and claims the benefit of priority from U.S. Provisional Application Ser. No. 60/840,084 filed Aug. 25, 2006, the entire contents of which are incorporated by reference herein.
TECHNICAL FIELD
[0002] This disclosure relates to wastewater treatment methods and systems that remove organic and inorganic pollutants captured in the purge stream from air pollution control equipment.
BACKGROUND
[0003] Coal-fired power plants continue to produce a significant proportion of the electricity requirements for the United States. The combustion and gasification of coal is widely recognized as a significant environmental issue due to the potential release of hazardous pollutants. As a consequence, air quality standards continue to tighten. This results in the implementation of scrubbers for emissions control, most notably sulfur dioxide (SO 2 ), from coal-fired power plants.
[0004] Wet scrubber technology with lime slurry/limestone is a proven and commercially established process for flue gas emissions control, particularly SO 2 removal, from coal-fired power plants.
[0005] Wet scrubbers are usually designed with 80 to 95% efficiency of SO 2 removal. However, facilities often use additives such as magnesium-enhanced lime or organic acids to improve process efficiency by 5 to 10%. This is particularly true in light of the market value of so-called SO 2 “removal credits” and the potential for significant economic gain. However, the use of additives at the absorber may cause difficulties with the implementation and performance of downstream biological treatment systems.
[0006] For example, Flue Gas Desulfurization (FGD) process wastewater contains elevated levels of chlorides; significant concentrations of heavy metal contaminants such as chromium, mercury, and selenium; often high levels of nitrates; and a very high solids content that consists primarily of calcium sulfate, calcium carbonate, magnesium hydroxide, and fly ash.
[0007] Treatment of FGD wastewater is a significant need for utility operations. Physical/chemical treatment processes are typically used for neutralization and calcium sulfate desaturation, removal of some heavy metals, clarification and sludge thickening. However, conventional chemical precipitation techniques do not reliably eliminate heavy metal contaminants such as selenium and hexavalent chromium below outfall discharge limits established by newer, more stringent regulatory requirements. Nor do these current practices remove nitrogenous pollution.
[0008] FGD process wastewater is the focus of increasingly stringent effluent requirements, with outfall discharge standards (monthly average and daily maximum) typically established for:
pH Total Suspended Solids (TSS) Total Nitrogen (TN) Heavy Metals including but not limited to Arsenic, Chromium, Copper, Mercury & Selenium Sulfides.
[0014] Selenium is an essential micronutrient for animals and bacteria. However, it becomes highly toxic when present above minute concentrations. The oxidized species of selenium, selenate (Se VI) and selenite (Se IV), are highly soluble and bioavailable, whereas reduced forms are insoluble and much less bioavailable. Regulatory limits for soluble selenium remain variable with targets ranging from 800 ug/L down to the U.S. national drinking water standard of 50 ug/L, frequently depending upon the discharge receiving water body.
[0015] Selenium exists in multiple valence states in the natural environment and the impact of selenium speciation on treatment efficiency is known. Notably, Selenium in the form of Selenite (Se IV; SeO 3 ) can be removed with 65 to 85% efficiency using physical-chemical treatment approaches while Selenate (Se VI; SeO 4 ) removal efficiency is limited to <10% with physical-chemical treatment.
[0016] It would therefore be helpful to provide an enhanced biological treatment approach to circumvent such problems, optimizing downstream removal of TN and heavy metals from FGD wastewater while maintaining SO 2 removal efficiency at the absorber stage.
SUMMARY
[0017] A method of treating flue gas and wastewater generated by treating the flue gas is disclosed and includes:
introducing the flue gas and an organic acid conditioning agent into a wet-oxidation scrubber/absorber substantially to remove sulfur dioxide from the flue gas and condition resulting FGD wastewater for downstream biological treatment; introducing FGD scrubber wastewater generated by the absorber into an anoxic biological reactor to substantially denitrify and/or reduce selected heavy metals in the FGD scrubber wastewater; and introducing substantially denitrified wastewater into an anaerobic biological reactor to substantially reduce the amount of sulfate and/or selected heavy metals in the FGD scrubber wastewater.
[0021] A system for treating flue gas and wastewater generated by treating the flue gas is disclosed and includes:
a wet-oxidation scrubber/absorber comprising a flue gas inlet, a flue gas treatment fluid inlet, an organic acid conditioning agent inlet, and a wastewater outlet; an anoxic reactor located downstream of the wet-oxidation scrubber/absorber to substantially denitrify FGD scrubber wastewater generated by the absorber; and an anaerobic reactor located downstream of the anoxic reactor to substantially reduce the amount of sulfate and/or selected heavy metals in the FGD scrubber wastewater.
[0025] A method of treating FGD scrubber wastewater includes:
introducing FGD scrubber wastewater generated by combining flue gas and an organic acid conditioning agent in a wet-oxidation scrubber/absorber into an anoxic reactor to substantially denitrify the FGD scrubber wastewater; and introducing substantially denitrified wastewater into an anaerobic reactor to reduce the amount of sulfate and/or selected heavy metals in the FGD scrubber wastewater.
[0028] A system for treating FGD scrubber wastewater includes:
an anoxic biological reactor located downstream of a wet-oxidation scrubber/absorber to substantially denitrify FGD scrubber wastewater generated by the absorber; and an anaerobic biological reactor located downstream of the anoxic reactor to substantially reduce the amount of sulfate and/or selected heavy metals in the FGD scrubber wastewater.
BRIEF DESCRIPTION OF THE DRAWINGS
[0031] FIG. 1 is a schematic diagram of a representative process flow for a wet-oxidation scrubber/absorber system and associated conventional FGD wastewater treatment system.
[0032] FIG. 2 is a schematic flow diagram of a representative biological treatment system for FGD scrubber wastewater.
DETAILED DESCRIPTION
[0033] It will be appreciated that the following description is intended to refer to specific aspects of this disclosure selected for illustration in the drawings and is not intended to define or limit the disclosure, other than in the appended claims.
[0034] This disclosure relates to biological treatment systems for FGD scrubber wastewater, encompassing the feed of a pure organic acid conditioning reagent, such as formic acid, to the wet-oxidation scrubber/absorber and later followed by a combination of anoxic, anaerobic and aerobic staged activated sludge reactors and associated clarification systems for removal of TN, reduction and precipitation of heavy metals and elimination of suspended solids from the FGD purge stream.
[0035] This disclosure also relates to processes for biological treatment of FGD scrubber wastewater, particularly to treatments that improve the removal efficiency of TN and heavy metals including but not limited to selenium.
[0036] Turning now to the drawings in general and FIG. 1 in particular, it will be appreciated that a selected, representative pollution control system 10 described below removes FGD wastewater contaminants. The treatment system 10 includes a line 12 to add a pure organic acid conditioning reagent, such as formic acid, to absorber 14 as indicated in FIG. 1 .
[0037] The absorber 14 also connects to a particle scrubber 16 and a recirculation tank 18 . The recirculation tank 18 directly receives flue gas treatment fluid through supply line 20 which is indirectly supplied into absorber 14 by way of line 22 . Flue gas treatment fluid may comprise, among other things, a lime/limestone water slurry. Treated flue gases exit absorber 14 through line 24 , are reheated by reheater 26 and then moved to stack 28 by fan 30 .
[0038] On the other end, FGD scrubber wastewater exits absorber 14 through line 32 and enters recirculation tank 18 . Selected portions of FGD scrubber wastewater exit through recirculation tank 18 and may proceed to clarifier 34 . This may be followed by passage of the clarified wastewater to holding tank 36 . Wastewater contained in holding tank 36 can be recycled to recirculation tank 18 by way of line 38 . The partially dewatered sludge may be channeled from clarifier 34 to vacuum filter 40 by way of line 42 , where most of the remaining water is removed. The waste sludge can then be sent to a settling pond or landfill 44 .
[0039] In accordance with selected aspects of this disclosure, FGD scrubber wastewater may also flow from clarifier 34 to additional treatment systems such as a biological treatment system of FIG. 2 by way of line 46 and as activated by valve 47 .
[0040] Turning now to FIG. 2 , a selected, representative biological treatment system 48 for FGD scrubber wastewater is shown in a schematic form. The system 48 includes an inlet 50 , a staged suspended growth biological reactor 52 comprising anoxic 54 and anaerobic 56 zones, an intermediate clarifier 58 , an aerobic suspended growth biological reactor 60 , a final clarifier 62 , a storage tank 64 and a filtration stage 76 .
[0041] The biological treatment system 48 of FIG. 2 can perform the following functions:
Anoxic Stage—Denitrification (Nitrate reduction) and/or reduce selected heavy metals Anaerobic Stage—Selected heavy metal reduction and precipitation, particularly Selenium reduction Aerobic Stage—Nitrification (ammonia reduction) and organics reduction.
[0045] The biological treatment system 48 may receive influent feed from an upstream physical-chemical treatment system such as from clarifier 34 , for example, of FIG. 1 , in the form of deoxygenated FGD purge wastewater. The biological reactors of the system 48 may include completely mixed, continuous flow, activated sludge reactors.
[0046] The first cell (or reactor 54 ) in the system 48 is the anoxic stage, where nitrates are reduced to nitrogen gas via denitrification reactions. As FGD wastewater is deficient in macronutrients, including ammonia nitrogen and orthophosphorous, as well as many of the micronutrients required to support biological growth, there is a process requirement for supplemental nutrient addition to yield efficient treatment performance. Reactor 54 is thus fed with a biodegradable nutrient blend, containing macro- and micronutrients to maintain microbial growth.
[0047] Nutrients include but are not limited to supplemental carbon such as waste sugar, corn syrup, molasses or the like, urea or the like to provide ammonia nitrogen, phosphoric acid, micronutrients and yeast extract to provide necessary trace metals and growth factors. Fermentation of sugars dosed into the anoxic reactor 54 results in the conversion of sucrose to volatile fatty acids (VFAs) that sulfate/selenium reducing microorganisms are capable of metabolizing efficiently in the downstream anaerobic reactor stage(s). Additional carbon sources such as lactate, acetate or the like may also be added directly to the anoxic/anaerobic reactors to enhance selenium removal by enriching the selenium reducing microorganisms.
[0048] Further, addition of a pure organic acid stream, such as formic acid, through line 12 of absorber 14 provides a means to introduce a biodegradeable carbon substrate to the wastewater that can provide COD to the system for downstream biological removal of nitrates and selected heavy metals. For example, using the COD factor for formic acid of 0.35, a dosage of 200 mg/L formate equates to a theoretical COD dosage of about 70 mg/L.
[0049] The anoxic/anaerobic biological reactor 52 may be an overflow, under-flow weir design which mimics a plug-flow system without the need to incorporate separate reactor tanks that are physically isolated from one another. Other configurations/structures may be used as appropriate. Operational inputs for successful treatment involve targeting the appropriate oxidation-reduction potential (ORP) in the various reactor stages. Thus, the anoxic reactor 54 may preferably be maintained in the range of about −50 to about −300 mV to yield efficient denitrification.
[0050] The role of the anoxic denitrification reactor 54 is important. We found that efficient removal of selected heavy metals such as selenium substantially depends upon sequential substrate removal, specifically the prior elimination of nitrates.
[0051] Additionally, the efficiency of selenium removal is dependent upon the species present in the wastewater matrix. It is known that selenite (Se IV) is somewhat efficiently removed via physical chemical means while selenate (Se VI) requires biological treatment to obtain significant reductions. Surprisingly, we found that efficient biological removal also depends on the nature of complexes, such as organo-selenium compounds, formed within the wastewater matrix and addition of reagent additives to the scrubber/absorber heavily impacted the contaminants formed. We found that many organic complexes of selenium formed as a result of the use of organic acid containing manufacturing waste by-product mixtures at the absorber. These organo-selenium complexes were found to be surprisingly recalcitrant to selenium reduction by the microbial population in downstream biological reactors. We discovered that use of a pure organic acid reagent, such as formic acid, to improve SO 2 removal efficiency at the scrubber further provides downstream advantages by yielding a wastewater matrix that could readily be treated for selenium removal. The staged biological reactors create a reducing environment for the conversion of selenate or selenite to elemental selenium, which precipitates out of solution into the wastewater solids.
[0052] The partially treated FGD wastewater leaves the anoxic reactor 54 substantially devoid of nitrate contamination and flows into the next cell (i.e., the anaerobic reactor 56 ), which in one aspect may be operated at an ORP in the range of about −200 to about −500 mV, where sulfate and heavy metal-reducing organisms begin to remove sulfates and the selected heavy metals from the wastewater. The treated water then flows to an optional third cell (anaerobic reactor stage) to ensure that heavy metals are removed to levels allowing outfall discharge permits to be met.
[0053] The treated effluent from the anoxic/anaerobic biological reactors 54 / 56 may flow into a mix chamber allowing for chemical addition to improve downstream sedimentation within the intermediate clarifier 58 . From the mix chamber of the anoxic/anaerobic reactors 54 / 56 , the treated effluent flows into a settling type intermediate clarifier 58 , where TSS is settled out and the clarifier underflow solids are recycled to the anoxic reactor 54 by lines 66 and 68 as return activated sludge (RAS) or sent to a sludge holding tank (not shown) by line 70 as waste activated sludge (WAS).
[0054] From the intermediate clarifier 58 , the partially treated FGD wastewater flows into the aerobic biological reactor 60 for removal of BOD and ammonia. In one aspect, the aerobic biological reactor 60 includes operation at positive ORP.
[0055] From the aerobic reactor 60 , the FGD wastewater flows into a settling type final clarifier 62 , where TSS is settled out and clarifier underflow solids may be recycled to the head of the aerobic reactor 62 by lines 72 and 74 as return activated sludge (RAS) or sent to a sludge holding tank (not shown) by line 70 as waste activated sludge (WAS).
[0056] Finally, the clarified water flows into a wet effluent well/tank 64 for pumping to pressure filters 76 and ultimately discharge to the environment. The filters may be gravity sand, multimedia or the like type filters.
[0057] Powdered Activated Carbon (PAC) or other adsorbent materials such as charred poultry waste or the like added to the anaerobic and/or aerobic biological reactor will also adsorb any remaining organo-selenium complexes to assist reaching a final effluent selenium concentration that is below about 200 μg/L. PAC can be added at a dosage of about 550 ppm, for example.
EXAMPLE
[0058] A biological treatment system comprising of a 2-stage, completely mixed, anaerobic activated sludge reactor having a total reactor volume of approximately 2,000 gallons followed by a 500-gallon clarifier and an aerobic activated sludge reactor and final clarifier was fabricated and installed on a sidestream of FGD scrubber blowdown at an operating power generating station.
[0059] The facility initiated pure organic acid addition in the form of formic acid to the absorber to enhance the downstream biological treatment process while continuing to provide SO 2 removal at the wet-oxidation scrubber/absorber. Analysis revealed that the soluble oxyanions of Selenium, SeIV and Se VI, represented a significantly greater fraction of the total Selenium present in the sample matrix upon initiation of the pure organic acid feed to the wet-oxidation scrubber/absorber when compared to results obtained with the feed of an organic acid containing manufacturing by-product mixture. The use of a pure organic acid feed resulted in significant reductions in the levels of complexed selenium present. Subsequently, this resulted in improved treatability of the FGD wastewater with the performance of the biological treatment system greatly enhanced as noted below.
[0060] The staged activated sludge design was found to yield substantially complete denitrification of influent FGD scrubber wastewater under anoxic conditions, consistently achieving effluent NO 3 -N concentrations below 1 mg/L for influent nitrate levels ranging from 200 to 600 mg/L.
[0061] Concurrent removal of sulfate and selenium was demonstrated under anaerobic conditions, with effluent soluble selenium concentrations consistently below 200 μg/L. Furthermore, the reduced environmental conditions required for both sulfate and oxidized selenium reduction was also found to provide the reducing conditions necessary for reduction and precipitation of additional heavy metal species including mercury and hexavalent chromium.
[0062] Surprisingly, the performance of the aerobic reactor, intended to perform polishing treatment for removal of excess CBOD and ammonia nitrogen was found to exhibit significant additional removal of soluble selenium species.
[0063] Furthermore, the aerobic reactor performance was found to be much less sensitive to changes in the influent soluble selenium concentration allowing for quick adaptation to system upsets that result in rapid increase in influent Se levels.
[0064] The benefits brought about by the methods and systems described above may include:
The complexity of Selenium speciation within FGD scrubber wastewaters may be reduced or eliminated by feeding a pure organic acid conditioning additive, such as formic acid, to the wet-oxidation scrubber/absorber. Subsequently, this approach improves downstream biological treatment while maintaining SO 2 removal efficiency at the absorber. Use of a staged biological reactor approach to support the growth of distinct groups of bacteria within the naturally occurring population. Use of conventional suspended growth activated sludge technology eliminates need to backwash or flush reactors periodically to remove captured waste material. Reactors are seeded with biomass from natural microbial populations avoiding the need to regularly add “specialized” microbial cultures and thereby reducing annual operational costs. Treatment approach provides operational flexibility and stable operations/performance under highly variable influent conditions. Biological removal of selenocyanate forms and other complexed selenium species that are much harder to remove with conventional iron-coprecipitation treatment strategies. Biological removal of heavy metals, including selenium, in absence of reducing agent feed, such as potassium permanganate, to the biological reactors.
[0072] Thus, the use of suspended growth biological treatment methods and systems for the removal of TN and heavy metal contaminants from FGD wastewater offers several potential advantages when compared to conventional chemical precipitation techniques including the use of biodegradable nutrients as opposed to iron-based reagents, elimination of nitrogen-containing pollution, elimination of difficult to remove heavy metal contaminants such as selenate to extremely low levels, production of less sludge and reduced operational expenses.
[0073] Although the above methods and systems have been described generally in accordance with the figures, it should be understood that the above descriptions and figures are merely representative, selected examples. Variations and/or substitutions may be made as appropriate by those skilled in the art. For example, although we have shown selected biological reactors in various shapes and configurations and made from selected materials, it should be understood that such shapes, configurations and materials can be changed as appropriate in accordance with the surrounding environment makes practicable. Also, biological reactors may contain support media to provide a means of attached biological growth in addition to the suspended growth fraction. Of course, other components and steps known in the art may be added to meet various conditions at particular sites. | Systems and methods of treating flue gas and wastewater generated by treating the flue gas are disclosed and include introducing the flue gas, a flue gas treatment fluid that removes sulfur dioxide from the flue gas; and an organic acid conditioning agent into a wet-oxidation scrubber/absorber; introducing FGD scrubber wastewater generated by the wet-oxidation scrubber/absorber into an anoxic biological reactor to substantially denitrify the FGD scrubber wastewater; and introducing resulting substantially denitrified FGD scrubber wastewater into an anaerobic biological reactor to substantially reduce the amount of sulfate and/or selected heavy metals in the FGD scrubber wastewater. | 2 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] Not applicable.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not applicable.
BACKGROUND OF THE INVENTION
[0003] The present invention relates to a portable garden box for use in growing vegetables or other plants. More specifically, the present invention relates to a portable garden box that allows for the growing of plants in selected spaces while providing a protective barrier against foraging animals.
[0004] Portable garden boxes or portable garden beds have been known in the prior art and have become even more popular today. Gardening is a pastime that many people and it knows no age barriers and is accessible to those with physical limitations of many kinds. The technology behind gardening is something that can spark a rabid discussion among aficionados and can readily inform the casual observer that this is a mainstream activity that even though it is well practiced, it remains fraught with specific problems and issues that arise even with the most modest of undertakings.
[0005] One problem that has arisen and which has been observed by the applicant is the need for a portable garden that provides protection for the plants that are grown. Even in urban environments, there are pests that can invade a garden bed and devastate the plants. These include small animals such as cats or mice, and can include larger insects such as moths. In addition, there are other so-called pests, notably humans, who can also present problems with the garden box. Small children, for instance, invariably find the garden box an attraction that needs to be explored, and unfortunately, this often leads to tragedy when the plants are damaged or destroyed. The problem can also arise from adults who either don't recognize the existence of the garden box or believe it to serve as an ashtray or waste receptacle and may be prone to bump it or worse.
[0006] There have been garden box inventions in the prior art that have taken many different approaches to portable gardening. For instance, U.S. Pat. No. 3,118,249 (Bard, et al) teaches the use of a stackable tray for growing mushrooms. Multiple stacking trays can be used for mushroom farming since direct sunlight is not necessary for the propagation of mushrooms, unlike vegetables or flowers. The short wall in this concept would provide only nominal protection against the hazards that are known to occur with respect to gardening in portable beds or boxes.
[0007] In U.S. Pat. No. 6,681,522 B2 (Marchioro) a modular gardening system is disclosed that utilizes standardized wall and post construction to allow substantial gardening units to be installed in buildings, or lobbies, or arenas, and the like. The invention also includes trellises for climbing plants. This invention is not as truly as portable as that envisioned by the applicant herein and it does not provide the functionality for setting up discrete garden boxes with protective fences.
[0008] The use of fencing for assisting in the cultivation of climbing plants is shown in U.S. Pat. No. 5,752,341 (Goldfarb) which displays a free-standing trellis that can be used in conjunction with portable garden boxes. This invention does not teach the protective fencing of the present invention, however, nor does it provide an integrated device for the growing of plants in select growing environments.
[0009] Other inventions that are known also provide containment for plants of various types such as, U.S. Pat. No. 6,134,834 (Ripley, Sr., et al) plant container with modules for growing differing types of plants; U.S. Design Patent D402,229 (Christensen) a design for a knock-down planter box; U.S. Pat. No. 1,129,554 (Courtney) planter box with subirrigation; and U.S. Pat. No. 2,814,427 (Emery) a molded pulp plant container. None of these reveal a portable garden box that has integrated protection for pests and others, or that can be used as easily as the present invention in selected growing environments. These and other attributes and features of the present invention will be disclosed in more detail below.
SUMMARY OF THE INVENTION
[0010] A novel portable garden box comprises a tub with formed fence postholes which are engageable by fence posts that are affixed to fencing that is vertically oriented above the tub lip and about the periphery of the tub. The fencing, fence posts and tub form an integrated gardening unit that is competent to receive soil within the tub and which is suitable for growing plants. The tub may also contain drain holes allowing for the drainage of percolated water from the soil.
[0011] The portable garden box of the present invention may be supplied to end users in the form of a kit with the fencing and the posts affixed appropriately and with the combination sized for immediate assembly.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a front isometric view of the garden box of the present invention with the fencing installed on the fence posts and the fence posts installed into their corresponding fence postholes in the tub.
[0013] FIG. 2 is another front isometric view of the garden box of FIG. 1 , with the fencing shown in an orientation above its installation alignment on the tub, in a condition that is transitioning towards installation or towards removal of the fencing from the tub.
[0014] FIG. 3 is a side cross-sectional view of the garden box of FIG. 1 taken at Section 3 - 3 .
[0015] FIG. 4 is a side cross-sectional view of the garden box of FIG. 1 taken at Section 4 - 4 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0016] A new garden box in accordance with the present invention is shown in FIGS. 1 and 2 , with the garden box 10 comprising the tub 12 and the fence 14 . The fence 14 further includes the fence post(s) 16 with the fence post top(s) 18 and the fence post bottom(s) 20 . The tub 12 includes the tub lip 22 , the tub wall(s) 24 , the post hole(s) 30 , the tub bottom 32 , the drain holes 34 and the tub corner(s) 36 . The soil 26 is shown in FIG. 1 as partially filling the tub 12 .
[0017] Turning to FIG. 3 , the gap 40 , which is the space between the bottom of the fence 14 and the tub lip 22 is shown as is the freeboard 42 which is the space above the top level of the soil 26 and the tub lip 22 .
[0018] The representation of the present invention in FIG. 4 shows the same features as above as a cross section taken in the area of one of the tub corners 36 .
[0019] The use of the portable garden box 10 of the present invention is perhaps best explained in FIG. 2 . In particular, the fence 14 and the fence posts 16 may preferably be pre-assembled when the garden box 10 is supplied in kit form. The fence posts 16 are affixed to the fence 14 by any conventional means, including but not limited to stapling, nailing with brads and the like, or even with glue. The fence 14 itself may be fabricated from a number of different materials, all of which are suited for the purposes intended, including but not limited to so-called chicken wire, wire mesh, fabric mesh or plastic mesh. The qualifying provision is that the fence material has to sufficiently provide barrier protection from the anticipated threat which can come from insects, various animals, as well as children and careless adults. Generally speaking, the preferred material for fence fabrication is a wire mesh similar to chicken wire construction. The fence 14 when made up of materials such as wire has the advantage of retaining a “memory” so that it can be formed to follow the shape of the tub 12 . This aspect of the fence 14 helps to increase the stability of the fence 14 assembly.
[0020] As seen in FIG. 2 , the fence 14 and fence post 16 assembly is generally positioned above the tub 12 for installation. Each of the four fence posts 16 are aligned with a corresponding posthole 30 located on the tub lip 22 and typically located at each tub corner 36 . The assembly is fitted into the postholes 30 and as shown in FIG. 1 , with the fence post bottom 20 extending through the posthole 30 and end up sitting on the same surface as the tub bottom 32 . There is preferred a tight fit between the fence post 16 and the posthole 30 to encourage stability in the fence 14 . The completed garden box 10 that results is freestanding and competent to protect the plants that will be growing in the tub 12 . The fence post(s) 16 are typically fabricated from wood stock although they could be fabricated from plastic stock as well. Wood construction is especially useful when staples or brads are used to affix the fence 12 to the fence post(s) 16 .
[0021] Turning now to the tub 12 construction, the tub 12 is typically fabricated from a plastic resin, and preferentially it is the result of a plastic injection molding process. The tub 12 could be fabricated from fiberglass as well, and it could also be fabricated from steel or other metal. These materials are typically more costly to work with and the plastic construction has the advantage of simultaneous formation of the various tub features such as the tub lip 22 , the postholes 30 and the drain holes 34 when the tub is injection molded.
[0022] The tub 12 sizing and shape is of consideration in the present invention. The preferred embodiment is square since this shape provides for economical packing for shipment since they can be stacked inside each other and can be placed square on skids. A round shape can also be used for shipping and packaging purposes and would, like the substantially square embodiment, be compatible with stacking although it would consume a larger footprint per square foot of useable growing space as compared to the square shape. The square shape also provides maximal square footage for the growing space. The garden boxes 10 of the present invention if arrayed as square units, can be placed in groupings that make the best use of limited floor space on decks or porches. The array of garden boxes 10 also allows for arrangements for rows or other patterns that are symmetrically suited for square shaped construction. In the alternate, round tubs 12 can be used instead without departing from the spirit of the present invention, where the postholes 30 would be distributed equidistant around the diameter of the tub lip 22 in such an embodiment.
[0023] As may be inferred from FIG. 1 , soil 26 is provided to fill the tub 12 to a useable level for growing plants. The type of plants grown are certainly at the discretion of the user, although many times it is anticipated that the present invention will provide excellent service for vegetables. In particular, the use of garden boxes 10 has been stymied by actual observation of the applicant for the reason that they seem very vulnerable to squirrels, rodents and other small animals of this ilk. The usage of the present invention has solved this problem very handily and vegetables can be grown with much success than was previously the case. Thus the growing environment best suited for vegetables is often considered which means a sufficient depth of rich soil, that is drained sufficiently. In the case of the preferred embodiment, the square tub 12 works very well when it is sized approximately four and one-half feet wide and with tub walls 24 that are approximately twelve inches deep. This would provide an ample environment for the plants and remains a size that can still be handled easily by the consumer.
[0024] The fence 14 for the garden box 10 is preferably high enough to thwart the small animals that might seek the plants, and it should also be high enough to gain the attention of adults who might otherwise trip over the garden box 10 . In use, a fence 14 of approximate height of three feet has been shown to be effective. The fence materials, the fence 14 and the fence posts 16 , can be prepared and assembled in advance for the convenience of the user. The fence 12 , as indicated above, is approximately three feet in height, while the fence posts 16 are longer by approximately twelve inches. In any event, the fence 14 and the fence posts 16 can be stowed diagonally within the preferred embodiment of the present invention, allowing them to be packaged as kits that include all necessary components (excepting for the soil 26 ) in one unit. It is also noted that the fence posts 16 do not necessarily have to fit into postholes 30 that are located exclusively at the tub corners 36 . In some cases it may be preferred to have more postholes 30 that just the four contemplated, which could result in postholes 30 distributed about the tub lip 22 at select locations. If additional fence stability is needed, the inclusion of additional postholes 30 would be of benefit.
[0025] It is noted that a gap 40 is typically realized between the bottom of the fence 14 and the top of the tub lip 22 . This gap 40 can be calculated to be roughly equal to the sizes of the holes in the fence 14 itself thus maintaining consistent barrier protection. The gap 40 ensures that the fence 14 will not bottom out on the tub lip 22 which could render the fence 14 unstable. Similarly, there is some freeboard 42 indicated between the top of the soil 26 and the tub lip 22 . This is the natural method for supplying a growing environment and it prevents overflows when watering the plants as well as the inadvertent loss of soils if the level were topped off at the tub lip 22 .
[0026] The use of the present invention is intended to increase the enjoyment of those who have an affinity for gardening, whether this is for the purposes of growing vegetables or flowers, and who may otherwise lack sufficient land. The usage of the garden box 10 allows gardening to take place on porches or decks or other spaces in and around the home. In addition, the garden box 10 may also be used in other settings such as commercial or retail areas as a means for decoration or to provide a pleasing diversion.
[0027] The features and attributes illustrated herein are meant to disclose the invention and are not intended to operate as limitations or to limit the scope of the invention in any way. | A novel portable garden box for use in growing plants, comprises a fence and a tub, where the fence is attached to fence posts that are insertable into the tub. The tub includes a tub lip, four walls, a bottom, postholes for receiving the fence posts and drain holes for providing drainage. The tub is fillable with soil under conditions that provide a suitable growing environment. The garden box, when fully assembled with the fence installed on the tub, provides barrier protection from small animals and the like. The garden box of the present invention is preferably constructed with a substantially square tub that is optimizeable for shipping and packaging purposes and for alignment of the garden boxes in various arrays by the end user. | 0 |
BACKGROUND OF THE INVENTION
The present invention pertains to tunneling machines. More specifically the present invention relates to convertible tunneling machines that employ a low flow of slurry to prevent tunnel face subsidence by creating a liquid balance, but not as a transport medium.
Diverse ground conditions are encountered in the excavation of some tunnels. Sand, marl, limestone, clays, and chalk may all be expected. At times, various types of ground may be encountered simultaneously. The water tables along a tunnel also vary considerably. This inconsistency of tunnel geology demands a convertible machine. In many of these ground conditions, support of the face is necessary to prevent ground settlement or the creation of excessive voids around the tunnel lining. In other areas face support is not necessary. Such a convertible machine that is fast and convenient to reconfigure does not exist in the prior art.
Effective methods of workface control commonly used to support unstable soil faces are the slurry and earth pressure balance (EPB) shield methods. A traditional slurry system requires a large surface plant with filter presses to remove fine clay particles suspended in a dilute slurry. In addition, a large diameter slurry discharge line must be continuously extended as the TBM (tunnel boring machine) advances. This discharge line typically runs the tunnel length to the surface plant.
The other conventional approach for workface control, earth pressure balance, eliminates the slurry discharge line and surface plant. The primary concern with a EPB system is the possibility of plugging inside the very large cutterhead, and for this reason the muck must be kept as fluid as possible. Fluid mixed with appropriate additives must be injected into the head to maintain the proper pressure to ensure face stability. The material most likely to cause plugging is moist clay, but its flowability characteristics can be improved by the addition of polymers. In addition, the torque requirements for cutterhead rotation for a large diameter cutterhead are extremely high for an EPB design. Thus, an adequate system for tunnel face control in unstable soil conditions is currently lacking in the prior art, even aside from the lack of convertability of the conventional slurry and EPB soft ground systems to a hard ground system when desired.
Tunneling machines previously known in the art that either employ a conventional slurry or an earth pressure balance system to control an unstable tunnel workface, or that operate in varying geological conditions, are described below.
United Kingdom Patent No. 1,083,322, issued to Bartlett, uses a tunneling apparatus including a shield containing or supporting a power driven rotary mechanical digging mechanism in front of a bulkhead, in which a liquid thixotropic suspension is delivered under pressure to the space in front of the bulkhead so as to contact the working face on which the digging mechanism acts and the spoil excavated by the digging mechanism is removed together with a proportion of the liquid suspension The material removed from the tunneling shield is partially cleaned or separated, and the cleaned constituent containing a high proportion of the thixotropic suspension is returned to the space in front of the bulkhead. The material removed from the shield is moved to a point at the rear, but within the formed portion of the tunnel, to be cleaned. The discharge duct is preferably at an elevated level in the bulkhead. One result of this construction, as broadly suggested by this patent, is that it may be possible, when conditions permit, to operate the shield as a conventional mechanical tunneling shield without the liquid suspension, and to remove spoil by means of a belt conveyor or the like.
U.S. Pat. No. 4,881,862, issued to Dick, discloses a screw seal having a conveying section feeding into a sealing section within a housing, wherein the sealing section has a divergent cross sectional area. The divergence is predetermined in conjunction with the compressibility and permeability of the bulk solids and the coefficient of friction between the solids and the barrel of the sealing section, so as to permit the formation of a sufficiently dense plug of the solids to form an effective gas seal, but to limit the solids pressures and thereby to control the resulting increase in driving torque. Other features comprise a number of variations in the structures of the conveying and sealing sections, and also the discharge chamber into which the sealing plug is driven. These permit a large variety of applications and with many different types of bulk solid materials.
U.S. Pat. No. 4,848,963, issued to Babendererde et al, discloses an earth pressure shield for a tunnel excavator having a front working compartment formed by a separating wall, having a digging tool and an annular reinforcing space substantially triangular in cross section positioned directly in front of the separating wall. So that extensive restructuring of the machine is not necessary when moving from soft roof to hard ground, the annular reinforcing space is provided with a lower fluid feeder, a controlled upper pressurized air feeder, a plurality of fluid connector pipes which are guided from below to an upper fluid outlet opening into the working compartment, and a fluid level controller.
U.S. Pat. No. 4,844,656, issued to Babendererde et al discloses an earth pressure shield having a front working compartment, having at least one digging or mining tool, and formed by a separating wall, in which an annular space is formed with a top region connected with a regulated pressurized air feed and with a bottom region opened to the digging or mining tool so that the dug or mined earth material is moved with the help of a conveyor unit. At least one fluid pipe is guided from a fluid chamber with a first level controller and with the fluid feeder to a fluid outlet opening to the digging or mining tool.
Behind the working compartment formed with an immersed wall, a bulkhead space is provided by partitioning. The bulkhead is connected in an upper region with the top region of the annular space by an opening in the separating wall and includes the fluid chamber in a lower region. In an additional partitioned chamber or space, a bulkhead space is provided to the rear of the working chamber in which the immersed wall is located and which partitions the front portion of the tunnel and/or digging machine. The drive for the digging wheel, the pressurized air feed for clearing the working compartment, mixing devices, and a screw conveyor all project through this bulkhead space. The lower and larger part of the bulkhead space is filled with water and/or a muck suspension, while the upper part is filled with compressed air which, because of the upper connection of the pressurized air cushion behind the immersed wall, stands under the same predetermined pressure as acts on the earth material behind the immersed wall.
The fluid pipe, which opens in the lower portion of the bulkhead space, guides water and/or the suspension through the upper part of the bulkhead space filled with pressurized air and through the pressurized air cushion located behind the immersed wall in the vicinity of the roof of the front part of the working compartment. Also, feeder means for water and/or suspension, which supply the bulkhead which is penetrated by the digging tool, is connected to the water filled bulkhead space.
The air cushion with a predetermined regulated pressure guarantees the same constant pressure on the earth material located behind the immersed wall and the water and/or suspension located in the partitioned portion. Measuring and control systems provide that the level of the earth material and the water itself are the same, i.e. at the same height. The shear resistance of the earth material in the working compartment prevents the predetermined supporting pressure in the pressurized air cushion from being transmitted to the local front wall, especially in the sensitive roof region. A zone of lower pressure arises in which the water and/or suspension flows into the roof region of the front part of the working compartment through the ducts from the bulkhead rear space.
A nonreturn valve opens only when the predetermined supporting pressure is not attained. Simultaneously the water and/or the suspension standing under the predetermined supporting pressure flows by feed means in the digging wheel into the space through which the digging tool travels in front of the digging wheel.
Mixing and stirring devices behind the immersed wall provide for a uniform mixing of the earth material with the delivered fluid. Regulated pressurized air feed is guided through the partition of the bulkhead space. To obtain the best possible mixing of the dug earth material with the fluid (water an/or suspension), at least one stirring unit is located in the bottom region of the working compartment behind the immersed wall. A nonreturn or check valve for the fluid outlet is provided so that a predetermined supporting pressure is not exceeded.
U.S. Pat. No. 4,818,026, issued to Yamazaki et al, discloses a device that transfers cut bedrock through the cutterhead to the tunneling machine interior. In a central area of the cutterhead compartment is provided a debris receiving chamber into which are channeled the front-end portion of a screw conveyor and the front-end portion of a water supply pipe. A rear-end portion of the water supply pipe is connected to a water-supply source disposed in a rear area of the tunneling apparatus. The water issues from such water supply source to the debris receiving chamber through its upper opening so that the cutterhead compartment is filled with water which buoys up the rock debris to enable the debris to easily enter the debris receiving chamber through its upper opening under the influence of the rotational movement of the cutterhead compartment. The rock debris received in the debris receiving chamber is transported rearwardly together with water by means of the screw element of the screw conveyor, reaching an outlet opening of an outer sleeve of the screw conveyor, and then dropping therefrom to a rock crusher.
U.S. Pat. No. 4,774,470, issued to Takigawa et al, is for a tunneling machine having electromagnetically based sensors that detect and display conditions of the tunnel earth. The invention includes an electromagnetic wave transmitting and receiving unit mounted on the top of the shield machine for radiating electromagnetic impulse waves towards the tunnel earth and for receiving the electromagnetic waves reflected from the tunnel earth. A position sensor collecting information regarding the position of the electromagnetic waves, wave transmitter and receiver unit is included. A data processing unit is provided for processing the signals from the transmitter/receiver and the position sensor as sent through a transmission line. The data processing unit continuously displays the condition of the tunnel earth at the cutting fact.
U.S. Pat. No. 4,630,869, issued to Akesaka et al discloses a shield tunneling machine having a partition wall. A lidded opening is formed in the upper portion of the partition wall. The lid is pivotally connected through an arm to the piston rod of a pneumatic or hydraulic cylinder mounted on the wall member and the cylinder keeps the opening normally closed. However, when the pressure of muck received in the space between the partition wall and the cutterhead exceeds the pressure sent to the cylinder, the lid moves pivotally toward the partition wall against the pressure of the cylinder to open the opening, permitting muck flow into the muck chamber. In the muck chamber are disposed a rotor and a stator constituting a crusher for crushing relatively large gravel entering the muck chamber. The rotor is mounted on a rotary shaft and the stator below the rotor is mounted on the partition wall. High pressure water is sent into the muck chamber through a water supply pipe and the supplied water is discharged from the muck chamber together with the muck to the rear portion of the shield body through a drain pipe.
This shield tunneling machine also comprises a tubular shield body, a partition wall provided in the shield body, a rotary shaft rotatably supported by the partition wall and extending along the axis of the shield body, a cutterhead disposed on the front end of the rotary shaft and including a first cutter provided with a plurality of cutter bits and a second cutter provided with a plurality of roller bits, a mechanism for rotating said cutterhead by means of a rotary shaft and a mechanism for relatively moving straight forward and backward one or the other of the first and second cutters. The cutter bits and roller bits are mounted respectively on the first and second cutters so that one of the cutter bits and roller bits can be projected and the other can be retracted for excavation according to the geology of the face. Thus, this shield tunneling machine can be used for excavating either soft or hard ground. Further, the roller bits do not hinder the excavating operation of the bits in excavating the soft layer and the cutter bits are not damaged by the excavating operation of the roller bits in excavating the hard layer.
U.S. Pat. No. 4,629,255, issued to Babendererde discloses a tunneling apparatus with a lateral shield having a front end normally engaged longitudinally against a tunnel end face, a digging tool at the front end of the shield and engageable with the tunnel face, and a drive for displacing the tool and digging the tunnel face. A transverse pressure wall across the shield forms a pressurizable chamber inside the front end of the shield around the tool at the tunnel face. A conveyor tube longitudinally traverses and has a front end open ahead of the wall in the chamber and is adapted to receive material freed from the tunnel face by the digging tool. An auger can be rotated in the tube to displace freed material back in it from its front end to its rear end. A chute opens upwardly into the rear end of a conveyor tube to receive material therefrom and a pump tube extends longitudinally back from the chute. A piston pump between the chute and the pump tube can displace material from the chute back to the tube. This disclosure recognizes that when driving a tunnel or shaft in soft ground the material that is dug out can be transported relatively easily by a piston pump constructed along the lines of a heavy-duty concrete pump. The tube can be a flexible hose that will not hinder operations behind the machine.
This patent also discloses a piston pump system attached to the conveyor tube that is pressurized by the earth slurry transported therein. The piston pump that drives this slurry through a flexible tube is said to be less cumbersome than the belt type conveyors used in the prior art.
U.S. Pat. No. 4,607,889, issued to Hagimoto et al, pertains to an apparatus for the mixing of a muddying material, such as a bentonite/slurry mix, in the cutterhead assembly. Specifically, rotary mixing means are situated in the outer periphery of the cutterhead chamber and the central portion of the cutterhead chamber. These mixing means rotate at different speeds and opposite directions. Specifically, the mixing means in the central portion rotates faster than that in the outer periphery in order to improve mixing efficiency in the entire chamber. The specific improvement over the prior art is said to be that the central portion of the rear wall of the cutterhead chamber rotates with the cutterhead as opposed to being stable as in the prior art. Consequently, fewer gaskets or seals are needed. In order to regulate the pressure of the muddying material in the cutterhead chamber, a conveyor cylinder having a screw conveyor and filled with muddying material is controlled to remove material from the cutterhead chamber at a variable rate. Slurry or mudding material is transferred from the cutterhead chamber through the tunneling machine through a conventional conveyor cylinder with screw auger. The slurry contained within the conveyor cylinder maintains the desired back pressure.
U.S. Pat. No. 4,456,305, issued to Yoshikawa, provides a shield tunneling machine which comprises a hollow shield main body; a cutter head rotatably disposed at one end of the main body; a pressure chamber formed within the main body immediately behind the cutterhead; an atmospheric pressure compartment formed within the main body in the rear of the pressure chamber; and an earth removing apparatus provided within the main body and holding the pressure chamber in communication with the atmospheric pressure compartment. The earth removing apparatus comprises a tubular casing having, at a front end portion thereof, an earth inlet opening to the pressure chamber, and at the rear end portion thereof a closable earth outlet communicating with the atmospheric pressure compartment, and an earth transport conveyor rotatably provided within the casing and comprising a helically twisted strip. Since the earth transport conveyor has no rotary shaft, the apparatus is capable of transporting and discharging earth containing relatively large solid fragments even when the shield main body or the tubular casing has a reduced diameter.
In this patent disclosure the earth from the workface, which may or may not be slurry, is transferred from the pressure chamber to the atmospheric pressure compartment by a conventional tubular casing having a novel helically twisted strip. The plug of earth in the conventional tubular casing maintains the desired pressure within the tubular casing.
U.S. Pat. No. 4,406,498, issued to Akesaka, teaches a shield tunneling machine in which the shield body comprises a thrust ram or advancing jack and a diaphragm is provided internally across the shield body in a portion spaced apart rearwardly of the front end of the shield body. The diaphragm has an upper opening which is a muck inlet. A bit or scraper is provided in the peripheral portion of the opening. The diaphragm and a member interposed therebetween constitute a casing which defines a muck chamber behind the diaphragm, the muck chamber being usually charged with a liquid. The opening in the diaphragm is an inlet through which the muck is introduced into the muck chamber. The muck inlet is closed and opened by a cover member.
The cover member is coupled to the piston rod of a dual hydraulic piston cylinder device attached to a wall member. A hydraulic pressure circuit for introducing a liquid pressure of a predetermined level into the cylinder retains the piston in a given position within the cylinder so that the cover member normally closes the muck inlet. As long as the pressure of the muck charged between the face and the diaphragm is maintained at a level capable of preventing collapse of the face, more specifically within the range of pressure larger than an active earth pressure in the face ground but smaller than the passive earth pressure thereof, the cover member closes the muck inlet. When the pressure of the muck rises above a predetermined level, the cover member is urged by the muck to open the muck inlet, thereby allowing admission of muck through the inlet. As soon as the muck pressure drops to the predetermined level due to admission of the muck into the muck chamber, then the hydraulic piston cylinder again urges the cover member to its muck inlet closing position.
The muck is discharged from the muck chamber through a muck discharge pipe provided in the casing member in the lower portion of the muck chamber. Discharge of the muck out of the muck chamber is accomplished without changing the muck pressure to a substantial extent and hence without causing collapse of the face.
U.S. Pat. No. 4,165,129, issued to Sugimoto et al, teaches a tunneling machine having a cutter chamber disposed at the front end of a shield frame and driven by cutter drive motors. Sealing members are sealingly disposed between the periphery of the cutter and the front edge of the shield frame. The front end portion of a screw conveyor is placed in the cutter chamber and is sealed in such a way that even when the cutter is driven, the water-tightness of the cutter chamber is maintained. A mucking adjustor for controlling the concentration of the slurry is disposed immediately below an unloading opening at the rear end of the screw conveyor and is communicated through a water supply pipe with a water tank, and through a discharge pipe with a muck-water separator. The muck separated by the separator is transported into a hopper which in turn transports the separated muck to a suitable disposal site. The water separated by the muck-water separator is returned to the water tank for recirculation.
The muck from the face fills not only the cutter chamber but also the screw conveyor through a loading opening so that an uncontrolled flow of the muck from the face to the cutter chamber is prevented. The muck in the cutter chamber is transported by the screw conveyor in a controlled quantity and is discharged through an unloading opening into the mucking adjuster. The muck in the mucking adjuster is agitated with the water charged through the water supply pipe and is discharged through the discharge pipe to the ground surface. The uncontrolled flow of water from the face into the cutter chamber can be prevented by maintaining the pressure of water charged into the mucking adjuster the same as the ground water pressure at the face. Even if the pressure of water charged into the mucking adjuster is changed, the fluctuating pressure is not transmitted to the face by the muck filled in the screw conveyor so that the face is maintained at a stable condition.
As apparent from the state of the prior art, a need exists for a tunneling machine operable in a "closed mode" for soft ground in which the cutterhead is pressurized, and in which low slurry flow is employed to prevent subsistence of an unstable tunnel face by creating a liquid balance without need for high volume recirculation of the slurry and without need for a bulky muck/slurry separation plant, a conventional slurry tunneling systems.
A need also exists for a tunneling machine of the above type in which a fast and convenient conversion can be performed between "closed mode" and "open mode" operation where the cutterhead is not pressurized and competent ground is tunneled.
A need exists as well for a tunneling machine of the above type in which the pressure lock employed in the "closed mode" of operation is a carousel type pressure lock having a substantially constant rate of material processing and a low profile.
A need further exists for a tunneling machine of the above type having an optional secondary separation system in the "closed mode" with hydrocyclone type removal of fines and a simple fresh bentonite addition capability for increased tunnel face stabilization.
SUMMARY OF THE INVENTION
The present invention is a tunneling machine designed to be operable in both a "open mode" for use in stable geological formations and in a "closed mode" for use in unstable or high water content inflow geological formations. The "open mode" provides high tunneling machine advance rates, while the "closed mode" provides a pressurized low flow slurry system that prevents subsidence of the tunnel face. In the "closed mode", the low flow slurry system employ pressurized slurry to stabilize the face but not as a transportation means for the muck. The liquid balance necessary for face stabilization in the "closed mode" is accomplished by adding sufficient water to control the face, to fluidize the muck and to reduce cutterhead torque. The low flow slurry system of the "closed mode" offers positive control of the slurry pressure and-does not require the high capacity pumps and large diameter pipe lines of a standard slurry system employed to transport muck.
The tunneling machine of the present invention includes a cutterhead powered by drive motors and axially rotatable relative to the tunneling workface. The cutterhead preferably includes a plurality of rolling cutters units mounted thereto. Adjacent the rolling cutter units are slit-like openings for passage of muck into the cutterhead chamber. Drag picks adjacent the slit-like muck openings are employed to promote passage of softer muck into the cutterhead.
Thrust cylinders provide forward thrusting of the cutterhead relative to the tunneling machine, and articulation cylinders provide angular movement for steering of the cutterhead face.
A belt conveyor, for use in the "open mode", and a screw conveyor, for use in the "closed mode", are oriented side-by-side in the cutterhead chamber. Retraction of the belt conveyor and assembly of a pressurized bulkhead converts the tunneling machine into the "closed mode" for unstable tunnel face conditions.
In the "open mode" high cutterhead speed is used to excavate the face with cuttings entering the cutterhead through the muck openings. Cuttings are then channeled along the belt conveyor and loaded onto a secondary conveyor which leads to muck cars for removal from the tunnel in a conventional manner.
In the "closed mode" of operation a relatively low cutterhead speed is employed. A slurry, optionally containing bentonite or the like, is pumped into the cutterhead chamber at a pressure to balance the prevailing ground water or earth pressure. The combination of pressure and the consolidating action of bentonite (if present) essentially prevent face collapse as excavation proceeds. The pressure at the tunnel face is a function of the back pressure in the muck discharge side of the system and the slurry flow pressure of the supply -side of the system. The back pressure in the discharges the system is controlled by the pressurized cutterhead, pressurized screw conveyor, and a pressure lock. The screw conveyor communicates with the cutterhead and the pressure lock. The pressure lock in turn communicates with a dewatering system kept at essentially atmospheric pressure which passes solid material from the tunnel face to a secondary conveyor for removal from the tunnel. In one embodiment of the present invention, the supply side of the system includes liquid from the dewatering tank, which is sent to a reservoir/accumulator. The reservoir/accumulator controls the slurry supply flow by feeding a low flow slurry into the cutterhead chamber to maintain tunnel face pressure.
In an alternate "closed mode" embodiment of the present invention, a secondary refining and separation system, having a fresh bentonite mixing system is connected to the reservoir/accumulator for use of bentonite-added slurry to maintain the tunnel face in the supply side of the system. The secondary separation system of this alternate embodiment also includes a hydrocyclone separation system that receives the fine particles from the screw conveyor which do not separate by gravity. These fine particles are processed by the hydrocyclone units such that the main fluid discharge from the hydrocyclones, containing the very fine solids fraction, is delivered to the fresh bentonite mixing system. Other materials from the hydrocyclone separation system, along with solids from the dewatering system, are transported along a secondary conveyor for removal from the tunnel.
In a preferred embodiment of the present invention, the pressure lock connecting the pressurized screw conveyor and the dewatering tank employed in the "closed mode" is a dual chambered pressure lock having swingable inlet gates and outlet gates that alternately allow each of the two chambers to be filled under pressure with material from the screw conveyor and to then be emptied into the dewatering tank system at substantially atmospheric pressure. In this manner, while one of the two dual chambers is being filled with material from the screw conveyor under pressure, the other of the two chambers is emptying its material into the dewatering tank at atmospheric pressure.
In an alternate embodiment of the present invention, the pressure lock is a carousel type lock mechanism allowing substantially constant material conveyance with a low profile configuration. This carousel pressure lock includes a plurality of wedge-shaped chambers that sequentially communicate with the screw conveyor under pressure and then sequentially rotate within the carousel under pressure to a carousel exit that is at atmospheric pressure and is in communication with the dewatering tank.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other features of the invention will be more fully appreciated when considered in the light of the following specification and drawings describing and illustrating typical embodiments thereof, in which:
FIG. 1 is a side elevational view of a tunneling machine typifying the present invention;
FIG. 2 is a front view of the cutterhead of the tunneling machine of FIG. 1;
FIG. 3a is an enlarged partially exposed view of the cutterhead of FIG. 2 showing the screw conveyor and screw conveyor hopper employed in the "closed mode";
FIG. 3b is an enlarged partially exposed view of the cutterhead of FIG. 2 showing the screw conveyor, belt conveyor and belt conveyor hopper employed in the "open mode";
FIG. 3c is an enlarged partially exposed view of the cutterhead of FIG. 2 showing the convertible hopper usable in both the "open mode" and the "closed mode".
FIG. 4 is a cross-sectional view of the tunneling machine of FIG. 1 taken along lines 4--4 thereof;
FIG. 5 is a cross-sectional view of the tunneling machine of FIG. 4 taken along lines 5--5 thereof;
FIG. 6 is a schematic diagram illustrating the "closed mode" of operation of the tunneling machine of FIG. 1;
FIG. 7 is a schematic diagram of an alternate embodiment of the "closed mode" of operation of the tunneling machine of FIG. 1;
FIG. 8 is a side elevational view of the dual-chamber pressure lock employed in the "closed mode" of operation of the tunneling machine of FIG. 1;
FIG. 9 is an end view of the dual-chamber pressure lock of FIG. 8;
FIG. 10 is a side elevational view of the dual-chamber pressure lock of FIG. 8 with the inlet gate and outlet gate thereof oriented in opposite chambers;
FIG. 11 is a side elevational view of the dual-chamber pressure lock of FIG. 8 with the inlet gate and outlet gate thereof oriented in the same chamber;
FIG. 12 is a side elevational view of an alternate embodiment of the pressure lock of the present invention having a low profile carousel configuration; and
FIG. 13 is a top view of the carousel-type pressure lock of FIG. 12; and
FIG. 14 is a partial view of the side elevational view of the carousel type pressure lock of FIGS. 12 and 13.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The first embodiment illustrated pertains to a tunneling machine having a low flow liquid balance system. Referring to FIGS. 1 through 5, the overall components of the tunneling machine are described. Referring first to FIGS. 1 and 2, tunneling machine 10 includes a frame 11 and a cutterhead 12, which is rotatable relative to frame 11 on main bearings 14. Drive motors 16 power the relative rotation of cutterhead 12. Cutterhead 12 carries a plurality of roller cutters 18 which are preferably disposed in a plurality of cutter supports 20 in radial array. Located on the sections between adjacent cutter supports 20 are muck openings 22, which are preferably radially disposed slots, that communicate with cutterhead chamber 23. Cutterhead chamber 23 includes a plurality of muck buckets 25 which load tunneled material onto conveyors to be described in detail below. Adjacent muck openings 22 are a plurality of drag picks 24 which are useful in softer mucking conditions to guide muck into muck openings 22. Screw conveyor bypass 43 is substantially centrally located in cutterhead 12 and accommodates the bypass of muck from the screw conveyor described in detail below.
Referring now to FIGS. 1 and 4 through 5, a plurality of articulation cylinders 26 are attached to clevises 28 of cutterhead 12 by pins 30 such that extension and retraction of articulation cylinders 26 causes angular movement of the face of cutterhead 12 relative to the plane of the tunnel work face. A plurality of thrust cylinders 32, fixedly attached between cutterhead 12 and tunneling machine 10, provide relative forward thrusting of cutterhead 12 to cut the tunnel work face.
Tunnel lining segments 34, which are segmented linings known to those skilled in the art, are erected within the cut tunnel by segment erector 36, segment erector tracks 38, and rollers 40. All of the above elements, and the method of lining erection, will be recognized as well known in the art.
Referring to FIGS. 1, 3a-c, 6 and 7, the elements allowing operation of tunneling machine 10 in the "open mode" and the "closed mode" will now be described. It should be noted that FIG. 1 shows the "closed mode" of operation. It is to be understood that in the "open mode" tunneling machine 10 operates in self-supporting earth and rock formations and in the absence of significant quantities of pressurized or unpressurized water. It will be understood that, in the "closed mode", tunneling machine 10 can operate in a tunnel in which water pressure, for example, is between about 1.5 and 2 bars. It also will be understood that in the "closed mode" the slurry system is a low flow slurry system in which the pressurized slurry is used only to stabilize the tunnel face, and is not a muck transporting means. In this low flow slurry system muck is extracted from the cutterhead chamber by a screw conveyor and discharged through low volume pressure lock with positive control of the slurry back pressure, which does not require the high capacity muck transportation pumps and large diameter pipe lines of slurry systems known in the art. As will be described below, the fluid balance required for support of the tunnel face (to prevent ground settlement or the creation of excessive voids around the tunnel lining) is achieved by adding a minimal amount of water to the tunnel work face in order to control the face, to fluidize the muck and to reduce cutterhead torque.
Located within cutterhead chamber 23, directly behind cutter supports 20 and roller cutters 18, are screw conveyor 42 and belt conveyor 44. Screw conveyor 42 is permanently oriented at this location, however, belt conveyor 44 is retractable from cutterhead chamber 23 for the "closed mode" configuration of the tunneling machine 10, and is extendable into cutterhead 12 for the "open mode" configuration of tunneling machine 10 in which hard rock is transported along belt conveyor 44. In addition to retraction of belt conveyor 44 in the "closed mode", a bulkhead 45 is securely attached to cutterhead 12, thus sealing cutterhead chamber 23 in an air and liquid tight manner, except for an opening 47 through which screw conveyor 42 passes. Note that screw conveyor 42 is sealed integrally with the opening 47 in the bulkhead 45 in order to maintain pressurization. The bulkhead 45 thus allows pressurization of cutterhead chamber 23. The other end of screw conveyor 42 is connected to pressure lock 46 such that pressurization is maintained.
Referring specifically to FIG. 3a, the "closed mode" configuration is shown in which screw conveyor hopper 49 is disposed on the screw conveyor 42 at an angle to channel tunneling material into screw conveyor 42. Note that belt conveyor 44 has been retracted into cutterhead chamber 23. Referring now to FIG. 3b, the "open mode" of operation is shown in which belt conveyor 44 is extended into cutterhead chamber 23, along with belt conveyor hopper 51. In this "open mode" screw conveyor hopper 49 has been removed for collection of tunneled material by the belt conveyor hopper 51.
In an alternate embodiment of the present invention, screw conveyor hopper 49 and belt conveyor hopper 51 are replaced by convertible hopper 53. Convertible hopper 53 has a swinging chute 55 pivotally attached thereto. Convertible hopper 53 allows collection of tunneled material by either screw conveyor 42 in the "closed mode" or belt conveyor 44 in the "open mode" without the need for interchanging screw conveyor hopper 49 and belt conveyor hopper 51. Belt conveyor 44 need only be retracted or extended and bulkhead 45 added or removed for tunnel boring machine 10 to operate in the "open mode" and the "closed mode", respectively. Specifically, swinging chute 55 is pivoted by swing cylinders known in the art (not shown) such that swinging chute 55 is in position A to channel tunneled material into screw conveyor 42 in the "closed mode". Swinging chute 55 is oriented in position B to channel tunneled material into belt conveyor 44 in the "open mode". Note that FIG. 3c shows the "open mode" of operation because belt conveyor 44 is present.
Referring specifically to FIGS. 1, 6 and 7, secondary conveyor 48 is located at the end of belt conveyor 44 remote from cutterhead 12 for removal of rock from the tunnel in the "open mode". Secondary conveyor 48 is also oriented such that it communicates with dewatering screw 50, located in the watering tank 52, for removal of solids on secondary conveyor 48 in the "closed mode".
The following elements all pertain to both of the "closed mode" modes of operation of tunneling machine 10 diagrammatically shown in FIGS. 6 and 7. Connecting dewatering tank 52 to screw conveyor 42 is pressure lock 46. Pressure lock 46 provides an air and liquid tight connection in order to maintain pressure within cutterhead chamber 23 and the tunnel work face to provide a closed system. Pressure lock 46 will be described in greater detail below. Thus, material transported from cutterhead 12 by screw conveyor 42 is removed through pressure lock 46. Optional water line 56 (FIGS. 6 and 7) maintains water in pressure lock 46 to avoid discharging of the pressurized contents of screw conveyor 42 into a void with consequent severe pressure fluctuations.
After passing through pressure lock 46, the material is discharged, at atmospheric pressure, into a dewatering system including dewatering tank 52. The material is removed from the water medium by dewatering screw 50. Sloping dewatering screw 50 elevates and drains the muck, which is then transferred to secondary conveyor 48 for removal from the tunnel. All of the above elements are common to the "closed mode" shown in FIG. 6, which also includes a secondary refining system to be described, and to the "closed mode" of FIG. 7 which does not include the aforesaid secondary refining and separation system.
More specific reference is next made to FIG. 6, in which the "closed mode" system with a secondary refining and separation system is shown. Connected to the downstream end of screw conveyor 42 is hydrocyclone line 58, which is part of an optional hydrocyclone system. Screw conveyor 42 is enlarged at its upper section to provide a passage for the portion of the flow that carries the finer particles which do not separate or by gravity. These "fines" are thus passed along hydrocyclone line 58 to hydrocyclone 60. Hydrocyclone line 58 includes back pressure control valve 62 that maintains the desired pressure within screw conveyor 42, and thus within cutterhead chamber 23. Hydrocyclone 60 communicates with fines separator 64 having vibratory screen 66 which empties material onto secondary conveyor 48 for removal from the tunnel. Separator 64 also includes a return line 68 which feeds into hydrocyclone line 58. Additionally, dewatering line 70 connects dewatering tank 52 to separator 64, thus providing additional material separation from dewatering tank 52.
The main fluid discharge from hydrocyclone 60, containing the very fine solids fraction, is delivered to an optional bentonite adding system including mixing tank 72 along fluid discharge line 76 . The solid fraction, after being combined with water or fluidized bentonite, is pumped back to the face as makeup slurry through reservoir/accumulator 74. The fluid discharge line 76 interconnecting cyclone 60 and mixing tank 72 contains a density meter 78 and a flow meter 80 in a manner known in the art. Mixing tank 72 receives water through water line 82 having flow meter 84. Mixing tank 72 receives fluidized bentonite along line 86 which includes flow meter 88. Line 86 receives bentonite from mixing tank 90 and hopper 92. The density of the mixture in mixing tank 72 is monitored by density meter 94. The above bentonite addition system and hydrocyclone system of the optional secondary refining and separation system shown in FIG. 6 serve two purposes: the introduction of fresh bentonite to the face for enhanced stabilization and the more complete removal of fines material in the hydrocyclone.
The secondary refining and separation system of FIG. 6 also comprises a reservoir-accumulator 74 which receives fresh fluidized bentonite through reservoir-accumulator line 96. However, if the optional secondary refining and separation system is not present, as shown in FIG. 7, reservoir/accumulator 74 then receives its input from dewatering line 70 and from a water or bentonite supply source on line 96 (not shown) mixed to supply the correct density. In both embodiments, reservoir/accumulator 74 is interconnected with air compressor 98 having pressure control valve 100. From reservoir/accumulator 74 a low flow makeup slurry, either with or without bentonite, is pumped into cutterhead chamber 23 at a pressure substantially equal to and offsetting the prevailing ground water or earth pressure. Thus, reservoir/accumulator 74 is interconnected with cutterhead chamber 23 by slurry inlet pipe 102, which is in pressure communication with the tunnel face through cutterhead 12. Slurry inlet pipe 102 also includes a flow meter 104.
The pressure at the tunnel face depends on maintaining the appropriate back pressure in the discharge side of the system, specifically at screw conveyor 42 and pressure lock 46, and on controlling the supply side flow, specifically at reservoir accumulator 74, to match the discharge flow. Thus, reservoir/accumulator 74, maintained at a constant preset pressure and connected to slurry inlet pipe 102, substantially eliminates the effects of pressure surges. The level of the air fluid interface in reservoir/accumulator 74 is monitored and the output of the pump on reservoir/accumulator line 96 is varied to maintain the desired level of the air-fluid interface within a desired fixed range.
Reservoir/accumulator 74 also provides a means for maintaining tunnel face pressure during shutdowns. Because the pressure requirement at the tunnel face varies with local conditions, the "closed mode" of FIGS. 6 and 7 are configured to cope with such pressure variations.
Referring next to FIGS. 8 through 11, a first embodiment of pressure lock 46 is disclosed. In this embodiment, pressure lock 46 is a cycling device in housing 105 having a pair of chambers A and B which are alternately filled with slurry, sealed off, and evacuated to prevent the high pressure in screw conveyor 42 from communicating with the atmospheric pressure in dewatering tank 52. The material passed from screw conveyor 42 into one side or the other pressure lock 46 is subsequently discharged at atmospheric pressure into dewatering tank 52. Optionally, the two chambers are alternately flooded with water from water line 56 during the operation to avoid discharging of the pressurized contents of screw conveyor 42 into a void, thus avoiding severe pressure fluctuations.
Pressure lock 46 includes inlet gate 106, which is swung from one side of pressure lock 46 to the other by inlet gate cylinder 108. Outlet gate 110 is likewise swung from one side of pressure lock 46 to the other by outlet gate cylinder 112. Dividing pressure wall 114 in housing 105 partitions pressure lock 46 into chamber A and chamber B.
In operation, for example, inlet gate 106 is positioned over chamber B such that material from screw conveyor 42 falls into chamber A. At this time, outlet gate 110 is positioned under chamber A so that the material falls into chamber A. Note that chamber A has previously been filled with water from water line 56. Next, inlet gate 106 moves across pressure lock 46 to be over chamber A. Outlet gate 110 then moves across pressure lock 46 to rest under chamber B (FIG. 11). In this manner, the material in chamber A passes out of pressure lock 46 into dewatering tank 52, and chamber B, which previously was filled with water from water line 56, now receives additional material from screw conveyor 42. The above process is repeated in a cyclical manner as the discharge progresses.
Now referring to FIGS. 12 through 14, an alternate embodiment of pressure lock mechanism according to the present invention is described in detail. Specifically, pressure lock 46' provides substantially continuous material delivery into dewatering tank 52 from screw conveyor 42. Thus, pressure lock 46' is considered less likely than a gate type lock to cause pressure pulsations at the tunnel face. Additionally, pressure lock 46', being a carousel type delivery system, provides a lower profile that enables tunneling machine 10 to also have a lower profile.
Pressure lock 46' is comprised of carousel housing 116 integrally formed of top 118, bottom 120 and side 122. In top 118 is entrance 124 which is connected to screw conveyor 42 by entrance chute 126. In bottom 120 is exit 128 which communicates with exit chute 130 leading to dewatering tank 52. It is to be noted that entrance 124 in top 120 and exit 128 in bottom 120 are located on opposite sides of carousel housing 116. Located directly under entrance 124 is secondary exit 132 in bottom 120. Slidably mounted over secondary exit 132 is secondary exit plate 134. Secondary exit cylinders 136 are interconnected with secondary exit plate 134 to cause sliding engagement and disengagement of secondary exit plate 134 with secondary exit 132.
Axle 138 passes through the vertical axis of carousel 116 and fixedly secures a plurality of partitions 140 radially disposed within carousel 116 to form wedge shaped chambers 142. Relative rotation of axle 138, partitions 140 and chambers 142 (either clockwise or counterclockwise) relative to carousel housing 116 is caused by motor 144.
During operation of pressure lock 46', material from screw conveyor 42 passes through entrance chute 126 and entrance 124 in top 118 of carousel housing 116. The material thus enters one of a plurality of chambers 142 between adjacent radial partitions 140. Optionally, the chamber 142 that receives material through chute 121 can, prior thereto, be filled with water from water line 56 in order to minimize pressure fluctuations at the tunnel face and within cutterhead 12. It is to be noted that wedge-shaped chamber 142 and the material received through entrance chute 126 are in a pressurized state due to the integral connection of screw conveyor 42, entrance chute 126 and carousel housing 116. Actuation of motor 144 causes the chamber 142 containing the material to rotate with partitions 140 and axis 138. When this chamber 142 containing material reaches exit 128 in bottom 120, the material passes through exit 128 into exit chute 130 and is deposited in dewatering tank 52. Note that dewatering tank 52 is at atmospheric pressure, and thus exit chute 130 is also at atmospheric pressure. After this particular chamber 142 has dumped the material, it can, at this time, optionally be filled with water from water line 56 as stated above. The above process continues in a cyclical mode.
Optionally, if it is desired to bypass pressure lock 46', secondary exit cylinders 136 are retracted, thus slidably removing secondary exit plate 134 from secondary exit 132. Additionally, motor 144 is deactivated. Now, material passing from screw conveyor 42 through entrance chute 126 and entrance 124 in top 118 will pass through carousel housing 116 and secondary exit 132 in bottom 120. In this manner, material will pass directly through carousel housing 116 and can then be transported by secondary conveyor 148 out of the tunnel without processing in dewatering tank 52.
While particular embodiments of the present invention have been described in some detail hereinabove, changes an modifications may be made in these embodiments without departing from the spirit and scope of the invention as defined in the following claims. | A tunneling machine convertible between a "closed mode" and an "open mode" of operation, having a rotatable cutterhead with muck openings communicating with a pressurizable cutterhead chamber and a pressure maintenance system to stabilize the tunnel workface when operating in the "closed mode". In the "closed mode" low slurry flow is employed as a liquid pressure balance solely to support the unstable tunnel face. Low slurry flow is supplied through a pressure bulkhead sealing the cutterhead chamber and pressurized conveyor means through the bulkhead removes tunneled material from the cutterhead chamber. A pressure lock connected to the pressurized conveyor means transfers tunneled material to dewatering and reservoir/accumulator means operated at substantially atmospheric pressure. Slurry, with at least most of the solids removed, is recycled to the slurry inlet at a controlled low flow rate matching the rate of removal of tunneled material and slurry from the tunnel face so the otherwise unstable tunnel face is maintained stable. In the "open mode" of operation, for use in boring a self-stabilizing tunnel face, the pressure bulkhead is removed and a second conveyor, such as a belt conveyor, is disposed adjacent to the "closed mode" conveyor to withdraw cuttings from the cutterhead chamber. | 4 |
This application claims priority of PCT application PCT/CH2006/000489 having a priority date of Oct. 6, 2005, the disclosure of which is incorporated herein by reference.
TECHNICAL FIELD
The invention relates to a method for weaving a ribbon on a needle ribbon weaving machine and to a needle ribbon weaving machine.
BACKGROUND OF THE INVENTION
A method and a needle ribbon weaving machine for weaving a ribbon of the type initially mentioned are known from DE 40 09 455A. The method described there for producing a ribbon on a needle ribbon weaving machine takes place by means of two closed weft needles operating contradirectionally, the ribbon being woven by both weft needles as a result of insertion into a common shed. The heads of the contradirectionally inserted weft thread loops are secured on each ribbon side by means of wales which are formed in each case from an auxiliary thread and which are located at the two edges of the ribbon. The disadvantage, then, is that always two weft thread loops have to be inserted into a common shed, so that, in the event of a shed change, two weft thread loops, that is to say four weft thread portions, have to be tied in simultaneously. The stability of the ribbon to be produced is impaired as a result. There are also no variations of any kind possible, since closed weft needles having guide loops on which a weft thread is always arranged are used.
SUMMARY OF THE INVENTION
The object of the invention is to improve the method for weaving a ribbon on a needle ribbon machine having two simultaneously and contradirectionally operating weft needles.
Since only that weft which is presented to one of the two weft needles is inserted, any desired weft sequence is possible. Not just two weft threads may be introduced simultaneously into the shed, as is afforded in the prior art, but, in particular, the weft threads may be inserted alternately from ribbon sides to ribbon sides, so that, in the event of each shed change, only one weft thread loop is inserted. Furthermore, it is possible, moreover, to present weft threads even of changing color and quality to the weft needles. This not only affords a mechanically improved quality of the ribbon produced, but the pattern possibility is also increased.
On each ribbon side, the weft thread loops may be knitted together with themselves, or, they may be knitted by means of an interlaced auxiliary thread.
For the needle ribbon weaving machine serving for carrying out the method, it is essential that an individually operating thread lifter for presenting a weft thread to a weft needle designed to be open is present on each ribbon side.
A preferred design of the weft needle which has a fork, arranged on the needle shank, for receiving the weft thread, and also a guide slot for the weft thread, said guide slot running along the needle shank to just short of the fork.
BRIEF DESCRIPTION OF THE DRAWINGS
Exemplary embodiments of the invention are described in more detail below by means of the drawings showing the weaving region of a needle ribbon weaving machine in various weaving phases, specifically the tie-off of an inserted weft thread loop by means of an auxiliary thread in FIGS. 1 to 4 and the tie-off of inserted weft thread loops without an auxiliary thread in FIGS. 5 to 7 . In the drawings:
FIG. 1 shows the weaving region during the beating-up of a weft thread loop inserted by the left weft needle in a diagrammatic illustration;
FIG. 2 shows the weaving region of FIG. 1 during the insertion of a weft thread loop by means of the right weft needle;
FIG. 3 shows the weaving region of FIG. 2 with an inserted weft thread loop and before the tie-off of the latter;
FIG. 4 shows the weaving region of FIG. 3 during the beating-up of the weft thread loop inserted by the right weft needle and during the presentation of the weft thread to the left weft needle;
FIG. 5 shows the weaving region during the beating-up of a weft thread loop inserted by the right weft needle;
FIG. 6 shows the weaving region of FIG. 5 during the insertion of a weft thread loop inserted by the left weft needle;
FIG. 7 shows the weaving region of FIG. 6 during the interlacing of the inserted weft thread loop.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIGS. 1 to 4 show the weaving region of a needle ribbon weaving machine with two contradirectionally driven weft needles 2 a , 2 b which insert weft threads 4 a , 4 b into a shed 6 . In the shed 6 formed from warp threads 8 , the weft threads are beaten up at the beating-up edge 10 by means of a reed 9 , thus giving rise to the ribbon 12 .
The weft needles 2 a , 2 b are in each case open needles, i.e. they have at the front end of a needle shank 14 a , 14 b a fork 16 a , 16 b , into which the respective weft thread 4 a , 4 b is introduced by means of a thread lifter 18 a , 18 b movable up and down. The weft needles 2 a , 2 b contain in each case guide slots 20 a , 20 b which run along the needle shank 14 a , 14 b and which reach beyond the forks 16 a , 16 b . The guide slots 20 a , 20 b serve for guiding the weft thread 4 a , 4 b when the weft thread is not inserted into the shed 6 , and for making it easier to introduce into the fork 16 a , 16 b with the aid of the respective thread lifter 18 a , 18 b . The web thread loop 22 a , 22 b inserted in each case is secured by means of an auxiliary thread 24 a , 24 b which is in each case presented to knitting needles 28 a , 28 b by means of a thread guide 26 a , 26 b such that said auxiliary thread is interlaced with the weft thread loops 22 a , 22 b.
In the position shown in FIG. 1 , the left weft needle 2 a has just inserted a weft thread loop 22 a into the shed 6 and has been beaten up at the beating-up edge 10 by means of the reed 11 . By means of the left thread lifter 18 a , the left weft thread 4 a is raised on the fork 16 a of the weft needle 2 a as a result of the raising of the thread lifter 18 a , to an extent such that said left weft thread cannot be grasped by the fork 16 a of the weft needle 2 a . On the right side of the shed, the thread lifter 18 b is lowered and brings the weft thread 4 b into engagement on the fork 16 b of the weft needle 2 b , so that, the latter can insert the weft thread loop 22 b into the open shed 6 , as shown in FIG. 2 . The left weft needle 2 a runs, empty, into the shed, the weft thread 4 a being guided in the guide slot 20 a . When the weft thread loop 22 b has been inserted completely into the shed, as is evident from FIG. 3 , the left knitting needle 28 a grasps the auxiliary thread 24 a and draws the latter through the inserted weft thread loop 22 b and further on through the last loop 30 a of the auxiliary thread 24 a . On the right side, the auxiliary thread 24 b is interlaced with itself, that is to say with its last loop 30 b , without being drawn through a weft thread loop. After this securing of the inserted weft thread loop 22 b by means of the auxiliary thread 24 a , the weft needles 2 a , 2 b leave the shed, and the reed 11 beats up the weft thread loop thus inserted at the beating-up edge 10 . The thread lifter 18 b is then raised again and prevents an engagement of the weft thread 4 b on the fork 16 b of the weft needle 2 b . Instead, by means of the thread lifter 18 a , the weft thread 4 a is brought into engagement on the fork 16 a of the weft needle 2 a , in order, during the next shed opening, to insert a further weft thread loop 22 a from the left ribbon side in a similar way.
FIGS. 5 to 7 show a needle ribbon weaving machine which is constructed similarly to the needle ribbon weaving machine of FIGS. 1 to 4 , and therefore parts identical to the first exemplary embodiment are given the same reference symbols. Reference is made to the relevant statements with regard to FIGS. 1 to 4 . In the exemplary embodiment of FIGS. 5 to 7 , however, no auxiliary threads are used, but, instead, the weft threads 40 a , 40 b are interlaced with themselves. FIG. 6 shows how the weft thread loop 42 a from the weft thread 40 a is inserted into the shed by means of the left weft needle 2 a . After complete insertion, the right knitting needle 28 b grasps the inserted weft thread loop 42 a and draws the latter through the already knocked-over weft thread loop 42 a . During the insertion of the weft thread loop 42 a by means of the weft needle 2 a from the left side of the ribbon, the right weft needle 2 b moves, empty, through the shed. The weft thread 40 b is in this case guided in the guide slot 20 b of the right weft needle 2 b , as may be gathered from FIG. 7 . As soon as the weft needles 2 a , 2 b are drawn back out of the shed, the beating-up of the inserted weft thread loop 42 a by means of the reed 11 at the beating-up edge 10 takes place, as illustrated in FIG. 5 . The shed change is followed by the insertion of the weft thread loop on the right side of the ribbon, the operation taking place in a similar way to the insertion of the weft thread on the left ribbon side.
LIST OF REFERENCE SYMBOLS
2 a Weft needle
2 b Weft needle
4 a Weft thread
4 b Weft thread
6 Shed
8 Warp thread
10 Beating-up edge
11 Reed
12 Ribbon
14 a Needle shank
14 b Needle shank
16 a Fork
16 b Fork
18 a Thread lifter
18 b Thread lifter
20 a Guide slot
20 b Guide slot
22 a Weft thread loop
22 b Weft thread loop
24 a Auxiliary thread
24 b Auxiliary thread
26 a Thread guide
26 b Thread guide
28 a Knitting needle
28 b Knitting needle
40 a Weft thread
40 b Weft thread
42 a Weft thread loop
42 b Weft thread loop | A needle webbing machine which comprises two weft needles ( 2 a, 2 b ) which work simultaneously and in opposite directions on both ribbon sides, in addition to knitting needles ( 28 a, 28 b ) which are arranged on both ribbon sides. A yarn lifter ( 18 a, 18 b ) which works individually and which is used to advance a weft thread ( 4 a, 4 b ) to a weft needle ( 2 a, 2 b ), which is open, is provided on each side of the ribbon in order to improve the production thereof. | 3 |
CROSS REFERENCE TO RELATED APPLICATION
This application is a continuation of application Ser. No. 07/682,750 filed Apr. 9, 1991, now U.S. Pat. No. 5,334,012, which is a continuation-in-part of Ser. No. 07/633,334, filed Dec. 27, 1990, now abandoned.
TECHNICAL FIELD
The present invention relates in general to a combustion chamber which more efficiently burns fuel with fewer undesirable emissions, and in particular to an improved combustion chamber useful for heating aggregate in an asphalt plant.
BACKGROUND ART
No single component is more important in the manufacture of hot mix asphalt than the aggregate dryer and its exhaust system. One problem encountered with the use of such apparatus is pollution in the form of NO x compounds produced by the burner flame. It is known that the formation of NO x compounds may be inhibited by more efficient combustion of the available fuel; reducing the amount of nitrogen in the fuel; reducing the flame temperature; reducing the amount of air available for combustion; and reducing the time that combustion gases spend at elevated temperatures.
It is common in the steam generation industry to lower flame temperature by recirculating flue gas to the burner and thereby reducing NO x emissions. This reduction in flame temperature is further augmented by staged combustion in which the flame is initially oxygen poor (and therefore cooler) and is charged with additional oxygen a short time later to complete combustion. Multiple stages are preferably utilized to obtain the best results.
Experience has taught, however, that methods useful in the steam industry for reducing the formation of NO x compounds are not applicable to equipment used in the production of asphaltic products, such as aggregate dryers. This is because the two processes utilize different types of flames to provide heat and because aggregate dryers generally are of a shorter dimension unsuitable for implementing staged combustion techniques having multiple stages. Steam generation plants typically utilize lengthy staged combustion and a flame characterized as long and lazy. Lengthy, multiple staged combustion set-ups and long, lazy flames cannot be used in aggregate dryers because aggregate dryers typically provide a smaller combustion area than do steam plants.
The recirculation of gases in rotary heating equipment for purposes other than to reduce the level of NO x is known in the art. U.S. Pat. No. 4,190,370 discloses a drum mixer having a temperature control system for regulating the temperature of the asphalt-aggregate mix by varying the flow of hot gases through the drum mixer. The system is also disclosed in connection with an aggregate dryer. The temperature control system withdraws gases exiting the drum before they pass through a baghouse and recirculates them to an input manifold on the drum mixer. This recirculation system reduces the temperature of the burner flame and the energy required to heat the gases within the drum mixer, but does not suggest any effect on NO x emissions.
Reissue U.S. Pat. No. Re. 29,496 discloses another rotary heating device in which combustion gases are recirculated from the outlet of a drum mixer to a burner assembly located at the inlet of the drum mixer. The recirculation gases are passed through a heating or a cooling heat exchanger before being routed to the burner. This recirculation scheme is said to provide a somewhat isothermal air flow to the burner and to allow more energy efficient operation, but the patent does not discuss any reduction in either flame temperature or flame length. Nor does the patent suggest that the scheme operates to reduce NO x emissions.
Other examples of rotary heating devices incorporating various gas recirculating schemes are disclosed in U.S. Pat. Nos. 3,963,416; 4,143,972; 4,309,113; 4,332,478; 4,600,379; and 4,892,411. However, none of these recirculation methods are directed to the reduction of NO x emissions.
Therefore, there remains a need for an improved rotary heating device for use in the production of asphaltic paving materials having reduced NO x emissions, and in particular for a combustion chamber which consumes fuel in a manner which results in fewer NO x emissions.
SUMMARY OF THE INVENTION
The present invention solves the above-discussed need in the art by providing an improved combustion chamber and a method of flowing gases through a combustion chamber which enhances the mixing of fuel and air to allow more efficient operation, to promote greater flame stability and to reduce the level of NO x emissions created in the combustion process.
Generally described, the present invention comprises a combustion chamber having improved heating efficiency and reduced NO x emissions, comprising an enclosure defining a first end and a second end, and capable of having a main current of gases flowing from the first end to the second end, the internal cross section of the enclosure including a throat positioned at the first end and having a first cross-sectional area; a first expansion adjacent and interior to the throat, having a cross-sectional area greater than the first cross-sectional area of the throat for promoting a vortexlike motion of gas flow within the enclosure which runs contrary to the main current in part of the first expansion; and a second expansion adjacent and interior to the first expansion having a cross-sectional area greater than the cross-sectional area of the first expansion for promoting a vortexlike motion of gas flow within the enclosure which runs contrary to the main current in part of the second expansion.
The present invention may also provide more than two expansions in the cross-sectional area of the chamber and is particularly useful when used in connection with aggregate dryers, but can also be used with other heating apparatus.
In another aspect of the present invention, there is provided a method for increasing heating efficiency and reducing NO x production in a combustion chamber, comprising the steps of introducing a main current of combustion gases into a first cross-sectional area; passing the main current of gases from the first cross-sectional area into a second cross-sectional area having a cross-sectional area greater than the first cross-sectional area such that a first portion of gases is separated from the main current and directed to run contrary to the main current in part of the second cross-sectional area; and passing the main current of gases from the second cross-sectional area into a third cross-sectional area having a cross-sectional area greater than the second cross-sectional area such that a second portion of gases is separated from the main current and is directed to run contrary to the main current in part of the third cross-sectional area.
This method may also provide more than two expansions in the cross-sectional area and is particularly useful with combustion chambers used in connection with aggregate dryers, but can also be used with other heating apparatus.
Accordingly, it is an object of the present invention to provide an improved combustion chamber.
Another object of the present invention is to provide a combustion chamber which minimizes the amount of NO x emissions associated with its operation.
It is yet another object of the present invention to provide a combustion chamber which reduces the production of NO x compounds by influencing the How of gases through the chamber.
A further object of the present invention is to provide a combustion chamber having flow characteristics which increase the proportion of the volume of the chamber having turbulent flow.
A still further object of the present invention is to provide a combustion chamber which provides the formation eddy currents within the combustion chamber to improve heating efficiency, promote flame stability and reduce NO x emissions.
Yet another object of the present invention is to provide an aggregate dryer having reduced NO x emissions.
Still another object of the present invention is to provide a method for increasing the heating efficiency and reducing the production of NO x of a combustion chamber.
These and other objects, features and advantages of the present invention will become apparent from a review of the following detailed description of the disclosed embodiment and the appended drawings and claims.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a preferred embodiment of the present invention.
FIG. 2 is a schematic diagram of the device shown in FIG. 1.
FIG. 3 is a cross-sectional view of the combustion chamber of FIG. 1.
FIG. 4 is a diagrammatic cross-sectional view of the combustion chamber showing the flow pattern of gases through the chamber.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to the drawings, in which like numerals indicate like parts, throughout the several views, FIG. 1 shows a counter-flow aggregate dryer 10 adjacent a baghouse 12 and a virgin aggregate bin 14. The aggregate is fed by a conveyor belt 18 from the bin 14 for delivery into the dryer 10 in a manner well known in the art. The baghouse 12 filters gases which have passed through the dryer 10, also in a conventional manner.
Referring now to FIGS. 1 and 2, the dryer 10 includes an elongate drum 20 rotatably mounted on a support frame 22. Pivotally attached at one end of the support frame 22 are a pair of support legs 24. Attached at the other end of the support frame 22 are a pair of extendable support legs 26. The length of the legs 26 may be adjusted by various methods known in the art, but preferably hydraulically. In their unextended configuration, the legs 26 are generally of a shorter length than the legs 24, which are adjacent to the aggregate feed conveyor 18. In this configuration, the drum 20 is mounted at an angle inclined from horizontal. As the legs 26 are extended, the angle of inclination of the drum 20 is reduced. However, it is desirable that the drum 20 always be maintained at some inclined angle so that material fed into the drum by the conveyor 18 will feed down the length of the drum 20 due to the affect of gravity as the drum is rotated. The adjustability of the legs 26 therefore provides a means for controlling the rate at which material will feed down the length of the drum 20 at a particular rate of rotation of the drum.
Located at the lower end of the dryer 10 is a flame source, such as a conventional gas burner 28. The burner 28 projects a flame 30 having a temperature of between about 2,200° and 3,000° F. into a refractory combustion chamber 32, shown in more detail in FIG. 3. A discharge manifold 31 is located between the refractory combustion chamber 32 and the drum 20 for discharge of heated aggregate to a hot mix pugmill coater 34 located adjacent the dryer. The hot mix coater 34 is of known construction and operation, as shown in U.S. Pat. No. 4,616,934, incorporated herein by reference.
The pugmill coater 34 is positioned adjacent to and below the combustion chamber 32 with its longitudinal axis sloping with respect to horizontal. The lower end 29 of the pugmill coater is disposed below and adjacent to the discharge manifold 31 so that the dried aggregate from the dryer 10 falls by gravity directly into the pugmill coater 34. Recyclable material may also be introduced into the pugmill coater by a recycle conveyor 27, in a manner well known in the art and recovered fines may also be introduced through a particle return duct 53, described below. Conventional apparatus for heating and conveying liquid asphalt to the pugmill coater is also provided.
Referring now to FIGS. 3 and 4, the refractory combustion chamber 32 is a stepped chamber designed to aid the mixing of recirculated gases and reduce NO x emissions, as explained below. The combustion chamber 32 is preferably a steel shell 33 lined with a castable refractory material 35 such as Greencast 97-L available from A. P. Greencast. Mexico, Mo. To provide a more turbulent flame 30, the chamber 32 is configured to have a stepped configuration including a reduced diameter throat 36 at a first or exterior end 38 of the chamber located closest to the burner 28 and a step 37 located downstream of the throat. The throat has an annular surface 21 which forms a flowpath for gases through the throat. A radially extending, annular connecting surface 23 connects the throat to the expanded cross-sectional area provided by the step 37.
Referring further to FIG. 3, the following measurements set forth in Table 1 illustrate the preferred dimensions of the interior of the chamber 32. It should be noted however, that it is the general relative dimensions provide the preferred flow characteristics.
TABLE 1______________________________________ ApproximateDistance Measurement (ft)______________________________________A 8.0B 1.0C 1.0D 1.5E 2.0F 1.0G 8.0H 0.5I 0.5J 0.5K 3.5______________________________________
The reduced throat and stepped construction allows, on its own, for decreased NO x production with increased efficiency and drying capabilities. The chamber construction provides enhanced mixing of fuel and air which results in a more turbulent, more stable flame. The shape of the chamber also creates back-swirl or eddy currents 15 and 16 as shown in FIG. 4 which aid in the mixing of combustion gases.
Referring further to FIG. 4, there is shown a main current 17 of gases entering the combustion chamber through the throat 36. A beveled surface 39 is provided at the throat entrance to reduce the effect of the sudden contraction of the throat on the flow of gas. The beveled surface 39 eliminates the sharp corner that would otherwise be present to induce vortice formation along the inner surface of the throat. Such vortices would promote better mixing of gases, but would also increase the pressure drop through the throat to an undesirable level for the present embodiment. The throat of the embodiment shown in FIG. 3 has a pressure drop of about 8 inches water gauge. It will be understood, however, that for some applications the beveled surface 39 may be omitted. Additionally, for some applications, a beveled surface (not shown) may be provided on the throat exit to alter flow characteristics. As shown in FIG. 4, an angle Z exists between the throat surface 21 and the connecting surface 23 and has a value of about 90°. It will be understood that the angle Z is not necessarily a 90° angle and need not form a sharp corner at this point. The most important characteristic of the chamber is the provision of successive enlargements of the cross-sectional area to promote the formation of vortexlike currents which run contrary to the main current to allow better mixing of the combustion gases. However, by making the throat surface 21 a beveled surface or inclining the surface 23 and thus reducing angle Z preferably not to less than about 7°, vortice formation along the connecting surface 23 may also be induced. Likewise, it will also be understood that the step 37 need not be a 90° corner.
In the embodiment of FIG. 4, the velocity of the main current 17 of gases increases during passage through the throat 36. Upon exiting the throat, the main current 17 encounters successive enlargements of the cross-sectional area of the chamber 32 and experiences a decrease in velocity. When the main current encounters a first expansion V of the cross-sectional area created by the step 37 wherein the diameter of the chamber increases from E to 2D+E (shown in FIG. 3), a portion of the flow separates from the main current into a first set of eddy currents 15 which are drawn toward the perimeter of the chamber and run contrary to the main current in the outer parts of the first expansion V. As the main current progresses toward a second expansion W of the cross-sectional area downstream and adjacent the step 37 wherein the diameter increases from 2 D+E to G, an additional portion of the flow separates from the main current into a second set of eddy currents 16 which are drawn towards the perimeter of the chamber in the second area of expansion and run contrary to the main current in this area. It will be appreciated that the flow characteristics of the main current may be different along the length of the chamber, as the eddy currents formed in each area serve to alter the flow of the main current.
The formation of eddy currents is known to occur whenever a flow encounters a sudden increase in cross-sectional area. It has been observed, however, that by shaping the interior of the chamber such that the cross-sectional area of the chamber is increased in successive steps rather than all at once, the efficiency of the chamber is increased. For example, it has been experienced that a combustion chamber made in accordance with the measurements of Table 1 enhances heating efficiency by allowing more complete combustion. Visual observations of a flame within a combustion chamber made in accordance with Table 1 indicates more complete combustion as evidenced by the chamber having a translucent volume without distinguishable, individual flame edges. It is believed that this increase in flame stability and efficiency results from enhanced formation of eddy currents, as shown in FIG. 4, which result from the combination of the reduced diameter throat and stepped configuration of the chamber.
To further reduce NO x emissions, gases may be introduced to the end of the flame to act in a "quenching" manner or to provide an abbreviated version of staged combustion. The steel shell 33 of the chamber 32 is surrounded by an annular duct 40 which is supplied with recirculated gases in a manner described below. A series of quenching holes or nozzles 42 extend through the refractory material 35 to communicate with the interior of the chamber 32 at a second end 41 of the chamber which opens to the drum 20. The nozzles 42 provide a "quenching ring" for introducing cooler exhaust gases to cool and reduce the length of the flame or may be used as conduits for adding air for staged combustion. As will be explained further, the annular duct 40 is preferably adapted to conduct recirculated gases through the nozzles 42 and direct them generally toward the center of the chamber at a velocity sufficient to penetrate the flame 30. This further promotes turbulence and mixing of the recirculated gases with the end of the flame 30 and reduces the temperature and length of the flame. Experience has taught that a velocity of about 10,000 feet per minute is suitable and may be obtained using a fan or blower generating a pressure of about 16 inches H 2 O through thirty-six uniformly spaced 2 inch diameter nozzles.
The heated gases from the burner 28 pass from the chamber 32 into the drum 20 to heat and dry the virgin aggregate 14. An exhaust manifold 46 is provided at the upper end of the drum 20 for conducting gases from the drum 20. The exhaust manifold 46 is connected to a separator duct 48 for conducting gases and suspended particulate matter (such as small aggregate particles) away from the exhaust manifold. The duct 48 leads to a conventional cyclone separator 50 located above the drum 20 for removal of particulate matter, such as aggregate fines, from the exhaust gases. The removed particulate matter is conducted to the pugmill coater 34 by a particle return duct 53 which leads from the bottom of the cyclone separator 50 to the pugmill coater 34. A baghouse duct 54 conducts the separated gases to the baghouse 12 for further particulate removal.
The baghouse 12 is of a design well known in the art and includes an internal filter chamber 56 within which extend a number of fiber filter collectors in the form of filter bags (not shown). Air flow through the baghouse 12 is provided by an exhaust fan 58 having an inlet duct connected to a plenum chamber of the baghouse (not shown). The output of the exhaust fan 58 is connected to an exhaust stack 64 which opens to the atmosphere. A recirculating duct 66 is connected to the exhaust stack 64 for routing an amount of the exhaust gases through the recirculating duct. A manual diverter damper 68 is provided on the exhaust stack 64 to route a percentage of the exhaust gases to the recirculating duct 66 according to the damper setting. A modulating control damper 70 is provided on the recirculating duct to vary the flow of gases through the recirculating duct 66 in proportion to the fuel flow to the burner 28. The modulating control damper 70 receives a control signal from a burner controller (not shown) of a type which is well known in the art for controlling the amount of fuel and air introduced to the burner 28. The modulating controller may be calibrated and operated to provide a flow consistent with the values set forth in Tables 2 and 4.
The exhaust gases routed to the recirculating duct 66 may be routed to the burner 28 or to the quenching nozzles 42, or both. A "Y" duct 72 is provided along the recirculating duct 66 to permit the desired routing of the exhaust gases, as explained below.
The recirculating duct 66 is split at the "Y" duct 72 into a primary exhaust gas recirculating ("EGR") feed duct 74 and a quenching EGR feed duct 76. Manual control dampers 78 and 80 are provided on the primary EGR feed duct 74 and the quenching EGR feed duct 76, respectively. Manipulation of the dampers 78 and 80 allows the desired amount of exhaust gas to be routed through each of the ducts 74 and 76. A primary ambient air duct 82 having a manual control damper 84 and a staging ambient air duct 86 having a manual control damper 88 are provided just downstream of the "Y" duct 72 for introducing ambient air to the primary air feed duct 74 and the quenching air feed duct 76, respectively. The flow rates of gases through each of the ducts 74, 76, 82 and 86 are preferably monitored utilizing conventional pitot tube apparatus (not shown) downstream of the dampers 78, 80, 84 and 88, respectively.
Additionally, it will be understood that each of the manual control dampers 68, 78, 80, 84 and 88 may be replaced with electronic control dampers, whose operation may be controlled responsive to signals from the pitot tubes, utilizing conventional microprocessor equipment well known in the art for automatic process control.
The contributions of the primary EGR feed duct 74 and the primary ambient air duct 82 are combined at point R to form a primary EGR duct 75. Likewise, the contributions of the quenching EGR feed duct 76 and the staging ambient air duct 86 are combined at point S to form a quenching EGR duct 79. The primary EGR duct 75 extends to a conventional primary air inlet 77 on the burner 28. For combustion to occur, air and fuel must be supplied to the burner 28 in appropriate amounts. Combustion air is defined as the air or gases required for complete combustion of the available fuel. Excess air is defined as the air or gases supplied in addition to the combustion air. Combustion and excess air may be supplied to the burner 28 utilizing the primary EGR duct 75 and/or a tertiary air duct 89. A primary fan 90, and a tertiary fan 94 are provided along each of the respective ducts 75 and 89 to render available the desired amount of gases from each duct. The quenching EGR duct 79 extends via an inlet duct 81 to communicate with the annular duct 40 of the combustion chamber. A quenching fan 92 is provided along the quenching EGR duct 79 to transmit the desired amount of gases through the quenching EGR duct 79. To obtain the maximum flow rates shown in Example 1 below, a 100 horsepower centrifugal fan was utilized for the primary fan 90; a 40 horsepower centrifugal fan was utilized for the quenching fan 92; and a 150 horsepower axial flow fan was utilized for the tertiary fan 89.
The dryer 10 operates as follows. A continuous supply of virgin aggregate is introduced into the drum 20 by the conveyor 18. The flame 30 from the burner 28 provides combustion gases to the refractory combustion chamber 32. These gases exit the drum 20 via the exhaust manifold 48 and are routed to the cyclone separator 50 for removal of particulate matter and then to the baghouse 12 for further removal of particulate matter.
It is noted that gases exiting the baghouse 12 are more humid and at a lower temperature than gases within the dryer 10. The present invention uses these cooler, moister gases emerging from the baghouse 12 to accomplish a reduction in the formation of NO x compounds. The dryer 10 thereby is a conventional counter-flow aggregate dryer except for the novel features described herein.
It is found that combustion efficiency may be improved, and hence NO x production may be reduced, by providing a stepped configuration within the combustion chamber which promotes the formation of eddy currents. It is also found that NO x emissions may be reduced by maintaining a highly turbulent, short flame 30 while reducing the maximum temperature of the flame and the time that the gases spend at a temperature where NO x is readily created. The dryer 10 operates to produce this second set of conditions by taking the gases from downstream of the exhaust fan 58 and recirculating them to the burner 28 via the primary EGR duct 75 and to the end of the flame 30 via the quenching duct 79, as discussed above. While it will be understood that ambient air or gases recirculated from the exhaust manifold 46 may be used, it is preferred to use air recirculated from after the baghouse 12. Additional benefits of using air recirculated from after the baghouse 12 include the elimination of the backflow of excessively hot furnace gases through the primary fan 90 and the quenching fan 92, and the elimination of dust loading from the fans 90 and 92.
A flow of recirculated gases through the primary EGR duct 75 and the quenching duct 79 may be established by the primary fan 90 and the quenching fan 92, respectively. These moister, cooler recirculated gases are routed to the burner 28 by the primary EGR duct 75 and to the end of the flame 30 via the quenching EGR duct 79 which directs gases to the nozzles 42. Introduction of recirculated gases to the burner 28 and the quenching ring 38 reduces the flame temperature, the flame length, and the free oxygen content. These reductions result in a lower rate of NO x production. As stated before, it is preferable to recirculate gases from after the baghouse 12, because the gases are cleaner and less damaging to the blowers 90 and 92. The trade-off for this benefit of cleaner gases is the disadvantage of a more oxygen rich and cooler recirculation gas stream, because baghouse filtration increases oxygen content. It will be understood that a less oxygen rich exhaust gas stream may be obtained by recirculating the exhaust gas from before the baghouse 12. This, however, has the disadvantage of a more dust laden gas stream.
The amount of exhaust gas recirculated is determined as a mass percentage of the "total gases" supplied by the Primary EGR duct 75, the quenching EGR duct 79, and the tertiary air duct 89. Combustion air is the amount of air or gases needed for combustion of the available fuel. Excess air is the amount of air or gases supplied in excess of the combustion air.
In the preferred operation of the dryer 10, all of the combustion air and some of the excess air is supplied by the primary EGR duct 75 in combination with the tertiary air duct 89. In this mode, the quenching EGR duct 79 supplies exhaust gases to the nozzles 42 at a velocity sufficient to penetrate the flame 30.
As stated above, the term "total gases" is defined as the sum of all recirculated gases and fresh air supplied by the primary EGR duct 75, the quenching EGR duct 79, and the tertiary air duct 89. In the preferred operating mode, the contributions and compositions of the various gases and air ducts preferably fall within the following ranges set forth in Table 2.
TABLE 2______________________________________ Approximate % Approximate % by mass in duct by mass which is recir-Duct Description of total gases culated gas______________________________________66 Recirculation 5 to 50 10074 Primary EGR Feed 0 to 95 10082 Primary ambient air 0 to 95 075 Primary EGR 28 to 95 5 to 10076 Quenching EGR Feed 5 to 30 10086 Staging Ambient Air 0 079 Quenching EGR 5 to 30 10089 Tertiary Air 0 to 67 0______________________________________
EXAMPLE 1
The below Table 3 sets forth maximum flow rates anticipated to be utilized to perform tests of a dryer embodying the invention. The results of the planned tests are expected to indicate an average reduction in NO x emissions, as measured at the exhaust stack 64, from approximately 0.024 pounds per ton of aggregate to approximately 0.158 pounds per ton of aggregate.
TABLE 3______________________________________ Actual Actual Maximum Flow Opera- Opera- Rate cubic feet ting ting per min. at Temp PressureDuct Description 60° F. and 1 atm (°F.) (inch H.sub.2 O)______________________________________64 Exhaust to 44,750 250 -5.0Atmosphere66 Recirculation 13,350 250 -5.074 Primary EGR 10,146 250 -5.0Feed82 Primary Ambi- 10,146 ambi- -0.1 entent Air75 Primary EGR 10,680 250 -5.076 Quenching 8010 250 -5.0EGR Feed86 Staging Ambi- 0 ambi- -0.1 entent Air79 Quenching EGR 8010 250 -5.089 Tertiary Air 16,020 ambi- -0.1 ent______________________________________
The above description discloses a mode of operation in which sufficient oxygen is provided to the burner 28 to allow complete combustion. The gases supplied by the quenching nozzles 42 are provided to reduce flame temperature and length. It will be understood, however, that other modes of operation may be practiced to reduce flame temperature and length. For example, the flow rates and the percentage of recirculated gases and fresh air in each duct may be varied to achieve the desired effects. For example, an abbreviated form of staged combustion may be accomplished by supplying insufficient combustion air to the burner. The remaining air required for combustion of the available fuel may then be supplied by the quenching nozzles 42. When operating in the staged combustion mode, the contributions and compositions of the gases and air ducts preferably fall within the ranges given in Table 4:
TABLE 4______________________________________ Approximate % Approximate % by mass in duct by mass which is recir-Duct Description of total gases culated gas______________________________________66 Recirculation 0 to 30 10074 Primary EGR Feed 0 to 95 10082 Primary Ambient Air 0 to 95 075 Primary EGR 28 to 95 0 to 10076 Quenching EGR Feed 0 10086 Staging Ambient Air 5 to 30 079 Quenching EGR 5 to 30 089 Tertiary Air 0 to 67 0______________________________________
It will further be noted that the novel design of the combustion chamber 32 is capable of reducing NO x emissions independent of the introduction of recirculated gas or staged combustion. This result occurs because of the superior mixing of fuel and air obtained by the geometry of the chamber. Thus, the duct 40 and nozzles 42 may be eliminated in some applications. However, if recirculated gases are provided, the chamber geometry aids in mixing recirculated gases with fuel and air.
While the foregoing description relates to a counter-flow aggregate dryer, it will also be understood that the foregoing invention may also be utilized to reduce NO x emissions in connection with parallel flow dryers drum mixers, and other heating apparatus.
The foregoing description relates to preferred embodiments of the present invention, and modifications or alterations may be made without departing from the spirit and scope of the invention as defined in the following claims. | A combustion chamber having improved heating efficiency and reduced NO x emissions includes a reduced diameter throat and a stepped configuration within the chamber. The chamber configuration encourages efficient combustion to reduce NO x production by promoting the formation of eddy currents within the chamber. A method for increasing heating efficiency and reducing NO x production is provided and involves passing combustion gases through such a combustion chamber. | 4 |
RELATED APPLICATIONS
The present invention was first described in a notarized Official Record of Invention on Jan. 14, 2010, that is on file at the offices of Montgomery Patent and Design, LLC, the entire disclosures of which are incorporated herein by reference.
FIELD OF THE INVENTION
The present invention relates generally to riding lawn mowers, and in particular, to a trimmer type attachment for such lawn mowers.
BACKGROUND OF THE INVENTION
Many people spend countless hours maintaining and beautifying their lawns and landscape. As a matter of pride and personal expression, these people manicure their grass and often plant and maintain flowers, shrubs, bushes, and trees all for the sake of enhancing the aesthetic qualities of their property. On properties with large areas of grass to cut, riding mowers are very popular. They allow their users to cut relatively large areas of grass in a minimal amount of time while allowing the rider to sit in comfort.
One (1) problem associated with riding mowers is that, due to their size, they are not very adept at cutting close to objects such as fences, buildings, trees and the like. This usually requires the user to go back afterwards with a string type trimmer This, in turn, negates the riding mower benefits of being able to sit down and save time. Accordingly, there exists a need for a means by which grass trimming duties can be accomplished at the same time grass is being cut by a conventional riding mower.
Various attempts have been made to provide trimmer attachments for riding mowers. Examples of these attempts can be seen by reference to several U.S. patents, including U.S. Pat. Nos. 3,782,085; 5,035,107; 5,598,689; 6,094,896; 6,343,461; 6,779,325; and 6,986,238. However, none of these designs are similar to the present invention.
While these devices fulfill their respective, particular objectives, each of these references suffer from one (1) or more of the aforementioned disadvantages. Many such devices are not universally mountable for a variety of mower models. Also, many such devices do not provide a full range of desirable adjustability and manipulation of the trimmer head position during use. Furthermore, many such devices are not readily operated and manipulated by a lawn mower rider from their seated position. In addition, many such devices do not include a simple, renewable power source. Accordingly, there exists a need for an electric trimmer attachment for lawn mowers without the disadvantages as described above. The development of the present invention substantially departs from the conventional solutions and in doing so fulfills this need.
SUMMARY OF THE INVENTION
In view of the foregoing references, the inventor recognized the aforementioned inherent problems and observed that there is a need for an electric trimmer attachment for lawn mowers which is universally attachable and adjustable while providing a simple means for powering and operating the trimmer attachment while riding the lawn mower. Thus, the object of the present invention is to solve the aforementioned disadvantages and provide for this need.
To achieve the above objectives, it is an object of the present invention to provide an electrically operated trimmer attachment mountable to a rider-based grass cutting device. The apparatus comprises an electric cutting head, a guide arm, and a caster. The cutting head comprises a trimmer type cutting assembly including an automatically advancing string cutter. The guide arm supports the cutting head and the caster facilitates motioning of the guide arm and cutting head along a ground surface.
Another object of the present invention is to attach to a mowing deck surface of a riding style lawn mower. The apparatus comprises a mounting bracket attached to the deck surface with a plurality of fasteners. The mounting bracket is connected to a vertical support pole which further supports a positioning mechanism attached to a main support arm. The main support arm attaches to the cutting head and allows a user to control the position of the cutting head.
Yet still another object of the present invention is to allow the user to manipulate and operate the apparatus while seated in a seat of the lawn mower. The main support arm attached to the positioning mechanism extends from the cutting head at a lower end upwards towards the seat and further comprises an operating handle adapted for ergonomic gripping by the user.
Yet still another object of the present invention is to allow a user to control rotational motion of the cutting head by motioning the operating handle. The handle and guide arm attach to the positioning mechanism which comprises a plurality of housing sections attached to the vertical support pole. A middle housing structure of the positioning mechanism is rotatable with respect to the support pole.
Yet still another object of the present invention is to allow a user to selectively lock and secure the main support arm in a plurality of discrete positions with a locking pin and a plurality of keyed slots.
Yet still another object of the present invention is to facilitate use of the trimmer attachment in a conventional manner by the user while seated in the riding mower and while the riding mower is turned off or otherwise not moving.
Yet still another object of the present invention is to provide electrical power to the apparatus by a connection cable and electrical power connector which draw electrical power from the riding mower.
Yet still another object of the present invention is to allow a user to quickly disconnect the electrical power connector from the riding mower as needed.
Yet still another object of the present invention is to prevent unauthorized or unintentional operation of the apparatus by including a keyed ignition switch.
Yet still another object of the present invention is to ensure safety of the user by comprising a seat occupancy verification switch which automatically cuts power to the apparatus if the user is not seated in the riding mower.
Yet still another object of the present invention is to allow a user to selectively control the supply of power to the apparatus while seated with a dash-mounted switch. The dash-mounted switch allows the user to cut the electrical power supply to the apparatus when the apparatus is not being utilized.
Yet still another object of the present invention is to provide a method of utilizing the device that provides a unique means of obtaining an instance of the apparatus, attaching the apparatus to the mower deck of the riding mower with the mounting bracket, connecting the electrical power connector to a battery of the riding mower, sitting in the seat of the riding mower, operating the riding mower in a conventional manner, utilizing the operating handle to manipulate the position of the cutting head from the seat when the riding mower is stopped, utilizing the dash-mounted switch to activate the blades of the cutting head to provide a trimming function while the riding mower is stopped, locking the position of the cutting head as desired using the locking pin and the plurality of keyed slots, and continuing to utilize the riding mower and trimmer attachment in conjunction until a desired lawn maintenance task is complete.
Further objects and advantages of the present invention will become apparent from a consideration of the drawings and ensuing description.
BRIEF DESCRIPTION OF THE DRAWINGS
The advantages and features of the present invention will become better understood with reference to the following more detailed description and claims taken in conjunction with the accompanying drawings, in which like elements are identified with like symbols, and in which:
FIG. 1 is an environmental view of an electrically operated trimmer apparatus for rider-based grass cutting means 10 , according to the preferred embodiment of the present invention;
FIG. 2 is a section view of a positioning mechanism 55 taken along a line I-I (see FIG. 1 ), according to the preferred embodiment of the present invention;
FIG. 3 is a section view of a mounting bracket 90 taken along a line II-II (see FIG. 1 ), according to the preferred embodiment of the present invention;
FIG. 4 is a section view of a cutting head 30 taken along line III-III (see FIG. 1 ), according to the preferred embodiment of the present invention;
FIG. 5 is a section view of a handle 60 taken along line IV-IV (see FIG. 1 ), according to the preferred embodiment of the present invention; and,
FIG. 6 is an electrical schematic diagram of the major electrical components as used upon the electrically operated trimmer apparatus for rider-based grass cutting means 10 , according to the preferred embodiment of the present invention.
DESCRIPTIVE KEY
10
electrically-operated trimmer apparatus for rider-based
grass cutting means
15
trimmer apparatus
20
rider-based grass cutting device
25
lawn cutting apparatus
30
cutting head
31
lip
35
guide arm
40
caster
41
fastener
45
self-advancing string cutter
50
main support arm
51
secondary support arm
52
main support aperture
53
secondary support aperture
54
pin
55
positioning mechanism
60
handle
65
cable trigger
66
pivot point
67
trigger aperture
68
attachment knot
70
user
75
seat
80
vertical support pole
81
upper spacer
82
lower spacer
85
mowing deck surface
90
mounting bracket
95
first fastening system
100
connection cable
105
vegetation
110
cutting path arc
115
lower housing structure
116
spool assembly
120
middle housing structure
125
upper housing structure
130
lower bearing raceway
135
upper bearing raceway
145
cover cap
150
upper control arm
155
azimuth control wheel
160
keyed slots
165
locking pin
166
pin guide
170
control cable
175
linear spring
176a
upper guard
176b
lower guard
177a
upper shaft
177b
lower shaft
178
anti-rotation pin
179
spring
180
fastening hardware
185
electrical power connector
190
upper support surface
195
lower support surface
200
upper washer
205
upper nut
210
lower washer
215
lower nut
220
battery
225
keyed ignition switch
230
seat occupancy verification switch
235
transformer
240
overcurrent protective device
245
dash-mounted switch
250
motor
251
shaft
252
lock nut
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The best mode for carrying out the invention is presented in terms of its preferred embodiment, herein depicted within FIGS. 1 through 6 . However, the invention is not limited to the described embodiment and a person skilled in the art will appreciate that many other embodiments of the invention are possible without deviating from the basic concept of the invention, and that any such work around will also fall under scope of this invention. It is envisioned that other styles and configurations of the present invention can be easily incorporated into the teachings of the present invention, and only one particular configuration shall be shown and described for purposes of clarity and disclosure and not by way of limitation of scope.
The terms “a” and “an” herein do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced items.
Referring now to FIG. 1 , an environmental view of the electrically-operated trimmer apparatus for rider-based grass cutting means 10 , according to the preferred embodiment of the present invention, is disclosed. The electrically-operated trimmer apparatus for rider-based grass cutting means (herein described as the “system”) 10 comprises a trimmer apparatus 15 that is mounted and electrically connected with a rider-based grass cutting device 20 such as a riding mower, a riding lawn tractor, or a riding garden tractor with a lawn cutting apparatus 25 . The system 10 comprises a cutting head 30 (also see FIG. 4 ) that trims vegetation 105 such as grass, weeds or the like. The system 10 also comprises an operating handle 60 located at a distal end of a length adjustable secondary support arm 51 such that it can be easily reached and operated by a user 70 when positioned upon a seat 75 of the rider-based grass cutting device 20 . An underside surface of the handle 60 comprises a cable trigger 65 which enables a positioning mechanism 55 to be unlocked for manipulation purposes. The positioning mechanism 55 is supported by a height adjustable vertical support pole 80 that is attached to a mowing deck surface 85 by use of a mounting bracket 90 (also see FIG. 3 ). Electric power for the cutting head 30 is provided by a connection cable 100 , whose additional details will be described in greater detail herein below. These features allow for the system 10 to trim vegetation 105 as defined along a cutting path arc 110 .
Referring now to FIG. 2 , a section view of the positioning mechanism 55 taken along a line I-I (see FIG. 1 ), according to the preferred embodiment of the present invention, is disclosed. The vertical support pole 80 extends from the mowing deck surface 85 and comprises a tubular body which comprises exterior threads and further includes a threaded cover cap 145 which enables access to an internal portion. The vertical support pole 80 supports said positioning mechanism 55 , which further comprises a lower housing structure 115 , a middle housing structure 120 , and an upper housing structure 125 with the use of a lower bearing raceway 130 and an upper bearing raceway 135 . As such, the lower housing structure 115 and the upper housing structure 125 remain stationary with respect to the vertical support pole 80 . This allows motion input from an upper control arm 150 which attached to the positioning mechanism 55 diametrically opposite from the secondary support arm 51 and further connects to the operating handle 60 (see FIG. 1 ) to provide rotational input control. Said motion will then be vectored to a main support arm 50 and the cutting head 30 . An upper spacer 81 is positioned between the upper bearing raceway 135 and an azimuth control wheel 155 which creates a fixed gap and gives additional stability to the positioning mechanism 55 . Likewise, a lower spacer 82 is positioned between the lower bearing raceway 130 and the azimuth control wheel 155 for stability. The spacers 81 , 82 encompass the vertical support pole 80 and are fabricated from a material such as rubber, yet other materials may be utilized without limiting the scope of the system 10 .
These aforementioned components are held captive against the vertical support pole 80 via a set of fastening hardware 180 such as washers and nuts. The fastening hardware 180 also adjusts the vertical position of the positioning mechanism 55 upon the vertical support pole 80 . By loosening the fastening hardware 180 the positioning mechanism 55 is able to be slidably positioned to a desired height with respect to the user 70 upon the vertical support pole 80 and by subsequently tightening said fastening hardware 180 into the desired position said positioning mechanism 55 is fixed into the desired position.
The specific position of the secondary support arm 51 can be locked in place via a lower housing structure 115 which is physically affixed to the vertical support pole 80 . Such fixation is accomplished via a series of keyed slots 160 in the azimuth control wheel 155 which engage a locking pin 165 . This locking pin 165 can be withdrawn to allow for freedom of movement via the cable trigger 65 which is connected to a control cable 170 working against a linear spring 175 . The locking pin 165 is directed through a pin guide 166 which is further attached to an internal wall for stability. The pin guide 166 also houses the linear spring 175 which is attached to the locking pin 165 on a distal end and attached to the control cable 170 on an opposing proximal end.
The support arms 50 , 51 are also telescopingly adjustable which provides a length adjustment means to the system 10 . The main support arm 50 comprises a diameter slightly larger than the secondary support arm 51 and enables said main support arm 50 to slidably engage said secondary support arm 51 . The main support arm 50 comprises a main support aperture 52 and the secondary support arm comprises a plurality of corresponding secondary support apertures 53 . The user 70 may align the apertures 52 , 53 and insert a pin 54 which is preferably a common detent pin or a cotter pin to lock the support arms 50 , 51 into a desired position.
Finally, the connection cable 100 is routed through the middle housing structure 120 and down the support arms 50 , 51 to the cutting head 30 . An electrical power connector 185 is provided at the end of the connection cable 100 to allow for the system 10 to be quickly disconnected from the rider-based grass cutting device 20 (also see FIG. 1 ) should the need arise.
Referring now to FIG. 3 , a section view of the mounting bracket 90 taken along a line II-II (see FIG. 1 ), according to the preferred embodiment, is disclosed. The mounting bracket 90 is mounted against the mowing deck surface 85 via use of a pair of first fastening system 95 such as screws, washers, nuts, or the like although other fastening means such as snap fasteners, keyed locks, and the like, could be used with equal effectiveness and as such, should not be interpreted as a limiting factor of the present invention. Such a first fastening system 95 allows for removal of the system 10 from the rider-based grass cutting device 20 should it not be needed at a later time. The vertical support pole 80 penetrates an upper support surface 190 and is additionally supported by a lower support surface 195 . As motion of the vertical support pole 80 is provided via the positioning mechanism 55 (as shown in FIG. 2 ), the vertical support pole 80 is held captive at the mounting bracket 90 . Such capture is accomplished via an upper washer 200 and an upper nut 205 against the upper support surface 190 , and a lower washer 210 and a lower nut 215 against the lower support surface 195 . Note that the surface of the vertical support pole 80 is to be threaded at this point to accomplish such fastening.
Referring now to FIG. 4 , a section view of the cutting head 30 taken along line III-III (see FIG. 1 ), according to the preferred embodiment of the present invention, is disclosed. The cutting head 30 provides the trimming means to the system 10 in a similar nature to those conventionally available and would be supplied with a spool assembly 116 , and a motor 250 . The cutting head 30 comprises a circular dome-shaped body and is fabricated from durable materials such as rubber, plastic, or the like. The cutting head 30 includes an internally positioned motor 250 which is supplied with power via the connection cable 100 . The motor 250 rotates a shaft 251 which concurrently connects said motor 250 to the spool assembly 116 . The spool assembly 116 is used to house the trimming line and comprises a self-advancing string cutter 45 similarly to common weed trimmers.
The cutting head 30 also comprises a guide arm 35 (see herein below) which assists said cutting head 30 while in use. A lower perimeter edge of the cutting head 30 comprises an integral lip 31 which provides an attachment surface to a pair of three-hundred-sixty degree (360°) casters 40 . The casters 40 are mounted to opposing sides of the lip 31 by fasteners 41 . The casters ride along the surface of the vegetation 105 which enables the cutting head 30 , along with the guide arm 35 , to remain level while in use.
The guide arm 35 is positioned between the cutting head 30 and the main support arm 50 . The guide arm 35 is suspended from a proximal lower surface of the main support arm 50 and comprises an upper guard 176 a , a lower guard 176 b , an upper shaft 177 a , a lower shaft 177 b , and a spring 179 . The guide arm 35 provides a shock absorbing or damping means to the system 10 as said system 10 is being utilized. The guards 176 a , 176 b and shafts 177 a , 177 b comprise a tubular shape which enable the connection cable 100 to be routed from the main support arm 50 to the motor 250 . The upper guard 176 a is attached to a lower surface of the main support arm 50 and the lower guard 176 b is attached to an upper intermediate surface of the cutting head 30 . The diameter of the lower guard 176 b is slightly smaller than the diameter of the upper guard 176 a to enable said lower guard 176 b to slidably travel within said upper guard 176 a . The guards 176 a , 176 b eliminate debris from an internal portion of the guide arm 35 . The shafts 177 a , 177 b are positioned within the guards 176 a , 176 b and are encompassed by the spring 179 which provides a recoiling means to the guide arm 35 . The upper shaft 177 a is also attached to a lower surface of the main support arm 50 and the lower shaft 177 b is also attached to an upper intermediate surface of the cutting head 30 . Likewise, the diameter of the lower shaft 177 b is slightly smaller than the diameter of the upper shaft 177 a to enable said lower shaft 177 b to slidably travel within said upper shaft 177 a . A distal outer surface of the upper shaft 177 a comprises a pair of opposing anti-rotation pins 178 which engage a proximal portion of the lower shaft 177 b to provide compliance with rough surfaces in the z-axis and further keep the shafts 177 a , 177 b centered and vertical during use.
Referring now to FIG. 5 , a section view of the handle 60 taken along line IV-IV (see FIG. 1 ), according to the preferred embodiment of the present invention, is disclosed. An underside surface of the handle 60 comprises the cable trigger 65 which enables the user 70 to manipulate the positioning mechanism 55 . The cable trigger 65 pivots about a pivot point 66 by the user 70 depressing said cable trigger 65 inwards. The control cable 170 is attached with an attachment knot 68 or similar attachment means to a trigger aperture 67 . As the cable trigger 65 is depressed the control cable 170 tightens which will pull the locking pin 165 out from the keyed slot 160 to further enable the user 70 to manipulate the positioning mechanism 55 as above-mentioned.
Referring now to FIG. 6 , an electrical schematic diagram of the major electrical components as used upon the system 10 , according to the preferred embodiment of the present invention, is disclosed. Electrical power is obtained from the battery 220 of the rider-based grass cutting device 20 . Access control is provided by a keyed ignition switch 225 to prevent unauthorized or unintentional operation. Next, power control is routed through a seat occupancy verification switch 230 to ensure that the user 70 is present in the seat 75 (as shown in FIG. 1 ) of the rider-based grass cutting device 20 . A transformer 235 is then provided, if needed, to adjust the voltage level of the battery 220 to that of the cutting head 30 . The secondary output of the transformer 235 is protected via an overcurrent protective device 240 such as a fuse, circuit breaker, or the like. The last electrical element to control power flow to the system 10 is that of a dash-mounted switch 245 located on the dash area of the rider-based grass cutting device 20 . The dash-mounted switch 245 allows the user 70 to control the operation of the system 10 such that it is energized only when needed. Connection to the electrical circuitry is made via the electrical power connector 185 which allows for the rapid connection and disconnection of a motor 250 associated with the cutting head 30 . The aforementioned circuitry is of a series connected nature, and as such, allows great latitude in how it is constructed and configured. This operational sequence is intended to identify important control elements associated with the system 10 and the specific interconnection configuration is not intended to be a limiting factor of the present invention.
It is envisioned that other styles and configurations of the present invention can be easily incorporated into the teachings of the present invention, and only one particular configuration shall be shown and described for purposes of clarity and disclosure and not by way of limitation of scope.
The preferred embodiment of the present invention can be utilized by the common user in a simple and effortless manner with little or no training. The system 10 would be constructed in general accordance with FIG. 1 through FIG. 6 . Regardless of the actual origination, the trimmer apparatus 15 would be installed via a physical mechanical connection of the mounting bracket 90 and first fastening system 95 as well as an electrical interconnection as depicted in FIG. 4 . It is known that various differences would be needed to fit exact specific models of rider-based grass cutting device 20 , but that overall generalities of construction and interconnection would remain the same. After the system 10 is installed both mechanically and electrically, it is ready for operation and use.
During use of the system 10 , the user 70 would remain in the seat of the rider-based grass cutting device 20 and cut grass using the lawn cutting apparatus 25 in a conventional manner. Should an area be approached that requires specialize trimming, the user would stop the rider-based grass cutting device 20 , but remain in a seated position. Next, the user would activate the dash mounted switch 245 with one (1) hand while holding the operating handle 60 with the other. The user would engage the cable trigger 65 on the operating handle 60 such that the cutting head 30 can be swung back and forth along a cutting path arc 110 to cut the vegetation 105 . The cutting head 30 is supported in this operation by the guide arm 35 and the casters 40 . The trimmer apparatus 15 could be locked in place via the locking pin 165 in the keyed slots 160 of the azimuth control wheel 155 with the cutting head 30 in an operating mode for cutting in a linear fashion by the movement of the entire rider-based grass cutting device 20 . Such operation is advantageous when cutting vegetation 105 along a straight or near straight obstacle such as a fence, building, flower bed or the like.
Such operation and cutting of vegetation 105 continues until not needed anymore. At such a point in time, the system 10 is deactivated using the dash-mounted switch 245 . Such operation continues in a cyclical manner until all vegetation 105 cutting and trimming is complete.
The foregoing descriptions of specific embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention and method of use to the precise forms disclosed. Obviously many modifications and variations are possible in light of the above teaching. The embodiment was chosen and described in order to best explain the principles of the invention and its practical application, and to thereby enable others skilled in the art to best utilize the invention and various embodiments with various modifications as are suited to the particular use contemplated. It is understood that various omissions or substitutions of equivalents are contemplated as circumstance may suggest or render expedient, but is intended to cover the application or implementation without departing from the spirit or scope of the claims of the present invention. | An electric trimmer attachment for lawn tractors comprises an attachable apparatus for use with existing lawn tractors which provides trimmer capabilities. The apparatus comprises a mounting bracket, an arm, and a line trimmer. The mounting bracket provides a means for removably securing the device to a deck of an existing mower. The arm comprises a gooseneck arm attached to the bracket, which extends outwards. An outside end portion of the arm comprises a line trimmer with an electric motor and features such as automatic line advancement and safety controls. The motor is powered via a converter or battery pack on the mower. The arm provides an arc-shaped rotating motion to the trimmer. | 0 |
The present application is filed pursuant to 35 U.S.C. 371 as a U.S. National Phase application of International Patent Application No. PCT/IN2009/000670, which was filed Nov. 20, 2009, claiming the benefit of priority to Indian Patent Application No. 167/DEL/2009, which was filed on Jan. 29, 2009. The entire text of the aforementioned applications is incorporated herein by reference in its entirety.
TECHNICAL FIELD
This invention relates to a wool care composition comprising pyrethroid insecticide, a copolymer and a solvent wherein the said copolymer binds with the solvent and pyrethroid insecticide. The wool care composition can be an aerosol spray composition for protection (insect proofing) of pure or blended woollen items, fur and feathers lined garments, and other keratinous items from various species of insect pests, more specifically but without implying any limitation thereto, to protect such items, during their storage, use and transport from various types of insect species of woollen pests.
BACKGROUND
Woollen articles made of pure (100%) wool fibres or blended with natural or synthetic fibres like polyester, viscose rayon, cotton, etc. or both in different proportion such as apparel, carpet, durries, felt etc. and fur-feather lined garments are highly susceptible to insect damage, and are frequently damaged or destroyed by various insect species of wool pests in commercial, industrial and domestic stores and also during their use and transport. Sometimes this damage result into colossal loss to the stored woollen items. Unprotected keratinous items such as sikhar trophies, animal skins, upholstered furniture and stuffed animal museum specimens are also damaged by these wool pests.
The wool pests are of two types, carpet beetles and clothes moths which commonly found damaging woollen and fur and feathers items. The carpet beetle species are Anthrenus flavipes, Anthrenus verbasci, Anthrenus coloratus, Anthrenus oceanicus, Attagenus fasciatus, Attagemis cyphonoides, Attagemis lobatus, Attagemis indicus and Attagenus birmanicus . The clothes moths species are Tinea transhtcens, Tinea pellionella, Tinea dubiella and Tineola bisselliella . These pests cause maximum damage during their larval stage to the woollen, fur-feather lined items and other keratinous items in stores or when these items are left unattended for longer period and also during their use and transport.
Conventionally naphthalene or Paradichlorobenzene is known in the art to be used to protect woollen and fur-feather lined articles from insect damage during their storage. But these above compounds are ineffective against clothes moths and thus unable to provide protection to the woollen items as established by Abbott & Billings of USA in 1935 and published their work in the Journal of Economic Entomology on page 493-495 as entitled “Further work showing that Paradichlorobenzene, Naphthalene and cedar oils are ineffective as repellents against clothes moth”. The ineffectiveness of the naphthalene balls in protection of woollen articles from insect pests is also confirmed by the present inventors.
Further disadvantage of naphthalene balls being in solid forms have to be kept as such with a layer or two of the garment thereby providing limited protection through its vapours. Also, these balls cause discolouring of the woollen items when-placed directly on the woollen item for long period. These balls provide no protection to the woollen items, fur and feather lined garments and other keratinous items from insect pests when kept in open, as balls require airtight container. Thus, there is a need to develop new antibacterial drugs with novel mechanism of action.
Application No. 2313/CHENP/2007 discloses a pharmaceutical formulation for delivery in aerosol or spray form, comprising a liquefied propellant gas, a solid particulate pharmaceutically active agent and a dispersing agent, wherein the dispersing agent is fused to the surface of particles of the pharmaceutically active agent.
U.S. Pat. No. 5,178,872 discloses an insecticidal and/or acaricidal and/or nematicidal composition having a rapid efficacy and residual activity which comprises a mixture of a poorly water-soluble organophosphorus insecticide and/or acaricide and/or nematicide and/or a poorly water-soluble carbamate insecticide and/or acaricide which have been microencapsulated in water-insoluble polymer coatings with a dispersing agent used in forming a microcapsule part, with a poorly water-soluble pyrethroid insecticide and/or acaricide emulsified or suspended in water with the above-mentioned dispersing agent used in forming a flowable part.
US 2008/0090780 A1 discloses a storage stable, efficacious pesticide formulation is provided that is dilutable by the user and contains azadirachtin (AZA) and a pyrethrin or pyrethroid (PYR), and optionally an aprotic solvent and non-ionic, substantially water-free emulsifier. A sufficient amount of the PYR is provided to complex with the AZA A on opposite sides of the molecular structure thereof, thereby preventing rearrangement of the AZA A molecule in the presence of moisture that would result in hydrolysis and decomposition of AZA A. The AZA-PYR combination is sufficiently chemically stable such that less than 10% of the AZA A is decomposed when the formulation is subjected to an accelerated aging test for 30 days at 40° C. in a sealed container. The molar ratio of PYR to AZA A is preferably within the range of 0.5/1-10.5/1, more preferably within the range of 1.5/1-7/1, and most preferably with the range of 3/1-6/1. A solvent, when provided, should be in the range of about 70% to about 90% by weight based on the weight of the formulation, and the emulsifier should be within the range of about 0% to about 20%.
WO 1997/00610 discloses an insect-attracting insecticidal aerosol spray composition containing an insect-attracting effective amount of 1 to 10% w/w of lauric acid, d-limonene, orange oil or mixtures thereof. The composition provides a long lasting barrier protection. It maintains the attractancy for a period of 13 weeks or more.
A method of treating carpet and other textile products comprising animal fibres or a mix of synthetic fibres and animal fibres is disclosed in WO/1997/023682. The method includes applying a formulation to carpet or other textile products. The formulation comprises compounds effective against the larvae of a range of Coleopteran species and a chemical which is effective against the larvae of a range of Lepidopteran species. The fluorosurfactant compound can offer only partial control of the larvae of a range of Lepidopteran species. The formulation can be added to the carpet, yarn, loose fibre or other textiles during raw-wool scouring, dyeing, tapescouring, chemsetting or continuous carpet treatment.
Microcapsule for smart textile materials, containing an active product and with reactive groups, with the objective of chemically binding the microcapsules to the fibres is disclosed in WO 2006/117702. The microcapsules contain active products such as PCM (phase change materials), or can be of controlled release of products such as fragrances, essential oils, antibacterial and others with the objective to add specific functional properties to the textile materials. They can be applied by padding and spraying followed by thermo fixation. In case of products such as knitwear the application process can also be by exhaustion process, given that the microcapsules acquire affinity towards the fibres and react with the fibres during the process. The chemical bond of the controlled release microcapsules with the fibres confers them a higher resistance to washing than the existing microcapsules glued to the fabric by printing or padding.
WO 2006/107905 discloses pesticide concentrates are provided containing an emulsifier that is an EPA list 4 inert and is a polyglycerol fatty acid ester, a sorbitan fatty acid ester or a combination thereof, a pesticide and a solvent that is either a EPA list 3 inert of acetyl ester, EPA list 4 inert of a methyl fatty ester, an acetyltributyl citrate, white mineral oil or a combination thereof. The pesticide can be a water-insoluble synthetic pyrethroid, natural pyrethrum, channel blocking insecticide, acetylcholinesterase inhibitor, oxadiazine, organophosphate, neonicotinoid insecticide, thiamethoxam, imidacloprid, acetamiprid, thiacloprid, clothianidin, nitenpyran, insect growth regulator, juvenile hormone mimic, fermentation insecticide, plant oil insecticide, acaracide, miticide, fungicide, herbicide and combinations thereof. The pesticide concentrate is diluted with a hydrocarbon solvent, a white mineral oil or a combination thereof and mixed with water. A corrosion inhibitor is added to form a stable water-in-oil emulsion in conjunction with a propellant to make a ready-to-use aerosol for home, garden and public health pest control.
Thus, there is a need to develop a new insecticidal composition for protection of woollen articles made of pure (100%) wool fibres or blended with natural or synthetic fibres like polyester, viscose rayon, cotton, etc. or both in different proportion such as apparel, carpet, durries, felt etc. and fur-feather lined garments that are highly susceptible to insect damage, and are frequently damaged or destroyed by various insect species of wool pests in commercial, industrial and domestic stores and also during their use and transport.
OBJECTS OF THE PRESENT INVENTION
The primary object of the present invention is to provide aerosol spray solution composition which provides highly effective protection to woollen items and other keratinous articles, from various insect species of wool pests i.e. both against carpet beetle types as well as against clothes moth type of insect pests throughout period of their storage, use and transport.
Another primary object of the present invention is to provide an aerosol spray solution composition which can be applied easily on the woollen items, fur and feathers lined garments and other keratinous goods at industry commercial and domestic stores for at least two years.
The objective of present invention is to provide low volatility and dry-cleaning fastness aerosol spray-solution.
Yet another primary object of the present invention to provide an aerosol spray solution composition which causes no stain or any colouring/decolouring when sprayed on woollen items and other keratinous items.
Another object of the present invention is to provide a aerosol spray solution composition which is effective against pests at different stages of their life cycle such as egg, larva and adult.
Further object of wool care aerosol spray solution composition is to provide spray solution which is such that the fabrics, garments sprayed with this solution when put on by humans do not cause any allergy to the wearer of the garment or to the person who sprays the solution.
Still further object of wool care spray solution composition is to provide insecticide spray solution which restricts the evaporation of the solvent isopropyl alcohol or mineral turpentine oil (MTO) or white spirit which is otherwise highly volatile-thereby ensuring that the concentration of insecticide in the solution remains constant during storage.
Yet further object of wool care aerosol spray composition is to provide insecticide spray solution which even sprayed on the woollen items forms a thin film over the surface of the woolen items, which retains insecticide for longer duration.
Still further object of wool care aerosol spray composition is to provide insecticide spray solution which when sprayed does not in any way alter the overall texture or appearance of the woollen garments fur and feather lined goods and other keratinous items.
Further another object of wool care aerosol spray solution is to provide spray which is behaviorally acceptable with pleasant fragrance to the user.
Yet further object of wool care aerosol spray solution is chemical loading of only required dose at industry level on finished fabric or garments and other keratinous items so that wastage of the insecticide solution could be avoided.
Another object of the wool care aerosol spray solution is for application of just sufficient chemical on the finished woollen fabrics at industry level to avoid application of insecticide for insect proofing at various fabric manufacturing stages such as dye bath and last scouring, etc so that water discharge from industry should be free from insecticide pollutant. This can be environmentally beneficial.
Yet another object of wool care aerosol spray solution is to be used easily in the ready to use aerosol spray having a hydrocarbon propellant, or by manually operated sprayer.
Further object of the wool care aerosol spray solution is that whereas the present spray solution can be uniformly sprayed on to the surface of the garment and provides uniform protection to the garment when kept in layers.
SUMMARY OF THE INVENTION
The present invention provides a wool care composition comprising of a pyrethroid insecticide (0.01-0.5% v/v); at least a copolymer (10-25% v/v); a solvent (70-85% v/v); and optionally a fragrance or a mixture of fragrances (1-5% v/v). It also provides a wool care composition comprising pyrethroid insecticide (0.01-0.5% v/v), a copolymer mixture comprising acrylic acid and butyl acrylate (10-25% v/v); and mineral turpentine oil as solvent (70-85% v/v), wherein said acrylic acid and butyl acrylate binds with said mineral turpentine oil and pyrethroid insecticide to enable prolonged storage of wool for at least 60 months. The pyrethroid insecticide used is preferably deltamethrin or permethrin.
The present invention further provides a wool care composition further comprising 20-30% v/v of at least a propellant.
These and other features, aspects, and advantages of the present subject matter will become better understood with reference to the following description and appended claims. This Summary is provided to introduce a selection of concepts in a simplified form. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter.
DETAILED DESCRIPTION
The present relates to a wool care composition comprising a pyrethroid insecticide (0.01-0.5% v/v); at least a copolymer (10-25% v/v); a solvent (70-85% v/v); and optionally a fragrance or a mixture of fragrances (1-5% v/v). The copolymer in the composition of the present invention, binds with the solvent and pyrethroid insecticide to enable prolonged storage of wool for at least 60 months.
In an embodiment of the present invention, the composition comprises a pyrethroid insecticide (0.01-0.5% v/v); a copolymer (10-25% v/v); and a solvent (70-85% v/v); wherein said copolymer binds with the solvent and pyrethroid insecticide to enable prolonged storage of wool for at least 60 months.
In another embodiment of the present invention, the pyrethroid insecticide is a class of synthetic pyrethroid selected from deltamethrin and permethrin. The copolymer used in the composition is acrylic acid and butyl acrylate. Further in another embodiment, the copolymer of acrylic acid and butyl acrylate is in the ratio of 1:3 v/v.
In another embodiment, the solvent used in the composition of the present invention is selected from a group consisting of isopropyl alcohol, mineral turpentine oil (MTO) and white spirit, preferably, mineral turpentine oil.
In yet another embodiment, the fragrance used in the composition is selected from Alpha amyl cinnamic aldehyde, Dimetol, Terpeneol, Citronellol, Cedarwood oil, Lemon oil, Benzyl salicylatde, Tonalid, Ethyl vanillin, Cyclamen aldehyde, sandal wood oil and creosote.
The composition of the present invention can be formulated as a solution, with or without propellant.
In one embodiment, the wool care composition of the present invention further comprises of 20-30% v/v of at least a propellant, which forms another embodiment of the invention. This propellant is selected from a group consisting of C3-C5 alkanes or a mixture thereof. In a preferred embodiment, the propellant comprises of propane (6-12% w/v), n-butane (50-55% w/v) and isobutane (25-39% w/v).
In another preferred embodiment of the present invention, a wool care composition comprises pyrethroid insecticide (0.01-0.5% v/v), a copolymer mixture comprising acrylic acid and butyl acrylate (10-25% v/v); and mineral turpentine oil as solvent (70-85% v/v), wherein said acrylic acid and butyl acrylate binds with said mineral turpentine oil and pyrethroid insecticide to enable prolonged storage of wool for at least 60 months. The pyrethroid insecticide is preferably deltamethrin or permethrin.
The present invention provides a wool care aerosol spray solution composition, an effective amount of which can be sprayed, to kill various species of wool pests. Highly effective-insecticide, synthetic pyrethroid (s) is used as an agent for control of the wool insects and pests in this solute composition. The wool care aerosol spray solution incorporates emulsifier/copolymers and odours/fragrances which are then dissolved with 70-85% v/v of isopropyl alcohol or Mineral turpentine oil (MTO) or white spirit, to which is added a synthetic pyrethroid insecticide such as permethrin, cypermethrin, fenvalerate, deltamethrin, lambda-cyhalothrin or any mixture these insecticides, preferably deltamethrin or permethrin in the range of 0.01-0.5% v/v. The solution of the above chemical solution composition can be uniformly sprayed on to woollen items for providing protection from various species of insects and pests. Co polymer used binds the mineral turpentine oil/white spirit due to the higher viscosity and has the synergic effect of maintaining the concentration of the insecticide in the solution and remains ready for use even after prolonged storage. The copolymer forms a thin film that binds the insecticide and solvent MTO and spread evenly over the garment surface retaining the insecticide for longer period. Thus the woollen garments remained protected for about 60 months of unattended storage after the spray of this insecticide. The copolymer prevents deep penetration because of its high viscosity into the woollen fabric making available the insecticide at the very surface of the fabric, allowing no ingress to wool insects and pests. Odours/fragrances are advantageously selected in such a way that they enhance the repellent activity of the composition against the insect pests and at the same time it make more acceptable to the user as having pleasant smell.
The propellant is advantageously selected in such a way that it provides the desired pressure for uniform delivery of the wool care aerosol spray solution while spraying on the woollen items. Preferred propellants according to the invention are alkanes containing 3 to 5 carbon atoms, such as propane, n-butane, iso-butane, n-pentane and iso-pentane, n-butane and propane are particularly preferred for ready to use aerosol can.
The present invention relates to an improved aerosol spray composition for high effective protection (insect proofing) of pure or blended woollen item, fur and feather lined garments, and other keratinous items from various species of insect pests, more specifically but without implying any limitation thereto.
One aspect of the present invention relates to providing an aerosol spray solution composition which can be applied easily on the woollen items, fur and feathers lined garments and other keratinous goods at industry commercial and domestic stores for at least two years and thereto, to protect such items, during their storage, use and transport.
While various embodiments and/or individual features of the present invention have been illustrated and described, it would be obvious to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the invention. As will be also be apparent to the skilled practitioner, all combinations of the embodiments and features taught in the foregoing disclosure are possible and can result in preferred executions of the present disclosure. (Disclaimer)
EXAMPLES
1) Working Example
The following example is put forth so as to provide those of ordinary skill in the art with a complete disclosure and the description of how to make and use the present invention, and are not intended to limit the scope of what the inventors regard as their invention nor are they intended to represent that the experiments below are all and only experiments performed.
First, a co-polymer solution is prepared by mixing 10 ml of acrylic acid in 30 ml of butyl acrylate. Then 15 ml of this co-polymer solution was mixed 65-70 ml of Isopropanol or mineral turpentine oil or white spirit. To this 80-85 ml solution, 3-5 ml of odours fragrances and 5-10 ml of synthetic pyrethroid insecticide were added which was then thoroughly mixed with stirrer. This insecticide spray solution was poured into a hand sprayer for spraying on woollen fabrics/garments or in ready to use aerosol container.
The preparations according to the invention are produced and made up in the conventional manner known to the person skilled in the art. Initially, therefore, insecticide, emulsifiers (copolymers) and odours/Fragrances are thoroughly mixed with solvent. This mixture is then poured into aerosol cans in liquid form. After the valve has been applied, the propellant is finally added as the last component in the case of ready to use aerosol spray.
Laboratory evaluation of this insecticidal solution was carried out as per the international standardization method (ISO 3998) by releasing 15 larvae of each species on treated wool fabric pieces of 4 cm diameter size for 14 days in a Petri dish with a perforated lid. It was observed that tile larvae of tile said insect pests did not cause any damage to tile fabric during this period.
In, another laboratory evaluation test, 10 mated female adults of each insect species were released in a 0.25 liter glass jar on a 5 cm diameter treated wool fabric pieces which substantially covered the bottom of the jar and mouth was covered with a muslin cloth held by a rubber band. Cent percent adults of the insect pests died within 24 hours of exposure and no fabric damage was observed after six weeks on treated fabrics as laid eggs of pest were killed before larval emergence. The storage stability studies showed that treated fabric/garments with tills insecticidal spray protect them from insect/pest damage up to 60 months in stores.
It is to be understood that the spray formulation of the present invention is susceptible to modifications, adaptations and changes by those skilled in the field of the present invention. Such modifications, adaptations and changes are intended to be covered within the scope of present invention which is set forth by the following claims.
2) Example
Bioefficacy Tests of Wool Care Solution
Laboratory evaluation of this wool care spray solution was carried out as per the international standardization method (ISO 3998) by releasing 15 larvae of each species on treated wool fabric pieces of 4 cm diameter size for 14 days in a Petri dish with perforated lid. It was observed that the larvae of the two common and serious insect pests did not cause any damage to the wool fabric after spraying with wool care solution up to 24 months of storage as shown below in the Table 1 & 2. A test fabric is considered satisfactorily insect proofed if all four test specimens have no holes or surface damage (cropping) visible to unaided eyes and the mean weight loss for test specimens and the weight loss for single specimens are less that 15 mg and 20 mg respectively.
TABLE 1
Effectiveness of wool care solution against two common wool pests Tinea
translucens and Anthrenus flavipes after treatment.
Anthrenus
flavipes
Tinea
translucens
Visible
Visible Damage
Mean Wt
Damage
Mean Wt
Treatment
Cropping a
Holes b
loss mg c
Status
Cropping a
Holes b
loss mg c
Status
Wool care
1
A
1.70
Proofed
1
A
2.72
Proofed
Control
Treated
3-4
D
85.06
Not
3-4
D
83.74
Not
with solvent
Proofed
proofed
Untreated
3-4
D
91.9
Not
4
D
93.92
Not
proofed
proofed
TABLE 2
Effectiveness of wool care solution against two common wool pests of Tinea
translucens and Anthrenus flavipes after treatment had aged 24 months.
Anthrenus
flavipes
Tinea
translucens
Visible
Visible Damage
Mean Wt
Damage
Mean Wt
Treatment
Cropping a
Holes b
loss mg c
Status
Cropping a
Holes b
loss mg c
Status
Wool care
1
A
1.85
Proofed
2
A
5.50
Proofed
Control
Treated
4
D
74.35
Not
4
D
100.42
Not
with solvent
Proofed
proofed
Untreated
4
D
111.44
Not
4
D
101.65
Not
proofed
proofed
a Cropping (surface damage): 1-Not detectable; 2-Very slight; 3-Moderate; and 4-Very heavy.
b Holes: A-Not detectable damage; B-Yarns partially severed; C-Few small holes and D-Several large holes.
c Mean weight loss in four test replicates by the feeding of the test insect larvae.
Another laboratory evaluation test was also carried out to determine the pests' repelling or killing efficacy of wool care spray solution by releasing 10 mated female adults of each insect species in a 0.25 liter glass jar on a 5 cm diameter wool fabric pieces sprayed with wool care solution. The bottom of the jar was substantially covered with the treated fabric piece and mouth was covered with a muslin cloth held by a rubber band to force the adult pests to come in contact with the treated fabric. It was observed that the adult pest remain away from the treated fabric. All adults of the insect pests died within 24 hours of exposure and no fabric damage was observed after six weeks on treated fabrics as laid eggs of pest were also killed before larval emergence. The storage stability studies showed that treated fabric/garments with this wool care solution spray protect them from insect/pest damage up to 60 moths in stores.
METHOD OF USE
“Wool care” aerosol spray solution can be sprayed on woollen uniforms, blankets, jerseys, rugs, carpets, upholstery items and other woollen items before their storage or during their packing for transportation either with a ready to use aerosol container having a propellant or with manually operated sprayer. For treatment with wool care aerosol spray, the woollen items can be spread on a cloth line or on the ground, and then gently spray the solution in fine aerosol drops from a distance of 15-30 cms on the exteriors of woollen items. Spray of wool care solution should be light without drenching them or run off.
ADVANTAGES OF THE PRESENT INVENTION
The previously described versions of the subject matter and its equivalent thereof have many advantages, including those which are described below
i. The present invention discloses binding of the copolymer to mineral turpentine oil/white spirit due to its high viscosity, resulting in a synergistic effect thereby maintaining the concentration of the insecticide in the solution permitting it to be used as a ready-to-use even after prolonged storage. ii. The present invention further relates to formation of a thin film of copolymer that binds the insecticide and solvent mineral turpentine oil (MTO), thereby spreading evenly over the garment surface retaining the insecticide for longer period, protecting for about 60 months of unattended storage after the spray of the insecticide. (Refer to example 2—Bioefficacy Tests of Wool Care Solution) iii. The present invention further discloses that the high viscosity of copolymer prevents deep penetration of the spray solution into the woollen fabric, thereby enabling availability of the insecticide at the very surface of the fabric, allowing no ingress to wool insects and pests. iv. The present invention also discloses that the selection of propellant is advantageous in such a way that it provides the desired pressure for uniform delivery of the wool care aerosol spray solution while spraying on the woollen items.
Although the subject matter has been described in considerable detail with reference to certain preferred embodiments thereof, other embodiments are possible. As such, the spirit and scope of the appended claims should not be limited to the description of the preferred embodiment contained therein. | The present invention relates to a wool care composition comprising pyrethroid insecticide, a copolymer and a solvent wherein the said copolymer binds with the solvent and pyrethroid insecticide. This composition can be an improved aerosol spray formulation for treating of pure or blended woollen clothing and textile, fur and feather lined garments and other keratinous items for protection or insect proofing from various types of insect pests both clothes moths and carpet beetles during their storage, transport and use. Wool care aerosol solution can be sprayed with pressurized container having either a propellant as ready-to-use aerosol or manually operated sprayers. The aerosol spray composition may also contain fragrance and solvent. The other components in the composition are at least one copolymer/emulsifier and/or dispersant. | 3 |
BACKGROUND OF THE INVENTION
Hydrophilic, i.e., water loving coatings (hereafter referred to as “WLC”) are a utilitarian chemistry that may be used for hydrophilic and hydrophobic polyurethane epoxies as a replacement of isocyanate-based coatings on, for example, medical devices. WLC chemistry is attractive since prior art isocyanates-based coating compositions and coatings that may be used present possible health concerns. Another concern, with isocyanates, is the isocyanate sensitivity to water which reacts therewith to evolve carbon dioxide. That side reaction produces a very rough coating due to micro roughness when carbon dioxide exits the coating forming small pin holes. However, once the isocyanate is end capped to form polyurethane epoxy (glycidyl carbamate) in accordance with this invention, reactions with water and off gassing are no longer a concern and health concerns are significantly reduced. The use of WLC chemistry, in medical devices, and other coating areas, is thusly very attractive particularly for medical device applications.
SUMMARY OF THE INVENTION
WLC synthesis reactions can be optimized generally by running at lower temperatures which tends to reduce side reactions. Reaction order is also a very important consideration in WLC development. In the case of oxirane polyurethane-based WLC's the methylenebisdiisocyanate (MDI) should be either a liquid or a melted solid before polyol additions and that adipic acid dihydrazide is fully reacted before adding dibutyltin dilaurate catalyst and glycidol. Adding glycidol too early may result in amine reactions with glycidol, and addition of catalyst too early may alter the chain extending network and form a less desirable coating. WLC glycidyl(oxirane functionality) termination has shown an increase in coating adhesive and cohesive strength.
In the above formulae:
“n 1 ”, relating to PEO, falls in the range of about 500 to about 45,000 or higher;
“n 2 ”, relating to polyTHF, falls in the range of about 3 to about 600 or higher;
“n 3 ”, relating to PDEGA, falls in the range of about 2 to about 60,000 or higher; and
“n 4 ” is lower alkylene, n 4 falling in the range of 1 to about 4.
Note that the n 4 alkylene group optionally couples other isocyanate moieties as is noted below.
1. Glycidol, PEO (polyethylene oxide), dimethylol propionic acid (DMPA), polytetrahydrofuran (polyTHF), and poly[di(ethylene glycol)adipate] (PDEGA hydroxyl) can react with methylenebisdiisocyanate for chain extension. 2. Adipic acid dihydrazide (AAD) reacts with isocyanate for chain extension. 3. End group is terminated with glycidol for glycidyl functionality. 4. Reaction kinetics are faster with an aromatic group next to isocyanate.
The monomers and oligomers (including the genericized polymer constituents) and synthetic route noted about was used to produce coatings/compositions of this invention.
Side reaction free reaction scheme to terminate with epoxy end groups and minimize side reactions.
The terminal oxirane polyurethane chemistry coatings of this invention primary reactions that make up the polyurethane coatings of this invention are listed below:
1. Terminal Oxirane Polyurethane Reactive Coating Compositions are an extremely lubricious durable coating that contains both hard and soft segments. This structure contains polyurethane and epoxy groups. This is a modified aqueous and solvent soluble material to increase physical crosslinks via hydrogen bonding. This structure relies on physical crosslinks for strength through hard segment domains. The hard segments contain aromatic groups, which also stack by pi-bond interactions. “Hard segments” as the term is used herein means substantially crystalline.
2. Terminal a Composition Comprising Epoxy Urethane Ester Carboxylic Acid Alkylene Oxide Reactive Coating Compositions
This example describes the preparation of an inventive water-loving coating (WLC) Epoxy urethane ester carboxylic acid alkylene oxide reactive coating compositions. A 500 mL four neck reaction kettle with condenser, nitrogen inlet and model Gemini J-KEM temperature controller, mechanical stirrer, and heating mantel was used for resin synthesis. 16.8 g of methylenebisdiisocyanate (MDI)>99.0% was charged to the reactor. The temperature was held at 40 degree C. for 40 minutes for solid softening. Next, 62.5 g of Poly[di(ethylene glycol)adipate] average M n ˜2,500, 72.5 g of Poly(tetrahydrofuran) average M n ˜2,900, and 3.35 g of 2,2-Bis(hydroxymethyl)propionic acid 98% was added, in the following order and homogenized by stirring for 5 minutes at 40.degree. C. To this homogenized mixture 150 grams of Poly(ethylene oxide) average M v 100,000, powder was added immediately following the addition of 1-Methyl-2-pyrrolidinone anhydrous, 99.5%. The solution homogenized by mixing thoroughly for 40 minutes. Four drops Dibutyltin dilaurate 95% were added drop wise and the reaction mixture was held at 40 degrees C. for one hour. After one hour 3.7 grams glycidol were added and the temperature was held overnight until reaction completion.
3. Terminal Oxirane Polyurethane Urea Chain Extender/(No Addition of Water).
Reactive Coating Compositions are an extremely lubricious durable coating that contains both hard and soft segments. The structure contains polyurethane, urea and epoxy groups. This is a modified aqueous and solvent soluble material that employs urea formation to increase physical crosslinks via hydrogen bonding. Carboxylic acid functionality in the polymer backbone and glycidol end groups add crosslinking. The epoxy end groups help with adhesion and cohesive strength. This structure relies on crosslinks much like the polyurethane epoxy but contains a chain extender based off adipic acid dihydrazide.
4. Terminal Oxirane Polyurethane Urea Chain Extender/(Water Excess).
Reactive Coating Compositions are an extremely lubricious durable coating that contains both hard and soft segments i.e., crystalline and amorphous segments. This structure contains polyurethane, urea and epoxy groups. This is a modified aqueous and solvent soluble material employs urea formation to increase physical crosslinks via hydrogen bonding. Carboxylic acid functionality in the polymer backbone and glycidol end groups add crosslinking, the reaction of isocyanate forms an unstable carbamic acid that forms an amine. The amine quickly reacts with isocyanate functionality to form a urea.
Water functionality reacts with excess MDI isocyanate to release CO 2 and form an amine. The amine functionality reacts with excess isocyanate to form additional urea linkages. The water/amine reaction is highly, physically crosslink the system and enhance its mechanical properties. The active hydrogen of the secondary amine can further react with excess isocyanate to slightly crosslink the system. The combination of urea, and polyurethane hard segments and glycidol functionalities lead to a superior crosslinking system.
Water reactions with isocyanate to form urea
5. Terminal Oxirane Polyurethane Amide/Amide Urea/(No Addition of Water).
Reactive Coating Compositions are an extremely lubricious durable coating that contains both hard and soft segments. This is structure contains polyurethane, urea, amide (amide to form urea) and epoxy groups. This is a modified aqueous and solvent soluble material employs amide formation that may undergo additional reactions to form urea. Urea and hard segments yield an increase in hydrogen bonding for physical crosslinks, carboxylic acid functionality in the polymer backbone and glycidol end groups add crosslinking. Amide functionality can continue to react with isocyanate to form urea. This crosslinking system helps increase durability of the basecoat.
Isocyanate Reaction with Amide to Form Crosslinked Urea
For example, DMPA was used to construct the polymer backbone for the introducing carboxylic acid functionality. This functionality reacts with excess MDI isocyanate around 80 C to form an amide bond. The amide reaction is to slightly cross-link the system and increase its mechanical properties. The active hydrogen of the amide functionally can further react with excess isocyanate to form urea. The combination of amide, urea, and polyurethane hard segments and glycidol functionalities lead to a superior crosslinking system.
Isocyanate Reaction with Amide to Form Crosslinked Urea
Examples 46-48 illustrate this aspect of the invention.
For example, DMPA was used to construct the polymer backbone for the introducing carboxylic acid functionality. This functionality reacts with excess MDI isocyanate around 80 C to form an amide bond. The amide reaction is to slightly crosslink the system and increase mechanical properties. The active hydrogen of amide can further react with excess isocyanate to form urea. The combination of amide, urea, and polyurethane hard segments and glycidol functionalities lead to a superior crosslinking system.
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20110015724
Kocher et al., Medical device having hydrophilic coatings
20110021657
Kocher, Hydrophilic polyurethane solutions
20110021696
Kocher et al., Hydrophilic polyurethane dispersions
Also, specifically incorporated by reference herein in its entirety is applicant's in concurrently filed patent application Ser. No. 13/834,810, entitled “Modified Hyaluronate Hydrophilic Compositions, Coatings and Methods.”
DETAILED DESCRIPTION
Examples of Composition 1
Example 1
This example describes the preparation of an inventive water loving coating (WLC) glycidyl carbamate dispersion (E-1). A 500 mL four neck reaction kettle with condenser, nitrogen inlet and model Gemini J-KEM temperature controller, mechanical stirrer, and heating mantel was used for resin synthesis. 9.375 g of 4,4′-Methylenebis(phenyl isocyanate) 98% was charged to the reactor. The temperature was held at 40° C. for 40 minutes for solid softening. Next, 4.925 g of Poly[di(ethylene glycol)adipate] average M n ˜500, 27.25 g of Poly(tetrahydrofuran) average M n ˜2,900, was added, in the following order and homogenized by stirring for 5 minutes at 40° C. To this homogenized mixture 53.57 g of Poly(ethylene oxide) average M v 100,000, powder was added immediately following the addition of 100 g of 1-Methyl-2-pyrrolidinone anhydrous, 99.5%. The solution homogenized by mixing thoroughly for 40 minutes. One drop Dibutyltin dilaurate 95% were added drop wise and the reaction mixture was held at 40° C. for one hour. After one hour 2.8 grams glycidol were added and the temperature was held overnight until reaction completion.
eg.
Example 1 (E-1)
grams
Wt
moles
4,4′-Methylenebis(phenyl isocyanate)
9.375
125
0.075
Poly [di(ethylene glycol)
4.925
250
0.0197
adipate] average M n ~500
Poly(tetrahydrofuran) average M n ~2,900
27.25
1450
0.018793
Poly (ethylene oxide) average M v 100,000
53.57
50000
0.001071
glycidol
2.8
74
0.037838
0.077402
Example 2
This example describes the preparation of an inventive water loving coating (WLC) glycidyl carbamate dispersion (E-2). A 500 mL four neck reaction kettle with condenser, nitrogen inlet and model Gemini J-KEM temperature controller, mechanical stirrer, and heating mantel was used for resin synthesis. 4.787 g of 4,4′-Methylenebis(phenyl isocyanate) 98% was charged to the reactor. The temperature was held at 40° C. for 40 minutes for solid softening. Next, 27.423 g of Poly(tetrahydrofuran) average M n ˜2,900, was added, in the following order and homogenized by stirring for 5 minutes at 40° C. To this homogenized mixture 53.57 g of Poly(ethylene oxide) average M v 100,000, powder was added immediately following the addition of 50 g of 1-Methyl-2-pyrrolidinone anhydrous, 99.5%. The solution homogenized by mixing thoroughly for 40 minutes. One drop of Dibutyltin dilaurate 95% were added drop wise and the reaction mixture was held at 40° C. for one hour. After one hour 1.8 grams glycidol were added and the temperature was held overnight until reaction completion.
eg.
Example 2 (E-2)
grams
Wt
moles
4,4′-Methylenebis(phenyl isocyanate)
4.787
125
0.038296
Poly(tetrahydrofuran) average M n ~2,900
27.423
1450
0.018912
Poly (ethylene oxide) average M v 100,000
53.57
50000
0.001071
glycidol
1.8
74
0.024324
1.044308
Example 3
This example describes the preparation of an inventive water loving coating (WLC) glycidyl carbamate dispersion (E-3). A 500 mL four neck reaction kettle with condenser, nitrogen inlet and model Gemini J-KEM temperature controller, mechanical stirrer, and heating mantel was used for resin synthesis. 18.964 g of 4,4′-Methylenebis(phenyl isocyanate) 98% was charged to the reactor. The temperature was held at 40° C. for 40 minutes for solid softening. Next, 109.99 g of Poly(tetrahydrofuran) average M n ˜2,900 was added and homogenized by stirring for 45 minutes at 40° C. To this homogenized mixture of 290 g of 1-Methyl-2-pyrrolidinone anhydrous, 99.5% was added. The solution homogenized by mixing thoroughly for 40 minutes. Four drops Dibutyltin dilaurate 95% were added drop wise and the reaction mixture was held at 40° C. for one hour. After one hour 5.5051 grams glycidol were added and the temperature was held overnight until reaction completion.
Example 3 (E-3)
grams
eg. Wt
moles
4,4′-Methylenebis(phenyl isocyanate)
19.694
125
0.157552
Poly(tetrahydrofuran) average M n ~2,900
109.99
1450
0.075855
glycidol
5.5051
74
0.074393
0.150248
Example 4
This example describes the preparation of an inventive water loving coating (WLC) glycidyl carbamate dispersion (E-4). A 500 mL four neck reaction kettle with condenser, nitrogen inlet and model Gemini J-KEM temperature controller, mechanical stirrer, and heating mantel was used for resin synthesis. 18.964 g of 4,4′-Methylenebis(phenyl isocyanate) 98% was charged to the reactor. The temperature was held at 40° C. for 40 minutes for solid softening. Next, 19.464 g of Poly[di(ethylene glycol)adipate] average M n ˜2500, 47.23 g of Poly(tetrahydrofuran) average M n ˜2,900 was added, in the following order and homogenized by stirring for 45 minutes at 40° C. To this homogenized mixture 108.28 g of Poly(ethylene oxide) average M v 100,000, powder was added immediately following the addition of 200 g of 1-Methyl-2-pyrrolidinone anhydrous, 99.5%. The solution homogenized by mixing thoroughly for 250 minutes. Four drops Dibutyltin dilaurate 95% were added drop wise and the reaction mixture was held at 40° C. for one hour. After one hour 4.048 grams glycidol were added and the temperature was held overnight until reaction completion
Example 4 (E-4)
grams
eg. Wt
moles
4,4′-Methylenebis(phenyl isocyanate)
18.964
125
0.151712
Poly [di(ethylene glycol) adipate] average
19.464
1250
0.015571
M n ~2,500
Poly(tetrahydrofuran) average M n ~2,900
47.23
1450
0.032572
Poly (ethylene oxide) average M v 100,000
108.28
50000
0.002166
glycidol
4.048
74
0.054703
0.105012
Examples for Composition 2
Example 5
This example describes the preparation of an inventive water loving coating (WLC) glycidyl carbamate dispersion (E-5). A 500 mL four neck reaction kettle with condenser, nitrogen inlet and model Gemini J-KEM temperature controller, mechanical stirrer, and heating mantel was used for resin synthesis. 6.562 g of 4,4′-Methylenebis(phenyl isocyanate) 98% was charged to the reactor. The temperature was held at 40° C. for 40 minutes for solid softening. Next, 14.4 g of Poly[di(ethylene glycol)adipate] average M n ˜2,500, 16.28 g of Poly(tetrahydrofuran) average M n ˜2,900, and 0.6903 g of 2,2-Bis(hydroxymethyl) propionic acid 98% was added, in the following order and homogenized by stirring for 5 minutes at 40° C. To this homogenized mixture 50.0 of Poly(ethylene oxide) average M v 100,000, powder was added immediately following the addition of 100 g of 1-Methyl-2-pyrrolidinone anhydrous, 99.5%. The solution homogenized by mixing thoroughly for 40 minutes. Four drops Dibutyltin dilaurate 95% were added drop wise and the reaction mixture was held at 40° C. for one hour. After one hour 0.3129 grams glycidol were added then 0.0741 grams of water were added after 45 minutes and the temperature was held overnight until reaction completion.
Example 5 (E-5)
grams
eg. Wt
moles
4,4′-Methylenebis(phenyl isocyanate)
6.562
125
0.052496
Poly [di(ethylene glycol) adipate] average
14.4
1250
0.01152
M n ~2500
Poly(tetrahydrofuran) average M n ~2,900
16.28
1450
0.011228
2,2-Bis(hydroxymethyl)propionic acid
0.693
67.5
0.010267
Poly (ethylene oxide) average M v 100,000
50
50000
0.001
glycidol
0.3129
74
0.004228
0.038243
Example 6
This example describes the preparation of an inventive water loving coating (WLC) glycidyl carbamate dispersion (E-6). A 500 mL four neck reaction kettle with condenser, nitrogen inlet and model Gemini J-KEM temperature controller, mechanical stirrer, and heating mantel was used for resin synthesis. 10.33 g of 4,4′-Methylenebis(phenyl isocyanate) 98% was charged to the reactor. The temperature was held at 40° C. for 40 minutes for solid softening. Next, 25.82 g of Poly[di(ethylene glycol)adipate] average M n ˜2,500, 29.95 g of Poly(tetrahydrofuran) average M n ˜2,900, and 1.38 g of 2,2-Bis(hydroxymethyl) propionic acid 98% was added, in the following order and homogenized by stirring for 5 minutes at 40° C. To this homogenized mixture 30.98 g of Poly(ethylene oxide) average M v 100,000, powder was added immediately following the addition of 1-Methyl-2-pyrrolidinone anhydrous, 99.5%. The solution homogenized by mixing thoroughly for 40 minutes. Four drops Dibutyltin dilaurate 95% were added drop wise and the reaction mixture was held at 40° C. for one hour. After one hour 1.52 grams glycidol were added and the temperature was held overnight until reaction completion.
Example 6 (E-6)
grams
eg. Wt
moles
4,4′-Methylenebis(phenyl isocyanate)
10.33
125
0.08264
Poly [di(ethylene glycol) adipate] average
25.82
1250
0.020656
M n ~2500
Poly(tetrahydrofuran) average M n ~2,900
29.95
1450
0.020655
2,2-Bis(hydroxymethyl)propionic acid
1.38
67.5
0.020444
Poly (ethylene oxide) average M v 100,000
30.98
50000
0.00062
glycidol
1.52
74
0.020541
0.082916
Example 7
This example describes the preparation of an inventive water loving coating (WLC) glycidyl carbamate dispersion (E-7). A 500 mL four neck reaction kettle with condenser, nitrogen inlet and model Gemini J-KEM temperature controller, mechanical stirrer, and heating mantel was used for resin synthesis. 16.8 g of 1,6-Diisocyanatohexane>99.0% was charged to the reactor. The temperature was held at 40° C. for 40 minutes for solid softening. Next, 62.5 g of Poly[di(ethylene glycol)adipate] average M n ˜2,500, 72.5 g of Poly(tetrahydrofuran) average M n ˜2,900, and 3.35 g of 2,2-Bis(hydroxymethyl)propionic acid 98% was added, in the following order and homogenized by stirring for 5 minutes at 40° C. To this homogenized mixture 1-Methyl-2-pyrrolidinone anhydrous, 99.5% was added. The solution homogenized by mixing thoroughly for 40 minutes. Four drops Dibutyltin dilaurate 95% were added drop wise and the reaction mixture was held at 40° C. for one hour. After one hour 3.7 grams glycidol were added and the temperature was held overnight until reaction completion.
Example 7 (E-7)
grams
eg. Wt
moles
1,6-Diisocyanatohexane
16.8
84
0.2
Poly [di(ethylene glycol) adipate] average
62.5
1250
0.05
M n ~2,500
Poly(tetrahydrofuran) average M n ~2,900
72.5
1450
0.05
2,2-Bis(hydroxymethyl)propionic acid
3.35
67.5
0.04963
Poly (ethylene oxide) average M v 100,000
72.5
50000
0.00145
glycidol
3.7
74
0.05
0.20108
Examples for Composition 3
Example 8
This example describes the preparation of an inventive water loving coating (WLC) glycidyl carbamate dispersion (E-8). A 500 mL four neck reaction kettle with condenser, nitrogen inlet and model Gemini J-KEM temperature controller, mechanical stirrer, and heating mantel was used for resin synthesis. 20.14 g of 4,4′-Methylenebis(cyclohexyl isocyanate), mixture of isomers 90% was charged to the reactor. The temperature was held at 40 degree C. for 40 minutes for solid softening. Next, 62.16 g of Poly(tetrahydrofuran) average M n ˜2,900, and 3.061 g of 2,2-Bis(hydroxymethyl)propionic acid 98% was added, in the following order and homogenized by stirring for 5 minutes at 40° C. To this homogenized mixture 43.34 g of Poly(ethylene oxide) average M v 100,000, powder was added immediately following the addition of 300 g of 1-Methyl-2-pyrrolidinone anhydrous, 99.5%. The solution homogenized by mixing thoroughly for 40 minutes. Six drops Dibutyltin dilaurate 95% were added drop wise and the reaction mixture was held at 40° C. for one hour. After one hour 3.2192 g of Adipic acid dihydrazide≧98% were added and mixed for two hours. To this homogenized mixture 7.5 grams glycidol were added and the temperature was held overnight until reaction completion.
eg.
Example 8 (E-8)
Grams
Wt
moles
of 4,4′-
20.14
131
0.153740458
Methylenebis(cyclohexyl
isocyanate)
Poly(tetrahydrofuran)
43.34
1450
0.029889655
average M n ~2,900
2,2-Bis(hydroxy-
3.061
67.5
0.045348148
methyl)propionic
acid
Poly (ethylene oxide)
62.16
50000
0.0012432
average M v 100,000
Adipic acid dihydrazide
3.2192
87.1
0.036959816
glycidol
7.5
74
0.101351351
0.214792171
Example 9
This example describes the preparation of an inventive water loving coating (WLC) glycidyl carbamate dispersion (E-9). A 500 mL four neck reaction kettle with condenser, nitrogen inlet and model Gemini J-KEM temperature controller, mechanical stirrer, and heating mantel was used for resin synthesis. 18.964 g of 4,4′-Methylenebis(phenyl isocyanate) 98% was charged to the reactor. The temperature was held at 40° C. for 40 minutes for solid softening. Next, 134.85 g of Poly(tetrahydrofuran) average M n ˜2,900, was added and homogenized by stirring for 40 minutes at 40° C. To this homogenized mixture 216.75 g of Poly(ethylene oxide) average M v 100,000, powder was added immediately following the addition of 290 g of 1-Methyl-2-pyrrolidinone anhydrous, 99.5%. The solution homogenized by mixing thoroughly for 40 minutes. Four drops Dibutyltin dilaurate 95% were added drop wise and the reaction mixture was held at 40° C. for one hour. After one hour 1.956 g of Adipic acid dihydrazide≧98% were added and mixed for two hours. To this homogenized mixture 0.33 grams glycidol were added and the temperature was held overnight until reaction completion.
eg.
Example 9 (E-9)
grams
Wt
moles
4,4′-Methylenebis(phenyl isocyanate)
134.85
125
1.0788
Poly (ethylene oxide) average M v 100,000
216.75
50000
0.004335
Adipic acid dihydrazide
1.956
87.1
0.0225028
glycidol
0.33
74
0.004459
Poly(tetrahydrofuran) average M n ~2,900
134.85
1450
0.093
0.1242968
Example 10
This example describes the preparation of an inventive water loving coating (WLC) glycidyl carbamate dispersion (E-10). A 500 mL four neck reaction kettle with condenser, nitrogen inlet and model Gemini J-KEM temperature controller, mechanical stirrer, and heating mantel was used for resin synthesis. 18.964 g of 4,4′-Methylenebis(phenyl isocyanate) 98% was charged to the reactor. The temperature was held at 40° C. for 40 minutes for solid softening. Next, 33.379 g of Poly[di(ethylene glycol)adipate] average M n ˜2,500, 47.255 g of Poly(tetrahydrofuran) average M n ˜2,900, and 2.000 g of 2,2-Bis(hydroxymethyl)propionic acid 98% was added, in the following order and homogenized by stirring for 5 minutes at 40° C. To this homogenized mixture 216.748 g of Poly(ethylene oxide) average M v 100,000, powder was added immediately following the addition of 1-Methyl-2-pyrrolidinone anhydrous, 99.5%. The solution homogenized by mixing thoroughly for 40 minutes. Four drops Dibutyltin dilaurate 95% were added drop wise and the reaction mixture was held at 40° C. for one hour. After one hour 1.956 g of Adipic acid dihydrazide≧98% were added and mixed for two hours. To this homogenized mixture 0.33 grams glycidol were added and the temperature was held overnight until reaction completion
Example 10 (E-10)
grams
eg. Wt
moles
4,4′-Methylenebis(phenyl isocyanate)
18.964
125
0.151712
Poly [di(ethylene glycol) adipate]
33.379
1250
0.0267032
average M n 2500
Poly(tetrahydrofuran) average
47.255
1450
0.03258
M n ~2,900,
2,2-Bis(hydroxymethyl)propionic acid
2.000 g
67.5
0.029629
Poly (ethylene oxide) average
216.748
50000
0.04335
M v 100,000
Adipic acid dihydrazide
1.956
87.1
0.02245569
glycidol
0.33
74
0.00445
0.15916789
Example 11
This example describes the preparation of an inventive water loving coating (WLC) glycidyl carbamate dispersion (E-11). A 500 mL four neck reaction kettle with condenser, nitrogen inlet and model Gemini J-KEM temperature controller, mechanical stirrer, and heating mantel was used for resin synthesis. 18.972 g of 4,4′-Methylenebis(phenyl isocyanate) 98% was charged to the reactor. The temperature was held at 40° C. for 40 minutes for solid softening. Next, 33.29 g of Poly[di(ethylene glycol)adipate] average M n ˜2,500, 47.92 g of Poly(tetrahydro-furan) average M n ˜2,900, and 1.994 g of 2,2-Bis(hydroxymethyl)propionic acid 98% was added, in the following order and homogenized by stirring for 5 minutes at 40° C. To this homogenized mixture 43.349 g of Poly(ethylene oxide) average M v 100,000, powder was added immediately following the addition of 290 g of 1-Methyl-2-pyrrolidinone anhydrous, 99.5%. The solution homogenized by mixing thoroughly for 40 minutes. Four drops Dibutyltin dilaurate 95% were added drop wise and the reaction mixture was held at 40° C. for one hour. After one hour 1.958 g of Adipic acid dihydrazide≧98% were added and mixed for two hours. To this homogenized mixture 2.426 grams glycidol were added and the temperature was held overnight until reaction completion.
Example 11 (E-11)
grams
eg. Wt
moles
4,4′-Methylenebis(phenyl isocyanate)
18.792
125
0.150336
Poly [di(ethylene glycol) adipate]
33.29
1250
0.026632
average M n ~2,500
Poly(tetrahydrofuran) average
47.92
1450
0.03304828
M n ~2,900
2,2-Bis(hydroxymethyl)propionic acid
1.994
67.5
0.02954074
Poly (ethylene oxide) average
43.349
50000
0.00086698
M v 100,000
Adipic acid dihydrazide
1.958
87.1
0.02247991
glycidol
2.426
74
0.03278378
0.14535169
Examples for Composition 4
Example 12
This example describes the preparation of an inventive water loving coating (WLC) glycidyl carbamate dispersion (E-12). A 500 mL four neck reaction kettle with condenser, nitrogen inlet and model Gemini J-KEM temperature controller, mechanical stirrer, and heating mantel was used for resin synthesis. 18.964 g of 4,4′-Methylenebis(phenyl isocyanate) 98% was charged to the reactor. The temperature was held at 40° C. for 40 minutes for solid softening. Next, 40.456 g of Poly[di(ethylene glycol)adipate] average M n ˜2,500, 45.911 g of Poly(tetrahydrofuran) average M n ˜2,900, and 1.939 g of 2,2-Bis(hydroxymethyl)propionic acid 98% was added, in the following order and homogenized by stirring for 5 minutes at 40° C. To this homogenized mixture 210.0 g of Poly(ethylene oxide) average M v 100,000, powder was added immediately following the addition of 290 g of 1-Methyl-2-pyrrolidinone anhydrous, 99.5%. The solution homogenized by mixing thoroughly for 250 minutes. Four drops Dibutyltin dilaurate 95% were added drop wise and the reaction mixture was held at 40° C. for one hour. After one hour 1.37 g of Adipic acid dihydrazide≧98% were added and mixed for two hours. To this homogenized mixture 1.436 grams glycidol were added and the temperature was held overnight until reaction completion. The final addition involved 0.3533 grams water to form a urea.
eg.
Example 12 (E-12)
grams
Wt
moles
4,4′-Methylenebis(phenyl isocyanate)
18.964
125
0.151712
Poly [di(ethylene glycol) adipate]
40.456
1250
0.0323648
average M n ~2,500
Poly(tetrahydrofuran) average
45.911
1450
0.031662759
M n ~2,900
2,2-Bis(hydroxymethyl)propionic
1.939
67.5
0.028725926
acid
Poly (ethylene oxide) average
210
50000
0.0042
M v 100,000
Adipic acid dihydrazide
1.37
87.1
0.015729047
glycidol
1.436
74
0.019405405
0.132087937
WATER
0.3533
18
0.01963
Example 13
This example describes the preparation of an inventive water loving coating (WLC) glycidyl carbamate dispersion (E-13). A 500 mL four neck reaction kettle with condenser, nitrogen inlet and model Gemini J-KEM temperature controller, mechanical stirrer, and heating mantel was used for resin synthesis. 18.964 g of 4,4′-Methylenebis(phenyl isocyanate) 98% was charged to the reactor. The temperature was held at 40° C. for 40 minutes for solid softening. Next, 33.38 g of Poly[di(ethylene glycol)adipate] average M n ˜2500, 47.23 g of Poly(tetrahydrofuran) average M n ˜2,900 was added, and 1.99 g of 2,2-Bis(hydroxymethyl)propionic acid 98% was added, in the following order and homogenized by stirring for 45 minutes at 40° C. To this homogenized mixture 53.57 g of Poly(ethylene oxide) average M v 100,000, powder was added immediately following the addition of 200 g of 1-Methyl-2-pyrrolidinone anhydrous, 99.5%. The solution homogenized by mixing thoroughly for 250 minutes. Four drops Dibutyltin dilaurate 95% were added drop wise and the reaction mixture was held at 40° C. for one hour. After one hour 1.354 g of Adipic acid dihydrazide≧98% were added and mixed for two hours. To this homogenized mixture 2.427 grams glycidol were added and the temperature was held overnight until reaction completion. The final addition involved 0.2409 grams water to form a urea.
eg.
Example 13 (E-13)
grams
Wt
moles
4,4′-Methylenebis(phenyl isocyanate)
18.964
125
0.151712
Poly [di(ethylene glycol) adipate]
33.38
1250
0.026704
average M n ~2,500
Poly(tetrahydrofuran) average
47.25
1450
0.032586207
M n ~2,900
2,2-Bis(hydroxymethyl)propionic acid
1.9999
67.5
0.029628148
Poly (ethylene oxide) average
53.57
50000
0.0010714
M v 100,000
Adipic acid dihydrazide
1.354
87.1
0.01554535
glycidol
2.427
74
0.032797297
0.138332403
WATER
0.2409
18
0.013382
Examples for Composition 5
Example 14
This example describes the preparation of an inventive water-loving coating (WLC) glycidyl carbamate dispersion (E-14). A 500 mL four neck reaction kettle with condenser, nitrogen inlet and model Gemini J-KEM temperature controller, mechanical stirrer, and heating mantel was used for resin synthesis. 18.964 g of 4,4′-Methylenebis(phenyl isocyanate) 98% was charged to the reactor. The temperature was held at 40° C. for 40 minutes for solid softening. Next, 40.457 g of Poly[di(ethylene glycol)adipate] average M n ˜2,500, 45.911 g of Poly(tetrahydrofuran) average M n ˜2,900, and 1.939 g of 2,2-Bis(hydroxymethyl)propionic acid 98% was added, in the following order and homogenized by stirring for 5 minutes at 40° C. To this homogenized mixture 210.71 g of Poly(ethylene oxide) average M v 100,000, powder was added immediately following the addition of 290 g of 1-Methyl-2-pyrrolidinone anhydrous, 99.5%. The solution homogenized by mixing thoroughly for 40 minutes. Four drops Dibutyltin dilaurate 95% were added drop wise and the reaction mixture was held at 40° C. for one hour. After one hour 1.3789 g of Adipic acid dihydrazide≧98% were added and mixed for two hours. To this homogenized mixture 1.436 grams glycidol were added and the temperature was held overnight until reaction completion.
Example 14 (E-14) POLYURETHANE
eg.
UREA W/EXCESS NCO
grams
Wt
moles
4,4′-Methylenebis(phenyl isocyanate)
18.964
125
0.151712
Poly [di(ethylene glycol) adipate]
40.457
1250
0.0323656
average M n ~2,500
Poly(tetrahydrofuran) average
45.911
1450
0.031662759
M n ~2,900
2,2-Bis(hydroxymethyl)propionic acid
1.939
67.5
0.028725926
98%
Adipic acid dihydrazide
1.3789
87.1
0.015831228
glycidol
1.436
74
0.019405405
0.127990918
Examples for the Cross-Linking Reaction
Example 15
This example describes the preparation of an inventive water loving coating (WLC) glycidyl carbamate dispersion (E-15). A 500 mL four neck reaction kettle with condenser, nitrogen inlet and model Gemini J-KEM temperature controller, mechanical stirrer, and heating mantel was used for resin synthesis. 10.33 g of 4,4′-Methylenebis(phenyl isocyanate) 98% was charged to the reactor. The temperature was held at 40° C. for 40 minutes for solid softening. Next, 25.82 g of Poly[di(ethylene glycol)adipate] average M n ˜2,500, 29.95 g of Poly(tetrahydrofuran) average M n ˜2,900, and 1.38 g of 2,2-Bis(hydroxymethyl) propionic acid 98% was added, in the following order and homogenized by stirring for 5 minutes at 40° C. To this homogenized mixture 30.98 g of Poly(ethylene oxide) average M v 100,000, powder was added immediately following the addition of 1-Methyl-2-pyrrolidinone anhydrous, 99.5%. The solution homogenized by mixing thoroughly for 40 minutes. Four drops Dibutyltin dilaurate 95% were added drop wise and the reaction mixture was held at 60° C. for one hour for homopolymerization. After one hour 1.52 grams glycidol were added and the temperature was held for 72 hours.
Example 15 (E-15)
grams
eg. Wt
moles
4,4′-Methylenebis(phenyl isocyanate)
8.264
125
.066112
Poly [di(ethylene glycol) adipate]
20.656
1250
.0165248
average M n ~2500
Poly(tetrahydrofuran) average
23.96
1450
.016524
M n ~2,900
2,2-Bis(hydroxymethyl)propionic acid
1.104
67.5
.0163552
Poly (ethylene oxide) average M v 100,000
24.78
50000
.000496
glycidol
1.21
74
.016432
.0663328
Example 16
This example describes the preparation of an inventive water-loving coating (WLC) Epoxy urethane alkylene oxide reactive coating compositions. A 500 mL four neck reaction kettle with condenser, nitrogen inlet and model Gemini J-KEM temperature controller, mechanical stirrer, and heating mantel was used for resin synthesis. 18.964 g of 4,4′-Methylenebis(phenyl isocyanate) 98% was charged to the reactor. The temperature was held at 40 degree C. for 40 minutes for solid softening. Next, 109.99 g of Poly(tetrahydrofuran) average M n ˜2,900 was added and homogenized by stirring for 45 minutes at 40.degree. C. To this homogenized mixture of 290 g of 1-Methyl-2-pyrrolidinone anhydrous, 99.5% was added. The solution homogenized by mixing thoroughly for 40 minutes. Four drops Dibutyltin dilaurate 95% were added drop wise and the reaction mixture was held at 40 degrees C. for one hour. After one hour 5.5051 grams glycidol were added and the temperature was held overnight until reaction completion.
Example 17
This example describes the preparation of an inventive water-loving coating (WLC) Epoxy urethane ester carboxylic acid alkylene oxide reactive coating compositions. A 500 mL four neck reaction kettle with condenser, nitrogen inlet and model Gemini J-KEM temperature controller, mechanical stirrer, and heating mantel was used for resin synthesis. 16.8 g of 1,6-Diisocyanatohexane>99.0% was charged to the reactor. The temperature was held at 40° C. for 40 minutes for solid softening. Next, 62.5 g of Poly[di(ethylene glycol)adipate] average M n ˜2,500, 72.5 g of Poly(tetrahydrofuran) average M n ˜2,900, and 3.35 g of 2,2-Bis(hydroxymethyl)propionic acid 98% was added, in the following order and homogenized by stirring for 5 minutes at 40° C. To this homogenized mixture 150 grams of Poly(ethylene oxide) average M v 100,000, powder was added immediately following the addition of 1-Methyl-2-pyrrolidinone anhydrous, 99.5%. The solution homogenized by mixing thoroughly for 40 minutes. Four drops Dibutyltin dilaurate 95% were added drop wise and the reaction mixture was held at ° C. for one hour. After one hour 3.7 grams glycidol were added and the temperature was held overnight until reaction completion.
Example 18
This example describes the preparation of an inventive water-loving coating (WLC) Epoxy urethane urea carboxylic acid alkylene oxide reactive coating compositions. A 500 mL four neck reaction kettle with condenser, nitrogen inlet and model Gemini J-KEM temperature controller, mechanical stirrer, and heating mantel was used for resin synthesis. 18.964 g of 4,4′-Methylenebis(phenyl isocyanate) 98% was charged to the reactor. The temperature was held at 40° C. for 40 minutes for solid softening. Next, 33.379 g of Poly[di(ethylene glycol)adipate] average M n ˜2,500, 47.255 g of Poly(tetrahydrofuran) average M n ˜2,900, and 2.000 g of 2,2-Bis(hydroxymethyl)propionic acid 98% was added, in the following order and homogenized by stirring for 5 minutes at 40° C. To this homogenized mixture 216.748 g of Poly(ethylene oxide) average 100,000, powder was added immediately following the addition of 1-Methyl-2-pyrrolidinone anhydrous, 99.5%. The solution homogenized by mixing thoroughly for 40 minutes. Four drops Dibutyltin dilaurate 95% were added drop wise and the reaction mixture was held at 40 degrees C. for one hour. After one hour 1.956 g of Adipic acid dihydrazide≧98% were added and mixed for two hours. To this homogenized mixture 0.33 grams glycidol were added and the temperature was held overnight until reaction completion.
Example 19
This example describes the preparation of an inventive water loving coating (WLC) Epoxy urethane urea carboxylic acid alkylene oxide reactive coating compositions. A 500 mL four neck reaction kettle with condenser, nitrogen inlet and model Gemini J-KEM temperature controller, mechanical stirrer, and heating mantel was used for resin synthesis. 18.964 g of 4,4′-Methylenebis(phenyl isocyanate) 98% was charged to the reactor. The temperature was held at 40° C. for 40 minutes for solid softening. Next, 40.456 g of Poly[di(ethylene glycol)adipate] average M n ˜2,500, 45.911 g of Poly(tetrahydrofuran) average M n ˜2,900, and 1.939 g of 2,2-Bis(hydroxymethyl)propionic acid 98% was added, in the following order and homogenized by stirring for 5 minutes at 40° C. To this homogenized mixture 210.0 g of Poly(ethylene oxide) average M v 100,000, powder was added immediately following the addition of 290 g of 1-Methyl-2-pyrrolidinone anhydrous, 99.5%. The solution homogenized by mixing thoroughly for 250 minutes. Four drops Dibutyltin dilaurate 95% were added drop wise and the reaction mixture was held at 40 degrees C. for one hour. After one hour 1.37 g of Adipic acid dihydrazide≧98% were added and mixed for two hours. To this homogenized mixture 1.436 grams glycidol were added and the temperature was held overnight until reaction completion. The final addition involved 0.3533 grams water to form a urea.
SUMMARY OF WLC CONNECTIVITY
Basecoat terminal epoxy groups react with top coat epoxy groups through ARM amine functionality which increase adhesive strength. Basecoat chemistry contains Easaqua XM-502, which is added during the base coat mixing step. This aqueous isocyanate contains mpeg for use in water based applications. When this material is added to basecoat the isocyanate reacts with the carboxylic acid and open epoxide hydroxyl groups for basecoat cohesive strength. Easaqua XM-502 also reacts with top coat ARM and open hydroxyl groups for adhesive strength.
Once crosslinked, with Easaqua XM-502, then the base coat becomes a hydrogel. The hydrogel crosslinks take in water and swell via soft segments (Terethane, PEO and PEDGA) to render the coating water loving with high lubricity. Crosslink chemistry allows water to become retained within the walls of the soft segment without going into solution. This chemical and physical process leads to an extremely durable and lubricious coating.
WLC Oxirane Connections
A resin sample of an aqueous polyurethane polymer was submitted to NSL Analytical Laboratories on Nov. 2, 2009 for characterization of the polymer. Various Mass Spectrometry techniques were utilized in this characterization, including Electro-Spray Ionization (ESI), Matrix Assisted Laser Desorption Ionization (MALDI) and Chemical Ionization (CI). The following are abbreviations are used to describe findings:
GA glycidol alcohol DEG diethylene glycol DMPA dimethylolpropionic acid DEGA diethyleneglycol adipate MDI methylene-diiscocyanate PEG polyethylene glycol PDEGA polydiethyleneglycol adipate
Abbreviations Used to Describe Findings
The sample was analyzed by 1H NMR with the sample dissolved in TCE. This was able to provide the monomer ratios listed below.
MDI 1 mol Adipic 2.875 mol DEG 3.075 mol PTMEG (poly THF) 11 mol of THF PEG (i.e. PEO) 24 moles of EO Glycidolcarbonate 0.5 mol DMPA 0.27 mol
Monomer Ratios Determined by Proton NMR
Coating Example Composition 1
Materials as synthesized above were then applied to substrates noted below in the following fashion:
Coating Polyurethane Tungsten Loaded Jacket
a. An aqueous and or solvent dispersion basecoat was prepared from 8.8 g of composition 1 AND 0.2 Easaqua XM-502 were then added to the formulation and stirred at 900 rpm for 15 minutes. b. Basecoat (of this invention) was applied to the polyurethane jacketed wire, by dip coating, at a set speed for a desired film thickness c. The basecoat was then cured either at ambient or thermally until no longer-tacky d. An aqueous dispersion topcoat was prepared with crosslinker in the following order: (1) 0.005 grams Poly(ethylene oxide), 4-arm, amine terminated average M n ˜10,000 was added to a one ounce bottle then (2) 0.02 '956 patent. To this crosslinker 11.576 grams of modified hyaluronan top coat formulated resin was added and crosslinker was stirred at 1800 rpm for 5 minutes e. Topcoat of the concurrently filed application noted above was then applied at a set speed for desired film thickness f. The coating was then cured at ambient or thermally until fully cured g. The final cured product resulted in a highly lubricious coating
Coating Metal Wire Substrate with Adhesion Promoter
Preparation of Adhesion Promoter
i. 100 mL ETOH (ETOH anhydrous) provided by Sigma ii. Add 5.0 gram water iii. Stir 10 minutes iv. Add 3.84 grams 3-aminopropyltriethoxysilane (Provided by Gelest) v. Mix 5 minutes a. Coating wire with adhesion promoter vi. Pour adhesion promoter into 100 mL burette (use shaker to mix) vii. Place wire in graduated cylinder solution for 10 minutes viii. Take wire out of solution and place in 125 C oven for 10 minutes
Polyurethane tungsten loaded jacket
b. An aqueous and or solvent dispersion basecoat was prepared from 8.8 g of composition 1 AND 0.015 Easaqua XM-502 were then added to the formulation and stirred at 900 rpm for 15 minutes. c. The wire from step a-viii was taken out of the 125 C oven for coating d. Basecoat was applied to the metal wire substrate with adhesion promoter, by dip coating, at a set speed for a desired film thickness e. The basecoat was then cured either at ambient or thermally until no longer-tacky f. An aqueous dispersion intermediate layer was prepared with Easaqua XM-502 (0.015) crosslinker, '956 patent and adipic acid dihydrazide (0.02). To this crosslinker 8.8 grams composition 1 plus water were formulated and stirred at 1800 RPM for 5 minutes. The intermediate layer contained 0.01 TPP catalyst. g. Intermediate layer was then applied at a set speed for desired film thickness h. The intermediate layer was then cured either at ambient or thermally until no longer-tacky i. An aqueous dispersion topcoat was prepared with crosslinker in the following order: (1) 0.01 grams adipic acid dihydrazide was added to a one ounce bottle then (2) 0.01 grams PZ-28 To this crosslinker 11.576 grams composition 2 was added to the crosslinker, which was stirred at 1800 rpm for 5 minutes j. Topcoat was then applied at a set speed for desired film thickness k. The coating was then cured at ambient or thermally until fully cured l. The final cured product resulted in a highly lubricious coating
Coating Example Composition 3
Materials were then applied to substrates noted below in the following fashion:
Coating Polyurethane Tungsten Loaded Jacket
h. An aqueous and or solvent dispersion basecoat was prepared from 8.8 g of composition 3 AND 0.2 Polyaziridine PZ-28 were then added to the formulation and stirred at 900 rpm for 15 minutes. i. Basecoat was applied to the polyurethane jacketed wire, by dip coating, at a set speed for a desired film thickness j. The basecoat was then cured either at ambient or thermally until no longer-tacky k. An aqueous dispersion topcoat was prepared with crosslinker in the following order: (1) 0.002 grams Poly(ethylene oxide), 4-arm, amine terminated average M n ˜10,000 was added to a one ounce bottle then (2) 0.0252 grams '956 patent. To this crosslinker 11.576 grams of modified hyaluronan top coat formulated resin was added and crosslinker was stirred at 1800 rpm for 5 minutes l. Topcoat was then applied at a set speed for desired film thickness m. The coating was then cured at ambient or thermally until fully cured n. The final cured product resulted in a highly lubricious coating
Coating Metal Wire Substrate with Adhesion Promoter
Preparation of Adhesion Promoter
i. 100 mL ETOH (ETOH anhydrous) provided by Sigma ii. Add 5.0 gram water iii. Stir 10 minutes 1. Add 3.84 grams 3-aminoethyltriethoxysilane (Provided by Gelest) iv. v. Mix 5 minutes m. Coating wire with adhesion promoter vi. Pour adhesion promoter into 100 mL burette (use shaker to mix) vii. Place wire in graduated cylinder solution for 10 minutes viii. Take wire out of solution and place in 125 C oven for 10 minutes
Polyurethane tungsten loaded jacket
n. An aqueous and or solvent dispersion basecoat was prepared from 8.8 g of composition 3 AND 0.2 Polyaziridine PZ-28 were then added to the formulation and stirred at 900 rpm for 15 minutes. o. The wire from step viii was taken out of the 125 C oven for coating p. Basecoat was applied to the metal wire substrate with adhesion promoter, by dip coating, at a set speed for a desired film thickness q. The basecoat was then cured either at ambient or thermally until no longer-tacky r. An aqueous dispersion topcoat was prepared with crosslinker in the following order: (1) 0.002 grams Poly(ethylene oxide), 4-arm, amine terminated average M n ˜10,000 was added to a one ounce bottle then (2) 0.0252 grams '956 patent. To this crosslinker 11.576 grams of modified hyaluronan top coat formulated resin was added and crosslinker was stirred at 1800 rpm for 5 minutes s. Topcoat was then applied at a set speed for desired film thickness t. The coating was then cured at ambient or thermally until fully cured u. The final cured product resulted in a highly lubricious coating
Coating Example Composition 5
Materials were then applied to substrates noted below in the following fashion:
Coating Polyurethane Tungsten Loaded Jacket
o. An aqueous and or solvent dispersion basecoat was prepared from 8.8 g of composition 5 and stirred at 900 rpm for 15 minutes. p. Basecoat was applied to the polyurethane jacketed wire, by dip coating, at a set speed for a desired film thickness q. The basecoat was then cured either at ambient or thermally until no longer-tacky r. An aqueous dispersion topcoat was prepared with crosslinker in the following order: (1) 0.0005 grams Poly(ethylene oxide), 4-arm, amine terminated average M n ˜10,000 was added to a one ounce bottle then (2) 0.0000271 grams '956 patent. To this crosslinker 11.576 grams of modified hyaluronan top coat formulated resin was added and crosslinker was stirred at 1800 rpm for 5 minutes s. Topcoat was then applied at a set speed for desired film thickness t. The coating was then cured at ambient or thermally until fully cured u. The final cured product resulted in a highly lubricious coating
Coating Metal Wire Substrate with Adhesion Promoter
Preparation of Adhesion Promoter
i. 100 mL ETOH (ETOH anhydrous) provided by Sigma ii. Add 5.0 gram water iii. Stir 10 minutes iv. Add 3.84 grams 3-aminopropyltriethoxysilane (Provided by Gelest) v. Mix 5 minutes v. Coating wire with adhesion promoter vi. Pour adhesion promoter into 100 mL burette (use shaker to mix) vii. Place wire in graduated cylinder solution for 10 minutes viii. Take wire out of solution and place in 125 C oven for 10 minutes
Polyurethane tungsten loaded jacket
v. An aqueous and or solvent dispersion basecoat was prepared from 8.8 g of composition 5 and stirred at 900 rpm for 15 minutes. w. Basecoat was applied to the polyurethane jacketed wire, by dip coating, at a set speed for a desired film thickness x. The basecoat was then cured either at ambient or thermally until no longer-tacky y. An aqueous dispersion topcoat was prepared with crosslinker in the following order: (1) 0.0005 grams Poly(ethylene oxide), 4-arm, amine terminated average M n ˜10,000 was added to a one ounce bottle then (2) 0.0000271 grams '956 patent. To this crosslinker 11.576 grams of modified hyaluronan top coat formulated resin was added and crosslinker was stirred at 1800 rpm for 5 minutes z. Topcoat was then applied at a set speed for desired film thickness aa. The coating was then cured at ambient or thermally until fully cured w. The final cured product resulted in a highly lubricious coating
Coating Example Composition 7
Materials were then applied to substrates noted below in the following fashion:
Coating Polyurethane Tungsten Loaded Jacket
bb. An aqueous and or solvent dispersion basecoat was prepared from 8.8 g of composition 7 AND 0.2 Easaqua XM-502 were then added to the formulation and stirred at 900 rpm for 15 minutes Basecoat was applied to the polyurethane jacketed wire, by dip coating, at a set speed for a desired film thickness cc. The basecoat was then cured either at ambient or thermally until no longer-tacky dd. An aqueous dispersion topcoat was prepared with crosslinker in the following order: (1) 0.02 grams Poly(ethylene oxide), 4-arm, amine terminated average M n ˜10,000 was added to a one ounce bottle then (2) 0.015 grams '956 patent. To this crosslinker 11.576 grams of modified hyaluronan top coat formulated resin was added and crosslinker was stirred at 1800 rpm for 5 minutes ee. Topcoat was then applied at a set speed for desired film thickness ff. The coating was then cured at ambient or thermally until fully cured gg. The final cured product resulted in a highly lubricious coating
Coating Metal Wire Substrate with Adhesion Promoter
Preparation of Adhesion Promoter
i. 100 mL ETOH (ETOH anhydrous) provided by Sigma ii. Add 5.0 gram water iii. Stir 10 minutes iv. Add 3.84 grams 3-aminopropyltriethoxysilane v. Mix 5 minutes x. Coating wire with adhesion promoter vi. Pour adhesion promoter into 100 mL burette (use shaker to mix) vii. Place wire in graduated cylinder solution for 10 minutes viii. Take wire out of solution and place in 125 C oven for 10 minutes
Polyurethane tungsten loaded jacket
hh. An aqueous and or solvent dispersion basecoat was prepared from 8.8 g of composition 7 AND 0.2 Easaqua XM-502 were then added to the formulation and stirred at 900 rpm for 15 minutes Basecoat was applied to the polyurethane jacketed wire, by dip coating, at a set speed for a desired film thickness ii. The basecoat was then cured either at ambient or thermally until no longer-tacky jj. An aqueous dispersion topcoat was prepared with crosslinker in the following order: (1) 0.005 grams Poly(ethylene oxide), 4-arm, amine terminated average M n ˜10,000 was added to a one ounce bottle then (2) 0.01 grams '956 patent. To this crosslinker 11.576 grams of modified hyaluronan top coat formulated resin was added and crosslinker was stirred at 1800 rpm for 5 minutes kk. Topcoat was then applied at a set speed for desired film thickness ll. The coating was then cured at ambient or thermally until fully cured y. The final cured product resulted in a highly lubricious and durable coating
Coating Example Composition 9
Materials were then applied to substrates noted below in the following fashion:
Coating Polyurethane Tungsten Loaded Jacket
mm. An aqueous and or solvent dispersion basecoat was prepared from 8.8 g of composition 9 AND 0.02 Easaqua XM-502 were then added to the formulation and stirred at 900 rpm for 15 minutes Basecoat was applied to the polyurethane jacketed wire, by dip coating, at a set speed for a desired film thickness nn. The basecoat was then cured either at ambient or thermally until no longer-tacky oo. An aqueous dispersion topcoat was prepared with crosslinker in the following order: (1) 0.002 grams Poly(ethylene oxide), 4-arm, amine terminated average M n ˜10,000 was added to a one ounce bottle then (2) 0.002 grams '956 patent. To this crosslinker 11.576 grams of modified hyaluronan top coat formulated resin was added and crosslinker was stirred at 1800 rpm for 5 minutes pp. Topcoat was then applied at a set speed for desired film thickness qq. The coating was then cured at ambient or thermally until fully cured rr. The final cured product resulted in a highly lubricious coating
Coating Metal Wire Substrate with Adhesion Promoter
Preparation of Adhesion Promoter
i. 100 mL ETOH (ETOH anhydrous) provided by Sigma ii. Add 5.0 gram water iii. Stir 10 minutes 2. Add 3.84 grams 3-trimethoxysilylpropyl-diethylenetriamine (Provided by Gelest) iv. v. Mix 5 minutes z. Coating wire with adhesion promoter vi. Pour adhesion promoter into 100 mL burette (use shaker to mix) vii. Place wire in graduated cylinder solution for 10 minutes viii. Take wire out of solution and place in 125 C oven for 10 minutes
Polyurethane tungsten loaded jacket
ss. An aqueous and or solvent dispersion basecoat was prepared from 8.8 g of composition 9 AND 0.02 Easaqua XM-502 were then added to the formulation and stirred at 900 rpm for 15 minutes Basecoat was applied to the polyurethane jacketed wire, by dip coating, at a set speed for a desired film thickness tt. The basecoat was then cured either at ambient or thermally until no longer-tacky uu. An aqueous dispersion topcoat was prepared with crosslinker in the following order: (1) 0.002 grams Poly(ethylene oxide), 4-arm, amine terminated average M n ˜10,000 was added to a one ounce bottle then (2) 0.002 grams '956 patent. To this crosslinker 11.576 grams of modified hyaluronan top coat formulated resin was added and crosslinker was stirred at 1800 rpm for 5 minutes vv. Topcoat was then applied at a set speed for desired film thickness ww. The coating was then cured at ambient or thermally until fully cured xx. The final cured product resulted in a highly lubricious and durable coating 1. A composition comprising epoxy urethane alkylene oxide reactive coating compositions of the structure of formula (I).
2. The composition of paragraph 1, wherein the epoxy urethane alkylene oxide reactive coating compositions are
(a) Polytrimethylene ether glycol, with n having a number average molecular weight in the range of about 1,000 to about 4,000,000 where n=11 to about 46. (b) Optional Polyethylene oxide, with m having a number average molecular weight in the range of about 18,000 to about 2,000,000 where n=375 to about 41,667 (c) Optional Poly[di(ethylene glycol)adipate, with o having a number average molecular weight in the range of about 400 to about 10,000.00 where n=2 to about 50 (d) Glycidyl moieties are represented by the addition of glycidol
3. A composition comprising epoxy urethane ester carboxylic acid alkylene oxide reactive coating compositions of the following structure (II):
4. The composition of paragraph 3, wherein the epoxy urethane ester carboxylic acid alkylene oxide reactive coating compositions are
(a) Poly[di(ethylene glycol) adipate having a number average molecular weight in the range of about 400 to about 10,000.00 where n=2 to about 50 (b) Optional Polytrimethylene ether glycol having a number average molecular weight in the range of about 1,000 to about 4,000,000 where n=11 to about 46. (c) Optional Polyethylene oxide having a number average molecular weight in the range of about 18,000 to about 2,000,000 where n=375 to about 41,667 (d) Acid moieties are represented by the addition of dimethylol propionic acid (e) Glycidyl moieties are represented by the addition of glycidol (f) Excess isocyanate can react with dimethylol propionic acid to form an amide resulting in a urea
5. A composition comprising epoxy urethane urea carboxylic acid alkylene oxide reactive coating compositions of the following structure (III):
6. The composition of paragraph 5, wherein the epoxy urethane urea carboxylic acid alkylene oxide reactive coating compositions are:
(a) Poly[di(ethylene glycol) adipate having a number average molecular weight in the range of about 400 to about 10,000.00 where n=2 to about 50 (b) Optional Polytrimethylene ether glycol having a number average molecular weight in the range of about 1,000 to about 4,000,000 where n=11 to about 46. (c) Optional Polyethylene oxide having a number average molecular weight in the range of about 18,000 to about 2,000,000 where n=375 to about 41,667 (d) Acid moieties are represented by the addition of dimethylol propionic acid (e) Glycidyl moieties are represented by the addition of glycidol (f) Urea moieties are represented by the addition of adipic acid dihydrazide (g) Excess isocyanate can react with dimethylol propionic acid to form an amide resulting in a urea
7. A composition comprising epoxy urethane urea (based off water addition) carboxylic acid alkylene oxide reactive coating compositions of the following structure (IV):
8. The composition of paragraph 7, wherein the epoxy urethane urea carboxylic acid alkylene oxide reactive coating compositions are:
(a) Poly[di(ethylene glycol) adipate having a number average molecular weight in the range of about 400 to about 10,000.00 where n=2 to about 50 (b) Optional Polytrimethylene ether glycol having a number average molecular weight in the range of about 1,000 to about 4,000,000 where n=11 to about 46. (c) Optional Polyethylene oxide having a number average molecular weight in the range of about 18,000 to about 2,000,000 where n=375 to about 41,667 (d) Acid moieties are represented by the addition of dimethylol propionic acid (e) Glycidyl moieties are represented by the addition of glycidol (f) Urea moieties are represented by the addition of reduced isocyanate system then adding water
9. A composition comprising epoxy urethane urea (based off excess iscoyanate) carboxylic acid alkylene oxide reactive coating compositions of the following structure (V):
10. The composition of paragraph 9, wherein the epoxy urethane urea carboxylic acid alkylene oxide reactive coating compositions are:
(a) Poly[di(ethylene glycol) adipate having a number average molecular weight in the range of about 400 to about 10,000.00 where n=2 to about 50 (b) Optional Polytrimethylene ether glycol having a number average molecular weight in the range of about 1,000 to about 4,000,000 where n=11 to about 46. (c) Optional Polyethylene oxide having a number average molecular weight in the range of about 18,000 to about 2,000,000 where n=375 to about 41,667 (d) Acid moieties are represented by the addition of dimethylol propionic acid (e) Glycidyl moieties are represented by the addition of glycidol (f) Urea moieties are represented by the addition of excess isocyanate, in the system, to adipic acid dihydrazide
11. An aqueous soluble or solvent soluble or mixture comprising claims paragraphs 1-10.
12. A composition of paragraph 11, where an aqueous soluble solvent is water and solvent soluble solvents are aprotic.
13. A composition of paragraph 12, where the aprotic solvents are NMP, DMSO or DMF.
14. A composition of paragraph 11, where the solvent can be a polar non-reactive solvent
15. A composition of paragraph 14, where the solvent can be PMA, Acetone or MEK.
16. A composition of paragraphs 1-10 where a chain extender is added.
17. A composition of paragraphs 1-10 where the curing agent is a self-crosslinking reaction via homopolymerization or polyetherification.
18. A composition of paragraph 17, where kinetics of the reaction are improved with temperature
19. A composition comprising a mixture compounds with structures (I), (II), (III), (IV) and (V)
20. A coating composition of paragraphs 1-10 further comprising a curing agent
21. A coating composition of paragraphs 3-10, wherein the curing agent is an aziridine curing agent
22. A composition of paragraph 21, where basecoat carboxylic acid groups can react with polyaziridine (PZ-28 or PZ-33):
a) Polyaziridine PZ-28 reaction with basecoat (paragraph 22):
b) Polyaziridine PZ-28 or PZ-33, added to basecoat (paragraphs 3-10), reacts with carboxylic acid in modified Hyaluronic Acid topcoat:
c) Polyaziridine PZ-28 or PZ-33 (paragraph 22), connecting basecoat to modified Hyaluronic Acid topcoat:
23. A composition of paragraphs 1-10, where epoxy groups can react with an amine cross-linking agents (Figure below).
24. The coating composition of paragraph 23, wherein the amine curing agent is Poly(ethylene oxide), 4-arm, amine terminated
25. Basecoat epoxy groups can react with Poly(ethylene oxide), 4-arm, amine terminated found in topcoat.
a. The '956 patent epoxy groups can react with Poly(ethylene oxide), 4-arm, amine terminated and Poly(ethylene oxide), 4-arm, amine terminated can react with basecoat to increase adhesive strength.
26. A composition of paragraphs 1-10, where open hydroxyl groups from epoxy group ring opening can react with isocyanate cross-linking agents (Figure below).
27. The coating composition of paragraph 26, wherein the isocyanate curing agent is Easaqua XM-502
a) Easaqua XM-502 added to the basecoat reacts with basecoat carboxylic acid:
b. Easaqua XM-502 added to the basecoat reacts with Poly(ethylene oxide), 4-arm, amine added as a crosslinker to the top-coat:
c. Easaqua XM-502 added to the basecoat reacts with open hydroxyls when the base-coat epoxy ring opens:
d. Easaqua XM-502 added to the basecoat reacts with open hydroxyls when the '956 patent ring opens:
e. Easaqua XM-502 reacts with hydroxyl groups found in Hyaluronic acid:
f. Easaqua XM-502 reacts with carboxylic groups found in Hyaluronic acid:
28. A composition of paragraphs 1-10, where epoxy groups can be end-capped with mono-functional amines:
29. A composition of paragraphs 3-10 where adding dimethylpropionic acid (DMPA) can lead to cross-linking sites and also help with water dispersion by forming water reducible epoxy polyurethanes.
30. A composition of paragraph 29, where acid groups of DMPA can be neutralized with an amine then dispersed in water.
31. A composition of paragraphs 1-10, where linear polyurethane epoxy polymers are elastomeric and can elongate.
32. A composition of paragraphs 1-10, where hydration forms a hydrogel via physical cross-links; or, slight cross-linking can cause a swelling (hydrogel formation) or plasticization effect resulting in a lubricious polyurethane end capped glycidyl based polymers.
33. Epoxy termination of paragraphs 1-10 may crosslink by amines, amides, carboxylic acids and hydroxyl functionality.
34. A coating composition of paragraph 33, where open hydroxyl functionality, from epoxy ring group opening, can undergo hydroxyl reactions.
35. A composition of paragraphs 1-10, are affected by diisocyanate type.
36. The coating composition of paragraphs 1-10, wherein the diisocyanate is selected from 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, 4,4′-diphenylmethane diisocyanate, 4,4′-dicyclohexylmethane diisocyanate, 3,3′-dimethyl-4,4′-biphenyl diisocyanate, 4,4′methylene diphenyl diisocyanate, polymeric MDI, naphthalene diisocyanate, 4,4′-diisocynatodicyclohexylmethane, 1,4-benzene diisocyanate, trans-cyclohexane-1,4-diisocyanate, 1,5-naphthalene diisocyanate, 1,6-hexamethylene diisocyanate, 4,6-xylene diisocyanate, isophorone diisocyanate, with combinations and isomers thereof.
37. A composition of paragraphs 1-10, are reacted with polyol cross-linkers.
38. A composition of paragraphs 1-10, are reacted with amine cross-linkers.
39. A composition of paragraphs 5-10, where a diol or amine chain extender is added.
40. The coating composition of paragraph 20, wherein the diol chain extender is selected from hydroquinone-bis-(hydroxymethyl)ether, ethylene glycol, 1,2-propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol, diethylene glycol, 2-methyl-1,3-propanediol, 3-methyl-1,5-pentanediol, 2,2-dimethyl-1,3-propanediol, 2,2,4-trimethyl-1,5-pentanediol, 2-methyl-2-ethyl-1,3-propanediol, 1,4-bis(hydroxyethoxy)benzene, bis(hydroxyethylene)terephthalate, hydroquinone bis(2-hydroxyethyl)ether, and combinations and isomers thereof.
41. The coating composition of paragraph 20, wherein the amine chain extender is selected from 2,4 and 2,6 diethtltoluene diamine, methylene-bis-orthochloroaniline, unilink (UOP LLC), 4,4′-methylene-bis(3-chloro-2,6-diethylaniline), 1,2-ethylenediamine, 1,6-hexanediamine, 1,2-propanediamine, 4,4′-methylene-bis(3-chloroaniline), dimethylthiotoluenediamine, 4,4′diaminodiphenylmethane, 1,3-diaminobenzene, 1,4-diaminobenzene, 3,3′dimethoxy-4,4′-diaminobiphenyl, 3,3′-dichloro-4,4′-diamino biphenyl, and combinations and isomers thereof.
42. Paragraph 36 isocyanate selection, and isomers, affect physical crosslinks of the final epoxy terminated polyurethane polymer.
43. A coating composition of paragraph 42, where 4-4′MDI terminated epoxy polyurethanes provides excellent hard block domains due to linearity and aromatic groups.
44. A coating composition of paragraph 42, where isocyanate isomers of 2-4-TDI and 2,6-TDI react differently and impart different resin properties of the terminated polyurethane epoxy.
45. A coating composition of paragraph 36, where isocyanate crosslinkers can react with open hydroxyl functional groups (epoxy ring opening) to improve durability.
46. A composition of paragraphs 1-10, where pre-polymers can be made first then terminated with glycidol.
47. A composition of paragraphs 1-10, where a one shot synthesis can be used with all monomers, including glycidol, are added all at once.
48. A composition of paragraph 47, where monomers can be added to the reaction non-sequentially at any time during the reaction. | The present invention relates to hydrophilic, i.e., water loving coatings (hereafter referred to as “WLC”). Polyurethane epoxy alkylene oxide coatings usable as coatings on for example, medical devices are a preferred WLC. | 2 |
BACKGROUND OF THE INVENTION
Computer networking uses various data communications techniques to transmit information from one computer to another over a network. A typical network includes a series of interconnected data communications devices that can each exchange data from one device to another, enabling the exchange of information. In a typical computer networking application, source and destination computer hosts are personal computers, workstations, clients and servers or the like which each include a modem or other transmitter that is used to establish a connection to the network and transmit the data from the computer.
Quite often, a portion of the data communications path upon which data travels between a source and destination computer host is comprised of a dial-up connection. Dial-up connections, as their name implies, do not always exist. Rather, they are created on an as-needed basis to create a data link between two data communications devices. Until the establishment of communications between the source and destination host exists, a dial-up connection may not be in existence for one or more segments of the network path used to transfer data.
For example, suppose a computer on the Internet begins to transmit packets of data that are destined for a remote host located in an isolated area. Further assume there is not permanent or dedicated connection to and from the remote host. On route to the destination host, the data packets are routed to a router on the Internet that is called an edge system. An edge system or edge router is typically a Network Access Server (NAS) that includes a number of IP network interfaces permanently coupled to the Internet, as well as a number of dial-in/dial-out interfaces allowing call connections to be placed (and received) over a circuit switched network such as a Public Switched Telephone System (PSTN). The edge NAS detects that the arriving data packets are destined for the remotely located host (via routing information in the packets) and initiates a dial-up connection to the remote host. Once the dial-up connection is established via modem communications between the remote host and the NAS, the data packets can be successfully transmitted (and received) to and from the remote host. When the communications session is ended by either one of the source or destination (i.e. remote) hosts, the dial-up connection between the NAS and the remote host is disconnected.
The above example is called “dial on demand routing” because the dial-up connections are made on an as-needed basis. In the above example and in this specification, the packet-based IP network (e.g., the Internet) which includes the edge NAS system is called the local network. The host to which the dial up connection is made may be a single host or may be an edge router or NAS on an entirely separate network and is called the remote host.
In an IP network such as the Internet, the routes which data packets take while traveling through the network from one device to another between a source and destination host are determined by various Internet Protocol (IP) routing protocols. IP routes which point from a local edge router system (e.g., the NAS above) to a remote host may be installed (i.e., configured within the devices on the network) by configuration or by dynamic routing mechanisms. Essentially, a route means that all IP data traffic originating on the local network is routed through the local edge system designated in the route. When the first packet of data arrives on this route, the edge system establishes the dial-up connection. The dial-up connection is made to a switched circuit network which can include circuit switched (e.g., PSTN, ISDN, T1 Signaling) and switch virtual circuit (i.e. X.25, ATM, L2TP) networks.
Conditions in the local network (i.e., the Internet) may occur which require more than one dial-up connection to be established to the remote host. For example, each dial-up connection requires the use of one port in the NAS. If there are many existing dial-up connections in use to various remote systems, there may be no ports left to establish a new dial-up connection that is required for packets arriving for a remote host not already connected. Alternatively, a situation may arise where a single existing dial-up connection to a remote host does not provide enough bandwidth for all of the data packets that must be sent and received by the remote host. If there are no more dial-out ports available on the NAS, the NAS is said to be congested or over-subscribed.
To avoid congestion there are two prior art mechanisms to allow multiple local systems (i.e., two or more NAS's) to connect to a single remote system. The two mechanisms are called “Equal Cost Routing” and “Unequal Cost Routing”.
In Equal Cost Routing, multiple routes to the same remote host are established and are given an equal weighting in the routing protocol. A weight given to a route is used to determine which edge system receives a given packet for forwarding to the remote host. As packets are transferred through the network, they may be forwarded to one of many edge systems, each of which indicates the same weight, thus lessening the chance that any one edge system becomes overcrowded.
In Unequal Cost Routing, a priority is established between edge systems that can connect with a remote system. A lesser priority edge system is used to establish a dial-up connection if a higher priority edge system is not advertising its route(s) to the remote system. Route advertising is a mechanism by which a router can indicate to other routers the capability to provide a path to a specified system. In unequal cost routing, if a router is malfunctioning due to congestion or over subscription, the congested edge system can cease advertising it route. Packets for the remote system will then be routed to a lesser priority system which can then establish the dial-up connection to the remote system.
Another aspect of data communications related to dial-on-demand routing is called “bandwidth-on-demand.” Bandwidth-on-demand in the prior art is known to work well for dial-in connections from remote systems to edge systems, but dial-out is only known to work well when all calls originate from the same edge server. Bandwidth-on-demand allows a remote system to detect that more bandwidth is required for one or more dial-in data communication sessions that are currently active. As such, bandwidth-on-demand provides the remote systems the ability to create an additional dial-in connection(s) to the edge system to satisfy the additional band-width requirements. The additional dial-in connection(s) off-load the bandwidth requirements from the existing heavily loaded connection(s). Bandwidth on demand is also referred to as a multi-link Point-To-Point (PPP) connection.
SUMMARY OF THE INVENTION
Prior art data communication systems that use dial-on-demand and bandwidth-on-demand schemes suffer from a variety of problems. Dial-on-demand systems that use equal cost routing can have situations where packets sent between the same source and destination host take different routes through the network and use different edge systems to connect with the same remote system. This results in an inefficient use of network resources since multiple dial-up connections must be established to the same remote host. Moreover, since each packet may take a different route to the remote host, specialized queuing techniques for such things as quality of service are difficult or impossible to implement. In large networks, equal cost routing is difficult to implement since many calls to the same remote host may result.
Unequal cost dial-on-demand routing systems also suffer in a number of ways. If the remote system is heavily accessed, the high priority edge router is likely to become oversubscribed. Unequal cost routing does not redirect packets if the primary edge router is congested or oversubscribed. Rather, the packets sent to the high priority router are discarded. Once the route through the primary router is no longer advertised, only subsequently transmitted packets from the source will be picked up by the lower priority router. Thus, until the new connection is established, packet arrivals will continue to be sent to the high priority host and connection data will be lost.
There are no known bandwidth-on-demand systems that can provide dial-out features from more than one edge system, such as a Network Access Server. The present invention overcomes the aforementioned problems related to dial-on-demand and bandwidth-on-demand systems. The present invention provides.
An embodiment of the invention is an edge network access server providing scalable dial-on-demand routing of a network packet. The edge network access server containing a system processor, a system memory having a router for routing the network packet to alternate edge network access servers and a list of alternate edge network access servers, and a system bus connecting the system processor, and the system memory. Additionally, the edge network access server may contain dial communication ports for creating dial connections to a remote host system and local communication ports for interfacing to a local host system.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing and other objects, features and advantages of the invention will be apparent from the following more particular description of preferred embodiments of the invention, as illustrated in the accompanying drawings in which like reference characters refer to the same parts throughout the different views. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention.
FIG. 1 illustrates a networking environment configured according to the present invention.
FIG. 2 illustrates the components that comprise an edge system such as an access server as configured according to the invention.
FIG. 3 a and FIG. 3 b illustrate a schematic data flow diagram showing the transfer of data through a data communications device configured to provide scaling dial-on-demand functionality according to this invention.
FIG. 4 illustrates a schematic data flow diagram showing the transfer of data through a data communications device configured to provide scaling bandwidth-on-demand functionality according to this invention.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 illustrates an example of a data communications networking environment 100 configured according to the invention. The network environment 100 includes a local network 110 linking hosts 111 through 116 and a remote network 101 which interconnects remote hosts 102 and 103 .
The remote network 101 may be any type of connectionless or packet-based network such as the Internet or a local area packet network maintained within a company, for example.
The local network 110 may be any type of connectionless or packet-based network such as the Internet or a local area packet network maintained within a company, for example. The local hosts 111 through 113 may be routers, bridges, switches, servers, hubs or simply standalone computer systems which can route data over links 122 , 123 and 124 within local network 110 . In this embodiment, local hosts 114 through 116 are called edge hosts and are preferably network access servers (NAS's) provided together in a stack group 117 . The local hosts 114 through 116 in the stack group 117 serve as edge hosts on local network 110 and offer dial-on demand and bandwidth-on-demand features as defined by this invention. Edge hosts 114 through 116 each include interfaces (not specifically shown in this figure) to local hosts such as 111 through 113 on local network 110 , as well as dial interfaces (not specifically shown) for maintaining connections with remote hosts such as 102 and 103 on remote network 101 .
The remote hosts 102 and 103 each include a dial-in and/or dial-out connection mechanism (not shown in this figure) allowing dial-up connections to be maintained between other remote hosts and edge hosts 114 through 116 .
According to this invention, each edge host 114 through 116 is equipped with the ability to provide scalable dial-on-demand routing. As an example, suppose local host 113 initiates the transmission of packets onto data link 124 . Further suppose each packet has a destination address of remote host 102 . The packets are routed from local host 113 over data link 124 to local host 112 and then over data link 123 to local host 111 and then over data link 122 to edge host 114 . The path the packets take within local network 110 is determined according to the routing tables maintained in each local host 111 through 116 .
According to the invention, when the packets arrive at edge host 114 , the edge host 114 determines that they are destined for remote host 102 , which must be reached using a dial-out connection. Edge host 114 , however, may be congested with heavy amounts of data traffic, or may be oversubscribed in which case there are no dial-out ports available for further connections. In the system of the invention, edge host 114 can communicate and negotiate with another edge host, such as edge host 115 , to establish a connection 121 to remote host 102 . Through a signaling process which will be described in more detail, the edge host 115 is able to establish connection 121 with remote host 102 and is able to indicate the existence of connection 121 back to edge host 114 . During the establishment of connection 121 , packets arriving at edge host 114 for remote host 102 are buffered to prevent packet loss. Once the connection 121 is established, all packets for remote host 102 are re-routed to edge host 115 for further transmission to remote host 102 .
It is to be understood that the initial connection 120 to remote host 102 may never have been created, or alternatively, connection 120 may exist at the onset of the congestion or over subscription conditions at edge host 114 . That is, connection 120 may exist and be used to transfer some packets to remote host 102 . Then, should edge host 114 become congested and require greater bandwidth, the process explained above can be used to in effect provide bandwidth-on-demand for dial-out purposes. That is, connection 121 may be established to off-load some of the high bandwidth conditions that can occur on edge host 114 . The processing details of the system of this invention will now be explained in greater detail.
FIG. 2 illustrates a block diagram of the architecture of the edge system 114 as configured according to this invention. Edge system 114 includes a bus 160 which couples a processor 158 , a memory 159 , a plurality of dial ports 150 - 153 and a plurality of local ports 154 - 157 . Local ports 154 - 157 can accept connections to and from local systems within local network 110 such as local systems 111 - 113 . Dial ports 150 - 153 can place dial out connections and can accept dial in connections to and from remote systems such as remote systems 102 and 103 on remote network 101 . The edge system processor 158 controls the overall operation of edge system 114 which generally serves as a router to transfer data between the various dial ports 150 - 153 and local ports 154 - 157 . A dial-on-demand routing program 164 resides in memory 159 and executes in conjunction with processor 158 to perform the routing functions according to this invention. Also maintained within memory 159 is an alternate list 162 whose purpose will be discussed in more detail later. As discussed briefly, edge system 114 as configured according to this invention can provide the capability of scaling dial-on-demand connections to alternate dial ports 150 - 153 within this edge system 114 or may negotiate with other edge systems to handle dial-on-demand routing calls as will be discussed in detail next.
FIGS. 3 a and 3 b show the processing steps performed by the system of this invention according to a preferred embodiment. Steps 300 through 311 in FIGS. 3 a and 3 b are discussed in relation to primary and secondary edge systems. In this context, a primary edge system is a system in which a route to a remote system on a remote network is installed. That is, in a primary edge system, a route to a remote system such as remote system 102 is currently being advertised to other local systems 111 - 113 within local network 110 . This, however, does not necessarily mean that a connection has yet been established to the remote system for which the primary edge system advertises a route. A secondary edge system in the context of FIGS. 3 a and 3 b is an edge system which does not yet advertise a route for a particular remote system of interest. For example, if edge system 114 is advertising the ability to create a dial-on-demand connection to remote system 102 , this would be done by advertising a route to remote system 102 thus making edge system 114 a primary edge system. Edge systems 115 and 1116 would not typically be advertising the route to remote system 102 at the same time as edge system 114 and thus would be secondary edge systems. Thus for the context of FIG. 3 , the primary edge system will be by way of example, edge system 114 while the secondary edge systems will be edge systems 115 and 116 . Also for this example, the remote host or system will be remote host 102 within remote network 101 .
According to this invention, in step 300 , a packet of data that is destined for remote host 102 arrives from within local network 110 at the primary edge system 114 . In step 301 , the primary edge system 114 obtains information concerning the remote host 102 for which the packet is destined. Primary edge system 114 communicates with the authentication/authorization/accounting (AAA) server 109 to obtain the information concerning remote host 102 in step 301 . The information obtained from the AAA server 109 includes such things as a phone number to dial in order to connect with remote system 102 as well as the name of the host of remote system 102 . Other information obtained from AAA server 109 may include quality of service and maximum data rate levels for a connection to be established with remote system 102 .
Once connection information is obtained concerning remote host 102 , in step 302 the primary edge system performs a resource check and an authentication check (using information obtained from the AAA server 109 ) to determine if it is possible to dial out to remote host 102 . Step 302 allows the primary edge system to check for various conditions such as congestion within the primary edge system 114 and over subscription in which case there are no dial ports 150 - 153 available. If a dial out is possible, step 311 is performed which causes a dial-out connection 120 ( FIG. 1 ) to be established with remote host 102 .
If, in step 302 , a dial-out connection cannot be made from the primary edge system 114 due to congestion, over subscription, or another problem, step 303 is performed. In step 303 , the primary edge system 114 sends a stack group bidding protocol (SGBP) broadcast message to all edge systems (i.e., edge systems 115 , 116 ) maintained in the alternate list 162 (FIG. 1 ). The SGBP broadcast message is essentially a request sent out to other edge systems from the primary edge system in order to determine and select an alternate edge system which can make a dial-out connection to remote host 102 . In a preferred embodiment, the alternate list 162 which is maintained in the edge system memory 159 contains a list of other edge systems 115 , 116 within the same stack group of edge systems 117 . That is, if a primary edge system such as edge system 114 is congested or oversubscribed, the SGBP broadcast message is sent to other edge systems within the same stack group 117 . Alternatively, an SGBP-like broadcast message could be sent to edge systems located in entirely different locations or in other stack groups.
In step 304 , each secondary edge system 115 , 116 that receives the SGBP broadcast message and that has resources available to perform a dial-out connection to remote host 102 responds affirmatively to the SGBP broadcast message sent from the primary edge system 114 .
In step 305 a , the primary edge system receives the responses from each edge system 115 , 116 which affirmatively responded to the SGBP broadcast message and determines if any secondary edge systems are available. In Step 305 b , if it is determined that no secondary edge systems are available then an indication is made that no dial-out is possible. In Step 305 c the primary edge server selects one of the responding secondary edge servers using a weighted selection criteria, the primary edge server then requests a resource reservation from the selected secondary edge server. In Step 305 d the primary edge server determines if the selected secondary edge severs accepted the reservation, if it did, processing continues at Step 306 , if the selected secondary edge sever rejected the reservation, processing resumes at Step 305 a , where the next available secondary edge server with the highest weight is selected. As such, in steps 305 a - 305 d the primary edge system selects one of the responding secondary edge systems 115 , 116 which has the highest weight associated with it to be the dial-out edge system. That is, each edge system 115 , 116 which responds to the SGBP broadcast message may have an associated weight. The weight of an edge system may be determined by various factors. For instance, if edge system 115 is capable of providing very high data rates, the weight of edge system 115 may be relatively high. Conversely, if edge system 116 can only provide modest data rates, its response to the primary edge system in step 304 may indicate a relatively modest weight.
Once the primary edge system 114 has selected a secondary edge system (e.g., edge system 115 ) as a secondary edge system, the primary edge system 114 , in step 306 , passes the name of the remote host 102 to the selected secondary edge system 115 . Preferably, the name of the remote system 102 is passed from the primary edge system 1114 to the secondary edge system 115 via an SGBP dial-out request message. An SGBP dial-out request message is an additional message added to the SGBP protocol according to this invention. The SGBP dial-out request message essentially is a request sent from the primary edge system 114 to the secondary edge system 115 which instructs the secondary edge system 115 to set up and establish a dial-out connection with the remote host 102 as specified in the SGBP dial-out request message.
In step 307 , the secondary edge system 115 can use the AAA server 109 to obtain the dial-out information for the remote system 102 for which the connection is to be established. In an alternative embodiment, it may be the case that the SGBP dial-out request message transmitted in step 306 can include the dial-out information for the remote system 102 . Accordingly, step 307 may be an optional step included in an alternative embodiment.
In step 308 , the secondary edge system 115 places a call to (i.e., dials the phone number of) the remote system 102 . In step 309 , the secondary edge system 115 establishes a connection with the remote system 102 and once established, creates a route in a routing table maintained by the secondary edge system 115 . Also in step 309 , the secondary edge system 115 redistributes the new route over the local network 110 so that other local systems such as 111 , 112 and 113 are aware of the connection established from secondary edge system 115 to the remote system 102 . Finally, in step 310 , the primary edge system 114 detects the appearance of the new route distributed in step 309 and releases all buffered packets which are addressed for the remote system 102 . In this manner, a primary edge system is able to select a secondary edge system which has the capability to establish a dial-out connection with a remote system at times when the primary edge system is not able to do so. Once the connection is established between the secondary edge system and the remote system, the primary edge system is able to release any buffered packets to prevent any packet loss within the data communication session.
According to another aspect of the invention, the system of the invention allows dial-out bandwidth-on-demand to be accomplished. As an example, if edge system 114 is currently using an established dial-out connection 120 to communicate with remote system 102 but requires more bandwidth, the invention allows edge system 114 to create additional connections with remote system 102 . The additional connections may be created completely within or upon edge system 114 , or alternatively, may be created with the use of additional edge systems such as 115 or 116 . Bandwidth-on-demand using dial out from local network 110 to remote network 101 allows remote system 102 to not be concerned with having to maintain a prescribed amount of bandwidth. Rather, bandwidth-on-demand as provided by the invention allows bandwidth from local network 110 to remote network 101 to be scaled as needed based upon data transmission requirements of local hosts within local network 110 .
In an alternative embodiment for secondary edge system selection, the secondary edge systems 115 , 116 each receive the SGBP broadcast message and reserve resources in order to perform the dial out should they be selected as the secondary edge system of choice. When secondary edge systems detect the appearance of the new route to the remote system 102 they can then release the reserved dial-out resources.
FIG. 4 illustrates the processing steps provided by an edge system configured according to the invention to provide scaling bandwidth-on-demand capabilities. In step 400 , a communications link 120 ( FIG. 1 ) to remote system 102 is established within primary edge system 114 . Also, primary edge system 114 is currently advertising a primary route through itself to remote system 102 on local network 110 . That is, after step 400 , connection 120 exists and edge system 114 is advertising the route via connection 120 to remote system 102 .
In step 401 , as data packets are being transmitted over connection 120 to remote system 102 , the primary edge system 114 detects a bandwidth-on-demand problem. That is, the primary edge system 114 detects that the bandwidth capabilities of the connection 120 are being used beyond a maximum prescribed density. As such, according to this invention, the primary edge system 114 can establish one or more secondary connections with remote system 102 .
To do so, the primary edge system, in step 402 , determines if it can handle an additional dial-out connection to remote system 102 . The processing in step 402 may, for instance determine if there are any dial-out ports 150 - 153 available to create a dial-out connection to remote system 102 . If there are dial-out ports 150 - 153 available and if the edge system 114 is not congested, step 409 is processed to perform the creation of an additional dial-out connection to remote system 102 .
However, if the primary edge system 114 determines in step 402 that a dial-out connection to remote system 102 cannot be created within the primary edge system 114 itself, step 403 is processed. In step 403 , the processing steps 303 through 309 of FIG. 3 are performed which establish a secondary connection and a secondary route to remote system 102 through one of the alternate edge systems 115 , 116 . That is, the processing of step 403 is identical to that described above with respect to steps 303 through 309 of FIG. 3 . Accordingly, after step 403 , a secondary connection 121 is established with remote system 102 from the secondary edge system 115 . Note that step 310 from FIG. 3 is not executed in step 403 of FIG. 4 .
In step 404 , the primary edge system 114 detects the existence of the secondary route to the remote system 102 as broadcast by the secondary edge system 115 . In step 405 , the primary edge system 114 sets a weight of the primary route (e.g., connection 120 to remote system 102 ) to be the same as the weight of the secondary route (e.g., connection 121 to remote system 102 ). That is, in step 405 , once the primary edge system 114 has detected the presence or existence of the secondary connection 121 , the primary edge system 114 sets the weight of the pre-existing connection 120 to have the same weight as the secondary connection 121 . In this manner, step 405 allows each connection 120 and 121 to the remote system 102 to have the same weight within local network 110 .
After step 405 , either one of steps 406 or 407 may be performed, where each is an alternative embodiment of the invention. In step 406 , the primary and secondary edge systems 114 and 115 which are each maintaining respective connections 120 and 121 to remote system 102 each use a load balancing technique to advertise the routes for connections 120 and 121 to local systems within local network 110 . That is, in step 406 , a load balancing technique is used by any local hosts, such as local systems 111 - 113 , in order to determine which of the two possible routes through either edge system 114 or 115 that may be used to transmit data to remote system 102 .
A preferred embodiment of the invention proceeds according to step 407 in which the primary and secondary edge systems 114 and 115 use a technique known as multi-link PPP and layer 2 forwarding mechanisms to appear to all local systems 111 - 113 on local network 110 as a multi-link PPP bundle. That is, since edge system 114 and 115 both maintain a connection to remote system 102 , according to step 407 , the edge systems 114 and 115 use multi-link PPP methods and layer 2 forwarding mechanisms which are known in the art, to appear as a multi-link PPP bundle to local network 110 .
Typically, multi-link PPP bundles are only used in the prior art systems to allow edge systems to offer multi-link connection services for dial-in services only. That is, if a remote system such as remote system 102 needed an additional dial-in connection to local network 110 , remote system 102 could use prior art multi-link PPP bundling techniques to add additional dial-in connections. The present uses known multi-link PPP bundling technologies in conjunction with layer 2 forwarding mechanisms to offer a service which is unique to this invention. The unique service being that the edge systems 114 and 115 , which each maintain dial-out connections, can offer the dial-out connections as a multi-link PPP bundle to hosts dialing out from local network 110 . When packets arrive to the multi-link PPP bundle, it is a responsibility of the layer 2 forwarding mechanisms to divide the packets for the remote system 102 amongst each edge system 114 and 115 . Step 407 is a preferred embodiment of the invention as contrasted with step 406 which is an alternative mechanism to allow both connections 120 and 121 to be used to access remote system 102 .
For embodiments implementing Step 406 , Step 408 follows, in which all local systems such as local systems 111 - 113 within local network 110 can choose between the two available advertised routes using either per packet or per destination techniques.
In this manner, processing steps 400 - 409 allow the present invention to offer bandwidth-on-demand features for packets which must be transferred from local network 110 via dial-out connections to a remote network such as remote network 101 .
According to another aspect of the invention, the system of the invention can assist systems which use a feature called “call back”. Generally, call back refers to a system in which a remote system such as remote system 102 places a call to an edge system such as edge system 114 . When the edge system 114 answers the call from remote system 102 , remote system 102 identifies itself to edge system 114 and then hangs up. Edge system 114 then uses a mechanism such as caller identification or uses the AAA server 109 to obtain dialing information for the remote system 102 which just dialed in. Once this information is obtained, the edge system 114 calls back the remote system 102 and establishes a data communications session therewith. This call back process is known in the prior art and is simply used to place the primary calling responsibility onto the edge system 114 rather than the remote system 102 . That is, the remote system 102 simply places a quick short call to the edge system 114 to identify itself and then disconnects the connection. Immediately thereafter, the edge system 114 calls the remote system 102 back and establishes a data communications connection which may last for any length of time thereafter. In this manner, the prior art call back systems simply place the majority of the phone call cost on the edge system 114 . This is useful, for example, within companies which require traveling sales people to dial in to an edge system within the corporate network from anywhere in the country and which want to maintain phone bills which are predominantly charged from a single edge system, rather than having each sales person dial in for an indefinite amount of time while communicating with the company's computer network.
The system of the invention assists in systems which use the call back feature in that if the initial call placed by the remote system 102 is placed and answered by an edge system 114 which may be congested or oversubscribed, the system of the invention can pass off the call back responsibility to another edge system which may be less congested or may be less subscribed. That is, the invention as previously described allows an edge system which is aware of a requirement for a connection to be placed to a remote system to pass off this requirement and the connection establishment responsibility to another edge system. As such, in a call back situation, when a remote system 102 dials in, any edge system 1114 , 115 or 116 may answer the call, regardless of its current congestion or subscription rate. However, before the edge system which accepted the initial call from the remote system 102 places a return call, the edge system uses the invention to determine if the capability exists within itself to place the return call. If not, the invention allows the edge system to transfer the call responsibility to another edge system.
Various conditions may exist within an edge system which cause that edge system to pass off call responsibility to another edge system. In one situation, the edge system may simply be congested and may not have enough processing power to handle additional dial-out capabilities. An over subscription condition may occur in which the edge system which answered the dial-in call contains no dial-out ports available to place the return call to the remote system.
Another condition which may trigger a dial-out call handoff is that the class of the remote system 102 which makes the initial dial-in attempt may be low. That is, remote system 102 which makes the initial dial-in connection may only have an associated level of service for a low speed connection. However, the edge system which may have happened to answer the call may only provide dial-out connections of a very high speed or high data rate. As such, the edge system which answered the call can use the invention to cause another edge system which handles lower priority remote system call backs to perform the dial-out call back connection.
Another selection criteria which may trigger use of the invention in a call back scenario is based on the cost of the return call back. As an example, suppose a single edge system is provided with an 800 number which may be used nationwide for any remote system to perform the initial dial-in step. When the initial dial-in step is performed from anywhere in the country, the single 800 number associated with the edge system answers the call. The edge system uses a mechanism such as caller ID to determine the exact geographical location of the remote system 102 based on area code, for example. Once the geographical location of the remote system requesting a call back is known, the edge system which answered the call can direct an edge system located within close proximity to the remote system awaiting a call back to make the call back. In this manner, no matter which geographical location a remote system calls in from, the system of the invention can ensure that a call back to that remote system is made from an edge system which is located as close as possible to the remote system in order to minimize call back costs.
While this invention has been described as allowing an edge system within a single stack group 117 to provoke other edge systems within the same stack group to place dial-out calls, the invention is not limited as such. That is, if edge system 114 in stack group 117 is congested, oversubscribed or requires more bandwidth-on-demand, the edge system 114 may select other edge systems in other stack groups which are not shown in FIG. 1 to be the secondary edge systems which place the dial-out call to the remote system. The alternate list 162 shown in FIG. 2 may maintain a list of edge systems either within a single stack group or within an entire local network 110 which may be used for transmission of the SGBP dial-out request message (i.e., step 306 in FIG. 3 ).
While this invention has been particularly shown and described with references to preferred embodiments 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. | A method and apparatus providing improved service in IP networks requiring switch circuit connections by allowing many local systems to establish a switched circuit connection to a remote system without using equal cost routing. The invention detects when a system is over-subscribed (no circuits available for dial-out), congested (lacking other resources to provide dial-out), or more band-width is demanded, and scales to the demand by forcing dial-out from an alternative system. Existence of the new connection is made available to existing systems by updates to system routing tables. The scaling capability is also used to address incoming calls that require a callback from the most appropriate system. | 7 |
BACKGROUND OF THE INVENTION
This application is a continuation-in-part application of Ser. No. 06/681,071 which was filed Dec. 12, 1984, which was a continuation of Ser. No. 06/579,805 filed Feb. 17, 1984, now abandoned, which was a continuation of Ser. No. 06/221,219 filed Dec. 30, 1980, now abandoned.
Previous marsh building methods involve the placement of material in relatively shallow waters by the discharge from a dredge pipe of a slurry at high volume and low pressure being supplied from a suction dredge. The pumped slurry discharged from the dredge pipe end, by gravity, is dispersed over the region adjacent the pipe outlet. This method of dispensing of the pumped material results in an island located adjacent the dredge pipe outlet, and a series of islands as the pipe is successively moved over the area to be built. The composition of the material of these islands varies in that the heavy and denser material of the slurry would not flow far from the pipe outlet, but the finer and more desirable organic materials would flow a greater distance from the pump outlet running off into the valleys of lower elevation. Thus, at each location of the dredge outlet an island is formed having the denser materials located adjacent the island center, while the lighter and finer materials, particularly those of organic composition, would be located at the outer regions of the island.
After drying, leveling or mixing of the material of the islands is usually impractical because of their location, and the expense involved. The islands become permanent to the built-up marsh or upland and the reconstructed land does not have a consistent composition throughout its area, which affects the vegetation and marsh development, and also produces an inconsistent density permitting holes, hard spots, knolls and the like as the finer material usually washes away.
Attempts have been made to control island building and uneven distribution of the pumped material by the use of containment ponds receiving the slurry. However, the use of containment ponds to improve the consistency of material distribution has been relatively ineffective as the discharge of the slurry into a confined body of water still permits separation of the different sizes of particles and an uneven buildup of material is difficult to prevent.
For successful marsh building it is very important that a desired predetermined elevation be achieved as the desired habitat and vegetation only occurs in a limited elevational range subject to the proper flow and ebb of water flooding. With conventional marsh building techniques, it is difficult to maintain the desired elevations because of the uneven impermanent distribution and the spot segregation of the deposited material and the inability to accurately obtain sloping placements for transition zones.
Similar problems exist in the nourishment of beaches. The rebuilding or nourishment of beaches is normally accomplished by pumping sand dredged from an offshore location through a pipe onto the beach. The sand and water slurry discharged from the pump outlet produces an island about the outlet with the larger and heavier particles closer to the island center while the lighter and finer particles flow a greater distance from the outlet. While these islands are easier to knock down and smooth over when defined on a beach as compared to a marsh, the problem of the inconsistency of material size distribution continues, and beaches renourished in the conventional manner will not have uniform size and weight particle distribution which results in nonlevel elevations as the beach is subjected to waves and rain. Further, because of the non-cohesiveness resulting from the segregation of the pumped material, beaches nourished by conventional methods do not have the original durability.
In the above identified applications method and apparatus is shown for spraying dredged material over a relatively large area wherein the distribution of the dredged material is substantially uniform with respect to particle size and composition, and in these applications the pumped material is distributed as a thin film to produce minimal elevation of the area upon which the material is deposited and thereby have minimal adverse environmental impact. In these applications the disclosed apparatus uses dredged material and high pressure pumps to spray a slurry over an area either adjacent the dredge, or remote from the dredge, and diffusion and nozzle positioning means at the high pressure nozzle outlet may be used to aid in the even distribution of the pumped material over the area being covered. However, in the prior applications, the use of the disclosed apparatus for marsh rebuilding or beach nourishment was not contemplated as the necessary increase in elevation of the area would significantly modify the environment, and not be environmentally acceptable, which is contrary to a basic concept of the prior applications.
It is an object of the invention to provide a method for building marshes or restoring beaches using a pumped slurry wherein the slurried material is evenly distributed over the area whose elevation is to be increased, the composition of the deposited material being substantially uniform with respect to size and weight.
Another object of the invention is to provide a method for building marshes or restoring beaches wherein the distribution of the restoring material is such as to avoid islands and elevational variations other than designed and wherein the composition of the distributed material will be substantially uniform regardless of the deposited distance from the discharge outlet.
Yet another object of the invention is to provide a method for building marshes and restoring beaches using a pumped slurried material wherein the mode of uniformly distributing the material over the area to be built or nourished may be varied to accommodate the particular area configuration.
In the practice of the invention slurrying apparatus which may be stationary or may take the form of a suction dredge located within a waterway having a rotating cutterhead comminuting the material to be used in the marsh building or beach restoration includes powerful pumps for pumping the resultant slurry of material and water to a nozzle located on a distribution barge or platform remote from the slurrying apparatus.
The high pressure nozzle on the distribution platform is elevated to spray the pumped material into the air over the area to be built up. The nozzle is supported on a movable means permitting rotation or oscillation of the nozzle both horizontally and vertically, and a diffuser may be located adjacent the nozzle to disperse the water column projecting therefrom.
The distribution platform may be located offshore of a beach to be nourished, or a marsh area to be rebuilt, and the nozzle moved across the area to be elevated with an alternating sweeping motion. If the area to be elevated is large and not closely defined by boundaries or a shoreline, the distribution platform may be located within this area permitting the nozzle to rotate about a vertical axis through 360° to deposit the material in a circle about the distribution platform.
The operation of the nozzle may be remotely controlled, and the dispersed material will fall like rain or mist over the area to be elevated thereby producing a uniform distribution of the material without segregation regardless of the distance from the distribution nozzle.
BRIEF DESCRIPTION OF THE DRAWINGS
The aforementioned objects and advantages of the invention will be appreciated from the following description and accompanying drawings wherein:
FIG. 1 is a plan view of the suction barge and distribution barge wherein the distribution barge is mounted off-shore of the area to be elevated,
FIG. 2 is a side elevational view of a typical suction barge used in the practice of the invention,
FIG. 3 is an enlarged, detail, plan view of the distribution barge,
FIG. 4 is an elevational view of the distribution barge, and
FIG. 5 is a plan view of an arrangement wherein the distribution barge is mounted in the center of the area to be elevated.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The invention pertains to the method of building marshes and beaches and the particular source for the building material does not constitute an aspect of the invention. In the building of marshes, inorganic material, sand, silt, consolidated spoils, comminuted organic vegetation and upland material, and the like, may be employed. In the building or restoration of beaches sand comprises the principle ingredient of the building material.
The marsh and beach building material is sprayed over the area being built-up by high pressure pumps, and accordingly, must be in a pumpable form, such as a slurry consisting of the solid material and water. This slurry may result from the dredging of natural bottom material from a body of water by a suction dredge, or may be produced by other slurry producing apparatus of conventional nature. For instance, the slurry may be produced by pumpable solid material and water being mixed in a large tank or receptacle and pumped therefrom, or the pumpable material may be deposited in a pond or body of water and removed therefrom by a suction dredge. The particular manner by which the slurry is formed does not constitute a part of the present invention and it is to be understood that conventional slurry producing apparatus may be used in the practice of the invention.
The most common, and economical, method for producing the slurry for building marshes and beaches is to use a suction dredge which is dredging the natural bottom of a body of water near the area to be built up, or the suction dredge could be located in a pond to which solid material is being transported and deposited.
In the drawings a suction dredge is shown by way of illustration as the source of the slurried material and the suction dredge 10 includes a ladder 12 supporting a cutterhead 14 which may be raised or lowered by the ladder by hydraulic cylinders, not shown. A pump 16 mounted on the barge communicates with the cutterhead 14 through suction line 18 and draws the comminuted material from the cutterhead into the pump 16 for discharge through the high pressure pipe or hose 20. The barge 10 is propelled by propellers 22 and the details of the cutterhead 14 form no part of the instant invention, and this apparatus may take the form shown in my U.S. Pat. No. 3,971,148.
The pipe or hose 20 is of a generally flexible type and includes floats 24 and is of considerable length wherein the suction barge may take a number of passes while supplying a single location of the distribution barge.
In FIG. 1 the distribution barge 26 is shown as located anchored slightly offshore of an area 28 defined by a shoreline 30, which may constitute an area in which a marsh is to be built, or a beach built or renourished.
The distribution barge 26 may be held in position by deadmen 32, or otherwise anchored, and includes a deck 34 having a nozzle support upright 36 vertically mounted thereon. The support 36 includes a manifold 38 communicating with the conduit 40 which communicates with the fitting 42 mounted on the barge to which the supply pipe 20 is affixed.
A nozzle 44 is pivotally attached about a horizontal axis to the upper region 46 of the upright 36 and in communication with the upright so as to receive the pressurized slurry from the manifold 38. The manifold 38 is of the rotary type wherein the upper region 46 of the nozzle support may rotate through 360° about a vertical axis.
The direction of discharge of the nozzle 44 may be either controlled from the distribution barge 26 or from the suction barge 10, remotely, and to this end, a control unit 48 is mounted upon the distribution barge deck which is connected to a self-contained power unit 50 also mounted on the barge and controlled by control line 52 attached to the pipe 20 at fitting 42 and extending to the suction dredge 10. The control unit 48 through solenoid valves, not shown, controls the expansible motor 54 mounted upon the upper region 46 of the nozzle support which adjusts the elevation of the nozzle 44, and a rotary hydraulic motor 56 affixed to the upper region 46 of the nozzle support and controlled by unit 48 will rotate the nozzle about its vertical axis to control the horizontal direction of distribution. Manually operated controls 58 are included on the control unit 48 whereby an operator on the distribution barge may directly control the direction of discharge of the nozzle 44.
A diffuser 60, FIG. 4, is mounted adjacent the nozzle discharge end which consists of a projection, such as threaded rod 62, adjustably located within the stream of slurry being discharged from the nozzle 44 to further diffuse the stream in addition to that diffusion occurring at the nozzle and as the slurry is sprayed through the air.
In most cases booster pumps, not shown, are located along the pipe 20, or upon the distribution barge 26, to restore the pressure loss in the pipe and assure a high pressure at nozzle 44. Such booster pumps are of conventional form and their use is known in dredging operations.
In operation, the suction dredge 10 will be operating at a location in the proximity of the distribution barge 26, but generally remote therefrom, and will be connected to the distribution barge by means of the floating hose or pipe 20. The discharge from the suction dredge operation is pumped, under high pressure, into the pump 16 to the distribution barge fitting 42.
The pressurized slurry enters the manifold 38 and is discharged through the nozzle 44 which is directed toward the area 28 to be elevated. The nozzle 44 will, in the arrangement shown in FIG. 1, be oscillated up and down and in a back-and-forth movement to distribute the sprayed material over the area 28, and the elevation of the nozzle will be relatively high so that the slurry will fall rain-like in a relatively fine mist and thereby be uniformly distributed over the area assuring a uniform elevation buildup. The slurry distribution can also be varied by increasing or reducing the pumping pressure. The oscillation of the nozzle is produced by the motor 56 and control unit 48, and may be under manual or automatic operation. If under manual control, care will be taken to assure that the nozzle is kept moving to prevent uneven distribution of the sprayed material.
Of course, the degree of buildup that will occur at area 28 will be determined by the desired specifications. However, in the practice of the invention the increase in elevation of area 28 will be at least 2 inches, and it is the expectation that the elevation will be relatively significant, and be of a foot or greater.
When elevating an area such as at 28 having an "active" shoreline it may be advisable to erect a containment dike or screen 64 to restrain the finely dispersed slurry adjacent the shoreline from dissipating into the water at the shoreline. Such a screen or dike may consist of panels or the like held in position by posts 66, and, if desired, this dike may be removed after the sprayed material has settled and consolidated.
In the arrangement shown in FIG. 5, a relatively large area to be elevated is represented at 68, and this arrangement will normally be used with building a marsh. The shoreline is indicated at 70, and the distribution barge 26 is located centrally within the area 68. The nozzle 44 is connected to the supply pipe 20 attached to the suction dredge, not shown, and the nozzle will be slowly rotated by the motor 56 in a clockwise or counterclockwise direction to distribute the slurry 360° about the distribution barge and the vertical angle of the nozzle 44 will be varied periodically to insure uniform slurry distribution. In this manner a maximum area is covered with a uniform distribution of slurry and attention by the operator is minimized. By adjustment of the diffuser 60 and the angle of the nozzle 44, a rain-like distribution of the material over the area 68 is possible wherein the composition of the sprayed material will be substantially uniform throughout the area.
Once the area 68 has been built up to the desired elevation, the distribution barge 26 is moved to the next area, which may be adjacent thereto, and the operation repeated. If the area 68 is solid enough the nozzle 44 and associated apparatus may be mounted on other types of platforms than a barge, for instance, a land-supported vehicle, amphibious vehicles, marsh buggies, ground effect vehicles, etc., would also facilitate movement between adjacent area to be built up.
It will be appreciated that the practice of the method of the invention permits marshes to be built, and beaches to be restored, wherein close elevational control of the area being built up may be maintained. The spraying distribution of the slurry, and the rain-like dispersion thereof permits a substantially uniform composition to be distributed over relatively large areas without segregation, and it is appreciated that various modifications to the invention may be apparent to those skilled in the art without departing from the spirit and scope of the invention. | The invention pertains to a method for the building or restoration of marshes and beaches wherein a slurry of solid material and water is formed at one location and pumped to a remote location for uniform distribution of the slurry over a large area to substantially increase the elevation for the purpose of building a marsh, restoring a beach, or the like. The slurry is distributed by a high pressure nozzle uniformly directing a spray which falls in a mist over the area on which the slurry is deposited to produce a significant elevational increase in the area. The nozzle may make alternate directional sweeps, or rotate in a common direction to cover a circular area, with various adjustable vertical angles and pressure variations to control distribution. | 4 |
FIELD OF THE INVENTION
The invention concerns an air-conducting system for a tractor and/or trailer, wherein at least one of the vehicles has a wind deflector.
BACKGROUND OF THE INVENTION
The tractor and the trailer in the coupled together condition form a road train. Road trains in the form of a semitrailer or articulated train generally have a maximum transport volume. For this, the cargo space is configured in box shape, but it must satisfy legal requirements in regard to its dimensions. The desire for maximum transport volume on the one hand and observance of legal requirements in terms of outside dimensions on the other hand complicate the design of aerodynamically favorable vehicle shapes and thus a reduced fuel consumption or emission of pollutants.
Wind deflectors are known from the prior art to lessen the aerodynamic drag, being arranged on the roof of the tractor and able to adjust their inclination by motor in order to adapt themselves to the different heights of the trailer or become as flat as possible when driving empty.
WO 20061029732A1discloses one such wind deflector on the roof of the tractor of a semitrailer, which is furthermore outfitted with a shifting mechanism for a fifth wheel. When driving slow, the fifth wheel can move to the rear on the tractor, so that a wider gap is adjusted between the front wall of the trailer and the rear wall of the driver's cabin, which is advantageous for maneuvering and traveling tight curves. To reduce the aerodynamic drag when traveling fast and in a straight line, this gap can be reduced by moving the fifth wheel in the direction of the driver's cabin, thus reducing the concomitant turbulence at the gap. The wind deflector arranged on the roof should likewise be connected to the control unit of the shifting mechanism and thus be adjustable in its inclination to the size of the gap, so that the inclination is more flat for a large gap and more steep for a narrow gap.
In practice, however, it turns out that the placement of a wind deflector located on the roof of the driver's cabin is not enough to reduce the aerodynamic drag in the desired degree.
SUMMARY OF THE INVENTION
For this reason, the problem of the invention was to bring about a reduction of the aerodynamic drag by other means.
The problem is solved according to the invention with an air-conducting system in which the wind deflector is arranged at the rear and/or in the front region and it can be adjusted in dependence on the driving speed. By an installation position “at the rear” of the vehicle is meant the tailgate of the cargo structure, while the wind deflector should be arranged especially effectively at the upper edge toward the roof wall and/or the edges toward the side walls.
By the installation position “in the front region” is meant the zones that lie in front of the vehicle and whose configuration is of importance to the creation of the flow about the vehicle or for the way in which the flow passes over the vehicle.
The claimed wind deflectors have in common that in the deployed working position they bring about a lengthening of the tractor or of the semitrailer or articulated trailer.
Consequently, the installation position for the wind deflector in the tractors of articulated trailers is located at the rear end of the tractor, which accomplishes a reduction in the aerodynamic drag to a particular extent, even when driving without a towed vehicle. When driving with a towed vehicle, or in the case of semitrailers, the wind deflector is arranged at the upper rear edge of the trailer vehicle.
Especially during fast driving on the freeway, there is a massive pressure gradient between the air flowing above the vehicle and the region behind the vehicle contour, which creates a far-reaching wake turbulence. With the help of the tilting of the wind deflector adapted to the driving speed, the turbulence at the rear of the vehicle can be minimized.
Wind deflectors arranged in the front region ensure a favorable flow around the areas of the vehicle situated behind them.
Advantageously, the wind deflector is connected to an electronic control unit. With the help of the control unit, the position of the wind deflector can be controlled especially favorably. It is possible to store in the electronic control unit appropriate characteristics for the angle of attack or the shape of the wind deflector for the different driving situations. Furthermore, a “cargo mode” can be stored in the control unit for the loading and unloading, when the wind deflector is swiveled away from the access zone behind the cargo space.
The electronic control unit should have an interface by which vehicle signals can be transmitted to the control unit. The signals can be provided to the electronic control unit, for example, from the vehicle control unit, while the actual driving speed, but also the steering wheel angle and/or the axle load, preferably serve as the signals.
Preferably, an adjusting mechanism is arranged on the tractor, with which the relative position of tractor and trailer can be changed in the vehicle lengthwise axis during driving operation. Usually the cargo volume is already maximized in the design of the vehicles, such that the legally permitted overall length of the road train is achieved. In this case, a wind deflector arranged in the rear would result in an exceeding of the maximum permitted vehicle length in the swiveled-out position.
But insofar as an adjusting mechanism is present, which pulls the trailer up to the tractor during straight travel and thereby minimizes the gap between the two vehicles in aerodynamically favorable fashion, the shortening of the length of the road train is utilized as swivel room for the wind deflector, without exceeding the permitted vehicle length.
With the preferred embodiment under discussion a method for reducing the aerodynamic drag of a road train was also developed, in which a wind deflector and an adjusting mechanism for changing the relative position of tractor and trailer in the vehicle lengthwise axis are provided, wherein the trailer during straight travel of the road train is pulled from a rear position to a forward position and the space thus freed up in the rear or front region is used by the wind deflector to swivel out. The maximum permissible vehicle length is always observed in this way.
When braking or traveling on a curve, the distance between the vehicles is increased and the wind deflector is at least partly retracted to reduce the overall length of the road train.
According to one favorable embodiment, the adjusting mechanism is a shifting mechanism for a fifth wheel. The fifth wheel is supported by its two bearing blocks on a carriage, which is guided in the vehicle lengthwise direction on two parallel rails and can generally be locked relative to them. The shifting mechanism furthermore comprises an actuating means, such as a hydraulic cylinder, which allows the trailer to move during vehicle operation against the direction of travel and thereby pulls the trailer up to the driver's cabin of the tractor. Before moving the fifth wheel, another actuating cylinder can be used to lift the usually form-fitting lock between carriage and rails. The gap between the vehicles should only be reduced in driving operation during fast straight-line travel. During maneuvering or panic braking, the maximum gap between the vehicles must be restored in the shortest of time, in order to avoid the trailer from striking against the tractor.
Likewise, the adjusting mechanism can be a shifting mechanism for a trailer coupling, if the invention is implemented on an articulated train. In this case, the trailer coupling is first pulled under the tractor against the direction of travel.
If the structural space underneath, the tractor is not enough, instead of the movable vehicle coupling one can also design the complementary coupling components of the trailer to be movable.
Advisedly, the adjustment mechanism is connected to the control unit. Thus, a common control unit controls both the adjustment mechanism and the rear wind deflector, so that an especially prompt adapting of the position of the wind deflector to the actual position of the trailer is accomplished.
Advantageously, the rear wind deflector is configured in the form of a flap. In this embodiment, the wind deflector swivels about a horizontal axis and in the retracted position approaches the rear of the cargo space. In this retracted position, the semitrailer or articulated train has its shortest vehicle length and even in the rearmost position of the trailer it fulfills the legal requirements in regard to the maximum permissible vehicle length. When the trailer is pulled forward during driving operation, the wind deflector in flap form swivels about its hingelike fastening and positively influences the adjacent air flow.
Alternatively, the wind deflector can comprise inflatable air-conducting element. These can be fed, for example, via the pneumatic supply system of the trailer. Especially preferable is a combination of the flap form and air-conducting elements located underneath in the form of an air bellows.
According to another alternative embodiment, the wind deflector has telescoping air-conducting elements. These are comparable to extensible landing flaps on an airplane wing and can also be retracted in several steps, thus saving space. A major advantage of the telescoping air-conducting elements is that the space behind the vehicle remains free and the air-conducting elements do not get in the way when loading and unloading.
Extensible flap systems can also be considered for the front wind deflector. However, inflatable air-conducting elements are especially advantageous, since these act as buffers in event of a collision.
BRIEF DESCRIPTION OF THE DRAWINGS
For a better understanding, the invention shall now be explained more closely by means of nine figures. There are shown:
FIG. 1 , a schematic side view of a semitrailer with trailer moved backward and wind deflectors retracted;
FIG. 2 , a view per FIG. 1 with trailer moved forward and wind deflectors extended;
FIG. 3 , a schematic side view of an articulated train with trailer moved backward and wind deflectors retracted;
FIG. 4 , a view per FIG. 3 with trailer moved forward and wind deflectors extended;
FIG. 5 , an enlarged side view of a wind deflector arranged at the rear according to a first embodiment;
FIG. 6 , an enlarged side view of a wind deflector arranged at the rear according to a second embodiment;
FIG. 7 , an enlarged side view of a wind deflector arranged at the rear according to a third embodiment;
FIG. 8 , a side view of a wind deflector arranged in the front region according to a first embodiment, and
FIG. 9 , a side view of a wind deflector arranged in the front region according to a second embodiment.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows a schematic side view of a semitrailer 3 formed from a tractor 1 and a trailer 2 mechanically coupled to it by a fifth wheel 11 .
The trailer 2 lies on the fifth wheel 11 by a bearing plate 20 in its forward section and is additionally connected detachably to the fifth wheel in customary fashion by a king pin (not shown). For goods transport, the trailer 2 has a cargo space 21 , which is bounded at the top by a roof wall 19 and at its rear end by a tailgate 6 a.
According to the invention, a wind deflector 4 a with a flap 15 is situated on the roof edge 23 in the transition zone from the roof wall 19 to the tailgate 6 a . The flap 15 can swivel about a pivot axis 24 running parallel with the roof edge 23 (see FIG. 5 ). With the help of the flap 15 , turbulence occurring at the rear 6 a of the trailer 2 and thus the fuel consumption of the semitrailer 3 can be reduced.
The representation of FIG. 1 shows the fifth wheel 11 in a rear position on an adjusting mechanism 9 , which is configured as a shifting mechanism 10 of the fifth wheel 11 . The shifting mechanism 10 comprises guide rails 25 running at least in the direction of travel and a pressurized cylinder (not shown), by which the position of the fifth wheel 11 on the guide rails 25 can be adjusted in the lengthwise direction. In the position of the fifth wheel according to FIG. 1 , the overall semitrailer 3 has its maximum length.
The shifting mechanism 10 is connected to a control unit 7 and receives a signal from it during driving operation to move the fifth wheel 11 as close as possible to the driver's cabin 22 of the tractor 1 . This reduces turbulence of the air flow thanks to the gap S between driver's cabin 22 and trailer 2 . This process does not need to be initiated by the driver, since the control unit 7 receives signals from the vehicle control unit (not shown) via an interface 8 that take into account in particular the actual speed of travel,
FIG. 2 shows the semitrailer 3 in driving operation on a straight stretch of road. This usually occurs on freeways and usually involves a high speed of travel, where the wind deflector 4 a works especially effectively on the air flowing around the rear 6 a and minimizes turbulence.
During rapid straight travel, the trailer 2 has been pulled via the adjustment mechanism 9 up to the driver's cabin 22 from the rear position Pos 1 to the forward position Pos 2 along the movement path x. This reduces the gap S between tractor 1 and trailer 2 , as well as the overall length of the semitrailer by the amount of the movement path x, so that the wind deflector 4 a has available exactly the same movement path y 1 for swiveling, without exceeding the legally mandated maximum length of the semitrailer 3 .
As a supplement to the wind deflector 4 a swiveled out at the rear 6 a of the trailer 2 , the tractor 1 also has two wind deflectors 4 b arranged in the front region 27 . In the extended working position shown, these wind deflectors 4 b lengthen the tractor 1 and thus the overall semitrailer 3 toward the front. One of the wind deflectors 4 b arranged in the front region is situated in a vertical section between the windshield and the bumper. The second wind deflector 4 b arranged in the front region 27 is positioned above this and conducts the air flow away across the driver's cabin 22 .
If no wind deflector 4 a is present or activated on the trailer 2 , the wind deflectors 4 b in the front region 27 each have available, as maximum path of movement, the movement path y 2 corresponding to the movement path x of the trailer 2 . If both a wind deflector 4 a at the rear 6 a of the trailer 2 and a wind deflector 4 b in the front region are used together, the sum of the movement paths y 1 , y 2 can correspond at most to the movement path x of the trailer 2 .
FIG. 3 shows the invention on an articulated train 5 , which likewise consists of a tractor 1 and a trailer 2 , in a starting position. Unlike a semitrailer 3 , both the tractor 1 and the trailer 2 of the articulated train 5 are configured with a cargo space 21 . The trailer 2 is mechanically coupled to the tractor 1 by a hitch 14 with a trailer coupling 13 .
After attaining a minimum speed that is stored in the control unit 7 , a wind deflector 4 c arranged at the rear 6 b of the tractor 1 moves from a folded to an extended position. When the tractor 1 is driving without a trailer 2 , this substantially diminishes the turbulence at the tailgate 6 b of the tractor 1 .
The wind deflector 4 b arranged in the front region 27 is in a resting position and integrated into the contour of the tractor 1 .
If a trailer 2 is additionally coupled on, the wind deflector 4 c of the tractor 1 bridges the gap S and minimizes turbulence between the tractor 1 and the trailer 2 .
The trailer 2 also has a wind deflector 4 a at the roof edge 23 , which is folded against the tailgate 6 a in the starting position shown in FIG. 3 . This is necessary so that the maximum length of the articulated train 5 is not exceeded.
FIG. 4 shows the articulated train 5 during fast straight-line travel, where the trailer coupling 13 is drawn by means of a shifting mechanism 2 underneath the chassis of the tractor 1 and has thereby moved the trailer 2 from position Pos 1 to Pos 2 by the amount of the movement path x. As a result, the length of the articulated train 5 was reduced during driving, so that the wind deflector 4 a can likewise be extended. The wind deflector 4 a now has available to it the same movement path y 1 in terms of magnitude as the movement path x, without exceeding the maximum permitted length of the articulated train 5 . However, the movement path y 1 cannot be utilized to the full extent if the wind deflector 4 b of the tractor 1 was additionally extended in the front region 27 . The wind deflector 4 b serves to extend the original contour of the tractor 1 and guide the air flow around the structures located behind it. In this case, the sum of the movement paths y 1 , y 2 can correspond at most to the movement path x of the trailer 2 .
FIGS. 5 to 7 show sample wind deflectors 4 a , which could basically be mounted in identical design as wind deflectors 4 c on the tailgate 6 b of the tractor 1 .
The embodiment disclosed in FIG. 6 concerns a wind deflector 4 a in the form of a flap 15 , which is mounted and can swivel on the rear edge 23 of the abutting roof wall 19 and tailgate 6 a . The pivot axis runs parallel to the dimension of the roof edge 23 or transverse to the direction of driving. The angle of attack of the flap 15 can be varied by means of an actuator 18 . The actuator 18 , in particular, is a fluid-operated cylinder, especially preferably a pneumatic cylinder.
FIG. 5 shows an alternative embodiment, in which the wind deflector 4 a is configured as an inflatable air-conducting element 16 , corresponding to FIG. 7 . Once a sufficient movement path y 1 is available for the extending of the wind deflector 4 a (see FIG. 2 , 4 ), the air-conducting element 16 is activated with pressurized air, for example, from the pressurized air system of the semitrailer or articulated train 3 , 5 . After reaching a minimum pressure, the inflatable air-conducting element 16 lifts up and assumes its intended shape. The retracting of the air-conducting element 16 is done by releasing the air contained therein.
According to a third alternative embodiment, the wind deflector 4 a can also be configured as a telescoping air-conducting element 17 . In this case, at least two segments 26 move relative to each other and thereby bring the telescoping air-conducting element 17 into an extended working position.
FIG. 8 shows a tractor 1 with two wind deflectors 4 b in flap form 15 , one above the other, in the retracted resting position and the extended working position (broken line). For an especially effective conducting of the air, the lower wind deflector 4 b additionally has an apron 28 , which is deployed by the extending of the flap 15 .
FIG. 9 shows an alternative embodiment of the wind deflectors 4 b located in the front region 27 , which comprise inflatable air-conducting elements 16 and assume their intended shape by receiving pressurized air. This embodiment offers the additional benefit of a cushioning in event of collisions when mounted in the front region 27 .
LIST OF REFERENCE SYMBOLS
1 tractor
2 trailer
3 semitrailer
4 a wind deflector, trailer
4 b wind deflector, tractor front
4 c wind deflector, tractor rear
5 articulated train
6 a rear/tailgate, trailer
6 b rear/tailgate, tractor
7 control unit
8 interface
9 adjusting mechanism
10 shifting mechanism, fifth wheel
11 fifth wheel
12 shifting mechanism, trailer coupling
13 trailer coupling
14 hitch
15 flap
16 inflatable air-conducting elements
17 telescoping air-conducting elements
18 actuator
19 roof wall
20 bearing plate
21 cargo space
22 driver's cabin
23 roof edge
24 pivot axis
25 guide rails
26 segment, air-conducting element
27 front region
28 apron
Pos 1 rear position, trailer
Pos 2 forward position, trailer
x movement path of trailer
y 1 movement path, rear wind deflector
y 2 movement path, front wind deflector
S gap between vehicles | An air-conducting system for a tractor and/or trailer is described, wherein at least one of the vehicles has a wind deflector. The problem addressed by the invention was to improve the aerodynamic drag of tractors and/or trailers. The problem is solved according to the invention by an air-conducting system in which the wind deflector is arranged at the rear of the trailer and/or at the rear and/or in the front region of the tractor and can be adjusted depending on the driving speed. | 1 |
BACKGROUND OF INVENTION
Meniscus repairs have been shown to be effective, especially with tears in the peripheral one-third of the meniscus. Various techniques have evolved to perform this demanding procedure. Initially, open repairs were done that proved the feasibility of the procedure. Subsequently, several techniques involving the arthroscope were developed to assist in these repairs. Most of the techniques have been a variation of the outside-in, or more commonly, the inside-out techniques. These repair procedures have shown to be technically demanding, but more importantly, have inherent risks to the neurovascular structures about the knee. Most of the techniques describe an ancillary incision, either medial and/or lateral, for the purpose of performing the repair and specifically to protect these important structures. In addition, these repairs tether the posterior capsule, causing extension difficulties in the post-operative rehabilitation phase.
Accordingly, there exists a need for an assembly for meniscal repair that reduces the difficulties and time to repair the meniscus.
SUMMARY OF INVENTION
According to one aspect of the present invention, there is provided an assembly for meniscal repair including a first tissue fixation member configured to secure a meniscal tissue, a suture anchor having a proximal end, a distal end, a central axis defined therethrough, an eyelet, and a textured outer surface, and a first suture configured to be coupled to the first tissue fixation member and configured to be received through the eyelet of the suture anchor.
According to another aspect of the present invention, there is provided a method for meniscal repair including providing a first tissue fixation member configured to secure a meniscal tissue, a suture anchor having an eyelet, and a first suture, securing the first suture to the first tissue fixation member, securing the first tissue fixation member to a meniscal tissue, threading the first suture through the eyelet of the suture anchor, securing the suture anchor within a bone, and tensioning the first suture within the suture anchor.
According to another aspect of the present invention, there is provided a kit for meniscal repair including at least one tissue fixation member configured to secure a meniscal tissue, a suture anchor comprising an eyelet, at least one suture configured to be coupled to the at least one tissue fixation member and configured to be received through the eyelet of the suture anchor, and a delivery device configured to assist with delivery of the at least one tissue fixation member into a body.
BRIEF DESCRIPTION OF DRAWINGS
FIGS. 1A-1C are multiple views of an assembly for meniscal repair in accordance with embodiments disclosed herein.
FIG. 2 is an illustration of a suture anchor and associated plug.
DETAILED DESCRIPTION
The following is directed to various exemplary embodiments of the disclosure. Although one or more of these embodiments may be preferred, the embodiments disclosed should not be interpreted, or otherwise used, as limiting the scope of the disclosure, including the claims. In addition, those having ordinary skill in the art will appreciate that the following description has broad application, and the discussion of any embodiment is meant only to be exemplary of that embodiment, and not intended to suggest that the scope of the disclosure, including the claims, is limited to that embodiment.
Certain terms are used throughout the following description and claims refer to particular features or components. As those having ordinary skill in the art will appreciate, different persons may refer to the same feature or component by different names. This document does not intend to distinguish between components or features that differ in name but not function. The figures are not necessarily to scale. Certain features and components herein may be shown exaggerated in scale or in somewhat schematic form and some details of conventional elements may not be shown in interest of clarity and conciseness.
In the following discussion and in the claims, the terms “including” and “comprising” are used in an open-ended fashion, and thus should be interpreted to mean “including, but not limited to . . . .” Also, the term “couple” or “couples” is intended to mean either an indirect or direct connection. Thus, if a first component is coupled to a second component, that connection may be through a direct connection, or through an indirect connection via other components, devices, and connections. Further, the terms “axial” and “axially” generally mean along or substantially parallel to a central or longitudinal axis, while the terms “radial” and “radially” generally mean perpendicular to a central, longitudinal axis.
Referring generally to FIGS. 1A-1C , an assembly for meniscal repair 100 , according to embodiments disclosed herein, is shown. In one or more embodiments, the assembly 100 may include a first tissue fixation member 101 configured to secure a meniscal tissue 130 , a suture anchor 110 having a proximal end 111 , a distal end 112 , a central axis 150 defined therethrough, an eyelet (not shown), and a textured outer surface, and a first suture 105 configured to be coupled to the first tissue fixation member 101 and configured to be received through the eyelet of the suture anchor 110 .
In one or more embodiments, the first tissue fixation member 101 may be a substantially rigid, bar or rod-shaped member. Alternatively, in one or more embodiments, the first tissue fixation member 101 may have a curved shape and may be formed from a flexible material, such as a plastic or polymer. In one or more embodiments, the first tissue fixation member 101 may be formed from any biocompatible material known in the art, including plastics, polymers, metals, and any combination thereof. The first tissue fixation member 101 may engage with the meniscal tissue 130 and may be used to secure the meniscal tissue 130 , e.g., against a tibia 125 .
In one or more embodiments, the assembly 100 may also include a second tissue fixation member 102 configured to secure the meniscal tissue 130 . In one or more embodiments, the second tissue fixation member 102 may be substantially identical to the first tissue fixation member 101 . For example, as discussed above, in one or more embodiments, the second tissue fixation member 102 may be a substantially rigid, bar or rod-shaped member. Alternatively, in one or more embodiments, the second tissue fixation member 102 may have a curved shape and may be formed from a flexible material, such as a plastic or polymer. In one or more embodiments, the second tissue fixation member 102 may be formed from any biocompatible material known in the art, including plastics, polymers, metals, and any combination thereof. The second tissue fixation member 102 , like the first tissue fixation member 101 , may engage with the meniscal tissue 130 and may be used to secure the meniscal tissue 130 , e.g., against a tibia 125 . Those having ordinary skill in the art will appreciate that more than two tissue fixation members may be used in the assembly 100 to assist with securing the meniscal tissue 130 . For example, three, four, five, or more tissue fixation members, that may be substantially identical to the first tissue fixation member 101 and the second tissue fixation member 102 , may be used in the assembly 100 to assist with securing the meniscal tissue 130 .
As shown in FIG. 1A , the first suture 105 is coupled to the first tissue fixation member 101 . Further, as shown, a second suture 106 is coupled to the second tissue fixation member 102 . In one or more embodiments, each of the first tissue fixation member 101 and the second tissue fixation member 102 may include holes, or notches, formed therethrough, through which each of the first suture 105 and the second suture 106 may be engaged with, or coupled to, the first tissue fixation member 101 and the second tissue fixation member 102 , respectively. Those having ordinary skill in the art will appreciate that the first suture 101 and the second suture 102 may be formed from any material known in the art. For example, in one or more embodiments, each of the first suture 101 and the second suture 102 may be formed from a biocompatible polyester or polyester closure tape and may be, for example, a single or double-arm 2-0 braided non-absorbable polyester suture.
As shown in FIGS. 1B and 1C , the suture anchor 110 includes an eyelet (not shown), in which each of the first suture 105 and the second suture 106 are configured to be received through the eyelet of the suture anchor 110 . In one or more embodiments, the eyelet of the suture anchor 110 may be a transverse hole that is located between the proximal end 111 and the distal end 112 of the suture anchor 110 , and may be formed through the suture anchor 110 . Further, as shown, the eyelet may be located near the distal end 112 of the suture anchor 110 . However, those having ordinary skill in the art will appreciate that the eyelet may be located at any other position on the suture anchor 110 , and that the eyelet is not limited to being formed near the distal end 112 of the suture anchor 110 . For example, the eyelet may be formed near the proximal end 111 of the suture anchor 110 or through a region of the suture anchor 110 between the proximal end 111 and the distal end 112 of the suture anchor 110 . Those having ordinary skill in the art will appreciate that more than one suture anchor 110 may be included in the assembly 100 . For example, two, three, or more suture anchors that may be substantially identical to the suture anchor 110 may be included in the assembly 100 .
In one or more embodiments, the textured outer surface of the suture anchor 110 may be formed near the distal end 112 of the suture anchor 110 . However, those having ordinary skill in the art will appreciate that the textured outer surface of the suture anchor 110 may be formed any other surface of the suture anchor 110 and that the textured outer surface of the suture anchor 110 is not limited to being formed near the distal end 112 of the suture anchor 110 . For example, in one or more embodiments, the textured outer surface of the suture anchor 110 may be formed on the entire outer surface of the suture anchor 110 . Alternatively, in one or more embodiments, the textured outer surface of the suture anchor 110 may be formed near the proximal end 111 of the suture anchor.
Further, in one or more embodiments, the textured outer surface of the suture anchor 110 may be a threaded outer surface. In one or more embodiments, the textured outer surface of the suture anchor 110 may be a threaded outer surface that may be configured to self-tap into a bone, e.g., the tibia 125 . For example, as will be discussed below, a hole may be formed into the tibia 125 . Subsequently, in one or more embodiments, the suture anchor 110 may be aligned with the hole secured within the tibia 125 , such that the threaded outer surface of the suture anchor 110 may engage with, and may form corresponding threads within, the hole formed in the tibia 125 .
Furthermore, in one or more embodiments, the textured outer surface of the suture anchor 110 may be a stepped outer surface. For example, in one or more embodiments, the outer surface of the suture anchor 110 may include steps, or barbs, that may be configured to reduce the possibility of unwanted removal of the suture anchor 110 from a bone, e.g., the tibia 125 . Those having ordinary skill in the art will appreciate that the suture anchor 110 may include any number of steps, or barbs, formed on the outer surface of the suture anchor 110 .
In one or more embodiments, the assembly 100 may also include a fixation plug (not shown) that may be configured to engage with the suture anchor 110 . For example, in one or more embodiments, the suture anchor 110 may include a longitudinal hole formed along the central axis 150 of the suture anchor 110 to receive the fixation plug. In one or more embodiments, the fixation plug may be configured to secure at least one suture, e.g. the first suture 105 and the second suture 106 , within the eyelet of the suture anchor 110 . In one or more embodiments, the longitudinal hole formed through the suture anchor 110 along the central axis 150 of the suture anchor 110 may be a threaded hole. For example, in one or more embodiments, the fixation plug may include corresponding threads that may allow the fixation plug to threadably engage with the suture anchor 110 , i.e., with the longitudinal hole of the suture anchor 110 . As such, in one or more embodiments, the first suture 105 and the second suture 106 may be disposed, or threaded, through the eyelet of the suture anchor 110 . Subsequently, in one or more embodiments, the fixation plug may be engaged within the longitudinal hole of the suture anchor 110 , which may secure the first suture 105 and the second suture 106 within the eyelet of the suture anchor 110 . Those having ordinary skill in the art will appreciate that more than two sutures may be disposed, or threaded, through the eyelet of the suture anchor 110 . For example, three, four, five, or more sutures may be threaded through the eyelet of the suture anchor 110 , and the fixation plug may be engaged within the longitudinal hole of the suture anchor 110 , which may secure any suture disposed through the eyelet of the suture anchor 110 within the suture anchor 110 . Further, those having ordinary skill in the art will appreciate that the fixation plug may not necessarily need to have a threaded outer surface in order to engage with the suture anchor 110 . For example, in one or more embodiments, an outer diameter of the fixation plug may be substantially equal to, or slightly larger than, the diameter of the longitudinal hole formed in the suture anchor 110 . As such, in one or more embodiments, the fixation plug may be secured within, or engaged with, the suture anchor 110 , i.e., with the longitudinal hole of the suture anchor 110 , by disposing the fixation plug within the longitudinal hole of the suture anchor 110 . In one or more embodiments, frictional forces between the fixation plug and an inner surface of the longitudinal hole of the suture anchor 110 may engage with fixation plug within the longitudinal hole of the suture anchor 110 such that any sutures, e.g. the first suture 105 and the second suture 106 , that may be disposed through the eyelet may be secured within the suture anchor 110 . However, those having ordinary skill in the art will appreciate that a fixation plug may not be necessary in order to secure at least one suture within an eyelet of the suture anchor 110 . For example, in one or more embodiments, the eyelet may be formed near the distal end 112 of the suture anchor 110 , and the suture anchor 110 may be secured within a bone, e.g., the tibia 125 . As such, because the distal end 112 of the suture anchor 110 may be disposed within, and engaged with, the tibia 125 , the engagement between the outer surface of the suture anchor 110 and the hole formed in the tibia 125 , in which the suture anchor 110 is disposed, may secure at least one suture, e.g., the first suture 105 and the second suture 106 , within the eyelet of the suture anchor 110 .
Examples and further description of suture anchors and fixation plugs may be disclosed in co-pending U.S. application Ser. No. 12/259,106, titled “Anchor Assembly” and assigned to the assignee of the present disclosure, and hereby incorporated by reference in its entirety.
FIG. 2 shows one example of an anchor assembly 10 . The assembly 10 includes the anchor 20 and the insertion member 30 . The anchor 20 includes a proximal portion 21 , a distal portion 22 , and an inner cavity 23 . An opening 24 to the cavity 23 is located at the proximal portion 21 of the anchor 20 . A transverse through hole 25 is located between the proximal and distal portions 21 , 22 and extends through the anchor 20 . Openings 25 a,b are located at each end of the through hole 25 Located below each opening 25 a,b is a protrusion 26 . The protrusions 26 facilitate loading of a flexible member, such as a suture, through the through hole 25 , and allow for the creation of a path in the wall of a bone hole when the anchor 20 is inserted into bone hole. The outer surface 27 of the proximal portion 21 also includes barbs 28 for substantially reducing the possibility of removal of the anchor 20 when inserted into bone. The outer surface 27 also includes slots 29 extending from the openings 25 a,b of the through hole 25 to the proximal portion 21 of the anchor 20 . The slots 29 intersect the barbs 28 and are configured for housing of the suture after positioning of the anchor 20 in bone. The cavity 23 extends into the through hole 25 and includes a proximal portion 23 a and a threaded distal portion 23 b for receipt of a fixation plug 30 .
The fixation plug 30 includes a body 31 , having a proximal end portion 31 a and a flat distal end portion 31 b , and a head 32 coupled to the proximal end portion 31 a . The head 32 is configured for engagement with a delivery tool and the body 31 includes threads 31 c that are configured for engagement with the threads 23 c of the cavity 23 when the insertion member is arranged within the cavity 23 .
A method for meniscal repair, according to embodiments disclosed herein, may include providing a first tissue fixation member configured to secure a meniscal tissue, a suture anchor having an eyelet, and a first suture, securing the first suture to the first tissue fixation member. The method may also include making a single incision into a skin and forming a portal into a body and forming a hole within the bone, and engaging the first tissue fixation member and a delivery device and disposing the delivery device and the first tissue fixation member through the portal, into the body. Further, in one or more aspects, the method may also include engaging the second tissue fixation member and the delivery device and disposing the delivery device and the second tissue fixation member through the portal, into the body.
For example, referring to FIG. 1A , the first tissue fixation member 101 and the second tissue fixation member 102 are configured to secure the meniscal tissue 130 . As shown, each of the first tissue fixation member 101 and the second tissue fixation member 102 were delivered through the meniscal tissue 130 with a delivery device 109 . In one or more embodiments, each of the first tissue fixation member 101 and the second tissue fixation member 102 may be secured to, or engaged with, the delivery device 109 . In one or more embodiments, the delivery device 109 may include a cannulated spinal needle and an obturator (not shown), e.g., a deployment rod (not shown). Further, in one or more embodiments, the delivery device 109 may be formed from any substantially rigid or from a flexible, biocompatible material known in the art. For example, the cannulated spinal needle of the delivery device 109 may be formed from biocompatible plastics, polymers, metals, and any combination thereof. In one or more embodiments, the cannulated spinal needle may be a 17 gauge spinal needle. However, those having ordinary skill in the art will appreciate that the cannulated spinal needle may not necessarily need to be a 17 gauge spinal needle.
Still referring to FIG. 1A , as discussed above, each of the first tissue fixation member 101 and the second tissue fixation member 102 may include holes, or notches, formed therethrough, through which each of the first suture 105 and the second suture 106 may be engaged with, or coupled to, the first tissue fixation member 101 and the second tissue fixation member 102 , respectively. As such, according to one or more aspects, once the first suture 105 and the second suture 106 have been coupled to the first tissue fixation member 101 and the second tissue fixation member 102 , respectively, each of the first tissue fixation member 101 and the second tissue fixation member 102 may be disposed within the delivery device 109 , e.g., within the cannulated spinal needle (not shown).
Once a single incision into a skin, forming a portal (not shown) into a body, each of the first tissue fixation member 101 and the second tissue fixation member 102 may be disposed through the portal into the body with the delivery device 109 . According to one or more aspects, each of the first tissue fixation member 101 and the second tissue fixation member 102 may be engaged with, or secured to, the delivery device by disposing each of the first tissue fixation member 101 and the second tissue fixation member 102 within the delivery device. In one or more embodiments, an inner diameter of the cannulated spinal needle may be slightly larger than a diameter of the tissue fixation members 101 , 102 . As such, according to one or more aspects, each of the first tissue fixation member 101 and the second tissue fixation member 102 may be disposed within, and received by, the cannulated spinal needle of the delivery device 109 . Further, a distal end of the cannulated spinal needle may be angled, such that the distal end of the cannulated spinal needle is configured to pierce the meniscal tissue 130 .
According to one or more aspects, the cannulated spinal needle of the delivery device 109 may be inserted through the portal, into the body, and may pierce through the meniscal tissue 130 . Once the cannulated spinal needle of the delivery device 109 has pierced the meniscal tissue 130 , the obturator may be disposed within the cannula of the cannulated spinal needle from a distal end of the cannulated spinal needle, and may force, or push, at least one of the first tissue fixation member 101 and the second tissue fixation member 102 out of the cannulated spinal needle, i.e., deploy at least one of the first tissue fixation member 101 and the second tissue fixation member 102 from the delivery device 109 . Upon deployment of at least one of the first tissue fixation member 101 and the second tissue fixation member 102 , the first tissue fixation member 101 and the second tissue fixation member 102 may be reoriented such that a longitudinal axis of the first tissue fixation member 101 and the second tissue fixation member 102 may be substantially parallel to a contacting surface of the meniscal tissue 130 . In other words, upon deployment of the first tissue fixation member 101 and the second tissue fixation member 102 from the delivery device 109 , the first tissue fixation member 101 and the second tissue fixation member 102 may be reoriented to prevent the first tissue fixation member 101 and the second tissue fixation member 102 from being displaced through the hole formed in the meniscal tissue 130 from the piercing of the cannulated spinal needle of the delivery device through the meniscal tissue 130 .
The method may also include securing the first tissue fixation member to a meniscal tissue, threading the first suture through the eyelet of the suture anchor, securing the suture anchor within a bone, and tensioning the first suture within the suture anchor. The method may also include securing a second suture to a second tissue fixation member, threading the second suture through the eyelet of the suture anchor, and tensioning the second suture within the suture anchor.
For example, referring to FIG. 1B , each of the first tissue fixation member 101 and the second tissue fixation member 102 are secured to, or are engaged with, the meniscal tissue 130 . Further, as shown in FIG. 1B , each of the first suture 105 and the second suture 106 , which are coupled to the first tissue fixation member 101 and the second tissue fixation member 102 , respectively, may be threaded, or disposed, through the eyelet (not shown) of the suture anchor 110 .
As shown in FIG. 1C , the suture anchor 110 may be secured within the bone, e.g., within the tibia 125 . Further, each of the first suture 105 and the second suture 106 may be tensioned within the suture anchor 110 such that the area of the meniscal tissue 130 that is in contact with each of the first tissue fixation member 101 and the second tissue fixation member 102 may be pulled toward the suture anchor 110 , i.e., toward the tibia 125 . As discussed above, once each of the first suture 105 and the second suture 106 are tensioned, a fixation plug (not shown) may be engaged with the suture anchor to secure any sutures disposed through the eyelet of the suture anchor 110 within the suture anchor 110 . Furthermore, as discussed above, in one or more embodiments, three, four, five, or more tissue fixation members, that may be substantially identical to the first tissue fixation member 101 and the second tissue fixation member 102 , may be used in the assembly 100 to assist with securing the meniscal tissue 130 . For example, as shown in FIG. 1C , a third tissue fixation member 103 may be used in the assembly 100 to assist with securing the meniscal tissue 130 to the tibia 125 . As shown, the third tissue fixation member 103 is coupled to a third suture 107 , which is also disposed through the eyelet of the suture anchor 110 and is secured within the suture anchor 110 .
The method may also include disengaging the first tissue fixation member from the delivery device and removing the delivery device from the body, and disengaging the second tissue fixation member from the delivery device and removing the delivery device from the body. For example, once all of the fixation members, e.g., the first tissue fixation member 101 , the second tissue fixation member 102 , and the third fixation member 103 , are deployed from the delivery device 109 , the delivery device 109 may be removed from the body, through the portal described above.
According to one or more aspects, the methods described herein may also be used for other surgical procedures pertaining to the meniscus. For example, according to one or more aspects, the methods described herein may be used to secure, specifically, the anterior horn of a meniscus tear. Further, according to one or more aspects, the methods described herein may be used for a meniscal transplant procedure.
A kit for meniscal repair, according to embodiments disclosed herein, may include at least one tissue fixation member configured to secure a meniscal tissue, a suture anchor comprising an eyelet, at least one suture configured to be coupled to the at least one tissue fixation member and configured to be received through the eyelet of the suture anchor, and a delivery device configured to assist with delivery of the at least one tissue fixation member into a body.
For example, in one or more embodiments, the kit for meniscal repair may include at least one of the first tissue fixation member 101 , the second tissue fixation member 102 , and the third tissue fixation member 103 , the suture anchor 110 , and at least one suture configured to be coupled to the at least one tissue fixation member and configured to be received through the eyelet of the suture anchor, e.g., sutures 105 , 106 , 107 . Further, in one or more embodiments, the kit for meniscal repair may include the delivery device 109 configured to assist with delivery of the at least one tissue fixation member into a body. As discussed above, the delivery device 109 may include a cannulated spinal needle and an obturator (not shown), e.g., a deployment rod (not shown), configured to assist with deployment of the tissue fixation members.
Advantageously, embodiments disclosed herein may provide an assembly for meniscal repair that reduces the difficulties and time to repair the meniscus. The aspects of the invention, discussed above, may allow endoscopic meniscal repair to virtually any area of the meniscus and may minimize the danger to neurovascular structures and the need for additional ancillary incisions.
While embodiments have been described with respect to a limited number of embodiments, those skilled in the art, having benefit of this disclosure, will appreciate that other embodiments can be devised which do not depart from the scope of embodiments disclosed herein. Accordingly, the scope of embodiments disclosed herein should be limited only by the attached claims. | An assembly and method for reattaching tissue to bone from which the tissue had detached including a tissue fixation member will with a narrow cross section and a suture securely attached to the fixation member, the fixation member being configured to secure the detached tissue, a suture anchor fixable in bone at the region of reattachment, the anchor having an eyelet, the anchor including a textured outer surface, the suture having a free end passable through the eyelet to enable the detached tissue to be drawn into engagement with the bone at the region of reattachment. | 0 |
REFERENCE TO RELATED APPLICATION
[0001] This application claims priority to U.S. application Ser. No. 60/743,548, filed Mar. 17, 2006, the content of which is incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The invention relates generally to a waste collection system. More particularly, the invention relates to a combination dumpster and portable toilet.
BACKGROUND OF THE INVENTION
[0003] When performing various construction projects, it is necessary to remove rubbish that is generated during the construction project. One typical way of collecting and removing rubbish is using an elongated dumpster having an open top.
[0004] The dumpster is delivered to the area where the construction project is being done on a truck. The dumpster is then rolled off the truck and placed on the ground. Once the dumpster is filled with rubbish, the dumpster is rolled onto the truck and taken away for disposal.
[0005] When performing construction projects, it is typically not possible to use the plumbing facilities. As it is often necessary for workers to use a toilet while working, portable toilets are often delivered to the work site.
SUMMARY OF THE INVENTION
[0006] Various embodiments of the invention provide a housing for stowage of portable toilets that is integral to a dumpster unit. The arrangement provides for ready transportation of the portable toilets, protects the toilets from falling debris at a worksite, and provides a means for securing the toilets from theft or vandalism when the worksite is unattended.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 is a perspective view of a dumpster and portable toilet system according to an embodiment of the invention.
[0008] FIG. 2 is another perspective view of the dumpster and portable toilet system.
[0009] FIG. 3 is a bottom perspective view of the dumpster and portable toilet system.
[0010] FIG. 4 is a front view of the dumpster and portable toilet system.
[0011] FIG. 5 is a side view of the dumpster and portable toilet system.
[0012] FIG. 6 is an exploded perspective view of the dumpster and portable toilet system.
[0013] FIG. 7 is a side view of construction site maintenance system according to an embodiment of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0014] An embodiment of the invention is directed to a dumpster and portable toilet system, as illustrated at 10 in the figures. The dumpster and portable toilet system 10 generally includes a dumpster portion 20 and a toilet housing portion 30 .
[0015] In some configurations, the dumpster portion 20 has a capacity of about 10 yards, 20 yards or 30 yards. The dumpster portion 20 includes side panels 40 , a bottom panel 50 , a free end panel 60 , and a common end panel 70 , framed on the upper edges 80 , on the bottom by a chassis 90 , and on the four corners 100 , 110 , 120 and 130 . The common end panel 70 is so named because it forms a common wall between the dumpster portion 20 and the toilet housing portion 30 .
[0016] The free end panel 60 may be supported by a separate frame work 62 and mounted on hinges 64 to allow the panel to swing away from the end of the dumpster portion 20 to facilitate loading and unloading.
[0017] The toilet housing portion 30 is bounded by a top panel 140 , a bottom panel 150 , the aforementioned common end panel 70 and a side panel 160 , with ends 180 and 190 remaining open for toilet access. The panels of the toilet housing portion 30 are held together with an upper framework 200 , a lower framework 210 , corner posts 212 and 214 , and the corners 120 and 130 that support the common end panel 70 . The common end panel 70 is also supported and reinforced by a cross member 220 that extends between corners 120 and 130 , and a center post 230 . Alternatively, the toilet housing portion 30 may be fabricated without the panels covering the framework.
[0018] A support structure 240 depends from cross member 220 and the center post 230 to give the toilet housing 30 rigidity. The support structure 240 spans the interior of the toilet housing and is connected to a cross member 250 . The support structure also serves to divide the toilet housing portion 30 effectively into two compartments.
[0019] In another embodiment (not shown), the ends 180 and 190 could be enclosed, with side 160 being left open for toilet access. Such an arrangement would require substitution of the cross member 250 with a vertical post (not shown) that extends from the chassis 90 to an upper member of the framework 200 .
[0020] The chassis 90 is common to both the dumpster portion 20 and the toilet housing portion 30 . The dumpster and portable toilet system 10 may be equipped with rollers or casters 260 to aid in the positioning and movement of the dumpster and portable toilet system 10 .
[0021] Portable toilets contained within the toilet housing portion 30 can be secured by locking a chain around the toilet housing portion 30 , thereby preventing their removal from the toilet housing. Alternatively, the toilet housing portion 30 can be equipped with lock bars (not shown) that span the ends 180 and 190 and are detachably locked to the toilet housing portion 30 .
[0022] As an alternative to forming the portable toilet separate from the other components of the dumpster and portable toilet system 10 , it is possible that the portable toilet may be integrally fabricated as part of the dumpster and portable toilet system 10 .
[0023] The invention is also directed to a construction site maintenance system 300 that includes a transportation vehicle 302 on which the dumpster and portable toilet system 10 may be removably placed, as illustrated in FIG. 7 . In one configuration, the transportation vehicle 302 may be a conventional truck. Alternatively, the transportation vehicle 302 may be a trailer.
[0024] The dumpster and portable toilet system 10 may be placed onto and removed from the transportation vehicle 302 using a sliding motion with a hoist mechanism 304 . There are a variety of hoist mechanisms 304 for placing the dumpster and portable toilet system 10 onto the transportation vehicle 302 such as a cable and a hook.
[0025] The transportation vehicle 302 may also include equipment to service the portable toilet such as a fresh liquid tank 306 , a waste storage tank 308 , a fresh liquid pump system to deliver fresh liquid to the portable toilet and a waste pump system to remove waste from the portable toilet.
[0026] Alternatively, fresh liquid may be placed in the portable toilet before delivery of the dumpster and portable toilet system to the use location and waste can be removed from the portable toilet after the dumpster and portable toilet system is retrieved from the use location. In this configuration, a lid or sealing device may be provided in the portable toilet to prevent fresh liquid and waste from spilling from the portable toilet as the dumpster and portable toilet system is being placed onto and removed from the transportation vehicle 302 as well as while the transportation vehicle is moving to the use location.
[0027] In operation, the dumpster and portable toilet system 10 is placed on the transportation vehicle 302 and delivered to the use location. While it is possible to place the portable toilet in the dumpster and portable toilet system 10 after delivery to the use location, the portable toilet is preferably placed in the dumpster and portable toilet system 10 prior to delivery to the use location.
[0028] Once at the use location, the dumpster and portable toilet system 10 is moved off of the transportation vehicle 302 using the hoist mechanism 304 . The fresh liquid pump system is used to place fresh liquid in the portable toilet.
[0029] The dumpster and portable toilet system 10 is then used by placing refuse in the dumpster portion 20 and using the portable toilet for collection of bodily excrements such as urination and defecation. When done using the dumpster and portable toilet system 10 , the transportation vehicle 302 returns to the use location.
[0030] Prior to placing on the dumpster and portable toilet system 10 on the transportation vehicle 302 with the hoist mechanism 304 , the waste pump may be used to remove waste from the portable toilet. Alternatively, if the portable toilet needs service prior to filling of the dumpster portion 20 with refuse, the waster pump may be used for remove waste from the portable toilet and then the fresh liquid pump may be used to place fresh liquid into the portable toilet.
[0031] While the particular embodiments presented and described in detail above are exemplary of the invention, it is to be understood that they are merely illustrative. Various other modifications and changes with which the invention can be practiced and which are within the scope of the description provided herein will be readily apparent to those of ordinary skill in the art.
[0032] It is contemplated that features disclosed in this application, as well as those described in the above applications incorporated by reference, can be mixed and matched to suit particular circumstances. Various other modifications and changes will be apparent to those of ordinary skill. | A combination dumpster and portable toilet system is disclosed and described. The housing provides an enclosure for collection of refuse. The housing also provides for secure stowage of portable toilets to and from a worksite, as well as protection of the portable toilets from falling debris, theft and vandalism. | 4 |
This application is a continuation of application Ser. No. 156,483, filed Feb. 16, 1988, now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to image forming apparatus such as electrophotographic copying machines and laser beam printers, and more particularly to a control system for an image forming apparatus having a plurality of developing units, cassettes or other means.
2. Description of the Prior Art
Recently, image forming apparatus such as electrophotographic copying machines, laser beam printers and the like have been proposed wherein a plurality of paper feed cassettes are provided for accommodating copy paper of different sizes, a plurality of developing units are arranged around the surface of an electrostatic latent image bearing member in the direction of movement of the member, or copying operation can be conducted under a plurality of copy modes.
Further image forming apparatus generally have the automatic reset function of resetting all the copy modes to the initial standard state unless an input is given from the operation panel within a predetermined period of time after the completion of an image forming operation. The term "auto-reset" as used herein means the above-mentioned automatic reset function.
On the other hand, image forming apparatus have been proposed wherein a device or copy mode other than the device or mode currently in use for image forming operation can be specified by an advance input during the image forming operation. However, in the case where the next user fails to promptly make preparations and initiate the subsequent image forming operation, the auto-reset function is performed before the subsequent operation even if he entered copying conditions, different from the current conditions, in advance during the current image forming operation. Consequently, the advance input becomes useless.
This problem is encountered, for example, with apparatus wherein one of a plurality of developing units is selectively operated for development. Unexamined Japanese Patent Publication SHO No. 60-232566 discloses such an apparatus which is adapted to accept an advance input specifying a particular developing unit during the current image forming operation and to effect a change-over from the developing unit in use to the specified one immediately after the completion of the current operation. The disclosed apparatus has the advantage that the time required for using the developing unit, different from the one currently used, for the next image forming operation can be reduced only to the time required for the change-over, thereby improving the work efficiency.
Nevertheless, if the auto-reset means functions before the next user starts the next image forming operation despite the advance input, there arises the problem that the above-mentioned advantage can not be utilized.
SUMMARY OF THE INVENTION
The main object of the present invention is to provide an image forming apparatus wherein when an advance input is given by a user during image forming operation to specify a device, set value or mode different from the one in current use, the advance input is precluded from cancellation even if the user fails to promptly start the subsequent image forming operation.
Another object of the invention is to provide an image forming apparatus which is adapted to accept during image forming operation an advance input sepcifying a device, set value or mode different from the one currently in use so as to promptly initiate the subsequent image forming operation.
These and other objects of the invention can be fulfilled by providing an image forming apparatus including image exposure means for projecting a document image on the surface of an electrostatic latent image bearing member to form an electrostatic latent image on the surface, developing means for developing the latent image and transfer means for transferring the developed image onto a transfer material to obtain a copy image, the image forming apparatus comprising first image forming means for forming images in a first copy mode, second image forming means for forming images in a second copy mode different from the first copy mode, auto-reset means for returning the second copy mode to the first copy mode a predetermined period of time after the completion of image forming operation in the second copy mode, input means for entering a second copy mode specifying input during image forming operation in the first copy mode, and control means at least adapted to prohibit the auto-reset means from returning the second copy mode to the first copy mode or to delay the return of the mode when the second copy mode specifying input is entered during image forming operation in the first copy mode.
BRIEF DESCRIPTION OF THE DRAWINGS
In the following description, like parts are designated by like reference numbers throughout the several drawings.
FIG. 1 is a front view showing the overall construction of a copying machine;
FIG. 2 is a perspective view of a developing unit;
FIGS. 3 and 4 are sectional views showing the interior of the developing unit;
FIG. 5 is a perspective view of a shutter shift mechanism;
FIG. 6 is a plan view of an operation panel;
FIG. 7 is a control circuit diagram;
FIG. 8 is a flow chart showing the main routine for the copying machine;
FIG. 9 is a flow chart showing a developing unit change-over subroutine;
FIG. 10 is a flow chart showing an auto-reset subroutine;
FIG. 11 is a flow chart showing a modified auto-reset subroutine;
FIG. 12 is a plan view of an operation panel included in a second embodiment of the invention;
FIG. 13 is a flow chart showing the main routine for the second embodiment;
FIG. 14 is a flow chart showing a paper cassette change-over subroutine for the same;
FIG. 15 is a flow chart showing an auto-reset subroutine for the same; and
FIG. 16 is a flow chart showing a modification of the subroutine of FIG. 15.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
An image forming apparatus embodying the invention will be described below first with reference to FIGS. 1 to 11. The invention is embodied as an electrophotographic copying machine as will be described below. (Overall construction and operation of the copying machine, see FIG. 1)
With reference to FIG. 1, a photosensitive drum 2 disposed approximately in the center of a copying machine main body 1 is drivingly rotatable by an unillustrated main motor in the direction of arrow a. Arranged around the drum 2 are a sensitizing charger 3, inter-image eraser 4, first and second developing units 5, 6 of the magnetic brush type, transfer charger 7, separating charger 8, cleaner 9 and main eraser 10. These components are arranged in the order mentioned in the direction of rotation of the drum 2 at a specified spacing. An optical system 11 is disposed above the drum 2 and these components. A paper feed assembly 28 is provided at the left side of FIG. 1, and a fixing unit 26 at the right side thereof. At least three developing units may be provided.
The optical system 11 is of the slit exposure type including mirrors for scanning. The system 11 comprises a scanning unit 14 including a light source 12 and a first movable mirror 13, another scanning unit 15 including second and third movable mirrors 16, 17, a lens 18 and a fixed mirror 19. The surface of the drum 2 is charged by the charger 3, for example, to a positive polarity, while the eraser 4 removes the charge from the inter-image area of the drum 2, i.e., from the area thereof other than the image forming area corresponding to the document held between a document support glass table 20 and a document holder 21. While the scanning units 14, 15 are being moved by an unillustrated scanning motor in the direction of arrow b with the light surce 12 turned on, an electrostatic latent image corresponding to the document image is formed on the drum surface.
The scanning unit 14 is moved at a velocity of V/m wherein V is the peripheral speed of the drum 2, and m is the magnification. The scanning unit 15 is moved at a velocity of V/2m. When the scanning unit 14 is in its home position, the unit is in pressing contact with a home position switch 22, which in turn feeds a home position signal (which is "1" when the unit 14 is thus positioned) to the first CPU 200 to be described later. To operate the paper feed assembly 28 as timed with the scanning unit 14, the unit comes into pressing contact with a timing switch 23 upon traveling a predetermined distance in the direction b after the start of scanning, whereupon the switch 23 delivers to the first CPU unit 200 a timing signal (which becomes "1" upon the contact of the unit 14 with the switch 23) for operating the pair of timing rollers 24 to be described later.
A negatively charged toner is deposited on the surface of the drum 2 by the first or second developing unit 5 or 6 which is selected for use, whereby the latent image is developed to a visible toner image corresponding to the document image.
On the other hand, copy paper is sent out from the feed assembly 28 and is fed to the surface of the drum 2 by the pair of timing rollers 24 in response to the timing signal, whereupon the toner image is transferred to the paper by the corona discharge of the transfer charger 7. Immediately thereafter the paper is separated from the drum surface by virtue of removal of the charge by an alternating electric field set up by the separating charger 8 and owing to the stiffness of the paper itself. The copy paper separated from the drum 2 is fed by a conveyor belt 25 to the fixing unit 26, has the toner image thermally fixed thereto and is delivered onto a tray 27.
The toner remaining on the drum surface is removed by the cleaner 9, and the residual charge on the drum surface is erased by the main eraser 10.
The paper feed assembly 28 has an openable manual feeder 39, a first paper cassette 29 and a second paper cassette 30. When inserted through the manual feeder 39, copy paper is transported to the timing roller pair 24 via a pair of manual feed rollers 31 and a pair of intermediate rollers 32. Sheets of copy paper within the first or second cassette 29 or 30 are sent out one by one by a first or second feed roller 33 or 34 and transported to the timing roller pair 24 via the intermediate roller pair 32.
The rollers 24, 31, 32, 33 and 34 are disconnectably coupled to a a drive system including the main motor, each by a clutch. When the clutch is engaged, the roller concerned is coupled to the drive system and driven by the motor.
Arranged in the vicinity of the cassettes 29, 30 are sensors 35, 36 for detecting the size of copy paper accommodated in the cassettes 29, 30, respectively, and empty cassette sensors 37, 38 for detecting the absence of paper in the cassettes 29, 30, respectively.
(Developing unit, see FIGS. 2 to 5).
The first developing unit 5 in the upper position is filled with a developer containing a monochromatic color toner, while the second developing unit 6 in the lower position is filled with a developer containing a black toner. When the developing unit selection key 124 or 125 to be described later is depressed, one of the developing units 5 and 6 is driven for producing monochromatic or back copy images. Furthermore, a plurality of units, which are different in color, are prepared each for use as the first developing unit 5. These units are interchangeable for use in the copying machine main body 1.
First with reference to FIG. 2, the appearance of the developing units 5, 6 and the identification of colors will be described. Although FIG. 2 shows the first developing unit 5 as an example, the second developing unit 6 has a similar construction, with each part thereof designated by the corresponding reference number in parentheses in FIG. 2.
The developing unit 5 (6) has attached to lengthwise one end thereof a bracket 51 (61), to which a toner replenishing bottle 52 (62) is removably attached. The toner within the bottle 52 (62) is supplied to a developing tank by unillustrated toner supply means in response to a toner supply signal. The bracket 51 (61) is provided with a sensor 53 (63) positioned close to the bottle 52 (62) for detecting the presence or absence of the bottle, and with a sensor 54 (64) positioned close to the toner supply opening for detecting the bottle when it becomes empty. The sensor 53 (63) remains on while the bottle 52 (62) is installed in place but is turned off when it is removed. The sensor 54 (64) remains on while the toner remains in the bottle 52 (62) but is turned off when it becomes empty.
Magents 55, 56 (65, 66) can be attached to the upper side of the developing unit 5 (6). Positioned in corresponding relation to the magnets are first and second reed switches 57, 58 (67, 68) attached to the main body 1. The on-off combinations of these reed switches make it possible to identify the colors of toners as listed below.
______________________________________lst Switch 57 (67) 2nd Switch 58 (68) Color of toner______________________________________ON ON BlackON OFF RedOFF ON YellowOFF OFF Blue______________________________________
The interior construction of the second developing unit 6 will now be described with reference to FIGS. 3 and 4. The first developing unit 5, which will not be described, has substantially the same interior construction as the second except that it does not have the shutter 73 to be described below.
The developing unit 6 has a developing sleeve 70 opposed to the photosensitive drum 2, and a magnet roller 71 housed in the sleeve 70 and having N and S seven poles along its outer periphery. The rear portion of the magnet roller 71 away from the drum 2 has no magnetism or a weak magnetic force. A bucket roller 74 and a screw roller 75 are arranged in the rear of the developing sleeve 70, with a shutter 73 interposed between the sleeve and the roller 74. The rollers 74, 75 are drivingly rotatable in the direction of arrows c, d, respectively. The developer is circulated by the rollers 74, 75, and the screw roller 75 is replenished with the toner from the bottle 62. The developer is passed over the shutter 73 in the direction of arrow e, supplied to the developing sleeve 70, transported in the direction of arrow f owing to the rotation of the sleeve 70 itself in the same direction while being attracted in the form of a brush to the outer peripheral sleeve surface and brought into rubbing contact with the drum surface at a developing station for development. The developer thereafter moves off the sleeve surface at the rear portion of the magnet roller 71 where the roller 71 has low or no magnetism, and is returned to the bucket roller 74 toward the direction of arrow g.
The present copying machine includes the developing units 5, 6 which are arranged side by side and one of which is selectively operable. When one of the developing units, especially the first developing unit 5, of such apparatus is selected for use in developing operation, the developer on the outer periphery of the sleeve 70 of the other developing unit 6 must be held out of contact with the surface of the drum 2 to obviate the undesired deposition of the toner and to preclude the developer of the second unit 6 in the lower position from disturbing the toner image formed by the first unit 5.
When the first developing unit 5 of the present embodiment is selected, therefore, the shutter 73 of the second unit 6 unnecessary for development is turned to an approximately vertical position as shown in FIG. 4, and the developing sleeve 70 is driven for a short period of time, whereby the developer from the bucket roller 74 is returned by the shutter 73 toward the direction of arrow e' without being supplied to the sleeve 70. The developer portion remaining on the sleeve surface is forced toward the direction of arrow g by the rotation of the sleeve and is collected by the bucket roller 74. Consequently, no developer remains on the surface of the sleeve 70, permitting the latent image or toner image to pass through the developing station of the second unit free of any adverse influence.
FIG. 5 shows a mechanism for shifting the shutter 73. The shifting mechanism comprises a lever 78 fixed to a pivot 77 for the shutter 73, a solenoid 79 with a plunger 79a connected to the lever 78, and a coiled spring 80 biasing the lever 78 in the direction of arrow h. Usually, the solenoid is held unenergized, and the lever 78 is biased toward the direction h by the spring 80 to position the shutter 73 approximately horizontally as shown in FIG. 3. When the first developing unit 5 is selected, the solenoid 79 is energized, with the sleeve 70 in rotation in the direction of arrow f, retracting the plunger 79a and turning the lever 78 in a direction opposite to the arrow h until the lever comes into contact with a stopper 81 to position the shutter 73 approximately vertically as seen in FIG. 4. Consequently, the developer is removed from the outer peripheral surface of the developing sleeve 70 as already described. Subsequently, the sleeve 70 is stopped, and the solenoid 79 is deenergized, returning the shutter 73 to the initial generally horizontal position. With the sleeve 70 held out of rotation, there is no likelihood that some developer will remain on the sleeve surface.
When the second developing unit 6 is selected, the developing sleeve 70 is driven as it is, whereby the developer is supplied as transported on the sleeve surface to the developing station.
According to the present embodiment, it is only the second developing unit 6 that is equipped with the means for bringing the developer away from the developing station by the shutter 73. The first developing unit 5 is so controlled as to alter the developing bias voltage to be applied to the developing sleeve instead of employing the shutter 73 for discontinuing the supply of the developer. To prevent fogging with toner, the developing bias voltage applied to the developing sleeve generally has a polarity opposite to the polarity of the charge on the toner. In this case a higher developing bias voltage is applied to the sleeve than when the first unit is selected. The toner is then effectively attracted to the developing sleeve without the likelihood of adhering to the latent image passing through the developing station. Since the second developing unit 6 uses the black toner in the case of the present embodiment, the first developing unit 5 which uses a monochromatic toner is merely so controlled as stated above, and yet black toner images can be obtained actually almost free of any adverse effect.
Further according to the present embodiment, the depression of the key 124 or 125 on a control panel 100 renders the developing unit 5 or 6 selectable, even during copying operation, for the subsequent copying When the selection is thus accepted, auto-resetting of the developing unit input is prohibited or delayed. Consequently, even if the next user fails to promptly make preparations for his copies, at least the time required for selecting the developing unit 5 or 6 can be saved. The control process for this purpose will be described in detail later with reference to the flow charts concerned.
(Operation panel, see FIG. 6)
The operation panel is provided on the top of the copying machine main body 1 and has a print key 102, interrupt key 103, display 104 for showing the number of copies to be made and trouble codes, clear/stop key 105 for discontinuing copying operation immediately after the start thereof or during multicopying operation (for making a plurality of copies continually from a document) and for returning the copy number indicated on the display 104 to the standard mode, i.e. "1", number entry keys 106 to 115 for setting the copy number on the display 104, exposure up key 116 and exposure down key 117 for giving an adjusted image density by increasing or decreasing the amount of exposure by the light source 12, LEDs 118 to be selectively turned on or indicating the amount of exposure (image density), paper size (paper feeder) selection key 119, LEDs 120 to 123 for indicating the selected paper size, developing unit selectio keys 124, 125 for selecting the first unit 5 or second unit 6, LEDs 126, 127 for indicating the selected unit 5 or 6, LEDs 128 to 131 for indicating the color of the toner in the selected unit 5 or 6, and LED 132 for representing the absence of toner in the toner replenishing bottle 52 or 62 on the selected developing unit 5 or 6.
(Constrol circuit, see FIG. 7)
The control circuit for the copying machine of the foregoing construction comprises the first CPU 200 which is the main component, and a second CPU 300 for controlling the optical system 11. Connecting to the first CPU 200 is a switch matrix 201 including various keys on the operation panel 100, tonner bottle sensors 53, 63, toner absence sensors 54, 64, reed switches 57, 58, 67, 68 for detecting the colors of toners, etc. which are arranged in rows and columns. In response to the depression of keys and operation of sensors, the first CPU 200 controls main motor 501, timing roller clutch 502, first feed roller clutch 503, second feed roller clutch 504, sensitizing charger 3, transfer charger 7, first developing motor 505, second developing motor 506, inter-image eraser 4, shutter solenoid 79, etc. Further the display 104 and the LEDs are on-off controlled by the first CPU via the matrix 201 and a decoder 133.
On the other hand, the second CPU 300 has connected thereto the home position switch 22, timing switch 23 and control circuits for the scanning motor and the lens 18 and is connected to the first CPU 200 for synchronized operation.
(Control process, see FIGS. 8 to 11)
FIG. 8 shows the main routine to be performed by the first CPU 200.
When the first CPU 200 is reset for starting the program, Step S1 is performed for initialization, clearing the random access memory, initializing various registers and setting component devices in the initial mode. An internal timer for determining the time required for the main routine is then started in Step S2. The time value is preset by the initialization of Step S1.
Subsequently, the subroutines are called in succession in steps S3 to S6, and after the completion of all the subroutines, the sequence returns to step S2 on completion of the operation of the internal timer. Using the time interval of one routine, various timers perform counting operation during the subroutine.
Step S3 is a change-over subroutine which is performed for the selected developing unit 5 or 6. Step S4 is the auto-reset subroutine to be performed after the completion of copying operation. These steps will be described in detail below. Step S5 is a copying operation setting subroutine which is performed in accordance with inputs from the operation panel 100. Step S6 is a subroutine for producing output signals for controlling various devices to conduct a copying operation. The subroutines of Steps S5 and S6 are known and therefore will not be described.
FIG. 9 shows the developing unit change-over subroutine to be executed in Step S3 of the main routine.
First, Step S10 inquires whether a developing unit selecting input has been given. When the answer is affirmative, Step S11 sets a flag A to "1", indicating that the selecting input has been entered. Step S12 then inquires if the machine is in copying operation. If the answer is affirmative, a flab B is set to "1" in Step S13. The flag B, when "1", indicates that the developing unit selecting input has been given during copying operation.
Next, Step S14 inquires whether the selected unit is the first developing unit 5. If the answer is affirmative, a flag F1 is set to "1" in Step S15, showing the unit 5 as selected. Step S19 then follows. If the second unit 6 is found selected, the inquiry of Step S14 is answered in the negative. A flag F2 is set to "1" in Step S16, indicating that the second unit 6 has been selected. The sequence then proceeds to Step S19.
On the other hand, if no developing unit is found to be selected in Step S10, Step S17 checks whether the flag A is "1". If it is "1", Step S19 directly follows. If otherwise, the flags F1 and F2 are reset to "0" in Step S18, followed by Step S19.
Step S19 checks whether the machine is currently in copying operation. When it is in operation, the sequence returns to the main routine. If otherwise, Steps S20 and S22 are performed to check whether the flags F1 and F2 are "1". When the flag F1 is found to be "1" in Step S20, Step S21 starts a change-over to the first unit 5. The flag A is reset to "0" in Step S24, whereby the subroutine is completed. If the flag F2 is found to be "1" in Step S22, Step S23 starts a changeover to the second unit 6, followed by Step S24 to complete the present subroutine.
FIG. 10 shows the auto-reset subroutine to be executed in Step S4 of the main routine.
When no input is given via the operation panel 100 after the completion of copying operation and until the completion of operation of an auto-reset timer, the copying machine is changed from the copy mode to the standard mode in this subroutine so as to obviate errors by the next user. The items to be auto-reset include the image density, magnification, copy number and developing unit settings. As to the developing unit, auto-resetting may be prohibited as an exceptional case.
Step S30 inquires whether the operation of the auto-reset timer is complete. When the answer is affirmative, Step S37 follows. If it is in the negative, Step S31 checks the auto-reset timer as to whether it is counting. Since the auto-reset timer is started in Step S34, the inquiries of Steps S30 and S31 are answered in the negative, and Step S32 checks whether the machine is in copying operation. If it is in operation, Step S40 follows. If otherwise, Step S33 checks whether an input is given via the operation panel 100. When the answer is affirmative, Step S40 follows. If otherwise, the auto-reset timer is started in Step S34. The sequence then proceeds to Step S40.
When the inquiry of Step S31 is answered in the affirmative with the auto-reset timer in counting operation, Step S35 inquires if there is an input from the operation panel 100. When the answer is negative, Step S40 follows. If it is affirmative, the auto-reset timer is stopped in Step S36, which is followed by Step S40.
On the other hand, if the auto-reset timer produces a completion signal in the absence of input, the inquiry of Step S30 is answered in the affirmative, followed by Step S37, which checks the flag B as to whether it is "1". As already stated, this flag B is set to "1" in Step S13 if a developing unit selecting signal input is given during copying operation. When the flag B is found to be "1", the copy mode except for the developing unit setting is returned to the standard mode in Step S39, followed by Step S40. In this way, despite the completion of auto-reset timer operation, auto-resetting of the developing unit selecting input accepted during copying operation is prohibited. On the other hand, if the flag B is "0", the copy mode is entirely returned to the standard mode in Step S38, and the sequence proceeds to Step S40.
Step S40 inquires whether the machine has been initiated into copying operation. If the answer is in the negative, the sequence returns to the main routine. When the machine is already in operation, the flag B is reset to "0" in Step S41. In Step S42, the auto-reset timer is reset to complete the subroutine.
FIG. 11 shows a modification of the auto-reset subroutine. The modified subroutine is the same as the subroutine of FIG. 10 except that Step S39 is followed by Steps S43 and S44.
When the machine is returned to the standard mode except for the developing unit setting in Step S39, with the unit selecting input given during copying operation, the flag B is reset to "0" in Step S43, and the auto-reset timer is reset in Step S44. Consequently, when no input is entered by the operation panel 100, the auto-reset timer is started again in Step S34. After a timer operation completion signal is given, the inquiry of Step S37 is answered in the negative. It is in Step S38 that the developing unit setting is auto-reset.
With the modified subroutine, therefore, the developing unit selecting input is auto-reset upon lapse of two times the time interval of the foregoing case.
The selection input auto-resetting may be delayed similarly using a different timer.
Although the developing unit only can be selected by an advance input according to the present embodiment, other modes, various elements, etc. of the image forming apparatus may be made selectable by advance inputs. A second embodiment will be described below wherein not only the developing unit but also the paper cassette is selectable by an advance input.
This embodiment, i.e. copying machine, is similar to the first embodiment in overall construction and operation, and in respect of the developing units.
FIG. 12 shows the operation panel of the second embodiment, which is the same as the one shown in FIG. 6 except that the paper size (feeder) selection key 119 and the paper size display LEDs 120 to 123 of the first embodiment are replaced by a paper feeder selection key 119A, and a first feed unit display LED 120A and a second feed unit display LED 121A for indicating the selected paper feeder.
The control process will be described next. FIG. 13 shows the main routine which is the same as the main routine (FIG. 8) of the first embodiment except the routine of FIG. 13 further includes Step S8 which is a subroutine for a change-over between the paper feed units 29 and 30 to use the selected one.
Step S3, a developing unit change-over subroutine, for the second embodiment is the same as the corresponding step shown in FIG. 9. The paper feed unit change-over subroutine to be performed in Step S8 is shown in FIG. 14.
First, Step S50' inquires whether a feed unit selecting input has been given. When the answer is affirmative, Step S51' sets a flag A' to "1", indicating that the selecting input has been entered. Step S52' then inquires whether the machine is in copying operation. If the answer is affirmative, a flag B' is set to "1" in Step S53'. This flag B', when "1", indicates that the feed unit selecting input has been given during copying operation.
Next, Step S54' inquires whether the selected unit is the first feed unit 29. If the answer is affirmative, a flag F1' is set to "1" in Step S55', indicating the unit 29 as selected. Step S59' then follows. If the second feed unit 30 is found selected, the inquiry of Step S54' is answered in the negative. A flag F2' is set to "1" in Step S56', indicating that the second unit 30 has been selected. The sequence then proceeds to Step S59'.
On the other hand, if no feed unit is found to be selected in Step S50', Step S57' checks whether the flag A' is "1". If it is "1", Step S59' directly follows. If otherwise, the flags F1' and F2' are reset to "0" in Step S58', followed by Step S59'.
Step S59' checks whether the machine is currently in copying operation. When it is in operation, the sequence returns to the main routine. If otherwise, Steps S60' and S62' are performed to check whether the flags F1' and F2' are "1". When the flag F1' is found to be "1" in Step S60', Step S61' starts a change-over to the first feed unit 29. The flag A' is reset to "0" in Step S64', whereby the subroutine is completed. If the flag F2' is found to be "1" in Step S62', Step S63' starts a change-over to the second unit 30, followed by Step S64'to complete the subroutine.
FIG. 15 shows the auto-reset subroutine to be performed in Step S4 of the main routine. This subroutine is similar to the subroutine of FIG. 10 with the exception of the following steps. Step S37 checks whether the flag B is "1". If it is "1", Step S100 checks whether the flag B' is "1". As already stated, when a feed unit selecting input is given during copying operation, this flag B' is set to "1" in Step S53'. When the flag is found to be "1", the copy mode is returned to the standard mode except for the developing unit setting and the feed unit setting in Step S101. The sequence the proceeds to Step S40.
When the inquiry of Step S100 is answered in the negative, the copy mode is returned to the standard mode except for the developing unit setting in Step S102, which is followed by Step S40.
When Step S37 finds that the flag B is not "1", Step S103 checks whether the flag B' is "1". If it is "1", the copy mode is returned to the standard mode except for the feed unit setting in Step S104. The sequence then returns to Step S40. If the answer to the inquiry of Step S103 is in the negative, the copy mode is entirely returned to the standard mode in Step S105.
FIG. 16 shows a modification of the auto-reset subroutine of the second embodiment. The modified subroutine is the same as the subroutine of FIG. 15 except that Steps S101, S102 and S104 are followed by Steps S106 and S107.
With a developing unit or feed unit selecting input accepted during copying operation, Step S101 returns the copy mode to the standard mode except for the developing unit setting and the feed unit setting, or Step S102 returns the copy mode to the standard mode except for the developing unit setting, or Step S104 returns the copy mode to the standard mode except for the feed unit setting, the flag B and/or B' is then reset to "0" in Step S106. and the auto-reset timer is reset in Step S107. Consequently, when no input is entered by the operation panel 100, the auto-reset timer is started again in Step S34. After a timer operation completion signal is given, the inquiry of Step S37 is answered in the negative. It is in Step S105 that the developing unit or feed unit setting is auto-reset.
With the modified subroutine, therefore, the developing unit or feed unit selecting input is autoreset upon lapse of two times the time interval of the foregoing case.
Futhermore, the present invention can be embodied for the selection of the paper feeder in advance. For example, during copying operation with use of the first feeder 29, the next user specifies the second feeder 30 with an advance input by depressing the feeder selection key 119A on the operation panel of FIG. 12. In this case, the auto-resetting of the advance input for the second feeder is prohibited or delayed.
The above feeder selection is executed according to the subroutine of FIG. 14. Further the flag B' is checked as to whether it is "1" in Step S37 of FIGS. 10 or 11, and depending on the state of the flag, Step S39 returns the copy mode to the standard mode except for the feed unit setting, whereby the auto-resetting of the feed unit setting is prohibited or delayed.
The present invention can be embodied similarly for setting the magnification, the number of copies, etc. The desired value may be specified by an advance input for only one of these items as in the first embodiment or for more than one of these items as in the case of the second embodiment.
Although the present invention has been fully described by way of examples with reference to the accompanying drawings, it is to be noted that various changes and modifications will be apparent to those skilled in the art. Therefore, unless otherwise such changes and modifications depart from the scope of the present invention, they should be construed as being included therein. | The disclosure relates to an image forming apparatus capable of executing a copying operation by combining a plurality of copying conditions inclusive of at least a standard condition and a condition different from the standard condition. In the image forming apparatus, the designated condition is automatically returned to the standard condition after a lapse of predetermined time after the copying operation, but when any one of conditions different from the standard condition is entered during the copying operation, the entered condition is prohibited from being automatically returned to the standard condition or the predetermined time for automatically returning the designated condition to the standard condition is extended. | 6 |
FIELD OF THE INVENTION
The present invention relates generally to communication systems, and more particularly to gathering context information about a communication from a user who generated the communication in a communication system.
BACKGROUND
The use of communication channels of many types has increased greatly, given the recent proliferation of communication technologies. Similarly, the use of social, business, and personal networking services has also increased greatly. Communication channels in widespread use include, for example, telephone voice channels, cellular phone text message channels, computerized instant messaging channels, electronic mail channels, and so on. It is often the case that a given person is able to use a given communication channel in multiple ways. For example, a given person may have a business phone number and a cell phone number, or may have multiple email addresses. It is often the case that one person wants to communicate with another immediately or very soon, to give or receive information or to otherwise collaborate in a timely fashion. Channels that enable such communications can be referred to as real-time communication channels. Typically, one person will attempt to contact another using a real time communication channel, and the person being contacted can decide whether to respond. As communication services and technology evolve, the number of alternate communication channels that people use to contact each other grows. Additionally, the number of social, business, and personal networking services also grows. As such, the burden of monitoring and managing all of the possible communication channels and social, business, and personal networking services, with their attendant devices and interfaces, grows ever greater.
Several current solutions attempt to coordinate the many alternate communication channels and the social, business, and personal networking services to alleviate the burden of monitoring and managing the coordinated channels and services. For example, unified communications solutions involve the integration of real-time communication services such as instant messaging, presence information, telephony, and video conferencing with non-real-time communication services such as unified messaging (integrated voicemail, email, text messaging, and fax). Unified communications solutions typically involve multiple products that attempt to provide a unified user interface and user experience. Unified communications solutions can allow a person to send a message on one medium and for it to be received on another medium. For example, a person can receive a voicemail message and choose to access it through e-mail or a cell phone. If the sender of the voicemail message is online, according to the sender's presence information, and available to currently accept calls, the response to the voicemail can be sent immediately through text chat or video call. Alternatively, it may be sent as a non real-time message that can be accessed through a variety of media. Unfortunately, no current solution adequately alleviates the burden of monitoring and managing multiple coordinated channels and services.
SUMMARY
Embodiments of the present invention provide for a program product, system, and method for receiving a first information related to a communication sent to a user device of a second person, determining a user device of a first person using the first information, sending a context information request to the user device of the first person, receiving a context information reply responsive to the context information request, sending context information of the context information reply to the user device of the second person, and releasing the communication to the user device of the second person.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
FIG. 1 is a functional block diagram of communications system 100 in accordance with an embodiment of the present invention.
FIG. 2 is a diagram of communications and other messages being made in communications system 100 in accordance with an embodiment of the present invention.
FIG. 3 is a flowchart depicting the steps followed by server 120 in accordance with an embodiment of the present invention.
FIG. 4 is a block diagram of hardware and software within communications system 100 in accordance with an embodiment of the present invention.
DETAILED DESCRIPTION
FIG. 1 depicts a functional block diagram of communications system 100 in accordance with an illustrative embodiment of the present invention. Communications system 100 includes network 110 , server 120 , user device 130 , user device 132 , and user device 140 . Network 110 can be, for example, a local area network (LAN), a wide area network (WAN) such as the Internet, or a combination of the two, and can include wireline or wireless connections. In general, network 110 can be any combination of connections and protocols that will support communications via various channels between server 120 , user device 130 , user device 132 , and user device 140 in accordance with an embodiment of the invention. Persons 102 and 104 can use communications system 100 to communicate with each other via various channels as described below.
In various embodiments, server 120 can include a laptop, tablet, or netbook personal computer (PC), a desktop computer, a personal digital assistant (PDA), a smart phone, a mainframe computer, or a networked server computer. Further, server 120 can represent computing systems utilizing clustered computers and components to act as single pools of seamless resources when accessed through network 110 , or can represent one or more cloud computing datacenters. In general, server 120 can be any programmable electronic device as described in further detail with respect to FIG. 4 .
User device 130 , user device 132 , and user device 140 can include in various embodiments a cellular phone, a conference phone, a speaker phone, a desk set, a computer with a resident software phone, or any other type of communication device that can exchange voice signals, exchange and process data, or both. User device 130 , user device 132 , and user device 140 are each able to transmit and receive voice signals, data signals, or both to and from each other, to and from server 120 , or both. In general, user device 130 , user device 132 , and user device 140 can be any programmable electronic device as described in further detail with respect to FIG. 4 .
Server 120 includes context program 122 . Context program 122 can operate to intercept a communication from user device 130 of person 102 to user device 140 of person 104 , retrieve context information from person 102 via user device 130 or user device 132 , and provide person 104 with the context information via user device 140 . In one embodiment, the context information is acquired in a consistent manner to give person 104 a predictable context regarding the nature of the communication, which enables person 104 to better decide how and when to respond. In one embodiment, context program 122 does this by giving person 102 a way to furnish certain useful information before person 104 is contacted. Context program 122 acquires this context information regardless of the particular communication device person 102 is using. In one embodiment, if user device 130 lacks an ability to retrieve context information from person 102 , then context program 122 can engage person 102 at a second device, such as user device 132 , so that by the time person 104 is aware of the communication, person 104 has the information necessary to decide in real time how and when to respond. A communication from person 102 to person 104 , as well as a retrieval and provision of context information, are discussed below with reference to FIG. 2 .
FIG. 2 depicts communication 260 between person 102 and person 104 , as well as redirection message 262 , context information request 264 , context information reply 266 , and context information message 268 , in accordance with an illustrative embodiment of the present invention. Communication 260 is depicted in FIG. 2 as a message transmitted from user device 130 to user device 140 . In one embodiment, communication 260 can be an account message transmitted from user device 130 to user device 140 , initiated by person 102 composing an email message on user device 130 and sending the email message to user device 140 via an email server (not pictured). In another embodiment, the account message is a social networking account message, sent via a social networking server (not pictured). In both embodiments, the email server or social networking server can receive the account message and store it in association with an account of person 104 , and thereinafter send the account message to user device 140 upon retrieval. In another embodiment, communication 260 is an SMS message transmitted from user device 130 to user device 140 , initiated by person 102 sending person 104 an SMS message by composing the SMS message on user device 130 and sending it to user device 140 substantially directly. In yet another embodiment, communication 260 is a phone call transmitted from user device 130 to user device 140 , initiated by person 102 dialing a phone number associated with user device 140 . In various embodiments communication 260 can be any kind of communication.
As discussed above, user device 130 transmits communication 260 . In various embodiments, each distinct account (e.g., an email account, social networking account, or another account used for communication) can be regarded as a channel used by user device 130 for making communication 260 . Each distinct phone number (e.g., the phone number of user device 130 , user device 140 , or another phone number used for communication) can be regarded as a channel used by user device 130 for making communication 260 . Further, any distinct mode of communication or distinction made to distinguish a communication endpoint can be regarded as a channel used by user device 130 for making communication 260 .
In one embodiment, communication 260 includes full message content. For example, communication 260 can include an entire email message, an entire social networking account message, or an entire SMS message. In another embodiment, communication 260 does not include full message content, and instead includes a notification that full message content is available elsewhere. For example, communication 260 can include a notification that an entire email message, an entire social networking account message, or entire SMS message is available for retrieval on an appropriate server. In an embodiment in which communication 260 is a phone call, communication 260 typically will not include any message content, and instead will include a notification that user device 130 is available to open a voice connection, for example.
In one embodiment, context program 122 of server 120 intercepts communication 260 before person 104 is made aware of communication 260 . Thus, although in FIG. 2 communication 260 is depicted as reaching user device 140 , it should be understood that communication 260 can be intercepted. Context program 122 can intercept communication 260 in several ways. For example, in one embodiment, person 104 can register user device 140 with server 120 , so that communication 260 is redirected from user device 140 to server 120 . In another embodiment, person 104 can establish a communication account on server 120 and instruct all callers to send communication 260 directly to server 120 . In yet another embodiment, person 102 can register user device 130 with server 120 , so that communication 260 is redirected from user device 130 to server 120 without initially being transmitted to user device 140 . In one embodiment, communication 260 is intercepted and redirected from user device 140 via redirection message 262 , which transfers communication 260 , or salient information about communication 260 , to context program 122 of server 120 .
After intercepting communication 260 and receiving redirection message 262 , context program 122 transmits context information request 264 to person 102 via either user device 130 , or a second device, such as user device 132 , as depicted in FIG. 2 . Context program 122 will select either user device 132 or user device 130 depending on which one has a suitable interface with which to retrieve context information from person 102 . Having received redirection message 262 , context program 122 determines that communication 260 was sent directly from user device 130 , and also determines that person 102 is additionally reachable via user device 132 by referral to, for example, a table listing all user devices usable to reach a given person. If user device 130 and user device 132 both have a suitable interface, then in one embodiment context program 122 chooses user device 130 from which communication 260 originated, because it is more likely that person 102 will already be paying attention to user device 130 . Upon receiving context information request 264 , the receiving user device, for example user device 132 , surfaces an interface suitable for gathering context information from person 102 . To surface an interface, a user device presents the interface to a person using a suitable medium, or prompts the person to respond to the interface. In one embodiment, user device 132 may not be equipped to surface a visual interface, but may be equipped for surfacing an audio interface. Alternately, user device 132 may be equipped to surface a visual interface, but may not be equipped for surfacing an audio interface.
Having received context information request 264 , in one embodiment user device 132 surfaces a visual interface with labels or text prompts instructing person 102 to enter context information, including one or more of the subject of communication 260 , a description of communication 260 , the urgency of communication 260 , a deadline of contact for communication 260 , and other context information. In one embodiment, user device 132 can surface a voice or video interface with voice prompts or video prompts instructing person 102 to enter context information including one or more of the items described above.
After gathering the context information utilizing the surfaced interface, user device 132 transmits the context information in context information reply 266 to context program 122 of server 120 . If the context information is inadequate by virtue of missing requested information, then in one embodiment context program 122 can resend context information request 264 and require the missing context information before sending context information message 268 to user device 140 . For example, the name of person 102 , or other mandatory information, if omitted, might be required. Further, if the context information is inadequate by virtue of needing additional information context program 122 can resend context information request 264 and require additional context information before sending context information message 268 to user device 140 . For example, if half of a set of optional information questions are unanswered, a new set of questions might be required to be answered. The required additional context information can be new or different information not requested in the original request, while the required missing context information can be information that was requested in the original request. In one embodiment, user device 132 can send the context information directly to user device 140 .
After receiving context information reply 266 , context program 122 transmits the context information in context information message 268 to user device 140 . If certain context information has been omitted by person 102 , then in one embodiment person 104 instructs context program 122 to resend context information request 264 and require the missing context information.
When user device 140 receives context information message 268 , person 104 has a consistent and predictable way to assess communication 260 , either as an isolated communication or in comparison to other communications, and thus has an ability to determine how and when to respond. For example, if communication 260 is from a stranger, it will often be ignored by person 104 , but if person 104 receives communication 260 in combination with context information message 268 , the additional context information in context information message 268 about subject, urgency, or other topics helps distinguish communication 260 in a way that may spur person 104 to give communication 260 attention sooner, if not immediately. For another example, if communication 260 is from a colleague of person 104 it may be answered immediately out of courtesy, when it is the case that an immediate response is not necessary or requested by person 102 , but if person 104 receives communication 260 in combination with context information message 268 , person 102 might realize that answering communication 260 is not necessary or requested.
In various embodiments, context information message 268 can be presented to person 104 in several ways, depending on the channel and device types of user device 140 , user device 130 , and user device 132 . In one embodiment, for example, although communication 260 is a phone call and context information was gathered by surfacing an audio interface on user device 130 , context information message 268 can be presented on user device 140 as text or video, via a speech-to-text component of server 120 . In another embodiment, in which communication 260 is an SMS message and context information was gathered by surfacing a text interface on user device 132 , context information message 268 can be presented on user device 140 as audio, via a text-to-speech component of server 120 . In yet another embodiment, context information message 268 can be presented on user device 140 in a form substantially similar to the form in which it was gathered on user device 130 or user device 132 .
In various embodiments, context information message 268 can be analyzed and additionally interpreted for the caller, to contextualize the degree of urgency. For example, if context information message 268 indicates that communication 260 is urgent, context program 122 can contextualize the urgency by correlating context information message 268 with a fact, supplied by person 104 , that person 102 is typically excitable or tends to exaggerate the degree of urgency of his or her messages. In another embodiment, context program 122 or user device 140 can accumulate context information message 268 along with additional context information messages, to compile profiles of callers, for example. Further, unanswered communication, including communication 260 , can be gathered into a list within context program 122 or on user device 140 , allowing person 104 or an agent of person 104 to compare communications for the purpose of processing them most efficiently. Further still, communication histories can be used to document and recall responses and analyzed to provide deeper knowledge about response patterns and behaviors.
FIG. 3 includes flowchart 300 depicting the steps followed by server 120 in accordance with an embodiment of the present invention. In step 310 , context program 122 of server 120 intercepts a communication by receiving a redirection message. For example, in one embodiment context program 122 can intercept communication 260 by receiving redirection message 262 from user device 140 . In another embodiment, context program 122 can intercept communication 260 by receiving redirection message 262 directly from user device 130 . In step 312 , context program 122 determines if the user device that sent the communication has a suitable interface. For example, context program 122 can determine if user device 130 has a suitable interface for surfacing a particular kind of interface. If context program 122 determines that the sending user device has a suitable interface, flowchart 300 proceeds to step 316 . If context program 122 determines that the sending user device does not have a suitable interface, flowchart 300 proceeds to step 314 , in which context program 122 determines a second user device that does have a suitable interface. For example, context program 122 could determine that user device 132 has a suitable interface for surfacing a particular kind of interface. In step 316 , for surfacing a particular kind of interface transmits a context information request to the determined user device. For example, context program 122 can send context information request 264 to user device 132 . Upon receiving context information request 264 , user device 132 surfaces an interface suitable for gathering context information from person 102 . For example, user device 132 may surface a visual interface, an audio interface, or any other kind of user interface.
In step 318 , context program 122 receives a context information reply from the determined user device. For example, in one embodiment context program 122 receives context information reply 266 from user device 132 , after user device 132 interacts with person 102 using a surfaced interface to gather context information. In step 320 , context program 122 determines whether the context information reply is inadequate. For example, context program 122 can determine whether context information reply 266 is inadequate. If the context information reply is inadequate, then flowchart 300 proceeds back to step 316 , in which context program 122 attempts to gain missing or additional context information from person 102 . If the context information reply is adequate, then flowchart 300 proceeds to step 322 . In step 322 , context program 122 transmits a context information message to the recipient user device. For example, context program 122 can transmit context information message 268 to user device 140 . Person 104 can view and consider the gathered context information within context information message 268 utilizing user device 140 , to decide whether and how to respond to or acknowledge communication 260 . If person 104 desires to respond to or acknowledge communication 260 , then in step 324 the communication is released to the recipient user device. For example, in one embodiment, in which communication 260 was intercepted directly at server 120 , context program 122 can release communication 260 to user device 140 . In another embodiment in which communication 260 was intercepted at user device 140 and redirected to server 120 , communication 260 is released upon user device 140 without the direct involvement of context program 122 .
FIG. 4 shows a block diagram of the components of a data processing system 800 , 900 , such as server 120 , user device 130 , user device 132 , or user device 140 , in accordance with an illustrative embodiment of the present invention. It should be appreciated that FIG. 4 provides only an illustration of one implementation and does not imply any limitations with regard to the environments in which different embodiments may be implemented. Many modifications to the depicted environments may be made based on design and implementation requirements.
Data processing system 800 , 900 is representative of any electronic device capable of executing machine-readable program instructions. Data processing system 800 , 900 may be representative of a smart phone, a computer system, a PDA, or other electronic devices. Examples of computing systems, environments, and/or configurations that may represented by data processing system 800 , 900 include, but are not limited to, personal computer systems, server computer systems, thin clients, thick clients, hand-held or laptop devices, multiprocessor systems, microprocessor-based systems, network PCs, minicomputer systems, and distributed cloud computing environments that include any of the above systems or devices.
Server 120 , user device 130 , user device 132 , or user device 140 include respective sets of internal components 800 a, b, c and external components 900 a, b, c illustrated in FIG. 4 . Each of the sets of internal components 800 a, b, c includes one or more processors 820 , one or more computer-readable RAMs 822 and one or more computer-readable ROMs 824 on one or more buses 826 , and one or more operating systems 828 and one or more computer-readable tangible storage devices 830 . The one or more operating systems 828 and context program 122 are stored on one or more of the respective computer-readable tangible storage devices 830 for execution by one or more of the respective processors 820 via one or more of the respective RAMs 822 (which typically include cache memory). In the embodiment illustrated in FIG. 4 , each of the computer-readable tangible storage devices 830 is a magnetic disk storage device of an internal hard drive. Alternatively, each of the computer-readable tangible storage devices 830 is a semiconductor storage device such as ROM 824 , EPROM, flash memory or any other computer-readable tangible storage device that can store a computer program and digital information.
Each set of internal components 800 a, b, c also includes a R/W drive or interface 832 to read from and write to one or more portable computer-readable tangible storage devices 936 such as a CD-ROM, DVD, memory stick, magnetic tape, magnetic disk, optical disk or semiconductor storage device. Context program 122 can be stored on one or more of the respective portable computer-readable tangible storage devices 936 , read via the respective R/W drive or interface 832 and loaded into the respective storage device 830 .
Each set of internal components 800 a, b, c also includes network adapters or interfaces 836 such as a TCP/IP adapter cards, wireless wi-fi interface cards, or 3G or 4G wireless interface cards or other wired or wireless communication links. Context program 122 can be downloaded to server 120 from an external computer via a network (for example, the Internet, a local area network or other, wide area network) and respective network adapters or interfaces 836 . From the network adapters or interfaces 836 , context program 122 is loaded into the respective storage device 830 . The network may comprise copper wires, optical fibers, wireless transmission, routers, firewalls, switches, gateway computers and/or edge servers.
Each of the sets of external components 900 a, b, c can include a computer display monitor 920 , a keyboard 930 , and a computer mouse 934 . External components 900 a, b, c can also include touch screens, virtual keyboards, touch pads, pointing devices, and other human interface devices. Each of the sets of internal components 800 a, b, c also includes device drivers 840 to interface to computer display monitor 920 , keyboard 930 and computer mouse 934 . The device drivers 840 , R/W drive or interface 832 and network adapters or interfaces 836 comprise hardware and software (stored in storage device 830 and/or ROM 824 ).
Aspects of the present invention have been described with respect to block diagrams and/or flowchart illustrations of methods, apparatus (system), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and/or block diagrams, and combinations of blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer instructions. These computer instructions may be provided to a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine, such that instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions/acts specified in the flowchart and/or block diagram block or blocks.
The aforementioned programs can be written in any combination of one or more programming languages, including low-level, high-level, object-oriented or non object-oriented languages, such as Java, Smalltalk, C, and C++. The program code may execute entirely on the user's computer, partly on the user's computer, as a stand-alone software package, partly on the user's computer and partly on a remote computer, or entirely on a remote computer or server. In the latter scenario, the remote computer may be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or the connection may be made to an external computer (for example, through the Internet using an Internet service provider). Alternatively, the functions of the aforementioned programs can be implemented in whole or in part by computer circuits and other hardware (not shown).
Based on the foregoing, computer system, method and program product have been disclosed in accordance with the present invention. However, numerous modifications and substitutions can be made without deviating from the scope of the present invention. Therefore, the present invention has been disclosed by way of example and not limitation. The foregoing description of various embodiments of the present invention has been presented for purposes of illustration and description. It is not intended to be exhaustive nor to limit the invention to the precise form disclosed. Many modifications and variations are possible. Such modifications and variations that may be apparent to a person skilled in the art of the invention are intended to be included within the scope of the invention as defined by the accompanying claims. | A computer receives a first information related to a communication sent to a user device of a second person. The computer determines a user device of a first person using the first information. The computer sends a context information request to the user device of the first person. The computer receives a context information reply responsive to the context information request. The computer sends context information of the context information reply to the user device of the second person. The computer releases the communication to the user device of the second person. | 7 |
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